Merge branch 'for-3.9/drivers' of git://git.kernel.dk/linux-block

Pull block driver bits from Jens Axboe:
 "After the block IO core bits are in, please grab the driver updates
  from below as well.  It contains:

   - Fix ancient regression in dac960.  Nobody must be using that
     anymore...

   - Some good fixes from Guo Ghao for loop, fixing both potential
     oopses and deadlocks.

   - Improve mtip32xx for NUMA systems, by being a bit more clever in
     distributing work.

   - Add IBM RamSan 70/80 driver.  A second round of fixes for that is
     pending, that will come in through for-linus during the 3.9 cycle
     as per usual.

   - A few xen-blk{back,front} fixes from Konrad and Roger.

   - Other minor fixes and improvements."

* 'for-3.9/drivers' of git://git.kernel.dk/linux-block:
  loopdev: ignore negative offset when calculate loop device size
  loopdev: remove an user triggerable oops
  loopdev: move common code into loop_figure_size()
  loopdev: update block device size in loop_set_status()
  loopdev: fix a deadlock
  xen-blkback: use balloon pages for persistent grants
  xen-blkfront: drop the use of llist_for_each_entry_safe
  xen/blkback: Don't trust the handle from the frontend.
  xen-blkback: do not leak mode property
  block: IBM RamSan 70/80 driver fixes
  rsxx: add slab.h include to dma.c
  drivers/block/mtip32xx: add missing GENERIC_HARDIRQS dependency
  block: remove new __devinit/exit annotations on ramsam driver
  block: IBM RamSan 70/80 device driver
  drivers/block/mtip32xx/mtip32xx.c:1726:5: sparse: symbol 'mtip_send_trim' was not declared. Should it be static?
  drivers/block/mtip32xx/mtip32xx.c:4029:1: sparse: symbol 'mtip_workq_sdbf0' was not declared. Should it be static?
  dac960: return success instead of -ENOTTY
  mtip32xx: add trim support
  mtip32xx: Add workqueue and NUMA support
  block: delete super ancient PC-XT driver for 1980's hardware

MAINTAINERS

@@ -6515,6 +6515,12 @@ S:	Maintained
 F:	Documentation/blockdev/ramdisk.txt
 F:	drivers/block/brd.c
 
+RAMSAM DRIVER (IBM RamSan 70/80 PCI SSD Flash Card)
+M:	Joshua Morris <josh.h.morris@us.ibm.com>
+M:	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+S:	Maintained
+F:	drivers/block/rsxx/
+
 RANDOM NUMBER DRIVER
 M:	Theodore Ts'o" <tytso@mit.edu>
 S:	Maintained

drivers/block/DAC960.c

@@ -7054,6 +7054,7 @@ static long DAC960_gam_ioctl(struct file *file, unsigned int Request,
 	else
 		ErrorCode =  0;
       }
+      break;
       default:
 	ErrorCode = -ENOTTY;
     }

drivers/block/Kconfig

@@ -63,19 +63,6 @@ config AMIGA_Z2RAM
 	  To compile this driver as a module, choose M here: the
 	  module will be called z2ram.
 
-config BLK_DEV_XD
-	tristate "XT hard disk support"
-	depends on ISA && ISA_DMA_API
-	select CHECK_SIGNATURE
-	help
-	  Very old 8 bit hard disk controllers used in the IBM XT computer
-	  will be supported if you say Y here.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called xd.
-
-	  It's pretty unlikely that you have one of these: say N.
-
 config GDROM
 	tristate "SEGA Dreamcast GD-ROM drive"
 	depends on SH_DREAMCAST
@@ -544,4 +531,14 @@ config BLK_DEV_RBD
 
 	  If unsure, say N.
 
+config BLK_DEV_RSXX
+	tristate "RamSam PCIe Flash SSD Device Driver"
+	depends on PCI
+	help
+	  Device driver for IBM's high speed PCIe SSD
+	  storage devices: RamSan-70 and RamSan-80.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rsxx.
+
 endif # BLK_DEV

drivers/block/Makefile

@@ -15,7 +15,6 @@ obj-$(CONFIG_ATARI_FLOPPY)	+= ataflop.o
 obj-$(CONFIG_AMIGA_Z2RAM)	+= z2ram.o
 obj-$(CONFIG_BLK_DEV_RAM)	+= brd.o
 obj-$(CONFIG_BLK_DEV_LOOP)	+= loop.o
-obj-$(CONFIG_BLK_DEV_XD)	+= xd.o
 obj-$(CONFIG_BLK_CPQ_DA)	+= cpqarray.o
 obj-$(CONFIG_BLK_CPQ_CISS_DA)  += cciss.o
 obj-$(CONFIG_BLK_DEV_DAC960)	+= DAC960.o
@@ -41,4 +40,6 @@ obj-$(CONFIG_BLK_DEV_DRBD)     += drbd/
 obj-$(CONFIG_BLK_DEV_RBD)     += rbd.o
 obj-$(CONFIG_BLK_DEV_PCIESSD_MTIP32XX)	+= mtip32xx/
 
+obj-$(CONFIG_BLK_DEV_RSXX) += rsxx/
+
 swim_mod-y	:= swim.o swim_asm.o

drivers/block/loop.c

@@ -162,12 +162,13 @@ static struct loop_func_table *xfer_funcs[MAX_LO_CRYPT] = {
 
 static loff_t get_size(loff_t offset, loff_t sizelimit, struct file *file)
 {
-	loff_t size, loopsize;
+	loff_t loopsize;
 
 	/* Compute loopsize in bytes */
-	size = i_size_read(file->f_mapping->host);
-	loopsize = size - offset;
-	/* offset is beyond i_size, wierd but possible */
+	loopsize = i_size_read(file->f_mapping->host);
+	if (offset > 0)
+		loopsize -= offset;
+	/* offset is beyond i_size, weird but possible */
 	if (loopsize < 0)
 		return 0;
 
