Commit 17f8dc2d authored by Xiubo Li's avatar Xiubo Li Committed by Ilya Dryomov
Browse files

ceph: switch to use cap_delay_lock for the unlink delay list 

The same list item will be used in both cap_delay_list and
cap_unlink_delay_list, so it's buggy to use two different locks
to protect them.

Cc: stable@vger.kernel.org
Fixes: dbc347ef ("ceph: add ceph_cap_unlink_work to fire check_caps() immediately")
Link: https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/AODC76VXRAMXKLFDCTK4TKFDDPWUSCN5


Reported-by: default avatarMarc Ruhmann <ruhmann@luis.uni-hannover.de>
Signed-off-by: default avatarXiubo Li <xiubli@redhat.com>
Reviewed-by: default avatarIlya Dryomov <idryomov@gmail.com>
Tested-by: default avatarMarc Ruhmann <ruhmann@luis.uni-hannover.de>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent b372e96b

fs/ceph/caps.c

+2 −2
Original line number Diff line number Diff line
@@ -4783,13 +4783,13 @@ int ceph_drop_caps_for_unlink(struct inode *inode) 


			doutc(mdsc->fsc->client, "%p %llx.%llx\n", inode,

			      ceph_vinop(inode));

			spin_lock(&mdsc->cap_unlink_delay_lock);

			spin_lock(&mdsc->cap_delay_lock);

			ci->i_ceph_flags |= CEPH_I_FLUSH;

			if (!list_empty(&ci->i_cap_delay_list))

				list_del_init(&ci->i_cap_delay_list);

			list_add_tail(&ci->i_cap_delay_list,

				      &mdsc->cap_unlink_delay_list);

			spin_unlock(&mdsc->cap_unlink_delay_lock);

			spin_unlock(&mdsc->cap_delay_lock);



			/*

			 * Fire the work immediately, because the MDS maybe

fs/ceph/mds_client.c

+4 −5
Original line number Diff line number Diff line
@@ -2504,7 +2504,7 @@ static void ceph_cap_unlink_work(struct work_struct *work) 
	struct ceph_client *cl = mdsc->fsc->client;



	doutc(cl, "begin\n");

	spin_lock(&mdsc->cap_unlink_delay_lock);

	spin_lock(&mdsc->cap_delay_lock);

	while (!list_empty(&mdsc->cap_unlink_delay_list)) {

		struct ceph_inode_info *ci;

		struct inode *inode;
@@ -2516,15 +2516,15 @@ static void ceph_cap_unlink_work(struct work_struct *work) 


		inode = igrab(&ci->netfs.inode);

		if (inode) {

			spin_unlock(&mdsc->cap_unlink_delay_lock);

			spin_unlock(&mdsc->cap_delay_lock);

			doutc(cl, "on %p %llx.%llx\n", inode,

			      ceph_vinop(inode));

			ceph_check_caps(ci, CHECK_CAPS_FLUSH);

			iput(inode);

			spin_lock(&mdsc->cap_unlink_delay_lock);

			spin_lock(&mdsc->cap_delay_lock);

		}

	}

	spin_unlock(&mdsc->cap_unlink_delay_lock);

	spin_unlock(&mdsc->cap_delay_lock);

	doutc(cl, "done\n");

}
@@ -5404,7 +5404,6 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc) 
	INIT_LIST_HEAD(&mdsc->cap_wait_list);

	spin_lock_init(&mdsc->cap_delay_lock);

	INIT_LIST_HEAD(&mdsc->cap_unlink_delay_list);

	spin_lock_init(&mdsc->cap_unlink_delay_lock);

	INIT_LIST_HEAD(&mdsc->snap_flush_list);

	spin_lock_init(&mdsc->snap_flush_lock);

	mdsc->last_cap_flush_tid = 1;

fs/ceph/mds_client.h

+1 −2
Original line number Diff line number Diff line
@@ -461,9 +461,8 @@ struct ceph_mds_client { 
	struct delayed_work    delayed_work;  /* delayed work */

	unsigned long    last_renew_caps;  /* last time we renewed our caps */

	struct list_head cap_delay_list;   /* caps with delayed release */

	spinlock_t       cap_delay_lock;   /* protects cap_delay_list */

	struct list_head cap_unlink_delay_list;  /* caps with delayed release for unlink */

	spinlock_t       cap_unlink_delay_lock;  /* protects cap_unlink_delay_list */

	spinlock_t       cap_delay_lock;   /* protects cap_delay_list and cap_unlink_delay_list */

	struct list_head snap_flush_list;  /* cap_snaps ready to flush */

	spinlock_t       snap_flush_lock;