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/***********************************************************************
Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2009, Percona Inc.
Copyright (c) 2013, 2019, MariaDB Corporation.
Portions of this file contain modifications contributed and copyrighted
by Percona Inc.. Those modifications are
gratefully acknowledged and are described briefly in the InnoDB
documentation. The contributions by Percona Inc. are incorporated with
their permission, and subject to the conditions contained in the file
COPYING.Percona.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
***********************************************************************/
/**************************************************//**
@file os/os0file.cc
The interface to the operating system file i/o primitives
Created 10/21/1995 Heikki Tuuri
*******************************************************/
#ifndef UNIV_INNOCHECKSUM
#include "os0file.h"
#include "sql_const.h"
#ifdef UNIV_LINUX
#include <sys/types.h>
#include <sys/stat.h>
#endif
#include "srv0srv.h"
#include "srv0start.h"
#include "fil0fil.h"
#include "srv0srv.h"
#ifdef HAVE_LINUX_UNISTD_H
#include "unistd.h"
#endif
#include "os0event.h"
#include "os0thread.h"
#include <vector>
#ifdef LINUX_NATIVE_AIO
#include <libaio.h>
#endif /* LINUX_NATIVE_AIO */
#ifdef HAVE_FALLOC_PUNCH_HOLE_AND_KEEP_SIZE
# include <fcntl.h>
# include <linux/falloc.h>
#endif /* HAVE_FALLOC_PUNCH_HOLE_AND_KEEP_SIZE */
#if defined(UNIV_LINUX) && defined(HAVE_SYS_IOCTL_H)
# include <sys/ioctl.h>
# ifndef DFS_IOCTL_ATOMIC_WRITE_SET
# define DFS_IOCTL_ATOMIC_WRITE_SET _IOW(0x95, 2, uint)
# endif
#endif
#if defined(UNIV_LINUX) && defined(HAVE_SYS_STATVFS_H)
#include <sys/statvfs.h>
#endif
#if defined(UNIV_LINUX) && defined(HAVE_LINUX_FALLOC_H)
#include <linux/falloc.h>
#endif
#ifdef _WIN32
#include <winioctl.h>
#endif
/** Insert buffer segment id */
static const ulint IO_IBUF_SEGMENT = 0;
/** Log segment id */
static const ulint IO_LOG_SEGMENT = 1;
/** Number of retries for partial I/O's */
static const ulint NUM_RETRIES_ON_PARTIAL_IO = 10;
/* This specifies the file permissions InnoDB uses when it creates files in
Unix; the value of os_innodb_umask is initialized in ha_innodb.cc to
my_umask */
#ifndef _WIN32
/** Umask for creating files */
static ulint os_innodb_umask = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
#else
/** Umask for creating files */
static ulint os_innodb_umask = 0;
static HANDLE data_completion_port;
static HANDLE log_completion_port;
static DWORD fls_sync_io = FLS_OUT_OF_INDEXES;
#define IOCP_SHUTDOWN_KEY (ULONG_PTR)-1
#endif /* _WIN32 */
/** In simulated aio, merge at most this many consecutive i/os */
static const ulint OS_AIO_MERGE_N_CONSECUTIVE = 64;
/** Flag indicating if the page_cleaner is in active state. */
extern bool buf_page_cleaner_is_active;
#ifdef WITH_INNODB_DISALLOW_WRITES
#define WAIT_ALLOW_WRITES() os_event_wait(srv_allow_writes_event)
#else
#define WAIT_ALLOW_WRITES() do { } while (0)
#endif /* WITH_INNODB_DISALLOW_WRITES */
/**********************************************************************
InnoDB AIO Implementation:
=========================
We support native AIO for Windows and Linux. For rest of the platforms
we simulate AIO by special IO-threads servicing the IO-requests.
Simulated AIO:
==============
On platforms where we 'simulate' AIO, the following is a rough explanation
of the high level design.
There are four io-threads (for ibuf, log, read, write).
All synchronous IO requests are serviced by the calling thread using
os_file_write/os_file_read. The Asynchronous requests are queued up
in an array (there are four such arrays) by the calling thread.
Later these requests are picked up by the IO-thread and are serviced
synchronously.
Windows native AIO:
==================
If srv_use_native_aio is not set then Windows follow the same
code as simulated AIO. If the flag is set then native AIO interface
is used. On windows, one of the limitation is that if a file is opened
for AIO no synchronous IO can be done on it. Therefore we have an
extra fifth array to queue up synchronous IO requests.
There are innodb_file_io_threads helper threads. These threads work
on the four arrays mentioned above in Simulated AIO. No thread is
required for the sync array.
If a synchronous IO request is made, it is first queued in the sync
array. Then the calling thread itself waits on the request, thus
making the call synchronous.
If an AIO request is made the calling thread not only queues it in the
array but also submits the requests. The helper thread then collects
the completed IO request and calls completion routine on it.
Linux native AIO:
=================
If we have libaio installed on the system and innodb_use_native_aio
is set to true we follow the code path of native AIO, otherwise we
do simulated AIO.
There are innodb_file_io_threads helper threads. These threads work
on the four arrays mentioned above in Simulated AIO.
If a synchronous IO request is made, it is handled by calling
os_file_write/os_file_read.
If an AIO request is made the calling thread not only queues it in the
array but also submits the requests. The helper thread then collects
the completed IO request and calls completion routine on it.
**********************************************************************/
#ifdef UNIV_PFS_IO
/* Keys to register InnoDB I/O with performance schema */
mysql_pfs_key_t innodb_data_file_key;
mysql_pfs_key_t innodb_log_file_key;
mysql_pfs_key_t innodb_temp_file_key;
#endif /* UNIV_PFS_IO */
class AIO;
/** The asynchronous I/O context */
struct Slot {
#ifdef WIN_ASYNC_IO
/** Windows control block for the aio request
must be at the very start of Slot, so we can
cast Slot* to OVERLAPPED*
*/
OVERLAPPED control;
#endif
/** index of the slot in the aio array */
uint16_t pos;
/** true if this slot is reserved */
bool is_reserved;
/** time when reserved */
time_t reservation_time;
/** buffer used in i/o */
byte* buf;
/** Buffer pointer used for actual IO. We advance this
when partial IO is required and not buf */
byte* ptr;
/** OS_FILE_READ or OS_FILE_WRITE */
IORequest type;
/** file offset in bytes */
os_offset_t offset;
/** file where to read or write */
pfs_os_file_t file;
/** file name or path */
const char* name;
/** used only in simulated aio: true if the physical i/o
already made and only the slot message needs to be passed
to the caller of os_aio_simulated_handle */
bool io_already_done;
/*!< file block size */
ulint file_block_size;
/** The file node for which the IO is requested. */
fil_node_t* m1;
/** the requester of an aio operation and which can be used
to identify which pending aio operation was completed */
void* m2;
/** AIO completion status */
dberr_t err;
#ifdef WIN_ASYNC_IO
/** bytes written/read */
DWORD n_bytes;
/** length of the block to read or write */
DWORD len;
/** aio array containing this slot */
AIO *array;
#elif defined(LINUX_NATIVE_AIO)
/** Linux control block for aio */
struct iocb control;
/** AIO return code */
int ret;
/** bytes written/read. */
ssize_t n_bytes;
/** length of the block to read or write */
ulint len;
#else
/** length of the block to read or write */
ulint len;
/** bytes written/read. */
ulint n_bytes;
#endif /* WIN_ASYNC_IO */
/** Length of the block before it was compressed */
uint32 original_len;
};
/** The asynchronous i/o array structure */
class AIO {
public:
/** Constructor
@param[in] id Latch ID
@param[in] n_slots Number of slots to configure
@param[in] segments Number of segments to configure */
AIO(latch_id_t id, ulint n_slots, ulint segments);
/** Destructor */
~AIO();
/** Initialize the instance
@return DB_SUCCESS or error code */
dberr_t init();
/** Requests for a slot in the aio array. If no slot is available, waits
until not_full-event becomes signaled.
@param[in] type IO context
@param[in,out] m1 message to be passed along with the AIO
operation
@param[in,out] m2 message to be passed along with the AIO
operation
@param[in] file file handle
@param[in] name name of the file or path as a null-terminated
string
@param[in,out] buf buffer where to read or from which to write
@param[in] offset file offset, where to read from or start writing
@param[in] len length of the block to read or write
@return pointer to slot */
Slot* reserve_slot(
const IORequest& type,
fil_node_t* m1,
void* m2,
pfs_os_file_t file,
const char* name,
void* buf,
os_offset_t offset,
ulint len)
MY_ATTRIBUTE((warn_unused_result));
/** @return number of reserved slots */
ulint pending_io_count() const;
/** Returns a pointer to the nth slot in the aio array.
@param[in] index Index of the slot in the array
@return pointer to slot */
const Slot* at(ulint i) const
MY_ATTRIBUTE((warn_unused_result))
{
ut_a(i < m_slots.size());
return(&m_slots[i]);
}
/** Non const version */
Slot* at(ulint i)
MY_ATTRIBUTE((warn_unused_result))
{
ut_a(i < m_slots.size());
return(&m_slots[i]);
}
/** Frees a slot in the AIO array, assumes caller owns the mutex.
@param[in,out] slot Slot to release */
void release(Slot* slot);
/** Frees a slot in the AIO array, assumes caller doesn't own the mutex.
@param[in,out] slot Slot to release */
void release_with_mutex(Slot* slot);
/** Prints info about the aio array.
@param[in,out] file Where to print */
void print(FILE* file);
/** @return the number of slots per segment */
ulint slots_per_segment() const
MY_ATTRIBUTE((warn_unused_result))
{
return(m_slots.size() / m_n_segments);
}
/** @return accessor for n_segments */
ulint get_n_segments() const
MY_ATTRIBUTE((warn_unused_result))
{
return(m_n_segments);
}
#ifdef UNIV_DEBUG
/** @return true if the thread owns the mutex */
bool is_mutex_owned() const
MY_ATTRIBUTE((warn_unused_result))
{
return(mutex_own(&m_mutex));
}
#endif /* UNIV_DEBUG */
/** Acquire the mutex */
void acquire() const
{
mutex_enter(&m_mutex);
}
/** Release the mutex */
void release() const
{
mutex_exit(&m_mutex);
}
/** Write out the state to the file/stream
@param[in, out] file File to write to */
void to_file(FILE* file) const;
#ifdef LINUX_NATIVE_AIO
/** Dispatch an AIO request to the kernel.
@param[in,out] slot an already reserved slot
@return true on success. */
bool linux_dispatch(Slot* slot)
MY_ATTRIBUTE((warn_unused_result));
/** Accessor for an AIO event
@param[in] index Index into the array
@return the event at the index */
io_event* io_events(ulint index)
MY_ATTRIBUTE((warn_unused_result))
{
ut_a(index < m_events.size());
return(&m_events[index]);
}
/** Accessor for the AIO context
@param[in] segment Segment for which to get the context
@return the AIO context for the segment */
io_context* io_ctx(ulint segment)
MY_ATTRIBUTE((warn_unused_result))
{
ut_ad(segment < get_n_segments());
return(m_aio_ctx[segment]);
}
/** Creates an io_context for native linux AIO.
@param[in] max_events number of events
@param[out] io_ctx io_ctx to initialize.
@return true on success. */
static bool linux_create_io_ctx(unsigned max_events, io_context_t* io_ctx)
MY_ATTRIBUTE((warn_unused_result));
/** Checks if the system supports native linux aio. On some kernel
versions where native aio is supported it won't work on tmpfs. In such
cases we can't use native aio as it is not possible to mix simulated
and native aio.
@return true if supported, false otherwise. */
static bool is_linux_native_aio_supported()
MY_ATTRIBUTE((warn_unused_result));
#endif /* LINUX_NATIVE_AIO */
#ifdef WIN_ASYNC_IO
HANDLE m_completion_port;
/** Wake up all AIO threads in Windows native aio */
static void wake_at_shutdown() {
AIO *all_arrays[] = {s_reads, s_writes, s_log, s_ibuf };
for (size_t i = 0; i < array_elements(all_arrays); i++) {
AIO *a = all_arrays[i];
if (a) {
PostQueuedCompletionStatus(a->m_completion_port, 0,
IOCP_SHUTDOWN_KEY, 0);
}
}
}
#endif /* WIN_ASYNC_IO */
#ifdef _WIN32
/** This function can be called if one wants to post a batch of reads
and prefers an I/O - handler thread to handle them all at once later.You
must call os_aio_simulated_wake_handler_threads later to ensure the
threads are not left sleeping! */
static void simulated_put_read_threads_to_sleep();
#endif /* _WIN32 */
/** Create an instance using new(std::nothrow)
@param[in] id Latch ID
@param[in] n_slots The number of AIO request slots
@param[in] segments The number of segments
@return a new AIO instance */
static AIO* create(
latch_id_t id,
ulint n_slots,
ulint segments)
MY_ATTRIBUTE((warn_unused_result));
/** Initializes the asynchronous io system. Creates one array each
for ibuf and log I/O. Also creates one array each for read and write
where each array is divided logically into n_readers and n_writers
respectively. The caller must create an i/o handler thread for each
segment in these arrays. This function also creates the sync array.
No I/O handler thread needs to be created for that
@param[in] n_per_seg maximum number of pending aio
operations allowed per segment
@param[in] n_readers number of reader threads
@param[in] n_writers number of writer threads
@param[in] n_slots_sync number of slots in the sync aio array
@return true if AIO sub-system was started successfully */
static bool start(
ulint n_per_seg,
ulint n_readers,
ulint n_writers,
ulint n_slots_sync)
MY_ATTRIBUTE((warn_unused_result));
/** Free the AIO arrays */
static void shutdown();
/** Print all the AIO segments
@param[in,out] file Where to print */
static void print_all(FILE* file);
/** Calculates local segment number and aio array from global
segment number.
@param[out] array AIO wait array
@param[in] segment global segment number
@return local segment number within the aio array */
static ulint get_array_and_local_segment(
AIO** array,
ulint segment)
MY_ATTRIBUTE((warn_unused_result));
/** Select the IO slot array
@param[in,out] type Type of IO, READ or WRITE
@param[in] read_only true if running in read-only mode
@param[in] mode IO mode
@return slot array or NULL if invalid mode specified */
static AIO* select_slot_array(
IORequest& type,
bool read_only,
ulint mode)
MY_ATTRIBUTE((warn_unused_result));
/** Calculates segment number for a slot.
@param[in] array AIO wait array
@param[in] slot slot in this array
@return segment number (which is the number used by, for example,
I/O handler threads) */
static ulint get_segment_no_from_slot(
const AIO* array,
const Slot* slot)
MY_ATTRIBUTE((warn_unused_result));
/** Wakes up a simulated AIO I/O-handler thread if it has something
to do.
@param[in] global_segment the number of the segment in the
AIO arrays */
static void wake_simulated_handler_thread(ulint global_segment);
/** Check if it is a read request
@param[in] aio The AIO instance to check
@return true if the AIO instance is for reading. */
static bool is_read(const AIO* aio)
MY_ATTRIBUTE((warn_unused_result))
{
return(s_reads == aio);
}
/** Wait on an event until no pending writes */
static void wait_until_no_pending_writes()
{
os_event_wait(AIO::s_writes->m_is_empty);
}
/** Print to file
@param[in] file File to write to */
static void print_to_file(FILE* file);
/** Check for pending IO. Gets the count and also validates the
data structures.
@return count of pending IO requests */
static ulint total_pending_io_count();
private:
/** Initialise the slots
@return DB_SUCCESS or error code */
dberr_t init_slots()
MY_ATTRIBUTE((warn_unused_result));
/** Wakes up a simulated AIO I/O-handler thread if it has something
to do for a local segment in the AIO array.
@param[in] global_segment the number of the segment in the
AIO arrays
@param[in] segment the local segment in the AIO array */
void wake_simulated_handler_thread(ulint global_segment, ulint segment);
/** Prints pending IO requests per segment of an aio array.
We probably don't need per segment statistics but they can help us
during development phase to see if the IO requests are being
distributed as expected.
@param[in,out] file file where to print
@param[in] segments pending IO array */
void print_segment_info(
FILE* file,
const ulint* segments);
#ifdef LINUX_NATIVE_AIO
/** Initialise the Linux native AIO data structures
@return DB_SUCCESS or error code */
dberr_t init_linux_native_aio()
MY_ATTRIBUTE((warn_unused_result));
#endif /* LINUX_NATIVE_AIO */
private:
typedef std::vector<Slot> Slots;
/** the mutex protecting the aio array */
mutable SysMutex m_mutex;
/** Pointer to the slots in the array.
Number of elements must be divisible by n_threads. */
Slots m_slots;
/** Number of segments in the aio array of pending aio requests.
A thread can wait separately for any one of the segments. */
ulint m_n_segments;
/** The event which is set to the signaled state when
there is space in the aio outside the ibuf segment;
os_event_set() and os_event_reset() are protected by AIO::m_mutex */
os_event_t m_not_full;
/** The event which is set to the signaled state when
there are no pending i/os in this array;
os_event_set() and os_event_reset() are protected by AIO::m_mutex */
os_event_t m_is_empty;
/** Number of reserved slots in the AIO array outside
the ibuf segment */
ulint m_n_reserved;
#if defined(LINUX_NATIVE_AIO)
typedef std::vector<io_event> IOEvents;
/** completion queue for IO. There is one such queue per
segment. Each thread will work on one ctx exclusively. */
io_context_t* m_aio_ctx;
/** The array to collect completed IOs. There is one such
event for each possible pending IO. The size of the array
is equal to m_slots.size(). */
IOEvents m_events;
#endif /* LINUX_NATIV_AIO */
/** The aio arrays for non-ibuf i/o and ibuf i/o, as well as
sync AIO. These are NULL when the module has not yet been
initialized. */
/** Insert buffer */
static AIO* s_ibuf;
/** Redo log */
static AIO* s_log;
/** Reads */
static AIO* s_reads;
/** Writes */
static AIO* s_writes;
/** Synchronous I/O */
static AIO* s_sync;
};
/** Static declarations */
AIO* AIO::s_reads;
AIO* AIO::s_writes;
AIO* AIO::s_ibuf;
AIO* AIO::s_log;
AIO* AIO::s_sync;
#if defined(LINUX_NATIVE_AIO)
/** timeout for each io_getevents() call = 500ms. */
static const ulint OS_AIO_REAP_TIMEOUT = 500000000UL;
/** time to sleep, in microseconds if io_setup() returns EAGAIN. */
static const ulint OS_AIO_IO_SETUP_RETRY_SLEEP = 500000UL;
/** number of attempts before giving up on io_setup(). */
static const int OS_AIO_IO_SETUP_RETRY_ATTEMPTS = 5;
#endif /* LINUX_NATIVE_AIO */
/** Array of events used in simulated AIO */
static os_event_t* os_aio_segment_wait_events;
/** Number of asynchronous I/O segments. Set by os_aio_init(). */
static ulint os_aio_n_segments = ULINT_UNDEFINED;
/** If the following is true, read i/o handler threads try to
wait until a batch of new read requests have been posted */
static bool os_aio_recommend_sleep_for_read_threads;
ulint os_n_file_reads;
static ulint os_bytes_read_since_printout;
ulint os_n_file_writes;
ulint os_n_fsyncs;
static ulint os_n_file_reads_old;
static ulint os_n_file_writes_old;
static ulint os_n_fsyncs_old;
static time_t os_last_printout;
bool os_has_said_disk_full;
/** Default Zip compression level */
extern uint page_zip_level;
/** Validates the consistency of the aio system.
@return true if ok */
static
bool
os_aio_validate();
/** Handle errors for file operations.
@param[in] name name of a file or NULL
@param[in] operation operation
@param[in] should_abort whether to abort on an unknown error
@param[in] on_error_silent whether to suppress reports of non-fatal errors
@return true if we should retry the operation */
static MY_ATTRIBUTE((warn_unused_result))
bool
os_file_handle_error_cond_exit(
const char* name,
const char* operation,
bool should_abort,
bool on_error_silent);
/** Does error handling when a file operation fails.
@param[in] name name of a file or NULL
@param[in] operation operation name that failed
@return true if we should retry the operation */
static
bool
os_file_handle_error(
const char* name,
const char* operation)
{
/* Exit in case of unknown error */
return(os_file_handle_error_cond_exit(name, operation, true, false));
}
/** Does error handling when a file operation fails.
@param[in] name name of a file or NULL
@param[in] operation operation name that failed
@param[in] on_error_silent if true then don't print any message to the log.
@return true if we should retry the operation */
static
bool
os_file_handle_error_no_exit(
const char* name,
const char* operation,
bool on_error_silent)
{
/* Don't exit in case of unknown error */
return(os_file_handle_error_cond_exit(
name, operation, false, on_error_silent));
}
/** Handle RENAME error.
@param name old name of the file
@param new_name new name of the file */
static void os_file_handle_rename_error(const char* name, const char* new_name)
{
if (os_file_get_last_error(true) != OS_FILE_DISK_FULL) {
ib::error() << "Cannot rename file '" << name << "' to '"
<< new_name << "'";
} else if (!os_has_said_disk_full) {
os_has_said_disk_full = true;
/* Disk full error is reported irrespective of the
on_error_silent setting. */
ib::error() << "Full disk prevents renaming file '"
<< name << "' to '" << new_name << "'";
}
}
/** Does simulated AIO. This function should be called by an i/o-handler
thread.
@param[in] segment The number of the segment in the aio arrays to wait
for; segment 0 is the ibuf i/o thread, segment 1 the
log i/o thread, then follow the non-ibuf read threads,
and as the last are the non-ibuf write threads
@param[out] m1 the messages passed with the AIO request; note that
also in the case where the AIO operation failed, these
output parameters are valid and can be used to restart
the operation, for example
@param[out] m2 Callback argument
@param[in] type IO context
@return DB_SUCCESS or error code */
static
dberr_t
os_aio_simulated_handler(
ulint global_segment,
fil_node_t** m1,
void** m2,
IORequest* type);
#ifdef _WIN32
static HANDLE win_get_syncio_event();
/**
Wrapper around Windows DeviceIoControl() function.
Works synchronously, also in case for handle opened
for async access (i.e with FILE_FLAG_OVERLAPPED).
Accepts the same parameters as DeviceIoControl(),except
last parameter (OVERLAPPED).
*/
static
BOOL
os_win32_device_io_control(
HANDLE handle,
DWORD code,
LPVOID inbuf,
DWORD inbuf_size,
LPVOID outbuf,
DWORD outbuf_size,
LPDWORD bytes_returned
)
{
OVERLAPPED overlapped = { 0 };
overlapped.hEvent = win_get_syncio_event();
BOOL result = DeviceIoControl(handle, code, inbuf, inbuf_size, outbuf,
outbuf_size, NULL, &overlapped);
if (result || (GetLastError() == ERROR_IO_PENDING)) {
/* Wait for async io to complete */
result = GetOverlappedResult(handle, &overlapped, bytes_returned, TRUE);
}
return result;
}
#endif
/***********************************************************************//**
Try to get number of bytes per sector from file system.
