diff mbox series

[09/24] mpi3mr: add support for recovering controller

Message ID 20201222101156.98308-10-kashyap.desai@broadcom.com
State New
Headers show
Series Introducing mpi3mr driver | expand

Commit Message

Kashyap Desai Dec. 22, 2020, 10:11 a.m. UTC
Added h/w defined process of doing controller reset.
The driver on detection of firmware fault or any kind of unresponsiveness in
the controller (Any admin command time outs) results in resetting the controller.
The primary reset mechanisms used are either soft reset or diag fault reset.
Reset is performed if the host sets the ResetAction field in the HostDiagnostic
register to a 001b (Soft Reset) or 007b(diag fault reset).
The driver after successfully resetting the controller reinitialize the
controller by going through start of the day controller initialization procedures.
The pending I/Os during the reset are returned back to SML for retry.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: sathya.prakash@broadcom.com
---
 drivers/scsi/mpi3mr/mpi3mr.h    |  22 +-
 drivers/scsi/mpi3mr/mpi3mr_fw.c | 416 +++++++++++++++++++++++++++++---
 drivers/scsi/mpi3mr/mpi3mr_os.c |  93 ++++++-
 3 files changed, 488 insertions(+), 43 deletions(-)

Comments

Hannes Reinecke March 1, 2021, 6:56 a.m. UTC | #1
On 12/22/20 11:11 AM, Kashyap Desai wrote:
> Added h/w defined process of doing controller reset.

> The driver on detection of firmware fault or any kind of unresponsiveness in

> the controller (Any admin command time outs) results in resetting the controller.

> The primary reset mechanisms used are either soft reset or diag fault reset.

> Reset is performed if the host sets the ResetAction field in the HostDiagnostic

> register to a 001b (Soft Reset) or 007b(diag fault reset).

> The driver after successfully resetting the controller reinitialize the

> controller by going through start of the day controller initialization procedures.

> The pending I/Os during the reset are returned back to SML for retry.

> 

> Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>

> Cc: sathya.prakash@broadcom.com

> ---

>   drivers/scsi/mpi3mr/mpi3mr.h    |  22 +-

>   drivers/scsi/mpi3mr/mpi3mr_fw.c | 416 +++++++++++++++++++++++++++++---

>   drivers/scsi/mpi3mr/mpi3mr_os.c |  93 ++++++-

>   3 files changed, 488 insertions(+), 43 deletions(-)

> 

Reviewed-by: Hannes Reinecke <hare@suse.de>


Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer
diff mbox series

Patch

diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
index 1f70a67d7868..f60749c94c9a 100644
--- a/drivers/scsi/mpi3mr/mpi3mr.h
+++ b/drivers/scsi/mpi3mr/mpi3mr.h
@@ -98,6 +98,7 @@  extern struct list_head mrioc_list;
 #define MPI3MR_INTADMCMD_TIMEOUT		10
 #define MPI3MR_PORTENABLE_TIMEOUT		300
 #define MPI3MR_RESETTM_TIMEOUT			30
+#define MPI3MR_RESET_HOST_IOWAIT_TIMEOUT	5
 #define MPI3MR_DEFAULT_SHUTDOWN_TIME		120
 
 #define MPI3MR_WATCHDOG_INTERVAL		1000 /* in milli seconds */
@@ -632,10 +633,14 @@  struct scmd_priv {
  * @dev_handle_bitmap_sz: Device handle bitmap size
  * @removepend_bitmap: Remove pending bitmap
  * @delayed_rmhs_list: Delayed device removal list
+ * @fault_dbg: Fault debug flag
  * @reset_in_progress: Reset in progress flag
  * @unrecoverable: Controller unrecoverable flag
+ * @reset_mutex: Controller reset mutex
+ * @reset_waitq: Controller reset  wait queue
  * @diagsave_timeout: Diagnostic information save timeout
  * @logging_level: Controller debug logging level
+ * @flush_io_count: I/O count to flush after reset
  * @current_event: Firmware event currently in process
  * @driver_info: Driver, Kernel, OS information to firmware
  * @change_count: Topology change count
@@ -750,11 +755,15 @@  struct mpi3mr_ioc {
 	void *removepend_bitmap;
 	struct list_head delayed_rmhs_list;
 
