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-rw-r--r--fs/ext4/ext4.h1
-rw-r--r--fs/ext4/extents.c79
-rw-r--r--fs/ext4/extents_status.c53
-rw-r--r--fs/ext4/extents_status.h12
-rw-r--r--fs/ext4/inode.c79
5 files changed, 206 insertions, 18 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index fc0f41dbf90b..d85fd5c8a2c4 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3155,6 +3155,7 @@ extern int ext4_swap_extents(handle_t *handle, struct inode *inode1,
struct inode *inode2, ext4_lblk_t lblk1,
ext4_lblk_t lblk2, ext4_lblk_t count,
int mark_unwritten,int *err);
+extern int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu);
/* move_extent.c */
extern void ext4_double_down_write_data_sem(struct inode *first,
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 95796f00e4e6..26481e543312 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -5930,3 +5930,82 @@ ext4_swap_extents(handle_t *handle, struct inode *inode1,
}
return replaced_count;
}
+
+/*
+ * ext4_clu_mapped - determine whether any block in a logical cluster has
+ * been mapped to a physical cluster
+ *
+ * @inode - file containing the logical cluster
+ * @lclu - logical cluster of interest
+ *
+ * Returns 1 if any block in the logical cluster is mapped, signifying
+ * that a physical cluster has been allocated for it. Otherwise,
+ * returns 0. Can also return negative error codes. Derived from
+ * ext4_ext_map_blocks().
+ */
+int ext4_clu_mapped(struct inode *inode, ext4_lblk_t lclu)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ struct ext4_ext_path *path;
+ int depth, mapped = 0, err = 0;
+ struct ext4_extent *extent;
+ ext4_lblk_t first_lblk, first_lclu, last_lclu;
+
+ /* search for the extent closest to the first block in the cluster */
+ path = ext4_find_extent(inode, EXT4_C2B(sbi, lclu), NULL, 0);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ path = NULL;
+ goto out;
+ }
+
+ depth = ext_depth(inode);
+
+ /*
+ * A consistent leaf must not be empty. This situation is possible,
+ * though, _during_ tree modification, and it's why an assert can't
+ * be put in ext4_find_extent().
+ */
+ if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
+ EXT4_ERROR_INODE(inode,
+ "bad extent address - lblock: %lu, depth: %d, pblock: %lld",
+ (unsigned long) EXT4_C2B(sbi, lclu),
+ depth, path[depth].p_block);
+ err = -EFSCORRUPTED;
+ goto out;
+ }
+
+ extent = path[depth].p_ext;
+
+ /* can't be mapped if the extent tree is empty */
+ if (extent == NULL)
+ goto out;
+
+ first_lblk = le32_to_cpu(extent->ee_block);
+ first_lclu = EXT4_B2C(sbi, first_lblk);
+
+ /*
+ * Three possible outcomes at this point - found extent spanning
+ * the target cluster, to the left of the target cluster, or to the
+ * right of the target cluster. The first two cases are handled here.
+ * The last case indicates the target cluster is not mapped.
+ */
+ if (lclu >= first_lclu) {
+ last_lclu = EXT4_B2C(sbi, first_lblk +
+ ext4_ext_get_actual_len(extent) - 1);
+ if (lclu <= last_lclu) {
+ mapped = 1;
+ } else {
+ first_lblk = ext4_ext_next_allocated_block(path);
+ first_lclu = EXT4_B2C(sbi, first_lblk);
+ if (lclu == first_lclu)
+ mapped = 1;
+ }
+ }
+
+out:
+ ext4_ext_drop_refs(path);
+ kfree(path);
+
+ return err ? err : mapped;
+}
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 194785ce890a..c5d456e12062 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -1552,3 +1552,56 @@ bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk)
return ret;
}
+
+/*
+ * ext4_es_insert_delayed_block - adds a delayed block to the extents status
+ * tree, adding a pending reservation where
+ * needed
+ *
+ * @inode - file containing the newly added block
+ * @lblk - logical block to be added
+ * @allocated - indicates whether a physical cluster has been allocated for
+ * the logical cluster that contains the block
+ *
+ * Returns 0 on success, negative error code on failure.
