Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "It might look big in volume, but when categorized, not a lot of
  drivers are touched.  The pull request contains:

   - mtip32xx fixes from Micron.

   - A slew of drbd updates, this time in a nicer series.

   - bcache, a flash/ssd caching framework from Kent.

   - Fixes for cciss"

* 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits)
  bcache: Use bd_link_disk_holder()
  bcache: Allocator cleanup/fixes
  cciss: bug fix to prevent cciss from loading in kdump crash kernel
  cciss: add cciss_allow_hpsa module parameter
  drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions
  mtip32xx: Workaround for unaligned writes
  bcache: Make sure blocksize isn't smaller than device blocksize
  bcache: Fix merge_bvec_fn usage for when it modifies the bvm
  bcache: Correctly check against BIO_MAX_PAGES
  bcache: Hack around stuff that clones up to bi_max_vecs
  bcache: Set ra_pages based on backing device's ra_pages
  bcache: Take data offset from the bdev superblock.
  mtip32xx: mtip32xx: Disable TRIM support
  mtip32xx: fix a smatch warning
  bcache: Disable broken btree fuzz tester
  bcache: Fix a format string overflow
  bcache: Fix a minor memory leak on device teardown
  bcache: Documentation updates
  bcache: Use WARN_ONCE() instead of __WARN()
  bcache: Add missing #include <linux/prefetch.h>
  ...

2 files changed, 68 insertions, 22 deletions

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 32c678028e53..847107ef0cce 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -728,7 +728,10 @@ static void mtip_async_complete(struct mtip_port *port,
 	atomic_set(&port->commands[tag].active, 0);
 	release_slot(port, tag);
 
-	up(&port->cmd_slot);
+	if (unlikely(command->unaligned))
+		up(&port->cmd_slot_unal);
+	else
+		up(&port->cmd_slot);
 }
 
 /*
@@ -1560,10 +1563,12 @@ static int mtip_get_identify(struct mtip_port *port, void __user *user_buffer)
 	}
 #endif
 
+#ifdef MTIP_TRIM /* Disabling TRIM support temporarily */
 	/* Demux ID.DRAT & ID.RZAT to determine trim support */
 	if (port->identify[69] & (1 << 14) && port->identify[69] & (1 << 5))
 		port->dd->trim_supp = true;
 	else
+#endif
 		port->dd->trim_supp = false;
 
 	/* Set the identify buffer as valid. */
@@ -2557,7 +2562,7 @@ static int mtip_hw_ioctl(struct driver_data *dd, unsigned int cmd,
  */
 static void mtip_hw_submit_io(struct driver_data *dd, sector_t sector,
 			      int nsect, int nents, int tag, void *callback,
-			      void *data, int dir)
+			      void *data, int dir, int unaligned)
 {
 	struct host_to_dev_fis	*fis;
 	struct mtip_port *port = dd->port;
@@ -2570,6 +2575,7 @@ static void mtip_hw_submit_io(struct driver_data *dd, sector_t sector,
 
 	command->scatter_ents = nents;
 
+	command->unaligned = unaligned;
 	/*
 	 * The number of retries for this command before it is
 	 * reported as a failure to the upper layers.
@@ -2598,6 +2604,9 @@ static void mtip_hw_submit_io(struct driver_data *dd, sector_t sector,
 	fis->res3        = 0;
 	fill_command_sg(dd, command, nents);
 
+	if (unaligned)
+		fis->device |= 1 << 7;
+
 	/* Populate the command header */
 	command->command_header->opts =
 			__force_bit2int cpu_to_le32(
@@ -2644,9 +2653,13 @@ static void mtip_hw_submit_io(struct driver_data *dd, sector_t sector,
  * return value
  *      None
  */
-static void mtip_hw_release_scatterlist(struct driver_data *dd, int tag)
+static void mtip_hw_release_scatterlist(struct driver_data *dd, int tag,
+								int unaligned)
 {
+	struct semaphore *sem = unaligned ? &dd->port->cmd_slot_unal :
+							&dd->port->cmd_slot;
 	release_slot(dd->port, tag);
+	up(sem);
 }
 
 /*
@@ -2661,22 +2674,25 @@ static void mtip_hw_release_scatterlist(struct driver_data *dd, int tag)
  *	or NULL if no command slots are available.
  */
 static struct scatterlist *mtip_hw_get_scatterlist(struct driver_data *dd,
-						   int *tag)
+						   int *tag, int unaligned)
 {
+	struct semaphore *sem = unaligned ? &dd->port->cmd_slot_unal :
+							&dd->port->cmd_slot;
+
 	/*
 	 * It is possible that, even with this semaphore, a thread
 	 * may think that no command slots are available. Therefore, we
 	 * need to make an attempt to get_slot().
 	 */
-	down(&dd->port->cmd_slot);
+	down(sem);
 	*tag = get_slot(dd->port);
 
 	if (unlikely(test_bit(MTIP_DDF_REMOVE_PENDING_BIT, &dd->dd_flag))) {
-		up(&dd->port->cmd_slot);
+		up(sem);
 		return NULL;
 	}
 	if (unlikely(*tag < 0)) {
-		up(&dd->port->cmd_slot);
+		up(sem);
 		return NULL;
 	}
 
@@ -3010,6 +3026,11 @@ static inline void hba_setup(struct driver_data *dd)
 		dd->mmio + HOST_HSORG);
 }
 
+static int mtip_device_unaligned_constrained(struct driver_data *dd)
+{
+	return (dd->pdev->device == P420M_DEVICE_ID ? 1 : 0);
+}
+
 /*
  * Detect the details of the product, and store anything needed
  * into the driver data structure.  This includes product type and
@@ -3232,8 +3253,15 @@ static int mtip_hw_init(struct driver_data *dd)
 	for (i = 0; i < MTIP_MAX_SLOT_GROUPS; i++)
 		dd->work[i].port = dd->port;
 