+	u8 fault_dbg;
 	u8 reset_in_progress;
 	u8 unrecoverable;
+	struct mutex reset_mutex;
+	wait_queue_head_t reset_waitq;
 
 	u16 diagsave_timeout;
 	int logging_level;
+	u16 flush_io_count;
 
 	struct mpi3mr_fwevt *current_event;
 	Mpi3DriverInfoLayout_t driver_info;
@@ -803,8 +812,8 @@  struct delayed_dev_rmhs_node {
 
 int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc);
 void mpi3mr_cleanup_resources(struct mpi3mr_ioc *mrioc);
-int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc);
-void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc);
+int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc, u8 re_init);
+void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc, u8 re_init);
 int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async);
 int mpi3mr_admin_request_post(struct mpi3mr_ioc *mrioc, void *admin_req,
 u16 admin_req_sz, u8 ignore_reset);
@@ -830,6 +839,8 @@  void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc);
 
 int mpi3mr_soft_reset_handler(struct mpi3mr_ioc *mrioc,
 			      u32 reset_reason, u8 snapdump);
+int mpi3mr_diagfault_reset_handler(struct mpi3mr_ioc *mrioc,
+				   u32 reset_reason);
 void mpi3mr_ioc_disable_intr(struct mpi3mr_ioc *mrioc);
 void mpi3mr_ioc_enable_intr(struct mpi3mr_ioc *mrioc);
 
@@ -837,4 +848,11 @@  enum mpi3mr_iocstate mpi3mr_get_iocstate(struct mpi3mr_ioc *mrioc);
 int mpi3mr_send_event_ack(struct mpi3mr_ioc *mrioc, u8 event,
 			  u32 event_ctx);
 
+void mpi3mr_wait_for_host_io(struct mpi3mr_ioc *mrioc, u32 timeout);
+void mpi3mr_cleanup_fwevt_list(struct mpi3mr_ioc *mrioc);
+void mpi3mr_flush_host_io(struct mpi3mr_ioc *mrioc);
+void mpi3mr_invalidate_devhandles(struct mpi3mr_ioc *mrioc);
+void mpi3mr_rfresh_tgtdevs(struct mpi3mr_ioc *mrioc);
+void mpi3mr_flush_delayed_rmhs_list(struct mpi3mr_ioc *mrioc);
+
 #endif /*MPI3MR_H_INCLUDED*/
diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c b/drivers/scsi/mpi3mr/mpi3mr_fw.c
index de2de39c719e..6129065c34b7 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
@@ -1604,6 +1604,40 @@  void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc)
 	}
 }
 
+/**
+ * mpi3mr_kill_ioc - Kill the controller
+ * @mrioc: Adapter instance reference
+ * @reason: reason for the failure.
+ *
+ * If fault debug is enabled, display the fault info else issue
+ * diag fault and freeze the system for controller debug
+ * purpose.
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_kill_ioc(struct mpi3mr_ioc *mrioc, u32 reason)
+{
+	enum mpi3mr_iocstate ioc_state;
+
+	if (!mrioc->fault_dbg)
+		return;
+
+	dump_stack();
+
+	ioc_state = mpi3mr_get_iocstate(mrioc);
+	if (ioc_state == MRIOC_STATE_FAULT)
+		mpi3mr_print_fault_info(mrioc);
+	else {
+		ioc_err(mrioc, "Firmware is halted due to the reason %d\n",
+		    reason);
+		mpi3mr_diagfault_reset_handler(mrioc, reason);
+	}
+	if (mrioc->fault_dbg == 2)
+		for (;;)
+			;
+	else
+		panic("panic in %s\n", __func__);
+}
 
 /**
  * mpi3mr_setup_admin_qpair - Setup admin queue pair
@@ -2347,6 +2381,7 @@  static int mpi3mr_alloc_chain_bufs(struct mpi3mr_ioc *mrioc)
 	return retval;
 }
 
