Commit 7b08fc62 authored by Steven Whitehouse's avatar Steven Whitehouse

[GFS2] Fix an oops in glock dumping

This fixes an oops which was occurring during glock dumping due to the
seq file code not taking a reference to the glock. Also this fixes a
memory leak which occurred in certain cases, in turn preventing the
filesystem from unmounting.
Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
parent afd0942d
......@@ -46,7 +46,6 @@ struct glock_iter {
int hash; /* hash bucket index */
struct gfs2_sbd *sdp; /* incore superblock */
struct gfs2_glock *gl; /* current glock struct */
struct hlist_head *hb_list; /* current hash bucket ptr */
struct seq_file *seq; /* sequence file for debugfs */
char string[512]; /* scratch space */
};
......@@ -1990,47 +1989,38 @@ int __init gfs2_glock_init(void)
static int gfs2_glock_iter_next(struct glock_iter *gi)
{
struct gfs2_glock *gl;
read_lock(gl_lock_addr(gi->hash));
while (1) {
if (!gi->hb_list) { /* If we don't have a hash bucket yet */
gi->hb_list = &gl_hash_table[gi->hash].hb_list;
if (hlist_empty(gi->hb_list)) {
read_unlock(gl_lock_addr(gi->hash));
gi->hash++;
read_lock(gl_lock_addr(gi->hash));
gi->hb_list = NULL;
if (gi->hash >= GFS2_GL_HASH_SIZE) {
read_unlock(gl_lock_addr(gi->hash));
return 1;
}
else
continue;
}
if (!hlist_empty(gi->hb_list)) {
gi->gl = list_entry(gi->hb_list->first,
struct gfs2_glock,
gl_list);
}
} else {
if (gi->gl->gl_list.next == NULL) {
read_unlock(gl_lock_addr(gi->hash));
gi->hash++;
read_lock(gl_lock_addr(gi->hash));
gi->hb_list = NULL;
continue;
}
gi->gl = list_entry(gi->gl->gl_list.next,
struct gfs2_glock, gl_list);
}
gl = gi->gl;
if (gl) {
gi->gl = hlist_entry(gl->gl_list.next, struct gfs2_glock,
gl_list);
if (gi->gl)
break;
gfs2_glock_hold(gi->gl);
}
read_unlock(gl_lock_addr(gi->hash));
if (gl)
gfs2_glock_put(gl);
while(gi->gl == NULL) {
gi->hash++;
if (gi->hash >= GFS2_GL_HASH_SIZE)
return 1;
read_lock(gl_lock_addr(gi->hash));
gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first,
struct gfs2_glock, gl_list);
if (gi->gl)
gfs2_glock_hold(gi->gl);
read_unlock(gl_lock_addr(gi->hash));
}
return 0;
}
static void gfs2_glock_iter_free(struct glock_iter *gi)
{
if (gi->gl)
gfs2_glock_put(gi->gl);
kfree(gi);
}
......@@ -2044,12 +2034,17 @@ static struct glock_iter *gfs2_glock_iter_init(struct gfs2_sbd *sdp)
gi->sdp = sdp;
gi->hash = 0;
gi->gl = NULL;
gi->hb_list = NULL;
gi->seq = NULL;
memset(gi->string, 0, sizeof(gi->string));
if (gfs2_glock_iter_next(gi)) {
read_lock(gl_lock_addr(gi->hash));
gi->gl = hlist_entry(gl_hash_table[gi->hash].hb_list.first,
struct gfs2_glock, gl_list);
if (gi->gl)
gfs2_glock_hold(gi->gl);
read_unlock(gl_lock_addr(gi->hash));
if (!gi->gl && gfs2_glock_iter_next(gi)) {
gfs2_glock_iter_free(gi);
return NULL;
}
......@@ -2066,7 +2061,7 @@ static void *gfs2_glock_seq_start(struct seq_file *file, loff_t *pos)
if (!gi)
return NULL;
while (n--) {
while(n--) {
if (gfs2_glock_iter_next(gi)) {
gfs2_glock_iter_free(gi);
return NULL;
......@@ -2093,7 +2088,9 @@ static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr,
static void gfs2_glock_seq_stop(struct seq_file *file, void *iter_ptr)
{
/* nothing for now */
struct glock_iter *gi = iter_ptr;
if (gi)
gfs2_glock_iter_free(gi);
}
static int gfs2_glock_seq_show(struct seq_file *file, void *iter_ptr)
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment