From df50b677c079b9f0a5637f9e2c1ab9e07ed0823e Mon Sep 17 00:00:00 2001 From: mm Date: Thu, 3 Jun 2010 11:08:46 +0000 Subject: Fix freeing space after deleting large files with holes. OpenSolaris onnv revision: 9950:78fc41aa9bc5 Approved by: pjd, delphij (mentor) Obtained from: OpenSolaris (Bug ID 6792701) MFC after: 3 days --- .../contrib/opensolaris/uts/common/fs/zfs/dmu.c | 65 ++++++++++------------ 1 file changed, 30 insertions(+), 35 deletions(-) (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c') diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c index 55501e9..1152781 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c @@ -371,56 +371,51 @@ dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) dnode_rele(dn, FTAG); } +/* + * Get the next "chunk" of file data to free. We traverse the file from + * the end so that the file gets shorter over time (if we crashes in the + * middle, this will leave us in a better state). We find allocated file + * data by simply searching the allocated level 1 indirects. + */ static int -get_next_chunk(dnode_t *dn, uint64_t *offset, uint64_t limit) +get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit) { - uint64_t len = *offset - limit; - uint64_t chunk_len = dn->dn_datablksz * DMU_MAX_DELETEBLKCNT; - uint64_t subchunk = + uint64_t len = *start - limit; + uint64_t blkcnt = 0; + uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1)); + uint64_t iblkrange = dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); - ASSERT(limit <= *offset); + ASSERT(limit <= *start); - if (len <= chunk_len) { - *offset = limit; + if (len <= iblkrange * maxblks) { + *start = limit; return (0); } + ASSERT(ISP2(iblkrange)); - ASSERT(ISP2(subchunk)); - - while (*offset > limit) { - uint64_t initial_offset = P2ROUNDUP(*offset, subchunk); - uint64_t delta; + while (*start > limit && blkcnt < maxblks) { int err; - /* skip over allocated data */ + /* find next allocated L1 indirect */ err = dnode_next_offset(dn, - DNODE_FIND_HOLE|DNODE_FIND_BACKWARDS, offset, 1, 1, 0); - if (err == ESRCH) - *offset = limit; - else if (err) - return (err); + DNODE_FIND_BACKWARDS, start, 2, 1, 0); - ASSERT3U(*offset, <=, initial_offset); - *offset = P2ALIGN(*offset, subchunk); - delta = initial_offset - *offset; - if (delta >= chunk_len) { - *offset += delta - chunk_len; + /* if there are no more, then we are done */ + if (err == ESRCH) { + *start = limit; return (0); - } - chunk_len -= delta; - - /* skip over unallocated data */ - err = dnode_next_offset(dn, - DNODE_FIND_BACKWARDS, offset, 1, 1, 0); - if (err == ESRCH) - *offset = limit; - else if (err) + } else if (err) { return (err); + } + blkcnt += 1; - if (*offset < limit) - *offset = limit; - ASSERT3U(*offset, <, initial_offset); + /* reset offset to end of "next" block back */ + *start = P2ALIGN(*start, iblkrange); + if (*start <= limit) + *start = limit; + else + *start -= 1; } return (0); } -- cgit v1.1