From: Brian Foster bfoster@redhat.com

commit f74681ba2006434be195402e0b15fc5763cddd7e upstream.

[Slightly modify xfs_trans_alloc() to fix a merge conflict due to missing "atomic_inc(&mp->m_active_trans)" statement in v5.9 kernel]

The rmapbt extent swap algorithm remaps individual extents between the source inode and the target to trigger reverse mapping metadata updates. If either inode straddles a format or other bmap allocation boundary, the individual unmap and map cycles can trigger repeated bmap block allocations and frees as the extent count bounces back and forth across the boundary. While net block usage is bound across the swap operation, this behavior can prematurely exhaust the transaction block reservation because it continuously drains as the transaction rolls. Each allocation accounts against the reservation and each free returns to global free space on transaction roll.

The previous workaround to this problem attempted to detect this boundary condition and provide surplus block reservation to acommodate it. This is insufficient because more remaps can occur than implied by the extent counts; if start offset boundaries are not aligned between the two inodes, for example.

To address this problem more generically and dynamically, add a transaction accounting mode that returns freed blocks to the transaction reservation instead of the superblock counters on transaction roll and use it when the rmapbt based algorithm is active. This allows the chain of remap transactions to preserve the block reservation based own its own frees and prevent premature exhaustion regardless of the remap pattern. Note that this is only safe for superblocks with lazy sb accounting, but the latter is required for v5 supers and the rmap feature depends on v5.

Fixes: b3fed434822d0 ("xfs: account format bouncing into rmapbt swapext tx reservation") Root-caused-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-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 Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Chandan Babu R chandan.babu@oracle.com --- fs/xfs/libxfs/xfs_shared.h | 1 + fs/xfs/xfs_bmap_util.c | 18 +++++++++--------- fs/xfs/xfs_trans.c | 19 ++++++++++++++++++- 3 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h index c45acbd3add9..708feb8eac76 100644 --- a/fs/xfs/libxfs/xfs_shared.h +++ b/fs/xfs/libxfs/xfs_shared.h @@ -65,6 +65,7 @@ void xfs_log_get_max_trans_res(struct xfs_mount *mp, #define XFS_TRANS_DQ_DIRTY 0x10 /* at least one dquot in trx dirty */ #define XFS_TRANS_RESERVE 0x20 /* OK to use reserved data blocks */ #define XFS_TRANS_NO_WRITECOUNT 0x40 /* do not elevate SB writecount */ +#define XFS_TRANS_RES_FDBLKS 0x80 /* reserve newly freed blocks */ /* * LOWMODE is used by the allocator to activate the lowspace algorithm - when * free space is running low the extent allocator may choose to allocate an diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 12c12c2ef241..5eab15dde4e6 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1740,6 +1740,7 @@ xfs_swap_extents( int lock_flags; uint64_t f; int resblks = 0; + unsigned int flags = 0;

/* * Lock the inodes against other IO, page faults and truncate to @@ -1795,17 +1796,16 @@ xfs_swap_extents( resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w);

/* - * Handle the corner case where either inode might straddle the - * btree format boundary. If so, the inode could bounce between - * btree <-> extent format on unmap -> remap cycles, freeing and - * allocating a bmapbt block each time. + * If either inode straddles a bmapbt block allocation boundary, + * the rmapbt algorithm triggers repeated allocs and frees as + * extents are remapped. This can exhaust the block reservation + * prematurely and cause shutdown. Return freed blocks to the + * transaction reservation to counter this behavior. */ - if (ipnext == (XFS_IFORK_MAXEXT(ip, w) + 1)) - resblks += XFS_IFORK_MAXEXT(ip, w); - if (tipnext == (XFS_IFORK_MAXEXT(tip, w) + 1)) - resblks += XFS_IFORK_MAXEXT(tip, w); + flags |= XFS_TRANS_RES_FDBLKS; } - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags, + &tp); if (error) goto out_unlock;

diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index 2ba9f071c5e9..47acf4096022 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -107,7 +107,8 @@ xfs_trans_dup(

