ext4: Signed arithmetic fix

This patch converts some usage of ext4_fsblk_t to s64.  This is needed
so that some of the sign conversion works as expected in if loops.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 10 insertions, 9 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index edef0023e6e6..a425e78c73eb 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -1603,10 +1603,10 @@ out:
 }
 
 int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
-                                                ext4_fsblk_t nblocks)
+                                                s64 nblocks)
 {
         s64 free_blocks, dirty_blocks;
-        ext4_fsblk_t root_blocks = 0;
+        s64 root_blocks = 0;
         struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
         struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
 
@@ -1631,7 +1631,7 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
         /* Check whether we have space after
          * accounting for current dirty blocks
          */
-        if (free_blocks < ((s64)(root_blocks + nblocks) + dirty_blocks))
+        if (free_blocks < ((root_blocks + nblocks) + dirty_blocks))
                 /* we don't have free space */
                 return -ENOSPC;
 
@@ -1650,10 +1650,10 @@ int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
  * On success, return nblocks
  */
 ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
-                                                ext4_fsblk_t nblocks)
+                                                s64 nblocks)
 {
-        ext4_fsblk_t free_blocks, dirty_blocks;
-        ext4_fsblk_t root_blocks = 0;
+        s64 free_blocks, dirty_blocks;
+        s64 root_blocks = 0;
         struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
         struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
 
@@ -1667,14 +1667,15 @@ ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
 
         if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
                                                 EXT4_FREEBLOCKS_WATERMARK) {
-                free_blocks  = percpu_counter_sum_positive(fbc);
-                dirty_blocks = percpu_counter_sum_positive(dbc);
+                free_blocks  = percpu_counter_sum(fbc);
+                dirty_blocks = percpu_counter_sum(dbc);
         }
         if (free_blocks <= (root_blocks + dirty_blocks))
                 /* we don't have free space */
                 return 0;
+
         if (free_blocks - (root_blocks + dirty_blocks) < nblocks)
-                return free_blocks - root_blocks;
+                return free_blocks - (root_blocks + dirty_blocks);
         return nblocks;
 }