linux/fs/xfs/xfs_trans.c
Christoph Hellwig 7a249cf83d xfs: fix filesystsem freeze race in xfs_trans_alloc
As pointed out by Jan xfs_trans_alloc can race with a concurrent filesystem
freeze when it sleeps during the memory allocation.  Fix this by moving the
wait_for_freeze call after the memory allocation.  This means moving the
freeze into the low-level _xfs_trans_alloc helper, which thus grows a new
argument.  Also fix up some comments in that area while at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2011-07-08 14:34:42 +02:00

2001 lines
57 KiB
C

/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* Copyright (C) 2010 Red Hat, Inc.
* All Rights Reserved.
*
* 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.
*
* This program is distributed in the hope that it would 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 the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_error.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_quota.h"
#include "xfs_trans_priv.h"
#include "xfs_trans_space.h"
#include "xfs_inode_item.h"
#include "xfs_trace.h"
kmem_zone_t *xfs_trans_zone;
kmem_zone_t *xfs_log_item_desc_zone;
/*
* Various log reservation values.
*
* These are based on the size of the file system block because that is what
* most transactions manipulate. Each adds in an additional 128 bytes per
* item logged to try to account for the overhead of the transaction mechanism.
*
* Note: Most of the reservations underestimate the number of allocation
* groups into which they could free extents in the xfs_bmap_finish() call.
* This is because the number in the worst case is quite high and quite
* unusual. In order to fix this we need to change xfs_bmap_finish() to free
* extents in only a single AG at a time. This will require changes to the
* EFI code as well, however, so that the EFI for the extents not freed is
* logged again in each transaction. See SGI PV #261917.
*
* Reservation functions here avoid a huge stack in xfs_trans_init due to
* register overflow from temporaries in the calculations.
*/
/*
* In a write transaction we can allocate a maximum of 2
* extents. This gives:
* the inode getting the new extents: inode size
* the inode's bmap btree: max depth * block size
* the agfs of the ags from which the extents are allocated: 2 * sector
* the superblock free block counter: sector size
* the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
* And the bmap_finish transaction can free bmap blocks in a join:
* the agfs of the ags containing the blocks: 2 * sector size
* the agfls of the ags containing the blocks: 2 * sector size
* the super block free block counter: sector size
* the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_write_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
XFS_FSB_TO_B(mp, XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)) +
2 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 2) +
128 * (4 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) +
XFS_ALLOCFREE_LOG_COUNT(mp, 2))),
(2 * mp->m_sb.sb_sectsize +
2 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 2) +
128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))));
}
/*
* In truncating a file we free up to two extents at once. We can modify:
* the inode being truncated: inode size
* the inode's bmap btree: (max depth + 1) * block size
* And the bmap_finish transaction can free the blocks and bmap blocks:
* the agf for each of the ags: 4 * sector size
* the agfl for each of the ags: 4 * sector size
* the super block to reflect the freed blocks: sector size
* worst case split in allocation btrees per extent assuming 4 extents:
* 4 exts * 2 trees * (2 * max depth - 1) * block size
* the inode btree: max depth * blocksize
* the allocation btrees: 2 trees * (max depth - 1) * block size
*/
STATIC uint
xfs_calc_itruncate_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
XFS_FSB_TO_B(mp, XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1) +
128 * (2 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK))),
(4 * mp->m_sb.sb_sectsize +
4 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 4) +
128 * (9 + XFS_ALLOCFREE_LOG_COUNT(mp, 4)) +
128 * 5 +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (2 + XFS_IALLOC_BLOCKS(mp) + mp->m_in_maxlevels +
XFS_ALLOCFREE_LOG_COUNT(mp, 1))));
}
/*
* In renaming a files we can modify:
* the four inodes involved: 4 * inode size
* the two directory btrees: 2 * (max depth + v2) * dir block size
* the two directory bmap btrees: 2 * max depth * block size
* And the bmap_finish transaction can free dir and bmap blocks (two sets
* of bmap blocks) giving:
* the agf for the ags in which the blocks live: 3 * sector size
* the agfl for the ags in which the blocks live: 3 * sector size
* the superblock for the free block count: sector size
* the allocation btrees: 3 exts * 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_rename_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((4 * mp->m_sb.sb_inodesize +
2 * XFS_DIROP_LOG_RES(mp) +
128 * (4 + 2 * XFS_DIROP_LOG_COUNT(mp))),
(3 * mp->m_sb.sb_sectsize +
3 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 3) +
128 * (7 + XFS_ALLOCFREE_LOG_COUNT(mp, 3))));
}
/*
* For creating a link to an inode:
* the parent directory inode: inode size
* the linked inode: inode size
* the directory btree could split: (max depth + v2) * dir block size
* the directory bmap btree could join or split: (max depth + v2) * blocksize
* And the bmap_finish transaction can free some bmap blocks giving:
* the agf for the ag in which the blocks live: sector size
* the agfl for the ag in which the blocks live: sector size
* the superblock for the free block count: sector size
* the allocation btrees: 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_link_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
mp->m_sb.sb_inodesize +
XFS_DIROP_LOG_RES(mp) +
128 * (2 + XFS_DIROP_LOG_COUNT(mp))),
(mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (3 + XFS_ALLOCFREE_LOG_COUNT(mp, 1))));
}
/*
* For removing a directory entry we can modify:
* the parent directory inode: inode size
* the removed inode: inode size
* the directory btree could join: (max depth + v2) * dir block size
* the directory bmap btree could join or split: (max depth + v2) * blocksize
* And the bmap_finish transaction can free the dir and bmap blocks giving:
* the agf for the ag in which the blocks live: 2 * sector size
* the agfl for the ag in which the blocks live: 2 * sector size
* the superblock for the free block count: sector size
* the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_remove_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
mp->m_sb.sb_inodesize +
XFS_DIROP_LOG_RES(mp) +
128 * (2 + XFS_DIROP_LOG_COUNT(mp))),
(2 * mp->m_sb.sb_sectsize +
2 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 2) +
128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))));
}
/*
* For symlink we can modify:
* the parent directory inode: inode size
* the new inode: inode size
* the inode btree entry: 1 block
* the directory btree: (max depth + v2) * dir block size
* the directory inode's bmap btree: (max depth + v2) * block size
* the blocks for the symlink: 1 kB
* Or in the first xact we allocate some inodes giving:
* the agi and agf of the ag getting the new inodes: 2 * sectorsize
* the inode blocks allocated: XFS_IALLOC_BLOCKS * blocksize
* the inode btree: max depth * blocksize
* the allocation btrees: 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_symlink_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
mp->m_sb.sb_inodesize +
XFS_FSB_TO_B(mp, 1) +
XFS_DIROP_LOG_RES(mp) +
1024 +
128 * (4 + XFS_DIROP_LOG_COUNT(mp))),
(2 * mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, XFS_IALLOC_BLOCKS(mp)) +
XFS_FSB_TO_B(mp, mp->m_in_maxlevels) +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (2 + XFS_IALLOC_BLOCKS(mp) + mp->m_in_maxlevels +
XFS_ALLOCFREE_LOG_COUNT(mp, 1))));
}
/*
* For create we can modify:
* the parent directory inode: inode size
* the new inode: inode size
* the inode btree entry: block size
* the superblock for the nlink flag: sector size
* the directory btree: (max depth + v2) * dir block size
* the directory inode's bmap btree: (max depth + v2) * block size
* Or in the first xact we allocate some inodes giving:
* the agi and agf of the ag getting the new inodes: 2 * sectorsize
* the superblock for the nlink flag: sector size
* the inode blocks allocated: XFS_IALLOC_BLOCKS * blocksize
* the inode btree: max depth * blocksize
* the allocation btrees: 2 trees * (max depth - 1) * block size
*/
STATIC uint
xfs_calc_create_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
mp->m_sb.sb_inodesize +
mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, 1) +
XFS_DIROP_LOG_RES(mp) +
128 * (3 + XFS_DIROP_LOG_COUNT(mp))),
(3 * mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, XFS_IALLOC_BLOCKS(mp)) +
XFS_FSB_TO_B(mp, mp->m_in_maxlevels) +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (2 + XFS_IALLOC_BLOCKS(mp) + mp->m_in_maxlevels +
XFS_ALLOCFREE_LOG_COUNT(mp, 1))));
}
/*
* Making a new directory is the same as creating a new file.