@return file block size */
UNIV_INTERN
ulint
os_file_get_block_size(
/*===================*/
os_file_t file, /*!< in: handle to a file */
const char* name) /*!< in: file name */
{
ulint fblock_size = 512;
#if defined(UNIV_LINUX)
struct stat local_stat;
int err;
err = fstat((int)file, &local_stat);
if (err != 0) {
os_file_handle_error_no_exit(name, "fstat()", FALSE);
} else {
fblock_size = local_stat.st_blksize;
}
#endif /* UNIV_LINUX */
#ifdef _WIN32
fblock_size = 0;
BOOL result = false;
size_t len = 0;
// Open volume for this file, find out it "physical bytes per sector"
HANDLE volume_handle = INVALID_HANDLE_VALUE;
char volume[MAX_PATH + 4]="\\\\.\\"; // Special prefix required for volume names.
if (!GetVolumePathName(name , volume + 4, MAX_PATH)) {
os_file_handle_error_no_exit(name,
"GetVolumePathName()", FALSE);
goto end;
}
len = strlen(volume);
if (volume[len - 1] == '\\') {
// Trim trailing backslash from volume name.
volume[len - 1] = 0;
}
volume_handle = CreateFile(volume, FILE_READ_ATTRIBUTES,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
0, OPEN_EXISTING, 0, 0);
if (volume_handle == INVALID_HANDLE_VALUE) {
if (GetLastError() != ERROR_ACCESS_DENIED) {
os_file_handle_error_no_exit(volume,
"CreateFile()", FALSE);
}
goto end;
}
DWORD tmp;
STORAGE_ACCESS_ALIGNMENT_DESCRIPTOR disk_alignment;
STORAGE_PROPERTY_QUERY storage_query;
memset(&storage_query, 0, sizeof(storage_query));
storage_query.PropertyId = StorageAccessAlignmentProperty;
storage_query.QueryType = PropertyStandardQuery;
result = os_win32_device_io_control(volume_handle,
IOCTL_STORAGE_QUERY_PROPERTY,
&storage_query,
sizeof(storage_query),
&disk_alignment,
sizeof(disk_alignment),
&tmp);
if (!result) {
DWORD err = GetLastError();
if (err != ERROR_INVALID_FUNCTION && err != ERROR_NOT_SUPPORTED) {
os_file_handle_error_no_exit(volume,
"DeviceIoControl(IOCTL_STORAGE_QUERY_PROPERTY)", FALSE);
}
goto end;
}
fblock_size = disk_alignment.BytesPerPhysicalSector;
end:
if (volume_handle != INVALID_HANDLE_VALUE) {
CloseHandle(volume_handle);
}
#endif /* _WIN32 */
/* Currently we support file block size up to 4Kb */
if (fblock_size > 4096 || fblock_size < 512) {
if (fblock_size < 512) {
fblock_size = 512;
} else {
fblock_size = 4096;
}
}
return fblock_size;
}
#ifdef WIN_ASYNC_IO
/** This function is only used in Windows asynchronous i/o.
Waits for an aio operation to complete. This function is used to wait the
for completed requests. The aio array of pending requests is divided
into segments. The thread specifies which segment or slot it wants to wait
for. NOTE: this function will also take care of freeing the aio slot,
therefore no other thread is allowed to do the freeing!
@param[in] segment The number of the segment in the aio arrays to
wait for; segment 0 is the ibuf I/O thread,
segment 1 the log I/O thread, then follow the
non-ibuf read threads, and as the last are the
non-ibuf write threads; if this is
ULINT_UNDEFINED, then it means that sync AIO
is used, and this parameter is ignored
@param[in] pos this parameter is used only in sync AIO:
wait for the aio slot at this position
@param[out] m1 the messages passed with the AIO request; note
that also in the case where the AIO operation
failed, these output parameters are valid and
can be used to restart the operation,
for example
@param[out] m2 callback message
@param[out] type OS_FILE_WRITE or ..._READ
@return DB_SUCCESS or error code */
static
dberr_t
os_aio_windows_handler(
ulint segment,
ulint pos,
fil_node_t** m1,
void** m2,
IORequest* type);
#endif /* WIN_ASYNC_IO */
/** Generic AIO Handler methods. Currently handles IO post processing. */
class AIOHandler {
public:
/** Do any post processing after a read/write
@return DB_SUCCESS or error code. */
static dberr_t post_io_processing(Slot* slot);
};
/** Helper class for doing synchronous file IO. Currently, the objective
is to hide the OS specific code, so that the higher level functions aren't
peppered with #ifdef. Makes the code flow difficult to follow. */
class SyncFileIO {
public:
/** Constructor
@param[in] fh File handle
@param[in,out] buf Buffer to read/write
@param[in] n Number of bytes to read/write
@param[in] offset Offset where to read or write */
SyncFileIO(os_file_t fh, void* buf, ulint n, os_offset_t offset)
:
m_fh(fh),
m_buf(buf),
m_n(static_cast<ssize_t>(n)),
m_offset(offset)
{
ut_ad(m_n > 0);
}
/** Destructor */
~SyncFileIO()
{
/* No op */
}
/** Do the read/write
@param[in] request The IO context and type
@return the number of bytes read/written or negative value on error */
ssize_t execute(const IORequest& request);
/** Do the read/write
@param[in,out] slot The IO slot, it has the IO context
@return the number of bytes read/written or negative value on error */
static ssize_t execute(Slot* slot);
/** Move the read/write offset up to where the partial IO succeeded.
@param[in] n_bytes The number of bytes to advance */
void advance(ssize_t n_bytes)
{
m_offset += n_bytes;
ut_ad(m_n >= n_bytes);
m_n -= n_bytes;
m_buf = reinterpret_cast<uchar*>(m_buf) + n_bytes;
}
private:
/** Open file handle */
os_file_t m_fh;
/** Buffer to read/write */
void* m_buf;
/** Number of bytes to read/write */
ssize_t m_n;
/** Offset from where to read/write */
os_offset_t m_offset;
};
/** Do any post processing after a read/write
@return DB_SUCCESS or error code. */
dberr_t
AIOHandler::post_io_processing(Slot* slot)
{
ut_ad(slot->is_reserved);
/* Total bytes read so far */
ulint n_bytes = ulint(slot->ptr - slot->buf) + slot->n_bytes;
return(n_bytes == slot->original_len ? DB_SUCCESS : DB_FAIL);
}
/** Count the number of free slots
@return number of reserved slots */
ulint
AIO::pending_io_count() const
{
acquire();
#ifdef UNIV_DEBUG
ut_a(m_n_segments > 0);
ut_a(!m_slots.empty());
ulint count = 0;
for (ulint i = 0; i < m_slots.size(); ++i) {
const Slot& slot = m_slots[i];
if (slot.is_reserved) {
++count;
ut_a(slot.len > 0);
}
}
ut_a(m_n_reserved == count);
#endif /* UNIV_DEBUG */
ulint reserved = m_n_reserved;
release();
return(reserved);
}
#ifdef UNIV_DEBUG
/** Validates the consistency the aio system some of the time.
@return true if ok or the check was skipped */
static
bool
os_aio_validate_skip()
{
/** Try os_aio_validate() every this many times */
# define OS_AIO_VALIDATE_SKIP 13
static int os_aio_validate_count;
if (my_atomic_add32_explicit(&os_aio_validate_count, -1,
MY_MEMORY_ORDER_RELAXED)
% OS_AIO_VALIDATE_SKIP) {
return true;
}
return(os_aio_validate());
}
#endif /* UNIV_DEBUG */
#undef USE_FILE_LOCK
#ifndef _WIN32
/* On Windows, mandatory locking is used */
# define USE_FILE_LOCK
#endif
#ifdef USE_FILE_LOCK
/** Obtain an exclusive lock on a file.
@param[in] fd file descriptor
@param[in] name file name
@return 0 on success */
static
int
os_file_lock(
int fd,
const char* name)
{
struct flock lk;
lk.l_type = F_WRLCK;
lk.l_whence = SEEK_SET;
lk.l_start = lk.l_len = 0;
if (fcntl(fd, F_SETLK, &lk) == -1) {
ib::error()
<< "Unable to lock " << name
<< " error: " << errno;
if (errno == EAGAIN || errno == EACCES) {
ib::info()
<< "Check that you do not already have"
" another mysqld process using the"
" same InnoDB data or log files.";
}
return(-1);
}
return(0);
}
#endif /* USE_FILE_LOCK */
/** Calculates local segment number and aio array from global segment number.
@param[out] array aio wait array
@param[in] segment global segment number
@return local segment number within the aio array */
ulint
AIO::get_array_and_local_segment(
AIO** array,
ulint segment)
{
ulint local_segment;
ulint n_extra_segs = (srv_read_only_mode) ? 0 : 2;
ut_a(segment < os_aio_n_segments);
if (!srv_read_only_mode && segment < n_extra_segs) {
/* We don't support ibuf/log IO during read only mode. */
if (segment == IO_IBUF_SEGMENT) {
*array = s_ibuf;
} else if (segment == IO_LOG_SEGMENT) {
*array = s_log;
} else {
*array = NULL;
}
local_segment = 0;
} else if (segment < s_reads->m_n_segments + n_extra_segs) {
*array = s_reads;
local_segment = segment - n_extra_segs;
} else {
*array = s_writes;
local_segment = segment
- (s_reads->m_n_segments + n_extra_segs);
}
return(local_segment);
}
/** Frees a slot in the aio array. Assumes caller owns the mutex.
@param[in,out] slot Slot to release */
void
AIO::release(Slot* slot)
{
ut_ad(is_mutex_owned());
ut_ad(slot->is_reserved);
slot->is_reserved = false;
--m_n_reserved;
if (m_n_reserved == m_slots.size() - 1) {
os_event_set(m_not_full);
}
if (m_n_reserved == 0) {
os_event_set(m_is_empty);
}
#if defined(LINUX_NATIVE_AIO)
if (srv_use_native_aio) {
memset(&slot->control, 0x0, sizeof(slot->control));
slot->ret = 0;
slot->n_bytes = 0;
} else {
/* These fields should not be used if we are not
using native AIO. */
ut_ad(slot->n_bytes == 0);
ut_ad(slot->ret == 0);
}
#endif /* WIN_ASYNC_IO */
}
/** Frees a slot in the AIO array. Assumes caller doesn't own the mutex.
@param[in,out] slot Slot to release */
void
AIO::release_with_mutex(Slot* slot)
{
acquire();
release(slot);
release();
}
/** Create a temporary file. This function is like tmpfile(3), but
the temporary file is created in the in the mysql server configuration
parameter (--tmpdir).
@return temporary file handle, or NULL on error */
FILE*
os_file_create_tmpfile()
{
FILE* file = NULL;
WAIT_ALLOW_WRITES();
os_file_t fd = innobase_mysql_tmpfile(NULL);
if (fd != OS_FILE_CLOSED) {
#ifdef _WIN32
int crt_fd = _open_osfhandle((intptr_t)HANDLE(fd), 0);
if (crt_fd != -1) {
file = fdopen(crt_fd, "w+b");
if (!file) {
close(crt_fd);
}
}
#else
file = fdopen(fd, "w+b");
if (!file) {
close(fd);
}
#endif
}
if (file == NULL) {
ib::error()
<< "Unable to create temporary file; errno: "
<< errno;
}
return(file);
}
/** Rewind file to its start, read at most size - 1 bytes from it to str, and
NUL-terminate str. All errors are silently ignored. This function is
mostly meant to be used with temporary files.
@param[in,out] file File to read from
@param[in,out] str Buffer where to read
@param[in] size Size of buffer */
void
os_file_read_string(
FILE* file,
char* str,
ulint size)
{
if (size != 0) {
rewind(file);
size_t flen = fread(str, 1, size - 1, file);
str[flen] = '\0';
}
}
/** This function returns a new path name after replacing the basename
in an old path with a new basename. The old_path is a full path
name including the extension. The tablename is in the normal
form "databasename/tablename". The new base name is found after
the forward slash. Both input strings are null terminated.
This function allocates memory to be returned. It is the callers
responsibility to free the return value after it is no longer needed.
@param[in] old_path Pathname
@param[in] tablename Contains new base name
@return own: new full pathname */
char*
os_file_make_new_pathname(
const char* old_path,
const char* tablename)
{
ulint dir_len;
char* last_slash;
char* base_name;
char* new_path;
ulint new_path_len;
/* Split the tablename into its database and table name components.
They are separated by a '/'. */
last_slash = strrchr((char*) tablename, '/');
base_name = last_slash ? last_slash + 1 : (char*) tablename;
/* Find the offset of the last slash. We will strip off the
old basename.ibd which starts after that slash. */
last_slash = strrchr((char*) old_path, OS_PATH_SEPARATOR);
dir_len = last_slash ? ulint(last_slash - old_path) : strlen(old_path);
/* allocate a new path and move the old directory path to it. */
new_path_len = dir_len + strlen(base_name) + sizeof "/.ibd";
new_path = static_cast<char*>(ut_malloc_nokey(new_path_len));
memcpy(new_path, old_path, dir_len);
snprintf(new_path + dir_len, new_path_len - dir_len,
"%c%s.ibd", OS_PATH_SEPARATOR, base_name);
return(new_path);
}
/** This function reduces a null-terminated full remote path name into
the path that is sent by MySQL for DATA DIRECTORY clause. It replaces
the 'databasename/tablename.ibd' found at the end of the path with just
'tablename'.
Since the result is always smaller than the path sent in, no new memory
is allocated. The caller should allocate memory for the path sent in.
This function manipulates that path in place.
If the path format is not as expected, just return. The result is used
to inform a SHOW CREATE TABLE command.
@param[in,out] data_dir_path Full path/data_dir_path */
void
os_file_make_data_dir_path(
char* data_dir_path)
{
/* Replace the period before the extension with a null byte. */
char* ptr = strrchr((char*) data_dir_path, '.');
if (ptr == NULL) {
return;
}
ptr[0] = '\0';
/* The tablename starts after the last slash. */
ptr = strrchr((char*) data_dir_path, OS_PATH_SEPARATOR);
if (ptr == NULL) {
return;
}
ptr[0] = '\0';
char* tablename = ptr + 1;
/* The databasename starts after the next to last slash. */
ptr = strrchr((char*) data_dir_path, OS_PATH_SEPARATOR);
if (ptr == NULL) {
return;
}
ulint tablename_len = ut_strlen(tablename);
ut_memmove(++ptr, tablename, tablename_len);
ptr[tablename_len] = '\0';
}
/** Check if the path refers to the root of a drive using a pointer
to the last directory separator that the caller has fixed.
@param[in] path path name
@param[in] path last directory separator in the path
@return true if this path is a drive root, false if not */
UNIV_INLINE
bool
os_file_is_root(
const char* path,
const char* last_slash)
{
return(
#ifdef _WIN32
(last_slash == path + 2 && path[1] == ':') ||
#endif /* _WIN32 */
last_slash == path);
}
/** Return the parent directory component of a null-terminated path.
Return a new buffer containing the string up to, but not including,
the final component of the path.
The path returned will not contain a trailing separator.
Do not return a root path, return NULL instead.
The final component trimmed off may be a filename or a directory name.
If the final component is the only component of the path, return NULL.
It is the caller's responsibility to free the returned string after it
is no longer needed.
@param[in] path Path name
@return own: parent directory of the path */
static
char*
os_file_get_parent_dir(
const char* path)
{
bool has_trailing_slash = false;
/* Find the offset of the last slash */
const char* last_slash = strrchr(path, OS_PATH_SEPARATOR);
if (!last_slash) {
/* No slash in the path, return NULL */
return(NULL);
}
/* Ok, there is a slash. Is there anything after it? */
if (static_cast<size_t>(last_slash - path + 1) == strlen(path)) {
has_trailing_slash = true;
}
/* Reduce repetative slashes. */
while (last_slash > path
&& last_slash[-1] == OS_PATH_SEPARATOR) {
last_slash--;
}
/* Check for the root of a drive. */
if (os_file_is_root(path, last_slash)) {
return(NULL);
}
/* If a trailing slash prevented the first strrchr() from trimming
the last component of the path, trim that component now. */
if (has_trailing_slash) {
/* Back up to the previous slash. */
last_slash--;
while (last_slash > path
&& last_slash[0] != OS_PATH_SEPARATOR) {
last_slash--;
}
/* Reduce repetative slashes. */
while (last_slash > path
&& last_slash[-1] == OS_PATH_SEPARATOR) {
last_slash--;
}
}
/* Check for the root of a drive. */
if (os_file_is_root(path, last_slash)) {
return(NULL);
}
/* Non-trivial directory component */
return(mem_strdupl(path, ulint(last_slash - path)));
}
#ifdef UNIV_ENABLE_UNIT_TEST_GET_PARENT_DIR
/* Test the function os_file_get_parent_dir. */
void
test_os_file_get_parent_dir(
const char* child_dir,
const char* expected_dir)
{
char* child = mem_strdup(child_dir);
char* expected = expected_dir == NULL ? NULL
: mem_strdup(expected_dir);
/* os_file_get_parent_dir() assumes that separators are
converted to OS_PATH_SEPARATOR. */
os_normalize_path(child);
os_normalize_path(expected);
char* parent = os_file_get_parent_dir(child);
bool unexpected = (expected == NULL
? (parent != NULL)
: (0 != strcmp(parent, expected)));
if (unexpected) {
ib::fatal() << "os_file_get_parent_dir('" << child
<< "') returned '" << parent
<< "', instead of '" << expected << "'.";
}
ut_free(parent);
ut_free(child);
ut_free(expected);
}
/* Test the function os_file_get_parent_dir. */
void
unit_test_os_file_get_parent_dir()
{
test_os_file_get_parent_dir("/usr/lib/a", "/usr/lib");
test_os_file_get_parent_dir("/usr/", NULL);
test_os_file_get_parent_dir("//usr//", NULL);
test_os_file_get_parent_dir("usr", NULL);
test_os_file_get_parent_dir("usr//", NULL);
test_os_file_get_parent_dir("/", NULL);
test_os_file_get_parent_dir("//", NULL);
test_os_file_get_parent_dir(".", NULL);
test_os_file_get_parent_dir("..", NULL);
# ifdef _WIN32
test_os_file_get_parent_dir("D:", NULL);
test_os_file_get_parent_dir("D:/", NULL);
test_os_file_get_parent_dir("D:\\", NULL);
test_os_file_get_parent_dir("D:/data", NULL);
test_os_file_get_parent_dir("D:/data/", NULL);
test_os_file_get_parent_dir("D:\\data\\", NULL);
test_os_file_get_parent_dir("D:///data/////", NULL);
test_os_file_get_parent_dir("D:\\\\\\data\\\\\\\\", NULL);
test_os_file_get_parent_dir("D:/data//a", "D:/data");
test_os_file_get_parent_dir("D:\\data\\\\a", "D:\\data");
test_os_file_get_parent_dir("D:///data//a///b/", "D:///data//a");
test_os_file_get_parent_dir("D:\\\\\\data\\\\a\\\\\\b\\", "D:\\\\\\data\\\\a");
#endif /* _WIN32 */
}
#endif /* UNIV_ENABLE_UNIT_TEST_GET_PARENT_DIR */
/** Creates all missing subdirectories along the given path.
@param[in] path Path name
@return DB_SUCCESS if OK, otherwise error code. */
dberr_t
os_file_create_subdirs_if_needed(
const char* path)
{
if (srv_read_only_mode) {
ib::error()
<< "read only mode set. Can't create "
<< "subdirectories '" << path << "'";
return(DB_READ_ONLY);
}
char* subdir = os_file_get_parent_dir(path);
if (subdir == NULL) {
/* subdir is root or cwd, nothing to do */
return(DB_SUCCESS);
}
/* Test if subdir exists */
os_file_type_t type;
bool subdir_exists;
bool success = os_file_status(subdir, &subdir_exists, &type);
if (success && !subdir_exists) {
/* Subdir does not exist, create it */
dberr_t err = os_file_create_subdirs_if_needed(subdir);
if (err != DB_SUCCESS) {
ut_free(subdir);
return(err);
}
success = os_file_create_directory(subdir, false);
}
ut_free(subdir);
return(success ? DB_SUCCESS : DB_ERROR);
}
#ifndef _WIN32
/** Do the read/write
@param[in] request The IO context and type
@return the number of bytes read/written or negative value on error */
ssize_t
SyncFileIO::execute(const IORequest& request)
{
ssize_t n_bytes;
if (request.is_read()) {
n_bytes = pread(m_fh, m_buf, m_n, m_offset);
} else {
ut_ad(request.is_write());
n_bytes = pwrite(m_fh, m_buf, m_n, m_offset);
}
return(n_bytes);
}
/** Free storage space associated with a section of the file.
@param[in] fh Open file handle
@param[in] off Starting offset (SEEK_SET)
@param[in] len Size of the hole
@return DB_SUCCESS or error code */
static
dberr_t
os_file_punch_hole_posix(
os_file_t fh,
os_offset_t off,
os_offset_t len)
{
#ifdef HAVE_FALLOC_PUNCH_HOLE_AND_KEEP_SIZE
const int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
int ret = fallocate(fh, mode, off, len);
if (ret == 0) {
return(DB_SUCCESS);
}
if (errno == ENOTSUP) {
return(DB_IO_NO_PUNCH_HOLE);
}
ib::warn()
<< "fallocate("
<<", FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, "
<< off << ", " << len << ") returned errno: "
<< errno;
return(DB_IO_ERROR);
#elif defined(UNIV_SOLARIS)
// Use F_FREESP
#endif /* HAVE_FALLOC_PUNCH_HOLE_AND_KEEP_SIZE */
return(DB_IO_NO_PUNCH_HOLE);
}
#if defined(LINUX_NATIVE_AIO)
/** Linux native AIO handler */
class LinuxAIOHandler {
public:
/**
@param[in] global_segment The global segment*/
LinuxAIOHandler(ulint global_segment)
:
m_global_segment(global_segment)
{
/* Should never be doing Sync IO here. */
ut_a(m_global_segment != ULINT_UNDEFINED);
/* Find the array and the local segment. */
m_segment = AIO::get_array_and_local_segment(
&m_array, m_global_segment);
m_n_slots = m_array->slots_per_segment();
}
/** Destructor */
~LinuxAIOHandler()
{
// No op
}
/**
Process a Linux AIO request
@param[out] m1 the messages passed with the
@param[out] m2 AIO request; note that in case the
AIO operation failed, these output
parameters are valid and can be used to
restart the operation.
@param[out] request IO context
@return DB_SUCCESS or error code */
dberr_t poll(fil_node_t** m1, void** m2, IORequest* request);
private:
/** Resubmit an IO request that was only partially successful
@param[in,out] slot Request to resubmit
@return DB_SUCCESS or DB_FAIL if the IO resubmit request failed */
dberr_t resubmit(Slot* slot);
/** Check if the AIO succeeded
@param[in,out] slot The slot to check
@return DB_SUCCESS, DB_FAIL if the operation should be retried or
DB_IO_ERROR on all other errors */
dberr_t check_state(Slot* slot);
/** @return true if a shutdown was detected */
bool is_shutdown() const
{
return(srv_shutdown_state == SRV_SHUTDOWN_EXIT_THREADS
&& !buf_page_cleaner_is_active);
}
/** If no slot was found then the m_array->m_mutex will be released.
@param[out] n_pending The number of pending IOs
@return NULL or a slot that has completed IO */
Slot* find_completed_slot(ulint* n_pending);
/** This is called from within the IO-thread. If there are no completed
IO requests in the slot array, the thread calls this function to
collect more requests from the Linux kernel.
The IO-thread waits on io_getevents(), which is a blocking call, with
a timeout value. Unless the system is very heavy loaded, keeping the
IO-thread very busy, the io-thread will spend most of its time waiting
in this function.
