mtip32xx: do rebuild monitoring asynchronously

Earlier, rebuild monitoring was done in the context of probe. Now the service
thread takes the responsibility of rebuild monitoring, and probe returns good
status.

Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

2 files changed, 65 insertions, 40 deletions

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 9bc10e31a143..b74eab70c3d0 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -87,6 +87,8 @@ static int mtip_major;
 static DEFINE_SPINLOCK(rssd_index_lock);
 static DEFINE_IDA(rssd_index_ida);
 
+static int mtip_block_initialize(struct driver_data *dd);
+
 #ifdef CONFIG_COMPAT
 struct mtip_compat_ide_task_request_s {
         __u8            io_ports[8];
@@ -1031,7 +1033,8 @@ static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout)
 
         to = jiffies + msecs_to_jiffies(timeout);
         do {
-                if (test_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags)) {
+                if (test_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags) &&
+                        test_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags)) {
                         msleep(20);
                         continue; /* svc thd is actively issuing commands */
                 }
@@ -2410,6 +2413,7 @@ static int mtip_ftl_rebuild_poll(struct driver_data *dd)
                                 "FTL rebuild complete (%d secs).\n",
                         jiffies_to_msecs(jiffies - start) / 1000);
                         dd->ftlrebuildflag = 0;
+                        mtip_block_initialize(dd);
                         break;
                 }
                 ssleep(10);
@@ -2454,8 +2458,8 @@ static int mtip_service_thread(void *data)
                 if (kthread_should_stop())
                         break;
 
+                set_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
                 if (test_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags)) {
-                        set_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
                         slot = 1;
                         /* used to restrict the loop to one iteration */
                         slot_start = num_cmd_slots;
@@ -2488,8 +2492,14 @@ static int mtip_service_thread(void *data)
                         }
 
                         clear_bit(MTIP_FLAG_ISSUE_CMDS_BIT, &port->flags);
-                        clear_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
+                } else if (test_bit(MTIP_FLAG_REBUILD_BIT, &port->flags)) {
+                        mtip_ftl_rebuild_poll(dd);
+                        clear_bit(MTIP_FLAG_REBUILD_BIT, &port->flags);
                 }
+                clear_bit(MTIP_FLAG_SVC_THD_ACTIVE_BIT, &port->flags);
+
+                if (test_bit(MTIP_FLAG_SVC_THD_SHOULD_STOP_BIT, &port->flags))
+                        break;
         }
         return 0;
 }
@@ -2658,12 +2668,13 @@ static int mtip_hw_init(struct driver_data *dd)
                 rv = -EFAULT;
                 goto out3;
         }
-        mtip_dump_identify(dd->port);
 
         if (*(dd->port->identify + MTIP_FTL_REBUILD_OFFSET) ==
                 MTIP_FTL_REBUILD_MAGIC) {
-                return mtip_ftl_rebuild_poll(dd);
+                set_bit(MTIP_FLAG_REBUILD_BIT, &dd->port->flags);
+                return MTIP_FTL_REBUILD_MAGIC;
         }
+        mtip_dump_identify(dd->port);
         return rv;
 
 out3:
@@ -3095,40 +3106,24 @@ static void mtip_make_request(struct request_queue *queue, struct bio *bio)
  */
 static int mtip_block_initialize(struct driver_data *dd)
 {
-        int rv = 0;
+        int rv = 0, wait_for_rebuild = 0;
         sector_t capacity;
         unsigned int index = 0;
         struct kobject *kobj;
         unsigned char thd_name[16];
 
+        if (dd->disk)
+                goto skip_create_disk; /* hw init done, before rebuild */
+
         /* Initialize the protocol layer. */
-        rv = mtip_hw_init(dd);
-        if (rv < 0) {
+        wait_for_rebuild = mtip_hw_init(dd);
+        if (wait_for_rebuild < 0) {
                 dev_err(&dd->pdev->dev,
                         "Protocol layer initialization failed\n");
                 rv = -EINVAL;
                 goto protocol_init_error;
         }
 
