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

Pull block driver update from Jens Axboe:
 "Distilled down variant, the rest will pass over to 3.8.  I pulled it
  into the for-linus branch I had waiting for a pull request as well, in
  case you are wondering why there are new entries in here too.  This
  also got rid of two reverts and the ones of the mtip32xx patches that
  went in later in the 3.6 cycle, so the series looks a bit cleaner."

* 'for-linus' of git://git.kernel.dk/linux-block:
  loop: Make explicit loop device destruction lazy
  mtip32xx:Added appropriate timeout value for secure erase
  xen/blkback: Change xen_vbd's flush_support and discard_secure to have type unsigned int, rather than bool
  cciss: select CONFIG_CHECK_SIGNATURE
  cciss: remove unneeded memset()
  xen/blkback: use kmem_cache_zalloc instead of kmem_cache_alloc/memset
  pktcdvd: update MAINTAINERS
  floppy: remove dr, reuse drive on do_floppy_init
  floppy: use common function to check if floppies can be registered
  floppy: properly handle failure on add_disk loop
  floppy: do put_disk on current dr if blk_init_queue fails
  floppy: don't call alloc_ordered_workqueue inside the alloc_disk loop
  xen/blkback: Fix compile warning
  block: Add blk_rq_pos(rq) to sort rq when plushing
  drivers/block: remove CONFIG_EXPERIMENTAL
  block: remove CONFIG_EXPERIMENTAL
  vfs: fix: don't increase bio_slab_max if krealloc() fails
  blkcg: stop iteration early if root_rl is the only request list
  blkcg: Fix use-after-free of q->root_blkg and q->root_rl.blkg

13 files changed, 113 insertions, 68 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 1fa907441f8f..cb7d1a42f2cd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5647,7 +5647,7 @@ S:	Maintained
 F:	drivers/pinctrl/spear/
 
 PKTCDVD DRIVER
-M:	Peter Osterlund <petero2@telia.com>
+M:	Jiri Kosina <jkosina@suse.cz>
 S:	Maintained
 F:	drivers/block/pktcdvd.c
 F:	include/linux/pktcdvd.h
diff --git a/block/Kconfig b/block/Kconfig
index 09acf1b39905..a7e40a7c8214 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -89,7 +89,7 @@ config BLK_DEV_INTEGRITY
 
 config BLK_DEV_THROTTLING
 	bool "Block layer bio throttling support"
-	depends on BLK_CGROUP=y && EXPERIMENTAL
+	depends on BLK_CGROUP=y
 	default n
 	---help---
 	Block layer bio throttling support. It can be used to limit
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index cafcd7431189..d0b770391ad4 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -285,6 +285,13 @@ static void blkg_destroy_all(struct request_queue *q)
 		blkg_destroy(blkg);
 		spin_unlock(&blkcg->lock);
 	}
+
+	/*
+	 * root blkg is destroyed.  Just clear the pointer since
+	 * root_rl does not take reference on root blkg.
+	 */
+	q->root_blkg = NULL;
+	q->root_rl.blkg = NULL;
 }
 
 static void blkg_rcu_free(struct rcu_head *rcu_head)
@@ -326,6 +333,9 @@ struct request_list *__blk_queue_next_rl(struct request_list *rl,
 	 */
 	if (rl == &q->root_rl) {
 		ent = &q->blkg_list;
+		/* There are no more block groups, hence no request lists */
+		if (list_empty(ent))
+			return NULL;
 	} else {
 		blkg = container_of(rl, struct blkcg_gq, rl);
 		ent = &blkg->q_node;
diff --git a/block/blk-core.c b/block/blk-core.c
index a33870b1847b..3c95c4d6e31a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2868,7 +2868,8 @@ static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
 	struct request *rqa = container_of(a, struct request, queuelist);
 	struct request *rqb = container_of(b, struct request, queuelist);
 
-	return !(rqa->q <= rqb->q);
+	return !(rqa->q < rqb->q ||
+		(rqa->q == rqb->q && blk_rq_pos(rqa) < blk_rq_pos(rqb)));
 }
 