The IO-thread also exits in this function. It checks server status at
each wakeup and that is why we use timed wait in io_getevents(). */
void collect();
private:
/** Slot array */
AIO* m_array;
/** Number of slots inthe local segment */
ulint m_n_slots;
/** The local segment to check */
ulint m_segment;
/** The global segment */
ulint m_global_segment;
};
/** Resubmit an IO request that was only partially successful
@param[in,out] slot Request to resubmit
@return DB_SUCCESS or DB_FAIL if the IO resubmit request failed */
dberr_t
LinuxAIOHandler::resubmit(Slot* slot)
{
#ifdef UNIV_DEBUG
/* Bytes already read/written out */
ulint n_bytes = slot->ptr - slot->buf;
ut_ad(m_array->is_mutex_owned());
ut_ad(n_bytes < slot->original_len);
ut_ad(static_cast<ulint>(slot->n_bytes) < slot->original_len - n_bytes);
/* Partial read or write scenario */
ut_ad(slot->len >= static_cast<ulint>(slot->n_bytes));
#endif /* UNIV_DEBUG */
slot->len -= slot->n_bytes;
slot->ptr += slot->n_bytes;
slot->offset += slot->n_bytes;
/* Resetting the bytes read/written */
slot->n_bytes = 0;
slot->io_already_done = false;
compile_time_assert(sizeof(off_t) >= sizeof(os_offset_t));
struct iocb* iocb = &slot->control;
if (slot->type.is_read()) {
io_prep_pread(
iocb,
slot->file,
slot->ptr,
slot->len,
slot->offset);
} else {
ut_a(slot->type.is_write());
io_prep_pwrite(
iocb,
slot->file,
slot->ptr,
slot->len,
slot->offset);
}
iocb->data = slot;
/* Resubmit an I/O request */
int ret = io_submit(m_array->io_ctx(m_segment), 1, &iocb);
if (ret < -1) {
errno = -ret;
}
return(ret < 0 ? DB_IO_PARTIAL_FAILED : DB_SUCCESS);
}
/** Check if the AIO succeeded
@param[in,out] slot The slot to check
@return DB_SUCCESS, DB_FAIL if the operation should be retried or
DB_IO_ERROR on all other errors */
dberr_t
LinuxAIOHandler::check_state(Slot* slot)
{
ut_ad(m_array->is_mutex_owned());
/* Note that it may be that there is more then one completed
IO requests. We process them one at a time. We may have a case
here to improve the performance slightly by dealing with all
requests in one sweep. */
srv_set_io_thread_op_info(
m_global_segment, "processing completed aio requests");
ut_ad(slot->io_already_done);
dberr_t err = DB_SUCCESS;
if (slot->ret == 0) {
err = AIOHandler::post_io_processing(slot);
} else {
errno = -slot->ret;
/* os_file_handle_error does tell us if we should retry
this IO. As it stands now, we don't do this retry when
reaping requests from a different context than
the dispatcher. This non-retry logic is the same for
Windows and Linux native AIO.
We should probably look into this to transparently
re-submit the IO. */
os_file_handle_error(slot->name, "Linux aio");
err = DB_IO_ERROR;
}
return(err);
}
/** If no slot was found then the m_array->m_mutex will be released.
@param[out] n_pending The number of pending IOs
@return NULL or a slot that has completed IO */
Slot*
LinuxAIOHandler::find_completed_slot(ulint* n_pending)
{
ulint offset = m_n_slots * m_segment;
*n_pending = 0;
m_array->acquire();
Slot* slot = m_array->at(offset);
for (ulint i = 0; i < m_n_slots; ++i, ++slot) {
if (slot->is_reserved) {
++*n_pending;
if (slot->io_already_done) {
/* Something for us to work on.
Note: We don't release the mutex. */
return(slot);
}
}
}
m_array->release();
return(NULL);
}
/** This function is only used in Linux native asynchronous i/o. This is
called from within the io-thread. If there are no completed IO requests
in the slot array, the thread calls this function to collect more
requests from the kernel.
The io-thread waits on io_getevents(), which is a blocking call, with
a timeout value. Unless the system is very heavy loaded, keeping the
io-thread very busy, the io-thread will spend most of its time waiting
in this function.
The io-thread also exits in this function. It checks server status at
each wakeup and that is why we use timed wait in io_getevents(). */
void
LinuxAIOHandler::collect()
{
ut_ad(m_n_slots > 0);
ut_ad(m_array != NULL);
ut_ad(m_segment < m_array->get_n_segments());
/* Which io_context we are going to use. */
io_context* io_ctx = m_array->io_ctx(m_segment);
/* Starting point of the m_segment we will be working on. */
ulint start_pos = m_segment * m_n_slots;
/* End point. */
ulint end_pos = start_pos + m_n_slots;
for (;;) {
struct io_event* events;
/* Which part of event array we are going to work on. */
events = m_array->io_events(m_segment * m_n_slots);
/* Initialize the events. */
memset(events, 0, sizeof(*events) * m_n_slots);
/* The timeout value is arbitrary. We probably need
to experiment with it a little. */
struct timespec timeout;
timeout.tv_sec = 0;
timeout.tv_nsec = OS_AIO_REAP_TIMEOUT;
int ret;
ret = io_getevents(io_ctx, 1, m_n_slots, events, &timeout);
for (int i = 0; i < ret; ++i) {
struct iocb* iocb;
iocb = reinterpret_cast<struct iocb*>(events[i].obj);
ut_a(iocb != NULL);
Slot* slot = reinterpret_cast<Slot*>(iocb->data);
/* Some sanity checks. */
ut_a(slot != NULL);
ut_a(slot->is_reserved);
/* We are not scribbling previous segment. */
ut_a(slot->pos >= start_pos);
/* We have not overstepped to next segment. */
ut_a(slot->pos < end_pos);
/* Deallocate unused blocks from file system.
This is newer done to page 0 or to log files.*/
if (slot->offset > 0
&& !slot->type.is_log()
&& slot->type.is_write()
&& slot->type.punch_hole()) {
slot->err = slot->type.punch_hole(
slot->file,
slot->offset, slot->len);
} else {
slot->err = DB_SUCCESS;
}
/* Mark this request as completed. The error handling
will be done in the calling function. */
m_array->acquire();
/* events[i].res2 should always be ZERO */
ut_ad(events[i].res2 == 0);
slot->io_already_done = true;
/*Even though events[i].res is an unsigned number
in libaio, it is used to return a negative value
(negated errno value) to indicate error and a positive
value to indicate number of bytes read or written. */
if (events[i].res > slot->len) {
/* failure */
slot->n_bytes = 0;
slot->ret = events[i].res;
} else {
/* success */
slot->n_bytes = events[i].res;
slot->ret = 0;
}
m_array->release();
}
if (srv_shutdown_state == SRV_SHUTDOWN_EXIT_THREADS
|| !buf_page_cleaner_is_active
|| ret > 0) {
break;
}
/* This error handling is for any error in collecting the
IO requests. The errors, if any, for any particular IO
request are simply passed on to the calling routine. */
switch (ret) {
case -EAGAIN:
/* Not enough resources! Try again. */
case -EINTR:
/* Interrupted! The behaviour in case of an interrupt.
If we have some completed IOs available then the
return code will be the number of IOs. We get EINTR
only if there are no completed IOs and we have been
interrupted. */
case 0:
/* No pending request! Go back and check again. */
continue;
}
/* All other errors should cause a trap for now. */
ib::fatal()
<< "Unexpected ret_code[" << ret
<< "] from io_getevents()!";
break;
}
}
/** Process a Linux AIO request
@param[out] m1 the messages passed with the
@param[out] m2 AIO request; note that in case the
AIO operation failed, these output
parameters are valid and can be used to
restart the operation.
@param[out] request IO context
@return DB_SUCCESS or error code */
dberr_t
LinuxAIOHandler::poll(fil_node_t** m1, void** m2, IORequest* request)
{
dberr_t err = DB_SUCCESS;
Slot* slot;
/* Loop until we have found a completed request. */
for (;;) {
ulint n_pending;
slot = find_completed_slot(&n_pending);
if (slot != NULL) {
ut_ad(m_array->is_mutex_owned());
err = check_state(slot);
/* DB_FAIL is not a hard error, we should retry */
if (err != DB_FAIL) {
break;
}
/* Partial IO, resubmit request for
remaining bytes to read/write */
err = resubmit(slot);
if (err != DB_SUCCESS) {
break;
}
m_array->release();
} else if (is_shutdown() && n_pending == 0) {
/* There is no completed request. If there is
no pending request at all, and the system is
being shut down, exit. */
*m1 = NULL;
*m2 = NULL;
return(DB_SUCCESS);
} else {
/* Wait for some request. Note that we return
from wait if we have found a request. */
srv_set_io_thread_op_info(
m_global_segment,
"waiting for completed aio requests");
collect();
}
}
if (err == DB_IO_PARTIAL_FAILED) {
/* Aborting in case of submit failure */
ib::fatal()
<< "Native Linux AIO interface. "
"io_submit() call failed when "
"resubmitting a partial I/O "
"request on the file " << slot->name
<< ".";
}
*m1 = slot->m1;
*m2 = slot->m2;
*request = slot->type;
m_array->release(slot);
m_array->release();
return(err);
}
/** This function is only used in Linux native asynchronous i/o.
Waits for an aio operation to complete. This function is used to wait for
the completed requests. The aio array of pending requests is divided
into segments. The thread specifies which segment or slot it wants to wait
for. NOTE: this function will also take care of freeing the aio slot,
therefore no other thread is allowed to do the freeing!
@param[in] global_seg segment number in the aio array
to wait for; segment 0 is the ibuf
i/o thread, segment 1 is log i/o thread,
then follow the non-ibuf read threads,
and the last are the non-ibuf write
threads.
@param[out] m1 the messages passed with the
@param[out] m2 AIO request; note that in case the
AIO operation failed, these output
parameters are valid and can be used to
restart the operation.
@param[out]xi request IO context
@return DB_SUCCESS if the IO was successful */
static
dberr_t
os_aio_linux_handler(
ulint global_segment,
fil_node_t** m1,
void** m2,
IORequest* request)
{
return LinuxAIOHandler(global_segment).poll(m1, m2, request);
}
/** Dispatch an AIO request to the kernel.
@param[in,out] slot an already reserved slot
@return true on success. */
bool
AIO::linux_dispatch(Slot* slot)
{
ut_a(slot->is_reserved);
ut_ad(slot->type.validate());
/* Find out what we are going to work with.
The iocb struct is directly in the slot.
The io_context is one per segment. */
ulint io_ctx_index;
struct iocb* iocb = &slot->control;
io_ctx_index = (slot->pos * m_n_segments) / m_slots.size();
int ret = io_submit(m_aio_ctx[io_ctx_index], 1, &iocb);
/* io_submit() returns number of successfully queued requests
or -errno. */
if (ret != 1) {
errno = -ret;
}
return(ret == 1);
}
/** Creates an io_context for native linux AIO.
@param[in] max_events number of events
@param[out] io_ctx io_ctx to initialize.
@return true on success. */
bool
AIO::linux_create_io_ctx(
unsigned max_events,
io_context_t* io_ctx)
{
ssize_t n_retries = 0;
for (;;) {
memset(io_ctx, 0x0, sizeof(*io_ctx));
/* Initialize the io_ctx. Tell it how many pending
IO requests this context will handle. */
int ret = io_setup(max_events, io_ctx);
if (ret == 0) {
/* Success. Return now. */
return(true);
}
/* If we hit EAGAIN we'll make a few attempts before failing. */
switch (ret) {
case -EAGAIN:
if (n_retries == 0) {
/* First time around. */
ib::warn()
<< "io_setup() failed with EAGAIN."
" Will make "
<< OS_AIO_IO_SETUP_RETRY_ATTEMPTS
<< " attempts before giving up.";
}
if (n_retries < OS_AIO_IO_SETUP_RETRY_ATTEMPTS) {
++n_retries;
ib::warn()
<< "io_setup() attempt "
<< n_retries << ".";
os_thread_sleep(OS_AIO_IO_SETUP_RETRY_SLEEP);
continue;
}
/* Have tried enough. Better call it a day. */
ib::error()
<< "io_setup() failed with EAGAIN after "
<< OS_AIO_IO_SETUP_RETRY_ATTEMPTS
<< " attempts.";
break;
case -ENOSYS:
ib::error()
<< "Linux Native AIO interface"
" is not supported on this platform. Please"
" check your OS documentation and install"
" appropriate binary of InnoDB.";
break;
default:
ib::error()
<< "Linux Native AIO setup"
<< " returned following error["
<< ret << "]";
break;
}
ib::info()
<< "You can disable Linux Native AIO by"
" setting innodb_use_native_aio = 0 in my.cnf";
break;
}
return(false);
}
/** Checks if the system supports native linux aio. On some kernel
versions where native aio is supported it won't work on tmpfs. In such
cases we can't use native aio as it is not possible to mix simulated
and native aio.
@return: true if supported, false otherwise. */
bool
AIO::is_linux_native_aio_supported()
{
int fd;
io_context_t io_ctx;
char name[1000];
if (!linux_create_io_ctx(1, &io_ctx)) {
/* The platform does not support native aio. */
return(false);
} else if (!srv_read_only_mode) {
/* Now check if tmpdir supports native aio ops. */
fd = innobase_mysql_tmpfile(NULL);
if (fd < 0) {
ib::warn()
<< "Unable to create temp file to check"
" native AIO support.";
return(false);
}
} else {
os_normalize_path(srv_log_group_home_dir);
ulint dirnamelen = strlen(srv_log_group_home_dir);
ut_a(dirnamelen < (sizeof name) - 10 - sizeof "ib_logfile");
memcpy(name, srv_log_group_home_dir, dirnamelen);
/* Add a path separator if needed. */
if (dirnamelen && name[dirnamelen - 1] != OS_PATH_SEPARATOR) {
name[dirnamelen++] = OS_PATH_SEPARATOR;
}
strcpy(name + dirnamelen, "ib_logfile0");
fd = open(name, O_RDONLY | O_CLOEXEC);
if (fd == -1) {
ib::warn()
<< "Unable to open"
<< " \"" << name << "\" to check native"
<< " AIO read support.";
return(false);
}
}
struct io_event io_event;
memset(&io_event, 0x0, sizeof(io_event));
byte* buf = static_cast<byte*>(ut_malloc_nokey(srv_page_size * 2));
byte* ptr = static_cast<byte*>(ut_align(buf, srv_page_size));
struct iocb iocb;
/* Suppress valgrind warning. */
memset(buf, 0x00, srv_page_size * 2);
memset(&iocb, 0x0, sizeof(iocb));
struct iocb* p_iocb = &iocb;
if (!srv_read_only_mode) {
io_prep_pwrite(p_iocb, fd, ptr, srv_page_size, 0);
} else {
ut_a(srv_page_size >= 512);
io_prep_pread(p_iocb, fd, ptr, 512, 0);
}
int err = io_submit(io_ctx, 1, &p_iocb);
if (err >= 1) {
/* Now collect the submitted IO request. */
err = io_getevents(io_ctx, 1, 1, &io_event, NULL);
}
ut_free(buf);
close(fd);
switch (err) {
case 1:
return(true);
case -EINVAL:
case -ENOSYS:
ib::error()
<< "Linux Native AIO not supported. You can either"
" move "
<< (srv_read_only_mode ? name : "tmpdir")
<< " to a file system that supports native"
" AIO or you can set innodb_use_native_aio to"
" FALSE to avoid this message.";
/* fall through. */
default:
ib::error()
<< "Linux Native AIO check on "
<< (srv_read_only_mode ? name : "tmpdir")
<< "returned error[" << -err << "]";
}
return(false);
}
#endif /* LINUX_NATIVE_AIO */
/** Retrieves the last error number if an error occurs in a file io function.
The number should be retrieved before any other OS calls (because they may
overwrite the error number). If the number is not known to this program,
the OS error number + 100 is returned.
@param[in] report_all_errors true if we want an error message
printed of all errors
@param[in] on_error_silent true then don't print any diagnostic
to the log
@return error number, or OS error number + 100 */
static
ulint
os_file_get_last_error_low(
bool report_all_errors,
bool on_error_silent)
{
int err = errno;
if (err == 0) {
return(0);
}
if (report_all_errors
|| (err != ENOSPC && err != EEXIST && !on_error_silent)) {
ib::error()
<< "Operating system error number "
<< err
<< " in a file operation.";
if (err == ENOENT) {
ib::error()
<< "The error means the system"
" cannot find the path specified.";
if (srv_is_being_started) {
ib::error()
<< "If you are installing InnoDB,"
" remember that you must create"
" directories yourself, InnoDB"
" does not create them.";
}
} else if (err == EACCES) {
ib::error()
<< "The error means mysqld does not have"
" the access rights to the directory.";
} else {
if (strerror(err) != NULL) {
ib::error()
<< "Error number " << err << " means '"
<< strerror(err) << "'";
}
ib::info() << OPERATING_SYSTEM_ERROR_MSG;
}
}
switch (err) {
case ENOSPC:
return(OS_FILE_DISK_FULL);
case ENOENT:
return(OS_FILE_NOT_FOUND);
case EEXIST:
return(OS_FILE_ALREADY_EXISTS);
case EXDEV:
case ENOTDIR:
case EISDIR:
return(OS_FILE_PATH_ERROR);
case EAGAIN:
if (srv_use_native_aio) {
return(OS_FILE_AIO_RESOURCES_RESERVED);
}
break;
case EINTR:
if (srv_use_native_aio) {
return(OS_FILE_AIO_INTERRUPTED);
}
break;
case EACCES:
return(OS_FILE_ACCESS_VIOLATION);
}
return(OS_FILE_ERROR_MAX + err);
}
/** Wrapper to fsync(2) that retries the call on some errors.
Returns the value 0 if successful; otherwise the value -1 is returned and
the global variable errno is set to indicate the error.
@param[in] file open file handle
@return 0 if success, -1 otherwise */
static
int
os_file_fsync_posix(
os_file_t file)
{
ulint failures = 0;
for (;;) {
++os_n_fsyncs;
int ret = fsync(file);
if (ret == 0) {
return(ret);
}
switch(errno) {
case ENOLCK:
++failures;
ut_a(failures < 1000);
if (!(failures % 100)) {
ib::warn()
<< "fsync(): "
<< "No locks available; retrying";
}
/* 0.2 sec */
os_thread_sleep(200000);
break;
case EINTR:
++failures;
ut_a(failures < 2000);
break;
default:
ib::fatal() << "fsync() returned " << errno;
}
}
}
/** Check the existence and type of the given file.
@param[in] path path name of file
@param[out] exists true if the file exists
@param[out] type Type of the file, if it exists
@return true if call succeeded */
static
bool
os_file_status_posix(
const char* path,
bool* exists,
os_file_type_t* type)
{
struct stat statinfo;
int ret = stat(path, &statinfo);
*exists = !ret;
if (!ret) {
/* file exists, everything OK */
} else if (errno == ENOENT || errno == ENOTDIR || errno == ENAMETOOLONG) {
/* file does not exist */
return(true);
} else {
/* file exists, but stat call failed */
os_file_handle_error_no_exit(path, "stat", false);
return(false);
}
if (S_ISDIR(statinfo.st_mode)) {
*type = OS_FILE_TYPE_DIR;
} else if (S_ISLNK(statinfo.st_mode)) {
*type = OS_FILE_TYPE_LINK;
} else if (S_ISREG(statinfo.st_mode)) {
*type = OS_FILE_TYPE_FILE;
} else {
*type = OS_FILE_TYPE_UNKNOWN;
}
return(true);
}
/** NOTE! Use the corresponding macro os_file_flush(), not directly this
function!
Flushes the write buffers of a given file to the disk.
@param[in] file handle to a file
@return true if success */
bool
os_file_flush_func(
os_file_t file)
{
int ret;
WAIT_ALLOW_WRITES();
ret = os_file_fsync_posix(file);
if (ret == 0) {
return(true);
}
/* Since Linux returns EINVAL if the 'file' is actually a raw device,
we choose to ignore that error if we are using raw disks */
if (srv_start_raw_disk_in_use && errno == EINVAL) {
return(true);
}
ib::error() << "The OS said file flush did not succeed";
os_file_handle_error(NULL, "flush");
/* It is a fatal error if a file flush does not succeed, because then
the database can get corrupt on disk */
ut_error;
return(false);
}
/** NOTE! Use the corresponding macro os_file_create_simple(), not directly
this function!
A simple function to open or create a file.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] access_type OS_FILE_READ_ONLY or OS_FILE_READ_WRITE
@param[in] read_only if true, read only checks are enforced
@param[out] success true if succeed, false if error
@return handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_simple_func(
const char* name,
ulint create_mode,
ulint access_type,
bool read_only,
bool* success)
{
pfs_os_file_t file;
*success = false;
int create_flag;
const char* mode_str = NULL;
if (create_mode != OS_FILE_OPEN && create_mode != OS_FILE_OPEN_RAW) {
WAIT_ALLOW_WRITES();
}
ut_a(!(create_mode & OS_FILE_ON_ERROR_SILENT));
ut_a(!(create_mode & OS_FILE_ON_ERROR_NO_EXIT));
if (create_mode == OS_FILE_OPEN) {
mode_str = "OPEN";
if (access_type == OS_FILE_READ_ONLY) {
create_flag = O_RDONLY;
} else if (read_only) {
create_flag = O_RDONLY;
} else {
create_flag = O_RDWR;
}
} else if (read_only) {
mode_str = "OPEN";
create_flag = O_RDONLY;
} else if (create_mode == OS_FILE_CREATE) {
mode_str = "CREATE";
create_flag = O_RDWR | O_CREAT | O_EXCL;
} else if (create_mode == OS_FILE_CREATE_PATH) {
mode_str = "CREATE PATH";
/* Create subdirs along the path if needed. */
*success = os_file_create_subdirs_if_needed(name);
if (!*success) {
ib::error()
<< "Unable to create subdirectories '"
<< name << "'";
return(OS_FILE_CLOSED);
}
create_flag = O_RDWR | O_CREAT | O_EXCL;
create_mode = OS_FILE_CREATE;
} else {
ib::error()
<< "Unknown file create mode ("
<< create_mode
<< " for file '" << name << "'";
return(OS_FILE_CLOSED);
}
bool retry;
do {
file = open(name, create_flag | O_CLOEXEC, os_innodb_umask);
if (file == -1) {
*success = false;
retry = os_file_handle_error(
name,
create_mode == OS_FILE_OPEN
? "open" : "create");
} else {
*success = true;
retry = false;
}
} while (retry);
/* This function is always called for data files, we should disable
OS caching (O_DIRECT) here as we do in os_file_create_func(), so
we open the same file in the same mode, see man page of open(2). */
if (!srv_read_only_mode
&& *success
&& (srv_file_flush_method == SRV_O_DIRECT
|| srv_file_flush_method == SRV_O_DIRECT_NO_FSYNC)) {
os_file_set_nocache(file, name, mode_str);
}
#ifdef USE_FILE_LOCK
if (!read_only
&& *success
&& (access_type == OS_FILE_READ_WRITE)
&& os_file_lock(file, name)) {
*success = false;
close(file);
file = -1;
}
#endif /* USE_FILE_LOCK */
return(file);
}
/** This function attempts to create a directory named pathname. The new
directory gets default permissions. On Unix the permissions are
(0770 & ~umask). If the directory exists already, nothing is done and
the call succeeds, unless the fail_if_exists arguments is true.
If another error occurs, such as a permission error, this does not crash,
but reports the error and returns false.
@param[in] pathname directory name as null-terminated string
@param[in] fail_if_exists if true, pre-existing directory is treated as
an error.
@return true if call succeeds, false on error */
bool
os_file_create_directory(
const char* pathname,
bool fail_if_exists)
{
int rcode;
WAIT_ALLOW_WRITES();
rcode = mkdir(pathname, 0770);
if (!(rcode == 0 || (errno == EEXIST && !fail_if_exists))) {
/* failure */
os_file_handle_error_no_exit(pathname, "mkdir", false);
return(false);
}
return(true);
}
/**
The os_file_opendir() function opens a directory stream corresponding to the
directory named by the dirname argument. The directory stream is positioned
at the first entry. In both Unix and Windows we automatically skip the '.'
and '..' items at the start of the directory listing.