*/
STATIC uint
xfs_calc_mkdir_reservation(
struct xfs_mount *mp)
{
return xfs_calc_create_reservation(mp);
}
/*
* In freeing an inode we can modify:
* the inode being freed: inode size
* the super block free inode counter: sector size
* the agi hash list and counters: sector size
* the inode btree entry: block size
* the on disk inode before ours in the agi hash list: inode cluster size
* the inode btree: max depth * blocksize
* the allocation btrees: 2 trees * (max depth - 1) * block size
*/
STATIC uint
xfs_calc_ifree_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
mp->m_sb.sb_inodesize +
mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, 1) +
MAX((__uint16_t)XFS_FSB_TO_B(mp, 1),
XFS_INODE_CLUSTER_SIZE(mp)) +
128 * 5 +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (2 + XFS_IALLOC_BLOCKS(mp) + mp->m_in_maxlevels +
XFS_ALLOCFREE_LOG_COUNT(mp, 1));
}
/*
* When only changing the inode we log the inode and possibly the superblock
* We also add a bit of slop for the transaction stuff.
*/
STATIC uint
xfs_calc_ichange_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
mp->m_sb.sb_inodesize +
mp->m_sb.sb_sectsize +
512;
}
/*
* Growing the data section of the filesystem.
* superblock
* agi and agf
* allocation btrees
*/
STATIC uint
xfs_calc_growdata_reservation(
struct xfs_mount *mp)
{
return mp->m_sb.sb_sectsize * 3 +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (3 + XFS_ALLOCFREE_LOG_COUNT(mp, 1));
}
/*
* Growing the rt section of the filesystem.
* In the first set of transactions (ALLOC) we allocate space to the
* bitmap or summary files.
* superblock: sector size
* agf of the ag from which the extent is allocated: sector size
* bmap btree for bitmap/summary inode: max depth * blocksize
* bitmap/summary inode: inode size
* allocation btrees for 1 block alloc: 2 * (2 * maxdepth - 1) * blocksize
*/
STATIC uint
xfs_calc_growrtalloc_reservation(
struct xfs_mount *mp)
{
return 2 * mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK)) +
mp->m_sb.sb_inodesize +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (3 + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) +
XFS_ALLOCFREE_LOG_COUNT(mp, 1));
}
/*
* Growing the rt section of the filesystem.
* In the second set of transactions (ZERO) we zero the new metadata blocks.
* one bitmap/summary block: blocksize
*/
STATIC uint
xfs_calc_growrtzero_reservation(
struct xfs_mount *mp)
{
return mp->m_sb.sb_blocksize + 128;
}
/*
* Growing the rt section of the filesystem.
* In the third set of transactions (FREE) we update metadata without
* allocating any new blocks.
* superblock: sector size
* bitmap inode: inode size
* summary inode: inode size
* one bitmap block: blocksize
* summary blocks: new summary size
*/
STATIC uint
xfs_calc_growrtfree_reservation(
struct xfs_mount *mp)
{
return mp->m_sb.sb_sectsize +
2 * mp->m_sb.sb_inodesize +
mp->m_sb.sb_blocksize +
mp->m_rsumsize +
128 * 5;
}
/*
* Logging the inode modification timestamp on a synchronous write.
* inode
*/
STATIC uint
xfs_calc_swrite_reservation(
struct xfs_mount *mp)
{
return mp->m_sb.sb_inodesize + 128;
}
/*
* Logging the inode mode bits when writing a setuid/setgid file
* inode
*/
STATIC uint
xfs_calc_writeid_reservation(xfs_mount_t *mp)
{
return mp->m_sb.sb_inodesize + 128;
}
/*
* Converting the inode from non-attributed to attributed.
* the inode being converted: inode size
* agf block and superblock (for block allocation)
* the new block (directory sized)
* bmap blocks for the new directory block
* allocation btrees
*/
STATIC uint
xfs_calc_addafork_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
mp->m_sb.sb_inodesize +
mp->m_sb.sb_sectsize * 2 +
mp->m_dirblksize +
XFS_FSB_TO_B(mp, XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1) +
XFS_ALLOCFREE_LOG_RES(mp, 1) +
128 * (4 + XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1 +
XFS_ALLOCFREE_LOG_COUNT(mp, 1));
}
/*
* Removing the attribute fork of a file
* the inode being truncated: inode size
* the inode's bmap btree: max depth * block size
* And the bmap_finish transaction can free the blocks and bmap blocks:
* the agf for each of the ags: 4 * sector size
* the agfl for each of the ags: 4 * sector size
* the super block to reflect the freed blocks: sector size
* worst case split in allocation btrees per extent assuming 4 extents:
* 4 exts * 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_attrinval_reservation(
struct xfs_mount *mp)
{
return MAX((mp->m_sb.sb_inodesize +
XFS_FSB_TO_B(mp, XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) +
128 * (1 + XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK))),
(4 * mp->m_sb.sb_sectsize +
4 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 4) +
128 * (9 + XFS_ALLOCFREE_LOG_COUNT(mp, 4))));
}
/*
* Setting an attribute.
* the inode getting the attribute
* the superblock for allocations
* the agfs extents are allocated from
* the attribute btree * max depth
* the inode allocation btree
* Since attribute transaction space is dependent on the size of the attribute,
* the calculation is done partially at mount time and partially at runtime.
*/
STATIC uint
xfs_calc_attrset_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
mp->m_sb.sb_inodesize +
mp->m_sb.sb_sectsize +
XFS_FSB_TO_B(mp, XFS_DA_NODE_MAXDEPTH) +
128 * (2 + XFS_DA_NODE_MAXDEPTH);
}
/*
* Removing an attribute.
* the inode: inode size
* the attribute btree could join: max depth * block size
* the inode bmap btree could join or split: max depth * block size
* And the bmap_finish transaction can free the attr blocks freed giving:
* the agf for the ag in which the blocks live: 2 * sector size
* the agfl for the ag in which the blocks live: 2 * sector size
* the superblock for the free block count: sector size
* the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
*/
STATIC uint
xfs_calc_attrrm_reservation(
struct xfs_mount *mp)
{
return XFS_DQUOT_LOGRES(mp) +
MAX((mp->m_sb.sb_inodesize +
XFS_FSB_TO_B(mp, XFS_DA_NODE_MAXDEPTH) +
XFS_FSB_TO_B(mp, XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) +
128 * (1 + XFS_DA_NODE_MAXDEPTH +
XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK))),
(2 * mp->m_sb.sb_sectsize +
2 * mp->m_sb.sb_sectsize +
mp->m_sb.sb_sectsize +
XFS_ALLOCFREE_LOG_RES(mp, 2) +
128 * (5 + XFS_ALLOCFREE_LOG_COUNT(mp, 2))));
}
/*
* Clearing a bad agino number in an agi hash bucket.