@@ -190,6 +191,7 @@ figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
 {
 	loff_t size = get_size(offset, sizelimit, lo->lo_backing_file);
 	sector_t x = (sector_t)size;
+	struct block_device *bdev = lo->lo_device;
 
 	if (unlikely((loff_t)x != size))
 		return -EFBIG;
@@ -198,6 +200,9 @@ figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit)
 	if (lo->lo_sizelimit != sizelimit)
 		lo->lo_sizelimit = sizelimit;
 	set_capacity(lo->lo_disk, x);
+	bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9);
+	/* let user-space know about the new size */
+	kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
 	return 0;
 }
 
@@ -1091,10 +1096,10 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 		return err;
 
 	if (lo->lo_offset != info->lo_offset ||
-	    lo->lo_sizelimit != info->lo_sizelimit) {
+	    lo->lo_sizelimit != info->lo_sizelimit)
 		if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit))
 			return -EFBIG;
-	}
+
 	loop_config_discard(lo);
 
 	memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE);
@@ -1271,28 +1276,10 @@ loop_get_status64(struct loop_device *lo, struct loop_info64 __user *arg) {
 
 static int loop_set_capacity(struct loop_device *lo, struct block_device *bdev)
 {
-	int err;
-	sector_t sec;
-	loff_t sz;
-
-	err = -ENXIO;
 	if (unlikely(lo->lo_state != Lo_bound))
-		goto out;
-	err = figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit);
-	if (unlikely(err))
-		goto out;
-	sec = get_capacity(lo->lo_disk);
-	/* the width of sector_t may be narrow for bit-shift */
-	sz = sec;
-	sz <<= 9;
-	mutex_lock(&bdev->bd_mutex);
-	bd_set_size(bdev, sz);
-	/* let user-space know about the new size */
-	kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
-	mutex_unlock(&bdev->bd_mutex);
+		return -ENXIO;
 
- out:
-	return err;
+	return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit);
 }
 
 static int lo_ioctl(struct block_device *bdev, fmode_t mode,
@@ -1845,11 +1832,15 @@ static int __init loop_init(void)
 		max_part = (1UL << part_shift) - 1;
 	}
 
-	if ((1UL << part_shift) > DISK_MAX_PARTS)
-		return -EINVAL;
+	if ((1UL << part_shift) > DISK_MAX_PARTS) {
+		err = -EINVAL;
+		goto misc_out;
+	}
 
-	if (max_loop > 1UL << (MINORBITS - part_shift))
-		return -EINVAL;
+	if (max_loop > 1UL << (MINORBITS - part_shift)) {
+		err = -EINVAL;
+		goto misc_out;
+	}
 
 	/*
 	 * If max_loop is specified, create that many devices upfront.
@@ -1867,8 +1858,10 @@ static int __init loop_init(void)
 		range = 1UL << MINORBITS;
 	}
 
-	if (register_blkdev(LOOP_MAJOR, "loop"))
-		return -EIO;
+	if (register_blkdev(LOOP_MAJOR, "loop")) {
+		err = -EIO;
+		goto misc_out;
+	}
 
 	blk_register_region(MKDEV(LOOP_MAJOR, 0), range,
 				  THIS_MODULE, loop_probe, NULL, NULL);
@@ -1881,6 +1874,10 @@ static int __init loop_init(void)
 
 	printk(KERN_INFO "loop: module loaded\n");
 	return 0;
+
+misc_out:
+	misc_deregister(&loop_misc);
+	return err;
 }
 
 static int loop_exit_cb(int id, void *ptr, void *data)

drivers/block/mtip32xx/Kconfig

@@ -4,6 +4,6 @@
 
 config BLK_DEV_PCIESSD_MTIP32XX
 	tristate "Block Device Driver for Micron PCIe SSDs"
-	depends on PCI
+	depends on PCI && GENERIC_HARDIRQS
 	help
           This enables the block driver for Micron PCIe SSDs.

drivers/block/mtip32xx/mtip32xx.h

@@ -164,6 +164,35 @@ struct smart_attr {
 	u8 res[3];
 } __packed;
 
+struct mtip_work {
+	struct work_struct work;
+	void *port;
+	int cpu_binding;
+	u32 completed;
+} ____cacheline_aligned_in_smp;
+
+#define DEFINE_HANDLER(group)                                  \
+	void mtip_workq_sdbf##group(struct work_struct *work)       \
+	{                                                      \
+		struct mtip_work *w = (struct mtip_work *) work;         \
+		mtip_workq_sdbfx(w->port, group, w->completed);     \
+	}
+
+#define MTIP_TRIM_TIMEOUT_MS		240000
+#define MTIP_MAX_TRIM_ENTRIES		8
+#define MTIP_MAX_TRIM_ENTRY_LEN 	0xfff8
+
+struct mtip_trim_entry {
+	u32 lba;   /* starting lba of region */
+	u16 rsvd;  /* unused */
+	u16 range; /* # of 512b blocks to trim */
+} __packed;
+
+struct mtip_trim {
+	/* Array of regions to trim */
+	struct mtip_trim_entry entry[MTIP_MAX_TRIM_ENTRIES];
+} __packed;
+
 /* Register Frame Information Structure (FIS), host to device. */
 struct host_to_dev_fis {
 	/*
@@ -424,7 +453,7 @@ struct mtip_port {
 	 */
 	struct semaphore cmd_slot;
 	/* Spinlock for working around command-issue bug. */
-	spinlock_t cmd_issue_lock;
+	spinlock_t cmd_issue_lock[MTIP_MAX_SLOT_GROUPS];
 };
 