@param[in] dirname directory name; it must not contain a trailing
'\' or '/'
@param[in] is_fatal true if we should treat an error as a fatal
error; if we try to open symlinks then we do
not wish a fatal error if it happens not to be
a directory
@return directory stream, NULL if error */
os_file_dir_t
os_file_opendir(
const char* dirname,
bool error_is_fatal)
{
os_file_dir_t dir;
dir = opendir(dirname);
if (dir == NULL && error_is_fatal) {
os_file_handle_error(dirname, "opendir");
}
return(dir);
}
/** Closes a directory stream.
@param[in] dir directory stream
@return 0 if success, -1 if failure */
int
os_file_closedir(
os_file_dir_t dir)
{
int ret = closedir(dir);
if (ret != 0) {
os_file_handle_error_no_exit(NULL, "closedir", false);
}
return(ret);
}
/** This function returns information of the next file in the directory. We jump
over the '.' and '..' entries in the directory.
@param[in] dirname directory name or path
@param[in] dir directory stream
@param[out] info buffer where the info is returned
@return 0 if ok, -1 if error, 1 if at the end of the directory */
int
os_file_readdir_next_file(
const char* dirname,
os_file_dir_t dir,
os_file_stat_t* info)
{
struct dirent* ent;
char* full_path;
int ret;
struct stat statinfo;
next_file:
ent = readdir(dir);
if (ent == NULL) {
return(1);
}
ut_a(strlen(ent->d_name) < OS_FILE_MAX_PATH);
if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) {
goto next_file;
}
strcpy(info->name, ent->d_name);
full_path = static_cast<char*>(
ut_malloc_nokey(strlen(dirname) + strlen(ent->d_name) + 10));
sprintf(full_path, "%s/%s", dirname, ent->d_name);
ret = stat(full_path, &statinfo);
if (ret) {
if (errno == ENOENT) {
/* readdir() returned a file that does not exist,
it must have been deleted in the meantime. Do what
would have happened if the file was deleted before
readdir() - ignore and go to the next entry.
If this is the last entry then info->name will still
contain the name of the deleted file when this
function returns, but this is not an issue since the
caller shouldn't be looking at info when end of
directory is returned. */
ut_free(full_path);
goto next_file;
}
os_file_handle_error_no_exit(full_path, "stat", false);
ut_free(full_path);
return(-1);
}
info->size = statinfo.st_size;
if (S_ISDIR(statinfo.st_mode)) {
info->type = OS_FILE_TYPE_DIR;
} else if (S_ISLNK(statinfo.st_mode)) {
info->type = OS_FILE_TYPE_LINK;
} else if (S_ISREG(statinfo.st_mode)) {
info->type = OS_FILE_TYPE_FILE;
} else {
info->type = OS_FILE_TYPE_UNKNOWN;
}
ut_free(full_path);
return(0);
}
/** NOTE! Use the corresponding macro os_file_create(), not directly
this function!
Opens an existing file or creates a new.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] purpose OS_FILE_AIO, if asynchronous, non-buffered I/O
is desired, OS_FILE_NORMAL, if any normal file;
NOTE that it also depends on type, os_aio_..
and srv_.. variables whether we really use async
I/O or unbuffered I/O: look in the function
source code for the exact rules
@param[in] type OS_DATA_FILE or OS_LOG_FILE
@param[in] read_only true, if read only checks should be enforcedm
@param[in] success true if succeeded
@return handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_func(
const char* name,
ulint create_mode,
ulint purpose,
ulint type,
bool read_only,
bool* success)
{
bool on_error_no_exit;
bool on_error_silent;
*success = false;
DBUG_EXECUTE_IF(
"ib_create_table_fail_disk_full",
*success = false;
errno = ENOSPC;
return(OS_FILE_CLOSED);
);
int create_flag;
const char* mode_str = NULL;
on_error_no_exit = create_mode & OS_FILE_ON_ERROR_NO_EXIT
? true : false;
on_error_silent = create_mode & OS_FILE_ON_ERROR_SILENT
? true : false;
create_mode &= ulint(~(OS_FILE_ON_ERROR_NO_EXIT
| OS_FILE_ON_ERROR_SILENT));
if (create_mode == OS_FILE_OPEN
|| create_mode == OS_FILE_OPEN_RAW
|| create_mode == OS_FILE_OPEN_RETRY) {
mode_str = "OPEN";
create_flag = read_only ? O_RDONLY : O_RDWR;
} else if (read_only) {
mode_str = "OPEN";
create_flag = O_RDONLY;
} else if (create_mode == OS_FILE_CREATE) {
mode_str = "CREATE";
create_flag = O_RDWR | O_CREAT | O_EXCL;
} else if (create_mode == OS_FILE_OVERWRITE) {
mode_str = "OVERWRITE";
create_flag = O_RDWR | O_CREAT | O_TRUNC;
} else {
ib::error()
<< "Unknown file create mode (" << create_mode << ")"
<< " for file '" << name << "'";
return(OS_FILE_CLOSED);
}
ut_a(type == OS_LOG_FILE
|| type == OS_DATA_FILE
|| type == OS_DATA_TEMP_FILE);
ut_a(purpose == OS_FILE_AIO || purpose == OS_FILE_NORMAL);
#ifdef O_SYNC
/* We let O_SYNC only affect log files; note that we map O_DSYNC to
O_SYNC because the datasync options seemed to corrupt files in 2001
in both Linux and Solaris */
if (!read_only
&& type == OS_LOG_FILE
&& srv_file_flush_method == SRV_O_DSYNC) {
create_flag |= O_SYNC;
}
#endif /* O_SYNC */
os_file_t file;
bool retry;
do {
file = open(name, create_flag | O_CLOEXEC, os_innodb_umask);
if (file == -1) {
const char* operation;
operation = (create_mode == OS_FILE_CREATE
&& !read_only) ? "create" : "open";
*success = false;
if (on_error_no_exit) {
retry = os_file_handle_error_no_exit(
name, operation, on_error_silent);
} else {
retry = os_file_handle_error(name, operation);
}
} else {
*success = true;
retry = false;
}
} while (retry);
/* We disable OS caching (O_DIRECT) only on data files */
if (!read_only
&& *success
&& (type != OS_LOG_FILE && type != OS_DATA_TEMP_FILE)
&& (srv_file_flush_method == SRV_O_DIRECT
|| srv_file_flush_method == SRV_O_DIRECT_NO_FSYNC)) {
os_file_set_nocache(file, name, mode_str);
}
#ifdef USE_FILE_LOCK
if (!read_only
&& *success
&& create_mode != OS_FILE_OPEN_RAW
&& os_file_lock(file, name)) {
if (create_mode == OS_FILE_OPEN_RETRY) {
ib::info()
<< "Retrying to lock the first data file";
for (int i = 0; i < 100; i++) {
os_thread_sleep(1000000);
if (!os_file_lock(file, name)) {
*success = true;
return(file);
}
}
ib::info()
<< "Unable to open the first data file";
}
*success = false;
close(file);
file = -1;
}
#endif /* USE_FILE_LOCK */
return(file);
}
/** NOTE! Use the corresponding macro
os_file_create_simple_no_error_handling(), not directly this function!
A simple function to open or create a file.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] access_type OS_FILE_READ_ONLY, OS_FILE_READ_WRITE, or
OS_FILE_READ_ALLOW_DELETE; the last option
is used by a backup program reading the file
@param[in] read_only if true read only mode checks are enforced
@param[out] success true if succeeded
@return own: handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_simple_no_error_handling_func(
const char* name,
ulint create_mode,
ulint access_type,
bool read_only,
bool* success)
{
os_file_t file;
int create_flag;
if (create_mode != OS_FILE_OPEN && create_mode != OS_FILE_OPEN_RAW) {
WAIT_ALLOW_WRITES();
}
ut_a(!(create_mode & OS_FILE_ON_ERROR_SILENT));
ut_a(!(create_mode & OS_FILE_ON_ERROR_NO_EXIT));
*success = false;
if (create_mode == OS_FILE_OPEN) {
if (access_type == OS_FILE_READ_ONLY) {
create_flag = O_RDONLY;
} else if (read_only) {
create_flag = O_RDONLY;
} else {
ut_a(access_type == OS_FILE_READ_WRITE
|| access_type == OS_FILE_READ_ALLOW_DELETE);
create_flag = O_RDWR;
}
} else if (read_only) {
create_flag = O_RDONLY;
} else if (create_mode == OS_FILE_CREATE) {
create_flag = O_RDWR | O_CREAT | O_EXCL;
} else {
ib::error()
<< "Unknown file create mode "
<< create_mode << " for file '" << name << "'";
return(OS_FILE_CLOSED);
}
file = open(name, create_flag | O_CLOEXEC, os_innodb_umask);
*success = (file != -1);
#ifdef USE_FILE_LOCK
if (!read_only
&& *success
&& access_type == OS_FILE_READ_WRITE
&& os_file_lock(file, name)) {
*success = false;
close(file);
file = -1;
}
#endif /* USE_FILE_LOCK */
return(file);
}
/** Deletes a file if it exists. The file has to be closed before calling this.
@param[in] name file path as a null-terminated string
@param[out] exist indicate if file pre-exist
@return true if success */
bool
os_file_delete_if_exists_func(
const char* name,
bool* exist)
{
if (exist != NULL) {
*exist = true;
}
int ret;
WAIT_ALLOW_WRITES();
ret = unlink(name);
if (ret != 0 && errno == ENOENT) {
if (exist != NULL) {
*exist = false;
}
} else if (ret != 0 && errno != ENOENT) {
os_file_handle_error_no_exit(name, "delete", false);
return(false);
}
return(true);
}
/** Deletes a file. The file has to be closed before calling this.
@param[in] name file path as a null-terminated string
@return true if success */
bool
os_file_delete_func(
const char* name)
{
int ret;
WAIT_ALLOW_WRITES();
ret = unlink(name);
if (ret != 0) {
os_file_handle_error_no_exit(name, "delete", FALSE);
return(false);
}
return(true);
}
/** NOTE! Use the corresponding macro os_file_rename(), not directly this
function!
Renames a file (can also move it to another directory). It is safest that the
file is closed before calling this function.
@param[in] oldpath old file path as a null-terminated string
@param[in] newpath new file path
@return true if success */
bool
os_file_rename_func(
const char* oldpath,
const char* newpath)
{
#ifdef UNIV_DEBUG
os_file_type_t type;
bool exists;
/* New path must not exist. */
ut_ad(os_file_status(newpath, &exists, &type));
ut_ad(!exists);
/* Old path must exist. */
ut_ad(os_file_status(oldpath, &exists, &type));
ut_ad(exists);
#endif /* UNIV_DEBUG */
int ret;
WAIT_ALLOW_WRITES();
ret = rename(oldpath, newpath);
if (ret != 0) {
os_file_handle_rename_error(oldpath, newpath);
return(false);
}
return(true);
}
/** NOTE! Use the corresponding macro os_file_close(), not directly this
function!
Closes a file handle. In case of error, error number can be retrieved with
os_file_get_last_error.
@param[in] file Handle to close
@return true if success */
bool
os_file_close_func(
os_file_t file)
{
int ret = close(file);
if (ret == -1) {
os_file_handle_error(NULL, "close");
return(false);
}
return(true);
}
/** Gets a file size.
@param[in] file handle to an open file
@return file size, or (os_offset_t) -1 on failure */
os_offset_t
os_file_get_size(os_file_t file)
{
struct stat statbuf;
return fstat(file, &statbuf) ? os_offset_t(-1) : statbuf.st_size;
}
/** Gets a file size.
@param[in] filename Full path to the filename to check
@return file size if OK, else set m_total_size to ~0 and m_alloc_size to
errno */
os_file_size_t
os_file_get_size(
const char* filename)
{
struct stat s;
os_file_size_t file_size;
int ret = stat(filename, &s);
if (ret == 0) {
file_size.m_total_size = s.st_size;
/* st_blocks is in 512 byte sized blocks */
file_size.m_alloc_size = s.st_blocks * 512;
} else {
file_size.m_total_size = ~0U;
file_size.m_alloc_size = (os_offset_t) errno;
}
return(file_size);
}
/** This function returns information about the specified file
@param[in] path pathname of the file
@param[out] stat_info information of a file in a directory
@param[in,out] statinfo information of a file in a directory
@param[in] check_rw_perm for testing whether the file can be opened
in RW mode
@param[in] read_only if true read only mode checks are enforced
@return DB_SUCCESS if all OK */
static
dberr_t
os_file_get_status_posix(
const char* path,
os_file_stat_t* stat_info,
struct stat* statinfo,
bool check_rw_perm,
bool read_only)
{
int ret = stat(path, statinfo);
if (ret && (errno == ENOENT || errno == ENOTDIR
|| errno == ENAMETOOLONG)) {
/* file does not exist */
return(DB_NOT_FOUND);
} else if (ret) {
/* file exists, but stat call failed */
os_file_handle_error_no_exit(path, "stat", false);
return(DB_FAIL);
}
switch (statinfo->st_mode & S_IFMT) {
case S_IFDIR:
stat_info->type = OS_FILE_TYPE_DIR;
break;
case S_IFLNK:
stat_info->type = OS_FILE_TYPE_LINK;
break;
case S_IFBLK:
/* Handle block device as regular file. */
case S_IFCHR:
/* Handle character device as regular file. */
case S_IFREG:
stat_info->type = OS_FILE_TYPE_FILE;
break;
default:
stat_info->type = OS_FILE_TYPE_UNKNOWN;
}
stat_info->size = statinfo->st_size;
stat_info->block_size = statinfo->st_blksize;
stat_info->alloc_size = statinfo->st_blocks * 512;
if (check_rw_perm
&& (stat_info->type == OS_FILE_TYPE_FILE
|| stat_info->type == OS_FILE_TYPE_BLOCK)) {
stat_info->rw_perm = !access(path, read_only
? R_OK : R_OK | W_OK);
}
return(DB_SUCCESS);
}
/** Truncates a file to a specified size in bytes.
Do nothing if the size to preserve is greater or equal to the current
size of the file.
@param[in] pathname file path
@param[in] file file to be truncated
@param[in] size size to preserve in bytes
@return true if success */
static
bool
os_file_truncate_posix(
const char* pathname,
os_file_t file,
os_offset_t size)
{
int res = ftruncate(file, size);
if (res == -1) {
bool retry;
retry = os_file_handle_error_no_exit(
pathname, "truncate", false);
if (retry) {
ib::warn()
<< "Truncate failed for '"
<< pathname << "'";
}
}
return(res == 0);
}
/** Truncates a file at its current position.
@return true if success */
bool
os_file_set_eof(
FILE* file) /*!< in: file to be truncated */
{
WAIT_ALLOW_WRITES();
return(!ftruncate(fileno(file), ftell(file)));
}
#else /* !_WIN32 */
#include <WinIoCtl.h>
/*
Windows : Handling synchronous IO on files opened asynchronously.
If file is opened for asynchronous IO (FILE_FLAG_OVERLAPPED) and also bound to
a completion port, then every IO on this file would normally be enqueued to the
completion port. Sometimes however we would like to do a synchronous IO. This is
possible if we initialitze have overlapped.hEvent with a valid event and set its
lowest order bit to 1 (see MSDN ReadFile and WriteFile description for more info)
We'll create this special event once for each thread and store in thread local
storage.
*/
static void __stdcall win_free_syncio_event(void *data) {
if (data) {
CloseHandle((HANDLE)data);
}
}
/*
Retrieve per-thread event for doing synchronous io on asyncronously opened files
*/
static HANDLE win_get_syncio_event()
{
HANDLE h;
h = (HANDLE)FlsGetValue(fls_sync_io);
if (h) {
return h;
}
h = CreateEventA(NULL, FALSE, FALSE, NULL);
ut_a(h);
/* Set low-order bit to keeps I/O completion from being queued */
h = (HANDLE)((uintptr_t)h | 1);
FlsSetValue(fls_sync_io, h);
return h;
}
/** Do the read/write
@param[in] request The IO context and type
@return the number of bytes read/written or negative value on error */
ssize_t
SyncFileIO::execute(const IORequest& request)
{
OVERLAPPED seek;
memset(&seek, 0x0, sizeof(seek));
seek.hEvent = win_get_syncio_event();
seek.Offset = (DWORD) m_offset & 0xFFFFFFFF;
seek.OffsetHigh = (DWORD) (m_offset >> 32);
BOOL ret;
DWORD n_bytes;
if (request.is_read()) {
ret = ReadFile(m_fh, m_buf,
static_cast<DWORD>(m_n), NULL, &seek);
} else {
ut_ad(request.is_write());
ret = WriteFile(m_fh, m_buf,
static_cast<DWORD>(m_n), NULL, &seek);
}
if (ret || (GetLastError() == ERROR_IO_PENDING)) {
/* Wait for async io to complete */
ret = GetOverlappedResult(m_fh, &seek, &n_bytes, TRUE);
}
return(ret ? static_cast<ssize_t>(n_bytes) : -1);
}
/** Do the read/write
@param[in,out] slot The IO slot, it has the IO context
@return the number of bytes read/written or negative value on error */
ssize_t
SyncFileIO::execute(Slot* slot)
{
BOOL ret;
slot->control.hEvent = win_get_syncio_event();
if (slot->type.is_read()) {
ret = ReadFile(
slot->file, slot->ptr, slot->len,
NULL, &slot->control);
} else {
ut_ad(slot->type.is_write());
ret = WriteFile(
slot->file, slot->ptr, slot->len,
NULL, &slot->control);
}
if (ret || (GetLastError() == ERROR_IO_PENDING)) {
/* Wait for async io to complete */
ret = GetOverlappedResult(slot->file, &slot->control, &slot->n_bytes, TRUE);
}
return(ret ? static_cast<ssize_t>(slot->n_bytes) : -1);
}
/* Startup/shutdown */
struct WinIoInit
{
WinIoInit() {
fls_sync_io = FlsAlloc(win_free_syncio_event);
ut_a(fls_sync_io != FLS_OUT_OF_INDEXES);
}
~WinIoInit() {
FlsFree(fls_sync_io);
}
};
/* Ensures proper initialization and shutdown */
static WinIoInit win_io_init;
/** Free storage space associated with a section of the file.
@param[in] fh Open file handle
@param[in] page_size Tablespace page size
@param[in] block_size File system block size
@param[in] off Starting offset (SEEK_SET)
@param[in] len Size of the hole
@return 0 on success or errno */
static
dberr_t
os_file_punch_hole_win32(
os_file_t fh,
os_offset_t off,
os_offset_t len)
{
FILE_ZERO_DATA_INFORMATION punch;
punch.FileOffset.QuadPart = off;
punch.BeyondFinalZero.QuadPart = off + len;
/* If lpOverlapped is NULL, lpBytesReturned cannot be NULL,
therefore we pass a dummy parameter. */
DWORD temp;
BOOL success = os_win32_device_io_control(
fh, FSCTL_SET_ZERO_DATA, &punch, sizeof(punch),
NULL, 0, &temp);
return(success ? DB_SUCCESS: DB_IO_NO_PUNCH_HOLE);
}
/** Check the existence and type of the given file.
@param[in] path path name of file
@param[out] exists true if the file exists
@param[out] type Type of the file, if it exists
@return true if call succeeded */
static
bool
os_file_status_win32(
const char* path,
bool* exists,
os_file_type_t* type)
{
int ret;
struct _stat64 statinfo;
ret = _stat64(path, &statinfo);
*exists = !ret;
if (!ret) {
/* file exists, everything OK */
} else if (errno == ENOENT || errno == ENOTDIR || errno == ENAMETOOLONG) {
/* file does not exist */
return(true);
} else {
/* file exists, but stat call failed */
os_file_handle_error_no_exit(path, "stat", false);
return(false);
}
if (_S_IFDIR & statinfo.st_mode) {
*type = OS_FILE_TYPE_DIR;
} else if (_S_IFREG & statinfo.st_mode) {
*type = OS_FILE_TYPE_FILE;
} else {
*type = OS_FILE_TYPE_UNKNOWN;
}
return(true);
}
/** NOTE! Use the corresponding macro os_file_flush(), not directly this
function!
Flushes the write buffers of a given file to the disk.
@param[in] file handle to a file
@return true if success */
bool
os_file_flush_func(
os_file_t file)
{
++os_n_fsyncs;
BOOL ret = FlushFileBuffers(file);
if (ret) {
return(true);
}
/* Since Windows returns ERROR_INVALID_FUNCTION if the 'file' is
actually a raw device, we choose to ignore that error if we are using
raw disks */
if (srv_start_raw_disk_in_use && GetLastError()
== ERROR_INVALID_FUNCTION) {
return(true);
}
os_file_handle_error(NULL, "flush");
/* It is a fatal error if a file flush does not succeed, because then
the database can get corrupt on disk */
ut_error;
return(false);
}
/** Retrieves the last error number if an error occurs in a file io function.
The number should be retrieved before any other OS calls (because they may
overwrite the error number). If the number is not known to this program,
the OS error number + 100 is returned.
@param[in] report_all_errors true if we want an error message printed
of all errors
@param[in] on_error_silent true then don't print any diagnostic
to the log
@return error number, or OS error number + 100 */
static
ulint
os_file_get_last_error_low(
bool report_all_errors,
bool on_error_silent)
{
ulint err = (ulint) GetLastError();
if (err == ERROR_SUCCESS) {
return(0);
}
if (report_all_errors
|| (!on_error_silent
&& err != ERROR_DISK_FULL
&& err != ERROR_FILE_EXISTS)) {
ib::error()
<< "Operating system error number " << err
<< " in a file operation.";
if (err == ERROR_PATH_NOT_FOUND) {
ib::error()
<< "The error means the system"
" cannot find the path specified.";
if (srv_is_being_started) {
ib::error()
<< "If you are installing InnoDB,"
" remember that you must create"
" directories yourself, InnoDB"
" does not create them.";
}
} else if (err == ERROR_ACCESS_DENIED) {
ib::error()
<< "The error means mysqld does not have"
" the access rights to"
" the directory. It may also be"
" you have created a subdirectory"
" of the same name as a data file.";
} else if (err == ERROR_SHARING_VIOLATION
|| err == ERROR_LOCK_VIOLATION) {
ib::error()
<< "The error means that another program"
" is using InnoDB's files."
" This might be a backup or antivirus"
" software or another instance"
" of MySQL."
" Please close it to get rid of this error.";
} else if (err == ERROR_WORKING_SET_QUOTA
|| err == ERROR_NO_SYSTEM_RESOURCES) {
ib::error()
<< "The error means that there are no"
" sufficient system resources or quota to"
" complete the operation.";
} else if (err == ERROR_OPERATION_ABORTED) {
ib::error()
<< "The error means that the I/O"
" operation has been aborted"
" because of either a thread exit"
" or an application request."
" Retry attempt is made.";
} else {
ib::info() << OPERATING_SYSTEM_ERROR_MSG;
}
}
if (err == ERROR_FILE_NOT_FOUND) {
return(OS_FILE_NOT_FOUND);
} else if (err == ERROR_DISK_FULL) {
return(OS_FILE_DISK_FULL);
} else if (err == ERROR_FILE_EXISTS) {
return(OS_FILE_ALREADY_EXISTS);
} else if (err == ERROR_SHARING_VIOLATION
|| err == ERROR_LOCK_VIOLATION) {
return(OS_FILE_SHARING_VIOLATION);
} else if (err == ERROR_WORKING_SET_QUOTA
|| err == ERROR_NO_SYSTEM_RESOURCES) {
return(OS_FILE_INSUFFICIENT_RESOURCE);
} else if (err == ERROR_OPERATION_ABORTED) {
return(OS_FILE_OPERATION_ABORTED);
} else if (err == ERROR_ACCESS_DENIED) {
return(OS_FILE_ACCESS_VIOLATION);
}
return(OS_FILE_ERROR_MAX + err);
}
/** NOTE! Use the corresponding macro os_file_create_simple(), not directly
this function!
