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 */