*/
STATIC uint
xfs_calc_clear_agi_bucket_reservation(
struct xfs_mount *mp)
{
return mp->m_sb.sb_sectsize + 128;
}
/*
* Initialize the precomputed transaction reservation values
* in the mount structure.
*/
void
xfs_trans_init(
struct xfs_mount *mp)
{
struct xfs_trans_reservations *resp = &mp->m_reservations;
resp->tr_write = xfs_calc_write_reservation(mp);
resp->tr_itruncate = xfs_calc_itruncate_reservation(mp);
resp->tr_rename = xfs_calc_rename_reservation(mp);
resp->tr_link = xfs_calc_link_reservation(mp);
resp->tr_remove = xfs_calc_remove_reservation(mp);
resp->tr_symlink = xfs_calc_symlink_reservation(mp);
resp->tr_create = xfs_calc_create_reservation(mp);
resp->tr_mkdir = xfs_calc_mkdir_reservation(mp);
resp->tr_ifree = xfs_calc_ifree_reservation(mp);
resp->tr_ichange = xfs_calc_ichange_reservation(mp);
resp->tr_growdata = xfs_calc_growdata_reservation(mp);
resp->tr_swrite = xfs_calc_swrite_reservation(mp);
resp->tr_writeid = xfs_calc_writeid_reservation(mp);
resp->tr_addafork = xfs_calc_addafork_reservation(mp);
resp->tr_attrinval = xfs_calc_attrinval_reservation(mp);
resp->tr_attrset = xfs_calc_attrset_reservation(mp);
resp->tr_attrrm = xfs_calc_attrrm_reservation(mp);
resp->tr_clearagi = xfs_calc_clear_agi_bucket_reservation(mp);
resp->tr_growrtalloc = xfs_calc_growrtalloc_reservation(mp);
resp->tr_growrtzero = xfs_calc_growrtzero_reservation(mp);
resp->tr_growrtfree = xfs_calc_growrtfree_reservation(mp);
}
/*
* This routine is called to allocate a transaction structure.
*
* The type parameter indicates the type of the transaction. These
* are enumerated in xfs_trans.h.
*/
struct xfs_trans *
_xfs_trans_alloc(
struct xfs_mount *mp,
uint type,
uint memflags,
bool wait_for_freeze)
{
struct xfs_trans *tp;
atomic_inc(&mp->m_active_trans);
if (wait_for_freeze)
xfs_wait_for_freeze(mp, SB_FREEZE_TRANS);
tp = kmem_zone_zalloc(xfs_trans_zone, memflags);
tp->t_magic = XFS_TRANS_MAGIC;
tp->t_type = type;
tp->t_mountp = mp;
INIT_LIST_HEAD(&tp->t_items);
INIT_LIST_HEAD(&tp->t_busy);
return tp;
}
/*
* Free the transaction structure. If there is more clean up
* to do when the structure is freed, add it here.
*/
STATIC void
xfs_trans_free(
struct xfs_trans *tp)
{
xfs_alloc_busy_sort(&tp->t_busy);
xfs_alloc_busy_clear(tp->t_mountp, &tp->t_busy, false);
atomic_dec(&tp->t_mountp->m_active_trans);
xfs_trans_free_dqinfo(tp);
kmem_zone_free(xfs_trans_zone, tp);
}
/*
* This is called to create a new transaction which will share the
* permanent log reservation of the given transaction. The remaining
* unused block and rt extent reservations are also inherited. This
* implies that the original transaction is no longer allowed to allocate
* blocks. Locks and log items, however, are no inherited. They must
* be added to the new transaction explicitly.
*/
xfs_trans_t *
xfs_trans_dup(
xfs_trans_t *tp)
{
xfs_trans_t *ntp;
ntp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP);
/*
* Initialize the new transaction structure.
*/
ntp->t_magic = XFS_TRANS_MAGIC;
ntp->t_type = tp->t_type;
ntp->t_mountp = tp->t_mountp;
INIT_LIST_HEAD(&ntp->t_items);
INIT_LIST_HEAD(&ntp->t_busy);
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(tp->t_ticket != NULL);
ntp->t_flags = XFS_TRANS_PERM_LOG_RES | (tp->t_flags & XFS_TRANS_RESERVE);
ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
tp->t_blk_res = tp->t_blk_res_used;
ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
tp->t_rtx_res = tp->t_rtx_res_used;
ntp->t_pflags = tp->t_pflags;
xfs_trans_dup_dqinfo(tp, ntp);
atomic_inc(&tp->t_mountp->m_active_trans);
return ntp;
}
/*
* This is called to reserve free disk blocks and log space for the
* given transaction. This must be done before allocating any resources
* within the transaction.
*
* This will return ENOSPC if there are not enough blocks available.
* It will sleep waiting for available log space.
* The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
* is used by long running transactions. If any one of the reservations
* fails then they will all be backed out.
*
* This does not do quota reservations. That typically is done by the
* caller afterwards.
*/
int
xfs_trans_reserve(
xfs_trans_t *tp,
uint blocks,
uint logspace,
uint rtextents,
uint flags,
uint logcount)
{
int log_flags;
int error = 0;
int rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
/* Mark this thread as being in a transaction */
current_set_flags_nested(&tp->t_pflags, PF_FSTRANS);
/*
* Attempt to reserve the needed disk blocks by decrementing
* the number needed from the number available. This will
* fail if the count would go below zero.
*/
if (blocks > 0) {
error = xfs_icsb_modify_counters(tp->t_mountp, XFS_SBS_FDBLOCKS,
-((int64_t)blocks), rsvd);
if (error != 0) {
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
return (XFS_ERROR(ENOSPC));
}
tp->t_blk_res += blocks;
}
/*
* Reserve the log space needed for this transaction.
*/
if (logspace > 0) {
ASSERT((tp->t_log_res == 0) || (tp->t_log_res == logspace));
ASSERT((tp->t_log_count == 0) ||
(tp->t_log_count == logcount));
if (flags & XFS_TRANS_PERM_LOG_RES) {
log_flags = XFS_LOG_PERM_RESERV;
tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
} else {
ASSERT(tp->t_ticket == NULL);
ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
log_flags = 0;
}
error = xfs_log_reserve(tp->t_mountp, logspace, logcount,
&tp->t_ticket,
XFS_TRANSACTION, log_flags, tp->t_type);
if (error) {
goto undo_blocks;
}
tp->t_log_res = logspace;
tp->t_log_count = logcount;
}
/*
* Attempt to reserve the needed realtime extents by decrementing
* the number needed from the number available. This will
* fail if the count would go below zero.
*/
if (rtextents > 0) {
error = xfs_mod_incore_sb(tp->t_mountp, XFS_SBS_FREXTENTS,
-((int64_t)rtextents), rsvd);
if (error) {
error = XFS_ERROR(ENOSPC);
goto undo_log;
}
tp->t_rtx_res += rtextents;
}
return 0;
/*
* Error cases jump to one of these labels to undo any
* reservations which have already been performed.
*/
undo_log:
if (logspace > 0) {
if (flags & XFS_TRANS_PERM_LOG_RES) {
log_flags = XFS_LOG_REL_PERM_RESERV;
} else {
log_flags = 0;
}
xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, log_flags);
tp->t_ticket = NULL;
tp->t_log_res = 0;
tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
}
undo_blocks:
if (blocks > 0) {
xfs_icsb_modify_counters(tp->t_mountp, XFS_SBS_FDBLOCKS,
(int64_t)blocks, rsvd);
tp->t_blk_res = 0;
}
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
return error;
}
/*
* Record the indicated change to the given field for application
* to the file system's superblock when the transaction commits.
* For now, just store the change in the transaction structure.
*
* Mark the transaction structure to indicate that the superblock
* needs to be updated before committing.
*
* Because we may not be keeping track of allocated/free inodes and
* used filesystem blocks in the superblock, we do not mark the
* superblock dirty in this transaction if we modify these fields.
* We still need to update the transaction deltas so that they get
* applied to the incore superblock, but we don't want them to
* cause the superblock to get locked and logged if these are the
* only fields in the superblock that the transaction modifies.
*/
void
xfs_trans_mod_sb(
xfs_trans_t *tp,
uint field,
int64_t delta)
{
uint32_t flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
xfs_mount_t *mp = tp->t_mountp;
switch (field) {
case XFS_TRANS_SB_ICOUNT:
tp->t_icount_delta += delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_IFREE:
tp->t_ifree_delta += delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_FDBLOCKS:
/*
* Track the number of blocks allocated in the
* transaction. Make sure it does not exceed the
* number reserved.
*/
if (delta < 0) {
tp->t_blk_res_used += (uint)-delta;
ASSERT(tp->t_blk_res_used <= tp->t_blk_res);
}
tp->t_fdblocks_delta += delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_RES_FDBLOCKS:
/*
* The allocation has already been applied to the
* in-core superblock's counter. This should only
* be applied to the on-disk superblock.
*/
ASSERT(delta < 0);
tp->t_res_fdblocks_delta += delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
flags &= ~XFS_TRANS_SB_DIRTY;
break;
case XFS_TRANS_SB_FREXTENTS:
/*
* Track the number of blocks allocated in the
* transaction. Make sure it does not exceed the
* number reserved.
*/
if (delta < 0) {
tp->t_rtx_res_used += (uint)-delta;
ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
}
tp->t_frextents_delta += delta;
break;
case XFS_TRANS_SB_RES_FREXTENTS:
/*
* The allocation has already been applied to the
* in-core superblock's counter. This should only
* be applied to the on-disk superblock.
*/
ASSERT(delta < 0);
tp->t_res_frextents_delta += delta;
break;
case XFS_TRANS_SB_DBLOCKS:
ASSERT(delta > 0);
tp->t_dblocks_delta += delta;
break;
case XFS_TRANS_SB_AGCOUNT:
ASSERT(delta > 0);
tp->t_agcount_delta += delta;
break;
case XFS_TRANS_SB_IMAXPCT:
tp->t_imaxpct_delta += delta;
break;
case XFS_TRANS_SB_REXTSIZE:
tp->t_rextsize_delta += delta;
break;
case XFS_TRANS_SB_RBMBLOCKS:
tp->t_rbmblocks_delta += delta;
break;
case XFS_TRANS_SB_RBLOCKS:
tp->t_rblocks_delta += delta;
break;
case XFS_TRANS_SB_REXTENTS:
tp->t_rextents_delta += delta;
break;
case XFS_TRANS_SB_REXTSLOG:
tp->t_rextslog_delta += delta;
break;
default:
ASSERT(0);
return;
}
tp->t_flags |= flags;
}
/*
* xfs_trans_apply_sb_deltas() is called from the commit code
* to bring the superblock buffer into the current transaction
* and modify it as requested by earlier calls to xfs_trans_mod_sb().
*
* For now we just look at each field allowed to change and change
* it if necessary.
*/
STATIC void
xfs_trans_apply_sb_deltas(
xfs_trans_t *tp)
{
xfs_dsb_t *sbp;
xfs_buf_t *bp;
int whole = 0;
bp = xfs_trans_getsb(tp, tp->t_mountp, 0);
sbp = XFS_BUF_TO_SBP(bp);
/*
* Check that superblock mods match the mods made to AGF counters.
*/
ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
(tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
tp->t_ag_btree_delta));
/*
* Only update the superblock counters if we are logging them
*/
if (!xfs_sb_version_haslazysbcount(&(tp->t_mountp->m_sb))) {
if (tp->t_icount_delta)
be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
if (tp->t_ifree_delta)
be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
if (tp->t_fdblocks_delta)
be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
if (tp->t_res_fdblocks_delta)
be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
}
if (tp->t_frextents_delta)
be64_add_cpu(&sbp->sb_frextents, tp->t_frextents_delta);
if (tp->t_res_frextents_delta)
be64_add_cpu(&sbp->sb_frextents, tp->t_res_frextents_delta);
if (tp->t_dblocks_delta) {
be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta);
whole = 1;
}
if (tp->t_agcount_delta) {
be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta);
whole = 1;
}
if (tp->t_imaxpct_delta) {
sbp->sb_imax_pct += tp->t_imaxpct_delta;
whole = 1;
}
if (tp->t_rextsize_delta) {
be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta);
whole = 1;
}
if (tp->t_rbmblocks_delta) {
be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta);
whole = 1;
}
if (tp->t_rblocks_delta) {
be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta);
whole = 1;
}
if (tp->t_rextents_delta) {
be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta);
whole = 1;
}
if (tp->t_rextslog_delta) {
sbp->sb_rextslog += tp->t_rextslog_delta;
whole = 1;
}
if (whole)
/*
* Log the whole thing, the fields are noncontiguous.
*/
xfs_trans_log_buf(tp, bp, 0, sizeof(xfs_dsb_t) - 1);
else
/*
* Since all the modifiable fields are contiguous, we
* can get away with this.
*/
xfs_trans_log_buf(tp, bp, offsetof(xfs_dsb_t, sb_icount),
offsetof(xfs_dsb_t, sb_frextents) +
sizeof(sbp->sb_frextents) - 1);
}
/*
* xfs_trans_unreserve_and_mod_sb() is called to release unused reservations
* and apply superblock counter changes to the in-core superblock. The
* t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT
* applied to the in-core superblock. The idea is that that has already been
* done.
*
* This is done efficiently with a single call to xfs_mod_incore_sb_batch().
* However, we have to ensure that we only modify each superblock field only
* once because the application of the delta values may not be atomic. That can
* lead to ENOSPC races occurring if we have two separate modifcations of the
* free space counter to put back the entire reservation and then take away
* what we used.
*
* If we are not logging superblock counters, then the inode allocated/free and
* used block counts are not updated in the on disk superblock. In this case,
* XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we
* still need to update the incore superblock with the changes.