 /*
@@ -447,9 +476,6 @@ struct driver_data {
 
 	struct mtip_port *port; /* Pointer to the port data structure. */
 
-	/* Tasklet used to process the bottom half of the ISR. */
-	struct tasklet_struct tasklet;
-
 	unsigned product_type; /* magic value declaring the product type */
 
 	unsigned slot_groups; /* number of slot groups the product supports */
@@ -461,6 +487,20 @@ struct driver_data {
 	struct task_struct *mtip_svc_handler; /* task_struct of svc thd */
 
 	struct dentry *dfs_node;
+
+	bool trim_supp; /* flag indicating trim support */
+
+	int numa_node; /* NUMA support */
+
+	char workq_name[32];
+
+	struct workqueue_struct *isr_workq;
+
+	struct mtip_work work[MTIP_MAX_SLOT_GROUPS];
+
+	atomic_t irq_workers_active;
+
+	int isr_binding;
 };
 
 #endif

drivers/block/rsxx/Makefile

+obj-$(CONFIG_BLK_DEV_RSXX) += rsxx.o
+rsxx-y := config.o core.o cregs.o dev.o dma.o

drivers/block/rsxx/config.c

+/*
+* Filename: config.c
+*
+*
+* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
+*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+*
+* (C) Copyright 2013 IBM Corporation
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful, but
+* WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software Foundation,
+* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <linux/types.h>
+#include <linux/crc32.h>
+#include <linux/swab.h>
+
+#include "rsxx_priv.h"
+#include "rsxx_cfg.h"
+
+static void initialize_config(void *config)
+{
+	struct rsxx_card_cfg *cfg = config;
+
+	cfg->hdr.version = RSXX_CFG_VERSION;
+
+	cfg->data.block_size        = RSXX_HW_BLK_SIZE;
+	cfg->data.stripe_size       = RSXX_HW_BLK_SIZE;
+	cfg->data.vendor_id         = RSXX_VENDOR_ID_TMS_IBM;
+	cfg->data.cache_order       = (-1);
+	cfg->data.intr_coal.mode    = RSXX_INTR_COAL_DISABLED;
+	cfg->data.intr_coal.count   = 0;
+	cfg->data.intr_coal.latency = 0;
+}
+
+static u32 config_data_crc32(struct rsxx_card_cfg *cfg)
+{
+	/*
+	 * Return the compliment of the CRC to ensure compatibility
+	 * (i.e. this is how early rsxx drivers did it.)
+	 */
+
+	return ~crc32(~0, &cfg->data, sizeof(cfg->data));
+}
+
+
+/*----------------- Config Byte Swap Functions -------------------*/
+static void config_hdr_be_to_cpu(struct card_cfg_hdr *hdr)
+{
+	hdr->version = be32_to_cpu((__force __be32) hdr->version);
+	hdr->crc     = be32_to_cpu((__force __be32) hdr->crc);
+}
+
+static void config_hdr_cpu_to_be(struct card_cfg_hdr *hdr)
+{
+	hdr->version = (__force u32) cpu_to_be32(hdr->version);
+	hdr->crc     = (__force u32) cpu_to_be32(hdr->crc);
+}
+
+static void config_data_swab(struct rsxx_card_cfg *cfg)
+{
+	u32 *data = (u32 *) &cfg->data;
+	int i;
+
+	for (i = 0; i < (sizeof(cfg->data) / 4); i++)
+		data[i] = swab32(data[i]);
+}
+
+static void config_data_le_to_cpu(struct rsxx_card_cfg *cfg)
+{
+	u32 *data = (u32 *) &cfg->data;
+	int i;
+
+	for (i = 0; i < (sizeof(cfg->data) / 4); i++)
+		data[i] = le32_to_cpu((__force __le32) data[i]);
+}
+
+static void config_data_cpu_to_le(struct rsxx_card_cfg *cfg)
+{
+	u32 *data = (u32 *) &cfg->data;
+	int i;
+
+	for (i = 0; i < (sizeof(cfg->data) / 4); i++)
+		data[i] = (__force u32) cpu_to_le32(data[i]);
+}
+
+
+/*----------------- Config Operations ------------------*/
+static int rsxx_save_config(struct rsxx_cardinfo *card)
+{
+	struct rsxx_card_cfg cfg;
+	int st;
+
+	memcpy(&cfg, &card->config, sizeof(cfg));
+
+	if (unlikely(cfg.hdr.version != RSXX_CFG_VERSION)) {
+		dev_err(CARD_TO_DEV(card),
+			"Cannot save config with invalid version %d\n",
+			cfg.hdr.version);
+		return -EINVAL;
+	}
+
+	/* Convert data to little endian for the CRC calculation. */
+	config_data_cpu_to_le(&cfg);
+
+	cfg.hdr.crc = config_data_crc32(&cfg);
+
+	/*
+	 * Swap the data from little endian to big endian so it can be
+	 * stored.
+	 */
+	config_data_swab(&cfg);
+	config_hdr_cpu_to_be(&cfg.hdr);
+
+	st = rsxx_creg_write(card, CREG_ADD_CONFIG, sizeof(cfg), &cfg, 1);
+	if (st)
+		return st;
+
+	return 0;
+}
+
+int rsxx_load_config(struct rsxx_cardinfo *card)
+{
+	int st;
+	u32 crc;
+
+	st = rsxx_creg_read(card, CREG_ADD_CONFIG, sizeof(card->config),
+				&card->config, 1);
+	if (st) {
+		dev_err(CARD_TO_DEV(card),
+			"Failed reading card config.\n");
+		return st;
+	}
+
+	config_hdr_be_to_cpu(&card->config.hdr);
+
+	if (card->config.hdr.version == RSXX_CFG_VERSION) {
+		/*
+		 * We calculate the CRC with the data in little endian, because
+		 * early drivers did not take big endian CPUs into account.
+		 * The data is always stored in big endian, so we need to byte
+		 * swap it before calculating the CRC.
+		 */
+
+		config_data_swab(&card->config);
+
+		/* Check the CRC */
+		crc = config_data_crc32(&card->config);
+		if (crc != card->config.hdr.crc) {
+			dev_err(CARD_TO_DEV(card),
+				"Config corruption detected!\n");
+			dev_info(CARD_TO_DEV(card),
+				"CRC (sb x%08x is x%08x)\n",
+				card->config.hdr.crc, crc);
+			return -EIO;
+		}
+
+		/* Convert the data to CPU byteorder */
+		config_data_le_to_cpu(&card->config);
+
+	} else if (card->config.hdr.version != 0) {
+		dev_err(CARD_TO_DEV(card),
+			"Invalid config version %d.\n",
+			card->config.hdr.version);
+		/*
+		 * Config version changes require special handling from the
+		 * user
+		 */
+		return -EINVAL;
+	} else {
+		dev_info(CARD_TO_DEV(card),
+			"Initializing card configuration.\n");
+		initialize_config(card);
+		st = rsxx_save_config(card);
+		if (st)
+			return st;
+	}
+
+	card->config_valid = 1;
+
+	dev_dbg(CARD_TO_DEV(card), "version:     x%08x\n",
+		card->config.hdr.version);
+	dev_dbg(CARD_TO_DEV(card), "crc:         x%08x\n",
+		card->config.hdr.crc);
+	dev_dbg(CARD_TO_DEV(card), "block_size:  x%08x\n",
+		card->config.data.block_size);
+	dev_dbg(CARD_TO_DEV(card), "stripe_size: x%08x\n",
+		card->config.data.stripe_size);
+	dev_dbg(CARD_TO_DEV(card), "vendor_id:   x%08x\n",
+		card->config.data.vendor_id);
+	dev_dbg(CARD_TO_DEV(card), "cache_order: x%08x\n",
+		card->config.data.cache_order);
+	dev_dbg(CARD_TO_DEV(card), "mode:        x%08x\n",
+		card->config.data.intr_coal.mode);
+	dev_dbg(CARD_TO_DEV(card), "count:       x%08x\n",
+		card->config.data.intr_coal.count);
+	dev_dbg(CARD_TO_DEV(card), "latency:     x%08x\n",
+		 card->config.data.intr_coal.latency);
+
+	return 0;
+}
+

drivers/block/rsxx/dev.c

+/*
+* Filename: dev.c
+*
+*
+* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
+*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+*
+* (C) Copyright 2013 IBM Corporation
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful, but
+* WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software Foundation,
+* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+
+#include <linux/hdreg.h>
+#include <linux/genhd.h>
+#include <linux/blkdev.h>
+#include <linux/bio.h>
+
+#include <linux/fs.h>
+
+#include "rsxx_priv.h"
+
+static unsigned int blkdev_minors = 64;
+module_param(blkdev_minors, uint, 0444);
+MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)");
+
+/*
+ * For now I'm making this tweakable in case any applications hit this limit.
+ * If you see a "bio too big" error in the log you will need to raise this
+ * value.
+ */
+static unsigned int blkdev_max_hw_sectors = 1024;
+module_param(blkdev_max_hw_sectors, uint, 0444);
+MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO");
+
+static unsigned int enable_blkdev = 1;
+module_param(enable_blkdev , uint, 0444);
+MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");
+
+
+struct rsxx_bio_meta {
+	struct bio	*bio;
+	atomic_t	pending_dmas;
+	atomic_t	error;
+	unsigned long	start_time;
+};
+
+static struct kmem_cache *bio_meta_pool;
+
+/*----------------- Block Device Operations -----------------*/
+static int rsxx_blkdev_ioctl(struct block_device *bdev,
+				 fmode_t mode,
+				 unsigned int cmd,
+				 unsigned long arg)
+{
+	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
+
+	switch (cmd) {
+	case RSXX_GETREG:
+		return rsxx_reg_access(card, (void __user *)arg, 1);
+	case RSXX_SETREG:
+		return rsxx_reg_access(card, (void __user *)arg, 0);
+	}
+
+	return -ENOTTY;
+}
+
+static int rsxx_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
+	u64 blocks = card->size8 >> 9;
+
+	/*
+	 * get geometry: Fake it. I haven't found any drivers that set
+	 * geo->start, so we won't either.
+	 */
+	if (card->size8) {
+		geo->heads = 64;
+		geo->sectors = 16;
+		do_div(blocks, (geo->heads * geo->sectors));
+		geo->cylinders = blocks;
+	} else {
+		geo->heads = 0;
+		geo->sectors = 0;
+		geo->cylinders = 0;
+	}
+	return 0;
+}
+
+static const struct block_device_operations rsxx_fops = {
+	.owner		= THIS_MODULE,
+	.getgeo		= rsxx_getgeo,
+	.ioctl		= rsxx_blkdev_ioctl,
+};
+
+static void disk_stats_start(struct rsxx_cardinfo *card, struct bio *bio)
+{
+	struct hd_struct *part0 = &card->gendisk->part0;
+	int rw = bio_data_dir(bio);
+	int cpu;
+
+	cpu = part_stat_lock();
+
+	part_round_stats(cpu, part0);
+	part_inc_in_flight(part0, rw);
+
+	part_stat_unlock();
+}
+
+static void disk_stats_complete(struct rsxx_cardinfo *card,
+				struct bio *bio,
+				unsigned long start_time)
+{
+	struct hd_struct *part0 = &card->gendisk->part0;
+	unsigned long duration = jiffies - start_time;
+	int rw = bio_data_dir(bio);
+	int cpu;
+
+	cpu = part_stat_lock();
+
+	part_stat_add(cpu, part0, sectors[rw], bio_sectors(bio));
+	part_stat_inc(cpu, part0, ios[rw]);
+	part_stat_add(cpu, part0, ticks[rw], duration);
+
+	part_round_stats(cpu, part0);
+	part_dec_in_flight(part0, rw);
+
+	part_stat_unlock();
+}
+
+static void bio_dma_done_cb(struct rsxx_cardinfo *card,
+			    void *cb_data,
+			    unsigned int error)
+{
+	struct rsxx_bio_meta *meta = cb_data;
+
+	if (error)
+		atomic_set(&meta->error, 1);
+
+	if (atomic_dec_and_test(&meta->pending_dmas)) {
+		disk_stats_complete(card, meta->bio, meta->start_time);
+
+		bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
+		kmem_cache_free(bio_meta_pool, meta);
+	}
+}
+
+static void rsxx_make_request(struct request_queue *q, struct bio *bio)
+{
+	struct rsxx_cardinfo *card = q->queuedata;
+	struct rsxx_bio_meta *bio_meta;
+	int st = -EINVAL;
+
+	might_sleep();
+
+	if (unlikely(card->halt)) {
+		st = -EFAULT;
+		goto req_err;
+	}
+
+	if (unlikely(card->dma_fault)) {
+		st = (-EFAULT);
+		goto req_err;
+	}
+
+	if (bio->bi_size == 0) {
+		dev_err(CARD_TO_DEV(card), "size zero BIO!\n");
+		goto req_err;
+	}
+
+	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);
+	if (!bio_meta) {
+		st = -ENOMEM;
+		goto req_err;
+	}
+
+	bio_meta->bio = bio;
