These helpers are extent map specific, move them to extent_map.c.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
int delay_iput);
void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work);
-int btrfs_add_extent_mapping(struct extent_map_tree *em_tree,
- struct extent_map **em_in, u64 start, u64 len);
struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode,
struct page *page, size_t pg_offset, u64 start,
u64 len, int create);
setup_extent_mapping(tree, new, modified);
}
+
+static struct extent_map *next_extent_map(struct extent_map *em)
+{
+ struct rb_node *next;
+
+ next = rb_next(&em->rb_node);
+ if (!next)
+ return NULL;
+ return container_of(next, struct extent_map, rb_node);
+}
+
+static struct extent_map *prev_extent_map(struct extent_map *em)
+{
+ struct rb_node *prev;
+
+ prev = rb_prev(&em->rb_node);
+ if (!prev)
+ return NULL;
+ return container_of(prev, struct extent_map, rb_node);
+}
+
+/* helper for btfs_get_extent. Given an existing extent in the tree,
+ * the existing extent is the nearest extent to map_start,
+ * and an extent that you want to insert, deal with overlap and insert
+ * the best fitted new extent into the tree.
+ */
+static int merge_extent_mapping(struct extent_map_tree *em_tree,
+ struct extent_map *existing,
+ struct extent_map *em,
+ u64 map_start)
+{
+ struct extent_map *prev;
+ struct extent_map *next;
+ u64 start;
+ u64 end;
+ u64 start_diff;
+
+ BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
+
+ if (existing->start > map_start) {
+ next = existing;
+ prev = prev_extent_map(next);
+ } else {
+ prev = existing;
+ next = next_extent_map(prev);
+ }
+
+ start = prev ? extent_map_end(prev) : em->start;
+ start = max_t(u64, start, em->start);
+ end = next ? next->start : extent_map_end(em);
+ end = min_t(u64, end, extent_map_end(em));
+ start_diff = start - em->start;
+ em->start = start;
+ em->len = end - start;
+ if (em->block_start < EXTENT_MAP_LAST_BYTE &&
+ !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
+ em->block_start += start_diff;
+ em->block_len = em->len;
+ }
+ return add_extent_mapping(em_tree, em, 0);
+}
+
+/**
+ * btrfs_add_extent_mapping - add extent mapping into em_tree
+ * @em_tree - the extent tree into which we want to insert the extent mapping
+ * @em_in - extent we are inserting
+ * @start - start of the logical range btrfs_get_extent() is requesting
+ * @len - length of the logical range btrfs_get_extent() is requesting
+ *
+ * Note that @em_in's range may be different from [start, start+len),
+ * but they must be overlapped.
+ *
+ * Insert @em_in into @em_tree. In case there is an overlapping range, handle
+ * the -EEXIST by either:
+ * a) Returning the existing extent in @em_in if @start is within the
+ * existing em.
+ * b) Merge the existing extent with @em_in passed in.
+ *
+ * Return 0 on success, otherwise -EEXIST.
+ *
+ */
+int btrfs_add_extent_mapping(struct extent_map_tree *em_tree,
+ struct extent_map **em_in, u64 start, u64 len)
+{
+ int ret;
+ struct extent_map *em = *em_in;
+
+ ret = add_extent_mapping(em_tree, em, 0);
+ /* it is possible that someone inserted the extent into the tree
+ * while we had the lock dropped. It is also possible that
+ * an overlapping map exists in the tree
+ */
+ if (ret == -EEXIST) {
+ struct extent_map *existing;
+
+ ret = 0;
+
+ existing = search_extent_mapping(em_tree, start, len);
+ /*
+ * existing will always be non-NULL, since there must be
+ * extent causing the -EEXIST.