ntp->t_flags = XFS_TRANS_PERM_LOG_RES | (tp->t_flags & XFS_TRANS_RESERVE) | - (tp->t_flags & XFS_TRANS_NO_WRITECOUNT); + (tp->t_flags & XFS_TRANS_NO_WRITECOUNT) | + (tp->t_flags & XFS_TRANS_RES_FDBLKS); /* We gave our writer reference to the new transaction */ tp->t_flags |= XFS_TRANS_NO_WRITECOUNT; ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket); @@ -273,6 +274,8 @@ xfs_trans_alloc( */ WARN_ON(resp->tr_logres > 0 && mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE); + ASSERT(!(flags & XFS_TRANS_RES_FDBLKS) || + xfs_sb_version_haslazysbcount(&mp->m_sb)); atomic_inc(&mp->m_active_trans);

tp->t_magic = XFS_TRANS_HEADER_MAGIC; @@ -368,6 +371,20 @@ xfs_trans_mod_sb( tp->t_blk_res_used += (uint)-delta; if (tp->t_blk_res_used > tp->t_blk_res) xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); + } else if (delta > 0 && (tp->t_flags & XFS_TRANS_RES_FDBLKS)) { + int64_t blkres_delta; + + /* + * Return freed blocks directly to the reservation + * instead of the global pool, being careful not to + * overflow the trans counter. This is used to preserve + * reservation across chains of transaction rolls that + * repeatedly free and allocate blocks. + */ + blkres_delta = min_t(int64_t, delta, + UINT_MAX - tp->t_blk_res); + tp->t_blk_res += blkres_delta; + delta -= blkres_delta; } tp->t_fdblocks_delta += delta; if (xfs_sb_version_haslazysbcount(&mp->m_sb))

From: "Darrick J. Wong" darrick.wong@oracle.com

commit 00fd1d56dd08a8ceaa9e4ee1a41fefd9f6c6bc7d upstream.

The existing reflink remapping loop has some structural problems that need addressing:

The biggest problem is that we create one transaction for each extent in the source file without accounting for the number of mappings there are for the same range in the destination file. In other words, we don't know the number of remap operations that will be necessary and we therefore cannot guess the block reservation required. On highly fragmented filesystems (e.g. ones with active dedupe) we guess wrong, run out of block reservation, and fail.

The second problem is that we don't actually use the bmap intents to their full potential -- instead of calling bunmapi directly and having to deal with its backwards operation, we could call the deferred ops xfs_bmap_unmap_extent and xfs_refcount_decrease_extent instead. This makes the frontend loop much simpler.

Solve all of these problems by refactoring the remapping loops so that we only perform one remapping operation per transaction, and each operation only tries to remap a single extent from source to dest.

Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Brian Foster bfoster@redhat.com Reported-by: Edwin Török edwin@etorok.net Tested-by: Edwin Török edwin@etorok.net Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Chandan Babu R chandan.babu@oracle.com --- fs/xfs/libxfs/xfs_bmap.h | 13 ++- fs/xfs/xfs_reflink.c | 238 +++++++++++++++++++++------------------ fs/xfs/xfs_trace.h | 52 +-------- 3 files changed, 141 insertions(+), 162 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h index b5363c6c88af..a51c2b13a51a 100644 --- a/fs/xfs/libxfs/xfs_bmap.h +++ b/fs/xfs/libxfs/xfs_bmap.h @@ -158,6 +158,13 @@ static inline int xfs_bmapi_whichfork(int bmapi_flags) { BMAP_ATTRFORK, "ATTR" }, \ { BMAP_COWFORK, "COW" }

+/* Return true if the extent is an allocated extent, written or not. */ +static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec) +{ + return irec->br_startblock != HOLESTARTBLOCK && + irec->br_startblock != DELAYSTARTBLOCK && + !isnullstartblock(irec->br_startblock); +}

/* * Return true if the extent is a real, allocated extent, or false if it is a @@ -165,10 +172,8 @@ static inline int xfs_bmapi_whichfork(int bmapi_flags) */ static inline bool xfs_bmap_is_written_extent(struct xfs_bmbt_irec *irec) { - return irec->br_state != XFS_EXT_UNWRITTEN && - irec->br_startblock != HOLESTARTBLOCK && - irec->br_startblock != DELAYSTARTBLOCK && - !isnullstartblock(irec->br_startblock); + return xfs_bmap_is_real_extent(irec) && + irec->br_state != XFS_EXT_UNWRITTEN; }

/* diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 77b7ace04ffd..01191ff46647 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -986,41 +986,28 @@ xfs_reflink_ag_has_free_space( }

/* - * Unmap a range of blocks from a file, then map other blocks into the hole. - * The range to unmap is (destoff : destoff + srcioff + irec->br_blockcount). - * The extent irec is mapped into dest at irec->br_startoff. + * Remap the given extent into the file. The dmap blockcount will be set to + * the number of blocks that were actually remapped. */ STATIC int xfs_reflink_remap_extent( struct xfs_inode *ip, - struct xfs_bmbt_irec *irec, - xfs_fileoff_t destoff, + struct xfs_bmbt_irec *dmap, xfs_off_t new_isize) { + struct xfs_bmbt_irec smap; struct xfs_mount *mp = ip->i_mount; - bool real_extent = xfs_bmap_is_written_extent(irec); struct xfs_trans *tp; - unsigned int resblks; - struct xfs_bmbt_irec uirec; - xfs_filblks_t rlen; - xfs_filblks_t unmap_len; xfs_off_t newlen; - int64_t qres; + int64_t qres, qdelta; + unsigned int resblks; + bool smap_real; + bool dmap_written = xfs_bmap_is_written_extent(dmap); + int nimaps; int error;

- unmap_len = irec->br_startoff + irec->br_blockcount - destoff; - trace_xfs_reflink_punch_range(ip, destoff, unmap_len); - - /* No reflinking if we're low on space */ - if (real_extent) { - error = xfs_reflink_ag_has_free_space(mp, - XFS_FSB_TO_AGNO(mp, irec->br_startblock)); - if (error) - goto out; - } - /* Start a rolling transaction to switch the mappings */ - resblks = XFS_EXTENTADD_SPACE_RES(ip->i_mount, XFS_DATA_FORK); + resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); if (error) goto out; @@ -1029,92 +1016,121 @@ xfs_reflink_remap_extent( xfs_trans_ijoin(tp, ip, 0);

/* - * Reserve quota for this operation. We don't know if the first unmap - * in the dest file will cause a bmap btree split, so we always reserve - * at least enough blocks for that split. If the extent being mapped - * in is written, we need to reserve quota for that too. + * Read what's currently mapped in the destination file into smap. + * If smap isn't a hole, we will have to remove it before we can add + * dmap to the destination file. */ - qres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); - if (real_extent) - qres += irec->br_blockcount; - error = xfs_trans_reserve_quota_nblks(tp, ip, qres, 0, - XFS_QMOPT_RES_REGBLKS); + nimaps = 1; + error = xfs_bmapi_read(ip, dmap->br_startoff, dmap->br_blockcount, + &smap, &nimaps, 0); if (error) goto out_cancel; + ASSERT(nimaps == 1 && smap.br_startoff == dmap->br_startoff); + smap_real = xfs_bmap_is_real_extent(&smap);

- trace_xfs_reflink_remap(ip, irec->br_startoff, - irec->br_blockcount, irec->br_startblock); + /* + * We can only remap as many blocks as the smaller of the two extent + * maps, because we can only remap one extent at a time. + */ + dmap->br_blockcount = min(dmap->br_blockcount, smap.br_blockcount); + ASSERT(dmap->br_blockcount == smap.br_blockcount);

- /* Unmap the old blocks in the data fork. */ - rlen = unmap_len; - while (rlen) { - ASSERT(tp->t_firstblock == NULLFSBLOCK); - error = __xfs_bunmapi(tp, ip, destoff, &rlen, 0, 1); + trace_xfs_reflink_remap_extent_dest(ip, &smap); + + /* No reflinking if the AG of the dest mapping is low on space. */ + if (dmap_written) { + error = xfs_reflink_ag_has_free_space(mp, + XFS_FSB_TO_AGNO(mp, dmap->br_startblock)); if (error) goto out_cancel; + }