+
 /**
  * mpi3mr_port_enable_complete - Mark port enable complete
  * @mrioc: Adapter instance reference
@@ -2557,6 +2592,7 @@  int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc)
 /**
  * mpi3mr_init_ioc - Initialize the controller
  * @mrioc: Adapter instance reference
+ * @re_init: Flag to indicate is this fresh init or re-init
  *
  * This the controller initialization routine, executed either
  * after soft reset or from pci probe callback.
@@ -2569,7 +2605,7 @@  int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc)
  *
  * Return: 0 on success and non-zero on failure.
  */
-int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
+int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc, u8 re_init)
 {
 	int retval = 0;
 	enum mpi3mr_iocstate ioc_state;
@@ -2579,12 +2615,14 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 	Mpi3IOCFactsData_t facts_data;
 
 	mrioc->change_count = 0;
-	mrioc->cpu_count = num_online_cpus();
-	retval = mpi3mr_setup_resources(mrioc);
-	if (retval) {
-		ioc_err(mrioc, "Failed to setup resources:error %d\n",
-		    retval);
-		goto out_nocleanup;
+	if (!re_init) {
+		mrioc->cpu_count = num_online_cpus();
+		retval = mpi3mr_setup_resources(mrioc);
+		if (retval) {
+			ioc_err(mrioc, "Failed to setup resources:error %d\n",
+			    retval);
+			goto out_nocleanup;
+		}
 	}
 	ioc_status = readl(&mrioc->sysif_regs->IOCStatus);
 	ioc_config = readl(&mrioc->sysif_regs->IOCConfiguration);
@@ -2660,12 +2698,15 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 		goto out_failed;
 	}
 
-	retval = mpi3mr_setup_isr(mrioc, 1);
-	if (retval) {
-		ioc_err(mrioc, "Failed to setup ISR error %d\n",
-		    retval);
-		goto out_failed;
-	}
+	if (!re_init) {
+		retval = mpi3mr_setup_isr(mrioc, 1);
+		if (retval) {
+			ioc_err(mrioc, "Failed to setup ISR error %d\n",
+			    retval);
+			goto out_failed;
+		}
+	} else
+		mpi3mr_ioc_enable_intr(mrioc);
 
 	retval = mpi3mr_issue_iocfacts(mrioc, &facts_data);
 	if (retval) {
@@ -2675,11 +2716,14 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 	}
 
 	mpi3mr_process_factsdata(mrioc, &facts_data);
-	retval = mpi3mr_check_reset_dma_mask(mrioc);
-	if (retval) {
-		ioc_err(mrioc, "Resetting dma mask failed %d\n",
-		    retval);
-		goto out_failed;
+	if (!re_init) {
+		retval = mpi3mr_check_reset_dma_mask(mrioc);
+		if (retval) {
+			ioc_err(mrioc, "Resetting dma mask failed %d\n",
+			    retval);
+			goto out_failed;
+		}
+
 	}
 
 	retval = mpi3mr_alloc_reply_sense_bufs(mrioc);
@@ -2690,13 +2734,15 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 		goto out_failed;
 	}
 
-	retval = mpi3mr_alloc_chain_bufs(mrioc);
-	if (retval) {
-		ioc_err(mrioc, "Failed to allocated chain buffers %d\n",
-		    retval);
-		goto out_failed;
-	}
+	if (!re_init) {
+		retval = mpi3mr_alloc_chain_bufs(mrioc);
+		if (retval) {
+			ioc_err(mrioc, "Failed to allocated chain buffers %d\n",
+			    retval);
+			goto out_failed;
+		}
 
+	}
 	retval = mpi3mr_issue_iocinit(mrioc);
 	if (retval) {
 		ioc_err(mrioc, "Failed to Issue IOC Init %d\n",
@@ -2711,11 +2757,13 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 	writel(mrioc->sbq_host_index,
 	    &mrioc->sysif_regs->SenseBufferFreeHostIndex);
 
