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mariadb/storage/maria/ma_blockrec.c
unknown 6bbca54d7d WL#3072 - Maria recovery 
Unit test for recovery: runs ma_test1 and ma_test2 (both only with
INSERTs and DELETEs; UPDATEs disabled as not handled by recovery)
then moves the tables elswhere; recreates tables from the log, and
compares and fails if there is a difference. Passes now.
Most of maria_read_log.c moved to ma_recovery.c, as it will be re-used
for recovery-from-ha_maria.
Bugfixes of applying of REDO_INSERT, REDO_PURGE_ROW.
Applying of REDO_PURGE_BLOCKS, REDO_DELETE_ALL, REDO_DROP_TABLE,
UNDO_ROW_INSERT (in REDO phase only, i.e. just doing records++),
UNDO_ROW_DELETE, UNDO_ROW_PURGE.
Code cleanups.
Monty: please look for "QQ". Sanja: please look for "Sanja".
Future tasks: recovery of the bitmap (easy), recovery of the state
(make it idempotent), more REDOs (Monty to work on
REDO_UPDATE?), UNDO phase...
Pushing this cset as it looks safe, contains test and bugfixes which
will help Monty implement applying of REDO_UPDATE.


sql/handler.cc:
  typo
storage/maria/Makefile.am:
  Adding ma_test_recovery (which ma_test_all invokes, and which can
  also be run alone). Most of maria_read_log.c moved to ma_recovery.c
storage/maria/ha_maria.cc:
  comments
storage/maria/ma_bitmap.c:
  fixing comments. 2 -> sizeof(maria_bitmap_marker).
  Bitmap-related part of _ma_initialize_datafile() moves in bitmap module.
  Now putting the "bm" signature when creating the first bitmap page
  (it used to happen only at next open, but that
  caused an annoying difference when testing Recovery if the original
  run didn't open the table, and it looks more
  logical like this: it goes to disk only with its signature correct);
  see the "QQ" comment towards the _ma_initialize_data_file() call
  in ma_create.c for more).
  When reading a bitmap page, verify its signature (happens when normally
  using the table or when CHECKing it; not when REPAIRing it).
storage/maria/ma_blockrec.c:
  * no need to sync the data file if table is not transactional
  * Comments, code cleanup (log-related data moved to log-related code
  block, int5store->page_store).
  * Store the table's short id into LOGREC_UNDO_ROW_PURGE, like we
  do for other records (though this record will soon be replaced
  with a CLR).
  * If "page" is 1 it means the page which extends from byte
  page*block_size+1 to (page+1)*block_size (byte number 1 being
  the first byte of the file). The last byte of the file is
  data_file_length (same convention).
  A new page needs to be created if the last byte of the page is
  beyond the last byte of the file, i.e.
   (page+1)*block_size+1 > data_file_length, so we correct the test
  (bug found when testing log applying for ma_test1 -M -T --skip-update).
  * update the page's LSN when removing a row from it during
  execution of a REDO_PURGE_ROW record (bug found when testing log
  applying for ma_test1 -M -T --skip-update).
  * applying of REDO_PURGE_BLOCKs (limited to a one-page range for now).
storage/maria/ma_blockrec.h:
  new functions. maria_bitmap_marker does not need to be exported.
storage/maria/ma_close.c:
  we can always flush the table's state when closing the last instance
  of the table. And it is needed for maria_read_log (as it does
  not use maria_lock_database()).
storage/maria/ma_control_file.c:
  when in Recovery, some assertions should not be used.
storage/maria/ma_control_file.h:
  double-inclusion safe
storage/maria/ma_create.c:
  during recovery, don't log records. Comments.
  Moving the creation of the first bitmap page to ma_bitmap.c
storage/maria/ma_delete_table.c:
  during recovery, don't log records. Log the end-zero of the dropped
  table's name, so that recovery can use the string in place without
  extending it to fit an end zero.
storage/maria/ma_loghandler.c:
  * inwrite_rec_hook also needs access to the MARIA_SHARE, like
  prewrite_rec_hook. This will be needed to update
  share->records_diff (in the upcoming patch "recovery of the state").
  * LOG_DESC::record_ends_group changed to an enum.
  * LOG_DESC for LOGREC_REDO_PURGE_BLOCKS and LOGREC_UNDO_ROW_PURGE
  corrected
  * Sanja please see the @todo LOG BUG
  * avoiding DBUG_RETURN(func()) as it gives confusing debug traces.
storage/maria/ma_loghandler.h:
  - log write hooks called while the log's lock is held (inwrite_rec_hook)
  now need the MARIA_SHARE, like prewrite_rec_hook already had
  - instead of a bool saying if this record's type ends groups or not,
  we refine: it may not end a group, it may end a group, or it may
  be a group in itself. Imagine that we had a physical write failure
  to a table before we log the UNDO, we still end up in
  external_lock(F_UNLCK) and then we log a COMMIT: we don't want
  to consider this COMMIT as ending the group of REDOs (don't want
  to execute those REDOs during Recovery), that's why we say "COMMIT
  is a group in itself, it aborts any previous group". This also
  gives one more sanity check in maria_read_log.
storage/maria/ma_recovery.c:
  New Recovery code, replacing the old pseudocode.
  Most of maria_read_log moved here.
  Call-able from ha_maria, but not enabled yet.
  Compared to the previous version of maria_read_log, some bugs have
  been fixed, debugging output can go to stdout or a disk file (for now
  it's useful for me, later it can be changed), execution of
  REDO_DROP_TABLE, REDO_DELETE_ALL, REDO_PURGE_BLOCKS has been added. Duplicate code
  has been factored into functions. We abort an unfinished group
  of records if we see a record which is a group in itself (like COMMIT).
  No need for maria_panic() after a bug (which caused tables to not
  be closed) was fixed; if there is yet another bug I prefer to see it.
  When opening a table for Recovery, set data_file_length
  and key_file_length to their real physical value (these are the
  easiest state members to restore :). Warn us if the last page
  was truncated (but Recovery handles it).
  MARIA_SHARE::state::state::records is now partly recovered (not
  idempotent, but works if recreating tables from scracth).
  When applying a REDO to a page, stamp it with the UNDO's LSN
  (current_group_end_lsn), not with the REDO's LSN; it makes
  the table more identical to the original table (easier to compare
  the two tables in the end).
  Big thing missing: some types of REDOs are not handled,
  and the UNDO phase does not exist (missing functions to execute UNDOs
  to actually rollback). So for now tests are only inserting/deleting
  a few 100 rows, closing the table and seeing if the log is applied ok;
  it works. UPDATE not handled.
storage/maria/ma_recovery.h:
  new functions: ma_recover() for recovery from inside ha_maria;
  _ma_apply_log() for maria_read_log (ma_recover() calls _ma_apply_log()).
  Btw, we need to not use the word "recover" for REPAIR/maria_chk anymore.
storage/maria/ma_rename.c:
  don't write log records during recovery
storage/maria/ma_test2.c:
  - fail if maria_info() or other subtests find some wrong information
  - new option -g to skip updates.
  - init the translog before creating the table, so that log applying
  can work.
  - in "#if 0" you'll see some fixed bugs (will be removed).
storage/maria/ma_test_all.sh:
  cleanup files. Test log applying.
storage/maria/maria_read_log.c:
  most of the logic moves to ma_recovery.c to be shared between
  maria_read_log and recovery-from-inside-mysqld.
  See ma_recovery.c for additional changes made to the moved code.
storage/maria/ma_test_recovery:
  unit test for Recovery. Tests insert and delete,
  REDO_UPDATE not yet coded.
  Script is called from ma_test_all. Can run standalone.
2007-07-26 11:56:21 +02:00

4468 lines
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/* Copyright (C) 2007 Michael Widenius
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Storage of records in block
Some clarifications about the abbrev used:
NULL fields -> Fields that may have contain a NULL value.
Not null fields -> Fields that may not contain a NULL value.
Critical fields -> Fields that can't be null and can't be dropped without
causing a table reorganization.
Maria will have a LSN at start of each page (excluding the bitmap pages)
The different page types that are in a data file are:
Bitmap pages Map of free pages in the next extent (8192 page size
gives us 256M of mapped pages / bitmap)
Head page Start of rows are stored on this page.
A rowid always points to a head page
Blob page This page is totally filled with data from one blob or by
a set of long VARCHAR/CHAR fields
Tail page This contains the last part from different rows, blobs
or varchar fields.
The data file starts with a bitmap page, followed by as many data
pages as the bitmap can cover. After this there is a new bitmap page
and more data pages etc.
For information about the bitmap page, see ma_bitmap.c
Structure of data and tail page:
The page has a row directory at end of page to allow us to do deletes
without having to reorganize the page. It also allows us to later store
some more bytes after each row to allow them to grow without having to move
around other rows.
Page header:
LSN 7 bytes Log position for last page change
PAGE_TYPE 1 byte 1 for head / 2 for tail / 3 for blob
NO 1 byte Number of row/tail entries on page
empty space 2 bytes Empty space on page
The most significant bit in PAGE_TYPE is set to 1 if the data on the page
can be compacted to get more space. (PAGE_CAN_BE_COMPACTED)
Row data
Row directory of NO entries, that consist of the following for each row
(in reverse order; i.e., first record is stored last):
Position 2 bytes Position of row on page
Length 2 bytes Length of entry
For Position and Length, the 1 most significant bit of the position and
the 1 most significant bit of the length could be used for some states of
the row (in other words, we should try to keep these reserved)
eof flag 1 byte Reserved for full page read testing. (Ie, did the
previous write get the whole block on disk.
----------------
Structure of blob pages:
LSN 7 bytes Log position for last page change
PAGE_TYPE 1 byte 3
data
-----------------
Row data structure:
Flag 1 byte Marker of which header field exists
TRANSID 6 bytes TRANSID of changing transaction
(optional, added on insert and first
update/delete)
VER_PTR 7 bytes Pointer to older version in log
(undo record)
(optional, added after first
update/delete)
DELETE_TRANSID 6 bytes (optional). TRANSID of original row.
Added on delete.
Nulls_extended 1 byte To allow us to add new DEFAULT NULL
fields (optional, added after first
change of row after alter table)
Number of ROW_EXTENT's 1-3 byte Length encoded, optional
This is the number of extents the
row is split into
First row_extent 7 byte Pointer to first row extent (optional)
Total length of length array 1-3 byte Only used if we have
char/varchar/blob fields.
Row checksum 1 byte Only if table created with checksums
Null_bits .. One bit for each NULL field (a field that may
have the value NULL)
Empty_bits .. One bit for each field that may be 'empty'.
(Both for null and not null fields).
This bit is 1 if the value for the field is
0 or empty string.
field_offsets 2 byte/offset
For each 32'th field, there is one offset
that points to where the field information
starts in the block. This is to provide
fast access to later field in the row
when we only need to return a small
set of fields.
TODO: Implement this.
Things marked above as 'optional' will only be present if the
corresponding bit is set in 'Flag' field. Flag gives us a way to
get more space on a page when doing page compaction as we don't need
to store TRANSID that have committed before the smallest running
transaction we have in memory.
Data in the following order:
(Field order is precalculated when table is created)
Critical fixed length, not null, fields. (Note, these can't be dropped)
Fixed length, null fields
Length array, 1-4 byte per field for all CHAR/VARCHAR/BLOB fields.
Number of bytes used in length array per entry is depending on max length
for field.
ROW_EXTENT's
CHAR data (space stripped)
VARCHAR data
BLOB data
Fields marked in null_bits or empty_bits are not stored in data part or
length array.
If row doesn't fit into the given block, then the first EXTENT will be
stored last on the row. This is done so that we don't break any field
data in the middle.
We first try to store the full row into one block. If that's not possible
we move out each big blob into their own extents. If this is not enough we
move out a concatenation of all varchars to their own extent.
Each blob and the concatenated char/varchar fields are stored the following
way:
- Store the parts in as many full-contiguous pages as possible.
- The last part, that doesn't fill a full page, is stored in tail page.
When doing an insert of a new row, we don't have to have
VER_PTR in the row. This will make rows that are not changed stored
efficiently. On update and delete we would add TRANSID (if it was an old
committed row) and VER_PTR to
the row. On row page compaction we can easily detect rows where
TRANSID was committed before the longest running transaction
started and we can then delete TRANSID and VER_PTR from the row to
gain more space.
If a row is deleted in Maria, we change TRANSID to the deleting
transaction's id, change VER_PTR to point to the undo record for the delete,
and add DELETE_TRANSID (the id of the transaction which last
inserted/updated the row before its deletion). DELETE_TRANSID allows an old
transaction to avoid reading the log to know if it can see the last version
before delete (in other words it reduces the probability of having to follow
VER_PTR). TODO: depending on a compilation option, evaluate the performance
impact of not storing DELETE_TRANSID (which would make the row smaller).
Description of the different parts:
Flag is coded as:
Description bit
TRANS_ID_exists 0
VER_PTR_exists 1
Row is deleted 2 (Means that DELETE_TRANSID exists)
Nulls_extended_exists 3
Row is split 7 This means that 'Number_of_row_extents' exists
Nulls_extended is the number of new DEFAULT NULL fields in the row
compared to the number of DEFAULT NULL fields when the first version
of the table was created. If Nulls_extended doesn't exist in the row,
we know it's 0 as this must be one of the original rows from when the
table was created first time. This coding allows us to add 255*8 =
2048 new fields without requiring a full alter table.
Empty_bits is used to allow us to store 0, 0.0, empty string, empty
varstring and empty blob efficiently. (This is very good for data
warehousing where NULL's are often regarded as evil). Having this
bitmap also allows us to drop information of a field during a future
delete if field was deleted with ALTER TABLE DROP COLUMN. To be able
to handle DROP COLUMN, we must store in the index header the fields
that has been dropped. When unpacking a row we will ignore dropped
fields. When storing a row, we will mark a dropped field either with a
null in the null bit map or in the empty_bits and not store any data
for it.
TODO: Add code for handling dropped fields.
A ROW EXTENT is range of pages. One ROW_EXTENT is coded as:
START_PAGE 5 bytes
PAGE_COUNT 2 bytes. High bit is used to indicate tail page/
end of blob
With 8K pages, we can cover 256M in one extent. This coding gives us a
maximum file size of 2^40*8192 = 8192 tera
As an example of ROW_EXTENT handling, assume a row with one integer
field (value 5), two big VARCHAR fields (size 250 and 8192*3), and 2
big BLOB fields that we have updated.
The record format for storing this into an empty file would be:
Page 1:
00 00 00 00 00 00 00 LSN
01 Only one row in page
xx xx Empty space on page
10 Flag: row split, VER_PTR exists
01 00 00 00 00 00 TRANSID 1
00 00 00 00 00 01 00 VER_PTR to first block in LOG file 1
5 Number of row extents
02 00 00 00 00 03 00 VARCHAR's are stored in full pages 2,3,4
0 No null fields
0 No empty fields
05 00 00 00 00 00 80 Tail page for VARCHAR, rowid 0
06 00 00 00 00 80 00 First blob, stored at page 6-133
05 00 00 00 00 01 80 Tail of first blob (896 bytes) at page 5
86 00 00 00 00 80 00 Second blob, stored at page 134-262
05 00 00 00 00 02 80 Tail of second blob (896 bytes) at page 5
05 00 5 integer
FA Length of first varchar field (size 250)
00 60 Length of second varchar field (size 8192*3)
00 60 10 First medium BLOB, 1M
01 00 10 00 Second BLOB, 1M
xx xx xx xx xx xx Varchars are stored here until end of page
..... until end of page
09 00 F4 1F 00 (Start position 9, length 8180, end byte)
*/
#define SANITY_CHECKS
#include "maria_def.h"
#include "ma_blockrec.h"
#include <lf.h>
#include "trnman.h"
/*
Struct for having a cursor over a set of extent.
This is used to loop over all extents for a row when reading
the row data. It's also used to store the tail positions for
a read row to be used by a later update/delete command.
*/
typedef struct st_maria_extent_cursor
{
/*
Pointer to packed byte array of extents for the row.
Format is described above in the header
*/
byte *extent;
/* Where data starts on page; Only for debugging */
byte *data_start;
/* Position to all tails in the row. Updated when reading a row */
MARIA_RECORD_POS *tail_positions;
/* Current page */
my_off_t page;
/* How many pages in the page region */
uint page_count;
/* Total number of extents (i.e., entries in the 'extent' slot) */
uint extent_count;
/* <> 0 if current extent is a tail page; Set while using cursor */
uint tail;
/*
<> 1 if we are working on the first extent (i.e., the one that is store in
the row header, not an extent that is stored as part of the row data).