+ /* + * Compute quota reservation if we think the quota block counter for + * this file could increase. + * + * We start by reserving enough blocks to handle a bmbt split. + * + * If we are mapping a written extent into the file, we need to have + * enough quota block count reservation to handle the blocks in that + * extent. + * + * Note that if we're replacing a delalloc reservation with a written + * extent, we have to take the full quota reservation because removing + * the delalloc reservation gives the block count back to the quota + * count. This is suboptimal, but the VFS flushed the dest range + * before we started. That should have removed all the delalloc + * reservations, but we code defensively. + */ + qdelta = 0; + qres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); + if (dmap_written) + qres += dmap->br_blockcount; + error = xfs_trans_reserve_quota_nblks(tp, ip, qres, 0, + XFS_QMOPT_RES_REGBLKS); + if (error) + goto out_cancel; + + if (smap_real) { /* - * Trim the extent to whatever got unmapped. - * Remember, bunmapi works backwards. + * If the extent we're unmapping is backed by storage (written + * or not), unmap the extent and drop its refcount. */ - uirec.br_startblock = irec->br_startblock + rlen; - uirec.br_startoff = irec->br_startoff + rlen; - uirec.br_blockcount = unmap_len - rlen; - uirec.br_state = irec->br_state; - unmap_len = rlen; - - /* If this isn't a real mapping, we're done. */ - if (!real_extent || uirec.br_blockcount == 0) - goto next_extent; - - trace_xfs_reflink_remap(ip, uirec.br_startoff, - uirec.br_blockcount, uirec.br_startblock); + xfs_bmap_unmap_extent(tp, ip, &smap); + xfs_refcount_decrease_extent(tp, &smap); + qdelta -= smap.br_blockcount; + } else if (smap.br_startblock == DELAYSTARTBLOCK) { + xfs_filblks_t len = smap.br_blockcount;

- /* Update the refcount tree */ - xfs_refcount_increase_extent(tp, &uirec); - - /* Map the new blocks into the data fork. */ - xfs_bmap_map_extent(tp, ip, &uirec); + /* + * If the extent we're unmapping is a delalloc reservation, + * we can use the regular bunmapi function to release the + * incore state. Dropping the delalloc reservation takes care + * of the quota reservation for us. + */ + error = __xfs_bunmapi(NULL, ip, smap.br_startoff, &len, 0, 1); + if (error) + goto out_cancel; + ASSERT(len == 0); + }

- /* Update quota accounting. */ - xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, - uirec.br_blockcount); + /* + * If the extent we're sharing is backed by written storage, increase + * its refcount and map it into the file. + */ + if (dmap_written) { + xfs_refcount_increase_extent(tp, dmap); + xfs_bmap_map_extent(tp, ip, dmap); + qdelta += dmap->br_blockcount; + }

- /* Update dest isize if needed. */ - newlen = XFS_FSB_TO_B(mp, - uirec.br_startoff + uirec.br_blockcount); - newlen = min_t(xfs_off_t, newlen, new_isize); - if (newlen > i_size_read(VFS_I(ip))) { - trace_xfs_reflink_update_inode_size(ip, newlen); - i_size_write(VFS_I(ip), newlen); - ip->i_d.di_size = newlen; - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - } + xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, qdelta);

-next_extent: - /* Process all the deferred stuff. */ - error = xfs_defer_finish(&tp); - if (error) - goto out_cancel; + /* Update dest isize if needed. */ + newlen = XFS_FSB_TO_B(mp, dmap->br_startoff + dmap->br_blockcount); + newlen = min_t(xfs_off_t, newlen, new_isize); + if (newlen > i_size_read(VFS_I(ip))) { + trace_xfs_reflink_update_inode_size(ip, newlen); + i_size_write(VFS_I(ip), newlen); + ip->i_d.di_size = newlen; + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); }

+ /* Commit everything and unlock. */ error = xfs_trans_commit(tp); - xfs_iunlock(ip, XFS_ILOCK_EXCL); - if (error) - goto out; - return 0; + goto out_unlock;

out_cancel: xfs_trans_cancel(tp); +out_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); out: - trace_xfs_reflink_remap_extent_error(ip, error, _RET_IP_); + if (error) + trace_xfs_reflink_remap_extent_error(ip, error, _RET_IP_); return error; }