A simple function to open or create a file.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] access_type OS_FILE_READ_ONLY or OS_FILE_READ_WRITE
@param[in] read_only if true read only mode checks are enforced
@param[out] success true if succeed, false if error
@return handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_simple_func(
const char* name,
ulint create_mode,
ulint access_type,
bool read_only,
bool* success)
{
os_file_t file;
*success = false;
DWORD access;
DWORD create_flag;
DWORD attributes = 0;
ut_a(!(create_mode & OS_FILE_ON_ERROR_SILENT));
ut_a(!(create_mode & OS_FILE_ON_ERROR_NO_EXIT));
ut_ad(srv_operation == SRV_OPERATION_NORMAL);
if (create_mode == OS_FILE_OPEN) {
create_flag = OPEN_EXISTING;
} else if (read_only) {
create_flag = OPEN_EXISTING;
} else if (create_mode == OS_FILE_CREATE) {
create_flag = CREATE_NEW;
} else if (create_mode == OS_FILE_CREATE_PATH) {
/* Create subdirs along the path if needed. */
*success = os_file_create_subdirs_if_needed(name);
if (!*success) {
ib::error()
<< "Unable to create subdirectories '"
<< name << "'";
return(OS_FILE_CLOSED);
}
create_flag = CREATE_NEW;
create_mode = OS_FILE_CREATE;
} else {
ib::error()
<< "Unknown file create mode ("
<< create_mode << ") for file '"
<< name << "'";
return(OS_FILE_CLOSED);
}
if (access_type == OS_FILE_READ_ONLY) {
access = GENERIC_READ;
} else if (read_only) {
ib::info()
<< "Read only mode set. Unable to"
" open file '" << name << "' in RW mode, "
<< "trying RO mode";
access = GENERIC_READ;
} else if (access_type == OS_FILE_READ_WRITE) {
access = GENERIC_READ | GENERIC_WRITE;
} else {
ib::error()
<< "Unknown file access type (" << access_type << ") "
"for file '" << name << "'";
return(OS_FILE_CLOSED);
}
bool retry;
do {
/* Use default security attributes and no template file. */
file = CreateFile(
(LPCTSTR) name, access,
FILE_SHARE_READ | FILE_SHARE_DELETE, NULL,
create_flag, attributes, NULL);
if (file == INVALID_HANDLE_VALUE) {
*success = false;
retry = os_file_handle_error(
name, create_mode == OS_FILE_OPEN ?
"open" : "create");
} else {
retry = false;
*success = true;
}
} while (retry);
return(file);
}
/** This function attempts to create a directory named pathname. The new
directory gets default permissions. On Unix the permissions are
(0770 & ~umask). If the directory exists already, nothing is done and
the call succeeds, unless the fail_if_exists arguments is true.
If another error occurs, such as a permission error, this does not crash,
but reports the error and returns false.
@param[in] pathname directory name as null-terminated string
@param[in] fail_if_exists if true, pre-existing directory is treated
as an error.
@return true if call succeeds, false on error */
bool
os_file_create_directory(
const char* pathname,
bool fail_if_exists)
{
BOOL rcode;
rcode = CreateDirectory((LPCTSTR) pathname, NULL);
if (!(rcode != 0
|| (GetLastError() == ERROR_ALREADY_EXISTS
&& !fail_if_exists))) {
os_file_handle_error_no_exit(
pathname, "CreateDirectory", false);
return(false);
}
return(true);
}
/** The os_file_opendir() function opens a directory stream corresponding to the
directory named by the dirname argument. The directory stream is positioned
at the first entry. In both Unix and Windows we automatically skip the '.'
and '..' items at the start of the directory listing.
@param[in] dirname directory name; it must not contain a trailing
'\' or '/'
@param[in] is_fatal true if we should treat an error as a fatal
error; if we try to open symlinks then we do
not wish a fatal error if it happens not to
be a directory
@return directory stream, NULL if error */
os_file_dir_t
os_file_opendir(
const char* dirname,
bool error_is_fatal)
{
os_file_dir_t dir;
LPWIN32_FIND_DATA lpFindFileData;
char path[OS_FILE_MAX_PATH + 3];
ut_a(strlen(dirname) < OS_FILE_MAX_PATH);
strcpy(path, dirname);
strcpy(path + strlen(path), "\\*");
/* Note that in Windows opening the 'directory stream' also retrieves
the first entry in the directory. Since it is '.', that is no problem,
as we will skip over the '.' and '..' entries anyway. */
lpFindFileData = static_cast<LPWIN32_FIND_DATA>(
ut_malloc_nokey(sizeof(WIN32_FIND_DATA)));
dir = FindFirstFile((LPCTSTR) path, lpFindFileData);
ut_free(lpFindFileData);
if (dir == INVALID_HANDLE_VALUE) {
if (error_is_fatal) {
os_file_handle_error(dirname, "opendir");
}
return(NULL);
}
return(dir);
}
/** Closes a directory stream.
@param[in] dir directory stream
@return 0 if success, -1 if failure */
int
os_file_closedir(
os_file_dir_t dir)
{
BOOL ret;
ret = FindClose(dir);
if (!ret) {
os_file_handle_error_no_exit(NULL, "closedir", false);
return(-1);
}
return(0);
}
/** This function returns information of the next file in the directory. We
jump over the '.' and '..' entries in the directory.
@param[in] dirname directory name or path
@param[in] dir directory stream
@param[out] info buffer where the info is returned
@return 0 if ok, -1 if error, 1 if at the end of the directory */
int
os_file_readdir_next_file(
const char* dirname,
os_file_dir_t dir,
os_file_stat_t* info)
{
BOOL ret;
int status;
WIN32_FIND_DATA find_data;
next_file:
ret = FindNextFile(dir, &find_data);
if (ret > 0) {
const char* name;
name = static_cast<const char*>(find_data.cFileName);
ut_a(strlen(name) < OS_FILE_MAX_PATH);
if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0) {
goto next_file;
}
strcpy(info->name, name);
info->size = find_data.nFileSizeHigh;
info->size <<= 32;
info->size |= find_data.nFileSizeLow;
if (find_data.dwFileAttributes
& FILE_ATTRIBUTE_REPARSE_POINT) {
/* TODO: test Windows symlinks */
/* TODO: MySQL has apparently its own symlink
implementation in Windows, dbname.sym can
redirect a database directory:
REFMAN "windows-symbolic-links.html" */
info->type = OS_FILE_TYPE_LINK;
} else if (find_data.dwFileAttributes
& FILE_ATTRIBUTE_DIRECTORY) {
info->type = OS_FILE_TYPE_DIR;
} else {
/* It is probably safest to assume that all other
file types are normal. Better to check them rather
than blindly skip them. */
info->type = OS_FILE_TYPE_FILE;
}
status = 0;
} else if (GetLastError() == ERROR_NO_MORE_FILES) {
status = 1;
} else {
os_file_handle_error_no_exit(NULL, "readdir_next_file", false);
status = -1;
}
return(status);
}
/** Check that IO of specific size is possible for the file
opened with FILE_FLAG_NO_BUFFERING.
The requirement is that IO is multiple of the disk sector size.
@param[in] file file handle
@param[in] io_size expected io size
@return true - unbuffered io of requested size is possible, false otherwise.
@note: this function only works correctly with Windows 8 or later,
(GetFileInformationByHandleEx with FileStorageInfo is only supported there).
It will return true on earlier Windows version.
*/
static bool unbuffered_io_possible(HANDLE file, size_t io_size)
{
FILE_STORAGE_INFO info;
if (GetFileInformationByHandleEx(
file, FileStorageInfo, &info, sizeof(info))) {
ULONG sector_size = info.LogicalBytesPerSector;
if (sector_size)
return io_size % sector_size == 0;
}
return true;
}
/** NOTE! Use the corresponding macro os_file_create(), not directly
this function!
Opens an existing file or creates a new.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] purpose OS_FILE_AIO, if asynchronous, non-buffered I/O
is desired, OS_FILE_NORMAL, if any normal file;
NOTE that it also depends on type, os_aio_..
and srv_.. variables whether we really use async
I/O or unbuffered I/O: look in the function
source code for the exact rules
@param[in] type OS_DATA_FILE or OS_LOG_FILE
@param[in] success true if succeeded
@return handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_func(
const char* name,
ulint create_mode,
ulint purpose,
ulint type,
bool read_only,
bool* success)
{
os_file_t file;
bool retry;
bool on_error_no_exit;
bool on_error_silent;
*success = false;
DBUG_EXECUTE_IF(
"ib_create_table_fail_disk_full",
*success = false;
SetLastError(ERROR_DISK_FULL);
return(OS_FILE_CLOSED);
);
DWORD create_flag;
DWORD share_mode = srv_operation != SRV_OPERATION_NORMAL
? FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE
: FILE_SHARE_READ | FILE_SHARE_DELETE;
if (create_mode != OS_FILE_OPEN && create_mode != OS_FILE_OPEN_RAW) {
WAIT_ALLOW_WRITES();
}
on_error_no_exit = create_mode & OS_FILE_ON_ERROR_NO_EXIT
? true : false;
on_error_silent = create_mode & OS_FILE_ON_ERROR_SILENT
? true : false;
create_mode &= ~(OS_FILE_ON_ERROR_NO_EXIT | OS_FILE_ON_ERROR_SILENT);
if (create_mode == OS_FILE_OPEN_RAW) {
ut_a(!read_only);
create_flag = OPEN_EXISTING;
/* On Windows Physical devices require admin privileges and
have to have the write-share mode set. See the remarks
section for the CreateFile() function documentation in MSDN. */
share_mode |= FILE_SHARE_WRITE;
} else if (create_mode == OS_FILE_OPEN
|| create_mode == OS_FILE_OPEN_RETRY) {
create_flag = OPEN_EXISTING;
} else if (read_only) {
create_flag = OPEN_EXISTING;
} else if (create_mode == OS_FILE_CREATE) {
create_flag = CREATE_NEW;
} else if (create_mode == OS_FILE_OVERWRITE) {
create_flag = CREATE_ALWAYS;
} else {
ib::error()
<< "Unknown file create mode (" << create_mode << ") "
<< " for file '" << name << "'";
return(OS_FILE_CLOSED);
}
DWORD attributes = 0;
if (purpose == OS_FILE_AIO) {
#ifdef WIN_ASYNC_IO
/* If specified, use asynchronous (overlapped) io and no
buffering of writes in the OS */
if (srv_use_native_aio) {
attributes |= FILE_FLAG_OVERLAPPED;
}
#endif /* WIN_ASYNC_IO */
} else if (purpose == OS_FILE_NORMAL) {
/* Use default setting. */
} else {
ib::error()
<< "Unknown purpose flag (" << purpose << ") "
<< "while opening file '" << name << "'";
return(OS_FILE_CLOSED);
}
if (type == OS_LOG_FILE) {
/* There is not reason to use buffered write to logs.*/
attributes |= FILE_FLAG_NO_BUFFERING;
}
switch (srv_file_flush_method)
{
case SRV_O_DSYNC:
if (type == OS_LOG_FILE) {
/* Map O_SYNC to FILE_WRITE_THROUGH */
attributes |= FILE_FLAG_WRITE_THROUGH;
}
break;
case SRV_O_DIRECT_NO_FSYNC:
case SRV_O_DIRECT:
if (type == OS_DATA_FILE) {
attributes |= FILE_FLAG_NO_BUFFERING;
}
break;
case SRV_ALL_O_DIRECT_FSYNC:
/*Traditional Windows behavior, no buffering for any files.*/
attributes |= FILE_FLAG_NO_BUFFERING;
break;
case SRV_FSYNC:
case SRV_LITTLESYNC:
break;
case SRV_NOSYNC:
/* Let Windows cache manager handle all writes.*/
attributes &= ~(FILE_FLAG_WRITE_THROUGH | FILE_FLAG_NO_BUFFERING);
break;
default:
ut_a(false); /* unknown flush mode.*/
}
// TODO: Create a bug, this looks wrong. The flush log
// parameter is dynamic.
if (type == OS_LOG_FILE && srv_flush_log_at_trx_commit == 2) {
/* Do not use unbuffered i/o for the log files because
value 2 denotes that we do not flush the log at every
commit, but only once per second */
attributes &= ~(FILE_FLAG_WRITE_THROUGH | FILE_FLAG_NO_BUFFERING);
}
DWORD access = GENERIC_READ;
if (!read_only) {
access |= GENERIC_WRITE;
}
for (;;) {
const char *operation;
/* Use default security attributes and no template file. */
file = CreateFile(
name, access, share_mode, NULL,
create_flag, attributes, NULL);
/* If FILE_FLAG_NO_BUFFERING was set, check if this can work at all,
for expected IO sizes. Reopen without the unbuffered flag, if it is won't work*/
if ((file != INVALID_HANDLE_VALUE)
&& (attributes & FILE_FLAG_NO_BUFFERING)
&& (type == OS_LOG_FILE)
&& !unbuffered_io_possible(file, OS_FILE_LOG_BLOCK_SIZE)) {
ut_a(CloseHandle(file));
attributes &= ~FILE_FLAG_NO_BUFFERING;
create_flag = OPEN_ALWAYS;
continue;
}
*success = (file != INVALID_HANDLE_VALUE);
if (*success) {
break;
}
operation = (create_mode == OS_FILE_CREATE && !read_only) ?
"create" : "open";
if (on_error_no_exit) {
retry = os_file_handle_error_no_exit(
name, operation, on_error_silent);
}
else {
retry = os_file_handle_error(name, operation);
}
if (!retry) {
break;
}
}
if (*success && srv_use_native_aio && (attributes & FILE_FLAG_OVERLAPPED)) {
/* Bind the file handle to completion port. Completion port
might not be created yet, in some stages of backup, but
must always be there for the server.*/
HANDLE port = (type == OS_LOG_FILE) ?
log_completion_port : data_completion_port;
ut_a(port || srv_operation != SRV_OPERATION_NORMAL);
if (port) {
ut_a(CreateIoCompletionPort(file, port, 0, 0));
}
}
return(file);
}
/** NOTE! Use the corresponding macro os_file_create_simple_no_error_handling(),
not directly this function!
A simple function to open or create a file.
@param[in] name name of the file or path as a null-terminated
string
@param[in] create_mode create mode
@param[in] access_type OS_FILE_READ_ONLY, OS_FILE_READ_WRITE, or
OS_FILE_READ_ALLOW_DELETE; the last option is
used by a backup program reading the file
@param[out] success true if succeeded
@return own: handle to the file, not defined if error, error number
can be retrieved with os_file_get_last_error */
pfs_os_file_t
os_file_create_simple_no_error_handling_func(
const char* name,
ulint create_mode,
ulint access_type,
bool read_only,
bool* success)
{
os_file_t file;
*success = false;
DWORD access;
DWORD create_flag;
DWORD attributes = 0;
DWORD share_mode = srv_operation != SRV_OPERATION_NORMAL
? FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE
: FILE_SHARE_READ | FILE_SHARE_DELETE;
ut_a(name);
ut_a(!(create_mode & OS_FILE_ON_ERROR_SILENT));
ut_a(!(create_mode & OS_FILE_ON_ERROR_NO_EXIT));
if (create_mode == OS_FILE_OPEN) {
create_flag = OPEN_EXISTING;
} else if (read_only) {
create_flag = OPEN_EXISTING;
} else if (create_mode == OS_FILE_CREATE) {
create_flag = CREATE_NEW;
} else {
ib::error()
<< "Unknown file create mode (" << create_mode << ") "
<< " for file '" << name << "'";
return(OS_FILE_CLOSED);
}
if (access_type == OS_FILE_READ_ONLY) {
access = GENERIC_READ;
} else if (read_only) {
access = GENERIC_READ;
} else if (access_type == OS_FILE_READ_WRITE) {
access = GENERIC_READ | GENERIC_WRITE;
} else if (access_type == OS_FILE_READ_ALLOW_DELETE) {
ut_a(!read_only);
access = GENERIC_READ;
/*!< A backup program has to give mysqld the maximum
freedom to do what it likes with the file */
share_mode |= FILE_SHARE_DELETE | FILE_SHARE_WRITE
| FILE_SHARE_READ;
} else {
ib::error()
<< "Unknown file access type (" << access_type << ") "
<< "for file '" << name << "'";
return(OS_FILE_CLOSED);
}
file = CreateFile((LPCTSTR) name,
access,
share_mode,
NULL, // Security attributes
create_flag,
attributes,
NULL); // No template file
*success = (file != INVALID_HANDLE_VALUE);
return(file);
}
/** Deletes a file if it exists. The file has to be closed before calling this.
@param[in] name file path as a null-terminated string
@param[out] exist indicate if file pre-exist
@return true if success */
bool
os_file_delete_if_exists_func(
const char* name,
bool* exist)
{
ulint count = 0;
if (exist != NULL) {
*exist = true;
}
for (;;) {
/* In Windows, deleting an .ibd file may fail if
the file is being accessed by an external program,
such as a backup tool. */
bool ret = DeleteFile((LPCTSTR) name);
if (ret) {
return(true);
}
DWORD lasterr = GetLastError();
if (lasterr == ERROR_FILE_NOT_FOUND
|| lasterr == ERROR_PATH_NOT_FOUND) {
/* the file does not exist, this not an error */
if (exist != NULL) {
*exist = false;
}
return(true);
}
++count;
if (count > 100 && 0 == (count % 10)) {
/* Print error information */
os_file_get_last_error(true);
ib::warn() << "Delete of file '" << name << "' failed.";
}
/* Sleep for a second */
os_thread_sleep(1000000);
if (count > 2000) {
return(false);
}
}
}
/** Deletes a file. The file has to be closed before calling this.
@param[in] name File path as NUL terminated string
@return true if success */
bool
os_file_delete_func(
const char* name)
{
ulint count = 0;
for (;;) {
/* In Windows, deleting an .ibd file may fail if
the file is being accessed by an external program,
such as a backup tool. */
BOOL ret = DeleteFile((LPCTSTR) name);
if (ret) {
return(true);
}
if (GetLastError() == ERROR_FILE_NOT_FOUND) {
/* If the file does not exist, we classify this as
a 'mild' error and return */
return(false);
}
++count;
if (count > 100 && 0 == (count % 10)) {
/* print error information */
os_file_get_last_error(true);
ib::warn()
<< "Cannot delete file '" << name << "'. Is "
<< "another program accessing it?";
}
/* sleep for a second */
os_thread_sleep(1000000);
if (count > 2000) {
return(false);
}
}
ut_error;
return(false);
}
/** NOTE! Use the corresponding macro os_file_rename(), not directly this
function!
Renames a file (can also move it to another directory). It is safest that the
file is closed before calling this function.
@param[in] oldpath old file path as a null-terminated string
@param[in] newpath new file path
@return true if success */
bool
os_file_rename_func(
const char* oldpath,
const char* newpath)
{
#ifdef UNIV_DEBUG
os_file_type_t type;
bool exists;
/* New path must not exist. */
ut_ad(os_file_status(newpath, &exists, &type));
ut_ad(!exists);
/* Old path must exist. */
ut_ad(os_file_status(oldpath, &exists, &type));
ut_ad(exists);
#endif /* UNIV_DEBUG */
if (MoveFile((LPCTSTR) oldpath, (LPCTSTR) newpath)) {
return(true);
}
os_file_handle_rename_error(oldpath, newpath);
return(false);
}
/** NOTE! Use the corresponding macro os_file_close(), not directly
this function!
Closes a file handle. In case of error, error number can be retrieved with
os_file_get_last_error.
@param[in,own] file Handle to a file
@return true if success */
bool
os_file_close_func(
os_file_t file)
{
ut_a(file);
if (CloseHandle(file)) {
return(true);
}
os_file_handle_error(NULL, "close");
return(false);
}
/** Gets a file size.
@param[in] file Handle to a file
@return file size, or (os_offset_t) -1 on failure */
os_offset_t
os_file_get_size(
os_file_t file)
{
DWORD high;
DWORD low = GetFileSize(file, &high);
if (low == 0xFFFFFFFF && GetLastError() != NO_ERROR) {
return((os_offset_t) -1);
}
return(os_offset_t(low | (os_offset_t(high) << 32)));
}
/** Gets a file size.
@param[in] filename Full path to the filename to check
@return file size if OK, else set m_total_size to ~0 and m_alloc_size to
errno */
os_file_size_t
os_file_get_size(
const char* filename)
{
struct __stat64 s;
os_file_size_t file_size;
int ret = _stat64(filename, &s);
if (ret == 0) {
file_size.m_total_size = s.st_size;
DWORD low_size;
DWORD high_size;
low_size = GetCompressedFileSize(filename, &high_size);
if (low_size != INVALID_FILE_SIZE) {
file_size.m_alloc_size = high_size;
file_size.m_alloc_size <<= 32;
file_size.m_alloc_size |= low_size;
} else {
ib::error()
<< "GetCompressedFileSize("
<< filename << ", ..) failed.";
file_size.m_alloc_size = (os_offset_t) -1;
}
} else {
file_size.m_total_size = ~0;
file_size.m_alloc_size = (os_offset_t) ret;
}
return(file_size);
}
/** This function returns information about the specified file
@param[in] path pathname of the file
@param[out] stat_info information of a file in a directory
@param[in,out] statinfo information of a file in a directory
@param[in] check_rw_perm for testing whether the file can be opened
in RW mode
@param[in] read_only true if the file is opened in read-only mode
@return DB_SUCCESS if all OK */
static
dberr_t
os_file_get_status_win32(
const char* path,
os_file_stat_t* stat_info,
struct _stat64* statinfo,
bool check_rw_perm,
bool read_only)
{
int ret = _stat64(path, statinfo);
if (ret && (errno == ENOENT || errno == ENOTDIR
|| errno == ENAMETOOLONG)) {
/* file does not exist */
return(DB_NOT_FOUND);
} else if (ret) {
/* file exists, but stat call failed */
os_file_handle_error_no_exit(path, "STAT", false);
return(DB_FAIL);
} else if (_S_IFDIR & statinfo->st_mode) {
stat_info->type = OS_FILE_TYPE_DIR;
} else if (_S_IFREG & statinfo->st_mode) {
DWORD access = GENERIC_READ;
if (!read_only) {
access |= GENERIC_WRITE;
}
stat_info->type = OS_FILE_TYPE_FILE;
/* Check if we can open it in read-only mode. */
if (check_rw_perm) {
HANDLE fh;
fh = CreateFile(
(LPCTSTR) path, // File to open
access,
FILE_SHARE_READ | FILE_SHARE_WRITE
| FILE_SHARE_DELETE, // Full sharing
NULL, // Default security
OPEN_EXISTING, // Existing file only
FILE_ATTRIBUTE_NORMAL, // Normal file
NULL); // No attr. template
if (fh == INVALID_HANDLE_VALUE) {
stat_info->rw_perm = false;
} else {
stat_info->rw_perm = true;
CloseHandle(fh);
}
}
char volname[MAX_PATH];
BOOL result = GetVolumePathName(path, volname, MAX_PATH);
if (!result) {
ib::error()
<< "os_file_get_status_win32: "
<< "Failed to get the volume path name for: "
<< path
<< "- OS error number " << GetLastError();
return(DB_FAIL);
}
DWORD sectorsPerCluster;
DWORD bytesPerSector;
DWORD numberOfFreeClusters;
DWORD totalNumberOfClusters;
result = GetDiskFreeSpace(
(LPCSTR) volname,
&sectorsPerCluster,
&bytesPerSector,
&numberOfFreeClusters,
&totalNumberOfClusters);
if (!result) {
ib::error()
<< "GetDiskFreeSpace(" << volname << ",...) "
<< "failed "
<< "- OS error number " << GetLastError();
return(DB_FAIL);
}
stat_info->block_size = bytesPerSector * sectorsPerCluster;
} else {
stat_info->type = OS_FILE_TYPE_UNKNOWN;
}
return(DB_SUCCESS);
}
/**
Sets a sparse flag on Windows file.