 /*
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index f529407db93f..824e09c4d0d7 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -131,6 +131,7 @@ config BLK_CPQ_DA
 config BLK_CPQ_CISS_DA
 	tristate "Compaq Smart Array 5xxx support"
 	depends on PCI
+	select CHECK_SIGNATURE
 	help
 	  This is the driver for Compaq Smart Array 5xxx controllers.
 	  Everyone using these boards should say Y here.
@@ -166,8 +167,8 @@ config BLK_DEV_DAC960
 	  module will be called DAC960.
 
 config BLK_DEV_UMEM
-	tristate "Micro Memory MM5415 Battery Backed RAM support (EXPERIMENTAL)"
-	depends on PCI && EXPERIMENTAL
+	tristate "Micro Memory MM5415 Battery Backed RAM support"
+	depends on PCI
 	---help---
 	  Saying Y here will include support for the MM5415 family of
 	  battery backed (Non-volatile) RAM cards.
@@ -430,8 +431,8 @@ config CDROM_PKTCDVD_BUFFERS
 	  a disc is opened for writing.
 
 config CDROM_PKTCDVD_WCACHE
-	bool "Enable write caching (EXPERIMENTAL)"
-	depends on CDROM_PKTCDVD && EXPERIMENTAL
+	bool "Enable write caching"
+	depends on CDROM_PKTCDVD
 	help
 	  If enabled, write caching will be set for the CD-R/W device. For now
 	  this option is dangerous unless the CD-RW media is known good, as we
@@ -508,8 +509,8 @@ config XEN_BLKDEV_BACKEND
 
 
 config VIRTIO_BLK
-	tristate "Virtio block driver (EXPERIMENTAL)"
-	depends on EXPERIMENTAL && VIRTIO
+	tristate "Virtio block driver"
+	depends on VIRTIO
 	---help---
 	  This is the virtual block driver for virtio.  It can be used with
           lguest or QEMU based VMMs (like KVM or Xen).  Say Y or M.
@@ -528,7 +529,7 @@ config BLK_DEV_HD
 
 config BLK_DEV_RBD
 	tristate "Rados block device (RBD)"
-	depends on INET && EXPERIMENTAL && BLOCK
+	depends on INET && BLOCK
 	select CEPH_LIB
 	select LIBCRC32C
 	select CRYPTO_AES
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index b0f553b26d0f..ca83f96756ad 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -5205,7 +5205,6 @@ static void cciss_shutdown(struct pci_dev *pdev)
 		return;
 	}
 	/* write all data in the battery backed cache to disk */
-	memset(flush_buf, 0, 4);
 	return_code = sendcmd_withirq(h, CCISS_CACHE_FLUSH, flush_buf,
 		4, 0, CTLR_LUNID, TYPE_CMD);
 	kfree(flush_buf);
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 17c675c52295..1c49d7173966 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4109,12 +4109,19 @@ static struct platform_driver floppy_driver = {
 
 static struct platform_device floppy_device[N_DRIVE];
 
+static bool floppy_available(int drive)
+{
+	if (!(allowed_drive_mask & (1 << drive)))
+		return false;
+	if (fdc_state[FDC(drive)].version == FDC_NONE)
+		return false;
+	return true;
+}
+
 static struct kobject *floppy_find(dev_t dev, int *part, void *data)
 {
 	int drive = (*part & 3) | ((*part & 0x80) >> 5);
-	if (drive >= N_DRIVE ||
-	    !(allowed_drive_mask & (1 << drive)) ||
-	    fdc_state[FDC(drive)].version == FDC_NONE)
+	if (drive >= N_DRIVE || !floppy_available(drive))
 		return NULL;
 	if (((*part >> 2) & 0x1f) >= ARRAY_SIZE(floppy_type))
 		return NULL;
@@ -4124,8 +4131,7 @@ static struct kobject *floppy_find(dev_t dev, int *part, void *data)
 
 static int __init do_floppy_init(void)
 {
-	int i, unit, drive;
-	int err, dr;
+	int i, unit, drive, err;
 
 	set_debugt();
 	interruptjiffies = resultjiffies = jiffies;
@@ -4137,34 +4143,32 @@ static int __init do_floppy_init(void)
 
 	raw_cmd = NULL;
 
