gfs2: Fix debugfs glocks dump

The switch to rhashtables (commit 88ffbf3e03) broke the debugfs glock
dump (/sys/kernel/debug/gfs2/<device>/glocks) for dumps bigger than a
single buffer: the right function for restarting an rhashtable iteration
from the beginning of the hash table is rhashtable_walk_enter;
rhashtable_walk_stop + rhashtable_walk_start will just resume from the
current position.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Cc: stable@vger.kernel.org # v4.3+
This commit is contained in:
Andreas Gruenbacher 2017-09-19 07:15:35 -05:00 committed by Bob Peterson
parent 46c1e79fee
commit 10201655b0

View File

@ -1945,13 +1945,9 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
{
struct gfs2_glock_iter *gi = seq->private;
loff_t n = *pos;
int ret;
if (gi->last_pos <= *pos)
n = (*pos - gi->last_pos);
ret = rhashtable_walk_start(&gi->hti);
if (ret)
rhashtable_walk_enter(&gl_hash_table, &gi->hti);
if (rhashtable_walk_start(&gi->hti) != 0)
return NULL;
do {
@ -1959,6 +1955,7 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
} while (gi->gl && n--);
gi->last_pos = *pos;
return gi->gl;
}
@ -1970,6 +1967,7 @@ static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
(*pos)++;
gi->last_pos = *pos;
gfs2_glock_iter_next(gi);
return gi->gl;
}
@ -1980,6 +1978,7 @@ static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
gi->gl = NULL;
rhashtable_walk_stop(&gi->hti);
rhashtable_walk_exit(&gi->hti);
}
static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
@ -2042,12 +2041,10 @@ static int __gfs2_glocks_open(struct inode *inode, struct file *file,
struct gfs2_glock_iter *gi = seq->private;
gi->sdp = inode->i_private;
gi->last_pos = 0;
seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
if (seq->buf)
seq->size = GFS2_SEQ_GOODSIZE;
gi->gl = NULL;
rhashtable_walk_enter(&gl_hash_table, &gi->hti);
}
return ret;
}
@ -2063,7 +2060,6 @@ static int gfs2_glocks_release(struct inode *inode, struct file *file)
struct gfs2_glock_iter *gi = seq->private;
gi->gl = NULL;
rhashtable_walk_exit(&gi->hti);
return seq_release_private(inode, file);
}