-        /* Allocate the request queue. */
-        dd->queue = blk_alloc_queue(GFP_KERNEL);
-        if (dd->queue == NULL) {
-                dev_err(&dd->pdev->dev,
-                        "Unable to allocate request queue\n");
-                rv = -ENOMEM;
-                goto block_queue_alloc_init_error;
-        }
-
-        /* Attach our request function to the request queue. */
-        blk_queue_make_request(dd->queue, mtip_make_request);
-
-        /* Set device limits. */
-        set_bit(QUEUE_FLAG_NONROT, &dd->queue->queue_flags);
-        blk_queue_max_segments(dd->queue, MTIP_MAX_SG);
-        blk_queue_physical_block_size(dd->queue, 4096);
-        blk_queue_io_min(dd->queue, 4096);
-        blk_queue_flush(dd->queue, 0);
-
         dd->disk = alloc_disk(MTIP_MAX_MINORS);
         if (dd->disk  == NULL) {
                 dev_err(&dd->pdev->dev,
@@ -3161,11 +3156,39 @@ static int mtip_block_initialize(struct driver_data *dd)
         dd->disk->major         = dd->major;
         dd->disk->first_minor   = dd->instance * MTIP_MAX_MINORS;
         dd->disk->fops          = &mtip_block_ops;
-        dd->disk->queue         = dd->queue;
         dd->disk->private_data  = dd;
-        dd->queue->queuedata    = dd;
         dd->index               = index;
 
+        /*
+         * if rebuild pending, start the service thread, and delay the block
+         * queue creation and add_disk()
+         */
+        if (wait_for_rebuild == MTIP_FTL_REBUILD_MAGIC)
+                goto start_service_thread;
+
+skip_create_disk:
+        /* Allocate the request queue. */
+        dd->queue = blk_alloc_queue(GFP_KERNEL);
+        if (dd->queue == NULL) {
+                dev_err(&dd->pdev->dev,
+                        "Unable to allocate request queue\n");
+                rv = -ENOMEM;
+                goto block_queue_alloc_init_error;
+        }
+
+        /* Attach our request function to the request queue. */
+        blk_queue_make_request(dd->queue, mtip_make_request);
+
+        dd->disk->queue         = dd->queue;
+        dd->queue->queuedata    = dd;
+
+        /* Set device limits. */
+        set_bit(QUEUE_FLAG_NONROT, &dd->queue->queue_flags);
+        blk_queue_max_segments(dd->queue, MTIP_MAX_SG);
+        blk_queue_physical_block_size(dd->queue, 4096);
+        blk_queue_io_min(dd->queue, 4096);
+        blk_queue_flush(dd->queue, 0);
+
         /* Set the capacity of the device in 512 byte sectors. */
         if (!(mtip_hw_get_capacity(dd, &capacity))) {
                 dev_warn(&dd->pdev->dev,
@@ -3188,6 +3211,10 @@ static int mtip_block_initialize(struct driver_data *dd)
                 kobject_put(kobj);
         }
 
+        if (dd->mtip_svc_handler)
+                return rv; /* service thread created for handling rebuild */
+
+start_service_thread:
         sprintf(thd_name, "mtip_svc_thd_%02d", index);
 
         dd->mtip_svc_handler = kthread_run(mtip_service_thread,
@@ -3197,18 +3224,19 @@ static int mtip_block_initialize(struct driver_data *dd)
                 printk(KERN_ERR "mtip32xx: service thread failed to start\n");
                 dd->mtip_svc_handler = NULL;
                 rv = -EFAULT;
-                goto read_capacity_error;
+                goto kthread_run_error;
         }
 
         return rv;
 
-read_capacity_error:
-        /*
-         * Delete our gendisk structure. This also removes the device
-         * from /dev
-         */
+kthread_run_error:
+        /* Delete our gendisk. This also removes the device from /dev */
         del_gendisk(dd->disk);
 
+read_capacity_error:
+        blk_cleanup_queue(dd->queue);
+
+block_queue_alloc_init_error:
 disk_index_error:
         spin_lock(&rssd_index_lock);
         ida_remove(&rssd_index_ida, index);
@@ -3218,11 +3246,7 @@ ida_get_error:
         put_disk(dd->disk);
 
 alloc_disk_error:
-        blk_cleanup_queue(dd->queue);
-
-block_queue_alloc_init_error:
-        /* De-initialize the protocol layer. */
-        mtip_hw_exit(dd);
+        mtip_hw_exit(dd); /* De-initialize the protocol layer. */
 
 protocol_init_error:
         return rv;
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 933192abe178..723d7c4946dc 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -121,6 +121,7 @@
 #define MTIP_FLAG_EH_ACTIVE_BIT                 1
 #define MTIP_FLAG_SVC_THD_ACTIVE_BIT            2
 #define MTIP_FLAG_ISSUE_CMDS_BIT                4
+#define MTIP_FLAG_REBUILD_BIT                   5
 #define MTIP_FLAG_SVC_THD_SHOULD_STOP_BIT       8
 
 /* Register Frame Information Structure (FIS), host to device. */