GFS2: Fix lseek after SEEK_DATA, SEEK_HOLE have been added

We need to take the inode's glock whenever the inode's size
is referenced, otherwise it might not be uptodate. Even
though generic_file_llseek_unlocked() doesn't implement
SEEK_DATA, SEEK_HOLE directly, it does reference the inode's
size in those cases, so we need to add them to the list
of origins which need the glock.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
This commit is contained in:
Steven Whitehouse 2011-08-23 10:19:25 +01:00
parent 9a63edd12b
commit 9453615a1a

View File

@ -59,15 +59,24 @@ static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
struct gfs2_holder i_gh;
loff_t error;
if (origin == 2) {
switch (origin) {
case SEEK_END: /* These reference inode->i_size */
case SEEK_DATA:
case SEEK_HOLE:
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (!error) {
error = generic_file_llseek_unlocked(file, offset, origin);
gfs2_glock_dq_uninit(&i_gh);
}
} else
break;
case SEEK_CUR:
case SEEK_SET:
error = generic_file_llseek_unlocked(file, offset, origin);
break;
default:
error = -EINVAL;
}
return error;
}