linux_dsm_epyc7002/fs/xfs/xfs_bmap_item.c

668 lines
17 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_shared.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_bmap_item.h"
#include "xfs_log.h"
#include "xfs_bmap.h"
#include "xfs_icache.h"
#include "xfs_bmap_btree.h"
#include "xfs_trans_space.h"
#include "xfs_error.h"
#include "xfs_log_priv.h"
#include "xfs_log_recover.h"
#include "xfs_quota.h"
kmem_zone_t *xfs_bui_zone;
kmem_zone_t *xfs_bud_zone;
static const struct xfs_item_ops xfs_bui_item_ops;
static inline struct xfs_bui_log_item *BUI_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_bui_log_item, bui_item);
}
STATIC void
xfs_bui_item_free(
struct xfs_bui_log_item *buip)
{
kmem_cache_free(xfs_bui_zone, buip);
}
/*
* Freeing the BUI requires that we remove it from the AIL if it has already
* been placed there. However, the BUI may not yet have been placed in the AIL
* when called by xfs_bui_release() from BUD processing due to the ordering of
* committed vs unpin operations in bulk insert operations. Hence the reference
* count to ensure only the last caller frees the BUI.
*/
STATIC void
xfs_bui_release(
struct xfs_bui_log_item *buip)
{
ASSERT(atomic_read(&buip->bui_refcount) > 0);
if (atomic_dec_and_test(&buip->bui_refcount)) {
xfs_trans_ail_delete(&buip->bui_item, SHUTDOWN_LOG_IO_ERROR);
xfs_bui_item_free(buip);
}
}
STATIC void
xfs_bui_item_size(
struct xfs_log_item *lip,
int *nvecs,
int *nbytes)
{
struct xfs_bui_log_item *buip = BUI_ITEM(lip);
*nvecs += 1;
*nbytes += xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents);
}
/*
* This is called to fill in the vector of log iovecs for the
* given bui log item. We use only 1 iovec, and we point that
* at the bui_log_format structure embedded in the bui item.
* It is at this point that we assert that all of the extent
* slots in the bui item have been filled.
*/
STATIC void
xfs_bui_item_format(
struct xfs_log_item *lip,
struct xfs_log_vec *lv)
{
struct xfs_bui_log_item *buip = BUI_ITEM(lip);
struct xfs_log_iovec *vecp = NULL;
ASSERT(atomic_read(&buip->bui_next_extent) ==
buip->bui_format.bui_nextents);
buip->bui_format.bui_type = XFS_LI_BUI;
buip->bui_format.bui_size = 1;
xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUI_FORMAT, &buip->bui_format,
xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents));
}
/*
* The unpin operation is the last place an BUI is manipulated in the log. It is
* either inserted in the AIL or aborted in the event of a log I/O error. In
* either case, the BUI transaction has been successfully committed to make it
* this far. Therefore, we expect whoever committed the BUI to either construct
* and commit the BUD or drop the BUD's reference in the event of error. Simply
* drop the log's BUI reference now that the log is done with it.
*/
STATIC void
xfs_bui_item_unpin(
struct xfs_log_item *lip,
int remove)
{
struct xfs_bui_log_item *buip = BUI_ITEM(lip);
xfs_bui_release(buip);
}
/*
* The BUI has been either committed or aborted if the transaction has been
* cancelled. If the transaction was cancelled, an BUD isn't going to be
* constructed and thus we free the BUI here directly.
*/
STATIC void
xfs: split iop_unlock The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-29 09:27:32 +07:00
xfs_bui_item_release(
struct xfs_log_item *lip)
{
xfs: split iop_unlock The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-29 09:27:32 +07:00
xfs_bui_release(BUI_ITEM(lip));
}
/*
* Allocate and initialize an bui item with the given number of extents.