-	for (dr = 0; dr < N_DRIVE; dr++) {
-		disks[dr] = alloc_disk(1);
-		if (!disks[dr]) {
-			err = -ENOMEM;
-			goto out_put_disk;
-		}
+	floppy_wq = alloc_ordered_workqueue("floppy", 0);
+	if (!floppy_wq)
+		return -ENOMEM;
 
-		floppy_wq = alloc_ordered_workqueue("floppy", 0);
-		if (!floppy_wq) {
+	for (drive = 0; drive < N_DRIVE; drive++) {
+		disks[drive] = alloc_disk(1);
+		if (!disks[drive]) {
 			err = -ENOMEM;
 			goto out_put_disk;
 		}
 
-		disks[dr]->queue = blk_init_queue(do_fd_request, &floppy_lock);
-		if (!disks[dr]->queue) {
+		disks[drive]->queue = blk_init_queue(do_fd_request, &floppy_lock);
+		if (!disks[drive]->queue) {
 			err = -ENOMEM;
-			goto out_destroy_workq;
+			goto out_put_disk;
 		}
 
-		blk_queue_max_hw_sectors(disks[dr]->queue, 64);
-		disks[dr]->major = FLOPPY_MAJOR;
-		disks[dr]->first_minor = TOMINOR(dr);
-		disks[dr]->fops = &floppy_fops;
-		sprintf(disks[dr]->disk_name, "fd%d", dr);
+		blk_queue_max_hw_sectors(disks[drive]->queue, 64);
+		disks[drive]->major = FLOPPY_MAJOR;
+		disks[drive]->first_minor = TOMINOR(drive);
+		disks[drive]->fops = &floppy_fops;
+		sprintf(disks[drive]->disk_name, "fd%d", drive);
 
-		init_timer(&motor_off_timer[dr]);
-		motor_off_timer[dr].data = dr;
-		motor_off_timer[dr].function = motor_off_callback;
+		init_timer(&motor_off_timer[drive]);
+		motor_off_timer[drive].data = drive;
+		motor_off_timer[drive].function = motor_off_callback;
 	}
 
 	err = register_blkdev(FLOPPY_MAJOR, "fd");
@@ -4282,9 +4286,7 @@ static int __init do_floppy_init(void)
 	}
 
 	for (drive = 0; drive < N_DRIVE; drive++) {
-		if (!(allowed_drive_mask & (1 << drive)))
-			continue;
-		if (fdc_state[FDC(drive)].version == FDC_NONE)
+		if (!floppy_available(drive))
 			continue;
 
 		floppy_device[drive].name = floppy_device_name;
@@ -4293,7 +4295,7 @@ static int __init do_floppy_init(void)
 
 		err = platform_device_register(&floppy_device[drive]);
 		if (err)
-			goto out_release_dma;
+			goto out_remove_drives;
 
 		err = device_create_file(&floppy_device[drive].dev,
 					 &dev_attr_cmos);
@@ -4311,29 +4313,34 @@ static int __init do_floppy_init(void)
 
 out_unreg_platform_dev:
 	platform_device_unregister(&floppy_device[drive]);
+out_remove_drives:
+	while (drive--) {
+		if (floppy_available(drive)) {
+			del_gendisk(disks[drive]);
+			device_remove_file(&floppy_device[drive].dev, &dev_attr_cmos);
+			platform_device_unregister(&floppy_device[drive]);
+		}
+	}
 out_release_dma:
 	if (atomic_read(&usage_count))
 		floppy_release_irq_and_dma();
 out_unreg_region:
 	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
 	platform_driver_unregister(&floppy_driver);
-out_destroy_workq:
-	destroy_workqueue(floppy_wq);
 out_unreg_blkdev:
 	unregister_blkdev(FLOPPY_MAJOR, "fd");
 out_put_disk:
-	while (dr--) {
-		del_timer_sync(&motor_off_timer[dr]);
-		if (disks[dr]->queue) {
-			blk_cleanup_queue(disks[dr]->queue);
-			/*
-			 * put_disk() is not paired with add_disk() and
-			 * will put queue reference one extra time. fix it.
-			 */
-			disks[dr]->queue = NULL;
+	for (drive = 0; drive < N_DRIVE; drive++) {
+		if (!disks[drive])
+			break;
+		if (disks[drive]->queue) {
+			del_timer_sync(&motor_off_timer[drive]);
+			blk_cleanup_queue(disks[drive]->queue);
+			disks[drive]->queue = NULL;
 		}
-		put_disk(disks[dr]);
+		put_disk(disks[drive]);
 	}
+	destroy_workqueue(floppy_wq);
 	return err;
 }
 