*/
my_bool first_extent;
} MARIA_EXTENT_CURSOR;
static my_bool delete_tails(MARIA_HA *info, MARIA_RECORD_POS *tails);
static my_bool delete_head_or_tail(MARIA_HA *info,
ulonglong page, uint record_number,
my_bool head);
static void _ma_print_directory(byte *buff, uint block_size);
static void compact_page(byte *buff, uint block_size, uint rownr,
my_bool extend_block);
static uchar *store_page_range(uchar *to, MARIA_BITMAP_BLOCK *block,
uint block_size, ulong length);
static size_t fill_insert_undo_parts(MARIA_HA *info, const byte *record,
LEX_STRING *log_parts,
uint *log_parts_count);
static size_t fill_update_undo_parts(MARIA_HA *info, const byte *oldrec,
const byte *newrec,
LEX_STRING *log_parts,
uint *log_parts_count);
/****************************************************************************
Initialization
****************************************************************************/
/*
Initialize data needed for block structures
*/
/* Size of the different header elements for a row */
static uchar header_sizes[]=
{
TRANSID_SIZE,
VERPTR_SIZE,
TRANSID_SIZE, /* Delete transid */
1 /* Null extends */
};
/*
Calculate array of all used headers
Used to speed up:
size= 1;
if (flag & 1)
size+= TRANSID_SIZE;
if (flag & 2)
size+= VERPTR_SIZE;
if (flag & 4)
size+= TRANSID_SIZE
if (flag & 8)
size+= 1;
NOTES
This is called only once at startup of Maria
*/
static uchar total_header_size[1 << array_elements(header_sizes)];
#define PRECALC_HEADER_BITMASK (array_elements(total_header_size) -1)
void _ma_init_block_record_data(void)
{
uint i;
bzero(total_header_size, sizeof(total_header_size));
total_header_size[0]= FLAG_SIZE; /* Flag byte */
for (i= 1; i < array_elements(total_header_size); i++)
{
uint size= FLAG_SIZE, j, bit;
for (j= 0; (bit= (1 << j)) <= i; j++)
{
if (i & bit)
size+= header_sizes[j];
}
total_header_size[i]= size;
}
}
my_bool _ma_once_init_block_record(MARIA_SHARE *share, File data_file)
{
share->base.max_data_file_length=
(((ulonglong) 1 << ((share->base.rec_reflength-1)*8))-1) *
share->block_size;
#if SIZEOF_OFF_T == 4
set_if_smaller(share->base.max_data_file_length, INT_MAX32);
#endif
return _ma_bitmap_init(share, data_file);
}
my_bool _ma_once_end_block_record(MARIA_SHARE *share)
{
int res= _ma_bitmap_end(share);
if (share->bitmap.file.file >= 0)
{
if (flush_pagecache_blocks(share->pagecache, &share->bitmap.file,
share->temporary ? FLUSH_IGNORE_CHANGED :
FLUSH_RELEASE))
res= 1;
/*
File must be synced as it is going out of the maria_open_list and so
becoming unknown to Checkpoint.
*/
if ((share->now_transactional &&
my_sync(share->bitmap.file.file, MYF(MY_WME))) ||
my_close(share->bitmap.file.file, MYF(MY_WME)))
res= 1;
/*
Trivial assignment to guard against multiple invocations
(May happen if file are closed but we want to keep the maria object
around a bit longer)
*/
share->bitmap.file.file= -1;
}
if (share->id != 0)
translog_deassign_id_from_share(share);
return res;
}
/* Init info->cur_row structure */
my_bool _ma_init_block_record(MARIA_HA *info)
{
MARIA_ROW *row= &info->cur_row, *new_row= &info->new_row;
DBUG_ENTER("_ma_init_block_record");
if (!my_multi_malloc(MY_WME,
&row->empty_bits, info->s->base.pack_bytes,
&row->field_lengths,
info->s->base.max_field_lengths + 2,
&row->blob_lengths, sizeof(ulong) * info->s->base.blobs,
&row->null_field_lengths, (sizeof(uint) *
(info->s->base.fields -
info->s->base.blobs +
EXTRA_LENGTH_FIELDS)),
&row->tail_positions, (sizeof(MARIA_RECORD_POS) *
(info->s->base.blobs + 2)),
&new_row->empty_bits, info->s->base.pack_bytes,
&new_row->field_lengths,
info->s->base.max_field_lengths + 2,
&new_row->blob_lengths,
sizeof(ulong) * info->s->base.blobs,
&new_row->null_field_lengths, (sizeof(uint) *
(info->s->base.fields -
info->s->base.blobs +
EXTRA_LENGTH_FIELDS)),
&info->log_row_parts,
sizeof(*info->log_row_parts) *
(TRANSLOG_INTERNAL_PARTS + 2 +
info->s->base.fields + 2),
&info->update_field_data,
(info->s->base.fields * 4 +
info->s->base.max_field_lengths + 1 + 4),
NullS, 0))
DBUG_RETURN(1);
/* Skip over bytes used to store length of field length for logging */
row->field_lengths+= 2;
new_row->field_lengths+= 2;
if (my_init_dynamic_array(&info->bitmap_blocks,
sizeof(MARIA_BITMAP_BLOCK),
ELEMENTS_RESERVED_FOR_MAIN_PART, 16))
goto err;
/* The following should be big enough for all purposes */
if (my_init_dynamic_array(&info->pinned_pages,
sizeof(MARIA_PINNED_PAGE),
max(info->s->base.blobs + 2,
MARIA_MAX_TREE_LEVELS*2), 16))
goto err;
row->base_length= new_row->base_length= info->s->base_length;
/*
We need to reserve 'EXTRA_LENGTH_FIELDS' number of parts in
null_field_lengths to allow splitting of rows in 'find_where_to_split_row'
*/
row->null_field_lengths+= EXTRA_LENGTH_FIELDS;
new_row->null_field_lengths+= EXTRA_LENGTH_FIELDS;
DBUG_RETURN(0);
err:
_ma_end_block_record(info);
DBUG_RETURN(1);
}
void _ma_end_block_record(MARIA_HA *info)
{
DBUG_ENTER("_ma_end_block_record");
my_free((gptr) info->cur_row.empty_bits, MYF(MY_ALLOW_ZERO_PTR));
delete_dynamic(&info->bitmap_blocks);
delete_dynamic(&info->pinned_pages);
my_free((gptr) info->cur_row.extents, MYF(MY_ALLOW_ZERO_PTR));
/*
The data file is closed, when needed, in ma_once_end_block_record().
The following protects us from doing an extra, not allowed, close
in maria_close()
*/
info->dfile.file= -1;
DBUG_VOID_RETURN;
}
/****************************************************************************
Helper functions
****************************************************************************/
/*
Return the next used byte on the page after a directory entry.
SYNOPSIS
start_of_next_entry()
dir Directory entry to be used
RETURN
# Position in page where next entry starts.
Everything between the '*dir' and this are free to be used.
*/
static inline uint start_of_next_entry(byte *dir)
{
byte *prev;
/*
Find previous used entry. (There is always a previous entry as
the directory never starts with a deleted entry)
*/
for (prev= dir - DIR_ENTRY_SIZE ;
prev[0] == 0 && prev[1] == 0 ;
prev-= DIR_ENTRY_SIZE)
{}
return (uint) uint2korr(prev);
}
/*
Check that a region is all zero
SYNOPSIS
check_if_zero()
pos Start of memory to check
length length of memory region
NOTES
Used mainly to detect rows with wrong extent information
*/
static my_bool check_if_zero(byte *pos, uint length)
{
byte *end;
for (end= pos+ length; pos != end ; pos++)
if (pos[0] != 0)
return 1;
return 0;
}
/*
Unpin all pinned pages
SYNOPSIS
_ma_unpin_all_pages()
info Maria handler
undo_lsn LSN for undo pages. LSN_IMPOSSIBLE if we shouldn't write undo
(error)
NOTE
We unpin pages in the reverse order as they where pinned; This may not
be strictly necessary but may simplify things in the future.
info->s->rec_lsn contains the lsn for the first REDO
RETURN
0 ok
1 error (fatal disk error)
*/
void _ma_unpin_all_pages(MARIA_HA *info, LSN undo_lsn)
{
MARIA_PINNED_PAGE *page_link= ((MARIA_PINNED_PAGE*)
dynamic_array_ptr(&info->pinned_pages, 0));
MARIA_PINNED_PAGE *pinned_page= page_link + info->pinned_pages.elements;
DBUG_ENTER("_ma_unpin_all_pages");
DBUG_PRINT("info", ("undo_lsn: %lu", (ulong) undo_lsn));
/* True if not disk error */
DBUG_ASSERT((undo_lsn != LSN_IMPOSSIBLE) || !info->s->now_transactional);
if (!info->s->now_transactional)
undo_lsn= LSN_IMPOSSIBLE; /* don't try to set a LSN on pages */
while (pinned_page-- != page_link)
pagecache_unlock_by_link(info->s->pagecache, pinned_page->link,
pinned_page->unlock, PAGECACHE_UNPIN,
info->trn->rec_lsn, undo_lsn);
info->trn->rec_lsn= 0;
info->pinned_pages.elements= 0;
DBUG_VOID_RETURN;
}
/*
Find free position in directory
SYNOPSIS
find_free_position()
buff Page
block_size Size of page
res_rownr Store index to free position here
res_length Store length of found segment here
empty_space Store length of empty space on disk here. This is
all empty space, including the found block.
NOTES
If there is a free directory entry (entry with position == 0),
then use it and change it to be the size of the empty block
after the previous entry. This guarantees that all row entries
are stored on disk in inverse directory order, which makes life easier for
'compact_page()' and to know if there is free space after any block.
If there is no free entry (entry with position == 0), then we create
a new one. If there is not space for the directory entry (because
the last block overlapps with the directory), we compact the page.
We will update the offset and the length of the found dir entry to
match the position and empty space found.
buff[EMPTY_SPACE_OFFSET] is NOT updated but left up to the caller
RETURN
0 Error (directory full or last block goes over directory)
# Pointer to directory entry on page
*/
static byte *find_free_position(byte *buff, uint block_size, uint *res_rownr,
uint *res_length, uint *empty_space)
{
uint max_entry= (uint) ((uchar*) buff)[DIR_COUNT_OFFSET];
uint entry, length, first_pos;
byte *dir, *end;
DBUG_ENTER("find_free_position");
DBUG_PRINT("info", ("max_entry: %u", max_entry));
dir= (buff + block_size - DIR_ENTRY_SIZE * max_entry - PAGE_SUFFIX_SIZE);
end= buff + block_size - PAGE_SUFFIX_SIZE - DIR_ENTRY_SIZE;
*empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
/* Search after first empty position */
first_pos= PAGE_HEADER_SIZE;
for (entry= 0 ; dir <= end ; end-= DIR_ENTRY_SIZE, entry++)
{
uint tmp= uint2korr(end);
if (!tmp) /* Found not used entry */
{
length= start_of_next_entry(end) - first_pos;
int2store(end, first_pos); /* Update dir entry */
int2store(end + 2, length);
*res_rownr= entry;
*res_length= length;
DBUG_RETURN(end);
}
first_pos= tmp + uint2korr(end + 2);
}
/* No empty places in dir; create a new one */
dir= end;
/* Check if there is place for the directory entry */
if (max_entry == MAX_ROWS_PER_PAGE)
DBUG_RETURN(0);
/* Check if there is place for the directory entry */
if ((uint) (dir - buff) < first_pos)
{
/* Create place for directory */
compact_page(buff, block_size, max_entry-1, 0);
first_pos= (uint2korr(end + DIR_ENTRY_SIZE) +
uint2korr(end + DIR_ENTRY_SIZE+ 2));
*empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
}
buff[DIR_COUNT_OFFSET]= (byte) (uchar) max_entry+1;
length= (uint) (dir - buff - first_pos);
DBUG_ASSERT(length <= *empty_space - DIR_ENTRY_SIZE);
int2store(dir, first_pos);
int2store(dir+2, length); /* Current max length */
*res_rownr= max_entry;
*res_length= length;
/* Reduce directory entry size from free space size */
(*empty_space)-= DIR_ENTRY_SIZE;
DBUG_RETURN(dir);
}
/****************************************************************************
Updating records
****************************************************************************/
/*
Calculate length of all the different field parts
SYNOPSIS
calc_record_size()
info Maria handler
record Row to store
row Store statistics about row here
NOTES
The statistics is used to find out how much space a row will need
and also where we can split a row when we need to split it into several
extents.
*/
static void calc_record_size(MARIA_HA *info, const byte *record,
MARIA_ROW *row)
{
MARIA_SHARE *share= info->s;
byte *field_length_data;
MARIA_COLUMNDEF *column, *end_column;
uint *null_field_lengths= row->null_field_lengths;
ulong *blob_lengths= row->blob_lengths;
row->normal_length= row->char_length= row->varchar_length=
row->blob_length= row->extents_count= 0;
/* Create empty bitmap and calculate length of each varlength/char field */
bzero(row->empty_bits, share->base.pack_bytes);
field_length_data= row->field_lengths;
for (column= share->columndef + share->base.fixed_not_null_fields,
end_column= share->columndef + share->base.fields;
column < end_column; column++, null_field_lengths++)
{
if ((record[column->null_pos] & column->null_bit))
{
if (column->type != FIELD_BLOB)
*null_field_lengths= 0;
else
*blob_lengths++= 0;
continue;
}
switch ((enum en_fieldtype) column->type) {
case FIELD_CHECK:
case FIELD_NORMAL: /* Fixed length field */
case FIELD_ZERO:
DBUG_ASSERT(column->empty_bit == 0);
/* fall through */
case FIELD_SKIP_PRESPACE: /* Not packed */
row->normal_length+= column->length;
*null_field_lengths= column->length;
break;
case FIELD_SKIP_ZERO: /* Fixed length field */
if (memcmp(record+ column->offset, maria_zero_string,
column->length) == 0)
{
row->empty_bits[column->empty_pos] |= column->empty_bit;
*null_field_lengths= 0;
}
else
{
row->normal_length+= column->length;
*null_field_lengths= column->length;
}
break;
case FIELD_SKIP_ENDSPACE: /* CHAR */
{
const char *pos, *end;
for (pos= record + column->offset, end= pos + column->length;
end > pos && end[-1] == ' '; end--)
;
if (pos == end) /* If empty string */
{
row->empty_bits[column->empty_pos]|= column->empty_bit;
*null_field_lengths= 0;
}
else
{
uint length= (end - pos);
if (column->length <= 255)
*field_length_data++= (byte) (uchar) length;
else
{
int2store(field_length_data, length);
field_length_data+= 2;
}
row->char_length+= length;
*null_field_lengths= length;
}
break;
}
case FIELD_VARCHAR:
{
uint length, field_length_data_length;
const byte *field_pos= record + column->offset;
/* 256 is correct as this includes the length byte */
field_length_data[0]= field_pos[0];
if (column->length <= 256)
{
length= (uint) (uchar) *field_pos;
field_length_data_length= 1;
}
else
{
length= uint2korr(field_pos);
field_length_data[1]= field_pos[1];
field_length_data_length= 2;
}
*null_field_lengths= length;
if (!length)
{
row->empty_bits[column->empty_pos]|= column->empty_bit;
break;
}
row->varchar_length+= length;
*null_field_lengths= length;
field_length_data+= field_length_data_length;
break;
}
case FIELD_BLOB:
{
const byte *field_pos= record + column->offset;
uint size_length= column->length - portable_sizeof_char_ptr;
ulong blob_length= _ma_calc_blob_length(size_length, field_pos);
*blob_lengths++= blob_length;
if (!blob_length)
row->empty_bits[column->empty_pos]|= column->empty_bit;
else
{
row->blob_length+= blob_length;
memcpy(field_length_data, field_pos, size_length);
field_length_data+= size_length;
}
break;
}
default:
DBUG_ASSERT(0);
}
}
row->field_lengths_length= (uint) (field_length_data - row->field_lengths);
row->head_length= (row->base_length +
share->base.fixed_not_null_fields_length +
row->field_lengths_length +
size_to_store_key_length(row->field_lengths_length) +
row->normal_length +
row->char_length + row->varchar_length);
row->total_length= (row->head_length + row->blob_length);
if (row->total_length < share->base.min_row_length)
row->total_length= share->base.min_row_length;
}
/*
Compact page by removing all space between rows
IMPLEMENTATION
Move up all rows to start of page.
Move blocks that are directly after each other with one memmove.
TODO LATER
Remove TRANSID from rows that are visible to all transactions
SYNOPSIS
compact_page()
buff Page to compact
block_size Size of page
rownr Put empty data after this row
extend_block If 1, extend the block at 'rownr' to cover the
whole block.
*/
static void compact_page(byte *buff, uint block_size, uint rownr,
my_bool extend_block)
{
uint max_entry= (uint) ((uchar *) buff)[DIR_COUNT_OFFSET];
uint page_pos, next_free_pos, start_of_found_block, diff, end_of_found_block;
byte *dir, *end;
DBUG_ENTER("compact_page");
DBUG_PRINT("enter", ("rownr: %u", rownr));
DBUG_ASSERT(max_entry > 0 &&
max_entry < (block_size - PAGE_HEADER_SIZE -
PAGE_SUFFIX_SIZE) / DIR_ENTRY_SIZE);
/* Move all entries before and including rownr up to start of page */
dir= buff + block_size - DIR_ENTRY_SIZE * (rownr+1) - PAGE_SUFFIX_SIZE;
end= buff + block_size - DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE;
page_pos= next_free_pos= start_of_found_block= PAGE_HEADER_SIZE;
diff= 0;
for (; dir <= end ; end-= DIR_ENTRY_SIZE)
{
uint offset= uint2korr(end);
if (offset)
{
uint row_length= uint2korr(end + 2);
DBUG_ASSERT(offset >= page_pos);
DBUG_ASSERT(buff + offset + row_length <= dir);
if (offset != next_free_pos)
{
uint length= (next_free_pos - start_of_found_block);
/*
There was empty space before this and prev block
Check if we have to move previous block up to page start
*/
if (page_pos != start_of_found_block)
{
/* move up previous block */
memmove(buff + page_pos, buff + start_of_found_block, length);
}
page_pos+= length;
/* next continuous block starts here */
start_of_found_block= offset;
diff= offset - page_pos;
}
int2store(end, offset - diff); /* correct current pos */
next_free_pos= offset + row_length;
}
}
if (page_pos != start_of_found_block)
{
uint length= (next_free_pos - start_of_found_block);
memmove(buff + page_pos, buff + start_of_found_block, length);
}
start_of_found_block= uint2korr(dir);
if (rownr != max_entry - 1)
{
/* Move all entries after rownr to end of page */
uint rownr_length;
next_free_pos= end_of_found_block= page_pos=
block_size - DIR_ENTRY_SIZE * max_entry - PAGE_SUFFIX_SIZE;
diff= 0;
/* End points to entry before 'rownr' */
for (dir= buff + end_of_found_block ; dir <= end ; dir+= DIR_ENTRY_SIZE)
{
uint offset= uint2korr(dir);
uint row_length= uint2korr(dir + 2);
uint row_end= offset + row_length;
if (!offset)
continue;
DBUG_ASSERT(offset >= start_of_found_block && row_end <= next_free_pos);
if (row_end != next_free_pos)
{
uint length= (end_of_found_block - next_free_pos);
if (page_pos != end_of_found_block)
{
/* move next block down */
memmove(buff + page_pos - length, buff + next_free_pos, length);
}
page_pos-= length;
/* next continuous block starts here */
end_of_found_block= row_end;
diff= page_pos - row_end;
}
int2store(dir, offset + diff); /* correct current pos */
next_free_pos= offset;
}
if (page_pos != end_of_found_block)
{
uint length= (end_of_found_block - next_free_pos);
memmove(buff + page_pos - length, buff + next_free_pos, length);
next_free_pos= page_pos- length;
}
/* Extend rownr block to cover hole */
rownr_length= next_free_pos - start_of_found_block;
int2store(dir+2, rownr_length);
}
else
{
if (extend_block)
{
/* Extend last block cover whole page */
uint length= (uint) (dir - buff) - start_of_found_block;
int2store(dir+2, length);
}
else
{
/*
TODO:
Update (buff + EMPTY_SPACE_OFFSET) if we remove transid from rows
*/
}
buff[PAGE_TYPE_OFFSET]&= ~(byte) PAGE_CAN_BE_COMPACTED;
}
DBUG_EXECUTE("directory", _ma_print_directory(buff, block_size););
DBUG_VOID_RETURN;
}
/*
Create an empty tail or head page
SYNOPSIS
make_empty_page()
buff Page buffer
block_size Block size
page_type HEAD_PAGE or TAIL_PAGE
NOTES
EMPTY_SPACE is not updated
*/
static void make_empty_page(byte *buff, uint block_size, uint page_type)
{
bzero(buff, PAGE_HEADER_SIZE);
/*
We zero the rest of the block to avoid getting old memory information
to disk and to allow the file to be compressed better if archived.
