2012-12-13 21:40:49

by Jan Kara

Subject: [PATCH] ext4: Check dioread_nolock on remount

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 <[email protected]>
---
fs/ext4/super.c | 22 +++++++++++-----------
1 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 80928f7..9753ed2 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1650,9 +1650,7 @@ static int parse_options(char *options, struct super_block *sb,
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;
@@ -1701,6 +1699,16 @@ static int parse_options(char *options, struct super_block *sb,
}
}
#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;
}

@@ -3446,15 +3454,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
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;
- }
- }

2012-12-17 15:43:57

by Eric Sandeen

Subject: Re: [PATCH] ext4: Check dioread_nolock on remount

On 12/13/12 3:40 PM, Jan Kara wrote:
> 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 <[email protected]>

Looks good to me,

Reviewed-by: Eric Sandeen <[email protected]>

> ---
> fs/ext4/super.c | 22 +++++++++++-----------
> 1 files changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 80928f7..9753ed2 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1650,9 +1650,7 @@ static int parse_options(char *options, struct super_block *sb,
> 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;
> @@ -1701,6 +1699,16 @@ static int parse_options(char *options, struct super_block *sb,
> }
> }
> #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;
> }
>
> @@ -3446,15 +3454,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
> 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);
>
> @@ -3496,6 +3495,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
> 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,
>

2012-12-20 05:08:01

by Theodore Ts'o

Subject: Re: [PATCH] ext4: Check dioread_nolock on remount

On Thu, Dec 13, 2012 at 10:40:42PM +0100, Jan Kara wrote:
> 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 <[email protected]>

Applied, thanks.

- Ted