-	retval = mpi3mr_setup_isr(mrioc, 0);
-	if (retval) {
-		ioc_err(mrioc, "Failed to re-setup ISR, error %d\n",
-		    retval);
-		goto out_failed;
+	if (!re_init)  {
+		retval = mpi3mr_setup_isr(mrioc, 0);
+		if (retval) {
+			ioc_err(mrioc, "Failed to re-setup ISR, error %d\n",
+			    retval);
+			goto out_failed;
+		}
 	}
 
 	retval = mpi3mr_create_op_queues(mrioc);
@@ -2725,6 +2773,14 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 		goto out_failed;
 	}
 
+	if (re_init &&
+	    (mrioc->shost->nr_hw_queues > mrioc->num_op_reply_q)) {
+		ioc_err(mrioc,
+		    "Cannot create minimum number of OpQueues expected:%d created:%d\n",
+		    mrioc->shost->nr_hw_queues, mrioc->num_op_reply_q);
+		goto out_failed;
+	}
+
 	for (i = 0; i < MPI3_EVENT_NOTIFY_EVENTMASK_WORDS; i++)
 		mrioc->event_masks[i] = -1;
 
@@ -2748,14 +2804,109 @@  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc)
 		goto out_failed;
 	}
 
+	if (re_init) {
+		ioc_info(mrioc, "Issuing Port Enable\n");
+		retval = mpi3mr_issue_port_enable(mrioc, 0);
+		if (retval) {
+			ioc_err(mrioc, "Failed to issue port enable %d\n",
+			    retval);
+			goto out_failed;
+		}
+	}
 	return retval;
 
 out_failed:
-	mpi3mr_cleanup_ioc(mrioc);
+	mpi3mr_cleanup_ioc(mrioc, re_init);
 out_nocleanup:
 	return retval;
 }
 
+/**
+ * mpi3mr_memset_op_reply_q_buffers - memset the operational reply queue's
+ *					segments
+ * @mrioc: Adapter instance reference
+ * @qidx: Operational reply queue index
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_memset_op_reply_q_buffers(struct mpi3mr_ioc *mrioc, u16 qidx)
+{
+	struct op_reply_qinfo *op_reply_q = mrioc->op_reply_qinfo + qidx;
+	struct segments *segments;
+	int i, size;
+
+	if (!op_reply_q->q_segments)
+		return;
+
+	size = op_reply_q->segment_qd * mrioc->op_reply_desc_sz;
+	segments = op_reply_q->q_segments;
+	for (i = 0; i < op_reply_q->num_segments; i++)
+		memset(segments[i].segment, 0, size);
+}
+
+/**
+ * mpi3mr_memset_op_req_q_buffers - memset the operational request queue's
+ *					segments
+ * @mrioc: Adapter instance reference
+ * @qidx: Operational request queue index
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_memset_op_req_q_buffers(struct mpi3mr_ioc *mrioc, u16 qidx)
+{
+	struct op_req_qinfo *op_req_q = mrioc->req_qinfo + qidx;
+	struct segments *segments;
+	int i, size;
+
+	if (!op_req_q->q_segments)
+		return;
+
+	size = op_req_q->segment_qd * mrioc->facts.op_req_sz;
+	segments = op_req_q->q_segments;
+	for (i = 0; i < op_req_q->num_segments; i++)
+		memset(segments[i].segment, 0, size);
+}
+
+/**
+ * mpi3mr_memset_buffers - memset memory for a controller
+ * @mrioc: Adapter instance reference
+ *
+ * clear all the memory allocated for a controller, typically
+ * called post reset to reuse the memory allocated during the
+ * controller init.
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_memset_buffers(struct mpi3mr_ioc *mrioc)
+{
+	u16 i;
+
+	memset(mrioc->admin_req_base, 0, mrioc->admin_req_q_sz);
+	memset(mrioc->admin_reply_base, 0, mrioc->admin_reply_q_sz);
+
+	memset(mrioc->init_cmds.reply, 0, sizeof(*mrioc->init_cmds.reply));
+	for (i = 0; i < MPI3MR_NUM_DEVRMCMD; i++)
+		memset(mrioc->dev_rmhs_cmds[i].reply, 0,
+		    sizeof(*mrioc->dev_rmhs_cmds[i].reply));
+	memset(mrioc->removepend_bitmap, 0, mrioc->dev_handle_bitmap_sz);
+	memset(mrioc->devrem_bitmap, 0, mrioc->devrem_bitmap_sz);
+
+	for (i = 0; i < mrioc->num_queues; i++) {
+		mrioc->op_reply_qinfo[i].qid = 0;
+		mrioc->op_reply_qinfo[i].ci = 0;
+		mrioc->op_reply_qinfo[i].num_replies = 0;
+		mrioc->op_reply_qinfo[i].ephase = 0;
+		mpi3mr_memset_op_reply_q_buffers(mrioc, i);
+
+		mrioc->req_qinfo[i].ci = 0;
+		mrioc->req_qinfo[i].pi = 0;
+		mrioc->req_qinfo[i].num_requests = 0;
+		mrioc->req_qinfo[i].qid = 0;
+		mrioc->req_qinfo[i].reply_qid = 0;
+		spin_lock_init(&mrioc->req_qinfo[i].q_lock);
+		mpi3mr_memset_op_req_q_buffers(mrioc, i);
+	}
+}
 