The rest of the code does not assume the block is zeroed above
PAGE_OVERHEAD_SIZE
*/
bzero(buff+ PAGE_HEADER_SIZE, block_size - PAGE_HEADER_SIZE);
buff[PAGE_TYPE_OFFSET]= (byte) page_type;
buff[DIR_COUNT_OFFSET]= 1;
/* Store position to the first row */
int2store(buff + block_size - PAGE_SUFFIX_SIZE - DIR_ENTRY_SIZE,
PAGE_HEADER_SIZE);
}
/*
Read or initialize new head or tail page
SYNOPSIS
get_head_or_tail_page()
info Maria handler
block Block to read
buff Suggest this buffer to key cache
length Minimum space needed
page_type HEAD_PAGE || TAIL_PAGE
res Store result position here
NOTES
We don't decremented buff[EMPTY_SPACE_OFFSET] with the allocated data
as we don't know how much data the caller will actually use.
RETURN
0 ok All slots in 'res' are updated
1 error my_errno is set
*/
struct st_row_pos_info
{
byte *buff; /* page buffer */
byte *data; /* Place for data */
byte *dir; /* Directory */
uint length; /* Length for data */
uint rownr; /* Offset in directory */
uint empty_space; /* Space left on page */
};
static my_bool get_head_or_tail_page(MARIA_HA *info,
MARIA_BITMAP_BLOCK *block,
byte *buff, uint length, uint page_type,
enum pagecache_page_lock lock,
struct st_row_pos_info *res)
{
uint block_size;
MARIA_PINNED_PAGE page_link;
MARIA_SHARE *share= info->s;
DBUG_ENTER("get_head_or_tail_page");
DBUG_PRINT("enter", ("length: %u", length));
block_size= share->block_size;
if (block->org_bitmap_value == 0) /* Empty block */
{
/* New page */
make_empty_page(buff, block_size, page_type);
res->buff= buff;
res->empty_space= res->length= (block_size - PAGE_OVERHEAD_SIZE);
res->data= (buff + PAGE_HEADER_SIZE);
res->dir= res->data + res->length;
res->rownr= 0;
DBUG_ASSERT(length <= res->length);
}
else
{
byte *dir;
/* Read old page */
DBUG_ASSERT(share->pagecache->block_size == block_size);
if (!(res->buff= pagecache_read(share->pagecache,
&info->dfile,
(my_off_t) block->page, 0,
buff, share->page_type,
lock, &page_link.link)))
DBUG_RETURN(1);
page_link.unlock= PAGECACHE_LOCK_WRITE_UNLOCK;
push_dynamic(&info->pinned_pages, (void*) &page_link);
DBUG_ASSERT((res->buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) == page_type);
if (!(dir= find_free_position(res->buff, block_size, &res->rownr,
&res->length, &res->empty_space)))
goto crashed;
if (res->length < length)
{
if (res->empty_space + res->length < length)
{
compact_page(res->buff, block_size, res->rownr, 1);
/* All empty space are now after current position */
dir= (res->buff + block_size - DIR_ENTRY_SIZE * res->rownr -
PAGE_SUFFIX_SIZE);
res->length= res->empty_space= uint2korr(dir+2);
}
if (res->length < length)
goto crashed; /* Wrong bitmap information */
}
res->dir= dir;
res->data= res->buff + uint2korr(dir);
}
DBUG_RETURN(0);
crashed:
my_errno= HA_ERR_WRONG_IN_RECORD; /* File crashed */
DBUG_RETURN(1);
}
/*
Write tail for head data or blob
SYNOPSIS
write_tail()
info Maria handler
block Block to tail page
row_part Data to write to page
length Length of data
NOTES
block->page_count is updated to the directory offset for the tail
so that we can store the position in the row extent information
RETURN
0 ok
block->page_count is set to point (dir entry + TAIL_BIT)
1 error; In this case my_errno is set to the error
*/
static my_bool write_tail(MARIA_HA *info,
MARIA_BITMAP_BLOCK *block,
byte *row_part, uint length)
{
MARIA_SHARE *share= share= info->s;
MARIA_PINNED_PAGE page_link;
uint block_size= share->block_size, empty_space;
struct st_row_pos_info row_pos;
my_off_t position;
my_bool res, block_is_read;
DBUG_ENTER("write_tail");
DBUG_PRINT("enter", ("page: %lu length: %u",
(ulong) block->page, length));
info->keyread_buff_used= 1;
/* page will be pinned & locked by get_head_or_tail_page */
if (get_head_or_tail_page(info, block, info->keyread_buff, length,
TAIL_PAGE, PAGECACHE_LOCK_WRITE,
&row_pos))
DBUG_RETURN(1);
block_is_read= block->org_bitmap_value != 0;
memcpy(row_pos.data, row_part, length);
{
/* Log changes in tail block */
uchar log_data[FILEID_STORE_SIZE + PAGE_STORE_SIZE + DIRPOS_STORE_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 2];
LSN lsn;
/* Log REDO changes of tail page */
page_store(log_data+ FILEID_STORE_SIZE, block->page);
dirpos_store(log_data+ FILEID_STORE_SIZE + PAGE_STORE_SIZE,
row_pos.rownr);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
log_array[TRANSLOG_INTERNAL_PARTS + 1].str= (char*) row_pos.data;
log_array[TRANSLOG_INTERNAL_PARTS + 1].length= length;
if (translog_write_record(&lsn, LOGREC_REDO_INSERT_ROW_TAIL,
info->trn, share, sizeof(log_data) + length,
TRANSLOG_INTERNAL_PARTS + 2, log_array,
log_data))
DBUG_RETURN(1);
}
/*
Don't allocate smaller block than MIN_TAIL_SIZE (we want to give rows
some place to grow in the future)
*/
if (length < MIN_TAIL_SIZE)
length= MIN_TAIL_SIZE;
int2store(row_pos.dir + 2, length);
empty_space= row_pos.empty_space - length;
int2store(row_pos.buff + EMPTY_SPACE_OFFSET, empty_space);
block->page_count= row_pos.rownr + TAIL_BIT;
/*
If there is less directory entries free than number of possible tails
we can write for a row, we mark the page full to ensure that we don't
during _ma_bitmap_find_place() allocate more entries on the tail page
than it can hold
*/
block->empty_space= ((uint) ((uchar*) row_pos.buff)[DIR_COUNT_OFFSET] <=
MAX_ROWS_PER_PAGE - 1 - share->base.blobs ?
empty_space : 0);
block->used= BLOCKUSED_USED | BLOCKUSED_TAIL;
/* Increase data file size, if extended */
position= (my_off_t) block->page * block_size;
if (info->state->data_file_length <= position)
info->state->data_file_length= position + block_size;
DBUG_ASSERT(share->pagecache->block_size == block_size);
if (!(res= pagecache_write(share->pagecache,
&info->dfile, block->page, 0,
row_pos.buff,share->page_type,
block_is_read ? PAGECACHE_LOCK_WRITE_TO_READ :
PAGECACHE_LOCK_READ,
block_is_read ? PAGECACHE_PIN_LEFT_PINNED :
PAGECACHE_PIN,
PAGECACHE_WRITE_DELAY, &page_link.link)))
{
page_link.unlock= PAGECACHE_LOCK_READ_UNLOCK;
if (block_is_read)
{
/* Change the lock used when we read the page */
set_dynamic(&info->pinned_pages, (void*) &page_link,
info->pinned_pages.elements-1);
}
else
push_dynamic(&info->pinned_pages, (void*) &page_link);
}
DBUG_RETURN(res);
}
/*
Write full pages
SYNOPSIS
write_full_pages()
info Maria handler
lsn LSN for the undo record
block Where to write data
data Data to write
length Length of data
NOTES
Logging of the changes to the full pages are done in the caller
write_block_record().
RETURN
0 ok
1 error on write
*/
static my_bool write_full_pages(MARIA_HA *info,
LSN lsn,
MARIA_BITMAP_BLOCK *block,
byte *data, ulong length)
{
my_off_t page;
MARIA_SHARE *share= share= info->s;
uint block_size= share->block_size;
uint data_size= FULL_PAGE_SIZE(block_size);
byte *buff= info->keyread_buff;
uint page_count;
my_off_t position;
DBUG_ENTER("write_full_pages");
DBUG_PRINT("enter", ("length: %lu page: %lu page_count: %lu",
(ulong) length, (ulong) block->page,
(ulong) block->page_count));
info->keyread_buff_used= 1;
page= block->page;
page_count= block->page_count;
position= (my_off_t) (page + page_count) * block_size;
if (info->state->data_file_length < position)
info->state->data_file_length= position;
/* Increase data file size, if extended */
for (; length; data+= data_size)
{
uint copy_length;
if (!page_count--)
{
block++;
page= block->page;
page_count= block->page_count - 1;
DBUG_PRINT("info", ("page: %lu page_count: %lu",
(ulong) block->page, (ulong) block->page_count));
position= (page + page_count + 1) * block_size;
if (info->state->data_file_length < position)
info->state->data_file_length= position;
}
lsn_store(buff, lsn);
buff[PAGE_TYPE_OFFSET]= (byte) BLOB_PAGE;
copy_length= min(data_size, length);
memcpy(buff + LSN_SIZE + PAGE_TYPE_SIZE, data, copy_length);
length-= copy_length;
DBUG_ASSERT(share->pagecache->block_size == block_size);
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, share->page_type,
PAGECACHE_LOCK_LEFT_UNLOCKED,
PAGECACHE_PIN_LEFT_UNPINNED,
PAGECACHE_WRITE_DELAY,
0))
DBUG_RETURN(1);
page++;
block->used= BLOCKUSED_USED;
}
DBUG_RETURN(0);
}
/*
Store ranges of full pages in compact format for logging
SYNOPSIS
store_page_range()
to Store data here
block Where pages are to be written
block_size block size
length Length of data to be written
Normally this is full pages, except for the last
tail block that may only partly fit the last page.
RETURN
# end position for 'to'
*/
static uchar *store_page_range(uchar *to, MARIA_BITMAP_BLOCK *block,
uint block_size, ulong length)
{
uint data_size= FULL_PAGE_SIZE(block_size);
ulong pages_left= (length + data_size -1) / data_size;
uint page_count;
DBUG_ENTER("store_page_range");
do
{
ulonglong page;
page= block->page;
page_count= block->page_count;
block++;
if (page_count > pages_left)
page_count= pages_left;
page_store(to, page);
to+= PAGE_STORE_SIZE;
pagerange_store(to, page_count);
to+= PAGERANGE_STORE_SIZE;
} while ((pages_left-= page_count));
DBUG_RETURN(to);
}
/*
Store packed extent data
SYNOPSIS
store_extent_info()
to Store first packed data here
row_extents_second_part Store rest here
first_block First block to store
count Number of blocks
NOTES
We don't have to store the position for the head block
*/
static void store_extent_info(byte *to,
byte *row_extents_second_part,
MARIA_BITMAP_BLOCK *first_block,
uint count)
{
MARIA_BITMAP_BLOCK *block, *end_block;
uint copy_length;
my_bool first_found= 0;
for (block= first_block, end_block= first_block+count ;
block < end_block; block++)
{
/* The following is only false for marker blocks */
if (likely(block->used & BLOCKUSED_USED))
{
DBUG_ASSERT(block->page_count != 0);
page_store(to, block->page);
pagerange_store(to + PAGE_STORE_SIZE, block->page_count);
to+= ROW_EXTENT_SIZE;
if (!first_found)
{
first_found= 1;
to= row_extents_second_part;
}
}
}
copy_length= (count - 1) * ROW_EXTENT_SIZE;
/*
In some unlikely cases we have allocated to many blocks. Clear this
data.
*/
bzero(to, (my_size_t) (row_extents_second_part + copy_length - to));
}
/*
Free regions of pages with logging
RETURN
0 ok
1 error
*/
static my_bool free_full_pages(MARIA_HA *info, MARIA_ROW *row)
{
uchar log_data[FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 2];
LSN lsn;
size_t extents_length= row->extents_count * ROW_EXTENT_SIZE;
DBUG_ENTER("free_full_pages");
pagerange_store(log_data + FILEID_STORE_SIZE,
row->extents_count);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
log_array[TRANSLOG_INTERNAL_PARTS + 1].str= row->extents;
log_array[TRANSLOG_INTERNAL_PARTS + 1].length= extents_length;
if (translog_write_record(&lsn, LOGREC_REDO_PURGE_BLOCKS, info->trn,
info->s, sizeof(log_data) + extents_length,
TRANSLOG_INTERNAL_PARTS + 2, log_array,
log_data))
DBUG_RETURN(1);
DBUG_RETURN (_ma_bitmap_free_full_pages(info, row->extents,
row->extents_count));
}
/*
Free one page range
NOTES
This is very similar to free_full_pages()
RETURN
0 ok
1 error
*/
static my_bool free_full_page_range(MARIA_HA *info, ulonglong page, uint count)
{
my_bool res= 0;
if (pagecache_delete_pages(info->s->pagecache, &info->dfile,
page, count, PAGECACHE_LOCK_WRITE, 0))
res= 1;
if (info->s->now_transactional)
{
LSN lsn;
/** @todo unify log_data's shape with delete_head_or_tail() */
uchar log_data[FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE +
ROW_EXTENT_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 1];
DBUG_ASSERT(info->trn->rec_lsn);
pagerange_store(log_data + FILEID_STORE_SIZE, 1);
page_store(log_data + FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE,
page);
int2store(log_data + FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE +
PAGE_STORE_SIZE, count);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
if (translog_write_record(&lsn, LOGREC_REDO_PURGE_BLOCKS,
info->trn, info->s, sizeof(log_data),
TRANSLOG_INTERNAL_PARTS + 1, log_array,
log_data))
res= 1;
}
pthread_mutex_lock(&info->s->bitmap.bitmap_lock);
if (_ma_reset_full_page_bits(info, &info->s->bitmap, page,
count))
res= 1;
pthread_mutex_unlock(&info->s->bitmap.bitmap_lock);
return res;
}
/**
@brief Write a record to a (set of) pages
@param info Maria handler
@param old_record Original record in case of update; NULL in case of
insert
@param record Record we should write
@param row Statistics about record (calculated by
calc_record_size())
@param map_blocks On which pages the record should be stored
@param row_pos Position on head page where to put head part of
record
@note
On return all pinned pages are released.
@return Operation status
@retval 0 OK
@retval 1 Error
*/
static my_bool write_block_record(MARIA_HA *info,
const byte *old_record, const byte *record,
MARIA_ROW *row,
MARIA_BITMAP_BLOCKS *bitmap_blocks,
my_bool head_block_is_read,
struct st_row_pos_info *row_pos)
{
byte *data, *end_of_data, *tmp_data_used, *tmp_data;
byte *row_extents_first_part, *row_extents_second_part;
byte *field_length_data;
byte *page_buff;
MARIA_BITMAP_BLOCK *block, *head_block;
MARIA_SHARE *share= info->s;
MARIA_COLUMNDEF *column, *end_column;
MARIA_PINNED_PAGE page_link;
uint block_size, flag;
ulong *blob_lengths;
my_bool row_extents_in_use, blob_full_pages_exists;
LSN lsn;
my_off_t position;
DBUG_ENTER("write_block_record");
LINT_INIT(row_extents_first_part);
LINT_INIT(row_extents_second_part);
head_block= bitmap_blocks->block;
block_size= share->block_size;
page_buff= row_pos->buff;
/* Position on head page where we should store the head part */
data= row_pos->data;
end_of_data= data + row_pos->length;
/* Write header */
flag= share->base.default_row_flag;
row_extents_in_use= 0;
if (unlikely(row->total_length > row_pos->length))
{
/* Need extent */
if (bitmap_blocks->count <= 1)
goto crashed; /* Wrong in bitmap */
flag|= ROW_FLAG_EXTENTS;
row_extents_in_use= 1;
}
/* For now we have only a minimum header */
*data++= (uchar) flag;
if (unlikely(flag & ROW_FLAG_NULLS_EXTENDED))
*data++= (uchar) (share->base.null_bytes -
share->base.original_null_bytes);
if (row_extents_in_use)
{
/* Store first extent in header */
store_key_length_inc(data, bitmap_blocks->count - 1);
row_extents_first_part= data;
data+= ROW_EXTENT_SIZE;
}
if (share->base.pack_fields)
store_key_length_inc(data, row->field_lengths_length);
if (share->calc_checksum)
*(data++)= (byte) info->cur_row.checksum;
memcpy(data, record, share->base.null_bytes);
data+= share->base.null_bytes;
memcpy(data, row->empty_bits, share->base.pack_bytes);
data+= share->base.pack_bytes;
/*
Allocate a buffer of rest of data (except blobs)
To avoid double copying of data, we copy as many columns that fits into
the page. The rest goes into info->packed_row.
