From 74793c719ed106bf71c02dd92057d7bba3423fa5 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Fri, 4 Mar 2022 10:31:49 +1000 Subject: [PATCH] cifs: fix handlecache and multiuser In multiuser each individual user has their own tcon structure for the share and thus their own handle for a cached directory. When we umount such a share we much make sure to release the pinned down dentry for each such tcon and not just the master tcon. Otherwise we will get nasty warnings on umount that dentries are still in use: [ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/} still in use\ (2) [unmount of cifs cifs] ... [ 3459.590492] Call Trace: [ 3459.590500] d_walk+0x61/0x2a0 [ 3459.590518] ? shrink_lock_dentry.part.0+0xe0/0xe0 [ 3459.590526] shrink_dcache_for_umount+0x49/0x110 [ 3459.590535] generic_shutdown_super+0x1a/0x110 [ 3459.590542] kill_anon_super+0x14/0x30 [ 3459.590549] cifs_kill_sb+0xf5/0x104 [cifs] [ 3459.590773] deactivate_locked_super+0x36/0xa0 [ 3459.590782] cleanup_mnt+0x131/0x190 [ 3459.590789] task_work_run+0x5c/0x90 [ 3459.590798] exit_to_user_mode_loop+0x151/0x160 [ 3459.590809] exit_to_user_mode_prepare+0x83/0xd0 [ 3459.590818] syscall_exit_to_user_mode+0x12/0x30 [ 3459.590828] do_syscall_64+0x48/0x90 [ 3459.590833] entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: Ronnie Sahlberg Acked-by: Paulo Alcantara (SUSE) Cc: stable@vger.kernel.org Signed-off-by: Steve French --- fs/cifs/cifsfs.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index c8df044dfbe5..e1bfa419f623 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -254,6 +254,9 @@ static void cifs_kill_sb(struct super_block *sb) struct cifs_sb_info *cifs_sb = CIFS_SB(sb); struct cifs_tcon *tcon; struct cached_fid *cfid; + struct rb_root *root = &cifs_sb->tlink_tree; + struct rb_node *node; + struct tcon_link *tlink; /* * We ned to release all dentries for the cached directories @@ -263,17 +266,21 @@ static void cifs_kill_sb(struct super_block *sb) dput(cifs_sb->root); cifs_sb->root = NULL; } - tcon = cifs_sb_master_tcon(cifs_sb); - if (tcon) { + spin_lock(&cifs_sb->tlink_tree_lock); + node = rb_first(root); + while (node != NULL) { + tlink = rb_entry(node, struct tcon_link, tl_rbnode); + tcon = tlink_tcon(tlink); cfid = &tcon->crfid; mutex_lock(&cfid->fid_mutex); if (cfid->dentry) { - dput(cfid->dentry); cfid->dentry = NULL; } mutex_unlock(&cfid->fid_mutex); + node = rb_next(node); } + spin_unlock(&cifs_sb->tlink_tree_lock); kill_anon_super(sb); cifs_umount(cifs_sb); -- 2.34.1