 /**
  * mpi3mr_free_mem - Free memory allocated for a controller
@@ -2926,6 +3077,7 @@  static void mpi3mr_issue_ioc_shutdown(struct mpi3mr_ioc *mrioc)
 /**
  * mpi3mr_cleanup_ioc - Cleanup controller
  * @mrioc: Adapter instance reference
+ * @re_init: Cleanup due to a reinit or not
  *
  * Controller cleanup handler, Message unit reset or soft reset
  * and shutdown notification is issued to the controller and the
@@ -2933,11 +3085,12 @@  static void mpi3mr_issue_ioc_shutdown(struct mpi3mr_ioc *mrioc)
  *
  * Return: Nothing.
  */
-void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc)
+void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc, u8 re_init)
 {
 	enum mpi3mr_iocstate ioc_state;
 
-	mpi3mr_stop_watchdog(mrioc);
+	if (!re_init)
+		mpi3mr_stop_watchdog(mrioc);
 
 	mpi3mr_ioc_disable_intr(mrioc);
 
@@ -2951,13 +3104,94 @@  void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc)
 			    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_SOFT_RESET,
 			    MPI3MR_RESET_FROM_MUR_FAILURE);
 
-		 mpi3mr_issue_ioc_shutdown(mrioc);
+		if (!re_init)
+			mpi3mr_issue_ioc_shutdown(mrioc);
 	}
 
-	mpi3mr_free_mem(mrioc);
-	mpi3mr_cleanup_resources(mrioc);
+	if (!re_init) {
+		mpi3mr_free_mem(mrioc);
+		mpi3mr_cleanup_resources(mrioc);
+	}
+}
+
+/**
+ * mpi3mr_drv_cmd_comp_reset - Flush a internal driver command
+ * @mrioc: Adapter instance reference
+ * @cmdptr: Internal command tracker
+ *
+ * Complete an internal driver commands with state indicating it
+ * is completed due to reset.
+ *
+ * Return: Nothing.
+ */
+static inline void mpi3mr_drv_cmd_comp_reset(struct mpi3mr_ioc *mrioc,
+	struct mpi3mr_drv_cmd *cmdptr)
+{
+	if (cmdptr->state & MPI3MR_CMD_PENDING) {
+		cmdptr->state |= MPI3MR_CMD_RESET;
+		cmdptr->state &= ~MPI3MR_CMD_PENDING;
+		if (cmdptr->is_waiting) {
+			complete(&cmdptr->done);
+			cmdptr->is_waiting = 0;
+		} else if (cmdptr->callback)
+			cmdptr->callback(mrioc, cmdptr);
+	}
 }
 
