6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dave Chinner dchinner@redhat.com
[ Upstream commit b742d7b4f0e03df25c2a772adcded35044b625ca ]
[ 6.1: resolved conflict in xfs_extfree_item.c ]
Btrees that aren't freespace management trees use the normal extent allocation and freeing routines for their blocks. Hence when a btree block is freed, a direct call to xfs_free_extent() is made and the extent is immediately freed. This puts the entire free space management btrees under this path, so we are stacking btrees on btrees in the call stack. The inobt, finobt and refcount btrees all do this.
However, the bmap btree does not do this - it calls xfs_free_extent_later() to defer the extent free operation via an XEFI and hence it gets processed in deferred operation processing during the commit of the primary transaction (i.e. via intent chaining).
We need to change xfs_free_extent() to behave in a non-blocking manner so that we can avoid deadlocks with busy extents near ENOSPC in transactions that free multiple extents. Inserting or removing a record from a btree can cause a multi-level tree merge operation and that will free multiple blocks from the btree in a single transaction. i.e. we can call xfs_free_extent() multiple times, and hence the btree manipulation transaction is vulnerable to this busy extent deadlock vector.
To fix this, convert all the remaining callers of xfs_free_extent() to use xfs_free_extent_later() to queue XEFIs and hence defer processing of the extent frees to a context that can be safely restarted if a deadlock condition is detected.
Signed-off-by: Dave Chinner dchinner@redhat.com Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Chandan Babu R chandan.babu@oracle.com Signed-off-by: Leah Rumancik leah.rumancik@gmail.com Acked-by: "Darrick J. Wong" djwong@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/xfs/libxfs/xfs_ag.c | 2 +- fs/xfs/libxfs/xfs_alloc.c | 4 ++++ fs/xfs/libxfs/xfs_alloc.h | 8 +++++--- fs/xfs/libxfs/xfs_bmap.c | 8 +++++--- fs/xfs/libxfs/xfs_bmap_btree.c | 3 ++- fs/xfs/libxfs/xfs_ialloc.c | 8 ++++---- fs/xfs/libxfs/xfs_ialloc_btree.c | 3 +-- fs/xfs/libxfs/xfs_refcount.c | 9 ++++++--- fs/xfs/libxfs/xfs_refcount_btree.c | 8 +------- fs/xfs/xfs_extfree_item.c | 3 ++- fs/xfs/xfs_reflink.c | 3 ++- 11 files changed, 33 insertions(+), 26 deletions(-)
--- a/fs/xfs/libxfs/xfs_ag.c +++ b/fs/xfs/libxfs/xfs_ag.c @@ -907,7 +907,7 @@ xfs_ag_shrink_space( goto resv_err;
err2 = __xfs_free_extent_later(*tpp, args.fsbno, delta, NULL, - true); + XFS_AG_RESV_NONE, true); if (err2) goto resv_err;
--- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -2507,6 +2507,7 @@ xfs_defer_agfl_block( xefi->xefi_startblock = fsbno; xefi->xefi_blockcount = 1; xefi->xefi_owner = oinfo->oi_owner; + xefi->xefi_agresv = XFS_AG_RESV_AGFL;
trace_xfs_agfl_free_defer(mp, agno, 0, agbno, 1);
@@ -2524,6 +2525,7 @@ __xfs_free_extent_later( xfs_fsblock_t bno, xfs_filblks_t len, const struct xfs_owner_info *oinfo, + enum xfs_ag_resv_type type, bool skip_discard) { struct xfs_extent_free_item *xefi; @@ -2544,6 +2546,7 @@ __xfs_free_extent_later( ASSERT(agbno + len <= mp->m_sb.sb_agblocks); #endif ASSERT(xfs_extfree_item_cache != NULL); + ASSERT(type != XFS_AG_RESV_AGFL);
