diff options
Diffstat (limited to 'module/zfs/dmu.c')
-rw-r--r-- | module/zfs/dmu.c | 135 |
1 files changed, 63 insertions, 72 deletions
diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c index 1e16b1eb0..1136e1d70 100644 --- a/module/zfs/dmu.c +++ b/module/zfs/dmu.c @@ -568,98 +568,95 @@ dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) * 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. + * + * On input, *start should be the first offset that does not need to be + * freed (e.g. "offset + length"). On return, *start will be the first + * offset that should be freed. */ static int -get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit) +get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum) { - uint64_t len = *start - limit; - uint64_t blkcnt = 0; - uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1)); + uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1); + /* bytes of data covered by a level-1 indirect block */ uint64_t iblkrange = dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); + uint64_t blks; - ASSERT(limit <= *start); + ASSERT3U(minimum, <=, *start); - if (len <= iblkrange * maxblks) { - *start = limit; + if (*start - minimum <= iblkrange * maxblks) { + *start = minimum; return (0); } ASSERT(ISP2(iblkrange)); - while (*start > limit && blkcnt < maxblks) { + for (blks = 0; *start > minimum && blks < maxblks; blks++) { int err; - /* find next allocated L1 indirect */ + /* + * dnode_next_offset(BACKWARDS) will find an allocated L1 + * indirect block at or before the input offset. We must + * decrement *start so that it is at the end of the region + * to search. + */ + (*start)--; err = dnode_next_offset(dn, DNODE_FIND_BACKWARDS, start, 2, 1, 0); - /* if there are no more, then we are done */ + /* if there are no indirect blocks before start, we are done */ if (err == ESRCH) { - *start = limit; - return (0); - } else if (err) { + *start = minimum; + break; + } else if (err != 0) { return (err); } - blkcnt += 1; - /* reset offset to end of "next" block back */ + /* set start to the beginning of this L1 indirect */ *start = P2ALIGN(*start, iblkrange); - if (*start <= limit) - *start = limit; - else - *start -= 1; } + if (*start < minimum) + *start = minimum; return (0); } static int dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, - uint64_t length, boolean_t free_dnode) + uint64_t length) { - dmu_tx_t *tx; - uint64_t object_size, start, end, len; - boolean_t trunc = (length == DMU_OBJECT_END); - int align, err; - - align = 1 << dn->dn_datablkshift; - ASSERT(align > 0); - object_size = align == 1 ? dn->dn_datablksz : - (dn->dn_maxblkid + 1) << dn->dn_datablkshift; - - end = offset + length; - if (trunc || end > object_size) - end = object_size; - if (end <= offset) + uint64_t object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz; + int err; + + if (offset >= object_size) return (0); - length = end - offset; - while (length) { - start = end; - /* assert(offset <= start) */ - err = get_next_chunk(dn, &start, offset); + if (length == DMU_OBJECT_END || offset + length > object_size) + length = object_size - offset; + + while (length != 0) { + uint64_t chunk_end, chunk_begin; + dmu_tx_t *tx; + + chunk_end = chunk_begin = offset + length; + + /* move chunk_begin backwards to the beginning of this chunk */ + err = get_next_chunk(dn, &chunk_begin, offset); if (err) return (err); - len = trunc ? DMU_OBJECT_END : end - start; + ASSERT3U(chunk_begin, >=, offset); + ASSERT3U(chunk_begin, <=, chunk_end); tx = dmu_tx_create(os); - dmu_tx_hold_free(tx, dn->dn_object, start, len); + dmu_tx_hold_free(tx, dn->dn_object, + chunk_begin, chunk_end - chunk_begin); err = dmu_tx_assign(tx, TXG_WAIT); if (err) { dmu_tx_abort(tx); return (err); } - - dnode_free_range(dn, start, trunc ? -1 : len, tx); - - if (start == 0 && free_dnode) { - ASSERT(trunc); - dnode_free(dn, tx); - } - - length -= end - start; - + dnode_free_range(dn, chunk_begin, chunk_end - chunk_begin, tx); dmu_tx_commit(tx); - end = start; + + length -= chunk_end - chunk_begin; } return (0); } @@ -674,38 +671,32 @@ dmu_free_long_range(objset_t *os, uint64_t object, err = dnode_hold(os, object, FTAG, &dn); if (err != 0) return (err); - err = dmu_free_long_range_impl(os, dn, offset, length, FALSE); + err = dmu_free_long_range_impl(os, dn, offset, length); dnode_rele(dn, FTAG); return (err); } int -dmu_free_object(objset_t *os, uint64_t object) +dmu_free_long_object(objset_t *os, uint64_t object) { - dnode_t *dn; dmu_tx_t *tx; int err; - err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, - FTAG, &dn); + err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END); if (err != 0) return (err); - if (dn->dn_nlevels == 1) { - tx = dmu_tx_create(os); - dmu_tx_hold_bonus(tx, object); - dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END); - err = dmu_tx_assign(tx, TXG_WAIT); - if (err == 0) { - dnode_free_range(dn, 0, DMU_OBJECT_END, tx); - dnode_free(dn, tx); - dmu_tx_commit(tx); - } else { - dmu_tx_abort(tx); - } + + tx = dmu_tx_create(os); + dmu_tx_hold_bonus(tx, object); + dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END); + err = dmu_tx_assign(tx, TXG_WAIT); + if (err == 0) { + err = dmu_object_free(os, object, tx); + dmu_tx_commit(tx); } else { - err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE); + dmu_tx_abort(tx); } - dnode_rele(dn, FTAG); + return (err); } @@ -2042,7 +2033,7 @@ EXPORT_SYMBOL(dmu_buf_rele_array); EXPORT_SYMBOL(dmu_prefetch); EXPORT_SYMBOL(dmu_free_range); EXPORT_SYMBOL(dmu_free_long_range); -EXPORT_SYMBOL(dmu_free_object); +EXPORT_SYMBOL(dmu_free_long_object); EXPORT_SYMBOL(dmu_read); EXPORT_SYMBOL(dmu_write); EXPORT_SYMBOL(dmu_prealloc); |