Using an extra buffer, instead of doing continuous writes to different
pages, uses less code and we don't need to have to do a complex call
for every data segment we want to store.
*/
if (_ma_alloc_buffer(&info->rec_buff, &info->rec_buff_size,
row->head_length))
DBUG_RETURN(1);
tmp_data_used= 0; /* Either 0 or last used byte in 'data' */
tmp_data= data;
if (row_extents_in_use)
{
uint copy_length= (bitmap_blocks->count - 2) * ROW_EXTENT_SIZE;
if (!tmp_data_used && tmp_data + copy_length > end_of_data)
{
tmp_data_used= tmp_data;
tmp_data= info->rec_buff;
}
row_extents_second_part= tmp_data;
/*
We will copy the extents here when we have figured out the tail
positions.
*/
tmp_data+= copy_length;
}
/* Copy fields that has fixed lengths (primary key etc) */
for (column= share->columndef,
end_column= column + share->base.fixed_not_null_fields;
column < end_column; column++)
{
if (!tmp_data_used && tmp_data + column->length > end_of_data)
{
tmp_data_used= tmp_data;
tmp_data= info->rec_buff;
}
memcpy(tmp_data, record + column->offset, column->length);
tmp_data+= column->length;
}
/* Copy length of data for variable length fields */
if (!tmp_data_used && tmp_data + row->field_lengths_length > end_of_data)
{
tmp_data_used= tmp_data;
tmp_data= info->rec_buff;
}
field_length_data= row->field_lengths;
memcpy(tmp_data, field_length_data, row->field_lengths_length);
tmp_data+= row->field_lengths_length;
/* Copy variable length fields and fields with null/zero */
for (end_column= share->columndef + share->base.fields - share->base.blobs;
column < end_column ;
column++)
{
const byte *field_pos;
ulong length;
if ((record[column->null_pos] & column->null_bit) ||
(row->empty_bits[column->empty_pos] & column->empty_bit))
continue;
field_pos= record + column->offset;
switch ((enum en_fieldtype) column->type) {
case FIELD_NORMAL: /* Fixed length field */
case FIELD_SKIP_PRESPACE:
case FIELD_SKIP_ZERO: /* Fixed length field */
length= column->length;
break;
case FIELD_SKIP_ENDSPACE: /* CHAR */
/* Char that is space filled */
if (column->length <= 255)
length= (uint) (uchar) *field_length_data++;
else
{
length= uint2korr(field_length_data);
field_length_data+= 2;
}
break;
case FIELD_VARCHAR:
if (column->length <= 256)
{
length= (uint) (uchar) *field_length_data++;
field_pos++; /* Skip length byte */
}
else
{
length= uint2korr(field_length_data);
field_length_data+= 2;
field_pos+= 2;
}
break;
default: /* Wrong data */
DBUG_ASSERT(0);
break;
}
if (!tmp_data_used && tmp_data + length > end_of_data)
{
/* Data didn't fit in page; Change to use tmp buffer */
tmp_data_used= tmp_data;
tmp_data= info->rec_buff;
}
memcpy((char*) tmp_data, (char*) field_pos, length);
tmp_data+= length;
}
block= head_block + head_block->sub_blocks; /* Point to first blob data */
end_column= column + share->base.blobs;
blob_lengths= row->blob_lengths;
if (!tmp_data_used)
{
/* Still room on page; Copy as many blobs we can into this page */
data= tmp_data;
for (; column < end_column && *blob_lengths < (ulong) (end_of_data - data);
column++, blob_lengths++)
{
byte *tmp_pos;
uint length;
if (!*blob_lengths) /* Null or "" */
continue;
length= column->length - portable_sizeof_char_ptr;
memcpy_fixed((byte*) &tmp_pos, record + column->offset + length,
sizeof(char*));
memcpy(data, tmp_pos, *blob_lengths);
data+= *blob_lengths;
/* Skip over tail page that was to be used to store blob */
block++;
bitmap_blocks->tail_page_skipped= 1;
}
if (head_block->sub_blocks > 1)
{
/* We have allocated pages that where not used */
bitmap_blocks->page_skipped= 1;
}
}
else
data= tmp_data_used; /* Get last used on page */
{
/* Update page directory */
uint length= (uint) (data - row_pos->data);
DBUG_PRINT("info", ("head length: %u", length));
if (length < info->s->base.min_row_length)
{
uint diff_length= info->s->base.min_row_length - length;
bzero(data, diff_length);
data+= diff_length;
length= info->s->base.min_row_length;
}
int2store(row_pos->dir + 2, length);
/* update empty space at start of block */
row_pos->empty_space-= length;
int2store(page_buff + EMPTY_SPACE_OFFSET, row_pos->empty_space);
/* Mark in bitmaps how the current page was actually used */
head_block->empty_space= row_pos->empty_space;
if (page_buff[DIR_COUNT_OFFSET] == (char) MAX_ROWS_PER_PAGE)
head_block->empty_space= 0; /* Page is full */
head_block->used= BLOCKUSED_USED;
}
/*
Now we have to write tail pages, as we need to store the position
to them in the row extent header.
We first write out all blob tails, to be able to store them in
the current page or 'tmp_data'.
Then we write the tail of the non-blob fields (The position to the
tail page is stored either in row header, the extents in the head
page or in the first full page of the non-blob data. It's never in
the tail page of the non-blob data)
*/
blob_full_pages_exists= 0;
if (row_extents_in_use)
{
if (column != end_column) /* If blob fields */
{
MARIA_COLUMNDEF *save_column= column;
MARIA_BITMAP_BLOCK *save_block= block;
MARIA_BITMAP_BLOCK *end_block;
ulong *save_blob_lengths= blob_lengths;
for (; column < end_column; column++, blob_lengths++)
{
byte *blob_pos;
if (!*blob_lengths) /* Null or "" */
continue;
if (block[block->sub_blocks - 1].used & BLOCKUSED_TAIL)
{
uint length;
length= column->length - portable_sizeof_char_ptr;
memcpy_fixed((byte *) &blob_pos, record + column->offset + length,
sizeof(char*));
length= *blob_lengths % FULL_PAGE_SIZE(block_size); /* tail size */
if (length != *blob_lengths)
blob_full_pages_exists= 1;
if (write_tail(info, block + block->sub_blocks-1,
blob_pos + *blob_lengths - length,
length))
goto disk_err;
}
else
blob_full_pages_exists= 1;
for (end_block= block + block->sub_blocks; block < end_block; block++)
{
/*
Set only a bit, to not cause bitmap code to believe a block is full
when there is still a lot of entries in it
*/
block->used|= BLOCKUSED_USED;
}
}
column= save_column;
block= save_block;
blob_lengths= save_blob_lengths;
}
if (tmp_data_used) /* non blob data overflows */
{
MARIA_BITMAP_BLOCK *cur_block, *end_block, *last_head_block;
MARIA_BITMAP_BLOCK *head_tail_block= 0;
ulong length;
ulong data_length= (tmp_data - info->rec_buff);
#ifdef MONTY_WILL_KNOW
#ifdef SANITY_CHECKS
if (cur_block->sub_blocks == 1)
goto crashed; /* no reserved full or tails */
#endif
#endif
/*
Find out where to write tail for non-blob fields.
Problem here is that the bitmap code may have allocated more
space than we need. We have to handle the following cases:
- Bitmap code allocated a tail page we don't need.
- The last full page allocated needs to be changed to a tail page
(Because we where able to put more data on the head page than
the bitmap allocation assumed)
The reserved pages in bitmap_blocks for the main page has one of
the following allocations:
- Full pages, with following blocks:
# * full pages
empty page ; To be used if we change last full to tail page. This
has 'count' = 0.
tail page (optional, if last full page was part full)
- One tail page
*/
cur_block= head_block + 1;
end_block= head_block + head_block->sub_blocks;
/*
Loop until we have find a block bigger than we need or
we find the empty page block.
*/
while (data_length >= (length= (cur_block->page_count *
FULL_PAGE_SIZE(block_size))) &&
cur_block->page_count)
{
#ifdef SANITY_CHECKS
if ((cur_block == end_block) || (cur_block->used & BLOCKUSED_USED))
goto crashed;
#endif
data_length-= length;
(cur_block++)->used= BLOCKUSED_USED;
}
last_head_block= cur_block;
if (data_length)
{
if (cur_block->page_count == 0)
{
/* Skip empty filler block */
cur_block++;
}
#ifdef SANITY_CHECKS
if ((cur_block >= end_block))
goto crashed;
#endif
if (cur_block->used & BLOCKUSED_TAIL)
{
DBUG_ASSERT(data_length < MAX_TAIL_SIZE(block_size));
/* tail written to full tail page */
cur_block->used= BLOCKUSED_USED;
head_tail_block= cur_block;
}
else if (data_length > length - MAX_TAIL_SIZE(block_size))
{
/* tail written to full page */
cur_block->used= BLOCKUSED_USED;
if ((cur_block != end_block - 1) &&
(end_block[-1].used & BLOCKUSED_TAIL))
bitmap_blocks->tail_page_skipped= 1;
}
else
{
/*
cur_block is a full block, followed by an empty and optional
tail block. Change cur_block to a tail block or split it
into full blocks and tail blocks.
TODO:
If there is enough space on the following tail block, use
this instead of creating a new tail block.
*/
DBUG_ASSERT(cur_block[1].page_count == 0);
if (cur_block->page_count == 1)
{
/* convert full block to tail block */
cur_block->used= BLOCKUSED_USED | BLOCKUSED_TAIL;
head_tail_block= cur_block;
}
else
{
DBUG_ASSERT(data_length < length - FULL_PAGE_SIZE(block_size));
DBUG_PRINT("info", ("Splitting blocks into full and tail"));
cur_block[1].page= (cur_block->page + cur_block->page_count - 1);
cur_block[1].page_count= 1; /* Avoid DBUG_ASSERT */
cur_block[1].used= BLOCKUSED_USED | BLOCKUSED_TAIL;
cur_block->page_count--;
cur_block->used= BLOCKUSED_USED;
last_head_block= head_tail_block= cur_block+1;
}
if (end_block[-1].used & BLOCKUSED_TAIL)
bitmap_blocks->tail_page_skipped= 1;
}
}
else
{
/* Must be an empty or tail page */
DBUG_ASSERT(cur_block->page_count == 0 ||
cur_block->used & BLOCKUSED_TAIL);
if (end_block[-1].used & BLOCKUSED_TAIL)
bitmap_blocks->tail_page_skipped= 1;
}
/*
Write all extents into page or tmp_data
Note that we still don't have a correct position for the tail
of the non-blob fields.
*/
store_extent_info(row_extents_first_part,
row_extents_second_part,
head_block+1, bitmap_blocks->count - 1);
if (head_tail_block)
{
ulong data_length= (tmp_data - info->rec_buff);
uint length;
byte *extent_data;
length= (uint) (data_length % FULL_PAGE_SIZE(block_size));
if (write_tail(info, head_tail_block,
info->rec_buff + data_length - length,
length))
goto disk_err;
tmp_data-= length; /* Remove the tail */
/* Store the tail position for the non-blob fields */
if (head_tail_block == head_block + 1)
{
/*
We had a head block + tail block, which means that the
tail block is the first extent
*/
extent_data= row_extents_first_part;
}
else
{
/*
We have a head block + some full blocks + tail block
last_head_block is pointing after the last used extent
for the head block.
*/
extent_data= row_extents_second_part +
((last_head_block - head_block) - 2) * ROW_EXTENT_SIZE;
}
DBUG_ASSERT(uint2korr(extent_data+5) & TAIL_BIT);
page_store(extent_data, head_tail_block->page);
int2store(extent_data + PAGE_STORE_SIZE, head_tail_block->page_count);
}
}
else
store_extent_info(row_extents_first_part,
row_extents_second_part,
head_block+1, bitmap_blocks->count - 1);
}
if (share->now_transactional)
{
uchar log_data[FILEID_STORE_SIZE + PAGE_STORE_SIZE + DIRPOS_STORE_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 2];
size_t data_length= (size_t) (data - row_pos->data);
/* Log REDO changes of head page */
page_store(log_data + FILEID_STORE_SIZE, head_block->page);
dirpos_store(log_data + FILEID_STORE_SIZE + PAGE_STORE_SIZE,
row_pos->rownr);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
log_array[TRANSLOG_INTERNAL_PARTS + 1].str= (char*) row_pos->data;
log_array[TRANSLOG_INTERNAL_PARTS + 1].length= data_length;
if (translog_write_record(&lsn, LOGREC_REDO_INSERT_ROW_HEAD, info->trn,
share, sizeof(log_data) + data_length,
TRANSLOG_INTERNAL_PARTS + 2, log_array,
log_data))
goto disk_err;
}
/* Increase data file size, if extended */
position= (my_off_t) head_block->page * block_size;
if (info->state->data_file_length <= position)
info->state->data_file_length= position + block_size;
DBUG_ASSERT(share->pagecache->block_size == block_size);
if (pagecache_write(share->pagecache,
&info->dfile, head_block->page, 0,
page_buff, share->page_type,
head_block_is_read ? PAGECACHE_LOCK_WRITE_TO_READ :
PAGECACHE_LOCK_READ,
head_block_is_read ? PAGECACHE_PIN_LEFT_PINNED :
PAGECACHE_PIN,
PAGECACHE_WRITE_DELAY, &page_link.link))
goto disk_err;
page_link.unlock= PAGECACHE_LOCK_READ_UNLOCK;
if (head_block_is_read)
{
/* Head page is always the first pinned page */
set_dynamic(&info->pinned_pages, (void*) &page_link, 0);
}
else
push_dynamic(&info->pinned_pages, (void*) &page_link);
if (share->now_transactional && (tmp_data_used || blob_full_pages_exists))
{
/*
Log REDO writes for all full pages (head part and all blobs)
We write all here to be able to generate the UNDO record early
so that we can write the LSN for the UNDO record to all full pages.
*/
uchar tmp_log_data[FILEID_STORE_SIZE + LSN_STORE_SIZE + PAGE_STORE_SIZE +
ROW_EXTENT_SIZE * ROW_EXTENTS_ON_STACK];
uchar *log_data, *log_pos;
LEX_STRING tmp_log_array[TRANSLOG_INTERNAL_PARTS + 2 +
ROW_EXTENTS_ON_STACK];
LEX_STRING *log_array_pos, *log_array;
int error;
ulong log_entry_length= 0;
/* If few extents, then allocate things on stack to avoid a malloc call */
if (bitmap_blocks->count < ROW_EXTENTS_ON_STACK)
{
log_array= tmp_log_array;
log_data= tmp_log_data;
}
else
{
if (my_multi_malloc(MY_WME, &log_array,
(uint) ((bitmap_blocks->count +
TRANSLOG_INTERNAL_PARTS + 2) *
sizeof(*log_array)),
&log_data, bitmap_blocks->count * ROW_EXTENT_SIZE,
NullS))
goto disk_err;
}
log_pos= log_data + FILEID_STORE_SIZE;
log_array_pos= log_array+ TRANSLOG_INTERNAL_PARTS+1;
if (tmp_data_used)
{
/* Full head pages */
size_t data_length= (ulong) (tmp_data - info->rec_buff);
log_pos= store_page_range(log_pos, head_block+1, block_size,
data_length);
log_array_pos->str= (char*) info->rec_buff;
log_array_pos->length= data_length;
log_entry_length+= data_length;
log_array_pos++;
}
if (blob_full_pages_exists)
{
MARIA_COLUMNDEF *tmp_column= column;
ulong *tmp_blob_lengths= blob_lengths;
MARIA_BITMAP_BLOCK *tmp_block= block;
/* Full blob pages */
for (; tmp_column < end_column; tmp_column++, tmp_blob_lengths++)
{
ulong blob_length;
uint length;
if (!*tmp_blob_lengths) /* Null or "" */
continue;
length= tmp_column->length - portable_sizeof_char_ptr;
blob_length= *tmp_blob_lengths;
if (tmp_block[tmp_block->sub_blocks - 1].used & BLOCKUSED_TAIL)
blob_length-= (blob_length % FULL_PAGE_SIZE(block_size));
if (blob_length)
{
memcpy_fixed((byte*) &log_array_pos->str,
record + column->offset + length,
sizeof(byte*));
log_array_pos->length= blob_length;
log_entry_length+= blob_length;
log_array_pos++;
log_pos= store_page_range(log_pos, tmp_block, block_size,
blob_length);
tmp_block+= tmp_block->sub_blocks;
}
}
}
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= (size_t) (log_pos -
log_data);
log_entry_length+= (log_pos - log_data);
/* trn->rec_lsn is already set earlier in this function */
error= translog_write_record(&lsn, LOGREC_REDO_INSERT_ROW_BLOBS,
info->trn, share, log_entry_length,
(uint) (log_array_pos - log_array),
log_array, log_data);
if (log_array != tmp_log_array)
my_free((gptr) log_array, MYF(0));
if (error)
goto disk_err;
}
/* Write UNDO record */
if (share->now_transactional)
{
uchar log_data[LSN_STORE_SIZE + FILEID_STORE_SIZE +
PAGE_STORE_SIZE + DIRPOS_STORE_SIZE];
LEX_STRING *log_array= info->log_row_parts;
/* LOGREC_UNDO_ROW_INSERT & LOGREC_UNDO_ROW_INSERT share same header */
lsn_store(log_data, info->trn->undo_lsn);
page_store(log_data+ LSN_STORE_SIZE + FILEID_STORE_SIZE,
head_block->page);
dirpos_store(log_data+ LSN_STORE_SIZE + FILEID_STORE_SIZE +
PAGE_STORE_SIZE,
row_pos->rownr);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
if (!old_record)
{
/* Write UNDO log record for the INSERT */
if (translog_write_record(&lsn, LOGREC_UNDO_ROW_INSERT,
info->trn, share, sizeof(log_data),
TRANSLOG_INTERNAL_PARTS + 1, log_array,
log_data + LSN_STORE_SIZE))
goto disk_err;
}
else
{
/* Write UNDO log record for the UPDATE */
size_t row_length;
uint row_parts_count;
row_length= fill_update_undo_parts(info, old_record, record,
info->log_row_parts +
TRANSLOG_INTERNAL_PARTS + 1,
&row_parts_count);
if (translog_write_record(&lsn, LOGREC_UNDO_ROW_UPDATE, info->trn,
share, sizeof(log_data) + row_length,
TRANSLOG_INTERNAL_PARTS + 1 + row_parts_count,
log_array, log_data + LSN_STORE_SIZE))
goto disk_err;
}
}
_ma_unpin_all_pages(info, info->trn->undo_lsn);
if (tmp_data_used)
{
/*
Write data stored in info->rec_buff to pages
This is the char/varchar data that didn't fit into the head page.