-/* - * Iteratively remap one file's extents (and holes) to another's. - */ +/* Remap a range of one file to the other. */ int xfs_reflink_remap_blocks( struct xfs_inode *src, @@ -1125,25 +1141,22 @@ xfs_reflink_remap_blocks( loff_t *remapped) { struct xfs_bmbt_irec imap; - xfs_fileoff_t srcoff; - xfs_fileoff_t destoff; + struct xfs_mount *mp = src->i_mount; + xfs_fileoff_t srcoff = XFS_B_TO_FSBT(mp, pos_in); + xfs_fileoff_t destoff = XFS_B_TO_FSBT(mp, pos_out); xfs_filblks_t len; - xfs_filblks_t range_len; xfs_filblks_t remapped_len = 0; xfs_off_t new_isize = pos_out + remap_len; int nimaps; int error = 0;

- destoff = XFS_B_TO_FSBT(src->i_mount, pos_out); - srcoff = XFS_B_TO_FSBT(src->i_mount, pos_in); - len = XFS_B_TO_FSB(src->i_mount, remap_len); + len = min_t(xfs_filblks_t, XFS_B_TO_FSB(mp, remap_len), + XFS_MAX_FILEOFF);

- /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ - while (len) { - uint lock_mode; + trace_xfs_reflink_remap_blocks(src, srcoff, len, dest, destoff);

- trace_xfs_reflink_remap_blocks_loop(src, srcoff, len, - dest, destoff); + while (len > 0) { + unsigned int lock_mode;

/* Read extent from the source file */ nimaps = 1; @@ -1152,18 +1165,25 @@ xfs_reflink_remap_blocks( xfs_iunlock(src, lock_mode); if (error) break; - ASSERT(nimaps == 1); - - trace_xfs_reflink_remap_imap(src, srcoff, len, XFS_DATA_FORK, - &imap); + /* + * The caller supposedly flushed all dirty pages in the source + * file range, which means that writeback should have allocated + * or deleted all delalloc reservations in that range. If we + * find one, that's a good sign that something is seriously + * wrong here. + */ + ASSERT(nimaps == 1 && imap.br_startoff == srcoff); + if (imap.br_startblock == DELAYSTARTBLOCK) { + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + error = -EFSCORRUPTED; + break; + }

- /* Translate imap into the destination file. */ - range_len = imap.br_startoff + imap.br_blockcount - srcoff; - imap.br_startoff += destoff - srcoff; + trace_xfs_reflink_remap_extent_src(src, &imap);

- /* Clear dest from destoff to the end of imap and map it in. */ - error = xfs_reflink_remap_extent(dest, &imap, destoff, - new_isize); + /* Remap into the destination file at the given offset. */ + imap.br_startoff = destoff; + error = xfs_reflink_remap_extent(dest, &imap, new_isize); if (error) break;

@@ -1173,10 +1193,10 @@ xfs_reflink_remap_blocks( }

/* Advance drange/srange */ - srcoff += range_len; - destoff += range_len; - len -= range_len; - remapped_len += range_len; + srcoff += imap.br_blockcount; + destoff += imap.br_blockcount; + len -= imap.br_blockcount; + remapped_len += imap.br_blockcount; }

