Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target fixes from Nicholas Bellinger:
 "The highlights this merge window include:

   - Allow target fabric drivers to function as built-in.  (Roland)
   - Fix tcm_loop multi-TPG endpoint nexus bug.  (Hannes)
   - Move per device config_item_type into se_subsystem_api, allowing
     configfs attributes to be defined at module_init time.  (Jerome +
     nab)
   - Convert existing IBLOCK/FILEIO/RAMDISK/PSCSI/TCMU drivers to use
     external configfs attributes.  (nab)
   - A number of iser-target fixes related to active session + network
     portal shutdown stability during extended stress testing.  (Sagi +
     Slava)
   - Dynamic allocation of T10-PI contexts for iser-target, fixing a
     potentially bogus iscsi_np->tpg_np pointer reference in >= v3.14
     code.  (Sagi)
   - iser-target performance + scalability improvements.  (Sagi)
   - Fixes for SPC-4 Persistent Reservation AllRegistrants spec
     compliance.  (Ilias + James + nab)
   - Avoid potential short kern_sendmsg() in iscsi-target for now until
     Al's conversion to use msghdr iteration is merged post -rc1.
     (Viro)

  Also, Sagi has requested a number of iser-target patches (9) that
  address stability issues he's encountered during extended stress
  testing be considered for v3.10.y + v3.14.y code.  Given the amount of
  LOC involved, it will certainly require extra backporting effort.

  Apologies in advance to Greg-KH & Co on this.  Sagi and I will be
  working post-merge to ensure they each get applied correctly"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (53 commits)
  target: Allow AllRegistrants to re-RESERVE existing reservation
  uapi/linux/target_core_user.h: fix headers_install.sh badness
  iscsi-target: Fail connection on short sendmsg writes
  iscsi-target: nullify session in failed login sequence
  target: Avoid dropping AllRegistrants reservation during unregister
  target: Fix R_HOLDER bit usage for AllRegistrants
  iscsi-target: Drop left-over bogus iscsi_np->tpg_np
  iser-target: Fix wc->wr_id cast warning
  iser-target: Remove code duplication
  iser-target: Adjust log levels and prettify some prints
  iser-target: Use debug_level parameter to control logging level
  iser-target: Fix logout sequence
  iser-target: Don't wait for session commands from completion context
  iser-target: Reduce CQ lock contention by batch polling
  iser-target: Introduce isert_poll_budget
  iser-target: Remove an atomic operation from the IO path
  iser-target: Remove redundant call to isert_conn_terminate
  iser-target: Use single CQ for TX and RX
  iser-target: Centralize completion elements to a context
  iser-target: Cast wr_id with uintptr_t instead of unsinged long
  ...

drivers/infiniband/ulp/isert/ib_isert.h

@@ -4,9 +4,37 @@
 #include <rdma/ib_verbs.h>
 #include <rdma/rdma_cm.h>
 
+#define DRV_NAME	"isert"
+#define PFX		DRV_NAME ": "
+
+#define isert_dbg(fmt, arg...)				 \
+	do {						 \
+		if (unlikely(isert_debug_level > 2))	 \
+			printk(KERN_DEBUG PFX "%s: " fmt,\
+				__func__ , ## arg);	 \
+	} while (0)
+
+#define isert_warn(fmt, arg...)				\
+	do {						\
+		if (unlikely(isert_debug_level > 0))	\
+			pr_warn(PFX "%s: " fmt,         \
+				__func__ , ## arg);	\
+	} while (0)
+
+#define isert_info(fmt, arg...)				\
+	do {						\
+		if (unlikely(isert_debug_level > 1))	\
+			pr_info(PFX "%s: " fmt,         \
+				__func__ , ## arg);	\
+	} while (0)
+
+#define isert_err(fmt, arg...) \
+	pr_err(PFX "%s: " fmt, __func__ , ## arg)
+
 #define ISERT_RDMA_LISTEN_BACKLOG	10
 #define ISCSI_ISER_SG_TABLESIZE		256
 #define ISER_FASTREG_LI_WRID		0xffffffffffffffffULL
+#define ISER_BEACON_WRID               0xfffffffffffffffeULL
 
 enum isert_desc_type {
 	ISCSI_TX_CONTROL,
@@ -23,6 +51,7 @@ enum iser_ib_op_code {
 enum iser_conn_state {
 	ISER_CONN_INIT,
 	ISER_CONN_UP,
+	ISER_CONN_FULL_FEATURE,
 	ISER_CONN_TERMINATING,
 	ISER_CONN_DOWN,
 };
@@ -44,9 +73,6 @@ struct iser_tx_desc {
 	struct ib_sge	tx_sg[2];
 	int		num_sge;
 	struct isert_cmd *isert_cmd;
-	struct llist_node *comp_llnode_batch;
-	struct llist_node comp_llnode;
-	bool		llnode_active;
 	struct ib_send_wr send_wr;
 } __packed;
 