*/
DBUG_ASSERT(bitmap_blocks->count != 0);
if (write_full_pages(info, info->trn->undo_lsn, head_block + 1,
info->rec_buff, (ulong) (tmp_data - info->rec_buff)))
goto disk_err;
}
/* Write rest of blobs (data, but no tails as they are already written) */
for (; column < end_column; column++, blob_lengths++)
{
byte *blob_pos;
uint length;
ulong blob_length;
if (!*blob_lengths) /* Null or "" */
continue;
length= column->length - portable_sizeof_char_ptr;
memcpy_fixed((byte*) &blob_pos, record + column->offset + length,
sizeof(char*));
/* remove tail part */
blob_length= *blob_lengths;
if (block[block->sub_blocks - 1].used & BLOCKUSED_TAIL)
blob_length-= (blob_length % FULL_PAGE_SIZE(block_size));
if (write_full_pages(info, info->trn->undo_lsn, block,
blob_pos, blob_length))
goto disk_err;
block+= block->sub_blocks;
}
/* Release not used space in used pages */
if (_ma_bitmap_release_unused(info, bitmap_blocks))
goto disk_err;
DBUG_RETURN(0);
crashed:
/* Something was wrong with data on page */
my_errno= HA_ERR_WRONG_IN_RECORD;
disk_err:
/**
@todo RECOVERY we are going to let dirty pages go to disk while we have
logged UNDO, this violates WAL. We must mark the table corrupted!
@todo RECOVERY we have written some REDOs without a closing UNDO,
it's possible that a next operation by this transaction succeeds and then
Recovery would glue the "orphan REDOs" to the succeeded operation and
execute the failed REDOs. We need some mark "abort this group" in the
log, or mark the table corrupted (then user will repair it and thus REDOs
will be skipped).
@todo RECOVERY to not let write errors go unnoticed, pagecache_write()
should take a MARIA_HA* in argument, and it it
fails when flushing a page to disk it should call
(*the_maria_ha->write_error_func)(the_maria_ha)
and this hook will mark the table corrupted.
Maybe hook should be stored in the pagecache's block structure, or in a
hash "file->maria_ha*".
@todo RECOVERY we should distinguish below between log write error and
table write error. The former should stop Maria immediately, the latter
should mark the table corrupted.
*/
/* Unpin all pinned pages to not cause problems for disk cache */
_ma_unpin_all_pages(info, 0);
DBUG_RETURN(1);
}
/*
Write a record (to get the row id for it)
SYNOPSIS
_ma_write_init_block_record()
info Maria handler
record Record to write
NOTES
This is done BEFORE we write the keys to the row!
RETURN
HA_OFFSET_ERROR Something went wrong
# Rowid for row
*/
MARIA_RECORD_POS _ma_write_init_block_record(MARIA_HA *info,
const byte *record)
{
MARIA_BITMAP_BLOCKS *blocks= &info->cur_row.insert_blocks;
struct st_row_pos_info row_pos;
DBUG_ENTER("_ma_write_init_block_record");
calc_record_size(info, record, &info->cur_row);
if (_ma_bitmap_find_place(info, &info->cur_row, blocks))
DBUG_RETURN(HA_OFFSET_ERROR); /* Error reading bitmap */
/* page will be pinned & locked by get_head_or_tail_page */
if (get_head_or_tail_page(info, blocks->block, info->buff,
info->s->base.min_row_length, HEAD_PAGE,
PAGECACHE_LOCK_WRITE, &row_pos))
DBUG_RETURN(HA_OFFSET_ERROR);
info->cur_row.lastpos= ma_recordpos(blocks->block->page, row_pos.rownr);
if (info->s->calc_checksum)
info->cur_row.checksum= (info->s->calc_checksum)(info,record);
if (write_block_record(info, (byte*) 0, record, &info->cur_row,
blocks, blocks->block->org_bitmap_value != 0,
&row_pos))
DBUG_RETURN(HA_OFFSET_ERROR); /* Error reading bitmap */
DBUG_PRINT("exit", ("Rowid: %lu", (ulong) info->cur_row.lastpos));
info->s->state.split++;
DBUG_RETURN(info->cur_row.lastpos);
}
/*
Dummy function for (*info->s->write_record)()
Nothing to do here, as we already wrote the record in
_ma_write_init_block_record()
*/
my_bool _ma_write_block_record(MARIA_HA *info __attribute__ ((unused)),
const byte *record __attribute__ ((unused)))
{
return 0; /* Row already written */
}
/**
@brief Remove row written by _ma_write_block_record()
@param info Maria handler
@note
This is called in case we got a duplicate unique key while
writing keys.
@return Operation status
@retval 0 OK
@retval 1 Error
*/
my_bool _ma_write_abort_block_record(MARIA_HA *info)
{
my_bool res= 0;
MARIA_BITMAP_BLOCKS *blocks= &info->cur_row.insert_blocks;
MARIA_BITMAP_BLOCK *block, *end;
DBUG_ENTER("_ma_abort_write_block_record");
if (delete_head_or_tail(info,
ma_recordpos_to_page(info->cur_row.lastpos),
ma_recordpos_to_dir_entry(info->cur_row.lastpos), 1))
res= 1;
for (block= blocks->block + 1, end= block + blocks->count - 1; block < end;
block++)
{
if (block->used & BLOCKUSED_TAIL)
{
/*
block->page_count is set to the tail directory entry number in
write_block_record()
*/
if (delete_head_or_tail(info, block->page, block->page_count & ~TAIL_BIT,
0))
res= 1;
}
else if (block->used & BLOCKUSED_USED)
{
if (free_full_page_range(info, block->page, block->page_count))
res= 1;
}
}
if (info->s->now_transactional)
{
LSN lsn;
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 1];
uchar log_data[LSN_STORE_SIZE + FILEID_STORE_SIZE];
/*
Write UNDO record
This entry is just an end marker for the abort_insert as we will never
really undo a failed insert. Note that this UNDO will cause recover
to ignore the LOGREC_UNDO_ROW_INSERT that is the previous entry
in the UNDO chain.
*/
/**
@todo RECOVERY BUG
We do need the code above (delete_head_or_tail() etc) for
non-transactional tables.
For transactional tables we can either also use it or execute the
UNDO_INSERT. If we crash before this
_ma_write_abort_block_record(), Recovery will do the work of this
function by executing UNDO_INSERT.
For transactional tables, we will remove this LOGREC_UNDO_PURGE and
replace it with a LOGREC_CLR_END: we should go back the UNDO chain
until we reach the UNDO which inserted the row into the data file, and
use its previous_undo_lsn.
Same logic for when we remove inserted keys (in case of error in
maria_write(): we come to the present function only after removing the
inserted keys... as long as we unpin the key pages only after writing
the CLR_END, this would be recovery-safe...).
*/
lsn_store(log_data, info->trn->undo_lsn);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
if (translog_write_record(&lsn, LOGREC_UNDO_ROW_PURGE,
info->trn, info->s, sizeof(log_data),
TRANSLOG_INTERNAL_PARTS + 1, log_array,
log_data + LSN_STORE_SIZE))
res= 1;
}
_ma_unpin_all_pages(info, info->trn->undo_lsn);
DBUG_RETURN(res);
}
/*
Update a record
NOTES
For the moment, we assume that info->curr_row.extents is always updated
when a row is read. In the future we may decide to read this on demand
for rows split into many extents.
*/
my_bool _ma_update_block_record(MARIA_HA *info, MARIA_RECORD_POS record_pos,
const byte *oldrec, const byte *record)
{
MARIA_BITMAP_BLOCKS *blocks= &info->cur_row.insert_blocks;
byte *buff;
MARIA_ROW *cur_row= &info->cur_row, *new_row= &info->new_row;
MARIA_PINNED_PAGE page_link;
uint rownr, org_empty_size, head_length;
uint block_size= info->s->block_size;
byte *dir;
ulonglong page;
struct st_row_pos_info row_pos;
MARIA_SHARE *share= info->s;
my_bool res;
DBUG_ENTER("_ma_update_block_record");
DBUG_PRINT("enter", ("rowid: %lu", (long) record_pos));
calc_record_size(info, record, new_row);
page= ma_recordpos_to_page(record_pos);
DBUG_ASSERT(share->pagecache->block_size == block_size);
if (!(buff= pagecache_read(share->pagecache,
&info->dfile, (my_off_t) page, 0,
info->buff, share->page_type,
PAGECACHE_LOCK_WRITE, &page_link.link)))
DBUG_RETURN(1);
page_link.unlock= PAGECACHE_LOCK_WRITE_UNLOCK;
push_dynamic(&info->pinned_pages, (void*) &page_link);
org_empty_size= uint2korr(buff + EMPTY_SPACE_OFFSET);
rownr= ma_recordpos_to_dir_entry(record_pos);
dir= (buff + block_size - DIR_ENTRY_SIZE * rownr -
DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE);
if ((org_empty_size + cur_row->head_length) >= new_row->total_length)
{
uint empty, offset, length;
MARIA_BITMAP_BLOCK block;
/*
We can fit the new row in the same page as the original head part
of the row
*/
block.org_bitmap_value= _ma_free_size_to_head_pattern(&share->bitmap,
org_empty_size);
offset= uint2korr(dir);
length= uint2korr(dir + 2);
empty= 0;
if (new_row->total_length > length)
{
/* See if there is empty space after */
if (rownr != (uint) ((uchar *) buff)[DIR_COUNT_OFFSET] - 1)
empty= start_of_next_entry(dir) - (offset + length);
if (new_row->total_length > length + empty)
{
compact_page(buff, share->block_size, rownr, 1);
org_empty_size= 0;
length= uint2korr(dir + 2);
}
}
row_pos.buff= buff;
row_pos.rownr= rownr;
row_pos.empty_space= org_empty_size + length;
row_pos.dir= dir;
row_pos.data= buff + uint2korr(dir);
row_pos.length= length + empty;
blocks->block= &block;
blocks->count= 1;
block.page= page;
block.sub_blocks= 1;
block.used= BLOCKUSED_USED | BLOCKUSED_USE_ORG_BITMAP;
block.empty_space= row_pos.empty_space;
/* Update cur_row, if someone calls update at once again */
cur_row->head_length= new_row->total_length;
if (free_full_pages(info, cur_row))
goto err;
DBUG_RETURN(write_block_record(info, oldrec, record, new_row, blocks,
1, &row_pos));
}
/*
Allocate all size in block for record
QQ: Need to improve this to do compact if we can fit one more blob into
the head page
*/
head_length= uint2korr(dir + 2);
if (buff[PAGE_TYPE_OFFSET] & PAGE_CAN_BE_COMPACTED && org_empty_size &&
(head_length < new_row->head_length ||
(new_row->total_length <= head_length &&
org_empty_size + head_length >= new_row->total_length)))
{
compact_page(buff, share->block_size, rownr, 1);
org_empty_size= 0;
head_length= uint2korr(dir + 2);
}
/* Delete old row */
if (delete_tails(info, cur_row->tail_positions))
goto err;
if (free_full_pages(info, cur_row))
goto err;
if (_ma_bitmap_find_new_place(info, new_row, page, head_length, blocks))
goto err;
row_pos.buff= buff;
row_pos.rownr= rownr;
row_pos.empty_space= org_empty_size + head_length;
row_pos.dir= dir;
row_pos.data= buff + uint2korr(dir);
row_pos.length= head_length;
res= write_block_record(info, oldrec, record, new_row, blocks, 1, &row_pos);
DBUG_RETURN(res);
err:
_ma_unpin_all_pages(info, 0);
DBUG_RETURN(1);
}
/*
Delete a directory entry
SYNOPSIS
delete_dir_entry()
buff Page buffer
block_size Block size
record_number Record number to delete
empty_space Empty space on page after delete
RETURN
-1 Error on page
0 ok
1 Page is now empty
*/
static int delete_dir_entry(byte *buff, uint block_size, uint record_number,
uint *empty_space_res)
{
uint number_of_records= (uint) ((uchar *) buff)[DIR_COUNT_OFFSET];
uint length, empty_space;
byte *dir;
DBUG_ENTER("delete_dir_entry");
#ifdef SANITY_CHECKS
if (record_number >= number_of_records ||
record_number > ((block_size - LSN_SIZE - PAGE_TYPE_SIZE - 1 -
PAGE_SUFFIX_SIZE) / DIR_ENTRY_SIZE))
{
DBUG_PRINT("error", ("record_number: %u number_of_records: %u",
record_number, number_of_records));
DBUG_RETURN(-1);
}
#endif
empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
dir= (buff + block_size - DIR_ENTRY_SIZE * record_number -
DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE);
dir[0]= dir[1]= 0; /* Delete entry */
length= uint2korr(dir + 2);
if (record_number == number_of_records - 1)
{
/* Delete this entry and all following empty directory entries */
byte *end= buff + block_size - PAGE_SUFFIX_SIZE;
do
{
number_of_records--;
dir+= DIR_ENTRY_SIZE;
empty_space+= DIR_ENTRY_SIZE;
} while (dir < end && dir[0] == 0 && dir[1] == 0);
buff[DIR_COUNT_OFFSET]= (byte) (uchar) number_of_records;
}
empty_space+= length;
if (number_of_records != 0)
{
/* Update directory */
int2store(buff + EMPTY_SPACE_OFFSET, empty_space);
buff[PAGE_TYPE_OFFSET]|= (byte) PAGE_CAN_BE_COMPACTED;
*empty_space_res= empty_space;
DBUG_RETURN(0);
}
buff[PAGE_TYPE_OFFSET]= UNALLOCATED_PAGE;
*empty_space_res= block_size;
DBUG_RETURN(1);
}
/*
Delete a head a tail part
SYNOPSIS
delete_head_or_tail()
info Maria handler
page Page (not file offset!) on which the row is
head 1 if this is a head page
NOTES
Uses info->keyread_buff
RETURN
0 ok
1 error
*/
static my_bool delete_head_or_tail(MARIA_HA *info,
ulonglong page, uint record_number,
my_bool head)
{
MARIA_SHARE *share= info->s;
uint empty_space;
uint block_size= share->block_size;
byte *buff;
LSN lsn;
MARIA_PINNED_PAGE page_link;
int res;
DBUG_ENTER("delete_head_or_tail");
info->keyread_buff_used= 1;
DBUG_ASSERT(info->s->pagecache->block_size == block_size);
if (!(buff= pagecache_read(share->pagecache,
&info->dfile, page, 0,
info->keyread_buff,
info->s->page_type,
PAGECACHE_LOCK_WRITE, &page_link.link)))
DBUG_RETURN(1);
page_link.unlock= PAGECACHE_LOCK_WRITE_UNLOCK;
push_dynamic(&info->pinned_pages, (void*) &page_link);
res= delete_dir_entry(buff, block_size, record_number, &empty_space);
if (res < 0)
DBUG_RETURN(1);
if (res == 0) /* after our deletion, page is still not empty */
{
uchar log_data[FILEID_STORE_SIZE + PAGE_STORE_SIZE + DIRPOS_STORE_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 1];
if (info->s->now_transactional)
{
/* Log REDO data */
page_store(log_data+ FILEID_STORE_SIZE, page);
dirpos_store(log_data+ FILEID_STORE_SIZE + PAGE_STORE_SIZE,
record_number);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
if (translog_write_record(&lsn, (head ? LOGREC_REDO_PURGE_ROW_HEAD :
LOGREC_REDO_PURGE_ROW_TAIL),
info->trn, share, sizeof(log_data),
TRANSLOG_INTERNAL_PARTS + 1, log_array,
log_data))
DBUG_RETURN(1);
}
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, share->page_type,
PAGECACHE_LOCK_WRITE_TO_READ,
PAGECACHE_PIN_LEFT_PINNED,
PAGECACHE_WRITE_DELAY, &page_link.link))
DBUG_RETURN(1);
}
else /* page is now empty */
{
if (info->s->now_transactional)
{
uchar log_data[FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE +
PAGE_STORE_SIZE + PAGERANGE_STORE_SIZE];
LEX_STRING log_array[TRANSLOG_INTERNAL_PARTS + 1];
pagerange_store(log_data + FILEID_STORE_SIZE, 1);
page_store(log_data+ FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE, page);
pagerange_store(log_data + FILEID_STORE_SIZE + PAGERANGE_STORE_SIZE +
PAGE_STORE_SIZE, 1);
log_array[TRANSLOG_INTERNAL_PARTS + 0].str= (char*) log_data;
log_array[TRANSLOG_INTERNAL_PARTS + 0].length= sizeof(log_data);
if (translog_write_record(&lsn, LOGREC_REDO_PURGE_BLOCKS,
info->trn, share, sizeof(log_data),
TRANSLOG_INTERNAL_PARTS + 1, log_array,
log_data))
DBUG_RETURN(1);
}
/* Write the empty page (needed only for REPAIR to work) */
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, share->page_type,
PAGECACHE_LOCK_WRITE_TO_READ,
PAGECACHE_PIN_LEFT_PINNED,
PAGECACHE_WRITE_DELAY, &page_link.link))
DBUG_RETURN(1);
DBUG_ASSERT(empty_space >= info->s->bitmap.sizes[0]);
}
/* Change the lock used when we read the page */
page_link.unlock= PAGECACHE_LOCK_READ_UNLOCK;
set_dynamic(&info->pinned_pages, (void*) &page_link,
info->pinned_pages.elements-1);
DBUG_PRINT("info", ("empty_space: %u", empty_space));
DBUG_RETURN(_ma_bitmap_set(info, page, head, empty_space));
}
/*
delete all tails
SYNOPSIS
delete_tails()
info Handler
tails Pointer to vector of tail positions, ending with 0
NOTES
Uses info->keyread_buff
RETURN
0 ok
1 error
*/
static my_bool delete_tails(MARIA_HA *info, MARIA_RECORD_POS *tails)
{
my_bool res= 0;
DBUG_ENTER("delete_tails");
for (; *tails; tails++)
{
if (delete_head_or_tail(info,
ma_recordpos_to_page(*tails),
ma_recordpos_to_dir_entry(*tails), 0))
res= 1;
}
DBUG_RETURN(res);
}
/*
Delete a record
NOTES
For the moment, we assume that info->cur_row.extents is always updated
when a row is read. In the future we may decide to read this on demand
for rows with many splits.
