[PATCH 19/36] btrfs: set max_extent_size properly

[Josef Bacik <josef@toxicpanda.com>]

From: Josef Bacik <jbacik@fb.com>

We can't use entry->bytes if our entry is a bitmap entry, we need to use
entry->max_extent_size in that case.  Fix up all the logic to make this
consistent.

Signed-off-by: Josef Bacik <jbacik@fb.com>
---
 fs/btrfs/free-space-cache.c | 29 +++++++++++++++++++----------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index e077ad3b4549..2e96ee7da3ec 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -1770,6 +1770,18 @@ static int search_bitmap(struct btrfs_free_space_ctl *ctl,
 	return -1;
 }
 
+static void set_max_extent_size(struct btrfs_free_space *entry,
+				u64 *max_extent_size)
+{
+	if (entry->bitmap) {
+		if (entry->max_extent_size > *max_extent_size)
+			*max_extent_size = entry->max_extent_size;
+	} else {
+		if (entry->bytes > *max_extent_size)
+			*max_extent_size = entry->bytes;
+	}
+}
+
 /* Cache the size of the max extent in bytes */
 static struct btrfs_free_space *
 find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes,
@@ -1791,8 +1803,7 @@ find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes,
 	for (node = &entry->offset_index; node; node = rb_next(node)) {
 		entry = rb_entry(node, struct btrfs_free_space, offset_index);
 		if (entry->bytes < *bytes) {
-			if (entry->bytes > *max_extent_size)
-				*max_extent_size = entry->bytes;
+			set_max_extent_size(entry, max_extent_size);
 			continue;
 		}
 
@@ -1810,8 +1821,7 @@ find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes,
 		}
 
 		if (entry->bytes < *bytes + align_off) {
-			if (entry->bytes > *max_extent_size)
-				*max_extent_size = entry->bytes;
+			set_max_extent_size(entry, max_extent_size);
 			continue;
 		}
 
@@ -1823,8 +1833,8 @@ find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes,
 				*offset = tmp;
 				*bytes = size;
 				return entry;
-			} else if (size > *max_extent_size) {
-				*max_extent_size = size;
+			} else {
+				set_max_extent_size(entry, max_extent_size);
 			}
 			continue;
 		}
@@ -2684,8 +2694,7 @@ static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
 
 	err = search_bitmap(ctl, entry, &search_start, &search_bytes, true);
 	if (err) {
-		if (search_bytes > *max_extent_size)
-			*max_extent_size = search_bytes;
+		set_max_extent_size(entry, max_extent_size);
 		return 0;
 	}
 
@@ -2722,8 +2731,8 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
 
 	entry = rb_entry(node, struct btrfs_free_space, offset_index);
 	while (1) {
-		if (entry->bytes < bytes && entry->bytes > *max_extent_size)
-			*max_extent_size = entry->bytes;
+		if (entry->bytes < bytes)
+			set_max_extent_size(entry, max_extent_size);
 
 		if (entry->bytes < bytes ||
 		    (!entry->bitmap && entry->offset < min_start)) {
-- 
2.14.3