+ */
+ if (start >= existing->start &&
+ start < extent_map_end(existing)) {
+ free_extent_map(em);
+ *em_in = existing;
+ ret = 0;
+ } else {
+ /*
+ * The existing extent map is the one nearest to
+ * the [start, start + len) range which overlaps
+ */
+ ret = merge_extent_mapping(em_tree, existing,
+ em, start);
+ free_extent_map(existing);
+ if (ret) {
+ free_extent_map(em);
+ *em_in = NULL;
+ }
+ }
+ }
+
+ ASSERT(ret == 0 || ret == -EEXIST);
+ return ret;
+}
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
+int btrfs_add_extent_mapping(struct extent_map_tree *em_tree,
+ struct extent_map **em_in, u64 start, u64 len);
#endif
goto out_fail;
}
-/* Find next extent map of a given extent map, caller needs to ensure locks */
-static struct extent_map *next_extent_map(struct extent_map *em)
-{
- struct rb_node *next;
-
- next = rb_next(&em->rb_node);
- if (!next)
- return NULL;
- return container_of(next, struct extent_map, rb_node);
-}
-
-static struct extent_map *prev_extent_map(struct extent_map *em)
-{
- struct rb_node *prev;
-
- prev = rb_prev(&em->rb_node);
- if (!prev)
- return NULL;
- return container_of(prev, struct extent_map, rb_node);
-}
-
-/* helper for btfs_get_extent. Given an existing extent in the tree,
- * the existing extent is the nearest extent to map_start,
- * and an extent that you want to insert, deal with overlap and insert
- * the best fitted new extent into the tree.
- */
-static int merge_extent_mapping(struct extent_map_tree *em_tree,
- struct extent_map *existing,
- struct extent_map *em,
- u64 map_start)
-{
- struct extent_map *prev;
- struct extent_map *next;
- u64 start;
- u64 end;
- u64 start_diff;
-
- BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
-
- if (existing->start > map_start) {
- next = existing;
- prev = prev_extent_map(next);
- } else {
- prev = existing;
- next = next_extent_map(prev);
- }
-
- start = prev ? extent_map_end(prev) : em->start;
- start = max_t(u64, start, em->start);
- end = next ? next->start : extent_map_end(em);
- end = min_t(u64, end, extent_map_end(em));
- start_diff = start - em->start;
- em->start = start;
- em->len = end - start;
- if (em->block_start < EXTENT_MAP_LAST_BYTE &&
- !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
- em->block_start += start_diff;
- em->block_len = em->len;
- }
- return add_extent_mapping(em_tree, em, 0);
-}
-
static noinline int uncompress_inline(struct btrfs_path *path,
struct page *page,
size_t pg_offset, u64 extent_offset,
return ret;
}
-int btrfs_add_extent_mapping(struct extent_map_tree *em_tree,
- struct extent_map **em_in, u64 start, u64 len)
-{
- int ret;
- struct extent_map *em = *em_in;
-
- ret = add_extent_mapping(em_tree, em, 0);
- /* it is possible that someone inserted the extent into the tree
- * while we had the lock dropped. It is also possible that
- * an overlapping map exists in the tree
- */
- if (ret == -EEXIST) {
- struct extent_map *existing;
-
- ret = 0;
-
- existing = search_extent_mapping(em_tree, start, len);
- /*
- * existing will always be non-NULL, since there must be
- * extent causing the -EEXIST.
- */
- if (start >= existing->start &&
- start < extent_map_end(existing)) {
- free_extent_map(em);
- *em_in = existing;
- ret = 0;
- } else {
- /*
- * The existing extent map is the one nearest to
- * the [start, start + len) range which overlaps
- */
- ret = merge_extent_mapping(em_tree, existing,
- em, start);
- free_extent_map(existing);
- if (ret) {
- free_extent_map(em);
- *em_in = NULL;
- }
- }
- }
-
- ASSERT(ret == 0 || ret == -EEXIST);
- return ret;
-}
-
/*
* a bit scary, this does extent mapping from logical file offset to the disk.
* the ugly parts come from merging extents from the disk with the in-ram
projects / openwrt / staging / blogic.git / commitdiff