*/
void
xfs_trans_unreserve_and_mod_sb(
xfs_trans_t *tp)
{
xfs_mod_sb_t msb[9]; /* If you add cases, add entries */
xfs_mod_sb_t *msbp;
xfs_mount_t *mp = tp->t_mountp;
/* REFERENCED */
int error;
int rsvd;
int64_t blkdelta = 0;
int64_t rtxdelta = 0;
int64_t idelta = 0;
int64_t ifreedelta = 0;
msbp = msb;
rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
/* calculate deltas */
if (tp->t_blk_res > 0)
blkdelta = tp->t_blk_res;
if ((tp->t_fdblocks_delta != 0) &&
(xfs_sb_version_haslazysbcount(&mp->m_sb) ||
(tp->t_flags & XFS_TRANS_SB_DIRTY)))
blkdelta += tp->t_fdblocks_delta;
if (tp->t_rtx_res > 0)
rtxdelta = tp->t_rtx_res;
if ((tp->t_frextents_delta != 0) &&
(tp->t_flags & XFS_TRANS_SB_DIRTY))
rtxdelta += tp->t_frextents_delta;
if (xfs_sb_version_haslazysbcount(&mp->m_sb) ||
(tp->t_flags & XFS_TRANS_SB_DIRTY)) {
idelta = tp->t_icount_delta;
ifreedelta = tp->t_ifree_delta;
}
/* apply the per-cpu counters */
if (blkdelta) {
error = xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS,
blkdelta, rsvd);
if (error)
goto out;
}
if (idelta) {
error = xfs_icsb_modify_counters(mp, XFS_SBS_ICOUNT,
idelta, rsvd);
if (error)
goto out_undo_fdblocks;
}
if (ifreedelta) {
error = xfs_icsb_modify_counters(mp, XFS_SBS_IFREE,
ifreedelta, rsvd);
if (error)
goto out_undo_icount;
}
/* apply remaining deltas */
if (rtxdelta != 0) {
msbp->msb_field = XFS_SBS_FREXTENTS;
msbp->msb_delta = rtxdelta;
msbp++;
}
if (tp->t_flags & XFS_TRANS_SB_DIRTY) {
if (tp->t_dblocks_delta != 0) {
msbp->msb_field = XFS_SBS_DBLOCKS;
msbp->msb_delta = tp->t_dblocks_delta;
msbp++;
}
if (tp->t_agcount_delta != 0) {
msbp->msb_field = XFS_SBS_AGCOUNT;
msbp->msb_delta = tp->t_agcount_delta;
msbp++;
}
if (tp->t_imaxpct_delta != 0) {
msbp->msb_field = XFS_SBS_IMAX_PCT;
msbp->msb_delta = tp->t_imaxpct_delta;
msbp++;
}
if (tp->t_rextsize_delta != 0) {
msbp->msb_field = XFS_SBS_REXTSIZE;
msbp->msb_delta = tp->t_rextsize_delta;
msbp++;
}
if (tp->t_rbmblocks_delta != 0) {
msbp->msb_field = XFS_SBS_RBMBLOCKS;
msbp->msb_delta = tp->t_rbmblocks_delta;
msbp++;
}
if (tp->t_rblocks_delta != 0) {
msbp->msb_field = XFS_SBS_RBLOCKS;
msbp->msb_delta = tp->t_rblocks_delta;
msbp++;
}
if (tp->t_rextents_delta != 0) {
msbp->msb_field = XFS_SBS_REXTENTS;
msbp->msb_delta = tp->t_rextents_delta;
msbp++;
}
if (tp->t_rextslog_delta != 0) {
msbp->msb_field = XFS_SBS_REXTSLOG;
msbp->msb_delta = tp->t_rextslog_delta;
msbp++;
}
}
/*
* If we need to change anything, do it.
*/
if (msbp > msb) {
error = xfs_mod_incore_sb_batch(tp->t_mountp, msb,
(uint)(msbp - msb), rsvd);
if (error)
goto out_undo_ifreecount;
}
return;
out_undo_ifreecount:
if (ifreedelta)
xfs_icsb_modify_counters(mp, XFS_SBS_IFREE, -ifreedelta, rsvd);
out_undo_icount:
if (idelta)
xfs_icsb_modify_counters(mp, XFS_SBS_ICOUNT, -idelta, rsvd);
out_undo_fdblocks:
if (blkdelta)
xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS, -blkdelta, rsvd);
out:
ASSERT(error == 0);
return;
}
/*
* Add the given log item to the transaction's list of log items.
*
* The log item will now point to its new descriptor with its li_desc field.
*/
void
xfs_trans_add_item(
struct xfs_trans *tp,
struct xfs_log_item *lip)
{
struct xfs_log_item_desc *lidp;
ASSERT(lip->li_mountp = tp->t_mountp);
ASSERT(lip->li_ailp = tp->t_mountp->m_ail);
lidp = kmem_zone_zalloc(xfs_log_item_desc_zone, KM_SLEEP | KM_NOFS);
lidp->lid_item = lip;
lidp->lid_flags = 0;
lidp->lid_size = 0;
list_add_tail(&lidp->lid_trans, &tp->t_items);
lip->li_desc = lidp;
}
STATIC void
xfs_trans_free_item_desc(
struct xfs_log_item_desc *lidp)
{
list_del_init(&lidp->lid_trans);
kmem_zone_free(xfs_log_item_desc_zone, lidp);
}
/*
* Unlink and free the given descriptor.
*/
void
xfs_trans_del_item(
struct xfs_log_item *lip)
{
xfs_trans_free_item_desc(lip->li_desc);
lip->li_desc = NULL;
}
/*
* Unlock all of the items of a transaction and free all the descriptors
* of that transaction.
*/
void
xfs_trans_free_items(
struct xfs_trans *tp,
xfs_lsn_t commit_lsn,
int flags)
{
struct xfs_log_item_desc *lidp, *next;
list_for_each_entry_safe(lidp, next, &tp->t_items, lid_trans) {
struct xfs_log_item *lip = lidp->lid_item;
lip->li_desc = NULL;
if (commit_lsn != NULLCOMMITLSN)
IOP_COMMITTING(lip, commit_lsn);
if (flags & XFS_TRANS_ABORT)
lip->li_flags |= XFS_LI_ABORTED;
IOP_UNLOCK(lip);
xfs_trans_free_item_desc(lidp);
}
}
/*
* Unlock the items associated with a transaction.
*
* Items which were not logged should be freed. Those which were logged must
* still be tracked so they can be unpinned when the transaction commits.
*/
STATIC void
xfs_trans_unlock_items(
struct xfs_trans *tp,
xfs_lsn_t commit_lsn)
{
struct xfs_log_item_desc *lidp, *next;
list_for_each_entry_safe(lidp, next, &tp->t_items, lid_trans) {
struct xfs_log_item *lip = lidp->lid_item;
lip->li_desc = NULL;
if (commit_lsn != NULLCOMMITLSN)
IOP_COMMITTING(lip, commit_lsn);
IOP_UNLOCK(lip);
/*
* Free the descriptor if the item is not dirty
* within this transaction.
*/
if (!(lidp->lid_flags & XFS_LID_DIRTY))
xfs_trans_free_item_desc(lidp);
}
}
/*
* Total up the number of log iovecs needed to commit this
* transaction. The transaction itself needs one for the
* transaction header. Ask each dirty item in turn how many
* it needs to get the total.
*/
static uint
xfs_trans_count_vecs(
struct xfs_trans *tp)
{
int nvecs;
struct xfs_log_item_desc *lidp;
nvecs = 1;
/* In the non-debug case we need to start bailing out if we
* didn't find a log_item here, return zero and let trans_commit
* deal with it.
*/
if (list_empty(&tp->t_items)) {
ASSERT(0);
return 0;
}
list_for_each_entry(lidp, &tp->t_items, lid_trans) {
/*
* Skip items which aren't dirty in this transaction.
*/
if (!(lidp->lid_flags & XFS_LID_DIRTY))
continue;
lidp->lid_size = IOP_SIZE(lidp->lid_item);
nvecs += lidp->lid_size;
}
return nvecs;
}
/*
* Fill in the vector with pointers to data to be logged
* by this transaction. The transaction header takes
* the first vector, and then each dirty item takes the
* number of vectors it indicated it needed in xfs_trans_count_vecs().