+ */
+int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk,
+ bool allocated)
+{
+ struct extent_status newes;
+ int err = 0;
+
+ es_debug("add [%u/1) delayed to extent status tree of inode %lu\n",
+ lblk, inode->i_ino);
+
+ newes.es_lblk = lblk;
+ newes.es_len = 1;
+ ext4_es_store_pblock_status(&newes, ~0, EXTENT_STATUS_DELAYED);
+ trace_ext4_es_insert_delayed_block(inode, &newes, allocated);
+
+ ext4_es_insert_extent_check(inode, &newes);
+
+ write_lock(&EXT4_I(inode)->i_es_lock);
+
+ err = __es_remove_extent(inode, lblk, lblk);
+ if (err != 0)
+ goto error;
+retry:
+ err = __es_insert_extent(inode, &newes);
+ if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb),
+ 128, EXT4_I(inode)))
+ goto retry;
+ if (err != 0)
+ goto error;
+
+ if (allocated)
+ __insert_pending(inode, lblk);
+
+error:
+ write_unlock(&EXT4_I(inode)->i_es_lock);
+
+ ext4_es_print_tree(inode);
+ ext4_print_pending_tree(inode);
+
+ return err;
+}
diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 379b7171c67c..9d3c676ec623 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -178,6 +178,16 @@ static inline int ext4_es_is_hole(struct extent_status *es)
return (ext4_es_type(es) & EXTENT_STATUS_HOLE) != 0;
}
+static inline int ext4_es_is_mapped(struct extent_status *es)
+{
+ return (ext4_es_is_written(es) || ext4_es_is_unwritten(es));
+}
+
+static inline int ext4_es_is_delonly(struct extent_status *es)
+{
+ return (ext4_es_is_delayed(es) && !ext4_es_is_unwritten(es));
+}
+
static inline void ext4_es_set_referenced(struct extent_status *es)
{
es->es_pblk |= ((ext4_fsblk_t)EXTENT_STATUS_REFERENCED) << ES_SHIFT;
@@ -232,5 +242,7 @@ extern void ext4_exit_pending(void);
extern void ext4_init_pending_tree(struct ext4_pending_tree *tree);
extern void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk);
extern bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk);
+extern int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk,
+ bool allocated);
#endif /* _EXT4_EXTENTS_STATUS_H */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index b83bf3308b5e..57c6dd38f071 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1781,6 +1781,65 @@ static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
}
/*
+ * ext4_insert_delayed_block - adds a delayed block to the extents status
+ * tree, incrementing the reserved cluster/block
+ * count or making a pending reservation
+ * where needed
+ *
+ * @inode - file containing the newly added block
+ * @lblk - logical block to be added
+ *
+ * Returns 0 on success, negative error code on failure.
+ */
+static int ext4_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int ret;
+ bool allocated = false;
+
+ /*
+ * If the cluster containing lblk is shared with a delayed,
+ * written, or unwritten extent in a bigalloc file system, it's
+ * already been accounted for and does not need to be reserved.
+ * A pending reservation must be made for the cluster if it's
+ * shared with a written or unwritten extent and doesn't already
+ * have one. Written and unwritten extents can be purged from the
+ * extents status tree if the system is under memory pressure, so
+ * it's necessary to examine the extent tree if a search of the
+ * extents status tree doesn't get a match.
+ */
+ if (sbi->s_cluster_ratio == 1) {
+ ret = ext4_da_reserve_space(inode);
+ if (ret != 0) /* ENOSPC */
+ goto errout;
+ } else { /* bigalloc */
+ if (!ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk)) {
+ if (!ext4_es_scan_clu(inode,
+ &ext4_es_is_mapped, lblk)) {
+ ret = ext4_clu_mapped(inode,
+ EXT4_B2C(sbi, lblk));
+ if (ret < 0)
+ goto errout;
+ if (ret == 0) {
+ ret = ext4_da_reserve_space(inode);
+ if (ret != 0) /* ENOSPC */
+ goto errout;
+ } else {
+ allocated = true;
+ }
+ } else {
+ allocated = true;
+ }
+ }
+ }
+
+ ret = ext4_es_insert_delayed_block(inode, lblk, allocated);
+
+errout:
+ return ret;
+}
+
+/*
* This function is grabs code from the very beginning of
* ext4_map_blocks, but assumes that the caller is from delayed write
* time. This function looks up the requested blocks and sets the
@@ -1864,25 +1923,9 @@ add_delayed:
* XXX: __block_prepare_write() unmaps passed block,
* is it OK?
*/
- /*
- * If the block was allocated from previously allocated cluster,
- * then we don't need to reserve it again. However we still need
- * to reserve metadata for every block we're going to write.
- */
- if (EXT4_SB(inode->i_sb)->s_cluster_ratio == 1 ||
- !ext4_es_scan_clu(inode,
- &ext4_es_is_delayed, map->m_lblk)) {
- ret = ext4_da_reserve_space(inode);
- if (ret) {
- /* not enough space to reserve */
- retval = ret;
- goto out_unlock;
- }
- }
- ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
- ~0, EXTENT_STATUS_DELAYED);
- if (ret) {
+ ret = ext4_insert_delayed_block(inode, map->m_lblk);
+ if (ret != 0) {
retval = ret;
goto out_unlock;
}