From e2f803481a84804811656a658c32176b7eec36e8 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Tue, 19 Sep 2017 07:15:35 -0500 Subject: [PATCH] gfs2: Fix debugfs glocks dump commit 10201655b085df8e000822e496e5d4016a167a36 upstream. The switch to rhashtables (commit 88ffbf3e03) broke the debugfs glock dump (/sys/kernel/debug/gfs2//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. The upstream commit doesn't directly apply to 4.9.y because 4.9.y doesn't have the following mainline commits: 92ecd73a887c4a2b94daf5fc35179d75d1c4ef95 gfs2: Deduplicate gfs2_{glocks,glstats}_open cc37a62785a584f4875788689f3fd1fa6e4eb291 gfs2: Replace rhashtable_walk_init with rhashtable_walk_enter Signed-off-by: Andreas Gruenbacher Signed-off-by: Bob Peterson Signed-off-by: Greg Kroah-Hartman --- fs/gfs2/glock.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 7bff6f4..f7cae16 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1836,13 +1836,9 @@ 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 { @@ -1850,6 +1846,7 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos) } while (gi->gl && n--); gi->last_pos = *pos; + return gi->gl; } @@ -1861,6 +1858,7 @@ 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; } @@ -1870,6 +1868,7 @@ 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) @@ -1932,12 +1931,10 @@ 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; - ret = rhashtable_walk_init(&gl_hash_table, &gi->hti, GFP_KERNEL); } return ret; } @@ -1948,7 +1945,6 @@ 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); } @@ -1960,12 +1956,10 @@ static int gfs2_glstats_open(struct inode *inode, struct file *file) struct seq_file *seq = file->private_data; 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; - ret = rhashtable_walk_init(&gl_hash_table, &gi->hti, GFP_KERNEL); } return ret; } -- 2.7.4