Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..

1 files changed, 70 insertions, 34 deletions

diff --git a/include/linux/nvme-fc-driver.h b/include/linux/nvme-fc-driver.h
index f21471f7ee40..0db37158a61d 100644
--- a/include/linux/nvme-fc-driver.h
+++ b/include/linux/nvme-fc-driver.h
@@ -137,9 +137,9 @@ enum nvmefc_fcp_datadir {
  *             transferred. Should equal payload_length on success.
  * @rcv_rsplen: length, in bytes, of the FCP RSP IU received.
  * @status:    Completion status of the FCP operation. must be 0 upon success,
- *             NVME_SC_FC_xxx value upon failure. Note: this is NOT a
- *             reflection of the NVME CQE completion status. Only the status
- *             of the FCP operation at the NVME-FC level.
+ *             negative errno value upon failure (ex: -EIO). Note: this is
+ *             NOT a reflection of the NVME CQE completion status. Only the
+ *             status of the FCP operation at the NVME-FC level.
  */
 struct nvmefc_fcp_req {
 	void			*cmdaddr;
@@ -533,9 +533,6 @@ enum {
 					 * rsp as well
 					 */
 	NVMET_FCOP_RSP		= 4,	/* send rsp frame */
-	NVMET_FCOP_ABORT	= 5,	/* abort exchange via ABTS */
-	NVMET_FCOP_BA_ACC	= 6,	/* send BA_ACC */
-	NVMET_FCOP_BA_RJT	= 7,	/* send BA_RJT */
 };
 
 /**
@@ -572,8 +569,6 @@ enum {
  *     upon compeletion of the operation.  The nvmet-fc layer will also set a
  *     private pointer for its own use in the done routine.
  *
- * Note: the LLDD must never fail a NVMET_FCOP_ABORT request !!
- *
  * Values set by the NVMET-FC layer prior to calling the LLDD fcp_op
  * entrypoint.
  * @op:       Indicates the FCP IU operation to perform (see NVMET_FCOP_xxx)
@@ -655,6 +650,22 @@ enum {
 		 * on. The transport should pick a cpu to schedule the work
 		 * on.
 		 */
+	NVMET_FCTGTFEAT_CMD_IN_ISR = (1 << 2),
+		/* Bit 2: When 0, the LLDD is calling the cmd rcv handler
+		 * in a non-isr context, allowing the transport to finish
+		 * op completion in the calling context. When 1, the LLDD
+		 * is calling the cmd rcv handler in an ISR context,
+		 * requiring the transport to transition to a workqueue
+		 * for op completion.
+		 */
+	NVMET_FCTGTFEAT_OPDONE_IN_ISR = (1 << 3),
+		/* Bit 3: When 0, the LLDD is calling the op done handler
+		 * in a non-isr context, allowing the transport to finish
+		 * op completion in the calling context. When 1, the LLDD
+		 * is calling the op done handler in an ISR context,
+		 * requiring the transport to transition to a workqueue
+		 * for op completion.
+		 */
 };
 
