diff options
| author | Benjamin Marzinski <bmarzins@redhat.com> | 2012-11-06 00:49:28 -0600 |
|---|---|---|
| committer | Steven Whitehouse <swhiteho@redhat.com> | 2012-11-07 09:42:49 +0000 |
| commit | 3d1626889a64bd5a661544d582036a0a02104a60 (patch) | |
| tree | 7b5d43873e088346175d982fd8e840be586fcb5e /fs | |
| parent | 076f0faa764ab3a5a32fc726ae05e2de0e66151d (diff) | |
| download | lwn-3d1626889a64bd5a661544d582036a0a02104a60.tar.gz lwn-3d1626889a64bd5a661544d582036a0a02104a60.zip | |
GFS2: Don't call file_accessed() with a shared glock
file_accessed() was being called by gfs2_mmap() with a shared glock. If it
needed to update the atime, it was crashing because it dirtied the inode in
gfs2_dirty_inode() without holding an exclusive lock. gfs2_dirty_inode()
checked if the caller was already holding a glock, but it didn't make sure that
the glock was in the exclusive state. Now, instead of calling file_accessed()
while holding the shared lock in gfs2_mmap(), file_accessed() is called after
grabbing and releasing the glock to update the inode. If file_accessed() needs
to update the atime, it will grab an exclusive lock in gfs2_dirty_inode().
gfs2_dirty_inode() now also checks to make sure that if the calling process has
already locked the glock, it has an exclusive lock.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/gfs2/file.c | 12 | ||||
| -rw-r--r-- | fs/gfs2/super.c | 3 |
2 files changed, 7 insertions, 8 deletions
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 377a68dbd066..e056b4ce4877 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -516,15 +516,13 @@ static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) struct gfs2_holder i_gh; int error; - gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); - error = gfs2_glock_nq(&i_gh); - if (error == 0) { - file_accessed(file); - gfs2_glock_dq(&i_gh); - } - gfs2_holder_uninit(&i_gh); + error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, + &i_gh); if (error) return error; + /* grab lock to update inode */ + gfs2_glock_dq_uninit(&i_gh); + file_accessed(file); } vma->vm_ops = &gfs2_vm_ops; diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index bc737261f234..d6488674d916 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -810,7 +810,8 @@ static void gfs2_dirty_inode(struct inode *inode, int flags) return; } need_unlock = 1; - } + } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE)) + return; if (current->journal_info == NULL) { ret = gfs2_trans_begin(sdp, RES_DINODE, 0); |