+	atomic_set(&bio_meta->error, 0);
+	atomic_set(&bio_meta->pending_dmas, 0);
+	bio_meta->start_time = jiffies;
+
+	disk_stats_start(card, bio);
+
+	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",
+		 bio_data_dir(bio) ? 'W' : 'R', bio_meta,
+		 (u64)bio->bi_sector << 9, bio->bi_size);
+
+	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,
+				    bio_dma_done_cb, bio_meta);
+	if (st)
+		goto queue_err;
+
+	return;
+
+queue_err:
+	kmem_cache_free(bio_meta_pool, bio_meta);
+req_err:
+	bio_endio(bio, st);
+}
+
+/*----------------- Device Setup -------------------*/
+static bool rsxx_discard_supported(struct rsxx_cardinfo *card)
+{
+	unsigned char pci_rev;
+
+	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev);
+
+	return (pci_rev >= RSXX_DISCARD_SUPPORT);
+}
+
+static unsigned short rsxx_get_logical_block_size(
+					struct rsxx_cardinfo *card)
+{
+	u32 capabilities = 0;
+	int st;
+
+	st = rsxx_get_card_capabilities(card, &capabilities);
+	if (st)
+		dev_warn(CARD_TO_DEV(card),
+			"Failed reading card capabilities register\n");
+
+	/* Earlier firmware did not have support for 512 byte accesses */
+	if (capabilities & CARD_CAP_SUBPAGE_WRITES)
+		return 512;
+	else
+		return RSXX_HW_BLK_SIZE;
+}
+
+int rsxx_attach_dev(struct rsxx_cardinfo *card)
+{
+	mutex_lock(&card->dev_lock);
+
+	/* The block device requires the stripe size from the config. */
+	if (enable_blkdev) {
+		if (card->config_valid)
+			set_capacity(card->gendisk, card->size8 >> 9);
+		else
+			set_capacity(card->gendisk, 0);
+		add_disk(card->gendisk);
+
+		card->bdev_attached = 1;
+	}
+
+	mutex_unlock(&card->dev_lock);
+
+	return 0;
+}
+
+void rsxx_detach_dev(struct rsxx_cardinfo *card)
+{
+	mutex_lock(&card->dev_lock);
+
+	if (card->bdev_attached) {
+		del_gendisk(card->gendisk);
+		card->bdev_attached = 0;
+	}
+
+	mutex_unlock(&card->dev_lock);
+}
+
+int rsxx_setup_dev(struct rsxx_cardinfo *card)
+{
+	unsigned short blk_size;
+
+	mutex_init(&card->dev_lock);
+
+	if (!enable_blkdev)
+		return 0;
+
+	card->major = register_blkdev(0, DRIVER_NAME);
+	if (card->major < 0) {
+		dev_err(CARD_TO_DEV(card), "Failed to get major number\n");
+		return -ENOMEM;
+	}
+
+	card->queue = blk_alloc_queue(GFP_KERNEL);
+	if (!card->queue) {
+		dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");
+		unregister_blkdev(card->major, DRIVER_NAME);
+		return -ENOMEM;
+	}
+
+	card->gendisk = alloc_disk(blkdev_minors);
+	if (!card->gendisk) {
+		dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");
+		blk_cleanup_queue(card->queue);
+		unregister_blkdev(card->major, DRIVER_NAME);
+		return -ENOMEM;
+	}
+
+	blk_size = rsxx_get_logical_block_size(card);
+
+	blk_queue_make_request(card->queue, rsxx_make_request);
+	blk_queue_bounce_limit(card->queue, BLK_BOUNCE_ANY);
+	blk_queue_dma_alignment(card->queue, blk_size - 1);
+	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);
+	blk_queue_logical_block_size(card->queue, blk_size);
+	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE);
+
+	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);
+	if (rsxx_discard_supported(card)) {
+		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);
+		blk_queue_max_discard_sectors(card->queue,
+						RSXX_HW_BLK_SIZE >> 9);
+		card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;
+		card->queue->limits.discard_alignment   = RSXX_HW_BLK_SIZE;
+		card->queue->limits.discard_zeroes_data = 1;
+	}
+
+	card->queue->queuedata = card;
+
+	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
+		 "rsxx%d", card->disk_id);
+	card->gendisk->driverfs_dev = &card->dev->dev;
+	card->gendisk->major = card->major;
+	card->gendisk->first_minor = 0;
+	card->gendisk->fops = &rsxx_fops;
+	card->gendisk->private_data = card;
+	card->gendisk->queue = card->queue;
+
+	return 0;
+}
+
+void rsxx_destroy_dev(struct rsxx_cardinfo *card)
+{
+	if (!enable_blkdev)
+		return;
+
+	put_disk(card->gendisk);
+	card->gendisk = NULL;
+
+	blk_cleanup_queue(card->queue);
+	unregister_blkdev(card->major, DRIVER_NAME);
+}
+
+int rsxx_dev_init(void)
+{
+	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);
+	if (!bio_meta_pool)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void rsxx_dev_cleanup(void)
+{
+	kmem_cache_destroy(bio_meta_pool);
+}
+
+