*/
STATIC struct xfs_bui_log_item *
xfs_bui_init(
struct xfs_mount *mp)
{
struct xfs_bui_log_item *buip;
buip = kmem_cache_zalloc(xfs_bui_zone, GFP_KERNEL | __GFP_NOFAIL);
xfs_log_item_init(mp, &buip->bui_item, XFS_LI_BUI, &xfs_bui_item_ops);
buip->bui_format.bui_nextents = XFS_BUI_MAX_FAST_EXTENTS;
buip->bui_format.bui_id = (uintptr_t)(void *)buip;
atomic_set(&buip->bui_next_extent, 0);
atomic_set(&buip->bui_refcount, 2);
return buip;
}
static inline struct xfs_bud_log_item *BUD_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_bud_log_item, bud_item);
}
STATIC void
xfs_bud_item_size(
struct xfs_log_item *lip,
int *nvecs,
int *nbytes)
{
*nvecs += 1;
*nbytes += sizeof(struct xfs_bud_log_format);
}
/*
* This is called to fill in the vector of log iovecs for the
* given bud log item. We use only 1 iovec, and we point that
* at the bud_log_format structure embedded in the bud item.
* It is at this point that we assert that all of the extent
* slots in the bud item have been filled.
*/
STATIC void
xfs_bud_item_format(
struct xfs_log_item *lip,
struct xfs_log_vec *lv)
{
struct xfs_bud_log_item *budp = BUD_ITEM(lip);
struct xfs_log_iovec *vecp = NULL;
budp->bud_format.bud_type = XFS_LI_BUD;
budp->bud_format.bud_size = 1;
xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUD_FORMAT, &budp->bud_format,
sizeof(struct xfs_bud_log_format));
}
/*
* The BUD is either committed or aborted if the transaction is cancelled. If
* the transaction is cancelled, drop our reference to the BUI and free the
* BUD.
*/
STATIC void
xfs: split iop_unlock The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-29 09:27:32 +07:00
xfs_bud_item_release(
struct xfs_log_item *lip)
{
struct xfs_bud_log_item *budp = BUD_ITEM(lip);
xfs: split iop_unlock The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-29 09:27:32 +07:00
xfs_bui_release(budp->bud_buip);
kmem_cache_free(xfs_bud_zone, budp);
}
static const struct xfs_item_ops xfs_bud_item_ops = {
.flags = XFS_ITEM_RELEASE_WHEN_COMMITTED,
.iop_size = xfs_bud_item_size,
.iop_format = xfs_bud_item_format,
xfs: split iop_unlock The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-29 09:27:32 +07:00
.iop_release = xfs_bud_item_release,
};
static struct xfs_bud_log_item *
xfs_trans_get_bud(
struct xfs_trans *tp,
struct xfs_bui_log_item *buip)
{
struct xfs_bud_log_item *budp;
budp = kmem_cache_zalloc(xfs_bud_zone, GFP_KERNEL | __GFP_NOFAIL);
xfs_log_item_init(tp->t_mountp, &budp->bud_item, XFS_LI_BUD,
&xfs_bud_item_ops);
budp->bud_buip = buip;
budp->bud_format.bud_bui_id = buip->bui_format.bui_id;
xfs_trans_add_item(tp, &budp->bud_item);
return budp;
}
/*
* Finish an bmap update and log it to the BUD. Note that the
* transaction is marked dirty regardless of whether the bmap update
* succeeds or fails to support the BUI/BUD lifecycle rules.
*/
static int
xfs_trans_log_finish_bmap_update(
struct xfs_trans *tp,
struct xfs_bud_log_item *budp,
enum xfs_bmap_intent_type type,
struct xfs_inode *ip,
int whichfork,
xfs_fileoff_t startoff,
xfs_fsblock_t startblock,
xfs_filblks_t *blockcount,
xfs_exntst_t state)
{
int error;
error = xfs_bmap_finish_one(tp, ip, type, whichfork, startoff,
startblock, blockcount, state);
/*
* Mark the transaction dirty, even on error. This ensures the
* transaction is aborted, which:
*
* 1.) releases the BUI and frees the BUD
* 2.) shuts down the filesystem
*/
tp->t_flags |= XFS_TRANS_DIRTY;
set_bit(XFS_LI_DIRTY, &budp->bud_item.li_flags);
return error;
}
/* Sort bmap intents by inode. */
static int
xfs_bmap_update_diff_items(
void *priv,
struct list_head *a,
struct list_head *b)
{
struct xfs_bmap_intent *ba;
struct xfs_bmap_intent *bb;
ba = container_of(a, struct xfs_bmap_intent, bi_list);
bb = container_of(b, struct xfs_bmap_intent, bi_list);
return ba->bi_owner->i_ino - bb->bi_owner->i_ino;
}
/* Set the map extent flags for this mapping. */
static void
xfs_trans_set_bmap_flags(
struct xfs_map_extent *bmap,
enum xfs_bmap_intent_type type,
int whichfork,
xfs_exntst_t state)
{
bmap->me_flags = 0;
switch (type) {
case XFS_BMAP_MAP:
case XFS_BMAP_UNMAP:
bmap->me_flags = type;
break;
default:
ASSERT(0);
}
if (state == XFS_EXT_UNWRITTEN)
bmap->me_flags |= XFS_BMAP_EXTENT_UNWRITTEN;
if (whichfork == XFS_ATTR_FORK)
bmap->me_flags |= XFS_BMAP_EXTENT_ATTR_FORK;
}
/* Log bmap updates in the intent item. */
STATIC void
xfs_bmap_update_log_item(
struct xfs_trans *tp,
struct xfs_bui_log_item *buip,
struct xfs_bmap_intent *bmap)
{
uint next_extent;
struct xfs_map_extent *map;
tp->t_flags |= XFS_TRANS_DIRTY;
set_bit(XFS_LI_DIRTY, &buip->bui_item.li_flags);
/*
* atomic_inc_return gives us the value after the increment;
* we want to use it as an array index so we need to subtract 1 from
* it.
*/
next_extent = atomic_inc_return(&buip->bui_next_extent) - 1;
ASSERT(next_extent < buip->bui_format.bui_nextents);
map = &buip->bui_format.bui_extents[next_extent];
map->me_owner = bmap->bi_owner->i_ino;
map->me_startblock = bmap->bi_bmap.br_startblock;
map->me_startoff = bmap->bi_bmap.br_startoff;
map->me_len = bmap->bi_bmap.br_blockcount;
xfs_trans_set_bmap_flags(map, bmap->bi_type, bmap->bi_whichfork,
bmap->bi_bmap.br_state);
}
static struct xfs_log_item *
xfs_bmap_update_create_intent(
struct xfs_trans *tp,
struct list_head *items,
unsigned int count,
bool sort)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_bui_log_item *buip = xfs_bui_init(mp);
struct xfs_bmap_intent *bmap;
ASSERT(count == XFS_BUI_MAX_FAST_EXTENTS);
xfs_trans_add_item(tp, &buip->bui_item);
if (sort)
list_sort(mp, items, xfs_bmap_update_diff_items);
list_for_each_entry(bmap, items, bi_list)
xfs_bmap_update_log_item(tp, buip, bmap);
return &buip->bui_item;
}
/* Get an BUD so we can process all the deferred rmap updates. */
static struct xfs_log_item *
xfs_bmap_update_create_done(
struct xfs_trans *tp,
struct xfs_log_item *intent,
unsigned int count)
{
return &xfs_trans_get_bud(tp, BUI_ITEM(intent))->bud_item;
}
/* Process a deferred rmap update. */
STATIC int
xfs_bmap_update_finish_item(
struct xfs_trans *tp,
struct xfs_log_item *done,
struct list_head *item,
struct xfs_btree_cur **state)
{
struct xfs_bmap_intent *bmap;
xfs_filblks_t count;
int error;
bmap = container_of(item, struct xfs_bmap_intent, bi_list);
count = bmap->bi_bmap.br_blockcount;
error = xfs_trans_log_finish_bmap_update(tp, BUD_ITEM(done),
bmap->bi_type,
bmap->bi_owner, bmap->bi_whichfork,
bmap->bi_bmap.br_startoff,
bmap->bi_bmap.br_startblock,
&count,
bmap->bi_bmap.br_state);
if (!error && count > 0) {
ASSERT(bmap->bi_type == XFS_BMAP_UNMAP);
bmap->bi_bmap.br_blockcount = count;
return -EAGAIN;
}
kmem_free(bmap);
return error;
}
/* Abort all pending BUIs. */
STATIC void
xfs_bmap_update_abort_intent(
struct xfs_log_item *intent)
{
xfs_bui_release(BUI_ITEM(intent));
}
/* Cancel a deferred rmap update. */
STATIC void
xfs_bmap_update_cancel_item(
struct list_head *item)
{
struct xfs_bmap_intent *bmap;
bmap = container_of(item, struct xfs_bmap_intent, bi_list);
kmem_free(bmap);
}
const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
.max_items = XFS_BUI_MAX_FAST_EXTENTS,
.create_intent = xfs_bmap_update_create_intent,
.abort_intent = xfs_bmap_update_abort_intent,
.create_done = xfs_bmap_update_create_done,
.finish_item = xfs_bmap_update_finish_item,
.cancel_item = xfs_bmap_update_cancel_item,
};
/*
* Process a bmap update intent item that was recovered from the log.