if (XFS_IS_CORRUPT(mp, !xfs_verify_fsbext(mp, bno, len))) return -EFSCORRUPTED; @@ -2552,6 +2555,7 @@ __xfs_free_extent_later( GFP_KERNEL | __GFP_NOFAIL); xefi->xefi_startblock = bno; xefi->xefi_blockcount = (xfs_extlen_t)len; + xefi->xefi_agresv = type; if (skip_discard) xefi->xefi_flags |= XFS_EFI_SKIP_DISCARD; if (oinfo) { --- a/fs/xfs/libxfs/xfs_alloc.h +++ b/fs/xfs/libxfs/xfs_alloc.h @@ -215,7 +215,7 @@ xfs_buf_to_agfl_bno(
int __xfs_free_extent_later(struct xfs_trans *tp, xfs_fsblock_t bno, xfs_filblks_t len, const struct xfs_owner_info *oinfo, - bool skip_discard); + enum xfs_ag_resv_type type, bool skip_discard);
/* * List of extents to be free "later". @@ -227,6 +227,7 @@ struct xfs_extent_free_item { xfs_fsblock_t xefi_startblock;/* starting fs block number */ xfs_extlen_t xefi_blockcount;/* number of blocks in extent */ unsigned int xefi_flags; + enum xfs_ag_resv_type xefi_agresv; };
#define XFS_EFI_SKIP_DISCARD (1U << 0) /* don't issue discard */ @@ -238,9 +239,10 @@ xfs_free_extent_later( struct xfs_trans *tp, xfs_fsblock_t bno, xfs_filblks_t len, - const struct xfs_owner_info *oinfo) + const struct xfs_owner_info *oinfo, + enum xfs_ag_resv_type type) { - return __xfs_free_extent_later(tp, bno, len, oinfo, false); + return __xfs_free_extent_later(tp, bno, len, oinfo, type, false); }
--- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -574,7 +574,8 @@ xfs_bmap_btree_to_extents( return error;
xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork); - error = xfs_free_extent_later(cur->bc_tp, cbno, 1, &oinfo); + error = xfs_free_extent_later(cur->bc_tp, cbno, 1, &oinfo, + XFS_AG_RESV_NONE); if (error) return error;
@@ -5208,8 +5209,9 @@ xfs_bmap_del_extent_real( } else { error = __xfs_free_extent_later(tp, del->br_startblock, del->br_blockcount, NULL, - (bflags & XFS_BMAPI_NODISCARD) || - del->br_state == XFS_EXT_UNWRITTEN); + XFS_AG_RESV_NONE, + ((bflags & XFS_BMAPI_NODISCARD) || + del->br_state == XFS_EXT_UNWRITTEN)); if (error) goto done; } --- a/fs/xfs/libxfs/xfs_bmap_btree.c +++ b/fs/xfs/libxfs/xfs_bmap_btree.c @@ -288,7 +288,8 @@ xfs_bmbt_free_block( int error;
xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, cur->bc_ino.whichfork); - error = xfs_free_extent_later(cur->bc_tp, fsbno, 1, &oinfo); + error = xfs_free_extent_later(cur->bc_tp, fsbno, 1, &oinfo, + XFS_AG_RESV_NONE); if (error) return error;
--- a/fs/xfs/libxfs/xfs_ialloc.c +++ b/fs/xfs/libxfs/xfs_ialloc.c @@ -1846,8 +1846,8 @@ xfs_difree_inode_chunk( /* not sparse, calculate extent info directly */ return xfs_free_extent_later(tp, XFS_AGB_TO_FSB(mp, agno, sagbno), - M_IGEO(mp)->ialloc_blks, - &XFS_RMAP_OINFO_INODES); + M_IGEO(mp)->ialloc_blks, &XFS_RMAP_OINFO_INODES, + XFS_AG_RESV_NONE); }
/* holemask is only 16-bits (fits in an unsigned long) */ @@ -1892,8 +1892,8 @@ xfs_difree_inode_chunk( ASSERT(agbno % mp->m_sb.sb_spino_align == 0); ASSERT(contigblk % mp->m_sb.sb_spino_align == 0); error = xfs_free_extent_later(tp, - XFS_AGB_TO_FSB(mp, agno, agbno), - contigblk, &XFS_RMAP_OINFO_INODES); + XFS_AGB_TO_FSB(mp, agno, agbno), contigblk, + &XFS_RMAP_OINFO_INODES, XFS_AG_RESV_NONE); if (error) return error;