drivers/block/rsxx/rsxx.h

+/*
+* Filename: rsxx.h
+*
+*
+* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
+*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+*
+* (C) Copyright 2013 IBM Corporation
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful, but
+* WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software Foundation,
+* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#ifndef __RSXX_H__
+#define __RSXX_H__
+
+/*----------------- IOCTL Definitions -------------------*/
+
+struct rsxx_reg_access {
+	__u32 addr;
+	__u32 cnt;
+	__u32 stat;
+	__u32 stream;
+	__u32 data[8];
+};
+
+#define RSXX_MAX_REG_CNT	(8 * (sizeof(__u32)))
+
+#define RSXX_IOC_MAGIC 'r'
+
+#define RSXX_GETREG _IOWR(RSXX_IOC_MAGIC, 0x20, struct rsxx_reg_access)
+#define RSXX_SETREG _IOWR(RSXX_IOC_MAGIC, 0x21, struct rsxx_reg_access)
+
+#endif /* __RSXX_H_ */

drivers/block/rsxx/rsxx_cfg.h

+/*
+* Filename: rsXX_cfg.h
+*
+*
+* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
+*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
+*
+* (C) Copyright 2013 IBM Corporation
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of the
+* License, or (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful, but
+* WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software Foundation,
+* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#ifndef __RSXX_CFG_H__
+#define __RSXX_CFG_H__
+
+/* NOTE: Config values will be saved in network byte order (i.e. Big endian) */
+#include <linux/types.h>
+
+/*
+ * The card config version must match the driver's expected version. If it does
+ * not, the DMA interfaces will not be attached and the user will need to
+ * initialize/upgrade the card configuration using the card config utility.
+ */
+#define RSXX_CFG_VERSION	4
+
+struct card_cfg_hdr {
+	__u32	version;
+	__u32	crc;
+};
+
+struct card_cfg_data {
+	__u32	block_size;
+	__u32	stripe_size;
+	__u32	vendor_id;
+	__u32	cache_order;
+	struct {
+		__u32	mode;	/* Disabled, manual, auto-tune... */
+		__u32	count;	/* Number of intr to coalesce     */
+		__u32	latency;/* Max wait time (in ns)          */
+	} intr_coal;
+};
+
+struct rsxx_card_cfg {
+	struct card_cfg_hdr	hdr;
+	struct card_cfg_data	data;
+};
+
+/* Vendor ID Values */
+#define RSXX_VENDOR_ID_TMS_IBM		0
+#define RSXX_VENDOR_ID_DSI		1
+#define RSXX_VENDOR_COUNT		2
+
+/* Interrupt Coalescing Values */
+#define RSXX_INTR_COAL_DISABLED           0
+#define RSXX_INTR_COAL_EXPLICIT           1
+#define RSXX_INTR_COAL_AUTO_TUNE          2
+
+
+#endif /* __RSXX_CFG_H__ */
+

