btrfs: update btrfs_space_info's bytes_may_use timely

[cascardo/linux.git] / fs / btrfs / file.c

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 5842423..3391f2a 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2675,6 +2675,7 @@ static long btrfs_fallocate(struct file *file, int mode,
 
        alloc_start = round_down(offset, blocksize);
        alloc_end = round_up(offset + len, blocksize);
+       cur_offset = alloc_start;
 
        /* Make sure we aren't being give some crap mode */
        if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
@@ -2767,7 +2768,6 @@ static long btrfs_fallocate(struct file *file, int mode,
 
        /* First, check if we exceed the qgroup limit */
        INIT_LIST_HEAD(&reserve_list);
-       cur_offset = alloc_start;
        while (1) {
                em = btrfs_get_extent(inode, NULL, 0, cur_offset,
                                      alloc_end - cur_offset, 0);
@@ -2794,6 +2794,14 @@ static long btrfs_fallocate(struct file *file, int mode,
                                        last_byte - cur_offset);
                        if (ret < 0)
                                break;
+               } else {
+                       /*
+                        * Do not need to reserve unwritten extent for this
+                        * range, free reserved data space first, otherwise
+                        * it'll result in false ENOSPC error.
+                        */
+                       btrfs_free_reserved_data_space(inode, cur_offset,
+                               last_byte - cur_offset);
                }
                free_extent_map(em);
                cur_offset = last_byte;
@@ -2811,6 +2819,9 @@ static long btrfs_fallocate(struct file *file, int mode,
                                        range->start,
                                        range->len, 1 << inode->i_blkbits,
                                        offset + len, &alloc_hint);
+               else
+                       btrfs_free_reserved_data_space(inode, range->start,
+                                                      range->len);
                list_del(&range->list);
                kfree(range);
        }
@@ -2845,18 +2856,11 @@ out_unlock:
        unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
                             &cached_state, GFP_KERNEL);
 out:
-       /*
-        * As we waited the extent range, the data_rsv_map must be empty
-        * in the range, as written data range will be released from it.
-        * And for prealloacted extent, it will also be released when
-        * its metadata is written.
-        * So this is completely used as cleanup.
-        */
-       btrfs_qgroup_free_data(inode, alloc_start, alloc_end - alloc_start);
        inode_unlock(inode);
        /* Let go of our reservation. */
-       btrfs_free_reserved_data_space(inode, alloc_start,
-                                      alloc_end - alloc_start);
+       if (ret != 0)
+               btrfs_free_reserved_data_space(inode, alloc_start,
+                                      alloc_end - cur_offset);
        return ret;
 }