* We need to update some inode's bmbt.
*/
STATIC int
xfs_bui_item_recover(
struct xfs_log_item *lip,
struct xfs_trans *parent_tp)
{
struct xfs_bmbt_irec irec;
struct xfs_bui_log_item *buip = BUI_ITEM(lip);
struct xfs_trans *tp;
struct xfs_inode *ip = NULL;
struct xfs_mount *mp = parent_tp->t_mountp;
struct xfs_map_extent *bmap;
struct xfs_bud_log_item *budp;
xfs_fsblock_t startblock_fsb;
xfs_fsblock_t inode_fsb;
xfs_filblks_t count;
xfs_exntst_t state;
enum xfs_bmap_intent_type type;
bool op_ok;
unsigned int bui_type;
int whichfork;
int error = 0;
/* Only one mapping operation per BUI... */
if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
return -EFSCORRUPTED;
/*
* First check the validity of the extent described by the
* BUI. If anything is bad, then toss the BUI.
*/
bmap = &buip->bui_format.bui_extents[0];
startblock_fsb = XFS_BB_TO_FSB(mp,
XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
XFS_INO_TO_FSB(mp, bmap->me_owner)));
switch (bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK) {
case XFS_BMAP_MAP:
case XFS_BMAP_UNMAP:
op_ok = true;
break;
default:
op_ok = false;
break;
}
if (!op_ok || startblock_fsb == 0 ||
bmap->me_len == 0 ||
inode_fsb == 0 ||
startblock_fsb >= mp->m_sb.sb_dblocks ||
bmap->me_len >= mp->m_sb.sb_agblocks ||
inode_fsb >= mp->m_sb.sb_dblocks ||
(bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS))
return -EFSCORRUPTED;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK), 0, 0, &tp);
if (error)
return error;
/*
* Recovery stashes all deferred ops during intent processing and
* finishes them on completion. Transfer current dfops state to this
* transaction and transfer the result back before we return.
*/
xfs_defer_move(tp, parent_tp);
budp = xfs_trans_get_bud(tp, buip);
/* Grab the inode. */
error = xfs_iget(mp, tp, bmap->me_owner, 0, XFS_ILOCK_EXCL, &ip);
if (error)
goto err_inode;
error = xfs_qm_dqattach_locked(ip, false);
if (error)
goto err_inode;
if (VFS_I(ip)->i_nlink == 0)
xfs_iflags_set(ip, XFS_IRECOVERY);
/* Process deferred bmap item. */
state = (bmap->me_flags & XFS_BMAP_EXTENT_UNWRITTEN) ?
XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
whichfork = (bmap->me_flags & XFS_BMAP_EXTENT_ATTR_FORK) ?