drivers/block/xd.h

-#ifndef _LINUX_XD_H
-#define _LINUX_XD_H
-
-/*
- * This file contains the definitions for the IO ports and errors etc. for XT hard disk controllers (at least the DTC 5150X).
- *
- * Author: Pat Mackinlay, pat@it.com.au
- * Date: 29/09/92
- *
- * Revised: 01/01/93, ...
- *
- * Ref: DTC 5150X Controller Specification (thanks to Kevin Fowler, kevinf@agora.rain.com)
- * Also thanks to: Salvador Abreu, Dave Thaler, Risto Kankkunen and Wim Van Dorst.
- */
-
-#include <linux/interrupt.h>
-
-/* XT hard disk controller registers */
-#define XD_DATA		(xd_iobase + 0x00)	/* data RW register */
-#define XD_RESET	(xd_iobase + 0x01)	/* reset WO register */
-#define XD_STATUS	(xd_iobase + 0x01)	/* status RO register */
-#define XD_SELECT	(xd_iobase + 0x02)	/* select WO register */
-#define XD_JUMPER	(xd_iobase + 0x02)	/* jumper RO register */
-#define XD_CONTROL	(xd_iobase + 0x03)	/* DMAE/INTE WO register */
-#define XD_RESERVED	(xd_iobase + 0x03)	/* reserved */
-
-/* XT hard disk controller commands (incomplete list) */
-#define CMD_TESTREADY	0x00	/* test drive ready */
-#define CMD_RECALIBRATE	0x01	/* recalibrate drive */
-#define CMD_SENSE	0x03	/* request sense */
-#define CMD_FORMATDRV	0x04	/* format drive */
-#define CMD_VERIFY	0x05	/* read verify */
-#define CMD_FORMATTRK	0x06	/* format track */
-#define CMD_FORMATBAD	0x07	/* format bad track */
-#define CMD_READ	0x08	/* read */
-#define CMD_WRITE	0x0A	/* write */
-#define CMD_SEEK	0x0B	/* seek */
-
-/* Controller specific commands */
-#define CMD_DTCSETPARAM	0x0C	/* set drive parameters (DTC 5150X & CX only?) */
-#define CMD_DTCGETECC	0x0D	/* get ecc error length (DTC 5150X only?) */
-#define CMD_DTCREADBUF	0x0E	/* read sector buffer (DTC 5150X only?) */
-#define CMD_DTCWRITEBUF 0x0F	/* write sector buffer (DTC 5150X only?) */
-#define CMD_DTCREMAPTRK	0x11	/* assign alternate track (DTC 5150X only?) */
-#define CMD_DTCGETPARAM	0xFB	/* get drive parameters (DTC 5150X only?) */
-#define CMD_DTCSETSTEP	0xFC	/* set step rate (DTC 5150X only?) */
-#define CMD_DTCSETGEOM	0xFE	/* set geometry data (DTC 5150X only?) */
-#define CMD_DTCGETGEOM	0xFF	/* get geometry data (DTC 5150X only?) */
-#define CMD_ST11GETGEOM 0xF8	/* get geometry data (Seagate ST11R/M only?) */
-#define CMD_WDSETPARAM	0x0C	/* set drive parameters (WD 1004A27X only?) */
-#define CMD_XBSETPARAM	0x0C	/* set drive parameters (XEBEC only?) */
-
-/* Bits for command status byte */
-#define CSB_ERROR	0x02	/* error */
-#define CSB_LUN		0x20	/* logical Unit Number */
-
-/* XT hard disk controller status bits */
-#define STAT_READY	0x01	/* controller is ready */
-#define STAT_INPUT	0x02	/* data flowing from controller to host */
-#define STAT_COMMAND	0x04	/* controller in command phase */
-#define STAT_SELECT	0x08	/* controller is selected */
-#define STAT_REQUEST	0x10	/* controller requesting data */
-#define STAT_INTERRUPT	0x20	/* controller requesting interrupt */
-
-/* XT hard disk controller control bits */
-#define PIO_MODE	0x00	/* control bits to set for PIO */
-#define DMA_MODE	0x03	/* control bits to set for DMA & interrupt */
-
-#define XD_MAXDRIVES	2	/* maximum 2 drives */
-#define XD_TIMEOUT	HZ	/* 1 second timeout */
-#define XD_RETRIES	4	/* maximum 4 retries */
-
-#undef DEBUG			/* define for debugging output */
-
-#ifdef DEBUG
-	#define DEBUG_STARTUP	/* debug driver initialisation */
-	#define DEBUG_OVERRIDE	/* debug override geometry detection */
-	#define DEBUG_READWRITE	/* debug each read/write command */
-	#define DEBUG_OTHER	/* debug misc. interrupt/DMA stuff */
-	#define DEBUG_COMMAND	/* debug each controller command */
-#endif /* DEBUG */
-
-/* this structure defines the XT drives and their types */
-typedef struct {
-	u_char heads;
-	u_short cylinders;
-	u_char sectors;
-	u_char control;
-	int unit;
-} XD_INFO;
-
-/* this structure defines a ROM BIOS signature */
-typedef struct {
-	unsigned int offset;
-	const char *string;
-	void (*init_controller)(unsigned int address);
-	void (*init_drive)(u_char drive);
-	const char *name;
-} XD_SIGNATURE;
-
-#ifndef MODULE
-static int xd_manual_geo_init (char *command);
-#endif /* MODULE */
-static u_char xd_detect (u_char *controller, unsigned int *address);
-static u_char xd_initdrives (void (*init_drive)(u_char drive));
-
-static void do_xd_request (struct request_queue * q);
-static int xd_ioctl (struct block_device *bdev,fmode_t mode,unsigned int cmd,unsigned long arg);
-static int xd_readwrite (u_char operation,XD_INFO *disk,char *buffer,u_int block,u_int count);
-static void xd_recalibrate (u_char drive);
-
-static irqreturn_t xd_interrupt_handler(int irq, void *dev_id);
-static u_char xd_setup_dma (u_char opcode,u_char *buffer,u_int count);
-static u_char *xd_build (u_char *cmdblk,u_char command,u_char drive,u_char head,u_short cylinder,u_char sector,u_char count,u_char control);
-static void xd_watchdog (unsigned long unused);
-static inline u_char xd_waitport (u_short port,u_char flags,u_char mask,u_long timeout);
-static u_int xd_command (u_char *command,u_char mode,u_char *indata,u_char *outdata,u_char *sense,u_long timeout);
-
-/* card specific setup and geometry gathering code */
-static void xd_dtc_init_controller (unsigned int address);
-static void xd_dtc5150cx_init_drive (u_char drive);
-static void xd_dtc_init_drive (u_char drive);
-static void xd_wd_init_controller (unsigned int address);
-static void xd_wd_init_drive (u_char drive);
-static void xd_seagate_init_controller (unsigned int address);
-static void xd_seagate_init_drive (u_char drive);
-static void xd_omti_init_controller (unsigned int address);
-static void xd_omti_init_drive (u_char drive);
-static void xd_xebec_init_controller (unsigned int address);
-static void xd_xebec_init_drive (u_char drive);
-static void xd_setparam (u_char command,u_char drive,u_char heads,u_short cylinders,u_short rwrite,u_short wprecomp,u_char ecc);
-static void xd_override_init_drive (u_char drive);
-
-#endif /* _LINUX_XD_H */

drivers/block/xen-blkback/blkback.c

@@ -46,6 +46,7 @@
 #include <xen/xen.h>
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
+#include <xen/balloon.h>
 #include "common.h"
 
