2010-02-10 20:00:15

by Jiri Slaby

Subject: [PATCH 1/1] FS: btrfs, use helpers for rlimits

Make sure compiler won't do weird things with limits. E.g. fetching
them twice may return 2 different values after writable limits are
implemented.

I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd
or ACCESS_ONCE if not applicable.

Signed-off-by: Jiri Slaby <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: [email protected]
---
fs/btrfs/inode.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c41db6d..5aa0cef 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3256,8 +3256,7 @@ static int btrfs_setattr_size(struct inode *inode, struct iattr *attr)
return 0;

if (attr->ia_size > inode->i_size) {
- unsigned long limit;
- limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+ unsigned long limit = rlimit(RLIMIT_FSIZE);
if (attr->ia_size > inode->i_sb->s_maxbytes)
return -EFBIG;
if (limit != RLIM_INFINITY && attr->ia_size > limit) {
--
1.6.6.1

2010-02-10 20:03:05

by Chris Mason

Subject: Re: [PATCH 1/1] FS: btrfs, use helpers for rlimits

Thanks, I have this queued up for .34

-chris

On Wed, Feb 10, 2010 at 09:00:09PM +0100, Jiri Slaby wrote:
> Make sure compiler won't do weird things with limits. E.g. fetching
> them twice may return 2 different values after writable limits are
> implemented.
>
> I.e. either use rlimit helpers added in
> 3e10e716abf3c71bdb5d86b8f507f9e72236c9cd
> or ACCESS_ONCE if not applicable.
>
> Signed-off-by: Jiri Slaby <[email protected]>
> Cc: Chris Mason <[email protected]>
> Cc: [email protected]
> ---
> fs/btrfs/inode.c | 3 +--
> 1 files changed, 1 insertions(+), 2 deletions(-)
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index c41db6d..5aa0cef 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -3256,8 +3256,7 @@ static int btrfs_setattr_size(struct inode *inode, struct iattr *attr)
> return 0;
>
> if (attr->ia_size > inode->i_size) {
> - unsigned long limit;
> - limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
> + unsigned long limit = rlimit(RLIMIT_FSIZE);
> if (attr->ia_size > inode->i_sb->s_maxbytes)
> return -EFBIG;
> if (limit != RLIM_INFINITY && attr->ia_size > limit) {
> --
> 1.6.6.1
>