XFS_ATTR_FORK : XFS_DATA_FORK;
bui_type = bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK;
switch (bui_type) {
case XFS_BMAP_MAP:
case XFS_BMAP_UNMAP:
type = bui_type;
break;
default:
XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
error = -EFSCORRUPTED;
xfs: log recovery should replay deferred ops in order As part of testing log recovery with dm_log_writes, Amir Goldstein discovered an error in the deferred ops recovery that lead to corruption of the filesystem metadata if a reflink+rmap filesystem happened to shut down midway through a CoW remap: "This is what happens [after failed log recovery]: "Phase 1 - find and verify superblock... "Phase 2 - using internal log " - zero log... " - scan filesystem freespace and inode maps... " - found root inode chunk "Phase 3 - for each AG... " - scan (but don't clear) agi unlinked lists... " - process known inodes and perform inode discovery... " - agno = 0 "data fork in regular inode 134 claims CoW block 376 "correcting nextents for inode 134 "bad data fork in inode 134 "would have cleared inode 134" Hou Tao dissected the log contents of exactly such a crash: "According to the implementation of xfs_defer_finish(), these ops should be completed in the following sequence: "Have been done: "(1) CUI: Oper (160) "(2) BUI: Oper (161) "(3) CUD: Oper (194), for CUI Oper (160) "(4) RUI A: Oper (197), free rmap [0x155, 2, -9] "Should be done: "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI A "(8) RUD: for RUI B "Actually be done by xlog_recover_process_intents() "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI B "(8) RUD: for RUI A "So the rmap entry [0x155, 2, -9] for COW should be freed firstly, then a new rmap entry [0x155, 2, 137] will be added. However, as we can see from the log record in post_mount.log (generated after umount) and the trace print, the new rmap entry [0x155, 2, 137] are added firstly, then the rmap entry [0x155, 2, -9] are freed." When reconstructing the internal log state from the log items found on disk, it's required that deferred ops replay in exactly the same order that they would have had the filesystem not gone down. However, replaying unfinished deferred ops can create /more/ deferred ops. These new deferred ops are finished in the wrong order. This causes fs corruption and replay crashes, so let's create a single defer_ops to handle the subsequent ops created during replay, then use one single transaction at the end of log recovery to ensure that everything is replayed in the same order as they're supposed to be. Reported-by: Amir Goldstein <amir73il@gmail.com> Analyzed-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-22 11:53:02 +07:00
goto err_inode;
}
xfs_trans_ijoin(tp, ip, 0);
count = bmap->me_len;
error = xfs_trans_log_finish_bmap_update(tp, budp, type, ip, whichfork,
bmap->me_startoff, bmap->me_startblock, &count, state);
if (error)
xfs: log recovery should replay deferred ops in order As part of testing log recovery with dm_log_writes, Amir Goldstein discovered an error in the deferred ops recovery that lead to corruption of the filesystem metadata if a reflink+rmap filesystem happened to shut down midway through a CoW remap: "This is what happens [after failed log recovery]: "Phase 1 - find and verify superblock... "Phase 2 - using internal log " - zero log... " - scan filesystem freespace and inode maps... " - found root inode chunk "Phase 3 - for each AG... " - scan (but don't clear) agi unlinked lists... " - process known inodes and perform inode discovery... " - agno = 0 "data fork in regular inode 134 claims CoW block 376 "correcting nextents for inode 134 "bad data fork in inode 134 "would have cleared inode 134" Hou Tao dissected the log contents of exactly such a crash: "According to the implementation of xfs_defer_finish(), these ops should be completed in the following sequence: "Have been done: "(1) CUI: Oper (160) "(2) BUI: Oper (161) "(3) CUD: Oper (194), for CUI Oper (160) "(4) RUI A: Oper (197), free rmap [0x155, 2, -9] "Should be done: "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI A "(8) RUD: for RUI B "Actually be done by xlog_recover_process_intents() "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI B "(8) RUD: for RUI A "So the rmap entry [0x155, 2, -9] for COW should be freed firstly, then a new rmap entry [0x155, 2, 137] will be added. However, as we can see from the log record in post_mount.log (generated after umount) and the trace print, the new rmap entry [0x155, 2, 137] are added firstly, then the rmap entry [0x155, 2, -9] are freed." When reconstructing the internal log state from the log items found on disk, it's required that deferred ops replay in exactly the same order that they would have had the filesystem not gone down. However, replaying unfinished deferred ops can create /more/ deferred ops. These new deferred ops are finished in the wrong order. This causes fs corruption and replay crashes, so let's create a single defer_ops to handle the subsequent ops created during replay, then use one single transaction at the end of log recovery to ensure that everything is replayed in the same order as they're supposed to be. Reported-by: Amir Goldstein <amir73il@gmail.com> Analyzed-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-22 11:53:02 +07:00
goto err_inode;
if (count > 0) {
ASSERT(type == XFS_BMAP_UNMAP);
irec.br_startblock = bmap->me_startblock;
irec.br_blockcount = count;
irec.br_startoff = bmap->me_startoff;
irec.br_state = state;
xfs_bmap_unmap_extent(tp, ip, &irec);
}
xfs_defer_capture(parent_tp, tp);
error = xfs_trans_commit(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_irele(ip);
return error;
err_inode:
xfs_defer_move(parent_tp, tp);
xfs_trans_cancel(tp);
if (ip) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_irele(ip);
}
return error;
}
STATIC bool
xfs_bui_item_match(
struct xfs_log_item *lip,
uint64_t intent_id)
{
return BUI_ITEM(lip)->bui_format.bui_id == intent_id;
}
static const struct xfs_item_ops xfs_bui_item_ops = {
.iop_size = xfs_bui_item_size,
.iop_format = xfs_bui_item_format,
.iop_unpin = xfs_bui_item_unpin,
.iop_release = xfs_bui_item_release,
.iop_recover = xfs_bui_item_recover,
.iop_match = xfs_bui_item_match,
};
/*
* Copy an BUI format buffer from the given buf, and into the destination
* BUI format structure. The BUI/BUD items were designed not to need any
* special alignment handling.