@param[in] file file handle
@return true on success, false on error
*/
#include <versionhelpers.h>
bool os_file_set_sparse_win32(os_file_t file, bool is_sparse)
{
if (!is_sparse && !IsWindows8OrGreater()) {
/* Cannot unset sparse flag on older Windows.
Until Windows8 it is documented to produce unpredictable results,
if there are unallocated ranges in file.*/
return false;
}
DWORD temp;
FILE_SET_SPARSE_BUFFER sparse_buffer;
sparse_buffer.SetSparse = is_sparse;
return os_win32_device_io_control(file,
FSCTL_SET_SPARSE, &sparse_buffer, sizeof(sparse_buffer), 0, 0,&temp);
}
/**
Change file size on Windows.
If file is extended, the bytes between old and new EOF
are zeros.
If file is sparse, "virtual" block is added at the end of
allocated area.
If file is normal, file system allocates storage.
@param[in] pathname file path
@param[in] file file handle
@param[in] size size to preserve in bytes
@return true if success */
bool
os_file_change_size_win32(
const char* pathname,
os_file_t file,
os_offset_t size)
{
LARGE_INTEGER length;
length.QuadPart = size;
BOOL success = SetFilePointerEx(file, length, NULL, FILE_BEGIN);
if (!success) {
os_file_handle_error_no_exit(
pathname, "SetFilePointerEx", false);
} else {
success = SetEndOfFile(file);
if (!success) {
os_file_handle_error_no_exit(
pathname, "SetEndOfFile", false);
}
}
return(success);
}
/** Truncates a file at its current position.
@param[in] file Handle to be truncated
@return true if success */
bool
os_file_set_eof(
FILE* file)
{
HANDLE h = (HANDLE) _get_osfhandle(fileno(file));
return(SetEndOfFile(h));
}
/** This function can be called if one wants to post a batch of reads and
prefers an i/o-handler thread to handle them all at once later. You must
call os_aio_simulated_wake_handler_threads later to ensure the threads
are not left sleeping! */
void
os_aio_simulated_put_read_threads_to_sleep()
{
AIO::simulated_put_read_threads_to_sleep();
}
/** This function can be called if one wants to post a batch of reads and
prefers an i/o-handler thread to handle them all at once later. You must
call os_aio_simulated_wake_handler_threads later to ensure the threads
are not left sleeping! */
void
AIO::simulated_put_read_threads_to_sleep()
{
/* The idea of putting background IO threads to sleep is only for
Windows when using simulated AIO. Windows XP seems to schedule
background threads too eagerly to allow for coalescing during
readahead requests. */
if (srv_use_native_aio) {
/* We do not use simulated AIO: do nothing */
return;
}
os_aio_recommend_sleep_for_read_threads = true;
for (ulint i = 0; i < os_aio_n_segments; i++) {
AIO* array;
get_array_and_local_segment(&array, i);
if (array == s_reads) {
os_event_reset(os_aio_segment_wait_events[i]);
}
}
}
#endif /* !_WIN32*/
/** Does a syncronous read or write depending upon the type specified
In case of partial reads/writes the function tries
NUM_RETRIES_ON_PARTIAL_IO times to read/write the complete data.
@param[in] type, IO flags
@param[in] file handle to an open file
@param[out] buf buffer where to read
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@param[out] err DB_SUCCESS or error code
@return number of bytes read/written, -1 if error */
static MY_ATTRIBUTE((warn_unused_result))
ssize_t
os_file_io(
const IORequest&in_type,
os_file_t file,
void* buf,
ulint n,
os_offset_t offset,
dberr_t* err)
{
ssize_t original_n = ssize_t(n);
IORequest type = in_type;
ssize_t bytes_returned = 0;
SyncFileIO sync_file_io(file, buf, n, offset);
for (ulint i = 0; i < NUM_RETRIES_ON_PARTIAL_IO; ++i) {
ssize_t n_bytes = sync_file_io.execute(type);
/* Check for a hard error. Not much we can do now. */
if (n_bytes < 0) {
break;
} else if (n_bytes + bytes_returned == ssize_t(n)) {
bytes_returned += n_bytes;
if (offset > 0
&& !type.is_log()
&& type.is_write()
&& type.punch_hole()) {
*err = type.punch_hole(file, offset, n);
} else {
*err = DB_SUCCESS;
}
return(original_n);
}
/* Handle partial read/write. */
ut_ad(ulint(n_bytes + bytes_returned) < n);
bytes_returned += n_bytes;
if (!type.is_partial_io_warning_disabled()) {
const char* op = type.is_read()
? "read" : "written";
ib::warn()
<< n
<< " bytes should have been " << op << ". Only "
<< bytes_returned
<< " bytes " << op << ". Retrying"
<< " for the remaining bytes.";
}
/* Advance the offset and buffer by n_bytes */
sync_file_io.advance(n_bytes);
}
*err = DB_IO_ERROR;
if (!type.is_partial_io_warning_disabled()) {
ib::warn()
<< "Retry attempts for "
<< (type.is_read() ? "reading" : "writing")
<< " partial data failed.";
}
return(bytes_returned);
}
/** Does a synchronous write operation in Posix.
@param[in] type IO context
@param[in] file handle to an open file
@param[out] buf buffer from which to write
@param[in] n number of bytes to read, starting from offset
@param[in] offset file offset from the start where to read
@param[out] err DB_SUCCESS or error code
@return number of bytes written, -1 if error */
static MY_ATTRIBUTE((warn_unused_result))
ssize_t
os_file_pwrite(
const IORequest& type,
os_file_t file,
const byte* buf,
ulint n,
os_offset_t offset,
dberr_t* err)
{
ut_ad(type.validate());
ut_ad(type.is_write());
++os_n_file_writes;
const bool monitor = MONITOR_IS_ON(MONITOR_OS_PENDING_WRITES);
MONITOR_ATOMIC_INC_LOW(MONITOR_OS_PENDING_WRITES, monitor);
ssize_t n_bytes = os_file_io(type, file, const_cast<byte*>(buf),
n, offset, err);
MONITOR_ATOMIC_DEC_LOW(MONITOR_OS_PENDING_WRITES, monitor);
return(n_bytes);
}
/** NOTE! Use the corresponding macro os_file_write(), not directly
Requests a synchronous write operation.
@param[in] type IO flags
@param[in] file handle to an open file
@param[out] buf buffer from which to write
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@return error code
@retval DB_SUCCESS if the operation succeeded */
dberr_t
os_file_write_func(
const IORequest& type,
const char* name,
os_file_t file,
const void* buf,
os_offset_t offset,
ulint n)
{
dberr_t err;
ut_ad(type.validate());
ut_ad(n > 0);
WAIT_ALLOW_WRITES();
ssize_t n_bytes = os_file_pwrite(type, file, (byte*)buf, n, offset, &err);
if ((ulint) n_bytes != n && !os_has_said_disk_full) {
ib::error()
<< "Write to file " << name << " failed at offset "
<< offset << ", " << n
<< " bytes should have been written,"
" only " << n_bytes << " were written."
" Operating system error number " << IF_WIN(GetLastError(),errno) << "."
" Check that your OS and file system"
" support files of this size."
" Check also that the disk is not full"
" or a disk quota exceeded.";
#ifndef _WIN32
if (strerror(errno) != NULL) {
ib::error()
<< "Error number " << errno
<< " means '" << strerror(errno) << "'";
}
ib::info() << OPERATING_SYSTEM_ERROR_MSG;
#endif
os_has_said_disk_full = true;
}
return(err);
}
/** Does a synchronous read operation in Posix.
@param[in] type IO flags
@param[in] file handle to an open file
@param[out] buf buffer where to read
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@param[out] err DB_SUCCESS or error code
@return number of bytes read, -1 if error */
static MY_ATTRIBUTE((warn_unused_result))
ssize_t
os_file_pread(
const IORequest& type,
os_file_t file,
void* buf,
ulint n,
os_offset_t offset,
dberr_t* err)
{
ut_ad(type.is_read());
++os_n_file_reads;
const bool monitor = MONITOR_IS_ON(MONITOR_OS_PENDING_READS);
MONITOR_ATOMIC_INC_LOW(MONITOR_OS_PENDING_READS, monitor);
ssize_t n_bytes = os_file_io(type, file, buf, n, offset, err);
MONITOR_ATOMIC_DEC_LOW(MONITOR_OS_PENDING_READS, monitor);
return(n_bytes);
}
/** Requests a synchronous positioned read operation.
@return DB_SUCCESS if request was successful, false if fail
@param[in] type IO flags
@param[in] file handle to an open file
@param[out] buf buffer where to read
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@param[out] o number of bytes actually read
@param[in] exit_on_err if true then exit on error
@return DB_SUCCESS or error code */
static MY_ATTRIBUTE((warn_unused_result))
dberr_t
os_file_read_page(
const IORequest& type,
os_file_t file,
void* buf,
os_offset_t offset,
ulint n,
ulint* o,
bool exit_on_err)
{
dberr_t err;
os_bytes_read_since_printout += n;
ut_ad(type.validate());
ut_ad(n > 0);
ssize_t n_bytes = os_file_pread(type, file, buf, n, offset, &err);
if (o) {
*o = n_bytes;
}
if (ulint(n_bytes) == n || (err != DB_SUCCESS && !exit_on_err)) {
return err;
}
ib::error() << "Tried to read " << n << " bytes at offset "
<< offset << ", but was only able to read " << n_bytes;
if (!os_file_handle_error_cond_exit(
NULL, "read", exit_on_err, false)) {
ib::fatal()
<< "Cannot read from file. OS error number "
<< errno << ".";
}
if (err == DB_SUCCESS) {
err = DB_IO_ERROR;
}
return err;
}
/** Retrieves the last error number if an error occurs in a file io function.
The number should be retrieved before any other OS calls (because they may
overwrite the error number). If the number is not known to this program,
the OS error number + 100 is returned.
@param[in] report_all_errors true if we want an error printed
for all errors
@return error number, or OS error number + 100 */
ulint
os_file_get_last_error(
bool report_all_errors)
{
return(os_file_get_last_error_low(report_all_errors, false));
}
/** Handle errors for file operations.
@param[in] name name of a file or NULL
@param[in] operation operation
@param[in] should_abort whether to abort on an unknown error
@param[in] on_error_silent whether to suppress reports of non-fatal errors
@return true if we should retry the operation */
static MY_ATTRIBUTE((warn_unused_result))
bool
os_file_handle_error_cond_exit(
const char* name,
const char* operation,
bool should_abort,
bool on_error_silent)
{
ulint err;
err = os_file_get_last_error_low(false, on_error_silent);
switch (err) {
case OS_FILE_DISK_FULL:
/* We only print a warning about disk full once */
if (os_has_said_disk_full) {
return(false);
}
/* Disk full error is reported irrespective of the
on_error_silent setting. */
if (name) {
ib::error()
<< "Encountered a problem with file '"
<< name << "'";
}
ib::error()
<< "Disk is full. Try to clean the disk to free space.";
os_has_said_disk_full = true;
return(false);
case OS_FILE_AIO_RESOURCES_RESERVED:
case OS_FILE_AIO_INTERRUPTED:
return(true);
case OS_FILE_PATH_ERROR:
case OS_FILE_ALREADY_EXISTS:
case OS_FILE_ACCESS_VIOLATION:
return(false);
case OS_FILE_SHARING_VIOLATION:
os_thread_sleep(10000000); /* 10 sec */
return(true);
case OS_FILE_OPERATION_ABORTED:
case OS_FILE_INSUFFICIENT_RESOURCE:
os_thread_sleep(100000); /* 100 ms */
return(true);
default:
/* If it is an operation that can crash on error then it
is better to ignore on_error_silent and print an error message
to the log. */
if (should_abort || !on_error_silent) {
ib::error() << "File "
<< (name != NULL ? name : "(unknown)")
<< ": '" << operation << "'"
" returned OS error " << err << "."
<< (should_abort
? " Cannot continue operation" : "");
}
if (should_abort) {
abort();
}
}
return(false);
}
#ifndef _WIN32
/** Tries to disable OS caching on an opened file descriptor.
@param[in] fd file descriptor to alter
@param[in] file_name file name, used in the diagnostic message
@param[in] name "open" or "create"; used in the diagnostic
message */
void
os_file_set_nocache(
int fd MY_ATTRIBUTE((unused)),
const char* file_name MY_ATTRIBUTE((unused)),
const char* operation_name MY_ATTRIBUTE((unused)))
{
/* some versions of Solaris may not have DIRECTIO_ON */
#if defined(UNIV_SOLARIS) && defined(DIRECTIO_ON)
if (directio(fd, DIRECTIO_ON) == -1) {
int errno_save = errno;
ib::error()
<< "Failed to set DIRECTIO_ON on file "
<< file_name << "; " << operation_name << ": "
<< strerror(errno_save) << ","
" continuing anyway.";
}
#elif defined(O_DIRECT)
if (fcntl(fd, F_SETFL, O_DIRECT) == -1) {
int errno_save = errno;
static bool warning_message_printed = false;
if (errno_save == EINVAL) {
if (!warning_message_printed) {
warning_message_printed = true;
# ifdef UNIV_LINUX
ib::warn()
<< "Failed to set O_DIRECT on file"
<< file_name << "; " << operation_name
<< ": " << strerror(errno_save) << ", "
"continuing anyway. O_DIRECT is "
"known to result in 'Invalid argument' "
"on Linux on tmpfs, "
"see MySQL Bug#26662.";
# else /* UNIV_LINUX */
goto short_warning;
# endif /* UNIV_LINUX */
}
} else {
# ifndef UNIV_LINUX
short_warning:
# endif
ib::warn()
<< "Failed to set O_DIRECT on file "
<< file_name << "; " << operation_name
<< " : " << strerror(errno_save)
<< ", continuing anyway.";
}
}
#endif /* defined(UNIV_SOLARIS) && defined(DIRECTIO_ON) */
}
#endif /* _WIN32 */
/** Extend a file.
On Windows, extending a file allocates blocks for the file,
unless the file is sparse.
On Unix, we will extend the file with ftruncate(), if
file needs to be sparse. Otherwise posix_fallocate() is used
when available, and if not, binary zeroes are added to the end
of file.
@param[in] name file name
@param[in] file file handle
@param[in] size desired file size
@param[in] sparse whether to create a sparse file (no preallocating)
@return whether the operation succeeded */
bool
os_file_set_size(
const char* name,
os_file_t file,
os_offset_t size,
bool is_sparse)
{
#ifdef _WIN32
/* On Windows, changing file size works well and as expected for both
sparse and normal files.
However, 10.2 up until 10.2.9 made every file sparse in innodb,
causing NTFS fragmentation issues(MDEV-13941). We try to undo
the damage, and unsparse the file.*/
if (!is_sparse && os_is_sparse_file_supported(file)) {
if (!os_file_set_sparse_win32(file, false))
/* Unsparsing file failed. Fallback to writing binary
zeros, to avoid even higher fragmentation.*/
goto fallback;
}
return os_file_change_size_win32(name, file, size);
fallback:
#else
if (is_sparse) {
bool success = !ftruncate(file, size);
if (!success) {
ib::error() << "ftruncate of file " << name << " to "
<< size << " bytes failed with error "
<< errno;
}
return(success);
}
# ifdef HAVE_POSIX_FALLOCATE
int err;
do {
os_offset_t current_size = os_file_get_size(file);
err = current_size >= size
? 0 : posix_fallocate(file, current_size,
size - current_size);
} while (err == EINTR
&& srv_shutdown_state == SRV_SHUTDOWN_NONE);
switch (err) {
case 0:
return true;
default:
ib::error() << "preallocating "
<< size << " bytes for file " << name
<< " failed with error " << err;
/* fall through */
case EINTR:
errno = err;
return false;
case EINVAL:
/* fall back to the code below */
break;
}
# endif /* HAVE_POSIX_ALLOCATE */
#endif /* _WIN32*/
/* Write up to 1 megabyte at a time. */
ulint buf_size = ut_min(ulint(64),
ulint(size >> srv_page_size_shift))
<< srv_page_size_shift;
/* Align the buffer for possible raw i/o */
byte* buf2;
buf2 = static_cast<byte*>(ut_malloc_nokey(buf_size + srv_page_size));
byte* buf = static_cast<byte*>(ut_align(buf2, srv_page_size));
/* Write buffer full of zeros */
memset(buf, 0, buf_size);
os_offset_t current_size = os_file_get_size(file);
while (current_size < size
&& srv_shutdown_state == SRV_SHUTDOWN_NONE) {
ulint n_bytes;
if (size - current_size < (os_offset_t) buf_size) {
n_bytes = (ulint) (size - current_size);
} else {
n_bytes = buf_size;
}
dberr_t err;
IORequest request(IORequest::WRITE);
err = os_file_write(
request, name, file, buf, current_size, n_bytes);
if (err != DB_SUCCESS) {
break;
}
current_size += n_bytes;
}
ut_free(buf2);
return(current_size >= size && os_file_flush(file));
}
/** Truncate a file to a specified size in bytes.
@param[in] pathname file path
@param[in] file file to be truncated
@param[in] size size preserved in bytes
@param[in] allow_shrink whether to allow the file to become smaller
@return true if success */
bool
os_file_truncate(
const char* pathname,
os_file_t file,
os_offset_t size,
bool allow_shrink)
{
if (!allow_shrink) {
/* Do nothing if the size preserved is larger than or
equal to the current size of file */
os_offset_t size_bytes = os_file_get_size(file);
if (size >= size_bytes) {
return(true);
}
}
#ifdef _WIN32
return(os_file_change_size_win32(pathname, file, size));
#else /* _WIN32 */
return(os_file_truncate_posix(pathname, file, size));
#endif /* _WIN32 */
}
/** NOTE! Use the corresponding macro os_file_read(), not directly this
function!
Requests a synchronous positioned read operation.
@return DB_SUCCESS if request was successful, DB_IO_ERROR on failure
@param[in] type IO flags
@param[in] file handle to an open file
@param[out] buf buffer where to read
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@return error code
@retval DB_SUCCESS if the operation succeeded */
dberr_t
os_file_read_func(
const IORequest& type,
os_file_t file,
void* buf,
os_offset_t offset,
ulint n)
{
return(os_file_read_page(type, file, buf, offset, n, NULL, true));
}
/** NOTE! Use the corresponding macro os_file_read_no_error_handling(),
not directly this function!
Requests a synchronous positioned read operation.
@return DB_SUCCESS if request was successful, DB_IO_ERROR on failure
@param[in] type IO flags
@param[in] file handle to an open file
@param[out] buf buffer where to read
@param[in] offset file offset from the start where to read
@param[in] n number of bytes to read, starting from offset
@param[out] o number of bytes actually read
@return DB_SUCCESS or error code */
dberr_t
os_file_read_no_error_handling_func(
const IORequest& type,
os_file_t file,
void* buf,
os_offset_t offset,
ulint n,
ulint* o)
{
return(os_file_read_page(type, file, buf, offset, n, o, false));
}
/** Check the existence and type of the given file.
@param[in] path path name of file
@param[out] exists true if the file exists
@param[out] type Type of the file, if it exists
@return true if call succeeded */
bool
os_file_status(
const char* path,
bool* exists,
os_file_type_t* type)
{
#ifdef _WIN32
return(os_file_status_win32(path, exists, type));
#else
return(os_file_status_posix(path, exists, type));
#endif /* _WIN32 */
}
/** Free storage space associated with a section of the file.
@param[in] fh Open file handle
@param[in] off Starting offset (SEEK_SET)
@param[in] len Size of the hole
@return DB_SUCCESS or error code */
dberr_t
os_file_punch_hole(
os_file_t fh,
os_offset_t off,
os_offset_t len)
{
dberr_t err;
#ifdef _WIN32
err = os_file_punch_hole_win32(fh, off, len);
#else
err = os_file_punch_hole_posix(fh, off, len);
#endif /* _WIN32 */
return (err);
}
/** Free storage space associated with a section of the file.
@param[in] fh Open file handle
@param[in] off Starting offset (SEEK_SET)
@param[in] len Size of the hole
@return DB_SUCCESS or error code */
dberr_t
IORequest::punch_hole(os_file_t fh, os_offset_t off, ulint len)
{
/* In this debugging mode, we act as if punch hole is supported,
and then skip any calls to actually punch a hole here.
In this way, Transparent Page Compression is still being tested. */
DBUG_EXECUTE_IF("ignore_punch_hole",
return(DB_SUCCESS);
);
ulint trim_len = get_trim_length(len);
if (trim_len == 0) {
return(DB_SUCCESS);
}
off += len;
/* Check does file system support punching holes for this
tablespace. */
if (!should_punch_hole()) {
return DB_IO_NO_PUNCH_HOLE;
}
dberr_t err = os_file_punch_hole(fh, off, trim_len);
if (err == DB_SUCCESS) {
srv_stats.page_compressed_trim_op.inc();
} else {
/* If punch hole is not supported,
set space so that it is not used. */
if (err == DB_IO_NO_PUNCH_HOLE) {
space_no_punch_hole();
err = DB_SUCCESS;
}
}
return (err);
}
/** Check if the file system supports sparse files.
Warning: On POSIX systems we try and punch a hole from offset 0 to
the system configured page size. This should only be called on an empty
file.
@param[in] fh File handle for the file - if opened
@return true if the file system supports sparse files */
bool
os_is_sparse_file_supported(os_file_t fh)
{
/* In this debugging mode, we act as if punch hole is supported,
then we skip any calls to actually punch a hole. In this way,
Transparent Page Compression is still being tested. */
DBUG_EXECUTE_IF("ignore_punch_hole",
return(true);
);
#ifdef _WIN32
FILE_ATTRIBUTE_TAG_INFO info;
if (GetFileInformationByHandleEx(fh, FileAttributeTagInfo,
&info, (DWORD)sizeof(info))) {
if (info.FileAttributes != INVALID_FILE_ATTRIBUTES) {
return (info.FileAttributes & FILE_ATTRIBUTE_SPARSE_FILE) != 0;
}
}
return false;
#else
dberr_t err;
/* We don't know the FS block size, use the sector size. The FS
will do the magic. */
err = os_file_punch_hole_posix(fh, 0, srv_page_size);
return(err == DB_SUCCESS);
#endif /* _WIN32 */
}
/** This function returns information about the specified file
@param[in] path pathname of the file
@param[out] stat_info information of a file in a directory
@param[in] check_rw_perm for testing whether the file can be opened
in RW mode
@param[in] read_only true if file is opened in read-only mode
@return DB_SUCCESS if all OK */
dberr_t
os_file_get_status(
const char* path,
os_file_stat_t* stat_info,
bool check_rw_perm,
bool read_only)
{
dberr_t ret;
#ifdef _WIN32
struct _stat64 info;
ret = os_file_get_status_win32(
path, stat_info, &info, check_rw_perm, read_only);
#else
struct stat info;
ret = os_file_get_status_posix(
path, stat_info, &info, check_rw_perm, read_only);
#endif /* _WIN32 */
if (ret == DB_SUCCESS) {
stat_info->ctime = info.st_ctime;
stat_info->atime = info.st_atime;
stat_info->mtime = info.st_mtime;
stat_info->size = info.st_size;
}
return(ret);
}
/**
Waits for an AIO operation to complete. This function is used to wait the
for completed requests. The aio array of pending requests is divided
into segments. The thread specifies which segment or slot it wants to wait
for. NOTE: this function will also take care of freeing the aio slot,
therefore no other thread is allowed to do the freeing!