+/**
+ * mpi3mr_flush_drv_cmds - Flush internaldriver commands
+ * @mrioc: Adapter instance reference
+ *
+ * Flush all internal driver commands post reset
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_flush_drv_cmds(struct mpi3mr_ioc *mrioc)
+{
+	struct mpi3mr_drv_cmd *cmdptr;
+	u8 i;
+
+	cmdptr = &mrioc->init_cmds;
+	mpi3mr_drv_cmd_comp_reset(mrioc, cmdptr);
+
+	for (i = 0; i < MPI3MR_NUM_DEVRMCMD; i++) {
+		cmdptr = &mrioc->dev_rmhs_cmds[i];
+		mpi3mr_drv_cmd_comp_reset(mrioc, cmdptr);
+	}
+}
+
+/**
+ * mpi3mr_diagfault_reset_handler - Diag fault reset handler
+ * @mrioc: Adapter instance reference
+ * @reset_reason: Reset reason code
+ *
+ * This is an handler for issuing diag fault reset from the
+ * applications through IOCTL path to stop the execution of the
+ * controller
+ *
+ * Return: 0 on success, non-zero on failure.
+ */
+int mpi3mr_diagfault_reset_handler(struct mpi3mr_ioc *mrioc,
+	u32 reset_reason)
+{
+	int retval = 0;
+
+	mrioc->reset_in_progress = 1;
+
+	mpi3mr_ioc_disable_intr(mrioc);
+
+	retval = mpi3mr_issue_reset(mrioc,
+	    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT, reset_reason);
+
+	if (retval) {
+		ioc_err(mrioc, "The diag fault reset failed: reason %d\n",
+		    reset_reason);
+		mpi3mr_ioc_enable_intr(mrioc);
+	}
+	ioc_info(mrioc, "%s\n", ((retval == 0) ? "SUCCESS" : "FAILED"));
+	mrioc->reset_in_progress = 0;
+	return retval;
+}
 