*/
static int
xfs_bui_copy_format(
struct xfs_log_iovec *buf,
struct xfs_bui_log_format *dst_bui_fmt)
{
struct xfs_bui_log_format *src_bui_fmt;
uint len;
src_bui_fmt = buf->i_addr;
len = xfs_bui_log_format_sizeof(src_bui_fmt->bui_nextents);
if (buf->i_len == len) {
memcpy(dst_bui_fmt, src_bui_fmt, len);
return 0;
}
XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, NULL);
return -EFSCORRUPTED;
}
/*
* This routine is called to create an in-core extent bmap update
* item from the bui format structure which was logged on disk.
* It allocates an in-core bui, copies the extents from the format
* structure into it, and adds the bui to the AIL with the given
* LSN.
*/
STATIC int
xlog_recover_bui_commit_pass2(
struct xlog *log,
struct list_head *buffer_list,
struct xlog_recover_item *item,
xfs_lsn_t lsn)
{
int error;
struct xfs_mount *mp = log->l_mp;
struct xfs_bui_log_item *buip;
struct xfs_bui_log_format *bui_formatp;
bui_formatp = item->ri_buf[0].i_addr;
if (bui_formatp->bui_nextents != XFS_BUI_MAX_FAST_EXTENTS) {
XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
return -EFSCORRUPTED;
}
buip = xfs_bui_init(mp);
error = xfs_bui_copy_format(&item->ri_buf[0], &buip->bui_format);
if (error) {
xfs_bui_item_free(buip);
return error;
}
atomic_set(&buip->bui_next_extent, bui_formatp->bui_nextents);
/*
* Insert the intent into the AIL directly and drop one reference so
* that finishing or canceling the work will drop the other.
*/
xfs_trans_ail_insert(log->l_ailp, &buip->bui_item, lsn);
xfs_bui_release(buip);
return 0;
}
const struct xlog_recover_item_ops xlog_bui_item_ops = {
.item_type = XFS_LI_BUI,
.commit_pass2 = xlog_recover_bui_commit_pass2,
};
/*
* This routine is called when an BUD format structure is found in a committed
* transaction in the log. Its purpose is to cancel the corresponding BUI if it
* was still in the log. To do this it searches the AIL for the BUI with an id
* equal to that in the BUD format structure. If we find it we drop the BUD
* reference, which removes the BUI from the AIL and frees it.
*/
STATIC int
xlog_recover_bud_commit_pass2(
struct xlog *log,
struct list_head *buffer_list,
struct xlog_recover_item *item,
xfs_lsn_t lsn)
{
struct xfs_bud_log_format *bud_formatp;
bud_formatp = item->ri_buf[0].i_addr;
if (item->ri_buf[0].i_len != sizeof(struct xfs_bud_log_format)) {
XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
return -EFSCORRUPTED;
}
xlog_recover_release_intent(log, XFS_LI_BUI, bud_formatp->bud_bui_id);
return 0;
}
const struct xlog_recover_item_ops xlog_bud_item_ops = {
.item_type = XFS_LI_BUD,
.commit_pass2 = xlog_recover_bud_commit_pass2,
};