*
* As each item fills in the entries it needs, also pin the item
* so that it cannot be flushed out until the log write completes.
*/
static void
xfs_trans_fill_vecs(
struct xfs_trans *tp,
struct xfs_log_iovec *log_vector)
{
struct xfs_log_item_desc *lidp;
struct xfs_log_iovec *vecp;
uint nitems;
/*
* Skip over the entry for the transaction header, we'll
* fill that in at the end.
*/
vecp = log_vector + 1;
nitems = 0;
ASSERT(!list_empty(&tp->t_items));
list_for_each_entry(lidp, &tp->t_items, lid_trans) {
/* Skip items which aren't dirty in this transaction. */
if (!(lidp->lid_flags & XFS_LID_DIRTY))
continue;
/*
* The item may be marked dirty but not log anything. This can
* be used to get called when a transaction is committed.
*/
if (lidp->lid_size)
nitems++;
IOP_FORMAT(lidp->lid_item, vecp);
vecp += lidp->lid_size;
IOP_PIN(lidp->lid_item);
}
/*
* Now that we've counted the number of items in this transaction, fill
* in the transaction header. Note that the transaction header does not
* have a log item.
*/
tp->t_header.th_magic = XFS_TRANS_HEADER_MAGIC;
tp->t_header.th_type = tp->t_type;
tp->t_header.th_num_items = nitems;
log_vector->i_addr = (xfs_caddr_t)&tp->t_header;
log_vector->i_len = sizeof(xfs_trans_header_t);
log_vector->i_type = XLOG_REG_TYPE_TRANSHDR;
}
/*
* The committed item processing consists of calling the committed routine of
* each logged item, updating the item's position in the AIL if necessary, and
* unpinning each item. If the committed routine returns -1, then do nothing
* further with the item because it may have been freed.
*
* Since items are unlocked when they are copied to the incore log, it is
* possible for two transactions to be completing and manipulating the same
* item simultaneously. The AIL lock will protect the lsn field of each item.
* The value of this field can never go backwards.
*
* We unpin the items after repositioning them in the AIL, because otherwise
* they could be immediately flushed and we'd have to race with the flusher
* trying to pull the item from the AIL as we add it.
*/
static void
xfs_trans_item_committed(
struct xfs_log_item *lip,
xfs_lsn_t commit_lsn,
int aborted)
{
xfs_lsn_t item_lsn;
struct xfs_ail *ailp;
if (aborted)
lip->li_flags |= XFS_LI_ABORTED;
item_lsn = IOP_COMMITTED(lip, commit_lsn);
/* item_lsn of -1 means the item needs no further processing */
if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
return;
/*
* If the returned lsn is greater than what it contained before, update
* the location of the item in the AIL. If it is not, then do nothing.
* Items can never move backwards in the AIL.
*
* While the new lsn should usually be greater, it is possible that a
* later transaction completing simultaneously with an earlier one
* using the same item could complete first with a higher lsn. This
* would cause the earlier transaction to fail the test below.
*/
ailp = lip->li_ailp;
spin_lock(&ailp->xa_lock);
if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0) {
/*
* This will set the item's lsn to item_lsn and update the
* position of the item in the AIL.
*
* xfs_trans_ail_update() drops the AIL lock.
*/
xfs_trans_ail_update(ailp, lip, item_lsn);
} else {
spin_unlock(&ailp->xa_lock);
}
/*
* Now that we've repositioned the item in the AIL, unpin it so it can
* be flushed. Pass information about buffer stale state down from the
* log item flags, if anyone else stales the buffer we do not want to
* pay any attention to it.
*/
IOP_UNPIN(lip, 0);
}
/*
* This is typically called by the LM when a transaction has been fully
* committed to disk. It needs to unpin the items which have
* been logged by the transaction and update their positions
* in the AIL if necessary.
*
* This also gets called when the transactions didn't get written out
* because of an I/O error. Abortflag & XFS_LI_ABORTED is set then.
*/
STATIC void
xfs_trans_committed(
void *arg,
int abortflag)
{
struct xfs_trans *tp = arg;
struct xfs_log_item_desc *lidp, *next;
list_for_each_entry_safe(lidp, next, &tp->t_items, lid_trans) {
xfs_trans_item_committed(lidp->lid_item, tp->t_lsn, abortflag);
xfs_trans_free_item_desc(lidp);
}
xfs_trans_free(tp);
}
static inline void
xfs_log_item_batch_insert(
struct xfs_ail *ailp,
struct xfs_log_item **log_items,
int nr_items,
xfs_lsn_t commit_lsn)
{
int i;
spin_lock(&ailp->xa_lock);
/* xfs_trans_ail_update_bulk drops ailp->xa_lock */
xfs_trans_ail_update_bulk(ailp, log_items, nr_items, commit_lsn);
for (i = 0; i < nr_items; i++)
IOP_UNPIN(log_items[i], 0);
}
/*
* Bulk operation version of xfs_trans_committed that takes a log vector of
* items to insert into the AIL. This uses bulk AIL insertion techniques to
* minimise lock traffic.
*
* If we are called with the aborted flag set, it is because a log write during
* a CIL checkpoint commit has failed. In this case, all the items in the
* checkpoint have already gone through IOP_COMMITED and IOP_UNLOCK, which
* means that checkpoint commit abort handling is treated exactly the same
* as an iclog write error even though we haven't started any IO yet. Hence in
* this case all we need to do is IOP_COMMITTED processing, followed by an
* IOP_UNPIN(aborted) call.
*/
void
xfs_trans_committed_bulk(
struct xfs_ail *ailp,
struct xfs_log_vec *log_vector,
xfs_lsn_t commit_lsn,
int aborted)
{
#define LOG_ITEM_BATCH_SIZE 32
struct xfs_log_item *log_items[LOG_ITEM_BATCH_SIZE];
struct xfs_log_vec *lv;
int i = 0;
/* unpin all the log items */
for (lv = log_vector; lv; lv = lv->lv_next ) {
struct xfs_log_item *lip = lv->lv_item;
xfs_lsn_t item_lsn;
if (aborted)
lip->li_flags |= XFS_LI_ABORTED;
item_lsn = IOP_COMMITTED(lip, commit_lsn);
/* item_lsn of -1 means the item needs no further processing */
if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
continue;
/*
* if we are aborting the operation, no point in inserting the
* object into the AIL as we are in a shutdown situation.
*/
if (aborted) {
ASSERT(XFS_FORCED_SHUTDOWN(ailp->xa_mount));
IOP_UNPIN(lip, 1);
continue;
}
if (item_lsn != commit_lsn) {
/*
* Not a bulk update option due to unusual item_lsn.
* Push into AIL immediately, rechecking the lsn once
* we have the ail lock. Then unpin the item.
*/
spin_lock(&ailp->xa_lock);
if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0)
xfs_trans_ail_update(ailp, lip, item_lsn);
else
spin_unlock(&ailp->xa_lock);
IOP_UNPIN(lip, 0);
continue;
}
/* Item is a candidate for bulk AIL insert. */
log_items[i++] = lv->lv_item;
if (i >= LOG_ITEM_BATCH_SIZE) {
xfs_log_item_batch_insert(ailp, log_items,
LOG_ITEM_BATCH_SIZE, commit_lsn);
i = 0;
}
}
/* make sure we insert the remainder! */
if (i)
xfs_log_item_batch_insert(ailp, log_items, i, commit_lsn);
}
/*
* Called from the trans_commit code when we notice that the filesystem is in
* the middle of a forced shutdown.