 
@@ -725,12 +736,12 @@ struct nvmet_fc_target_port {
  *       be freed/released.
  *       Entrypoint is Mandatory.
  *
- * @fcp_op:  Called to perform a data transfer, transmit a response, or
- *       abort an FCP opertion. The nvmefc_tgt_fcp_req structure is the same
- *       LLDD-supplied exchange structure specified in the
- *       nvmet_fc_rcv_fcp_req() call made when the FCP CMD IU was received.
- *       The op field in the structure shall indicate the operation for
- *       the LLDD to perform relative to the io.
+ * @fcp_op:  Called to perform a data transfer or transmit a response.
+ *       The nvmefc_tgt_fcp_req structure is the same LLDD-supplied
+ *       exchange structure specified in the nvmet_fc_rcv_fcp_req() call
+ *       made when the FCP CMD IU was received. The op field in the
+ *       structure shall indicate the operation for the LLDD to perform
+ *       relative to the io.
  *         NVMET_FCOP_READDATA operation: the LLDD is to send the
  *           payload data (described by sglist) to the host in 1 or
  *           more FC sequences (preferrably 1).  Note: the fc-nvme layer
@@ -752,29 +763,31 @@ struct nvmet_fc_target_port {
  *           successfully, the LLDD is to update the nvmefc_tgt_fcp_req
  *           transferred_length field and may subsequently transmit the
  *           FCP_RSP iu payload (described by rspbuf, rspdma, rsplen).
- *           The LLDD is to await FCP_CONF reception to confirm the RSP
- *           reception by the host. The LLDD may retramsit the FCP_RSP iu
- *           if necessary per FC-NVME. Upon reception of FCP_CONF, or upon
- *           FCP_CONF failure, the LLDD is to set the nvmefc_tgt_fcp_req
- *           fcp_error field and consider the operation complete..
+ *           If FCP_CONF is supported, the LLDD is to await FCP_CONF
+ *           reception to confirm the RSP reception by the host. The LLDD
+ *           may retramsit the FCP_RSP iu if necessary per FC-NVME. Upon
+ *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
+ *           or upon success/failure of FCP_CONF if it is supported, the
+ *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
+ *           consider the operation complete.
  *         NVMET_FCOP_RSP: the LLDD is to transmit the FCP_RSP iu payload
- *           (described by rspbuf, rspdma, rsplen).  The LLDD is to await
- *           FCP_CONF reception to confirm the RSP reception by the host.
- *           The LLDD may retramsit the FCP_RSP iu if necessary per FC-NVME.
- *           Upon reception of FCP_CONF, or upon FCP_CONF failure, the
+ *           (described by rspbuf, rspdma, rsplen). If FCP_CONF is
+ *           supported, the LLDD is to await FCP_CONF reception to confirm
+ *           the RSP reception by the host. The LLDD may retramsit the
+ *           FCP_RSP iu if FCP_CONF is not received per FC-NVME. Upon
+ *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
+ *           or upon success/failure of FCP_CONF if it is supported, the
  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
- *           consider the operation complete..
- *         NVMET_FCOP_ABORT: the LLDD is to terminate the exchange
- *           corresponding to the fcp operation. The LLDD shall send
- *           ABTS and follow FC exchange abort-multi rules, including
- *           ABTS retries and possible logout.
+ *           consider the operation complete.
  *       Upon completing the indicated operation, the LLDD is to set the
  *       status fields for the operation (tranferred_length and fcp_error
- *       status) in the request, then all the "done" routine
- *       indicated in the fcp request.  Upon return from the "done"
- *       routine for either a NVMET_FCOP_RSP or NVMET_FCOP_ABORT operation
- *       the fc-nvme layer will not longer reference the fcp request,
- *       allowing the LLDD to free/release the fcp request.
+ *       status) in the request, then call the "done" routine
+ *       indicated in the fcp request. After the operation completes,
+ *       regardless of whether the FCP_RSP iu was successfully transmit,
+ *       the LLDD-supplied exchange structure must remain valid until the
+ *       transport calls the fcp_req_release() callback to return ownership
+ *       of the exchange structure back to the LLDD so that it may be used
+ *       for another fcp command.
  *       Note: when calling the done routine for READDATA or WRITEDATA
  *       operations, the fc-nvme layer may immediate convert, in the same
  *       thread and before returning to the LLDD, the fcp operation to
@@ -786,6 +799,22 @@ struct nvmet_fc_target_port {
  *       Returns 0 on success, -<errno> on failure (Ex: -EIO)
  *       Entrypoint is Mandatory.
  *
+ * @fcp_abort:  Called by the transport to abort an active command.
+ *       The command may be in-between operations (nothing active in LLDD)
+ *       or may have an active WRITEDATA operation pending. The LLDD is to
+ *       initiate the ABTS process for the command and return from the
+ *       callback. The ABTS does not need to be complete on the command.
+ *       The fcp_abort callback inherently cannot fail. After the
+ *       fcp_abort() callback completes, the transport will wait for any
+ *       outstanding operation (if there was one) to complete, then will
+ *       call the fcp_req_release() callback to return the command's
+ *       exchange context back to the LLDD.
+ *
+ * @fcp_req_release:  Called by the transport to return a nvmefc_tgt_fcp_req
+ *       to the LLDD after all operations on the fcp operation are complete.
+ *       This may be due to the command completing or upon completion of
+ *       abort cleanup.
+ *
  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
  *       supports for cpu affinitization.
  *       Value is Mandatory. Must be at least 1.
@@ -820,7 +849,11 @@ struct nvmet_fc_target_template {
 	int (*xmt_ls_rsp)(struct nvmet_fc_target_port *tgtport,
 				struct nvmefc_tgt_ls_req *tls_req);
 	int (*fcp_op)(struct nvmet_fc_target_port *tgtport,
-				struct nvmefc_tgt_fcp_req *);
+				struct nvmefc_tgt_fcp_req *fcpreq);
+	void (*fcp_abort)(struct nvmet_fc_target_port *tgtport,
+				struct nvmefc_tgt_fcp_req *fcpreq);
+	void (*fcp_req_release)(struct nvmet_fc_target_port *tgtport,
+				struct nvmefc_tgt_fcp_req *fcpreq);
 
 	u32	max_hw_queues;
 	u16	max_sgl_segments;
@@ -848,4 +881,7 @@ int nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *tgtport,
 			struct nvmefc_tgt_fcp_req *fcpreq,
 			void *cmdiubuf, u32 cmdiubuf_len);
 
+void nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *tgtport,
+			struct nvmefc_tgt_fcp_req *fcpreq);
+
 #endif /* _NVME_FC_DRIVER_H */