ext4-Signed-arithematic-fix.patch

   1 ext4: Signed arithematic fix
   2
   3 From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   4
   5 This patch converts some usage of ext4_fsblk_t to s64.  This is needed
   6 so that some of the sign conversion works as expected in if loops.
   7
   8 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   9 Signed-off-by: Mingming Cao <cmm@us.ibm.com>
  10 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
  11
  12 diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
  13 index 87b198c..e4274aa 100644
  14 --- a/fs/ext4/balloc.c
  15 +++ b/fs/ext4/balloc.c
  16 @@ -1603,10 +1603,10 @@ out:
  17  }
  18
  19  int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  20 -                                               ext4_fsblk_t nblocks)
  21 +                                               s64 nblocks)
  22  {
  23         s64 free_blocks, dirty_blocks;
  24 -       ext4_fsblk_t root_blocks = 0;
  25 +       s64 root_blocks = 0;
  26         struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
  27         struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
  28
  29 @@ -1631,7 +1631,7 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  30         /* Check whether we have space after
  31          * accounting for current dirty blocks
  32          */
  33 -       if (free_blocks < ((s64)(root_blocks + nblocks) + dirty_blocks))
  34 +       if (free_blocks < ((root_blocks + nblocks) + dirty_blocks))
  35                 /* we don't have free space */
  36                 return -ENOSPC;
  37
  38 @@ -1650,10 +1650,10 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  39   * On success, return nblocks
  40   */
  41  ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
  42 -                                               ext4_fsblk_t nblocks)
  43 +                                               s64 nblocks)
  44  {
  45 -       ext4_fsblk_t free_blocks, dirty_blocks;
  46 -       ext4_fsblk_t root_blocks = 0;
  47 +       s64 free_blocks, dirty_blocks;
  48 +       s64 root_blocks = 0;
  49         struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
  50         struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
  51
  52 @@ -1667,14 +1667,15 @@ ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
  53
  54         if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
  55                                                 EXT4_FREEBLOCKS_WATERMARK) {
  56 -               free_blocks  = percpu_counter_sum_positive(fbc);
  57 -               dirty_blocks = percpu_counter_sum_positive(dbc);
  58 +               free_blocks  = percpu_counter_sum(fbc);
  59 +               dirty_blocks = percpu_counter_sum(dbc);
  60         }
  61         if (free_blocks <= (root_blocks + dirty_blocks))
  62                 /* we don't have free space */
  63                 return 0;
  64 +
  65         if (free_blocks - (root_blocks + dirty_blocks) < nblocks)
  66 -               return free_blocks - root_blocks;
  67 +               return free_blocks - (root_blocks + dirty_blocks);
  68         return nblocks;
  69  }
  70
  71 diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
  72 index 0154c2d..e13b9de 100644
  73 --- a/fs/ext4/ext4.h
  74 +++ b/fs/ext4/ext4.h
  75 @@ -983,10 +983,9 @@ extern ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
  76                                         unsigned long *count, int *errp);
  77  extern ext4_fsblk_t ext4_old_new_blocks(handle_t *handle, struct inode *inode,
  78                         ext4_fsblk_t goal, unsigned long *count, int *errp);
  79 -extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  80 -                                               ext4_fsblk_t nblocks);
  81 +extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
  82  extern ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
  83 -                                               ext4_fsblk_t nblocks);
  84 +                                        s64 nblocks);
  85  extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
  86                         ext4_fsblk_t block, unsigned long count, int metadata);
  87  extern void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,