 /**
  * mpi3mr_soft_reset_handler - Reset the controller
@@ -2965,12 +3199,120 @@  void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc)
  * @reset_reason: Reset reason code
  * @snapdump: Flag to generate snapdump in firmware or not
  *
- * TBD
+ * This is an handler for recovering controller by issuing soft
+ * reset are diag fault reset.  This is a blocking function and
+ * when one reset is executed if any other resets they will be
+ * blocked. All IOCTLs/IO will be blocked during the reset. If
+ * controller reset is successful then the controller will be
+ * reinitalized, otherwise the controller will be marked as not
+ * recoverable
+ *
+ * In snapdump bit is set, the controller is issued with diag
+ * fault reset so that the firmware can create a snap dump and
+ * post that the firmware will result in F000 fault and the
+ * driver will issue soft reset to recover from that.
  *
  * Return: 0 on success, non-zero on failure.
  */
 int mpi3mr_soft_reset_handler(struct mpi3mr_ioc *mrioc,
 	u32 reset_reason, u8 snapdump)
 {
-	return 0;
+	int retval = 0, i;
+	unsigned long flags;
+	u32 host_diagnostic, timeout = MPI3_SYSIF_DIAG_SAVE_TIMEOUT * 10;
+
+	if (mrioc->fault_dbg) {
+		if (snapdump)
+			mpi3mr_set_diagsave(mrioc);
+		mpi3mr_kill_ioc(mrioc, reset_reason);
+	}
+
+	/*
+	 * Block new resets until the currently executing one is finished and
+	 * return the status of the existing reset for all blocked resets
+	 */
+	if (!mutex_trylock(&mrioc->reset_mutex)) {
+		ioc_info(mrioc, "Another reset in progress\n");
+		return -1;
+	}
+	mrioc->reset_in_progress = 1;
+
+	if ((!snapdump) && (reset_reason != MPI3MR_RESET_FROM_FAULT_WATCH) &&
+	    (reset_reason != MPI3MR_RESET_FROM_CIACTIV_FAULT)) {
+
+		for (i = 0; i < MPI3_EVENT_NOTIFY_EVENTMASK_WORDS; i++)
+			mrioc->event_masks[i] = -1;
+
+		retval = mpi3mr_issue_event_notification(mrioc);
+
+		if (retval) {
+			ioc_err(mrioc,
+			    "Failed to turn off events prior to reset %d\n",
+			    retval);
+		}
+	}
+
+	mpi3mr_ioc_disable_intr(mrioc);
+
+	if (snapdump) {
+		mpi3mr_set_diagsave(mrioc);
+		retval = mpi3mr_issue_reset(mrioc,
+		    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT, reset_reason);
+		if (!retval) {
+			do {
+				host_diagnostic =
+				    readl(&mrioc->sysif_regs->HostDiagnostic);
+				if (!(host_diagnostic &
+				    MPI3_SYSIF_HOST_DIAG_SAVE_IN_PROGRESS))
+					break;
+				msleep(100);
+			} while (--timeout);
+		}
+	}
+
+	retval = mpi3mr_issue_reset(mrioc,
+	    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_SOFT_RESET, reset_reason);
+	if (retval) {
+		ioc_err(mrioc, "Failed to issue soft reset to the ioc\n");
+		goto out;
+	}
+
+	mpi3mr_flush_delayed_rmhs_list(mrioc);
+	mpi3mr_flush_drv_cmds(mrioc);
+	memset(mrioc->devrem_bitmap, 0, mrioc->devrem_bitmap_sz);
+	memset(mrioc->removepend_bitmap, 0, mrioc->dev_handle_bitmap_sz);
+	mpi3mr_cleanup_fwevt_list(mrioc);
+	mpi3mr_flush_host_io(mrioc);
+	mpi3mr_invalidate_devhandles(mrioc);
+	mpi3mr_memset_buffers(mrioc);
+	retval = mpi3mr_init_ioc(mrioc, 1);
+	if (retval) {
+		pr_err(IOCNAME "reinit after soft reset failed: reason %d\n",
+		    mrioc->name, reset_reason);
+		goto out;
+	}
+	ssleep(10);
+
+out:
+	if (!retval) {
+		mrioc->reset_in_progress = 0;
+		scsi_unblock_requests(mrioc->shost);
+		mpi3mr_rfresh_tgtdevs(mrioc);
+		spin_lock_irqsave(&mrioc->watchdog_lock, flags);
+		if (mrioc->watchdog_work_q)
+			queue_delayed_work(mrioc->watchdog_work_q,
+			    &mrioc->watchdog_work,
+			    msecs_to_jiffies(MPI3MR_WATCHDOG_INTERVAL));
+		spin_unlock_irqrestore(&mrioc->watchdog_lock, flags);
+	} else {
+		mpi3mr_issue_reset(mrioc,
+		    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT, reset_reason);
+		mrioc->unrecoverable = 1;
+		mrioc->reset_in_progress = 0;
+		retval = -1;
+	}
+
+	mutex_unlock(&mrioc->reset_mutex);
+	ioc_info(mrioc, "%s\n", ((retval == 0) ? "SUCCESS" : "FAILED"));
+	return retval;
 }
diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index 9999d4c9be05..4d94352a4d48 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -311,6 +311,88 @@  void mpi3mr_cleanup_fwevt_list(struct mpi3mr_ioc *mrioc)
 	}
 }
 