--- a/fs/xfs/libxfs/xfs_ialloc_btree.c +++ b/fs/xfs/libxfs/xfs_ialloc_btree.c @@ -160,8 +160,7 @@ __xfs_inobt_free_block(
xfs_inobt_mod_blockcount(cur, -1); fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, xfs_buf_daddr(bp)); - return xfs_free_extent(cur->bc_tp, cur->bc_ag.pag, - XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno), 1, + return xfs_free_extent_later(cur->bc_tp, fsbno, 1, &XFS_RMAP_OINFO_INOBT, resv); }
--- a/fs/xfs/libxfs/xfs_refcount.c +++ b/fs/xfs/libxfs/xfs_refcount.c @@ -1130,7 +1130,8 @@ xfs_refcount_adjust_extents( cur->bc_ag.pag->pag_agno, tmp.rc_startblock); error = xfs_free_extent_later(cur->bc_tp, fsbno, - tmp.rc_blockcount, NULL); + tmp.rc_blockcount, NULL, + XFS_AG_RESV_NONE); if (error) goto out_error; } @@ -1191,7 +1192,8 @@ xfs_refcount_adjust_extents( cur->bc_ag.pag->pag_agno, ext.rc_startblock); error = xfs_free_extent_later(cur->bc_tp, fsbno, - ext.rc_blockcount, NULL); + ext.rc_blockcount, NULL, + XFS_AG_RESV_NONE); if (error) goto out_error; } @@ -1963,7 +1965,8 @@ xfs_refcount_recover_cow_leftovers(
/* Free the block. */ error = xfs_free_extent_later(tp, fsb, - rr->rr_rrec.rc_blockcount, NULL); + rr->rr_rrec.rc_blockcount, NULL, + XFS_AG_RESV_NONE); if (error) goto out_trans;
--- a/fs/xfs/libxfs/xfs_refcount_btree.c +++ b/fs/xfs/libxfs/xfs_refcount_btree.c @@ -106,19 +106,13 @@ xfs_refcountbt_free_block( struct xfs_buf *agbp = cur->bc_ag.agbp; struct xfs_agf *agf = agbp->b_addr; xfs_fsblock_t fsbno = XFS_DADDR_TO_FSB(mp, xfs_buf_daddr(bp)); - int error;
trace_xfs_refcountbt_free_block(cur->bc_mp, cur->bc_ag.pag->pag_agno, XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno), 1); be32_add_cpu(&agf->agf_refcount_blocks, -1); xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_REFCOUNT_BLOCKS); - error = xfs_free_extent(cur->bc_tp, cur->bc_ag.pag, - XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno), 1, + return xfs_free_extent_later(cur->bc_tp, fsbno, 1, &XFS_RMAP_OINFO_REFC, XFS_AG_RESV_METADATA); - if (error) - return error; - - return error; }
STATIC int --- a/fs/xfs/xfs_extfree_item.c +++ b/fs/xfs/xfs_extfree_item.c @@ -369,7 +369,7 @@ xfs_trans_free_extent(
pag = xfs_perag_get(mp, agno); error = __xfs_free_extent(tp, pag, agbno, xefi->xefi_blockcount, - &oinfo, XFS_AG_RESV_NONE, + &oinfo, xefi->xefi_agresv, xefi->xefi_flags & XFS_EFI_SKIP_DISCARD); xfs_perag_put(pag);
@@ -628,6 +628,7 @@ xfs_efi_item_recover( for (i = 0; i < efip->efi_format.efi_nextents; i++) { struct xfs_extent_free_item fake = { .xefi_owner = XFS_RMAP_OWN_UNKNOWN, + .xefi_agresv = XFS_AG_RESV_NONE, }; struct xfs_extent *extp;
--- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -619,7 +619,8 @@ xfs_reflink_cancel_cow_blocks( del.br_blockcount);
error = xfs_free_extent_later(*tpp, del.br_startblock, - del.br_blockcount, NULL); + del.br_blockcount, NULL, + XFS_AG_RESV_NONE); if (error) break;