@@ -4551,8 +4558,7 @@ static void __exit floppy_module_exit(void)
 	for (drive = 0; drive < N_DRIVE; drive++) {
 		del_timer_sync(&motor_off_timer[drive]);
 
-		if ((allowed_drive_mask & (1 << drive)) &&
-		    fdc_state[FDC(drive)].version != FDC_NONE) {
+		if (floppy_available(drive)) {
 			del_gendisk(disks[drive]);
 			device_remove_file(&floppy_device[drive].dev, &dev_attr_cmos);
 			platform_device_unregister(&floppy_device[drive]);
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index e9d594fd12cb..54046e51160a 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -976,8 +976,21 @@ static int loop_clr_fd(struct loop_device *lo)
 	if (lo->lo_state != Lo_bound)
 		return -ENXIO;
 
-	if (lo->lo_refcnt > 1)	/* we needed one fd for the ioctl */
-		return -EBUSY;
+	/*
+	 * If we've explicitly asked to tear down the loop device,
+	 * and it has an elevated reference count, set it for auto-teardown when
+	 * the last reference goes away. This stops $!~#$@ udev from
+	 * preventing teardown because it decided that it needs to run blkid on
+	 * the loopback device whenever they appear. xfstests is notorious for
+	 * failing tests because blkid via udev races with a losetup
+	 * <dev>/do something like mkfs/losetup -d <dev> causing the losetup -d
+	 * command to fail with EBUSY.
+	 */
+	if (lo->lo_refcnt > 1) {
+		lo->lo_flags |= LO_FLAGS_AUTOCLEAR;
+		mutex_unlock(&lo->lo_ctl_mutex);
+		return 0;
+	}
 
 	if (filp == NULL)
 		return -EINVAL;
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index f946d31d6917..adc6f36564cf 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -2035,8 +2035,9 @@ static unsigned int implicit_sector(unsigned char command,
 	}
 	return rv;
 }
-
-static void mtip_set_timeout(struct host_to_dev_fis *fis, unsigned int *timeout)
+static void mtip_set_timeout(struct driver_data *dd,
+					struct host_to_dev_fis *fis,
+					unsigned int *timeout, u8 erasemode)
 {
 	switch (fis->command) {
 	case ATA_CMD_DOWNLOAD_MICRO:
@@ -2044,7 +2045,10 @@ static void mtip_set_timeout(struct host_to_dev_fis *fis, unsigned int *timeout)
 		break;
 	case ATA_CMD_SEC_ERASE_UNIT:
 	case 0xFC:
-		*timeout = 240000; /* 4 minutes */
+		if (erasemode)
+			*timeout = ((*(dd->port->identify + 90) * 2) * 60000);
+		else
+			*timeout = ((*(dd->port->identify + 89) * 2) * 60000);
 		break;
 	case ATA_CMD_STANDBYNOW1:
 		*timeout = 120000;  /* 2 minutes */
@@ -2087,6 +2091,7 @@ static int exec_drive_taskfile(struct driver_data *dd,
 	unsigned int transfer_size;
 	unsigned long task_file_data;
 	int intotal = outtotal + req_task->out_size;
+	int erasemode = 0;
 
 	taskout = req_task->out_size;
 	taskin = req_task->in_size;
@@ -2212,7 +2217,13 @@ static int exec_drive_taskfile(struct driver_data *dd,
 		fis.lba_hi,
 		fis.device);
 
-	mtip_set_timeout(&fis, &timeout);
+	/* check for erase mode support during secure erase.*/
+	if ((fis.command == ATA_CMD_SEC_ERASE_UNIT)
+					&& (outbuf[0] & MTIP_SEC_ERASE_MODE)) {
+		erasemode = 1;
+	}
+
+	mtip_set_timeout(dd, &fis, &timeout, erasemode);
 
