Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull ceph fixes from Sage Weil:
 "There is a GFP flag fix from Mike Christie, an error code fix from
  Jan, and fixes for two unnecessary allocations (kmalloc and workqueue)
  from Ilya.  All are well tested.

  Ilya has one other fix on the way but it didn't get tested in time"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  libceph: eliminate unnecessary allocation in process_one_ticket()
  rbd: Fix error recovery in rbd_obj_read_sync()
  libceph: use memalloc flags for net IO
  rbd: use a single workqueue for all devices

drivers/block/rbd.c

@@ -342,7 +342,6 @@ struct rbd_device {
 
 	struct list_head	rq_queue;	/* incoming rq queue */
 	spinlock_t		lock;		/* queue, flags, open_count */
-	struct workqueue_struct	*rq_wq;
 	struct work_struct	rq_work;
 
 	struct rbd_image_header	header;
@@ -402,6 +401,8 @@ static struct kmem_cache	*rbd_segment_name_cache;
 static int rbd_major;
 static DEFINE_IDA(rbd_dev_id_ida);
 
+static struct workqueue_struct *rbd_wq;
+
 /*
  * Default to false for now, as single-major requires >= 0.75 version of
  * userspace rbd utility.
@@ -3452,7 +3453,7 @@ static void rbd_request_fn(struct request_queue *q)
 	}
 
 	if (queued)
-		queue_work(rbd_dev->rq_wq, &rbd_dev->rq_work);
+		queue_work(rbd_wq, &rbd_dev->rq_work);
 }
 
 /*
@@ -3532,7 +3533,7 @@ static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
 	page_count = (u32) calc_pages_for(offset, length);
 	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
 	if (IS_ERR(pages))
-		ret = PTR_ERR(pages);
+		return PTR_ERR(pages);
 
 	ret = -ENOMEM;
 	obj_request = rbd_obj_request_create(object_name, offset, length,
@@ -5242,16 +5243,9 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
 	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
 	set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
 
-	rbd_dev->rq_wq = alloc_workqueue("%s", WQ_MEM_RECLAIM, 0,
-					 rbd_dev->disk->disk_name);
-	if (!rbd_dev->rq_wq) {
-		ret = -ENOMEM;
-		goto err_out_mapping;
-	}
-
 	ret = rbd_bus_add_dev(rbd_dev);
 	if (ret)
-		goto err_out_workqueue;
+		goto err_out_mapping;
 
 	/* Everything's ready.  Announce the disk to the world. */
 
@@ -5263,9 +5257,6 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
 
 	return ret;
 
-err_out_workqueue:
-	destroy_workqueue(rbd_dev->rq_wq);
-	rbd_dev->rq_wq = NULL;
 err_out_mapping:
 	rbd_dev_mapping_clear(rbd_dev);
 err_out_disk:
@@ -5512,7 +5503,6 @@ static void rbd_dev_device_release(struct device *dev)
 {
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
-	destroy_workqueue(rbd_dev->rq_wq);
 	rbd_free_disk(rbd_dev);
 	clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
 	rbd_dev_mapping_clear(rbd_dev);
@@ -5716,11 +5706,21 @@ static int __init rbd_init(void)
 	if (rc)
 		return rc;
 
+	/*
+	 * The number of active work items is limited by the number of
+	 * rbd devices, so leave @max_active at default.
+	 */
+	rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
+	if (!rbd_wq) {
+		rc = -ENOMEM;
+		goto err_out_slab;
+	}
+
 	if (single_major) {
 		rbd_major = register_blkdev(0, RBD_DRV_NAME);
 		if (rbd_major < 0) {
 			rc = rbd_major;
-			goto err_out_slab;
+			goto err_out_wq;
 		}
 	}
 
@@ -5738,6 +5738,8 @@ static int __init rbd_init(void)
 err_out_blkdev:
 	if (single_major)
 		unregister_blkdev(rbd_major, RBD_DRV_NAME);
+err_out_wq:
+	destroy_workqueue(rbd_wq);
 err_out_slab:
 	rbd_slab_exit();
 	return rc;
@@ -5749,6 +5751,7 @@ static void __exit rbd_exit(void)
 	rbd_sysfs_cleanup();
 	if (single_major)
 		unregister_blkdev(rbd_major, RBD_DRV_NAME);
+	destroy_workqueue(rbd_wq);
 	rbd_slab_exit();
 }
 

net/ceph/auth_x.c

@@ -149,6 +149,7 @@ static int process_one_ticket(struct ceph_auth_client *ac,
 	struct ceph_crypto_key old_key;
 	void *ticket_buf = NULL;
 	void *tp, *tpend;
+	void **ptp;
 	struct ceph_timespec new_validity;
 	struct ceph_crypto_key new_session_key;
 	struct ceph_buffer *new_ticket_blob;
@@ -208,25 +209,19 @@ static int process_one_ticket(struct ceph_auth_client *ac,
 			goto out;
 		}
 		tp = ticket_buf;
-		dlen = ceph_decode_32(&tp);
+		ptp = &tp;
+		tpend = *ptp + dlen;
 	} else {
 		/* unencrypted */
-		ceph_decode_32_safe(p, end, dlen, bad);
-		ticket_buf = kmalloc(dlen, GFP_NOFS);
-		if (!ticket_buf) {
-			ret = -ENOMEM;
-			goto out;
-		}
-		tp = ticket_buf;
-		ceph_decode_need(p, end, dlen, bad);
-		ceph_decode_copy(p, ticket_buf, dlen);
+		ptp = p;
+		tpend = end;
 	}
-	tpend = tp + dlen;
+	ceph_decode_32_safe(ptp, tpend, dlen, bad);
 	dout(" ticket blob is %d bytes\n", dlen);
-	ceph_decode_need(&tp, tpend, 1 + sizeof(u64), bad);
-	blob_struct_v = ceph_decode_8(&tp);
-	new_secret_id = ceph_decode_64(&tp);
-	ret = ceph_decode_buffer(&new_ticket_blob, &tp, tpend);
+	ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
+	blob_struct_v = ceph_decode_8(ptp);
+	new_secret_id = ceph_decode_64(ptp);
+	ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
 	if (ret)
 		goto out;
 

net/ceph/messenger.c

@@ -484,7 +484,7 @@ static int ceph_tcp_connect(struct ceph_connection *con)
 			       IPPROTO_TCP, &sock);
 	if (ret)
 		return ret;
-	sock->sk->sk_allocation = GFP_NOFS;
+	sock->sk->sk_allocation = GFP_NOFS | __GFP_MEMALLOC;
 
 #ifdef CONFIG_LOCKDEP
 	lockdep_set_class(&sock->sk->sk_lock, &socket_class);
@@ -509,6 +509,9 @@ static int ceph_tcp_connect(struct ceph_connection *con)
 
 		return ret;
 	}
+
+	sk_set_memalloc(sock->sk);
+
 	con->sock = sock;
 	return 0;
 }
@@ -2769,8 +2772,11 @@ static void con_work(struct work_struct *work)
 {
 	struct ceph_connection *con = container_of(work, struct ceph_connection,
 						   work.work);
+	unsigned long pflags = current->flags;
 	bool fault;
 
+	current->flags |= PF_MEMALLOC;
+
 	mutex_lock(&con->mutex);
 	while (true) {
 		int ret;
@@ -2824,6 +2830,8 @@ static void con_work(struct work_struct *work)
 		con_fault_finish(con);
 
 	con->ops->put(con);
+
+	tsk_restore_flags(current, pflags, PF_MEMALLOC);
 }
 
 /*