+/**
+ * mpi3mr_invalidate_devhandles -Invalidate device handles
+ * @mrioc: Adapter instance reference
+ *
+ * Invalidate the device handles in the target device structures
+ * . Called post reset prior to reinitializing the controller.
+ *
+ * Return: Nothing.
+ */
+void mpi3mr_invalidate_devhandles(struct mpi3mr_ioc *mrioc)
+{
+	struct mpi3mr_tgt_dev *tgtdev;
+	struct mpi3mr_stgt_priv_data *tgt_priv;
+
+	list_for_each_entry(tgtdev, &mrioc->tgtdev_list, list) {
+		tgtdev->dev_handle = MPI3MR_INVALID_DEV_HANDLE;
+		if (tgtdev->starget && tgtdev->starget->hostdata) {
+			tgt_priv = tgtdev->starget->hostdata;
+			tgt_priv->dev_handle = MPI3MR_INVALID_DEV_HANDLE;
+		}
+	}
+}
+
+
+/**
+ * mpi3mr_flush_scmd - Flush individual SCSI command
+ * @rq: Block request
+ * @data: Adapter instance reference
+ *
+ * Return the SCSI command to the upper layers if it is in LLD
+ * scope.
+ *
+ * Return: true always.
+ */
+
+static bool mpi3mr_flush_scmd(struct request *rq,
+	void *data, bool reserved)
+{
+	struct mpi3mr_ioc *mrioc = (struct mpi3mr_ioc *)data;
+	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
+	struct scmd_priv *priv = NULL;
+
+	if (scmd) {
+		priv = scsi_cmd_priv(scmd);
+		if (!priv->in_lld_scope)
+			goto out;
+
+		mpi3mr_clear_scmd_priv(mrioc, scmd);
+		scsi_dma_unmap(scmd);
+		scmd->result = DID_RESET << 16;
+		scsi_print_command(scmd);
+		scmd->scsi_done(scmd);
+		mrioc->flush_io_count++;
+	}
+
+out:
+	return(true);
+}
+
+
+/**
+ * mpi3mr_flush_host_io -  Flush host I/Os
+ * @mrioc: Adapter instance reference
+ *
+ * Flush all of the pending I/Os by calling
+ * blk_mq_tagset_busy_iter() for each possible tag. This is
+ * executed post controller reset
+ *
+ * Return: Nothing.
+ */
+void mpi3mr_flush_host_io(struct mpi3mr_ioc *mrioc)
+{
+	struct Scsi_Host *shost = mrioc->shost;
+
+	mrioc->flush_io_count = 0;
+	ioc_info(mrioc, "%s :Flushing Host I/O cmds post reset\n", __func__);
+	blk_mq_tagset_busy_iter(&shost->tag_set,
+	    mpi3mr_flush_scmd, (void *)mrioc);
+	ioc_info(mrioc, "%s :Flushed %d Host I/O cmds\n", __func__,
+	    mrioc->flush_io_count);
+}
+
 /**
  * mpi3mr_alloc_tgtdev - target device allocator
  *
@@ -2513,11 +2595,14 @@  mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	INIT_LIST_HEAD(&mrioc->tgtdev_list);
 	INIT_LIST_HEAD(&mrioc->delayed_rmhs_list);
 
+	mutex_init(&mrioc->reset_mutex);
 	mpi3mr_init_drv_cmd(&mrioc->init_cmds, MPI3MR_HOSTTAG_INITCMDS);
 
 	if (pdev->revision)
 		mrioc->enable_segqueue = true;
 
+	init_waitqueue_head(&mrioc->reset_waitq);
+
 	mrioc->logging_level = logging_level;
 	mrioc->shost = shost;
 	mrioc->pdev = pdev;
@@ -2542,7 +2627,7 @@  mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	}
 
 	mrioc->is_driver_loading = 1;
-	if (mpi3mr_init_ioc(mrioc)) {
+	if (mpi3mr_init_ioc(mrioc, 0)) {
 		ioc_err(mrioc, "failure at %s:%d/%s()!\n",
 		    __FILE__, __LINE__, __func__);
 		retval = -ENODEV;
@@ -2565,7 +2650,7 @@  mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	return retval;
 
 addhost_failed:
-	mpi3mr_cleanup_ioc(mrioc);
+	mpi3mr_cleanup_ioc(mrioc, 0);
 out_iocinit_failed:
 	destroy_workqueue(mrioc->fwevt_worker_thread);
 out_fwevtthread_failed:
@@ -2615,7 +2700,7 @@  static void mpi3mr_remove(struct pci_dev *pdev)
 		mpi3mr_tgtdev_put(tgtdev);
 	}
 
-	mpi3mr_cleanup_ioc(mrioc);
+	mpi3mr_cleanup_ioc(mrioc, 0);
 
 	spin_lock(&mrioc_list_lock);
 	list_del(&mrioc->list);
@@ -2655,7 +2740,7 @@  static void mpi3mr_shutdown(struct pci_dev *pdev)
 	if (wq)
 		destroy_workqueue(wq);
 
-	mpi3mr_cleanup_ioc(mrioc);
+	mpi3mr_cleanup_ioc(mrioc, 0);
 
 }