cleanup-gfp-flags-inside-resize-path

   1 ext4: cleanup GFP flags inside resize path
   2
   3 From: Dmitry Monakhov <dmonakhov@openvz.org>
   4
   5 We must use GFP_NOFS instead GFP_KERNEL inside ext4_mb_add_groupinfo
   6 and ext4_calculate_overhead() because they are called from inside a
   7 journal transaction. Call trace:
   8
   9 ioctl
  10  ->ext4_group_add
  11    ->journal_start
  12    ->ext4_setup_new_descs
  13      ->ext4_mb_add_groupinfo -> GFP_KERNEL
  14    ->ext4_flex_group_add
  15      ->ext4_update_super
  16        ->ext4_calculate_overhead  -> GFP_KERNEL
  17    ->journal_stop
  18
  19 Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
  20 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  21 ---
  22  fs/ext4/mballoc.c |    6 +++---
  23  fs/ext4/super.c   |    2 +-
  24  2 files changed, 4 insertions(+), 4 deletions(-)
  25
  26 diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
  27 index dbfe15c..654e70d 100644
  28 --- a/fs/ext4/mballoc.c
  29 +++ b/fs/ext4/mballoc.c
  30 @@ -2385,7 +2385,7 @@ int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
  31         if (group % EXT4_DESC_PER_BLOCK(sb) == 0) {
  32                 metalen = sizeof(*meta_group_info) <<
  33                         EXT4_DESC_PER_BLOCK_BITS(sb);
  34 -               meta_group_info = kmalloc(metalen, GFP_KERNEL);
  35 +               meta_group_info = kmalloc(metalen, GFP_NOFS);
  36                 if (meta_group_info == NULL) {
  37                         ext4_msg(sb, KERN_ERR, "can't allocate mem "
  38                                  "for a buddy group");
  39 @@ -2399,7 +2399,7 @@ int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
  40                 sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)];
  41         i = group & (EXT4_DESC_PER_BLOCK(sb) - 1);
  42
  43 -       meta_group_info[i] = kmem_cache_zalloc(cachep, GFP_KERNEL);
  44 +       meta_group_info[i] = kmem_cache_zalloc(cachep, GFP_NOFS);
  45         if (meta_group_info[i] == NULL) {
  46                 ext4_msg(sb, KERN_ERR, "can't allocate buddy mem");
  47                 goto exit_group_info;
  48 @@ -2428,7 +2428,7 @@ int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
  49         {
  50                 struct buffer_head *bh;
  51                 meta_group_info[i]->bb_bitmap =
  52 -                       kmalloc(sb->s_blocksize, GFP_KERNEL);
  53 +                       kmalloc(sb->s_blocksize, GFP_NOFS);
  54                 BUG_ON(meta_group_info[i]->bb_bitmap == NULL);
  55                 bh = ext4_read_block_bitmap(sb, group);
  56                 BUG_ON(bh == NULL);
  57 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
  58 index 2c9e686..5f6cab8 100644
  59 --- a/fs/ext4/super.c
  60 +++ b/fs/ext4/super.c
  61 @@ -3310,7 +3310,7 @@ int ext4_calculate_overhead(struct super_block *sb)
  62         struct ext4_super_block *es = sbi->s_es;
  63         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
  64         ext4_fsblk_t overhead = 0;
  65 -       char *buf = (char *) get_zeroed_page(GFP_KERNEL);
  66 +       char *buf = (char *) get_zeroed_page(GFP_NOFS);
  67
  68         if (!buf)
  69                 return -ENOMEM;
  70 --
  71 1.7.1
  72
  73