if (error) diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index b5d4ca60145a..f94908125e8f 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -3078,8 +3078,7 @@ DEFINE_EVENT(xfs_inode_irec_class, name, \ DEFINE_INODE_EVENT(xfs_reflink_set_inode_flag); DEFINE_INODE_EVENT(xfs_reflink_unset_inode_flag); DEFINE_ITRUNC_EVENT(xfs_reflink_update_inode_size); -DEFINE_IMAP_EVENT(xfs_reflink_remap_imap); -TRACE_EVENT(xfs_reflink_remap_blocks_loop, +TRACE_EVENT(xfs_reflink_remap_blocks, TP_PROTO(struct xfs_inode *src, xfs_fileoff_t soffset, xfs_filblks_t len, struct xfs_inode *dest, xfs_fileoff_t doffset), @@ -3110,59 +3109,14 @@ TRACE_EVENT(xfs_reflink_remap_blocks_loop, __entry->dest_ino, __entry->dest_lblk) ); -TRACE_EVENT(xfs_reflink_punch_range, - TP_PROTO(struct xfs_inode *ip, xfs_fileoff_t lblk, - xfs_extlen_t len), - TP_ARGS(ip, lblk, len), - TP_STRUCT__entry( - __field(dev_t, dev) - __field(xfs_ino_t, ino) - __field(xfs_fileoff_t, lblk) - __field(xfs_extlen_t, len) - ), - TP_fast_assign( - __entry->dev = VFS_I(ip)->i_sb->s_dev; - __entry->ino = ip->i_ino; - __entry->lblk = lblk; - __entry->len = len; - ), - TP_printk("dev %d:%d ino 0x%llx lblk 0x%llx len 0x%x", - MAJOR(__entry->dev), MINOR(__entry->dev), - __entry->ino, - __entry->lblk, - __entry->len) -); -TRACE_EVENT(xfs_reflink_remap, - TP_PROTO(struct xfs_inode *ip, xfs_fileoff_t lblk, - xfs_extlen_t len, xfs_fsblock_t new_pblk), - TP_ARGS(ip, lblk, len, new_pblk), - TP_STRUCT__entry( - __field(dev_t, dev) - __field(xfs_ino_t, ino) - __field(xfs_fileoff_t, lblk) - __field(xfs_extlen_t, len) - __field(xfs_fsblock_t, new_pblk) - ), - TP_fast_assign( - __entry->dev = VFS_I(ip)->i_sb->s_dev; - __entry->ino = ip->i_ino; - __entry->lblk = lblk; - __entry->len = len; - __entry->new_pblk = new_pblk; - ), - TP_printk("dev %d:%d ino 0x%llx lblk 0x%llx len 0x%x new_pblk %llu", - MAJOR(__entry->dev), MINOR(__entry->dev), - __entry->ino, - __entry->lblk, - __entry->len, - __entry->new_pblk) -); DEFINE_DOUBLE_IO_EVENT(xfs_reflink_remap_range); DEFINE_INODE_ERROR_EVENT(xfs_reflink_remap_range_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_set_inode_flag_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_update_inode_size_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_remap_blocks_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_remap_extent_error); +DEFINE_INODE_IREC_EVENT(xfs_reflink_remap_extent_src); +DEFINE_INODE_IREC_EVENT(xfs_reflink_remap_extent_dest);

/* dedupe tracepoints */ DEFINE_DOUBLE_IO_EVENT(xfs_reflink_compare_extents);

From: Eric Sandeen sandeen@redhat.com

commit 4750a171c3290f9bbebca16c6372db723a4cfa3b upstream.

[ For 5.4.y, SB_I_VERSION should be set in xfs_fs_remount() ]

The MS_I_VERSION mount flag is exposed via the VFS, as documented in the mount manpages etc; see the iversion and noiversion mount options in mount(8).

As a result, mount -o remount looks for this option in /proc/mounts and will only send the I_VERSION flag back in during remount it it is present. Since it's not there, a remount will /remove/ the I_VERSION flag at the vfs level, and iversion functionality is lost.

xfs v5 superblocks intend to always have i_version enabled; it is set as a default at mount time, but is lost during remount for the reasons above.

The generic fix would be to expose this documented option in /proc/mounts, but since that was rejected, fix it up again in the xfs remount path instead, so that at least xfs won't suffer from this misbehavior.

Signed-off-by: Eric Sandeen sandeen@redhat.com Reviewed-by: Dave Chinner dchinner@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Darrick J. Wong darrick.wong@oracle.com Acked-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Chandan Babu R chandan.babu@oracle.com --- fs/xfs/xfs_super.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 2429acbfb132..f1407900aeef 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1228,6 +1228,10 @@ xfs_fs_remount( char *p; int error;

+ /* version 5 superblocks always support version counters. */ + if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5) + *flags |= SB_I_VERSION; + /* First, check for complete junk; i.e. invalid options */ error = xfs_test_remount_options(sb, options); if (error)