Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs updates from Chris Mason:
 "The largest set of changes here come from Miao Xie.  He's cleaning up
  and improving read recovery/repair for raid, and has a number of
  related fixes.

  I've merged another set of fsync fixes from Filipe, and he's also
  improved the way we handle metadata write errors to make sure we force
  the FS readonly if things go wrong.

  Otherwise we have a collection of fixes and cleanups.  Dave Sterba
  gets a cookie for removing the most lines (thanks Dave)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (139 commits)
  btrfs: Fix compile error when CONFIG_SECURITY is not set.
  Btrfs: fix compiles when CONFIG_BTRFS_FS_RUN_SANITY_TESTS is off
  btrfs: Make btrfs handle security mount options internally to avoid losing security label.
  Btrfs: send, don't delay dir move if there's a new parent inode
  btrfs: add more superblock checks
  Btrfs: fix race in WAIT_SYNC ioctl
  Btrfs: be aware of btree inode write errors to avoid fs corruption
  Btrfs: remove redundant btrfs_verify_qgroup_counts declaration.
  btrfs: fix shadow warning on cmp
  Btrfs: fix compilation errors under DEBUG
  Btrfs: fix crash of btrfs_release_extent_buffer_page
  Btrfs: add missing end_page_writeback on submit_extent_page failure
  btrfs: Fix the wrong condition judgment about subset extent map
  Btrfs: fix build_backref_tree issue with multiple shared blocks
  Btrfs: cleanup error handling in build_backref_tree
  btrfs: move checks for DUMMY_ROOT into a helper
  btrfs: new define for the inline extent data start
  btrfs: kill extent_buffer_page helper
  btrfs: drop constant param from btrfs_release_extent_buffer_page
  btrfs: hide typecast to definition of BTRFS_SEND_TRANS_STUB
  ...

1 files changed, 147 insertions, 10 deletions

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 2b0a627..3384819 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -279,8 +279,7 @@ static int io_ctl_init(struct io_ctl *io_ctl, struct inode *inode,
 	int num_pages;
 	int check_crcs = 0;
 
-	num_pages = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
-		    PAGE_CACHE_SHIFT;
+	num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE);
 
 	if (btrfs_ino(inode) != BTRFS_FREE_INO_OBJECTID)
 		check_crcs = 1;
@@ -1998,6 +1997,128 @@ static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl,
 	return merged;
 }
 
+static bool steal_from_bitmap_to_end(struct btrfs_free_space_ctl *ctl,
+				     struct btrfs_free_space *info,
+				     bool update_stat)
+{
+	struct btrfs_free_space *bitmap;
+	unsigned long i;
+	unsigned long j;
+	const u64 end = info->offset + info->bytes;
+	const u64 bitmap_offset = offset_to_bitmap(ctl, end);
+	u64 bytes;
+
+	bitmap = tree_search_offset(ctl, bitmap_offset, 1, 0);
+	if (!bitmap)
+		return false;
+
+	i = offset_to_bit(bitmap->offset, ctl->unit, end);
+	j = find_next_zero_bit(bitmap->bitmap, BITS_PER_BITMAP, i);
+	if (j == i)
+		return false;
+	bytes = (j - i) * ctl->unit;
+	info->bytes += bytes;
+
+	if (update_stat)
+		bitmap_clear_bits(ctl, bitmap, end, bytes);
+	else
+		__bitmap_clear_bits(ctl, bitmap, end, bytes);
+
+	if (!bitmap->bytes)
+		free_bitmap(ctl, bitmap);
+
+	return true;
+}
+
+static bool steal_from_bitmap_to_front(struct btrfs_free_space_ctl *ctl,
+				       struct btrfs_free_space *info,
+				       bool update_stat)
+{
+	struct btrfs_free_space *bitmap;
+	u64 bitmap_offset;
+	unsigned long i;
+	unsigned long j;
+	unsigned long prev_j;
+	u64 bytes;
+
+	bitmap_offset = offset_to_bitmap(ctl, info->offset);
+	/* If we're on a boundary, try the previous logical bitmap. */
+	if (bitmap_offset == info->offset) {
+		if (info->offset == 0)
+			return false;
+		bitmap_offset = offset_to_bitmap(ctl, info->offset - 1);
+	}
+
+	bitmap = tree_search_offset(ctl, bitmap_offset, 1, 0);
+	if (!bitmap)
+		return false;
+
+	i = offset_to_bit(bitmap->offset, ctl->unit, info->offset) - 1;
+	j = 0;
+	prev_j = (unsigned long)-1;
+	for_each_clear_bit_from(j, bitmap->bitmap, BITS_PER_BITMAP) {
+		if (j > i)
+			break;
+		prev_j = j;
+	}
+	if (prev_j == i)
+		return false;
+
+	if (prev_j == (unsigned long)-1)
+		bytes = (i + 1) * ctl->unit;
+	else
+		bytes = (i - prev_j) * ctl->unit;
+
+	info->offset -= bytes;
+	info->bytes += bytes;
+
+	if (update_stat)
+		bitmap_clear_bits(ctl, bitmap, info->offset, bytes);
+	else
+		__bitmap_clear_bits(ctl, bitmap, info->offset, bytes);
+
+	if (!bitmap->bytes)
+		free_bitmap(ctl, bitmap);
+
+	return true;
+}
+
+/*
+ * We prefer always to allocate from extent entries, both for clustered and
+ * non-clustered allocation requests. So when attempting to add a new extent
+ * entry, try to see if there's adjacent free space in bitmap entries, and if
+ * there is, migrate that space from the bitmaps to the extent.
+ * Like this we get better chances of satisfying space allocation requests
+ * because we attempt to satisfy them based on a single cache entry, and never
+ * on 2 or more entries - even if the entries represent a contiguous free space
+ * region (e.g. 1 extent entry + 1 bitmap entry starting where the extent entry
+ * ends).
+ */
+static void steal_from_bitmap(struct btrfs_free_space_ctl *ctl,
+			      struct btrfs_free_space *info,
+			      bool update_stat)
+{
+	/*
+	 * Only work with disconnected entries, as we can change their offset,
+	 * and must be extent entries.
+	 */
+	ASSERT(!info->bitmap);
+	ASSERT(RB_EMPTY_NODE(&info->offset_index));
+
+	if (ctl->total_bitmaps > 0) {
+		bool stole_end;
+		bool stole_front = false;
+
+		stole_end = steal_from_bitmap_to_end(ctl, info, update_stat);
+		if (ctl->total_bitmaps > 0)
+			stole_front = steal_from_bitmap_to_front(ctl, info,
+								 update_stat);
+
+		if (stole_end || stole_front)
+			try_merge_free_space(ctl, info, update_stat);
+	}
+}
+
 int __btrfs_add_free_space(struct btrfs_free_space_ctl *ctl,
 			   u64 offset, u64 bytes)
 {
@@ -2010,6 +2131,7 @@ int __btrfs_add_free_space(struct btrfs_free_space_ctl *ctl,
 