*
* When we are called here, we have already pinned all the items in the
* transaction. However, neither IOP_COMMITTING or IOP_UNLOCK has been called
* so we can simply walk the items in the transaction, unpin them with an abort
* flag and then free the items. Note that unpinning the items can result in
* them being freed immediately, so we need to use a safe list traversal method
* here.
*/
STATIC void
xfs_trans_uncommit(
struct xfs_trans *tp,
uint flags)
{
struct xfs_log_item_desc *lidp, *n;
list_for_each_entry_safe(lidp, n, &tp->t_items, lid_trans) {
if (lidp->lid_flags & XFS_LID_DIRTY)
IOP_UNPIN(lidp->lid_item, 1);
}
xfs_trans_unreserve_and_mod_sb(tp);
xfs_trans_unreserve_and_mod_dquots(tp);
xfs_trans_free_items(tp, NULLCOMMITLSN, flags);
xfs_trans_free(tp);
}
/*
* Format the transaction direct to the iclog. This isolates the physical
* transaction commit operation from the logical operation and hence allows
* other methods to be introduced without affecting the existing commit path.
*/
static int
xfs_trans_commit_iclog(
struct xfs_mount *mp,
struct xfs_trans *tp,
xfs_lsn_t *commit_lsn,
int flags)
{
int shutdown;
int error;
int log_flags = 0;
struct xlog_in_core *commit_iclog;
#define XFS_TRANS_LOGVEC_COUNT 16
struct xfs_log_iovec log_vector_fast[XFS_TRANS_LOGVEC_COUNT];
struct xfs_log_iovec *log_vector;
uint nvec;
/*
* Ask each log item how many log_vector entries it will
* need so we can figure out how many to allocate.
* Try to avoid the kmem_alloc() call in the common case
* by using a vector from the stack when it fits.
*/
nvec = xfs_trans_count_vecs(tp);
if (nvec == 0) {
return ENOMEM; /* triggers a shutdown! */
} else if (nvec <= XFS_TRANS_LOGVEC_COUNT) {
log_vector = log_vector_fast;
} else {
log_vector = (xfs_log_iovec_t *)kmem_alloc(nvec *
sizeof(xfs_log_iovec_t),
KM_SLEEP);
}
/*
* Fill in the log_vector and pin the logged items, and
* then write the transaction to the log.
*/
xfs_trans_fill_vecs(tp, log_vector);
if (flags & XFS_TRANS_RELEASE_LOG_RES)
log_flags = XFS_LOG_REL_PERM_RESERV;
error = xfs_log_write(mp, log_vector, nvec, tp->t_ticket, &(tp->t_lsn));
/*
* The transaction is committed incore here, and can go out to disk
* at any time after this call. However, all the items associated
* with the transaction are still locked and pinned in memory.
*/
*commit_lsn = xfs_log_done(mp, tp->t_ticket, &commit_iclog, log_flags);
tp->t_commit_lsn = *commit_lsn;
trace_xfs_trans_commit_lsn(tp);
if (nvec > XFS_TRANS_LOGVEC_COUNT)
kmem_free(log_vector);
/*
* If we got a log write error. Unpin the logitems that we
* had pinned, clean up, free trans structure, and return error.
*/
if (error || *commit_lsn == -1) {
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
xfs_trans_uncommit(tp, flags|XFS_TRANS_ABORT);
return XFS_ERROR(EIO);
}
/*
* Once the transaction has committed, unused
* reservations need to be released and changes to
* the superblock need to be reflected in the in-core
* version. Do that now.
*/
xfs_trans_unreserve_and_mod_sb(tp);
/*
* Tell the LM to call the transaction completion routine
* when the log write with LSN commit_lsn completes (e.g.
* when the transaction commit really hits the on-disk log).
* After this call we cannot reference tp, because the call
* can happen at any time and the call will free the transaction
* structure pointed to by tp. The only case where we call
* the completion routine (xfs_trans_committed) directly is
* if the log is turned off on a debug kernel or we're
* running in simulation mode (the log is explicitly turned
* off).
*/
tp->t_logcb.cb_func = xfs_trans_committed;
tp->t_logcb.cb_arg = tp;
/*
* We need to pass the iclog buffer which was used for the
* transaction commit record into this function, and attach
* the callback to it. The callback must be attached before
* the items are unlocked to avoid racing with other threads
* waiting for an item to unlock.
*/
shutdown = xfs_log_notify(mp, commit_iclog, &(tp->t_logcb));
/*
* Mark this thread as no longer being in a transaction
*/
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
/*
* Once all the items of the transaction have been copied
* to the in core log and the callback is attached, the
* items can be unlocked.
*
* This will free descriptors pointing to items which were
* not logged since there is nothing more to do with them.
* For items which were logged, we will keep pointers to them
* so they can be unpinned after the transaction commits to disk.
* This will also stamp each modified meta-data item with
* the commit lsn of this transaction for dependency tracking
* purposes.
*/
xfs_trans_unlock_items(tp, *commit_lsn);
/*
* If we detected a log error earlier, finish committing
* the transaction now (unpin log items, etc).
*
* Order is critical here, to avoid using the transaction
* pointer after its been freed (by xfs_trans_committed
* either here now, or as a callback). We cannot do this
* step inside xfs_log_notify as was done earlier because
* of this issue.
*/
if (shutdown)
xfs_trans_committed(tp, XFS_LI_ABORTED);
/*
* Now that the xfs_trans_committed callback has been attached,
* and the items are released we can finally allow the iclog to
* go to disk.
*/
return xfs_log_release_iclog(mp, commit_iclog);
}
/*
* Walk the log items and allocate log vector structures for
* each item large enough to fit all the vectors they require.
* Note that this format differs from the old log vector format in
* that there is no transaction header in these log vectors.
*/
STATIC struct xfs_log_vec *
xfs_trans_alloc_log_vecs(
xfs_trans_t *tp)
{
struct xfs_log_item_desc *lidp;
struct xfs_log_vec *lv = NULL;
struct xfs_log_vec *ret_lv = NULL;
/* Bail out if we didn't find a log item. */
if (list_empty(&tp->t_items)) {
ASSERT(0);
return NULL;
}
list_for_each_entry(lidp, &tp->t_items, lid_trans) {
struct xfs_log_vec *new_lv;
/* Skip items which aren't dirty in this transaction. */
if (!(lidp->lid_flags & XFS_LID_DIRTY))
continue;
/* Skip items that do not have any vectors for writing */
lidp->lid_size = IOP_SIZE(lidp->lid_item);
if (!lidp->lid_size)
continue;
new_lv = kmem_zalloc(sizeof(*new_lv) +
lidp->lid_size * sizeof(struct xfs_log_iovec),
KM_SLEEP);
/* The allocated iovec region lies beyond the log vector. */
new_lv->lv_iovecp = (struct xfs_log_iovec *)&new_lv[1];
new_lv->lv_niovecs = lidp->lid_size;
new_lv->lv_item = lidp->lid_item;
if (!ret_lv)
ret_lv = new_lv;
else
lv->lv_next = new_lv;
lv = new_lv;
}
return ret_lv;
}
static int
xfs_trans_commit_cil(
struct xfs_mount *mp,
struct xfs_trans *tp,
xfs_lsn_t *commit_lsn,
int flags)
{
struct xfs_log_vec *log_vector;
/*
* Get each log item to allocate a vector structure for
* the log item to to pass to the log write code. The
* CIL commit code will format the vector and save it away.