 	/* Determine the correct transfer size.*/
 	if (force_single_sector)
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 18627a1d04c5..5f4a917bd8bb 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -33,6 +33,9 @@
 /* offset of Device Control register in PCIe extended capabilites space */
 #define PCIE_CONFIG_EXT_DEVICE_CONTROL_OFFSET	0x48
 
+/* check for erase mode support during secure erase */
+#define MTIP_SEC_ERASE_MODE     0x3
+
 /* # of times to retry timed out/failed IOs */
 #define MTIP_MAX_RETRIES	2
 
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index 9ad3b5ec1dc1..9a54623e52d7 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -158,8 +158,8 @@ struct xen_vbd {
 	struct block_device	*bdev;
 	/* Cached size parameter. */
 	sector_t		size;
-	bool			flush_support;
-	bool			discard_secure;
+	unsigned int		flush_support:1;
+	unsigned int		discard_secure:1;
 };
 
 struct backend_info;
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 4f66171c6683..f58434c2617c 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -105,11 +105,10 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
 {
 	struct xen_blkif *blkif;
 
-	blkif = kmem_cache_alloc(xen_blkif_cachep, GFP_KERNEL);
+	blkif = kmem_cache_zalloc(xen_blkif_cachep, GFP_KERNEL);
 	if (!blkif)
 		return ERR_PTR(-ENOMEM);
 
-	memset(blkif, 0, sizeof(*blkif));
 	blkif->domid = domid;
 	spin_lock_init(&blkif->blk_ring_lock);
 	atomic_set(&blkif->refcnt, 1);
@@ -196,7 +195,7 @@ static void xen_blkif_disconnect(struct xen_blkif *blkif)
 	}
 }
 
-void xen_blkif_free(struct xen_blkif *blkif)
+static void xen_blkif_free(struct xen_blkif *blkif)
 {
 	if (!atomic_dec_and_test(&blkif->refcnt))
 		BUG();
@@ -257,7 +256,7 @@ static struct attribute_group xen_vbdstat_group = {
 VBD_SHOW(physical_device, "%x:%x\n", be->major, be->minor);
 VBD_SHOW(mode, "%s\n", be->mode);
 
-int xenvbd_sysfs_addif(struct xenbus_device *dev)
+static int xenvbd_sysfs_addif(struct xenbus_device *dev)
 {
 	int error;
 
@@ -281,7 +280,7 @@ fail1:	device_remove_file(&dev->dev, &dev_attr_physical_device);
 	return error;
 }
 
-void xenvbd_sysfs_delif(struct xenbus_device *dev)
+static void xenvbd_sysfs_delif(struct xenbus_device *dev)
 {
 	sysfs_remove_group(&dev->dev.kobj, &xen_vbdstat_group);
 	device_remove_file(&dev->dev, &dev_attr_mode);
diff --git a/fs/bio.c b/fs/bio.c
index 9298c65ad9c7..b96fc6ce4855 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -75,6 +75,7 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
 	unsigned int sz = sizeof(struct bio) + extra_size;
 	struct kmem_cache *slab = NULL;
 	struct bio_slab *bslab, *new_bio_slabs;
+	unsigned int new_bio_slab_max;
 	unsigned int i, entry = -1;
 
 	mutex_lock(&bio_slab_lock);
@@ -97,12 +98,13 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
 		goto out_unlock;
 
 	if (bio_slab_nr == bio_slab_max && entry == -1) {
-		bio_slab_max <<= 1;
+		new_bio_slab_max = bio_slab_max << 1;
 		new_bio_slabs = krealloc(bio_slabs,
-					 bio_slab_max * sizeof(struct bio_slab),
+					 new_bio_slab_max * sizeof(struct bio_slab),
 					 GFP_KERNEL);
 		if (!new_bio_slabs)
 			goto out_unlock;
+		bio_slab_max = new_bio_slab_max;
 		bio_slabs = new_bio_slabs;
 	}
 	if (entry == -1)