@@ -81,6 +107,12 @@ struct isert_data_buf {
 	enum dma_data_direction dma_dir;
 };
 
+enum {
+	DATA = 0,
+	PROT = 1,
+	SIG = 2,
+};
+
 struct isert_rdma_wr {
 	struct list_head	wr_list;
 	struct isert_cmd	*isert_cmd;
@@ -90,6 +122,7 @@ struct isert_rdma_wr {
 	int			send_wr_num;
 	struct ib_send_wr	*send_wr;
 	struct ib_send_wr	s_send_wr;
+	struct ib_sge		ib_sg[3];
 	struct isert_data_buf	data;
 	struct isert_data_buf	prot;
 	struct fast_reg_descriptor *fr_desc;
@@ -117,14 +150,15 @@ struct isert_device;
 struct isert_conn {
 	enum iser_conn_state	state;
 	int			post_recv_buf_count;
-	atomic_t		post_send_buf_count;
 	u32			responder_resources;
 	u32			initiator_depth;
+	bool			pi_support;
 	u32			max_sge;
 	char			*login_buf;
 	char			*login_req_buf;
 	char			*login_rsp_buf;
 	u64			login_req_dma;
+	int			login_req_len;
 	u64			login_rsp_dma;
 	unsigned int		conn_rx_desc_head;
 	struct iser_rx_desc	*conn_rx_descs;
@@ -132,13 +166,13 @@ struct isert_conn {
 	struct iscsi_conn	*conn;
 	struct list_head	conn_accept_node;
 	struct completion	conn_login_comp;
+	struct completion	login_req_comp;
 	struct iser_tx_desc	conn_login_tx_desc;
 	struct rdma_cm_id	*conn_cm_id;
 	struct ib_pd		*conn_pd;
 	struct ib_mr		*conn_mr;
 	struct ib_qp		*conn_qp;
 	struct isert_device	*conn_device;
-	struct work_struct	conn_logout_work;
 	struct mutex		conn_mutex;
 	struct completion	conn_wait;
 	struct completion	conn_wait_comp_err;
@@ -147,31 +181,38 @@ struct isert_conn {
 	int			conn_fr_pool_size;
 	/* lock to protect fastreg pool */
 	spinlock_t		conn_lock;
-#define ISERT_COMP_BATCH_COUNT	8
-	int			conn_comp_batch;
-	struct llist_head	conn_comp_llist;
-	bool                    disconnect;
+	struct work_struct	release_work;
+	struct ib_recv_wr       beacon;
+	bool                    logout_posted;
 };
 
 #define ISERT_MAX_CQ 64
 
-struct isert_cq_desc {
-	struct isert_device	*device;
-	int			cq_index;
-	struct work_struct	cq_rx_work;
-	struct work_struct	cq_tx_work;
+/**
+ * struct isert_comp - iSER completion context
+ *
+ * @device:     pointer to device handle
+ * @cq:         completion queue
+ * @wcs:        work completion array
+ * @active_qps: Number of active QPs attached
+ *              to completion context
+ * @work:       completion work handle
+ */
+struct isert_comp {
+	struct isert_device     *device;
+	struct ib_cq		*cq;
+	struct ib_wc		 wcs[16];
+	int                      active_qps;
+	struct work_struct	 work;
 };
 
 struct isert_device {
 	int			use_fastreg;
 	bool			pi_capable;
-	int			cqs_used;
 	int			refcount;
-	int			cq_active_qps[ISERT_MAX_CQ];
 	struct ib_device	*ib_device;
-	struct ib_cq		*dev_rx_cq[ISERT_MAX_CQ];
-	struct ib_cq		*dev_tx_cq[ISERT_MAX_CQ];
-	struct isert_cq_desc	*cq_desc;
+	struct isert_comp	*comps;
+	int                     comps_used;
 	struct list_head	dev_node;
 	struct ib_device_attr	dev_attr;
 	int			(*reg_rdma_mem)(struct iscsi_conn *conn,
@@ -182,6 +223,7 @@ struct isert_device {
 };
 
 struct isert_np {
+	struct iscsi_np         *np;
 	struct semaphore	np_sem;
 	struct rdma_cm_id	*np_cm_id;
 	struct mutex		np_accept_mutex;