[ 058/171] ext4: check dioread_nolock on remount

Greg Kroah-Hartman
2013-01-15T23:47:44Z

From: Jan Kara <jack@suse.cz>

commit 261cb20cb2f0737a247aaf08dff7eb065e3e5b66 upstream.

Currently we allow enabling dioread_nolock mount option on remount for
filesystems where blocksize < PAGE_CACHE_SIZE. This isn't really
supported so fix the bug by moving the check for blocksize !=
PAGE_CACHE_SIZE into parse_options(). Change the original PAGE_SIZE to
PAGE_CACHE_SIZE along the way because that's what we are really
interested in.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/ext4/super.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1599,9 +1599,7 @@ static int parse_options(char *options,
unsigned int *journal_ioprio,
int is_remount)
{
-#ifdef CONFIG_QUOTA
struct ext4_sb_info *sbi = EXT4_SB(sb);
-#endif
char *p;
substring_t args[MAX_OPT_ARGS];
int token;
@@ -1650,6 +1648,16 @@ static int parse_options(char *options,
}
}
#endif
+ if (test_opt(sb, DIOREAD_NOLOCK)) {
+ int blocksize =
+ BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
+
+ if (blocksize < PAGE_CACHE_SIZE) {
+ ext4_msg(sb, KERN_ERR, "can't mount with "
+ "dioread_nolock if block size != PAGE_SIZE");
+ return 0;
+ }
+ }
return 1;
}

@@ -3226,15 +3234,6 @@ static int ext4_fill_super(struct super_
clear_opt(sb, DELALLOC);
}

- blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
- if (test_opt(sb, DIOREAD_NOLOCK)) {
- if (blocksize < PAGE_SIZE) {
- ext4_msg(sb, KERN_ERR, "can't mount with "
- "dioread_nolock if block size != PAGE_SIZE");
- goto failed_mount;
- }
- }
-
sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
(test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);

@@ -3276,6 +3275,7 @@ static int ext4_fill_super(struct super_
if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
goto failed_mount;

+ blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
if (blocksize < EXT4_MIN_BLOCK_SIZE ||
blocksize > EXT4_MAX_BLOCK_SIZE) {
ext4_msg(sb, KERN_ERR,