diff options
Diffstat (limited to 'fs/ext4/extents_status.c')
| -rw-r--r-- | fs/ext4/extents_status.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c index c5d456e12062..c92fbf444d08 100644 --- a/fs/ext4/extents_status.c +++ b/fs/ext4/extents_status.c @@ -150,6 +150,8 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan); static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan, struct ext4_inode_info *locked_ei); +static void __revise_pending(struct inode *inode, ext4_lblk_t lblk, + ext4_lblk_t len); int __init ext4_init_es(void) { @@ -808,6 +810,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk, struct extent_status newes; ext4_lblk_t end = lblk + len - 1; int err = 0; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); es_debug("add [%u/%u) %llu %x to extent status tree of inode %lu\n", lblk, len, pblk, status, inode->i_ino); @@ -844,6 +847,11 @@ retry: if (err == -ENOMEM && !ext4_es_is_delayed(&newes)) err = 0; + if (sbi->s_cluster_ratio > 1 && test_opt(inode->i_sb, DELALLOC) && + (status & EXTENT_STATUS_WRITTEN || + status & EXTENT_STATUS_UNWRITTEN)) + __revise_pending(inode, lblk, len); + error: write_unlock(&EXT4_I(inode)->i_es_lock); @@ -1605,3 +1613,170 @@ error: return err; } + +/* + * __es_delayed_clu - count number of clusters containing blocks that + * are delayed only + * + * @inode - file containing block range + * @start - logical block defining start of range + * @end - logical block defining end of range + * + * Returns the number of clusters containing only delayed (not delayed + * and unwritten) blocks in the range specified by @start and @end. Any + * cluster or part of a cluster within the range and containing a delayed + * and not unwritten block within the range is counted as a whole cluster. + */ +static unsigned int __es_delayed_clu(struct inode *inode, ext4_lblk_t start, + ext4_lblk_t end) +{ + struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; + struct extent_status *es; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + struct rb_node *node; + ext4_lblk_t first_lclu, last_lclu; + unsigned long long last_counted_lclu; + unsigned int n = 0; + + /* guaranteed to be unequal to any ext4_lblk_t value */ + last_counted_lclu = ~0ULL; + + es = __es_tree_search(&tree->root, start); + + while (es && (es->es_lblk <= end)) { + if (ext4_es_is_delonly(es)) { + if (es->es_lblk <= start) + first_lclu = EXT4_B2C(sbi, start); + else + first_lclu = EXT4_B2C(sbi, es->es_lblk); + + if (ext4_es_end(es) >= end) + last_lclu = EXT4_B2C(sbi, end); + else + last_lclu = EXT4_B2C(sbi, ext4_es_end(es)); + + if (first_lclu == last_counted_lclu) + n += last_lclu - first_lclu; + else + n += last_lclu - first_lclu + 1; + last_counted_lclu = last_lclu; + } + node = rb_next(&es->rb_node); + if (!node) + break; + es = rb_entry(node, struct extent_status, rb_node); + } + + return n; +} + +/* + * ext4_es_delayed_clu - count number of clusters containing blocks that + * are both delayed and unwritten + * + * @inode - file containing block range + * @lblk - logical block defining start of range + * @len - number of blocks in range + * + * Locking for external use of __es_delayed_clu(). + */ +unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk, + ext4_lblk_t len) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + ext4_lblk_t end; + unsigned int n; + + if (len == 0) + return 0; + + end = lblk + len - 1; + WARN_ON(end < lblk); + + read_lock(&ei->i_es_lock); + + n = __es_delayed_clu(inode, lblk, end); + + read_unlock(&ei->i_es_lock); + + return n; +} + +/* + * __revise_pending - makes, cancels, or leaves unchanged pending cluster + * reservations for a specified block range depending + * upon the presence or absence of delayed blocks + * outside the range within clusters at the ends of the + * range + * + * @inode - file containing the range + * @lblk - logical block defining the start of range + * @len - length of range in blocks + * + * Used after a newly allocated extent is added to the extents status tree. + * Requires that the extents in the range have either written or unwritten + * status. Must be called while holding i_es_lock. + */ +static void __revise_pending(struct inode *inode, ext4_lblk_t lblk, + ext4_lblk_t len) +{ + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + ext4_lblk_t end = lblk + len - 1; + ext4_lblk_t first, last; + bool f_del = false, l_del = false; + + if (len == 0) + return; + + /* + * Two cases - block range within single cluster and block range + * spanning two or more clusters. Note that a cluster belonging + * to a range starting and/or ending on a cluster boundary is treated + * as if it does not contain a delayed extent. The new range may + * have allocated space for previously delayed blocks out to the + * cluster boundary, requiring that any pre-existing pending + * reservation be canceled. Because this code only looks at blocks + * outside the range, it should revise pending reservations + * correctly even if the extent represented by the range can't be + * inserted in the extents status tree due to ENOSPC. + */ + + if (EXT4_B2C(sbi, lblk) == EXT4_B2C(sbi, end)) { + first = EXT4_LBLK_CMASK(sbi, lblk); + if (first != lblk) + f_del = __es_scan_range(inode, &ext4_es_is_delonly, + first, lblk - 1); + if (f_del) { + __insert_pending(inode, first); + } else { + last = EXT4_LBLK_CMASK(sbi, end) + + sbi->s_cluster_ratio - 1; + if (last != end) + l_del = __es_scan_range(inode, + &ext4_es_is_delonly, + end + 1, last); + if (l_del) + __insert_pending(inode, last); + else + __remove_pending(inode, last); + } + } else { + first = EXT4_LBLK_CMASK(sbi, lblk); + if (first != lblk) + f_del = __es_scan_range(inode, &ext4_es_is_delonly, + first, lblk - 1); + if (f_del) + __insert_pending(inode, first); + else + __remove_pending(inode, first); + + last = EXT4_LBLK_CMASK(sbi, end) + sbi->s_cluster_ratio - 1; + if (last != end) + l_del = __es_scan_range(inode, &ext4_es_is_delonly, + end + 1, last); + if (l_del) + __insert_pending(inode, last); + else + __remove_pending(inode, last); + } +} |