From 52c732eee78b47ac2eb828b1c7fa611cd37b0090 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 17 Oct 2017 21:37:33 -0700 Subject: [PATCH] xfs: refactor btree block header checking functions Refactor the btree block header checks to have an internal function that returns the address of the failing check without logging errors. The scrubber will call the internal function, while the external version will maintain the current logging behavior. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner --- fs/xfs/libxfs/xfs_btree.c | 164 +++++++++++++++++++++++--------------- fs/xfs/libxfs/xfs_btree.h | 8 ++ fs/xfs/libxfs/xfs_types.h | 6 ++ fs/xfs/xfs_linux.h | 7 ++ 4 files changed, 119 insertions(+), 66 deletions(-) diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index ae19f242c237..8bb20e1cf57b 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -63,44 +63,63 @@ xfs_btree_magic( return magic; } -STATIC int /* error (0 or EFSCORRUPTED) */ -xfs_btree_check_lblock( - struct xfs_btree_cur *cur, /* btree cursor */ - struct xfs_btree_block *block, /* btree long form block pointer */ - int level, /* level of the btree block */ - struct xfs_buf *bp) /* buffer for block, if any */ +/* + * Check a long btree block header. Return the address of the failing check, + * or NULL if everything is ok. + */ +xfs_failaddr_t +__xfs_btree_check_lblock( + struct xfs_btree_cur *cur, + struct xfs_btree_block *block, + int level, + struct xfs_buf *bp) { - int lblock_ok = 1; /* block passes checks */ - struct xfs_mount *mp; /* file system mount point */ + struct xfs_mount *mp = cur->bc_mp; xfs_btnum_t btnum = cur->bc_btnum; - int crc; - - mp = cur->bc_mp; - crc = xfs_sb_version_hascrc(&mp->m_sb); + int crc = xfs_sb_version_hascrc(&mp->m_sb); if (crc) { - lblock_ok = lblock_ok && - uuid_equal(&block->bb_u.l.bb_uuid, - &mp->m_sb.sb_meta_uuid) && - block->bb_u.l.bb_blkno == cpu_to_be64( - bp ? bp->b_bn : XFS_BUF_DADDR_NULL); + if (!uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid)) + return __this_address; + if (block->bb_u.l.bb_blkno != + cpu_to_be64(bp ? bp->b_bn : XFS_BUF_DADDR_NULL)) + return __this_address; + if (block->bb_u.l.bb_pad != cpu_to_be32(0)) + return __this_address; } - lblock_ok = lblock_ok && - be32_to_cpu(block->bb_magic) == xfs_btree_magic(crc, btnum) && - be16_to_cpu(block->bb_level) == level && - be16_to_cpu(block->bb_numrecs) <= - cur->bc_ops->get_maxrecs(cur, level) && - block->bb_u.l.bb_leftsib && - (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK) || - XFS_FSB_SANITY_CHECK(mp, - be64_to_cpu(block->bb_u.l.bb_leftsib))) && - block->bb_u.l.bb_rightsib && - (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK) || - XFS_FSB_SANITY_CHECK(mp, - be64_to_cpu(block->bb_u.l.bb_rightsib))); + if (be32_to_cpu(block->bb_magic) != xfs_btree_magic(crc, btnum)) + return __this_address; + if (be16_to_cpu(block->bb_level) != level) + return __this_address; + if (be16_to_cpu(block->bb_numrecs) > + cur->bc_ops->get_maxrecs(cur, level)) + return __this_address; + if (block->bb_u.l.bb_leftsib != cpu_to_be64(NULLFSBLOCK) && + !xfs_btree_check_lptr(cur, be64_to_cpu(block->bb_u.l.bb_leftsib), + level + 1)) + return __this_address; + if (block->bb_u.l.bb_rightsib != cpu_to_be64(NULLFSBLOCK) && + !xfs_btree_check_lptr(cur, be64_to_cpu(block->bb_u.l.bb_rightsib), + level + 1)) + return __this_address; - if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp, + return NULL; +} + +/* Check a long btree block header. */ +int +xfs_btree_check_lblock( + struct xfs_btree_cur *cur, + struct xfs_btree_block *block, + int level, + struct xfs_buf *bp) +{ + struct xfs_mount *mp = cur->bc_mp; + xfs_failaddr_t fa; + + fa = __xfs_btree_check_lblock(cur, block, level, bp); + if (unlikely(XFS_TEST_ERROR(fa != NULL, mp, XFS_ERRTAG_BTREE_CHECK_LBLOCK))) { if (bp) trace_xfs_btree_corrupt(bp, _RET_IP_); @@ -110,48 +129,61 @@ xfs_btree_check_lblock( return 0; } -STATIC int /* error (0 or EFSCORRUPTED) */ -xfs_btree_check_sblock( - struct xfs_btree_cur *cur, /* btree cursor */ - struct xfs_btree_block *block, /* btree short form block pointer */ - int level, /* level of the btree block */ - struct xfs_buf *bp) /* buffer containing block */ +/* + * Check a short btree block header. Return the address of the failing check, + * or NULL if everything is ok. + */ +xfs_failaddr_t +__xfs_btree_check_sblock( + struct xfs_btree_cur *cur, + struct xfs_btree_block *block, + int level, + struct xfs_buf *bp) { - struct xfs_mount *mp; /* file system mount point */ - struct xfs_buf *agbp; /* buffer for ag. freespace struct */ - struct xfs_agf *agf; /* ag. freespace structure */ - xfs_agblock_t agflen; /* native ag. freespace length */ - int sblock_ok = 1; /* block passes checks */ + struct xfs_mount *mp = cur->bc_mp; xfs_btnum_t btnum = cur->bc_btnum; - int crc; - - mp = cur->bc_mp; - crc = xfs_sb_version_hascrc(&mp->m_sb); - agbp = cur->bc_private.a.agbp; - agf = XFS_BUF_TO_AGF(agbp); - agflen = be32_to_cpu(agf->agf_length); + int crc = xfs_sb_version_hascrc(&mp->m_sb); if (crc) { - sblock_ok = sblock_ok && - uuid_equal(&block->bb_u.s.bb_uuid, - &mp->m_sb.sb_meta_uuid) && - block->bb_u.s.bb_blkno == cpu_to_be64( - bp ? bp->b_bn : XFS_BUF_DADDR_NULL); + if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid)) + return __this_address; + if (block->bb_u.s.bb_blkno != + cpu_to_be64(bp ? bp->b_bn : XFS_BUF_DADDR_NULL)) + return __this_address; } - sblock_ok = sblock_ok && - be32_to_cpu(block->bb_magic) == xfs_btree_magic(crc, btnum) && - be16_to_cpu(block->bb_level) == level && - be16_to_cpu(block->bb_numrecs) <= - cur->bc_ops->get_maxrecs(cur, level) && - (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) || - be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) && - block->bb_u.s.bb_leftsib && - (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) || - be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) && - block->bb_u.s.bb_rightsib; + if (be32_to_cpu(block->bb_magic) != xfs_btree_magic(crc, btnum)) + return __this_address; + if (be16_to_cpu(block->bb_level) != level) + return __this_address; + if (be16_to_cpu(block->bb_numrecs) > + cur->bc_ops->get_maxrecs(cur, level)) + return __this_address; + if (block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK) && + !xfs_btree_check_sptr(cur, be32_to_cpu(block->bb_u.s.bb_leftsib), + level + 1)) + return __this_address; + if (block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK) && + !xfs_btree_check_sptr(cur, be32_to_cpu(block->bb_u.s.bb_rightsib), + level + 1)) + return __this_address; - if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp, + return NULL; +} + +/* Check a short btree block header. */ +STATIC int +xfs_btree_check_sblock( + struct xfs_btree_cur *cur, + struct xfs_btree_block *block, + int level, + struct xfs_buf *bp) +{ + struct xfs_mount *mp = cur->bc_mp; + xfs_failaddr_t fa; + + fa = __xfs_btree_check_sblock(cur, block, level, bp); + if (unlikely(XFS_TEST_ERROR(fa != NULL, mp, XFS_ERRTAG_BTREE_CHECK_SBLOCK))) { if (bp) trace_xfs_btree_corrupt(bp, _RET_IP_); diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h index 8f52eda8eb82..3f8001de2493 100644 --- a/fs/xfs/libxfs/xfs_btree.h +++ b/fs/xfs/libxfs/xfs_btree.h @@ -255,6 +255,14 @@ typedef struct xfs_btree_cur */ #define XFS_BUF_TO_BLOCK(bp) ((struct xfs_btree_block *)((bp)->b_addr)) +/* + * Internal long and short btree block checks. They return NULL if the + * block is ok or the address of the failed check otherwise. + */ +xfs_failaddr_t __xfs_btree_check_lblock(struct xfs_btree_cur *cur, + struct xfs_btree_block *block, int level, struct xfs_buf *bp); +xfs_failaddr_t __xfs_btree_check_sblock(struct xfs_btree_cur *cur, + struct xfs_btree_block *block, int level, struct xfs_buf *bp); /* * Check that block header is ok. diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h index 0220159bd463..f04dbfb2f50d 100644 --- a/fs/xfs/libxfs/xfs_types.h +++ b/fs/xfs/libxfs/xfs_types.h @@ -47,6 +47,12 @@ typedef uint64_t xfs_filblks_t; /* number of blocks in a file */ typedef int64_t xfs_srtblock_t; /* signed version of xfs_rtblock_t */ typedef int64_t xfs_sfiloff_t; /* signed block number in a file */ +/* + * New verifiers will return the instruction address of the failing check. + * NULL means everything is ok. + */ +typedef void * xfs_failaddr_t; + /* * Null values for the types. */ diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index dcd1292664b3..00a5efeec496 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -142,6 +142,13 @@ typedef __u32 xfs_nlink_t; #define SYNCHRONIZE() barrier() #define __return_address __builtin_return_address(0) +/* + * Return the address of a label. Use barrier() so that the optimizer + * won't reorder code to refactor the error jumpouts into a single + * return, which throws off the reported address. + */ +#define __this_address ({ __label__ __here; __here: barrier(); &&__here; }) + #define XFS_PROJID_DEFAULT 0 #define MIN(a,b) (min(a,b))