*/
my_bool _ma_delete_block_record(MARIA_HA *info, const byte *record)
{
ulonglong page;
uint record_number;
DBUG_ENTER("_ma_delete_block_record");
page= ma_recordpos_to_page(info->cur_row.lastpos);
record_number= ma_recordpos_to_dir_entry(info->cur_row.lastpos);
if (delete_head_or_tail(info, page, record_number, 1) ||
delete_tails(info, info->cur_row.tail_positions))
goto err;
info->s->state.split--;
if (info->cur_row.extents && free_full_pages(info, &info->cur_row))
goto err;
if (info->s->now_transactional)
{
LSN lsn;
uchar log_data[LSN_STORE_SIZE + FILEID_STORE_SIZE + PAGE_STORE_SIZE +
DIR_COUNT_SIZE];
size_t row_length;
uint row_parts_count;
/* Write UNDO record */
lsn_store(log_data, info->trn->undo_lsn);
page_store(log_data+ LSN_STORE_SIZE + FILEID_STORE_SIZE, page);
dirpos_store(log_data+ LSN_STORE_SIZE + FILEID_STORE_SIZE +
PAGE_STORE_SIZE, record_number);
info->log_row_parts[TRANSLOG_INTERNAL_PARTS].str= (char*) log_data;
info->log_row_parts[TRANSLOG_INTERNAL_PARTS].length= sizeof(log_data);
row_length= fill_insert_undo_parts(info, record, info->log_row_parts +
TRANSLOG_INTERNAL_PARTS + 1,
&row_parts_count);
if (translog_write_record(&lsn, LOGREC_UNDO_ROW_DELETE, info->trn,
info->s, sizeof(log_data) + row_length,
TRANSLOG_INTERNAL_PARTS + 1 + row_parts_count,
info->log_row_parts, log_data + LSN_STORE_SIZE))
goto err;
}
_ma_unpin_all_pages(info, info->trn->undo_lsn);
DBUG_RETURN(0);
err:
_ma_unpin_all_pages(info, 0);
DBUG_RETURN(1);
}
/****************************************************************************
Reading of records
****************************************************************************/
/*
Read position to record from record directory at end of page
SYNOPSIS
get_record_position()
buff page buffer
block_size block size for page
record_number Record number in index
end_of_data pointer to end of data for record
RETURN
0 Error in data
# Pointer to start of record.
In this case *end_of_data is set.
*/
static byte *get_record_position(byte *buff, uint block_size,
uint record_number, byte **end_of_data)
{
uint number_of_records= (uint) ((uchar *) buff)[DIR_COUNT_OFFSET];
byte *dir;
byte *data;
uint offset, length;
#ifdef SANITY_CHECKS
if (record_number >= number_of_records ||
record_number > ((block_size - PAGE_HEADER_SIZE - PAGE_SUFFIX_SIZE) /
DIR_ENTRY_SIZE))
{
DBUG_PRINT("error",
("Wrong row number: record_number: %u number_of_records: %u",
record_number, number_of_records));
return 0;
}
#endif
dir= (buff + block_size - DIR_ENTRY_SIZE * record_number -
DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE);
offset= uint2korr(dir);
length= uint2korr(dir + 2);
#ifdef SANITY_CHECKS
if (offset < PAGE_HEADER_SIZE ||
offset + length > (block_size -
number_of_records * DIR_ENTRY_SIZE -
PAGE_SUFFIX_SIZE))
{
DBUG_PRINT("error",
("Wrong row position: record_number: %u offset: %u "
"length: %u number_of_records: %u",
record_number, offset, length, number_of_records));
return 0;
}
#endif
data= buff + offset;
*end_of_data= data + length;
return data;
}
/*
Init extent
NOTES
extent is a cursor over which pages to read
*/
static void init_extent(MARIA_EXTENT_CURSOR *extent, byte *extent_info,
uint extents, MARIA_RECORD_POS *tail_positions)
{
uint page_count;
extent->extent= extent_info;
extent->extent_count= extents;
extent->page= page_korr(extent_info); /* First extent */
page_count= uint2korr(extent_info + ROW_EXTENT_PAGE_SIZE);
extent->page_count= page_count & ~TAIL_BIT;
extent->tail= page_count & TAIL_BIT;
extent->tail_positions= tail_positions;
}
/*
Read next extent
SYNOPSIS
read_next_extent()
info Maria handler
extent Pointer to current extent (this is updated to point
to next)
end_of_data Pointer to end of data in read block (out)
NOTES
New block is read into info->buff
RETURN
0 Error; my_errno is set
# Pointer to start of data in read block
In this case end_of_data is updated to point to end of data.
*/
static byte *read_next_extent(MARIA_HA *info, MARIA_EXTENT_CURSOR *extent,
byte **end_of_data)
{
MARIA_SHARE *share= info->s;
byte *buff, *data;
DBUG_ENTER("read_next_extent");
if (!extent->page_count)
{
uint page_count;
if (!--extent->extent_count)
goto crashed;
extent->extent+= ROW_EXTENT_SIZE;
extent->page= page_korr(extent->extent);
page_count= uint2korr(extent->extent+ROW_EXTENT_PAGE_SIZE);
if (!page_count)
goto crashed;
extent->tail= page_count & TAIL_BIT;
extent->page_count= (page_count & ~TAIL_BIT);
extent->first_extent= 0;
DBUG_PRINT("info",("New extent. Page: %lu page_count: %u tail_flag: %d",
(ulong) extent->page, extent->page_count,
extent->tail != 0));
}
DBUG_ASSERT(share->pagecache->block_size == share->block_size);
if (!(buff= pagecache_read(share->pagecache,
&info->dfile, extent->page, 0,
info->buff, share->page_type,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
{
/* check if we tried to read over end of file (ie: bad data in record) */
if ((extent->page + 1) * share->block_size > info->state->data_file_length)
goto crashed;
DBUG_RETURN(0);
}
if (!extent->tail)
{
/* Full data page */
if ((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) != BLOB_PAGE)
goto crashed;
extent->page++; /* point to next page */
extent->page_count--;
*end_of_data= buff + share->block_size;
info->cur_row.full_page_count++; /* For maria_chk */
DBUG_RETURN(extent->data_start= buff + LSN_SIZE + PAGE_TYPE_SIZE);
}
/* Found tail. page_count is in this case the position in the tail page */
if ((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) != TAIL_PAGE)
goto crashed;
*(extent->tail_positions++)= ma_recordpos(extent->page,
extent->page_count);
info->cur_row.tail_count++; /* For maria_chk */
if (!(data= get_record_position(buff, share->block_size,
extent->page_count,
end_of_data)))
goto crashed;
extent->data_start= data;
extent->page_count= 0; /* No more data in extent */
DBUG_RETURN(data);
crashed:
my_errno= HA_ERR_WRONG_IN_RECORD; /* File crashed */
DBUG_PRINT("error", ("wrong extent information"));
DBUG_RETURN(0);
}
/*
Read data that may be split over many blocks
SYNOPSIS
read_long_data()
info Maria handler
to Store result string here (this is allocated)
extent Pointer to current extent position
data Current position in buffer
end_of_data End of data in buffer
NOTES
When we have to read a new buffer, it's read into info->buff
This loop is implemented by goto's instead of a for() loop as
the code is notable smaller and faster this way (and it's not nice
to jump into a for loop() or into a 'then' clause)
RETURN
0 ok
1 error
*/
static my_bool read_long_data(MARIA_HA *info, byte *to, ulong length,
MARIA_EXTENT_CURSOR *extent,
byte **data, byte **end_of_data)
{
DBUG_ENTER("read_long_data");
DBUG_PRINT("enter", ("length: %lu", length));
DBUG_ASSERT(*data <= *end_of_data);
/*
Fields are never split in middle. This means that if length > rest-of-data
we should start reading from the next extent. The reason we may have
data left on the page is that there fixed part of the row was less than
min_row_length and in this case the head block was extended to
min_row_length.
This may change in the future, which is why we have the loop written
the way it's written.
*/
if (length > (ulong) (*end_of_data - *data))
*end_of_data= *data;
for(;;)
{
uint left_length;
left_length= (uint) (*end_of_data - *data);
if (likely(left_length >= length))
{
memcpy(to, *data, length);
(*data)+= length;
DBUG_RETURN(0);
}
memcpy(to, *data, left_length);
to+= left_length;
length-= left_length;
if (!(*data= read_next_extent(info, extent, end_of_data)))
break;
}
DBUG_RETURN(1);
}
/*
Read a record from page (helper function for _ma_read_block_record())
SYNOPSIS
_ma_read_block_record2()
info Maria handler
record Store record here
data Start of head data for row
end_of_data End of data for row
NOTES
The head page is already read by caller
Following data is update in info->cur_row:
cur_row.head_length is set to size of entry in head block
cur_row.tail_positions is set to point to all tail blocks
cur_row.extents points to extents data
cur_row.extents_counts contains number of extents
cur_row.empty_bits is set to empty bits
cur_row.field_lengths contains packed length of all fields
RETURN
0 ok
# Error code
*/
int _ma_read_block_record2(MARIA_HA *info, byte *record,
byte *data, byte *end_of_data)
{
MARIA_SHARE *share= info->s;
byte *field_length_data, *blob_buffer, *start_of_data;
uint flag, null_bytes, cur_null_bytes, row_extents, field_lengths;
my_bool found_blob= 0;
MARIA_EXTENT_CURSOR extent;
MARIA_COLUMNDEF *column, *end_column;
DBUG_ENTER("_ma_read_block_record2");
LINT_INIT(field_length_data);
LINT_INIT(blob_buffer);
start_of_data= data;
flag= (uint) (uchar) data[0];
cur_null_bytes= share->base.original_null_bytes;
null_bytes= share->base.null_bytes;
info->cur_row.head_length= (uint) (end_of_data - data);
info->cur_row.full_page_count= info->cur_row.tail_count= 0;
/* Skip trans header (for now, until we have MVCC csupport) */
data+= total_header_size[(flag & PRECALC_HEADER_BITMASK)];
if (flag & ROW_FLAG_NULLS_EXTENDED)
cur_null_bytes+= data[-1];
row_extents= 0;
if (flag & ROW_FLAG_EXTENTS)
{
uint row_extent_size;
/*
Record is split over many data pages.
Get number of extents and first extent
*/
get_key_length(row_extents, data);
info->cur_row.extents_count= row_extents;
row_extent_size= row_extents * ROW_EXTENT_SIZE;
if (info->cur_row.extents_buffer_length < row_extent_size &&
_ma_alloc_buffer(&info->cur_row.extents,
&info->cur_row.extents_buffer_length,
row_extent_size))
DBUG_RETURN(my_errno);
memcpy(info->cur_row.extents, data, ROW_EXTENT_SIZE);
data+= ROW_EXTENT_SIZE;
init_extent(&extent, info->cur_row.extents, row_extents,
info->cur_row.tail_positions);
}
else
{
info->cur_row.extents_count= 0;
(*info->cur_row.tail_positions)= 0;
extent.page_count= 0;
extent.extent_count= 1;
}
extent.first_extent= 1;
field_lengths= 0;
if (share->base.max_field_lengths)
{
get_key_length(field_lengths, data);
info->cur_row.field_lengths_length= field_lengths;
#ifdef SANITY_CHECKS
if (field_lengths > share->base.max_field_lengths)
goto err;
#endif
}
if (share->calc_checksum)
info->cur_row.checksum= (uint) (uchar) *data++;
/* data now points on null bits */
memcpy(record, data, cur_null_bytes);
if (unlikely(cur_null_bytes != null_bytes))
{
/*
This only happens if we have added more NULL columns with
ALTER TABLE and are fetching an old, not yet modified old row
*/
bzero(record + cur_null_bytes, (uint) (null_bytes - cur_null_bytes));
}
data+= null_bytes;
/* We copy the empty bits to be able to use them for delete/update */
memcpy(info->cur_row.empty_bits, data, share->base.pack_bytes);
data+= share->base.pack_bytes;
/* TODO: Use field offsets, instead of just skipping them */
data+= share->base.field_offsets * FIELD_OFFSET_SIZE;
/*
Read row extents (note that first extent was already read into
info->cur_row.extents above)
*/
if (row_extents > 1)
{
if (read_long_data(info, info->cur_row.extents + ROW_EXTENT_SIZE,
(row_extents - 1) * ROW_EXTENT_SIZE,
&extent, &data, &end_of_data))
DBUG_RETURN(my_errno);
}
/*
Data now points to start of fixed length field data that can't be null
or 'empty'. Note that these fields can't be split over blocks.
*/
for (column= share->columndef,
end_column= column + share->base.fixed_not_null_fields;
column < end_column; column++)
{
uint column_length= column->length;
if (data >= end_of_data &&
!(data= read_next_extent(info, &extent, &end_of_data)))
goto err;
memcpy(record + column->offset, data, column_length);
data+= column_length;
}
/* Read array of field lengths. This may be stored in several extents */
if (field_lengths)
{
field_length_data= info->cur_row.field_lengths;
if (read_long_data(info, field_length_data, field_lengths, &extent,
&data, &end_of_data))
DBUG_RETURN(my_errno);
}
/* Read variable length data. Each of these may be split over many extents */
for (end_column= share->columndef + share->base.fields;
column < end_column; column++)
{
enum en_fieldtype type= (enum en_fieldtype) column->type;
byte *field_pos= record + column->offset;
/* First check if field is present in record */
if ((record[column->null_pos] & column->null_bit) ||
(info->cur_row.empty_bits[column->empty_pos] & column->empty_bit))
{
if (type == FIELD_SKIP_ENDSPACE)
bfill(record + column->offset, column->length, ' ');
else
bzero(record + column->offset, column->fill_length);
continue;
}
switch (type) {
case FIELD_NORMAL: /* Fixed length field */
case FIELD_SKIP_PRESPACE:
case FIELD_SKIP_ZERO: /* Fixed length field */
if (data >= end_of_data &&
!(data= read_next_extent(info, &extent, &end_of_data)))
goto err;
memcpy(field_pos, data, column->length);
data+= column->length;
break;
case FIELD_SKIP_ENDSPACE: /* CHAR */
{
/* Char that is space filled */
uint length;
if (column->length <= 255)
length= (uint) (uchar) *field_length_data++;
else
{
length= uint2korr(field_length_data);
field_length_data+= 2;
}
#ifdef SANITY_CHECKS
if (length > column->length)
goto err;
#endif
if (read_long_data(info, field_pos, length, &extent, &data,
&end_of_data))
DBUG_RETURN(my_errno);
bfill(field_pos + length, column->length - length, ' ');
break;
}
case FIELD_VARCHAR:
{
ulong length;
if (column->length <= 256)
{
length= (uint) (uchar) (*field_pos++= *field_length_data++);
}
else
{
length= uint2korr(field_length_data);
field_pos[0]= field_length_data[0];
field_pos[1]= field_length_data[1];
field_pos+= 2;
field_length_data+= 2;
}
if (read_long_data(info, field_pos, length, &extent, &data,
&end_of_data))
DBUG_RETURN(my_errno);
break;
}
case FIELD_BLOB:
{
uint size_length= column->length - portable_sizeof_char_ptr;
ulong blob_length= _ma_calc_blob_length(size_length, field_length_data);
if (!found_blob)
{
/* Calculate total length for all blobs */
ulong blob_lengths= 0;
byte *length_data= field_length_data;
MARIA_COLUMNDEF *blob_field= column;
found_blob= 1;
for (; blob_field < end_column; blob_field++)
{
uint size_length;
if ((record[blob_field->null_pos] & blob_field->null_bit) ||
(info->cur_row.empty_bits[blob_field->empty_pos] &
blob_field->empty_bit))
continue;
size_length= blob_field->length - portable_sizeof_char_ptr;
blob_lengths+= _ma_calc_blob_length(size_length, length_data);
length_data+= size_length;
}
DBUG_PRINT("info", ("Total blob length: %lu", blob_lengths));
if (_ma_alloc_buffer(&info->rec_buff, &info->rec_buff_size,
blob_lengths))
DBUG_RETURN(my_errno);
blob_buffer= info->rec_buff;
}
memcpy(field_pos, field_length_data, size_length);
memcpy_fixed(field_pos + size_length, (byte *) & blob_buffer,
sizeof(char*));
field_length_data+= size_length;
/*
After we have read one extent, then each blob is in it's own extent
*/
if (extent.first_extent && (ulong) (end_of_data - data) < blob_length)
end_of_data= data; /* Force read of next extent */
if (read_long_data(info, blob_buffer, blob_length, &extent, &data,
&end_of_data))
DBUG_RETURN(my_errno);
blob_buffer+= blob_length;
break;
}
default:
#ifdef EXTRA_DEBUG
DBUG_ASSERT(0); /* purecov: deadcode */
#endif
goto err;
}
continue;
}
if (row_extents)
{
DBUG_PRINT("info", ("Row read: page_count: %u extent_count: %u",
extent.page_count, extent.extent_count));
*extent.tail_positions= 0; /* End marker */
if (extent.page_count)
goto err;
if (extent.extent_count > 1)
if (check_if_zero(extent.extent + ROW_EXTENT_SIZE,
(extent.extent_count-1) * ROW_EXTENT_SIZE))
goto err;
}
else
{
DBUG_PRINT("info", ("Row read"));
/*
data should normally point to end_of_date. The only exception is if
the row is very short in which case we allocated 'min_row_length' data
for allowing the row to expand.