 	info->offset = offset;
 	info->bytes = bytes;
+	RB_CLEAR_NODE(&info->offset_index);
 
 	spin_lock(&ctl->tree_lock);
 
@@ -2029,6 +2151,14 @@ int __btrfs_add_free_space(struct btrfs_free_space_ctl *ctl,
 		goto out;
 	}
 link:
+	/*
+	 * Only steal free space from adjacent bitmaps if we're sure we're not
+	 * going to add the new free space to existing bitmap entries - because
+	 * that would mean unnecessary work that would be reverted. Therefore
+	 * attempt to steal space from bitmaps if we're adding an extent entry.
+	 */
+	steal_from_bitmap(ctl, info, true);
+
 	ret = link_free_space(ctl, info);
 	if (ret)
 		kmem_cache_free(btrfs_free_space_cachep, info);
@@ -2205,10 +2335,13 @@ __btrfs_return_cluster_to_free_space(
 		entry = rb_entry(node, struct btrfs_free_space, offset_index);
 		node = rb_next(&entry->offset_index);
 		rb_erase(&entry->offset_index, &cluster->root);
+		RB_CLEAR_NODE(&entry->offset_index);
 
 		bitmap = (entry->bitmap != NULL);
-		if (!bitmap)
+		if (!bitmap) {
 			try_merge_free_space(ctl, entry, false);
+			steal_from_bitmap(ctl, entry, false);
+		}
 		tree_insert_offset(&ctl->free_space_offset,
 				   entry->offset, &entry->offset_index, bitmap);
 	}
@@ -3033,10 +3166,10 @@ struct inode *lookup_free_ino_inode(struct btrfs_root *root,
 {
 	struct inode *inode = NULL;
 
-	spin_lock(&root->cache_lock);
-	if (root->cache_inode)
-		inode = igrab(root->cache_inode);
-	spin_unlock(&root->cache_lock);
+	spin_lock(&root->ino_cache_lock);
+	if (root->ino_cache_inode)
+		inode = igrab(root->ino_cache_inode);
+	spin_unlock(&root->ino_cache_lock);
 	if (inode)
 		return inode;
 
@@ -3044,10 +3177,10 @@ struct inode *lookup_free_ino_inode(struct btrfs_root *root,
 	if (IS_ERR(inode))
 		return inode;
 
-	spin_lock(&root->cache_lock);
+	spin_lock(&root->ino_cache_lock);
 	if (!btrfs_fs_closing(root->fs_info))
-		root->cache_inode = igrab(inode);
-	spin_unlock(&root->cache_lock);
+		root->ino_cache_inode = igrab(inode);
+	spin_unlock(&root->ino_cache_lock);
 
 	return inode;
 }
@@ -3176,6 +3309,7 @@ again:
 		map = NULL;
 		add_new_bitmap(ctl, info, offset);
 		bitmap_info = info;
+		info = NULL;
 	}
 
 	bytes_added = add_bytes_to_bitmap(ctl, bitmap_info, offset, bytes);
@@ -3186,6 +3320,8 @@ again:
 	if (bytes)
 		goto again;
 
+	if (info)
+		kmem_cache_free(btrfs_free_space_cachep, info);
 	if (map)
 		kfree(map);
 	return 0;
@@ -3260,6 +3396,7 @@ have_info:
 			goto have_info;
 		}
 
+		ret = 0;
 		goto out;
 	}