@param[in] segment The number of the segment in the aio arrays to
wait for; segment 0 is the ibuf I/O thread,
segment 1 the log I/O thread, then follow the
non-ibuf read threads, and as the last are the
non-ibuf write threads; if this is
ULINT_UNDEFINED, then it means that sync AIO
is used, and this parameter is ignored
@param[out] m1 the messages passed with the AIO request; note
that also in the case where the AIO operation
failed, these output parameters are valid and
can be used to restart the operation,
for example
@param[out] m2 callback message
@param[out] type OS_FILE_WRITE or ..._READ
@return DB_SUCCESS or error code */
dberr_t
os_aio_handler(
ulint segment,
fil_node_t** m1,
void** m2,
IORequest* request)
{
dberr_t err;
if (srv_use_native_aio) {
srv_set_io_thread_op_info(segment, "native aio handle");
#ifdef WIN_ASYNC_IO
err = os_aio_windows_handler(segment, 0, m1, m2, request);
#elif defined(LINUX_NATIVE_AIO)
err = os_aio_linux_handler(segment, m1, m2, request);
#else
ut_error;
err = DB_ERROR; /* Eliminate compiler warning */
#endif /* WIN_ASYNC_IO */
} else {
srv_set_io_thread_op_info(segment, "simulated aio handle");
err = os_aio_simulated_handler(segment, m1, m2, request);
}
return(err);
}
#ifdef WIN_ASYNC_IO
static HANDLE new_completion_port()
{
HANDLE h = CreateIoCompletionPort(INVALID_HANDLE_VALUE, 0, 0, 0);
ut_a(h);
return h;
}
#endif
/** Constructor
@param[in] id The latch ID
@param[in] n Number of AIO slots
@param[in] segments Number of segments */
AIO::AIO(
latch_id_t id,
ulint n,
ulint segments)
:
m_slots(n),
m_n_segments(segments),
m_n_reserved()
# ifdef LINUX_NATIVE_AIO
,m_aio_ctx(),
m_events(m_slots.size())
# endif /* LINUX_NATIVE_AIO */
#ifdef WIN_ASYNC_IO
,m_completion_port(new_completion_port())
#endif
{
ut_a(n > 0);
ut_a(m_n_segments > 0);
mutex_create(id, &m_mutex);
m_not_full = os_event_create("aio_not_full");
m_is_empty = os_event_create("aio_is_empty");
memset((void*)&m_slots[0], 0x0, sizeof(m_slots[0]) * m_slots.size());
#ifdef LINUX_NATIVE_AIO
memset(&m_events[0], 0x0, sizeof(m_events[0]) * m_events.size());
#endif /* LINUX_NATIVE_AIO */
os_event_set(m_is_empty);
}
/** Initialise the slots */
dberr_t
AIO::init_slots()
{
for (ulint i = 0; i < m_slots.size(); ++i) {
Slot& slot = m_slots[i];
slot.pos = static_cast<uint16_t>(i);
slot.is_reserved = false;
#ifdef WIN_ASYNC_IO
slot.array = this;
#elif defined(LINUX_NATIVE_AIO)
slot.ret = 0;
slot.n_bytes = 0;
memset(&slot.control, 0x0, sizeof(slot.control));
#endif /* WIN_ASYNC_IO */
}
return(DB_SUCCESS);
}
#ifdef LINUX_NATIVE_AIO
/** Initialise the Linux Native AIO interface */
dberr_t
AIO::init_linux_native_aio()
{
/* Initialize the io_context array. One io_context
per segment in the array. */
ut_a(m_aio_ctx == NULL);
m_aio_ctx = static_cast<io_context**>(
ut_zalloc_nokey(m_n_segments * sizeof(*m_aio_ctx)));
if (m_aio_ctx == NULL) {
return(DB_OUT_OF_MEMORY);
}
io_context** ctx = m_aio_ctx;
ulint max_events = slots_per_segment();
for (ulint i = 0; i < m_n_segments; ++i, ++ctx) {
if (!linux_create_io_ctx(max_events, ctx)) {
/* If something bad happened during aio setup
we disable linux native aio.
The disadvantage will be a small memory leak
at shutdown but that's ok compared to a crash
or a not working server.
This frequently happens when running the test suite
with many threads on a system with low fs.aio-max-nr!
*/
ib::warn()
<< "Warning: Linux Native AIO disabled "
<< "because _linux_create_io_ctx() "
<< "failed. To get rid of this warning you can "
<< "try increasing system "
<< "fs.aio-max-nr to 1048576 or larger or "
<< "setting innodb_use_native_aio = 0 in my.cnf";
ut_free(m_aio_ctx);
m_aio_ctx = 0;
srv_use_native_aio = FALSE;
return(DB_SUCCESS);
}
}
return(DB_SUCCESS);
}
#endif /* LINUX_NATIVE_AIO */
/** Initialise the array */
dberr_t
AIO::init()
{
ut_a(!m_slots.empty());
if (srv_use_native_aio) {
#ifdef LINUX_NATIVE_AIO
dberr_t err = init_linux_native_aio();
if (err != DB_SUCCESS) {
return(err);
}
#endif /* LINUX_NATIVE_AIO */
}
return(init_slots());
}
/** Creates an aio wait array. Note that we return NULL in case of failure.
We don't care about freeing memory here because we assume that a
failure will result in server refusing to start up.
@param[in] id Latch ID
@param[in] n maximum number of pending AIO operations
allowed; n must be divisible by m_n_segments
@param[in] n_segments number of segments in the AIO array
@return own: AIO array, NULL on failure */
AIO*
AIO::create(
latch_id_t id,
ulint n,
ulint n_segments)
{
if ((n % n_segments)) {
ib::error()
<< "Maximum number of AIO operations must be "
<< "divisible by number of segments";
return(NULL);
}
AIO* array = UT_NEW_NOKEY(AIO(id, n, n_segments));
if (array != NULL && array->init() != DB_SUCCESS) {
UT_DELETE(array);
array = NULL;
}
return(array);
}
/** AIO destructor */
AIO::~AIO()
{
mutex_destroy(&m_mutex);
os_event_destroy(m_not_full);
os_event_destroy(m_is_empty);
#if defined(LINUX_NATIVE_AIO)
if (srv_use_native_aio) {
m_events.clear();
ut_free(m_aio_ctx);
}
#endif /* LINUX_NATIVE_AIO */
#if defined(WIN_ASYNC_IO)
CloseHandle(m_completion_port);
#endif
m_slots.clear();
}
/** Initializes the asynchronous io system. Creates one array each for ibuf
and log i/o. Also creates one array each for read and write where each
array is divided logically into n_readers and n_writers
respectively. The caller must create an i/o handler thread for each
segment in these arrays. This function also creates the sync array.
No i/o handler thread needs to be created for that
@param[in] n_per_seg maximum number of pending aio
operations allowed per segment
@param[in] n_readers number of reader threads
@param[in] n_writers number of writer threads
@param[in] n_slots_sync number of slots in the sync aio array
@return true if the AIO sub-system was started successfully */
bool
AIO::start(
ulint n_per_seg,
ulint n_readers,
ulint n_writers,
ulint n_slots_sync)
{
#if defined(LINUX_NATIVE_AIO)
/* Check if native aio is supported on this system and tmpfs */
if (srv_use_native_aio && !is_linux_native_aio_supported()) {
ib::warn() << "Linux Native AIO disabled.";
srv_use_native_aio = FALSE;
}
#endif /* LINUX_NATIVE_AIO */
srv_reset_io_thread_op_info();
s_reads = create(
LATCH_ID_OS_AIO_READ_MUTEX, n_readers * n_per_seg, n_readers);
if (s_reads == NULL) {
return(false);
}
ulint start = srv_read_only_mode ? 0 : 2;
ulint n_segs = n_readers + start;
/* 0 is the ibuf segment and 1 is the redo log segment. */
for (ulint i = start; i < n_segs; ++i) {
ut_a(i < SRV_MAX_N_IO_THREADS);
srv_io_thread_function[i] = "read thread";
}
ulint n_segments = n_readers;
if (!srv_read_only_mode) {
s_ibuf = create(LATCH_ID_OS_AIO_IBUF_MUTEX, n_per_seg, 1);
if (s_ibuf == NULL) {
return(false);
}
++n_segments;
srv_io_thread_function[0] = "insert buffer thread";
s_log = create(LATCH_ID_OS_AIO_LOG_MUTEX, n_per_seg, 1);
if (s_log == NULL) {
return(false);
}
++n_segments;
srv_io_thread_function[1] = "log thread";
} else {
s_ibuf = s_log = NULL;
}
s_writes = create(
LATCH_ID_OS_AIO_WRITE_MUTEX, n_writers * n_per_seg, n_writers);
if (s_writes == NULL) {
return(false);
}
#ifdef WIN_ASYNC_IO
data_completion_port = s_writes->m_completion_port;
log_completion_port =
s_log ? s_log->m_completion_port : data_completion_port;
#endif
n_segments += n_writers;
for (ulint i = start + n_readers; i < n_segments; ++i) {
ut_a(i < SRV_MAX_N_IO_THREADS);
srv_io_thread_function[i] = "write thread";
}
ut_ad(n_segments >= static_cast<ulint>(srv_read_only_mode ? 2 : 4));
s_sync = create(LATCH_ID_OS_AIO_SYNC_MUTEX, n_slots_sync, 1);
if (s_sync == NULL) {
return(false);
}
os_aio_n_segments = n_segments;
os_aio_validate();
os_last_printout = ut_time();
if (srv_use_native_aio) {
return(true);
}
os_aio_segment_wait_events = static_cast<os_event_t*>(
ut_zalloc_nokey(
n_segments * sizeof *os_aio_segment_wait_events));
if (os_aio_segment_wait_events == NULL) {
return(false);
}
for (ulint i = 0; i < n_segments; ++i) {
os_aio_segment_wait_events[i] = os_event_create(0);
}
return(true);
}
/** Free the AIO arrays */
void
AIO::shutdown()
{
UT_DELETE(s_ibuf);
s_ibuf = NULL;
UT_DELETE(s_log);
s_log = NULL;
UT_DELETE(s_writes);
s_writes = NULL;
UT_DELETE(s_sync);
s_sync = NULL;
UT_DELETE(s_reads);
s_reads = NULL;
}
/** Initializes the asynchronous io system. Creates one array each for ibuf
and log i/o. Also creates one array each for read and write where each
array is divided logically into n_readers and n_writers
respectively. The caller must create an i/o handler thread for each
segment in these arrays. This function also creates the sync array.
No i/o handler thread needs to be created for that
@param[in] n_readers number of reader threads
@param[in] n_writers number of writer threads
@param[in] n_slots_sync number of slots in the sync aio array */
bool
os_aio_init(
ulint n_readers,
ulint n_writers,
ulint n_slots_sync)
{
/* Maximum number of pending aio operations allowed per segment */
ulint limit = 8 * OS_AIO_N_PENDING_IOS_PER_THREAD;
return(AIO::start(limit, n_readers, n_writers, n_slots_sync));
}
/** Frees the asynchronous io system. */
void
os_aio_free()
{
AIO::shutdown();
ut_ad(!os_aio_segment_wait_events || !srv_use_native_aio);
ut_ad(srv_use_native_aio || os_aio_segment_wait_events
|| !srv_was_started);
if (!srv_use_native_aio && os_aio_segment_wait_events) {
for (ulint i = 0; i < os_aio_n_segments; i++) {
os_event_destroy(os_aio_segment_wait_events[i]);
}
ut_free(os_aio_segment_wait_events);
os_aio_segment_wait_events = 0;
}
os_aio_n_segments = 0;
}
/** Wakes up all async i/o threads so that they know to exit themselves in
shutdown. */
void
os_aio_wake_all_threads_at_shutdown()
{
#ifdef WIN_ASYNC_IO
AIO::wake_at_shutdown();
#elif defined(LINUX_NATIVE_AIO)
/* When using native AIO interface the io helper threads
wait on io_getevents with a timeout value of 500ms. At
each wake up these threads check the server status.
No need to do anything to wake them up. */
#endif /* !WIN_ASYNC_AIO */
if (srv_use_native_aio) {
return;
}
/* This loop wakes up all simulated ai/o threads */
for (ulint i = 0; i < os_aio_n_segments; ++i) {
os_event_set(os_aio_segment_wait_events[i]);
}
}
/** Waits until there are no pending writes in AIO::s_writes. There can
be other, synchronous, pending writes. */
void
os_aio_wait_until_no_pending_writes()
{
AIO::wait_until_no_pending_writes();
}
/** Calculates segment number for a slot.
@param[in] array AIO wait array
@param[in] slot slot in this array
@return segment number (which is the number used by, for example,
I/O-handler threads) */
ulint
AIO::get_segment_no_from_slot(
const AIO* array,
const Slot* slot)
{
ulint segment;
ulint seg_len;
if (array == s_ibuf) {
ut_ad(!srv_read_only_mode);
segment = IO_IBUF_SEGMENT;
} else if (array == s_log) {
ut_ad(!srv_read_only_mode);
segment = IO_LOG_SEGMENT;
} else if (array == s_reads) {
seg_len = s_reads->slots_per_segment();
segment = (srv_read_only_mode ? 0 : 2) + slot->pos / seg_len;
} else {
ut_a(array == s_writes);
seg_len = s_writes->slots_per_segment();
segment = s_reads->m_n_segments
+ (srv_read_only_mode ? 0 : 2) + slot->pos / seg_len;
}
return(segment);
}
/** Requests for a slot in the aio array. If no slot is available, waits until
not_full-event becomes signaled.
@param[in] type IO context
@param[in,out] m1 message to be passed along with the AIO
operation
@param[in,out] m2 message to be passed along with the AIO
operation
@param[in] file file handle
@param[in] name name of the file or path as a NUL-terminated
string
@param[in,out] buf buffer where to read or from which to write
@param[in] offset file offset, where to read from or start writing
@param[in] len length of the block to read or write
@return pointer to slot */
Slot*
AIO::reserve_slot(
const IORequest& type,
fil_node_t* m1,
void* m2,
pfs_os_file_t file,
const char* name,
void* buf,
os_offset_t offset,
ulint len)
{
#ifdef WIN_ASYNC_IO
ut_a((len & 0xFFFFFFFFUL) == len);
#endif /* WIN_ASYNC_IO */
/* No need of a mutex. Only reading constant fields */
ulint slots_per_seg;
ut_ad(type.validate());
slots_per_seg = slots_per_segment();
/* We attempt to keep adjacent blocks in the same local
segment. This can help in merging IO requests when we are
doing simulated AIO */
ulint local_seg;
local_seg = (offset >> (srv_page_size_shift + 6)) % m_n_segments;
for (;;) {
acquire();
if (m_n_reserved != m_slots.size()) {
break;
}
release();
if (!srv_use_native_aio) {
/* If the handler threads are suspended,
wake them so that we get more slots */
os_aio_simulated_wake_handler_threads();
}
os_event_wait(m_not_full);
}
ulint counter = 0;
Slot* slot = NULL;
/* We start our search for an available slot from our preferred
local segment and do a full scan of the array. We are
guaranteed to find a slot in full scan. */
for (ulint i = local_seg * slots_per_seg;
counter < m_slots.size();
++i, ++counter) {
i %= m_slots.size();
slot = at(i);
if (slot->is_reserved == false) {
break;
}
}
/* We MUST always be able to get hold of a reserved slot. */
ut_a(counter < m_slots.size());
ut_a(slot->is_reserved == false);
++m_n_reserved;
if (m_n_reserved == 1) {
os_event_reset(m_is_empty);
}
if (m_n_reserved == m_slots.size()) {
os_event_reset(m_not_full);
}
slot->is_reserved = true;
slot->reservation_time = ut_time();
slot->m1 = m1;
slot->m2 = m2;
slot->file = file;
slot->name = name;
#ifdef _WIN32
slot->len = static_cast<DWORD>(len);
#else
slot->len = len;
#endif /* _WIN32 */
slot->type = type;
slot->buf = static_cast<byte*>(buf);
slot->ptr = slot->buf;
slot->offset = offset;
slot->err = DB_SUCCESS;
slot->original_len = static_cast<uint32>(len);
slot->io_already_done = false;
slot->buf = static_cast<byte*>(buf);
#ifdef WIN_ASYNC_IO
{
OVERLAPPED* control;
control = &slot->control;
control->Offset = (DWORD) offset & 0xFFFFFFFF;
control->OffsetHigh = (DWORD) (offset >> 32);
}
#elif defined(LINUX_NATIVE_AIO)
/* If we are not using native AIO skip this part. */
if (srv_use_native_aio) {
off_t aio_offset;
/* Check if we are dealing with 64 bit arch.
If not then make sure that offset fits in 32 bits. */
aio_offset = (off_t) offset;
ut_a(sizeof(aio_offset) >= sizeof(offset)
|| ((os_offset_t) aio_offset) == offset);
struct iocb* iocb = &slot->control;
if (type.is_read()) {
io_prep_pread(
iocb, file, slot->ptr, slot->len, aio_offset);
} else {
ut_ad(type.is_write());
io_prep_pwrite(
iocb, file, slot->ptr, slot->len, aio_offset);
}
iocb->data = slot;
slot->n_bytes = 0;
slot->ret = 0;
}
#endif /* LINUX_NATIVE_AIO */
release();
return(slot);
}
/** Wakes up a simulated aio i/o-handler thread if it has something to do.
@param[in] global_segment The number of the segment in the AIO arrays */
void
AIO::wake_simulated_handler_thread(ulint global_segment)
{
ut_ad(!srv_use_native_aio);
AIO* array;
ulint segment = get_array_and_local_segment(&array, global_segment);
array->wake_simulated_handler_thread(global_segment, segment);
}
/** Wakes up a simulated AIO I/O-handler thread if it has something to do
for a local segment in the AIO array.
@param[in] global_segment The number of the segment in the AIO arrays
@param[in] segment The local segment in the AIO array */
void
AIO::wake_simulated_handler_thread(ulint global_segment, ulint segment)
{
ut_ad(!srv_use_native_aio);
ulint n = slots_per_segment();
ulint offset = segment * n;
/* Look through n slots after the segment * n'th slot */
acquire();
const Slot* slot = at(offset);
for (ulint i = 0; i < n; ++i, ++slot) {
if (slot->is_reserved) {
/* Found an i/o request */
release();
os_event_t event;
event = os_aio_segment_wait_events[global_segment];
os_event_set(event);
return;
}
}
release();
}
/** Wakes up simulated aio i/o-handler threads if they have something to do. */
void
os_aio_simulated_wake_handler_threads()
{
if (srv_use_native_aio) {
/* We do not use simulated aio: do nothing */
return;
}
os_aio_recommend_sleep_for_read_threads = false;
for (ulint i = 0; i < os_aio_n_segments; i++) {
AIO::wake_simulated_handler_thread(i);
}
}
/** Select the IO slot array
@param[in,out] type Type of IO, READ or WRITE
@param[in] read_only true if running in read-only mode
@param[in] mode IO mode
@return slot array or NULL if invalid mode specified */
AIO*
AIO::select_slot_array(IORequest& type, bool read_only, ulint mode)
{
AIO* array;
ut_ad(type.validate());
switch (mode) {
case OS_AIO_NORMAL:
array = type.is_read() ? AIO::s_reads : AIO::s_writes;
break;
case OS_AIO_IBUF:
ut_ad(type.is_read());
/* Reduce probability of deadlock bugs in connection with ibuf:
do not let the ibuf i/o handler sleep */
type.clear_do_not_wake();
array = read_only ? AIO::s_reads : AIO::s_ibuf;
break;
case OS_AIO_LOG:
array = read_only ? AIO::s_reads : AIO::s_log;
break;
case OS_AIO_SYNC:
array = AIO::s_sync;
#if defined(LINUX_NATIVE_AIO)
/* In Linux native AIO we don't use sync IO array. */
ut_a(!srv_use_native_aio);
#endif /* LINUX_NATIVE_AIO */
break;
default:
ut_error;
array = NULL; /* Eliminate compiler warning */
}
return(array);
}
#ifdef WIN_ASYNC_IO
/** This function is only used in Windows asynchronous i/o.
Waits for an aio operation to complete. This function is used to wait the
for completed requests. The aio array of pending requests is divided
into segments. The thread specifies which segment or slot it wants to wait
for. NOTE: this function will also take care of freeing the aio slot,
therefore no other thread is allowed to do the freeing!
@param[in] segment The number of the segment in the aio arrays to
wait for; segment 0 is the ibuf I/O thread,
segment 1 the log I/O thread, then follow the
non-ibuf read threads, and as the last are the
non-ibuf write threads; if this is
ULINT_UNDEFINED, then it means that sync AIO
is used, and this parameter is ignored
@param[in] pos this parameter is used only in sync AIO:
wait for the aio slot at this position
@param[out] m1 the messages passed with the AIO request; note
that also in the case where the AIO operation
failed, these output parameters are valid and
can be used to restart the operation,
for example
@param[out] m2 callback message
@param[out] type OS_FILE_WRITE or ..._READ
@return DB_SUCCESS or error code */
static
dberr_t
os_aio_windows_handler(
ulint segment,
ulint pos,
fil_node_t** m1,
void** m2,
IORequest* type)
{
Slot* slot= 0;
dberr_t err;
BOOL ret;
ULONG_PTR key;
ut_a(segment != ULINT_UNDEFINED);
/* NOTE! We only access constant fields in os_aio_array. Therefore
we do not have to acquire the protecting mutex yet */
ut_ad(os_aio_validate_skip());
AIO *my_array;
AIO::get_array_and_local_segment(&my_array, segment);
HANDLE port = my_array->m_completion_port;
ut_ad(port);
for (;;) {
DWORD len;
ret = GetQueuedCompletionStatus(port, &len, &key,
(OVERLAPPED **)&slot, INFINITE);
/* If shutdown key was received, repost the shutdown message and exit */
if (ret && key == IOCP_SHUTDOWN_KEY) {
PostQueuedCompletionStatus(port, 0, key, NULL);
*m1 = NULL;
*m2 = NULL;
return (DB_SUCCESS);
}
ut_a(slot);
if (!ret) {
/* IO failed */
break;
}
slot->n_bytes= len;
ut_a(slot->array);
HANDLE slot_port = slot->array->m_completion_port;
if (slot_port != port) {
/* there are no redirections between data and log */
ut_ad(port == data_completion_port);
ut_ad(slot_port != log_completion_port);
/*
Redirect completions to the dedicated completion port
and threads.
"Write array" threads receive write,read and ibuf
notifications, read and ibuf completions are redirected.
Forwarding IO completion this way costs a context switch,
and this seems tolerable since asynchronous reads are by
far less frequent.
*/
ut_a(PostQueuedCompletionStatus(slot_port,
len, key, &slot->control));
}
else {
break;
}
}
ut_a(slot->is_reserved);
*m1 = slot->m1;
*m2 = slot->m2;
*type = slot->type;
bool retry = false;
if (ret && slot->n_bytes == slot->len) {
err = DB_SUCCESS;
} else if (os_file_handle_error(slot->name, "Windows aio")) {
retry = true;
} else {
err = DB_IO_ERROR;
}
if (retry) {
/* Retry failed read/write operation synchronously. */
#ifdef UNIV_PFS_IO
/* This read/write does not go through os_file_read
and os_file_write APIs, need to register with
performance schema explicitly here. */
PSI_file_locker_state state;
struct PSI_file_locker* locker = NULL;
register_pfs_file_io_begin(
&state, locker, slot->file, slot->len,
slot->type.is_write()
? PSI_FILE_WRITE : PSI_FILE_READ, __FILE__, __LINE__);
#endif /* UNIV_PFS_IO */
ut_a((slot->len & 0xFFFFFFFFUL) == slot->len);
ssize_t n_bytes = SyncFileIO::execute(slot);
#ifdef UNIV_PFS_IO
register_pfs_file_io_end(locker, slot->len);
#endif /* UNIV_PFS_IO */
err = (n_bytes == slot->len) ? DB_SUCCESS : DB_IO_ERROR;
}
if (err == DB_SUCCESS) {
err = AIOHandler::post_io_processing(slot);
}
slot->array->release_with_mutex(slot);
if (srv_shutdown_state == SRV_SHUTDOWN_EXIT_THREADS
&& !buf_page_cleaner_is_active
&& os_aio_all_slots_free()) {
/* Last IO, wakeup other io threads */
AIO::wake_at_shutdown();
}
return(err);
}
#endif /* WIN_ASYNC_IO */
/**
NOTE! Use the corresponding macro os_aio(), not directly this function!
