aboutsummaryrefslogtreecommitdiffstats
path: root/fs/btrfs/delayed-ref.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs/delayed-ref.c')
-rw-r--r--fs/btrfs/delayed-ref.c101
1 files changed, 0 insertions, 101 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 902ce507c4e3..e807b143b857 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -319,107 +319,6 @@ out:
319} 319}
320 320
321/* 321/*
322 * helper function to lookup reference count and flags of extent.
323 *
324 * the head node for delayed ref is used to store the sum of all the
325 * reference count modifications queued up in the rbtree. the head
326 * node may also store the extent flags to set. This way you can check
327 * to see what the reference count and extent flags would be if all of
328 * the delayed refs are not processed.
329 */
330int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
331 struct btrfs_root *root, u64 bytenr,
332 u64 num_bytes, u64 *refs, u64 *flags)
333{
334 struct btrfs_delayed_ref_node *ref;
335 struct btrfs_delayed_ref_head *head;
336 struct btrfs_delayed_ref_root *delayed_refs;
337 struct btrfs_path *path;
338 struct btrfs_extent_item *ei;
339 struct extent_buffer *leaf;
340 struct btrfs_key key;
341 u32 item_size;
342 u64 num_refs;
343 u64 extent_flags;
344 int ret;
345
346 path = btrfs_alloc_path();
347 if (!path)
348 return -ENOMEM;
349
350 key.objectid = bytenr;
351 key.type = BTRFS_EXTENT_ITEM_KEY;
352 key.offset = num_bytes;
353 delayed_refs = &trans->transaction->delayed_refs;
354again:
355 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
356 &key, path, 0, 0);
357 if (ret < 0)
358 goto out;
359
360 if (ret == 0) {
361 leaf = path->nodes[0];
362 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
363 if (item_size >= sizeof(*ei)) {
364 ei = btrfs_item_ptr(leaf, path->slots[0],
365 struct btrfs_extent_item);
366 num_refs = btrfs_extent_refs(leaf, ei);
367 extent_flags = btrfs_extent_flags(leaf, ei);
368 } else {
369#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
370 struct btrfs_extent_item_v0 *ei0;
371 BUG_ON(item_size != sizeof(*ei0));
372 ei0 = btrfs_item_ptr(leaf, path->slots[0],
373 struct btrfs_extent_item_v0);
374 num_refs = btrfs_extent_refs_v0(leaf, ei0);
375 /* FIXME: this isn't correct for data */
376 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
377#else
378 BUG();
379#endif
380 }
381 BUG_ON(num_refs == 0);
382 } else {
383 num_refs = 0;
384 extent_flags = 0;
385 ret = 0;
386 }
387
388 spin_lock(&delayed_refs->lock);
389 ref = find_ref_head(&delayed_refs->root, bytenr, NULL);
390 if (ref) {
391 head = btrfs_delayed_node_to_head(ref);
392 if (!mutex_trylock(&head->mutex)) {
393 atomic_inc(&ref->refs);
394 spin_unlock(&delayed_refs->lock);
395
396 btrfs_release_path(root->fs_info->extent_root, path);
397
398 mutex_lock(&head->mutex);
399 mutex_unlock(&head->mutex);
400 btrfs_put_delayed_ref(ref);
401 goto again;
402 }
403 if (head->extent_op && head->extent_op->update_flags)
404 extent_flags |= head->extent_op->flags_to_set;
405 else
406 BUG_ON(num_refs == 0);
407
408 num_refs += ref->ref_mod;
409 mutex_unlock(&head->mutex);
410 }
411 WARN_ON(num_refs == 0);
412 if (refs)
413 *refs = num_refs;
414 if (flags)
415 *flags = extent_flags;
416out:
417 spin_unlock(&delayed_refs->lock);
418 btrfs_free_path(path);
419 return ret;
420}
421
422/*
423 * helper function to update an extent delayed ref in the 322 * helper function to update an extent delayed ref in the
424 * rbtree. existing and update must both have the same 323 * rbtree. existing and update must both have the same
425 * bytenr and parent 324 * bytenr and parent