1 files changed, 30 insertions, 27 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index cfb3cf711b34..d58bef130a41 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3925,7 +3925,6 @@ static int can_overcommit(struct btrfs_root *root,
         u64 space_size;
         u64 avail;
         u64 used;
-        u64 to_add;
 
         used = space_info->bytes_used + space_info->bytes_reserved +
                 space_info->bytes_pinned + space_info->bytes_readonly;
@@ -3959,25 +3958,17 @@ static int can_overcommit(struct btrfs_root *root,
                        BTRFS_BLOCK_GROUP_RAID10))
                 avail >>= 1;
 
-        to_add = space_info->total_bytes;
-
         /*
          * If we aren't flushing all things, let us overcommit up to
          * 1/2th of the space. If we can flush, don't let us overcommit
          * too much, let it overcommit up to 1/8 of the space.
          */
         if (flush == BTRFS_RESERVE_FLUSH_ALL)
-                to_add >>= 3;
+                avail >>= 3;
         else
-                to_add >>= 1;
-
-        /*
-         * Limit the overcommit to the amount of free space we could possibly
-         * allocate for chunks.
-         */
-        to_add = min(avail, to_add);
+                avail >>= 1;
 
-        if (used + bytes < space_info->total_bytes + to_add)
+        if (used + bytes < space_info->total_bytes + avail)
                 return 1;
         return 0;
 }
@@ -4000,7 +3991,7 @@ static void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
                  */
                 btrfs_start_all_delalloc_inodes(root->fs_info, 0);
                 if (!current->journal_info)
-                        btrfs_wait_all_ordered_extents(root->fs_info, 0);
+                        btrfs_wait_all_ordered_extents(root->fs_info);
         }
 }
 
@@ -4030,7 +4021,7 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
         if (delalloc_bytes == 0) {
                 if (trans)
                         return;
-                btrfs_wait_all_ordered_extents(root->fs_info, 0);
+                btrfs_wait_all_ordered_extents(root->fs_info);
                 return;
         }
 
@@ -4058,7 +4049,7 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 
                 loops++;
                 if (wait_ordered && !trans) {
-                        btrfs_wait_all_ordered_extents(root->fs_info, 0);
+                        btrfs_wait_all_ordered_extents(root->fs_info);
                 } else {
                         time_left = schedule_timeout_killable(1);
                         if (time_left)
@@ -4465,7 +4456,6 @@ static void block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
                         space_info->bytes_may_use -= num_bytes;
                         trace_btrfs_space_reservation(fs_info, "space_info",
                                         space_info->flags, num_bytes, 0);
-                        space_info->reservation_progress++;
                         spin_unlock(&space_info->lock);
                 }
         }
@@ -4666,7 +4656,6 @@ static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
                 sinfo->bytes_may_use -= num_bytes;
                 trace_btrfs_space_reservation(fs_info, "space_info",
                                       sinfo->flags, num_bytes, 0);
-                sinfo->reservation_progress++;
                 block_rsv->reserved = block_rsv->size;
                 block_rsv->full = 1;
         }
@@ -5446,7 +5435,6 @@ static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
                         space_info->bytes_readonly += num_bytes;
                 cache->reserved -= num_bytes;
                 space_info->bytes_reserved -= num_bytes;
-                space_info->reservation_progress++;
         }
         spin_unlock(&cache->lock);
         spin_unlock(&space_info->lock);
@@ -6117,10 +6105,13 @@ enum btrfs_loop_type {
 /*
  * walks the btree of allocated extents and find a hole of a given size.
  * The key ins is changed to record the hole:
- * ins->objectid == block start
+ * ins->objectid == start position
  * ins->flags = BTRFS_EXTENT_ITEM_KEY
- * ins->offset == number of blocks
+ * ins->offset == the size of the hole.
  * Any available blocks before search_start are skipped.
+ *
+ * If there is no suitable free space, we will record the max size of
+ * the free space extent currently.
  */
 static noinline int find_free_extent(struct btrfs_root *orig_root,
                                      u64 num_bytes, u64 empty_size,
@@ -6133,6 +6124,7 @@ static noinline int find_free_extent(struct btrfs_root *orig_root,
         struct btrfs_block_group_cache *block_group = NULL;
         struct btrfs_block_group_cache *used_block_group;
         u64 search_start = 0;
+        u64 max_extent_size = 0;
         int empty_cluster = 2 * 1024 * 1024;
         struct btrfs_space_info *space_info;
         int loop = 0;
@@ -6292,7 +6284,10 @@ have_block_group:
                                 btrfs_get_block_group(used_block_group);
 
                         offset = btrfs_alloc_from_cluster(used_block_group,
-                          last_ptr, num_bytes, used_block_group->key.objectid);
+                                                last_ptr,
+                                                num_bytes,
+                                                used_block_group->key.objectid,
+                                                &max_extent_size);
                         if (offset) {
                                 /* we have a block, we're done */
                                 spin_unlock(&last_ptr->refill_lock);
@@ -6355,8 +6350,10 @@ refill_cluster:
                                  * cluster
                                  */
                                 offset = btrfs_alloc_from_cluster(block_group,
-                                                  last_ptr, num_bytes,
-                                                  search_start);
+                                                        last_ptr,
+                                                        num_bytes,
+                                                        search_start,
+                                                        &max_extent_size);
                                 if (offset) {
                                         /* we found one, proceed */
                                         spin_unlock(&last_ptr->refill_lock);
@@ -6391,13 +6388,18 @@ unclustered_alloc:
                 if (cached &&
                     block_group->free_space_ctl->free_space <
                     num_bytes + empty_cluster + empty_size) {
+                        if (block_group->free_space_ctl->free_space >
+                            max_extent_size)
+                                max_extent_size =
+                                        block_group->free_space_ctl->free_space;
                         spin_unlock(&block_group->free_space_ctl->tree_lock);
                         goto loop;
                 }
                 spin_unlock(&block_group->free_space_ctl->tree_lock);
 
                 offset = btrfs_find_space_for_alloc(block_group, search_start,
-                                                    num_bytes, empty_size);
+                                                    num_bytes, empty_size,
+                                                    &max_extent_size);
                 /*
                  * If we didn't find a chunk, and we haven't failed on this
                  * block group before, and this block group is in the middle of
@@ -6515,7 +6517,8 @@ loop:
                 ret = 0;
         }
 out:
-
+        if (ret == -ENOSPC)
+                ins->offset = max_extent_size;
         return ret;
 }
 
@@ -6573,8 +6576,8 @@ again:
                                flags);
 
         if (ret == -ENOSPC) {
-                if (!final_tried) {
-                        num_bytes = num_bytes >> 1;
+                if (!final_tried && ins->offset) {
+                        num_bytes = min(num_bytes >> 1, ins->offset);
                         num_bytes = round_down(num_bytes, root->sectorsize);
                         num_bytes = max(num_bytes, min_alloc_size);
                         if (num_bytes == min_alloc_size)