Requests an asynchronous i/o operation.
@param[in,out] type IO request context
@param[in] mode IO mode
@param[in] name Name of the file or path as NUL terminated
string
@param[in] file Open file handle
@param[out] buf buffer where to read
@param[in] offset file offset where to read
@param[in] n number of bytes to read
@param[in] read_only if true read only mode checks are enforced
@param[in,out] m1 Message for the AIO handler, (can be used to
identify a completed AIO operation); ignored
if mode is OS_AIO_SYNC
@param[in,out] m2 message for the AIO handler (can be used to
identify a completed AIO operation); ignored
if mode is OS_AIO_SYNC
@return DB_SUCCESS or error code */
dberr_t
os_aio_func(
IORequest& type,
ulint mode,
const char* name,
pfs_os_file_t file,
void* buf,
os_offset_t offset,
ulint n,
bool read_only,
fil_node_t* m1,
void* m2)
{
#ifdef WIN_ASYNC_IO
BOOL ret = TRUE;
#endif /* WIN_ASYNC_IO */
ut_ad(n > 0);
ut_ad((n % OS_FILE_LOG_BLOCK_SIZE) == 0);
ut_ad((offset % OS_FILE_LOG_BLOCK_SIZE) == 0);
ut_ad(os_aio_validate_skip());
#ifdef WIN_ASYNC_IO
ut_ad((n & 0xFFFFFFFFUL) == n);
#endif /* WIN_ASYNC_IO */
DBUG_EXECUTE_IF("ib_os_aio_func_io_failure_28",
mode = OS_AIO_SYNC; os_has_said_disk_full = FALSE;);
if (mode == OS_AIO_SYNC) {
if (type.is_read()) {
return(os_file_read_func(type, file, buf, offset, n));
}
ut_ad(type.is_write());
return(os_file_write_func(type, name, file, buf, offset, n));
}
try_again:
AIO* array;
array = AIO::select_slot_array(type, read_only, mode);
Slot* slot;
slot = array->reserve_slot(type, m1, m2, file, name, buf, offset, n);
if (type.is_read()) {
if (srv_use_native_aio) {
++os_n_file_reads;
os_bytes_read_since_printout += n;
#ifdef WIN_ASYNC_IO
ret = ReadFile(
file, slot->ptr, slot->len,
NULL, &slot->control);
#elif defined(LINUX_NATIVE_AIO)
if (!array->linux_dispatch(slot)) {
goto err_exit;
}
#endif /* WIN_ASYNC_IO */
} else if (type.is_wake()) {
AIO::wake_simulated_handler_thread(
AIO::get_segment_no_from_slot(array, slot));
}
} else if (type.is_write()) {
if (srv_use_native_aio) {
++os_n_file_writes;
#ifdef WIN_ASYNC_IO
ret = WriteFile(
file, slot->ptr, slot->len,
NULL, &slot->control);
#elif defined(LINUX_NATIVE_AIO)
if (!array->linux_dispatch(slot)) {
goto err_exit;
}
#endif /* WIN_ASYNC_IO */
} else if (type.is_wake()) {
AIO::wake_simulated_handler_thread(
AIO::get_segment_no_from_slot(array, slot));
}
} else {
ut_error;
}
#ifdef WIN_ASYNC_IO
if (ret || (GetLastError() == ERROR_IO_PENDING)) {
/* aio completed or was queued successfully! */
return(DB_SUCCESS);
}
goto err_exit;
#endif /* WIN_ASYNC_IO */
/* AIO request was queued successfully! */
return(DB_SUCCESS);
#if defined LINUX_NATIVE_AIO || defined WIN_ASYNC_IO
err_exit:
#endif /* LINUX_NATIVE_AIO || WIN_ASYNC_IO */
array->release_with_mutex(slot);
if (os_file_handle_error(
name, type.is_read() ? "aio read" : "aio write")) {
goto try_again;
}
return(DB_IO_ERROR);
}
/** Simulated AIO handler for reaping IO requests */
class SimulatedAIOHandler {
public:
/** Constructor
@param[in,out] array The AIO array
@param[in] segment Local segment in the array */
SimulatedAIOHandler(AIO* array, ulint segment)
:
m_oldest(),
m_n_elems(),
m_lowest_offset(IB_UINT64_MAX),
m_array(array),
m_n_slots(),
m_segment(segment),
m_ptr(),
m_buf()
{
ut_ad(m_segment < 100);
m_slots.resize(OS_AIO_MERGE_N_CONSECUTIVE);
}
/** Destructor */
~SimulatedAIOHandler()
{
if (m_ptr != NULL) {
ut_free(m_ptr);
}
}
/** Reset the state of the handler
@param[in] n_slots Number of pending AIO operations supported */
void init(ulint n_slots)
{
m_oldest = 0;
m_n_elems = 0;
m_n_slots = n_slots;
m_lowest_offset = IB_UINT64_MAX;
if (m_ptr != NULL) {
ut_free(m_ptr);
m_ptr = m_buf = NULL;
}
m_slots[0] = NULL;
}
/** Check if there is a slot for which the i/o has already been done
@param[out] n_reserved Number of reserved slots
@return the first completed slot that is found. */
Slot* check_completed(ulint* n_reserved)
{
ulint offset = m_segment * m_n_slots;
*n_reserved = 0;
Slot* slot;
slot = m_array->at(offset);
for (ulint i = 0; i < m_n_slots; ++i, ++slot) {
if (slot->is_reserved) {
if (slot->io_already_done) {
ut_a(slot->is_reserved);
return(slot);
}
++*n_reserved;
}
}
return(NULL);
}
/** If there are at least 2 seconds old requests, then pick the
oldest one to prevent starvation. If several requests have the
same age, then pick the one at the lowest offset.
@return true if request was selected */
bool select()
{
if (!select_oldest()) {
return(select_lowest_offset());
}
return(true);
}
/** Check if there are several consecutive blocks
to read or write. Merge them if found. */
void merge()
{
/* if m_n_elems != 0, then we have assigned
something valid to consecutive_ios[0] */
ut_ad(m_n_elems != 0);
ut_ad(first_slot() != NULL);
Slot* slot = first_slot();
while (!merge_adjacent(slot)) {
/* No op */
}
}
/** We have now collected n_consecutive I/O requests
in the array; allocate a single buffer which can hold
all data, and perform the I/O
@return the length of the buffer */
ulint allocate_buffer()
MY_ATTRIBUTE((warn_unused_result))
{
ulint len;
Slot* slot = first_slot();
ut_ad(m_ptr == NULL);
if (slot->type.is_read() && m_n_elems > 1) {
len = 0;
for (ulint i = 0; i < m_n_elems; ++i) {
len += m_slots[i]->len;
}
m_ptr = static_cast<byte*>(
ut_malloc_nokey(len + srv_page_size));
m_buf = static_cast<byte*>(
ut_align(m_ptr, srv_page_size));
} else {
len = first_slot()->len;
m_buf = first_slot()->buf;
}
return(len);
}
/** We have to compress the individual pages and punch
holes in them on a page by page basis when writing to
tables that can be compresed at the IO level.
@param[in] len Value returned by allocate_buffer */
void copy_to_buffer(ulint len)
{
Slot* slot = first_slot();
if (len > slot->len && slot->type.is_write()) {
byte* ptr = m_buf;
ut_ad(ptr != slot->buf);
/* Copy the buffers to the combined buffer */
for (ulint i = 0; i < m_n_elems; ++i) {
slot = m_slots[i];
memmove(ptr, slot->buf, slot->len);
ptr += slot->len;
}
}
}
/** Do the I/O with ordinary, synchronous i/o functions:
@param[in] len Length of buffer for IO */
void io()
{
if (first_slot()->type.is_write()) {
for (ulint i = 0; i < m_n_elems; ++i) {
write(m_slots[i]);
}
} else {
for (ulint i = 0; i < m_n_elems; ++i) {
read(m_slots[i]);
}
}
}
/** Mark the i/os done in slots */
void done()
{
for (ulint i = 0; i < m_n_elems; ++i) {
m_slots[i]->io_already_done = true;
}
}
/** @return the first slot in the consecutive array */
Slot* first_slot()
MY_ATTRIBUTE((warn_unused_result))
{
ut_a(m_n_elems > 0);
return(m_slots[0]);
}
/** Wait for I/O requests
@param[in] global_segment The global segment
@param[in,out] event Wait on event if no active requests
@return the number of slots */
ulint check_pending(
ulint global_segment,
os_event_t event)
MY_ATTRIBUTE((warn_unused_result));
private:
/** Do the file read
@param[in,out] slot Slot that has the IO context */
void read(Slot* slot)
{
dberr_t err = os_file_read(
slot->type,
slot->file,
slot->ptr,
slot->offset,
slot->len);
ut_a(err == DB_SUCCESS);
}
/** Do the file read
@param[in,out] slot Slot that has the IO context */
void write(Slot* slot)
{
dberr_t err = os_file_write(
slot->type,
slot->name,
slot->file,
slot->ptr,
slot->offset,
slot->len);
ut_a(err == DB_SUCCESS);
}
/** @return true if the slots are adjacent and can be merged */
bool adjacent(const Slot* s1, const Slot* s2) const
{
return(s1 != s2
&& s1->file == s2->file
&& s2->offset == s1->offset + s1->len
&& s1->type == s2->type);
}
/** @return true if merge limit reached or no adjacent slots found. */
bool merge_adjacent(Slot*& current)
{
Slot* slot;
ulint offset = m_segment * m_n_slots;
slot = m_array->at(offset);
for (ulint i = 0; i < m_n_slots; ++i, ++slot) {
if (slot->is_reserved && adjacent(current, slot)) {
current = slot;
/* Found a consecutive i/o request */
m_slots[m_n_elems] = slot;
++m_n_elems;
return(m_n_elems >= m_slots.capacity());
}
}
return(true);
}
/** There were no old requests. Look for an I/O request at the lowest
offset in the array (we ignore the high 32 bits of the offset in these
heuristics) */
bool select_lowest_offset()
{
ut_ad(m_n_elems == 0);
ulint offset = m_segment * m_n_slots;
m_lowest_offset = IB_UINT64_MAX;
for (ulint i = 0; i < m_n_slots; ++i) {
Slot* slot;
slot = m_array->at(i + offset);
if (slot->is_reserved
&& slot->offset < m_lowest_offset) {
/* Found an i/o request */
m_slots[0] = slot;
m_n_elems = 1;
m_lowest_offset = slot->offset;
}
}
return(m_n_elems > 0);
}
/** Select the slot if it is older than the current oldest slot.
@param[in] slot The slot to check */
void select_if_older(Slot* slot)
{
ulint age;
age = (ulint) difftime(ut_time(), slot->reservation_time);
if ((age >= 2 && age > m_oldest)
|| (age >= 2
&& age == m_oldest
&& slot->offset < m_lowest_offset)) {
/* Found an i/o request */
m_slots[0] = slot;
m_n_elems = 1;
m_oldest = age;
m_lowest_offset = slot->offset;
}
}
/** Select th oldest slot in the array
@return true if oldest slot found */
bool select_oldest()
{
ut_ad(m_n_elems == 0);
Slot* slot;
ulint offset = m_n_slots * m_segment;
slot = m_array->at(offset);
for (ulint i = 0; i < m_n_slots; ++i, ++slot) {
if (slot->is_reserved) {
select_if_older(slot);
}
}
return(m_n_elems > 0);
}
typedef std::vector<Slot*> slots_t;
private:
ulint m_oldest;
ulint m_n_elems;
os_offset_t m_lowest_offset;
AIO* m_array;
ulint m_n_slots;
ulint m_segment;
slots_t m_slots;
byte* m_ptr;
byte* m_buf;
};
/** Wait for I/O requests
@return the number of slots */
ulint
SimulatedAIOHandler::check_pending(
ulint global_segment,
os_event_t event)
{
/* NOTE! We only access constant fields in os_aio_array.
Therefore we do not have to acquire the protecting mutex yet */
ut_ad(os_aio_validate_skip());
ut_ad(m_segment < m_array->get_n_segments());
/* Look through n slots after the segment * n'th slot */
if (AIO::is_read(m_array)
&& os_aio_recommend_sleep_for_read_threads) {
/* Give other threads chance to add several
I/Os to the array at once. */
srv_set_io_thread_op_info(
global_segment, "waiting for i/o request");
os_event_wait(event);
return(0);
}
return(m_array->slots_per_segment());
}
/** Does simulated AIO. This function should be called by an i/o-handler
thread.
@param[in] segment The number of the segment in the aio arrays to wait
for; segment 0 is the ibuf i/o thread, segment 1 the
log i/o thread, then follow the non-ibuf read threads,
and as the last are the non-ibuf write threads
@param[out] m1 the messages passed with the AIO request; note that
also in the case where the AIO operation failed, these
output parameters are valid and can be used to restart
the operation, for example
@param[out] m2 Callback argument
@param[in] type IO context
@return DB_SUCCESS or error code */
static
dberr_t
os_aio_simulated_handler(
ulint global_segment,
fil_node_t** m1,
void** m2,
IORequest* type)
{
Slot* slot;
AIO* array;
ulint segment;
os_event_t event = os_aio_segment_wait_events[global_segment];
segment = AIO::get_array_and_local_segment(&array, global_segment);
SimulatedAIOHandler handler(array, segment);
for (;;) {
srv_set_io_thread_op_info(
global_segment, "looking for i/o requests (a)");
ulint n_slots = handler.check_pending(global_segment, event);
if (n_slots == 0) {
continue;
}
handler.init(n_slots);
srv_set_io_thread_op_info(
global_segment, "looking for i/o requests (b)");
array->acquire();
ulint n_reserved;
slot = handler.check_completed(&n_reserved);
if (slot != NULL) {
break;
} else if (n_reserved == 0
&& !buf_page_cleaner_is_active
&& srv_shutdown_state == SRV_SHUTDOWN_EXIT_THREADS) {
/* There is no completed request. If there
are no pending request at all, and the system
is being shut down, exit. */
array->release();
*m1 = NULL;
*m2 = NULL;
return(DB_SUCCESS);
} else if (handler.select()) {
break;
}
/* No I/O requested at the moment */
srv_set_io_thread_op_info(
global_segment, "resetting wait event");
/* We wait here until tbere are more IO requests
for this segment. */
os_event_reset(event);
array->release();
srv_set_io_thread_op_info(
global_segment, "waiting for i/o request");
os_event_wait(event);
}
/** Found a slot that has already completed its IO */
if (slot == NULL) {
/* Merge adjacent requests */
handler.merge();
/* Check if there are several consecutive blocks
to read or write */
srv_set_io_thread_op_info(
global_segment, "consecutive i/o requests");
// Note: We don't support write combining for simulated AIO.
//ulint total_len = handler.allocate_buffer();
/* We release the array mutex for the time of the I/O: NOTE that
this assumes that there is just one i/o-handler thread serving
a single segment of slots! */
array->release();
// Note: We don't support write combining for simulated AIO.
//handler.copy_to_buffer(total_len);
srv_set_io_thread_op_info(global_segment, "doing file i/o");
handler.io();
srv_set_io_thread_op_info(global_segment, "file i/o done");
array->acquire();
handler.done();
/* We return the messages for the first slot now, and if there
were several slots, the messages will be returned with
subsequent calls of this function */
slot = handler.first_slot();
}
ut_ad(slot->is_reserved);
*m1 = slot->m1;
*m2 = slot->m2;
*type = slot->type;
array->release(slot);
array->release();
return(DB_SUCCESS);
}
/** Get the total number of pending IOs
@return the total number of pending IOs */
ulint
AIO::total_pending_io_count()
{
ulint count = s_reads->pending_io_count();
if (s_writes != NULL) {
count += s_writes->pending_io_count();
}
if (s_ibuf != NULL) {
count += s_ibuf->pending_io_count();
}
if (s_log != NULL) {
count += s_log->pending_io_count();
}
if (s_sync != NULL) {
count += s_sync->pending_io_count();
}
return(count);
}
/** Validates the consistency the aio system.
@return true if ok */
static
bool
os_aio_validate()
{
/* The methods countds and validates, we ignore the count. */
AIO::total_pending_io_count();
return(true);
}
/** Prints pending IO requests per segment of an aio array.
We probably don't need per segment statistics but they can help us
during development phase to see if the IO requests are being
distributed as expected.
@param[in,out] file File where to print
@param[in] segments Pending IO array */
void
AIO::print_segment_info(
FILE* file,
const ulint* segments)
{
ut_ad(m_n_segments > 0);
if (m_n_segments > 1) {
fprintf(file, " [");
for (ulint i = 0; i < m_n_segments; ++i, ++segments) {
if (i != 0) {
fprintf(file, ", ");
}
fprintf(file, ULINTPF, *segments);
}
fprintf(file, "] ");
}
}
/** Prints info about the aio array.
@param[in,out] file Where to print */
void
AIO::print(FILE* file)
{
ulint count = 0;
ulint n_res_seg[SRV_MAX_N_IO_THREADS];
mutex_enter(&m_mutex);
ut_a(!m_slots.empty());
ut_a(m_n_segments > 0);
memset(n_res_seg, 0x0, sizeof(n_res_seg));
for (ulint i = 0; i < m_slots.size(); ++i) {
Slot& slot = m_slots[i];
ulint segment = (i * m_n_segments) / m_slots.size();
if (slot.is_reserved) {
++count;
++n_res_seg[segment];
ut_a(slot.len > 0);
}
}
ut_a(m_n_reserved == count);
print_segment_info(file, n_res_seg);
mutex_exit(&m_mutex);
}
/** Print all the AIO segments
@param[in,out] file Where to print */
void
AIO::print_all(FILE* file)
{
s_reads->print(file);
if (s_writes != NULL) {
fputs(", aio writes:", file);
s_writes->print(file);
}
if (s_ibuf != NULL) {
fputs(",\n ibuf aio reads:", file);
s_ibuf->print(file);
}
if (s_log != NULL) {
fputs(", log i/o's:", file);
s_log->print(file);
}
if (s_sync != NULL) {
fputs(", sync i/o's:", file);
s_sync->print(file);
}
}
/** Prints info of the aio arrays.
@param[in,out] file file where to print */
void
os_aio_print(FILE* file)
{
time_t current_time;
double time_elapsed;
double avg_bytes_read;
for (ulint i = 0; i < srv_n_file_io_threads; ++i) {
fprintf(file, "I/O thread " ULINTPF " state: %s (%s)",
i,
srv_io_thread_op_info[i],
srv_io_thread_function[i]);
#ifndef _WIN32
if (!srv_use_native_aio
&& os_event_is_set(os_aio_segment_wait_events[i])) {
fprintf(file, " ev set");
}
#endif /* _WIN32 */
fprintf(file, "\n");
}
fputs("Pending normal aio reads:", file);
AIO::print_all(file);
putc('\n', file);
current_time = ut_time();
time_elapsed = 0.001 + difftime(current_time, os_last_printout);
fprintf(file,
"Pending flushes (fsync) log: " ULINTPF
"; buffer pool: " ULINTPF "\n"
ULINTPF " OS file reads, "
ULINTPF " OS file writes, "
ULINTPF " OS fsyncs\n",
fil_n_pending_log_flushes,
fil_n_pending_tablespace_flushes,
os_n_file_reads,
os_n_file_writes,
os_n_fsyncs);
const ulint n_reads = ulint(MONITOR_VALUE(MONITOR_OS_PENDING_READS));
const ulint n_writes = ulint(MONITOR_VALUE(MONITOR_OS_PENDING_WRITES));
if (n_reads != 0 || n_writes != 0) {
fprintf(file,
ULINTPF " pending reads, " ULINTPF " pending writes\n",
n_reads, n_writes);
}
if (os_n_file_reads == os_n_file_reads_old) {
avg_bytes_read = 0.0;
} else {
avg_bytes_read = (double) os_bytes_read_since_printout
/ (os_n_file_reads - os_n_file_reads_old);
}
fprintf(file,
"%.2f reads/s, " ULINTPF " avg bytes/read,"
" %.2f writes/s, %.2f fsyncs/s\n",
(os_n_file_reads - os_n_file_reads_old)
/ time_elapsed,
(ulint) avg_bytes_read,
(os_n_file_writes - os_n_file_writes_old)
/ time_elapsed,
(os_n_fsyncs - os_n_fsyncs_old)
/ time_elapsed);
os_n_file_reads_old = os_n_file_reads;
os_n_file_writes_old = os_n_file_writes;
os_n_fsyncs_old = os_n_fsyncs;
os_bytes_read_since_printout = 0;
os_last_printout = current_time;
}
/** Refreshes the statistics used to print per-second averages. */
void
os_aio_refresh_stats()
{
os_n_fsyncs_old = os_n_fsyncs;
os_bytes_read_since_printout = 0;
os_n_file_reads_old = os_n_file_reads;
os_n_file_writes_old = os_n_file_writes;
os_n_fsyncs_old = os_n_fsyncs;
os_bytes_read_since_printout = 0;
os_last_printout = ut_time();
}
/** Checks that all slots in the system have been freed, that is, there are
no pending io operations.
@return true if all free */
bool
os_aio_all_slots_free()
{
return(AIO::total_pending_io_count() == 0);
}
#ifdef UNIV_DEBUG
/** Prints all pending IO for the array
@param[in] file file where to print
@param[in] array array to process */
void
AIO::to_file(FILE* file) const
{
acquire();
fprintf(file, " " ULINTPF "\n", m_n_reserved);
for (ulint i = 0; i < m_slots.size(); ++i) {
const Slot& slot = m_slots[i];
if (slot.is_reserved) {
fprintf(file,
"%s IO for %s (offset=" UINT64PF
", size=%lu)\n",
slot.type.is_read() ? "read" : "write",
slot.name, slot.offset, (unsigned long)(slot.len));
}
}
release();
}
/** Print pending IOs for all arrays */
void
AIO::print_to_file(FILE* file)
{
fprintf(file, "Pending normal aio reads:");
s_reads->to_file(file);
if (s_writes != NULL) {
fprintf(file, "Pending normal aio writes:");
s_writes->to_file(file);
}
if (s_ibuf != NULL) {
fprintf(file, "Pending ibuf aio reads:");
s_ibuf->to_file(file);
}
if (s_log != NULL) {
fprintf(file, "Pending log i/o's:");
s_log->to_file(file);
}
if (s_sync != NULL) {
fprintf(file, "Pending sync i/o's:");
s_sync->to_file(file);
}
}
/** Prints all pending IO
@param[in] file File where to print */
void
os_aio_print_pending_io(
FILE* file)
{
AIO::print_to_file(file);
}
#endif /* UNIV_DEBUG */
/**
Set the file create umask
@param[in] umask The umask to use for file creation. */
void
os_file_set_umask(ulint umask)
{
os_innodb_umask = umask;
}
#else
#include "univ.i"
#endif /* !UNIV_INNOCHECKSUM */
/** Normalizes a directory path for the current OS:
On Windows, we convert '/' to '\', else we convert '\' to '/'.
@param[in,out] str A null-terminated directory and file path */
void
os_normalize_path(
char* str)
{
if (str != NULL) {
for (; *str; str++) {
if (*str == OS_PATH_SEPARATOR_ALT) {
*str = OS_PATH_SEPARATOR;
}
}
}
}
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