*/
if (data != end_of_data && (uint) (end_of_data - start_of_data) >
info->s->base.min_row_length)
goto err;
}
info->update|= HA_STATE_AKTIV; /* We have an active record */
DBUG_RETURN(0);
err:
/* Something was wrong with data on record */
DBUG_PRINT("error", ("Found record with wrong data"));
DBUG_RETURN((my_errno= HA_ERR_WRONG_IN_RECORD));
}
/*
Read a record based on record position
SYNOPSIS
_ma_read_block_record()
info Maria handler
record Store record here
record_pos Record position
*/
int _ma_read_block_record(MARIA_HA *info, byte *record,
MARIA_RECORD_POS record_pos)
{
byte *data, *end_of_data, *buff;
uint offset;
uint block_size= info->s->block_size;
DBUG_ENTER("_ma_read_block_record");
DBUG_PRINT("enter", ("rowid: %lu", (long) record_pos));
info->cur_row.lastpos= record_pos;
offset= ma_recordpos_to_dir_entry(record_pos);
DBUG_ASSERT(info->s->pagecache->block_size == block_size);
if (!(buff= pagecache_read(info->s->pagecache,
&info->dfile, ma_recordpos_to_page(record_pos), 0,
info->buff, info->s->page_type,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(1);
DBUG_ASSERT((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) == HEAD_PAGE);
if (!(data= get_record_position(buff, block_size, offset, &end_of_data)))
{
my_errno= HA_ERR_WRONG_IN_RECORD; /* File crashed */
DBUG_PRINT("error", ("Wrong directory entry in data block"));
DBUG_RETURN(1);
}
DBUG_RETURN(_ma_read_block_record2(info, record, data, end_of_data));
}
/* compare unique constraint between stored rows */
my_bool _ma_cmp_block_unique(MARIA_HA *info, MARIA_UNIQUEDEF *def,
const byte *record, MARIA_RECORD_POS pos)
{
byte *org_rec_buff, *old_record;
my_size_t org_rec_buff_size;
int error;
DBUG_ENTER("_ma_cmp_block_unique");
if (!(old_record= my_alloca(info->s->base.reclength)))
DBUG_RETURN(1);
/* Don't let the compare destroy blobs that may be in use */
org_rec_buff= info->rec_buff;
org_rec_buff_size= info->rec_buff_size;
if (info->s->base.blobs)
{
/* Force realloc of record buffer*/
info->rec_buff= 0;
info->rec_buff_size= 0;
}
error= _ma_read_block_record(info, old_record, pos);
if (!error)
error= _ma_unique_comp(def, record, old_record, def->null_are_equal);
if (info->s->base.blobs)
{
my_free(info->rec_buff, MYF(MY_ALLOW_ZERO_PTR));
info->rec_buff= org_rec_buff;
info->rec_buff_size= org_rec_buff_size;
}
DBUG_PRINT("exit", ("result: %d", error));
my_afree(old_record);
DBUG_RETURN(error != 0);
}
/****************************************************************************
Table scan
****************************************************************************/
/*
Allocate buffers for table scan
SYNOPSIS
_ma_scan_init_block_record(MARIA_HA *info)
IMPLEMENTATION
We allocate one buffer for the current bitmap and one buffer for the
current page
RETURN
0 ok
1 error (couldn't allocate memory or disk error)
*/
my_bool _ma_scan_init_block_record(MARIA_HA *info)
{
DBUG_ENTER("_ma_scan_init_block_record");
/*
bitmap_buff may already be allocated if this is the second call to
rnd_init() without a rnd_end() in between, see sql/handler.h
*/
if (!(info->scan.bitmap_buff ||
((info->scan.bitmap_buff=
(byte *) my_malloc(info->s->block_size * 2, MYF(MY_WME))))))
DBUG_RETURN(1);
info->scan.page_buff= info->scan.bitmap_buff + info->s->block_size;
info->scan.bitmap_end= info->scan.bitmap_buff + info->s->bitmap.total_size;
/* Set scan variables to get _ma_scan_block() to start with reading bitmap */
info->scan.number_of_rows= 0;
info->scan.bitmap_pos= info->scan.bitmap_end;
info->scan.bitmap_page= (ulong) - (long) info->s->bitmap.pages_covered;
/*
We have to flush bitmap as we will read the bitmap from the page cache
while scanning rows
*/
DBUG_RETURN(_ma_flush_bitmap(info->s));
}
/* Free buffers allocated by _ma_scan_block_init() */
void _ma_scan_end_block_record(MARIA_HA *info)
{
DBUG_ENTER("_ma_scan_end_block_record");
my_free(info->scan.bitmap_buff, MYF(MY_ALLOW_ZERO_PTR));
info->scan.bitmap_buff= 0;
DBUG_VOID_RETURN;
}
/*
Read next record while scanning table
SYNOPSIS
_ma_scan_block_record()
info Maria handler
record Store found here
record_pos Value stored in info->cur_row.next_pos after last call
skip_deleted
NOTES
- One must have called mi_scan() before this
- In this version, we don't actually need record_pos, we as easily
use a variable in info->scan
IMPLEMENTATION
Current code uses a lot of goto's to separate the different kind of
states we may be in. This gives us a minimum of executed if's for
the normal cases. I tried several different ways to code this, but
the current one was in the end the most readable and fastest.
RETURN
0 ok
# Error code
*/
int _ma_scan_block_record(MARIA_HA *info, byte *record,
MARIA_RECORD_POS record_pos,
my_bool skip_deleted __attribute__ ((unused)))
{
uint block_size;
my_off_t filepos;
MARIA_SHARE *share= info->s;
DBUG_ENTER("_ma_scan_block_record");
restart_record_read:
/* Find next row in current page */
if (likely(record_pos < info->scan.number_of_rows))
{
uint length, offset;
byte *data, *end_of_data;
while (!(offset= uint2korr(info->scan.dir)))
{
info->scan.dir-= DIR_ENTRY_SIZE;
record_pos++;
#ifdef SANITY_CHECKS
if (info->scan.dir < info->scan.dir_end)
goto err;
#endif
}
/* found row */
info->cur_row.lastpos= info->scan.row_base_page + record_pos;
info->cur_row.nextpos= record_pos + 1;
data= info->scan.page_buff + offset;
length= uint2korr(info->scan.dir + 2);
end_of_data= data + length;
info->scan.dir-= DIR_ENTRY_SIZE; /* Point to previous row */
#ifdef SANITY_CHECKS
if (end_of_data > info->scan.dir_end ||
offset < PAGE_HEADER_SIZE || length < share->base.min_block_length)
goto err;
#endif
DBUG_PRINT("info", ("rowid: %lu", (ulong) info->cur_row.lastpos));
DBUG_RETURN(_ma_read_block_record2(info, record, data, end_of_data));
}
/* Find next head page in current bitmap */
restart_bitmap_scan:
block_size= share->block_size;
if (likely(info->scan.bitmap_pos < info->scan.bitmap_end))
{
byte *data= info->scan.bitmap_pos;
longlong bits= info->scan.bits;
uint bit_pos= info->scan.bit_pos;
do
{
while (likely(bits))
{
uint pattern= bits & 7;
bits >>= 3;
bit_pos++;
if (pattern > 0 && pattern <= 4)
{
/* Found head page; Read it */
ulong page;
info->scan.bitmap_pos= data;
info->scan.bits= bits;
info->scan.bit_pos= bit_pos;
page= (info->scan.bitmap_page + 1 +
(data - info->scan.bitmap_buff) / 6 * 16 + bit_pos - 1);
info->scan.row_base_page= ma_recordpos(page, 0);
if (!(pagecache_read(share->pagecache,
&info->dfile,
page, 0, info->scan.page_buff,
share->page_type,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(my_errno);
if (((info->scan.page_buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) !=
HEAD_PAGE) ||
(info->scan.number_of_rows=
(uint) (uchar) info->scan.page_buff[DIR_COUNT_OFFSET]) == 0)
{
DBUG_PRINT("error", ("Wrong page header"));
DBUG_RETURN((my_errno= HA_ERR_WRONG_IN_RECORD));
}
DBUG_PRINT("info", ("Page %lu has %u rows",
(ulong) page, info->scan.number_of_rows));
info->scan.dir= (info->scan.page_buff + block_size -
PAGE_SUFFIX_SIZE - DIR_ENTRY_SIZE);
info->scan.dir_end= (info->scan.dir -
(info->scan.number_of_rows - 1) *
DIR_ENTRY_SIZE);
record_pos= 0;
goto restart_record_read;
}
}
for (data+= 6; data < info->scan.bitmap_end; data+= 6)
{
bits= uint6korr(data);
/* Skip not allocated pages and blob / full tail pages */
if (bits && bits != LL(07777777777777777))
break;
}
bit_pos= 0;
} while (data < info->scan.bitmap_end);
}
/* Read next bitmap */
info->scan.bitmap_page+= share->bitmap.pages_covered;
filepos= (my_off_t) info->scan.bitmap_page * block_size;
if (unlikely(filepos >= info->state->data_file_length))
{
DBUG_PRINT("info", ("Found end of file"));
DBUG_RETURN((my_errno= HA_ERR_END_OF_FILE));
}
DBUG_PRINT("info", ("Reading bitmap at %lu",
(ulong) info->scan.bitmap_page));
if (!(pagecache_read(share->pagecache, &info->dfile,
info->scan.bitmap_page,
0, info->scan.bitmap_buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(my_errno);
/* Skip scanning 'bits' in bitmap scan code */
info->scan.bitmap_pos= info->scan.bitmap_buff - 6;
info->scan.bits= 0;
goto restart_bitmap_scan;
err:
DBUG_PRINT("error", ("Wrong data on page"));
DBUG_RETURN((my_errno= HA_ERR_WRONG_IN_RECORD));
}
/*
Compare a row against a stored one
NOTES
Not implemented, as block record is not supposed to be used in a shared
global environment
*/
my_bool _ma_compare_block_record(MARIA_HA *info __attribute__ ((unused)),
const byte *record __attribute__ ((unused)))
{
return 0;
}
#ifndef DBUG_OFF
static void _ma_print_directory(byte *buff, uint block_size)
{
uint max_entry= (uint) ((uchar *) buff)[DIR_COUNT_OFFSET], row= 0;
uint end_of_prev_row= PAGE_HEADER_SIZE;
byte *dir, *end;
dir= buff + block_size - DIR_ENTRY_SIZE * max_entry - PAGE_SUFFIX_SIZE;
end= buff + block_size - DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE;
DBUG_LOCK_FILE;
fprintf(DBUG_FILE,"Directory dump (pos:length):\n");
for (row= 1; dir <= end ; end-= DIR_ENTRY_SIZE, row++)
{
uint offset= uint2korr(end);
uint length= uint2korr(end+2);
fprintf(DBUG_FILE, " %4u:%4u", offset, offset ? length : 0);
if (!(row % (80/12)))
fputc('\n', DBUG_FILE);
if (offset)
{
DBUG_ASSERT(offset >= end_of_prev_row);
end_of_prev_row= offset + length;
}
}
fputc('\n', DBUG_FILE);
fflush(DBUG_FILE);
DBUG_UNLOCK_FILE;
}
#endif /* DBUG_OFF */
/*
Store an integer with simple packing
SYNOPSIS
ma_store_integer()
to Store the packed integer here
nr Integer to store
NOTES
This is mostly used to store field numbers and lengths of strings.
We have to cast the result for the LL() becasue of a bug in Forte CC
compiler.
Packing used is:
nr < 251 is stored as is (in 1 byte)
Numbers that require 1-4 bytes are stored as char(250+byte_length), data
Bigger numbers are stored as 255, data as ulonglong (not yet done).
RETURN
Position in 'to' after the packed length
*/
uchar *ma_store_length(uchar *to, ulong nr)
{
if (nr < 251)
{
*to=(uchar) nr;
return to+1;
}
if (nr < 65536)
{
if (nr <= 255)
{
to[0]= (uchar) 251;
to[1]= (uchar) nr;
return to+2;
}
to[0]= (uchar) 252;
int2store(to+1, nr);
return to+3;
}
if (nr < 16777216)
{
*to++= (uchar) 253;
int3store(to, nr);
return to+3;
}
*to++= (uchar) 254;
int4store(to, nr);
return to+4;
}
/* Calculate how many bytes needed to store a number */
uint ma_calc_length_for_store_length(ulong nr)
{
if (nr < 251)
return 1;
if (nr < 65536)
{
if (nr <= 255)
return 2;
return 3;
}
if (nr < 16777216)
return 4;
return 5;
}
/*
Fill array with pointers to field parts to be stored in log for insert
SYNOPSIS
fill_insert_undo_parts()
info Maria handler
record Inserted row
log_parts Store pointers to changed memory areas here
log_parts_count See RETURN
NOTES
We have information in info->cur_row about the read row.
RETURN
length of data in log_parts.
log_parts_count contains number of used log_parts
*/
static size_t fill_insert_undo_parts(MARIA_HA *info, const byte *record,
LEX_STRING *log_parts,
uint *log_parts_count)
{
MARIA_SHARE *share= info->s;
MARIA_COLUMNDEF *column, *end_column;
uchar *field_lengths= info->cur_row.field_lengths;
size_t row_length;
MARIA_ROW *cur_row= &info->cur_row;
LEX_STRING *start_log_parts;
DBUG_ENTER("fill_insert_undo_parts");
start_log_parts= log_parts;
/* Store null bits */
log_parts->str= (char*) record;
log_parts->length= share->base.null_bytes;
row_length= log_parts->length;
log_parts++;
/* Stored bitmap over packed (zero length or all-zero fields) */
log_parts->str= info->cur_row.empty_bits;
log_parts->length= share->base.pack_bytes;
row_length+= log_parts->length;
log_parts++;
if (share->base.max_field_lengths)
{
/* Store field lenghts, with a prefix of number of bytes */
log_parts->str= field_lengths-2;
log_parts->length= info->cur_row.field_lengths_length+2;
int2store(log_parts->str, info->cur_row.field_lengths_length);
row_length+= log_parts->length;
log_parts++;
}
/* Handle constant length fields that are always present */
for (column= share->columndef,
end_column= column+ share->base.fixed_not_null_fields;
column < end_column;
column++)
{
log_parts->str= (char*) record + column->offset;
log_parts->length= column->length;
row_length+= log_parts->length;
log_parts++;
}
/* Handle NULL fields and CHAR/VARCHAR fields */
for (end_column= share->columndef + share->base.fields - share->base.blobs;
column < end_column;
column++)
{
const uchar *column_pos;
size_t column_length;
if ((record[column->null_pos] & column->null_bit) ||
cur_row->empty_bits[column->empty_pos] & column->empty_bit)
continue;
column_pos= record+ column->offset;
column_length= column->length;
switch ((enum en_fieldtype) column->type) {
case FIELD_CHECK:
case FIELD_NORMAL: /* Fixed length field */
case FIELD_ZERO:
case FIELD_SKIP_PRESPACE: /* Not packed */
case FIELD_SKIP_ZERO: /* Fixed length field */
break;
case FIELD_SKIP_ENDSPACE: /* CHAR */
{
if (column->length <= 255)
column_length= *field_lengths++;
else
{
column_length= uint2korr(field_lengths);
field_lengths+= 2;
}
break;
}
case FIELD_VARCHAR:
{
if (column->length <= 256)
{
column_length= *field_lengths;
field_lengths++;
}
else
{
column_length= uint2korr(field_lengths);
field_lengths+= 2;
}
break;
}
default:
DBUG_ASSERT(0);
}
log_parts->str= (char*) column_pos;
log_parts->length= column_length;
row_length+= log_parts->length;
log_parts++;
}
/* Add blobs */
for (end_column+= share->base.blobs; column < end_column; column++)
{
const byte *field_pos= record + column->offset;
uint size_length= column->length - portable_sizeof_char_ptr;
ulong blob_length= _ma_calc_blob_length(size_length, field_pos);
/*
We don't have to check for null, as blob_length is guranteed to be 0
if the blob is null
*/
if (blob_length)
{
char *blob_pos;
memcpy_fixed((byte*) &blob_pos, record + column->offset + size_length,
sizeof(blob_pos));
log_parts->str= blob_pos;
log_parts->length= blob_length;
row_length+= log_parts->length;
log_parts++;
}
}
*log_parts_count= (log_parts - start_log_parts);
DBUG_RETURN(row_length);
}
/*
Fill array with pointers to field parts to be stored in log for update
SYNOPSIS
fill_update_undo_parts()
info Maria handler
oldrec Original row
newrec New row
log_parts Store pointers to changed memory areas here
log_parts_count See RETURN
IMPLEMENTATION
Format of undo record:
Fields are stored in same order as the field array.