+	/* Enable unaligned IO constraints for some devices */
+	if (mtip_device_unaligned_constrained(dd))
+		dd->unal_qdepth = MTIP_MAX_UNALIGNED_SLOTS;
+	else
+		dd->unal_qdepth = 0;
+
 	/* Counting semaphore to track command slot usage */
-	sema_init(&dd->port->cmd_slot, num_command_slots - 1);
+	sema_init(&dd->port->cmd_slot, num_command_slots - 1 - dd->unal_qdepth);
+	sema_init(&dd->port->cmd_slot_unal, dd->unal_qdepth);
 
 	/* Spinlock to prevent concurrent issue */
 	for (i = 0; i < MTIP_MAX_SLOT_GROUPS; i++)
@@ -3836,7 +3864,7 @@ static void mtip_make_request(struct request_queue *queue, struct bio *bio)
 	struct scatterlist *sg;
 	struct bio_vec *bvec;
 	int nents = 0;
-	int tag = 0;
+	int tag = 0, unaligned = 0;
 
 	if (unlikely(dd->dd_flag & MTIP_DDF_STOP_IO)) {
 		if (unlikely(test_bit(MTIP_DDF_REMOVE_PENDING_BIT,
@@ -3872,7 +3900,15 @@ static void mtip_make_request(struct request_queue *queue, struct bio *bio)
 		return;
 	}
 
-	sg = mtip_hw_get_scatterlist(dd, &tag);
+	if (bio_data_dir(bio) == WRITE && bio_sectors(bio) <= 64 &&
+							dd->unal_qdepth) {
+		if (bio->bi_sector % 8 != 0) /* Unaligned on 4k boundaries */
+			unaligned = 1;
+		else if (bio_sectors(bio) % 8 != 0) /* Aligned but not 4k/8k */
+			unaligned = 1;
+	}
+
+	sg = mtip_hw_get_scatterlist(dd, &tag, unaligned);
 	if (likely(sg != NULL)) {
 		blk_queue_bounce(queue, &bio);
 
@@ -3880,7 +3916,7 @@ static void mtip_make_request(struct request_queue *queue, struct bio *bio)
 			dev_warn(&dd->pdev->dev,
 				"Maximum number of SGL entries exceeded\n");
 			bio_io_error(bio);
-			mtip_hw_release_scatterlist(dd, tag);
+			mtip_hw_release_scatterlist(dd, tag, unaligned);
 			return;
 		}
 
@@ -3900,7 +3936,8 @@ static void mtip_make_request(struct request_queue *queue, struct bio *bio)
 				tag,
 				bio_endio,
 				bio,
-				bio_data_dir(bio));
+				bio_data_dir(bio),
+				unaligned);
 	} else
 		bio_io_error(bio);
 }
@@ -4156,26 +4193,24 @@ static int mtip_block_remove(struct driver_data *dd)
  */
 static int mtip_block_shutdown(struct driver_data *dd)
 {
-	dev_info(&dd->pdev->dev,
-		"Shutting down %s ...\n", dd->disk->disk_name);
-
 	/* Delete our gendisk structure, and cleanup the blk queue. */
 	if (dd->disk) {
-		if (dd->disk->queue)
+		dev_info(&dd->pdev->dev,
+			"Shutting down %s ...\n", dd->disk->disk_name);
+
+		if (dd->disk->queue) {
 			del_gendisk(dd->disk);
-		else
+			blk_cleanup_queue(dd->queue);
+		} else
 			put_disk(dd->disk);
+		dd->disk  = NULL;
+		dd->queue = NULL;
 	}
 
-
 	spin_lock(&rssd_index_lock);
 	ida_remove(&rssd_index_ida, dd->index);
 	spin_unlock(&rssd_index_lock);
 
-	blk_cleanup_queue(dd->queue);
-	dd->disk  = NULL;
-	dd->queue = NULL;
-
 	mtip_hw_shutdown(dd);
 	return 0;
 }
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 8e8334c9dd0f..3bb8a295fbe4 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -52,6 +52,9 @@
 #define MTIP_FTL_REBUILD_MAGIC		0xED51
 #define MTIP_FTL_REBUILD_TIMEOUT_MS	2400000
 
+/* unaligned IO handling */
+#define MTIP_MAX_UNALIGNED_SLOTS	8
+
 /* Macro to extract the tag bit number from a tag value. */
 #define MTIP_TAG_BIT(tag)	(tag & 0x1F)
 
@@ -333,6 +336,8 @@ struct mtip_cmd {
 
 	int scatter_ents; /* Number of scatter list entries used */
 
+	int unaligned; /* command is unaligned on 4k boundary */
+
 	struct scatterlist sg[MTIP_MAX_SG]; /* Scatter list entries */
 
 	int retries; /* The number of retries left for this command. */
@@ -452,6 +457,10 @@ struct mtip_port {
 	 * command slots available.
 	 */
 	struct semaphore cmd_slot;
+
+	/* Semaphore to control queue depth of unaligned IOs */
+	struct semaphore cmd_slot_unal;
+
 	/* Spinlock for working around command-issue bug. */
 	spinlock_t cmd_issue_lock[MTIP_MAX_SLOT_GROUPS];
 };
@@ -502,6 +511,8 @@ struct driver_data {
 
 	int isr_binding;
 
+	int unal_qdepth; /* qdepth of unaligned IO queue */
+
 	struct list_head online_list; /* linkage for online list */
 
 	struct list_head remove_list; /* linkage for removing list */