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path: root/fs/btrfs/extent_map.c
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Diffstat (limited to 'fs/btrfs/extent_map.c')
-rw-r--r--fs/btrfs/extent_map.c64
1 files changed, 61 insertions, 3 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 7c97b330145..fdb7a8db3b5 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -11,7 +11,7 @@ static struct kmem_cache *extent_map_cache;
int __init extent_map_init(void)
{
- extent_map_cache = kmem_cache_create("extent_map",
+ extent_map_cache = kmem_cache_create("btrfs_extent_map",
sizeof(struct extent_map), 0,
SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
if (!extent_map_cache)
@@ -35,6 +35,7 @@ void extent_map_exit(void)
void extent_map_tree_init(struct extent_map_tree *tree)
{
tree->map = RB_ROOT;
+ INIT_LIST_HEAD(&tree->modified_extents);
rwlock_init(&tree->lock);
}
@@ -48,13 +49,15 @@ void extent_map_tree_init(struct extent_map_tree *tree)
struct extent_map *alloc_extent_map(void)
{
struct extent_map *em;
- em = kmem_cache_alloc(extent_map_cache, GFP_NOFS);
+ em = kmem_cache_zalloc(extent_map_cache, GFP_NOFS);
if (!em)
return NULL;
em->in_tree = 0;
em->flags = 0;
em->compress_type = BTRFS_COMPRESS_NONE;
+ em->generation = 0;
atomic_set(&em->refs, 1);
+ INIT_LIST_HEAD(&em->list);
return em;
}
@@ -72,6 +75,7 @@ void free_extent_map(struct extent_map *em)
WARN_ON(atomic_read(&em->refs) == 0);
if (atomic_dec_and_test(&em->refs)) {
WARN_ON(em->in_tree);
+ WARN_ON(!list_empty(&em->list));
kmem_cache_free(extent_map_cache, em);
}
}
@@ -167,6 +171,10 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next)
if (test_bit(EXTENT_FLAG_COMPRESSED, &prev->flags))
return 0;
+ if (test_bit(EXTENT_FLAG_LOGGING, &prev->flags) ||
+ test_bit(EXTENT_FLAG_LOGGING, &next->flags))
+ return 0;
+
if (extent_map_end(prev) == next->start &&
prev->flags == next->flags &&
prev->bdev == next->bdev &&
@@ -194,10 +202,17 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
merge = rb_entry(rb, struct extent_map, rb_node);
if (rb && mergable_maps(merge, em)) {
em->start = merge->start;
+ em->orig_start = merge->orig_start;
em->len += merge->len;
em->block_len += merge->block_len;
em->block_start = merge->block_start;
merge->in_tree = 0;
+ em->mod_len = (em->mod_len + em->mod_start) - merge->mod_start;
+ em->mod_start = merge->mod_start;
+ em->generation = max(em->generation, merge->generation);
+ list_move(&em->list, &tree->modified_extents);
+
+ list_del_init(&merge->list);
rb_erase(&merge->rb_node, &tree->map);
free_extent_map(merge);
}
@@ -211,14 +226,30 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
em->block_len += merge->len;
rb_erase(&merge->rb_node, &tree->map);
merge->in_tree = 0;
+ em->mod_len = (merge->mod_start + merge->mod_len) - em->mod_start;
+ em->generation = max(em->generation, merge->generation);
+ list_del_init(&merge->list);
free_extent_map(merge);
}
}
-int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len)
+/**
+ * unpin_extent_cache - unpin an extent from the cache
+ * @tree: tree to unpin the extent in
+ * @start: logical offset in the file
+ * @len: length of the extent
+ * @gen: generation that this extent has been modified in
+ *
+ * Called after an extent has been written to disk properly. Set the generation
+ * to the generation that actually added the file item to the inode so we know
+ * we need to sync this extent when we call fsync().
+ */
+int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
+ u64 gen)
{
int ret = 0;
struct extent_map *em;
+ bool prealloc = false;
write_lock(&tree->lock);
em = lookup_extent_mapping(tree, start, len);
@@ -228,10 +259,25 @@ int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len)
if (!em)
goto out;
+ if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+ list_move(&em->list, &tree->modified_extents);
+ em->generation = gen;
clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+ em->mod_start = em->start;
+ em->mod_len = em->len;
+
+ if (test_bit(EXTENT_FLAG_FILLING, &em->flags)) {
+ prealloc = true;
+ clear_bit(EXTENT_FLAG_FILLING, &em->flags);
+ }
try_merge_map(tree, em);
+ if (prealloc) {
+ em->mod_start = em->start;
+ em->mod_len = em->len;
+ }
+
free_extent_map(em);
out:
write_unlock(&tree->lock);
@@ -239,6 +285,13 @@ out:
}
+void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)
+{
+ clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
+ if (em->in_tree)
+ try_merge_map(tree, em);
+}
+
/**
* add_extent_mapping - add new extent map to the extent tree
* @tree: tree to insert new map in
@@ -269,6 +322,9 @@ int add_extent_mapping(struct extent_map_tree *tree,
}
atomic_inc(&em->refs);
+ em->mod_start = em->start;
+ em->mod_len = em->len;
+
try_merge_map(tree, em);
out:
return ret;
@@ -358,6 +414,8 @@ int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
rb_erase(&em->rb_node, &tree->map);
+ if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+ list_del_init(&em->list);
em->in_tree = 0;
return ret;
}