Number of changed fields (packed)
For each changed field
Fieldnumber (packed)
Length, if variable length field (packed)
For each changed field
Data
Packing is using ma_store_integer()
The reason we store field numbers & length separated from data (ie, not
after each other) is to get better cpu caching when we loop over
fields (as we probably don't have to access data for each field when we
want to read and old row through the undo log record).
As a special case, we use '255' for the field number of the null bitmap.
RETURN
length of data in log_parts.
log_parts_count contains number of used log_parts
*/
static size_t fill_update_undo_parts(MARIA_HA *info, const byte *oldrec,
const byte *newrec,
LEX_STRING *log_parts,
uint *log_parts_count)
{
MARIA_SHARE *share= info->s;
MARIA_COLUMNDEF *column, *end_column;
MARIA_ROW *old_row= &info->cur_row, *new_row= &info->new_row;
uchar *field_data, *start_field_data;
uchar *old_field_lengths= old_row->field_lengths;
uchar *new_field_lengths= new_row->field_lengths;
size_t row_length= 0;
uint field_count= 0;
LEX_STRING *start_log_parts;
my_bool new_column_is_empty;
DBUG_ENTER("fill_update_undo_parts");
start_log_parts= log_parts;
/*
First log part is for number of fields, field numbers and lengths
The +4 is to reserve place for the number of changed fields.
*/
start_field_data= field_data= info->update_field_data + 4;
log_parts++;
if (memcmp(oldrec, newrec, share->base.null_bytes))
{
/* Store changed null bits */
*field_data++= (uchar) 255; /* Special case */
field_count++;
log_parts->str= (char*) oldrec;
log_parts->length= share->base.null_bytes;
row_length= log_parts->length;
log_parts++;
}
/* Handle constant length fields */
for (column= share->columndef,
end_column= column+ share->base.fixed_not_null_fields;
column < end_column;
column++)
{
if (memcmp(oldrec + column->offset, newrec + column->offset,
column->length))
{
field_data= ma_store_length(field_data,
(uint) (column - share->columndef));
field_count++;
log_parts->str= (char*) oldrec + column->offset;
log_parts->length= column->length;
row_length+= log_parts->length;
log_parts++;
}
}
/* Handle the rest: NULL fields and CHAR/VARCHAR fields and BLOB's */
for (end_column= share->columndef + share->base.fields;
column < end_column;
column++)
{
const uchar *new_column_pos, *old_column_pos;
size_t new_column_length, old_column_length;
/* First check if old column is null or empty */
if (oldrec[column->null_pos] & column->null_bit)
{
/*
It's safe to skip this one as either the new column is also null
(no change) or the new_column is not null, in which case the null-bit
maps differed and we have already stored the null bitmap.
*/
continue;
}
if (old_row->empty_bits[column->empty_pos] & column->empty_bit)
{
if (new_row->empty_bits[column->empty_pos] & column->empty_bit)
continue; /* Both are empty; skip */
/* Store null length column */
field_data= ma_store_length(field_data,
(uint) (column - share->columndef));
field_data= ma_store_length(field_data, 0);
field_count++;
continue;
}
/*
Remember if the 'new' value is empty (as in this case we must always
log the original value
*/
new_column_is_empty= ((newrec[column->null_pos] & column->null_bit) ||
(new_row->empty_bits[column->empty_pos] &
column->empty_bit));
old_column_pos= oldrec + column->offset;
new_column_pos= newrec + column->offset;
old_column_length= new_column_length= column->length;
switch ((enum en_fieldtype) column->type) {
case FIELD_CHECK:
case FIELD_NORMAL: /* Fixed length field */
case FIELD_ZERO:
case FIELD_SKIP_PRESPACE: /* Not packed */
case FIELD_SKIP_ZERO: /* Fixed length field */
break;
case FIELD_VARCHAR:
new_column_length--; /* Skip length prefix */
/* Fall through */
case FIELD_SKIP_ENDSPACE: /* CHAR */
{
if (new_column_length <= 255)
{
old_column_length= *old_field_lengths++;
if (!new_column_is_empty)
new_column_length= *new_field_lengths++;
}
else
{
old_column_length= uint2korr(old_field_lengths);
old_field_lengths+= 2;
if (!new_column_is_empty)
{
new_column_length= uint2korr(new_field_lengths);
new_field_lengths+= 2;
}
}
break;
}
case FIELD_BLOB:
{
uint size_length= column->length - portable_sizeof_char_ptr;
old_column_length= _ma_calc_blob_length(size_length, old_column_pos);
memcpy_fixed((byte*) &old_column_pos,
oldrec + column->offset + size_length,
sizeof(old_column_pos));
if (!new_column_is_empty)
{
new_column_length= _ma_calc_blob_length(size_length, new_column_pos);
memcpy_fixed((byte*) &new_column_pos,
newrec + column->offset + size_length,
sizeof(old_column_pos));
}
break;
}
default:
DBUG_ASSERT(0);
}
if (new_column_is_empty || new_column_length != old_column_length ||
memcmp(old_column_pos, new_column_pos, new_column_length))
{
field_data= ma_store_length(field_data,
(uint) (column - share->columndef));
field_data= ma_store_length(field_data, old_column_length);
field_count++;
log_parts->str= (char*) old_column_pos;
log_parts->length= old_column_length;
row_length+= log_parts->length;
log_parts++;
}
}
*log_parts_count= (log_parts - start_log_parts);
/* Store number of fields before the field/field_lengths */
start_log_parts->str= ((char*)
(start_field_data -
ma_calc_length_for_store_length(field_count)));
ma_store_length(start_log_parts->str, field_count);
start_log_parts->length= (size_t) ((char*) field_data -
start_log_parts->str);
row_length+= start_log_parts->length;
DBUG_RETURN(row_length);
}
/***************************************************************************
Applying of REDO log records
***************************************************************************/
/*
Apply LOGREC_REDO_INSERT_ROW_HEAD & LOGREC_REDO_INSERT_ROW_TAIL
SYNOPSIS
_ma_apply_redo_insert_row_head_or_tail()
info Maria handler
lsn LSN to put on page
page_type HEAD_PAGE or TAIL_PAGE
header Header (without FILEID)
data Data to be put on page
data_length Length of data
RETURN
0 ok
# Error number
*/
uint _ma_apply_redo_insert_row_head_or_tail(MARIA_HA *info, LSN lsn,
uint page_type,
const byte *header,
const byte *data,
size_t data_length)
{
MARIA_SHARE *share= info->s;
ulonglong page;
uint rownr, empty_space;
uint block_size= share->block_size;
uint rec_offset;
byte *buff= info->keyread_buff, *dir;
DBUG_ENTER("_ma_apply_redo_insert_row_head_or_tail");
info->keyread_buff_used= 1;
page= page_korr(header);
rownr= dirpos_korr(header+PAGE_STORE_SIZE);
if (((page + 1) * info->s->block_size) > info->state->data_file_length)
{
/*
New page at end of file. Note that the test above is also positive if
data_file_length is not a multiple of block_size (system crashed while
writing the last page): in this case we just extend the last page and
fill it entirely with zeroes, then the REDO will put correct data on
it.
*/
DBUG_ASSERT(rownr == 0);
if (rownr != 0)
goto err;
make_empty_page(buff, block_size, page_type);
empty_space= (block_size - PAGE_OVERHEAD_SIZE);
rec_offset= PAGE_HEADER_SIZE;
dir= buff+ block_size - PAGE_SUFFIX_SIZE - DIR_ENTRY_SIZE;
/* Update that file is extended */
info->state->data_file_length= (page + 1) * info->s->block_size;
}
else
{
uint max_entry;
if (!(buff= pagecache_read(share->pagecache,
&info->dfile,
page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(my_errno);
if (lsn_korr(buff) >= lsn)
{
/* Already applied */
/* Fix bitmap, just in case */
empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
if (_ma_bitmap_set(info, page, page_type == HEAD_PAGE, empty_space))
DBUG_RETURN(my_errno);
DBUG_RETURN(0);
}
max_entry= (uint) ((uchar*) buff)[DIR_COUNT_OFFSET];
if (((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) != page_type))
{
/*
This is a page that has been freed before and now should be
changed to new type.
*/
if ((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) != BLOB_PAGE &&
(buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) != UNALLOCATED_PAGE)
goto err;
make_empty_page(buff, block_size, page_type);
empty_space= (block_size - PAGE_OVERHEAD_SIZE);
rec_offset= PAGE_HEADER_SIZE;
dir= buff+ block_size - PAGE_SUFFIX_SIZE - DIR_ENTRY_SIZE;
}
else
{
dir= (buff + block_size - DIR_ENTRY_SIZE * (rownr + 1) -
PAGE_SUFFIX_SIZE);
empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
if (max_entry >= rownr)
{
/* Add directory entry first in directory and data last on page */
DBUG_ASSERT(max_entry == rownr);
if (max_entry != rownr)
goto err;
rec_offset= (uint2korr(dir + DIR_ENTRY_SIZE) +
uint2korr(dir + DIR_ENTRY_SIZE +2));
if ((uint) (dir - buff) < rec_offset + data_length)
{
/* Create place for directory & data */
compact_page(buff, block_size, max_entry - 1, 0);
rec_offset= (uint2korr(dir + DIR_ENTRY_SIZE) +
uint2korr(dir + DIR_ENTRY_SIZE +2));
empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
DBUG_ASSERT(!((uint) (dir - buff) < rec_offset + data_length));
if ((uint) (dir - buff) < rec_offset + data_length)
goto err;
}
buff[DIR_COUNT_OFFSET]= (byte) (uchar) max_entry+1;
int2store(dir, rec_offset);
empty_space-= DIR_ENTRY_SIZE;
}
else
{
/* reuse old empty entry */
byte *pos, *end, *end_data;
DBUG_ASSERT(uint2korr(dir) == 0);
if (uint2korr(dir))
goto err; /* Should have been empty */
/* Find start of where we can put data */
end= (buff + block_size - DIR_ENTRY_SIZE * max_entry -
PAGE_SUFFIX_SIZE);
for (pos= dir ; pos >= end ; pos-= DIR_ENTRY_SIZE)
{
if ((rec_offset= uint2korr(pos)))
{
rec_offset+= uint2korr(pos+2);
break;
}
}
DBUG_ASSERT(pos >= end);
if (pos < end) /* Wrong directory */
goto err;
/* find end data */
end_data= end; /* Start of directory */
end= (buff + block_size - PAGE_SUFFIX_SIZE);
for (pos= dir ; pos < end ; pos+= DIR_ENTRY_SIZE)
{
uint offset;
if ((offset= uint2korr(pos)))
{
end_data= buff + offset;
break;
}
}
if ((uint) (end_data - (buff + rec_offset)) < data_length)
{
uint length;
/* Not enough continues space, compact page to get more */
int2store(dir, rec_offset);
compact_page(buff, block_size, rownr, 1);
rec_offset= uint2korr(dir);
length= uint2korr(dir+2);
DBUG_ASSERT(length >= data_length);
if (length < data_length)
goto err;
empty_space= length;
}
}
}
}
/* Copy data */
int2store(dir+2, data_length);
memcpy(buff + rec_offset, data, data_length);
empty_space-= data_length;
int2store(buff + EMPTY_SPACE_OFFSET, empty_space);
/* Write modified page */
lsn_store(buff, lsn);
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED,
PAGECACHE_PIN_LEFT_UNPINNED,
PAGECACHE_WRITE_DELAY, 0))
DBUG_RETURN(my_errno);
/* Fix bitmap */
if (_ma_bitmap_set(info, page, page_type == HEAD_PAGE, empty_space))
DBUG_RETURN(my_errno);
DBUG_RETURN(0);
err:
DBUG_RETURN(HA_ERR_WRONG_IN_RECORD);
}
/*
Apply LOGREC_REDO_PURGE_ROW_HEAD & LOGREC_REDO_PURGE_ROW_TAIL
SYNOPSIS
_ma_apply_redo_purge_row_head_or_tail()
info Maria handler
lsn LSN to put on page
page_type HEAD_PAGE or TAIL_PAGE
header Header (without FILEID)
NOTES
This function is very similar to delete_head_or_tail()
RETURN
0 ok
# Error number
*/
uint _ma_apply_redo_purge_row_head_or_tail(MARIA_HA *info, LSN lsn,
uint page_type,
const byte *header)
{
MARIA_SHARE *share= info->s;
ulonglong page;
uint record_number, empty_space;
uint block_size= share->block_size;
byte *buff= info->keyread_buff;
DBUG_ENTER("_ma_apply_redo_purge_row_head_or_tail");
info->keyread_buff_used= 1;
page= page_korr(header);
record_number= dirpos_korr(header+PAGE_STORE_SIZE);
if (!(buff= pagecache_read(share->pagecache,
&info->dfile,
page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(my_errno);
DBUG_ASSERT((buff[PAGE_TYPE_OFFSET] & PAGE_TYPE_MASK) == (byte) page_type);
if (lsn_korr(buff) >= lsn)
{
/* Already applied */
empty_space= uint2korr(buff + EMPTY_SPACE_OFFSET);
if (_ma_bitmap_set(info, page, page_type == HEAD_PAGE, empty_space))
DBUG_RETURN(my_errno);
DBUG_RETURN(0);
}
if (delete_dir_entry(buff, block_size, record_number, &empty_space) < 0)
DBUG_RETURN(HA_ERR_WRONG_IN_RECORD);
lsn_store(buff, lsn);
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED,
PAGECACHE_PIN_LEFT_UNPINNED,
PAGECACHE_WRITE_DELAY, 0))
DBUG_RETURN(my_errno);
/* This will work even if the page was marked as UNALLOCATED_PAGE */
if (_ma_bitmap_set(info, page, page_type == HEAD_PAGE, empty_space))
DBUG_RETURN(my_errno);
DBUG_RETURN(0);
}
/**
@brief Apply LOGREC_REDO_PURGE_BLOCKS
@param info Maria handler
@param header Header (without FILEID)
@note It marks the page free in the bitmap, and sets the directory's count
to 0.
@return Operation status
@retval 0 OK
@retval !=0 Error
*/
uint _ma_apply_redo_purge_blocks(MARIA_HA *info,
LSN lsn, const byte *header)
{
MARIA_SHARE *share= info->s;
ulonglong page;
uint page_range;
uint res;
byte *buff= info->keyread_buff;
uint block_size= share->block_size;
DBUG_ENTER("_ma_apply_redo_purge_blocks");
info->keyread_buff_used= 1;
page_range= pagerange_korr(header);
/* works only for a one-page range for now */
DBUG_ASSERT(page_range == 1); // for now
header+= PAGERANGE_STORE_SIZE;
page= page_korr(header);
header+= PAGE_STORE_SIZE;
page_range= pagerange_korr(header);
DBUG_ASSERT(page_range == 1); // for now
if (!(buff= pagecache_read(share->pagecache,
&info->dfile,
page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED, 0)))
DBUG_RETURN(my_errno);
if (lsn_korr(buff) >= lsn)
{
/* Already applied */
goto mark_free_in_bitmap;
}
buff[PAGE_TYPE_OFFSET]= UNALLOCATED_PAGE;
/*
Strictly speaking, we don't need to zero the last directory entry of this
page; setting the directory's count to zero is enough (it makes the last
directory entry invisible, irrelevant).
But as the "runtime" code (delete_head_or_tail()) called
delete_dir_entry() which zeroed the entry, if we don't do it here, we get
a difference between runtime and log-applying. Irrelevant, but it's
time-consuming to differentiate irrelevant differences from relevant
ones. So we remove the difference by zeroing the entry.
*/
{
uint rownr= ((uint) ((uchar *) buff)[DIR_COUNT_OFFSET]) - 1;
byte *dir= (buff + block_size - DIR_ENTRY_SIZE * rownr -
DIR_ENTRY_SIZE - PAGE_SUFFIX_SIZE);
dir[0]= dir[1]= 0; /* Delete entry */
}
buff[DIR_COUNT_OFFSET]= 0;
lsn_store(buff, lsn);
if (pagecache_write(share->pagecache,
&info->dfile, page, 0,
buff, PAGECACHE_PLAIN_PAGE,
PAGECACHE_LOCK_LEFT_UNLOCKED,
PAGECACHE_PIN_LEFT_UNPINNED,
PAGECACHE_WRITE_DELAY, 0))
DBUG_RETURN(my_errno);
mark_free_in_bitmap:
/** @todo leave bitmap lock to the bitmap code... */
pthread_mutex_lock(&share->bitmap.bitmap_lock);
res= _ma_reset_full_page_bits(info, &share->bitmap, page, 1);
pthread_mutex_unlock(&share->bitmap.bitmap_lock);
DBUG_RETURN(res);
}
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