*/
log_vector = xfs_trans_alloc_log_vecs(tp);
if (!log_vector)
return ENOMEM;
xfs_log_commit_cil(mp, tp, log_vector, commit_lsn, flags);
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
xfs_trans_free(tp);
return 0;
}
/*
* xfs_trans_commit
*
* Commit the given transaction to the log a/synchronously.
*
* XFS disk error handling mechanism is not based on a typical
* transaction abort mechanism. Logically after the filesystem
* gets marked 'SHUTDOWN', we can't let any new transactions
* be durable - ie. committed to disk - because some metadata might
* be inconsistent. In such cases, this returns an error, and the
* caller may assume that all locked objects joined to the transaction
* have already been unlocked as if the commit had succeeded.
* Do not reference the transaction structure after this call.
*/
int
_xfs_trans_commit(
struct xfs_trans *tp,
uint flags,
int *log_flushed)
{
struct xfs_mount *mp = tp->t_mountp;
xfs_lsn_t commit_lsn = -1;
int error = 0;
int log_flags = 0;
int sync = tp->t_flags & XFS_TRANS_SYNC;
/*
* Determine whether this commit is releasing a permanent
* log reservation or not.
*/
if (flags & XFS_TRANS_RELEASE_LOG_RES) {
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
log_flags = XFS_LOG_REL_PERM_RESERV;
}
/*
* If there is nothing to be logged by the transaction,
* then unlock all of the items associated with the
* transaction and free the transaction structure.
* Also make sure to return any reserved blocks to
* the free pool.
*/
if (!(tp->t_flags & XFS_TRANS_DIRTY))
goto out_unreserve;
if (XFS_FORCED_SHUTDOWN(mp)) {
error = XFS_ERROR(EIO);
goto out_unreserve;
}
ASSERT(tp->t_ticket != NULL);
/*
* If we need to update the superblock, then do it now.
*/
if (tp->t_flags & XFS_TRANS_SB_DIRTY)
xfs_trans_apply_sb_deltas(tp);
xfs_trans_apply_dquot_deltas(tp);
if (mp->m_flags & XFS_MOUNT_DELAYLOG)
error = xfs_trans_commit_cil(mp, tp, &commit_lsn, flags);
else
error = xfs_trans_commit_iclog(mp, tp, &commit_lsn, flags);
if (error == ENOMEM) {
xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);
error = XFS_ERROR(EIO);
goto out_unreserve;
}
/*
* If the transaction needs to be synchronous, then force the
* log out now and wait for it.
*/
if (sync) {
if (!error) {
error = _xfs_log_force_lsn(mp, commit_lsn,
XFS_LOG_SYNC, log_flushed);
}
XFS_STATS_INC(xs_trans_sync);
} else {
XFS_STATS_INC(xs_trans_async);
}
return error;
out_unreserve:
xfs_trans_unreserve_and_mod_sb(tp);
/*
* It is indeed possible for the transaction to be not dirty but
* the dqinfo portion to be. All that means is that we have some
* (non-persistent) quota reservations that need to be unreserved.
*/
xfs_trans_unreserve_and_mod_dquots(tp);
if (tp->t_ticket) {
commit_lsn = xfs_log_done(mp, tp->t_ticket, NULL, log_flags);
if (commit_lsn == -1 && !error)
error = XFS_ERROR(EIO);
}
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
xfs_trans_free_items(tp, NULLCOMMITLSN, error ? XFS_TRANS_ABORT : 0);
xfs_trans_free(tp);
XFS_STATS_INC(xs_trans_empty);
return error;
}
/*
* Unlock all of the transaction's items and free the transaction.
* The transaction must not have modified any of its items, because
* there is no way to restore them to their previous state.
*
* If the transaction has made a log reservation, make sure to release
* it as well.
*/
void
xfs_trans_cancel(
xfs_trans_t *tp,
int flags)
{
int log_flags;
xfs_mount_t *mp = tp->t_mountp;
/*
* See if the caller is being too lazy to figure out if
* the transaction really needs an abort.
*/
if ((flags & XFS_TRANS_ABORT) && !(tp->t_flags & XFS_TRANS_DIRTY))
flags &= ~XFS_TRANS_ABORT;
/*
* See if the caller is relying on us to shut down the
* filesystem. This happens in paths where we detect
* corruption and decide to give up.
*/
if ((tp->t_flags & XFS_TRANS_DIRTY) && !XFS_FORCED_SHUTDOWN(mp)) {
XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
}
#ifdef DEBUG
if (!(flags & XFS_TRANS_ABORT) && !XFS_FORCED_SHUTDOWN(mp)) {
struct xfs_log_item_desc *lidp;
list_for_each_entry(lidp, &tp->t_items, lid_trans)
ASSERT(!(lidp->lid_item->li_type == XFS_LI_EFD));
}
#endif
xfs_trans_unreserve_and_mod_sb(tp);
xfs_trans_unreserve_and_mod_dquots(tp);
if (tp->t_ticket) {
if (flags & XFS_TRANS_RELEASE_LOG_RES) {
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
log_flags = XFS_LOG_REL_PERM_RESERV;
} else {
log_flags = 0;
}
xfs_log_done(mp, tp->t_ticket, NULL, log_flags);
}
/* mark this thread as no longer being in a transaction */
current_restore_flags_nested(&tp->t_pflags, PF_FSTRANS);
xfs_trans_free_items(tp, NULLCOMMITLSN, flags);
xfs_trans_free(tp);
}
/*
* Roll from one trans in the sequence of PERMANENT transactions to
* the next: permanent transactions are only flushed out when
* committed with XFS_TRANS_RELEASE_LOG_RES, but we still want as soon
* as possible to let chunks of it go to the log. So we commit the
* chunk we've been working on and get a new transaction to continue.
*/
int
xfs_trans_roll(
struct xfs_trans **tpp,
struct xfs_inode *dp)
{
struct xfs_trans *trans;
unsigned int logres, count;
int error;
/*
* Ensure that the inode is always logged.
*/
trans = *tpp;
xfs_trans_log_inode(trans, dp, XFS_ILOG_CORE);
/*
* Copy the critical parameters from one trans to the next.
*/
logres = trans->t_log_res;
count = trans->t_log_count;
*tpp = xfs_trans_dup(trans);
/*
* Commit the current transaction.
* If this commit failed, then it'd just unlock those items that
* are not marked ihold. That also means that a filesystem shutdown
* is in progress. The caller takes the responsibility to cancel
* the duplicate transaction that gets returned.
*/
error = xfs_trans_commit(trans, 0);
if (error)
return (error);
trans = *tpp;
/*
* transaction commit worked ok so we can drop the extra ticket
* reference that we gained in xfs_trans_dup()
*/
xfs_log_ticket_put(trans->t_ticket);
/*
* Reserve space in the log for th next transaction.
* This also pushes items in the "AIL", the list of logged items,
* out to disk if they are taking up space at the tail of the log
* that we want to use. This requires that either nothing be locked
* across this call, or that anything that is locked be logged in
* the prior and the next transactions.
*/
error = xfs_trans_reserve(trans, 0, logres, 0,
XFS_TRANS_PERM_LOG_RES, count);
/*
* Ensure that the inode is in the new transaction and locked.
*/
if (error)
return error;
xfs_trans_ijoin(trans, dp);
return 0;
}