ext4: Convert s_blocks_count to s_blocks_count_lo

Convert s_blocks_count to s_blocks_count_lo
This helps in finding BUGs due to direct partial access of
these split 64 bit values

Also fix direct partial access in ext4 code

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index f9cb64c..11e80f0 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2667,7 +2667,7 @@ static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
 
        if (test_opt(sb, MINIX_DF)) {
                sbi->s_overhead_last = 0;
-       } else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
+       } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
                unsigned long ngroups = sbi->s_groups_count, i;
                ext4_fsblk_t overhead = 0;
                smp_rmb();
@@ -2702,7 +2702,7 @@ static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
                overhead += ngroups * (2 + sbi->s_itb_per_group);
                sbi->s_overhead_last = overhead;
                smp_wmb();
-               sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
+               sbi->s_blocks_last = ext4_blocks_count(es);
        }
 
        buf->f_type = EXT4_SUPER_MAGIC;

diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h
index f5d57c7..d30d079 100644 (file)
--- a/include/linux/ext4_fs.h
+++ b/include/linux/ext4_fs.h
@@ -501,7 +501,7 @@ do {                                                                               \
  */
 struct ext4_super_block {
 /*00*/ __le32  s_inodes_count;         /* Inodes count */
-       __le32  s_blocks_count;         /* Blocks count */
+       __le32  s_blocks_count_lo;      /* Blocks count */
        __le32  s_r_blocks_count;       /* Reserved blocks count */
        __le32  s_free_blocks_count;    /* Free blocks count */
 /*10*/ __le32  s_free_inodes_count;    /* Free inodes count */
@@ -981,7 +981,7 @@ extern void ext4_inode_table_set(struct super_block *sb,
 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
 {
        return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
-               le32_to_cpu(es->s_blocks_count);
+               le32_to_cpu(es->s_blocks_count_lo);
 }
 
 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
@@ -999,7 +999,7 @@ static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
                                         ext4_fsblk_t blk)
 {
-       es->s_blocks_count = cpu_to_le32((u32)blk);
+       es->s_blocks_count_lo = cpu_to_le32((u32)blk);
        es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
 }