 /*
@@ -239,6 +240,7 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num)
 			ret = gnttab_unmap_refs(unmap, NULL, pages,
 				segs_to_unmap);
 			BUG_ON(ret);
+			free_xenballooned_pages(segs_to_unmap, pages);
 			segs_to_unmap = 0;
 		}
 
@@ -527,8 +529,8 @@ static int xen_blkbk_map(struct blkif_request *req,
 				GFP_KERNEL);
 			if (!persistent_gnt)
 				return -ENOMEM;
-			persistent_gnt->page = alloc_page(GFP_KERNEL);
-			if (!persistent_gnt->page) {
+			if (alloc_xenballooned_pages(1, &persistent_gnt->page,
+			    false)) {
 				kfree(persistent_gnt);
 				return -ENOMEM;
 			}
@@ -879,7 +881,6 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 		goto fail_response;
 	}
 
-	preq.dev           = req->u.rw.handle;
 	preq.sector_number = req->u.rw.sector_number;
 	preq.nr_sects      = 0;
 

drivers/block/xen-blkback/xenbus.c

@@ -367,6 +367,7 @@ static int xen_blkbk_remove(struct xenbus_device *dev)
 		be->blkif = NULL;
 	}
 
+	kfree(be->mode);
 	kfree(be);
 	dev_set_drvdata(&dev->dev, NULL);
 	return 0;
@@ -502,6 +503,7 @@ static void backend_changed(struct xenbus_watch *watch,
 		= container_of(watch, struct backend_info, backend_watch);
 	struct xenbus_device *dev = be->dev;
 	int cdrom = 0;
+	unsigned long handle;
 	char *device_type;
 
 	DPRINTK("");
@@ -521,8 +523,8 @@ static void backend_changed(struct xenbus_watch *watch,
 		return;
 	}
 
-	if ((be->major || be->minor) &&
-	    ((be->major != major) || (be->minor != minor))) {
+	if (be->major | be->minor) {
+		if (be->major != major || be->minor != minor)
 			pr_warn(DRV_PFX "changing physical device (from %x:%x to %x:%x) not supported.\n",
 				be->major, be->minor, major, minor);
 		return;
@@ -542,12 +544,8 @@ static void backend_changed(struct xenbus_watch *watch,
 		kfree(device_type);
 	}
 
-	if (be->major == 0 && be->minor == 0) {
 	/* Front end dir is a number, which is used as the handle. */
-
-		char *p = strrchr(dev->otherend, '/') + 1;
-		long handle;
-		err = strict_strtoul(p, 0, &handle);
+	err = strict_strtoul(strrchr(dev->otherend, '/') + 1, 0, &handle);
 	if (err)
 		return;
 
@@ -555,23 +553,24 @@ static void backend_changed(struct xenbus_watch *watch,
 	be->minor = minor;
 
 	err = xen_vbd_create(be->blkif, handle, major, minor,
-				 (NULL == strchr(be->mode, 'w')), cdrom);
-		if (err) {
-			be->major = 0;
-			be->minor = 0;
-			xenbus_dev_fatal(dev, err, "creating vbd structure");
-			return;
-		}
+			     !strchr(be->mode, 'w'), cdrom);
 
+	if (err)
+		xenbus_dev_fatal(dev, err, "creating vbd structure");
+	else {
 		err = xenvbd_sysfs_addif(dev);
 		if (err) {
 			xen_vbd_free(&be->blkif->vbd);
-			be->major = 0;
-			be->minor = 0;
 			xenbus_dev_fatal(dev, err, "creating sysfs entries");
-			return;
+		}
 	}
 
+	if (err) {
+		kfree(be->mode);
+		be->mode = NULL;
+		be->major = 0;
+		be->minor = 0;
+	} else {
 		/* We're potentially connected now */
 		xen_update_blkif_status(be->blkif);
 	}

drivers/block/xen-blkfront.c

@@ -791,7 +791,7 @@ static void blkif_restart_queue(struct work_struct *work)
 static void blkif_free(struct blkfront_info *info, int suspend)
 {
 	struct llist_node *all_gnts;
-	struct grant *persistent_gnt;
+	struct grant *persistent_gnt, *tmp;
 	struct llist_node *n;
 
 	/* Prevent new requests being issued until we fix things up. */
@@ -805,10 +805,17 @@ static void blkif_free(struct blkfront_info *info, int suspend)
 	/* Remove all persistent grants */
 	if (info->persistent_gnts_c) {
 		all_gnts = llist_del_all(&info->persistent_gnts);
-		llist_for_each_entry_safe(persistent_gnt, n, all_gnts, node) {
+		persistent_gnt = llist_entry(all_gnts, typeof(*(persistent_gnt)), node);
+		while (persistent_gnt) {
 			gnttab_end_foreign_access(persistent_gnt->gref, 0, 0UL);
 			__free_page(pfn_to_page(persistent_gnt->pfn));
-			kfree(persistent_gnt);
+			tmp = persistent_gnt;
+			n = persistent_gnt->node.next;
+			if (n)
+				persistent_gnt = llist_entry(n, typeof(*(persistent_gnt)), node);
+			else
+				persistent_gnt = NULL;
+			kfree(tmp);
 		}
 		info->persistent_gnts_c = 0;
 	}

include/linux/llist.h

@@ -124,31 +124,6 @@ static inline void init_llist_head(struct llist_head *list)
 	     &(pos)->member != NULL;					\
 	     (pos) = llist_entry((pos)->member.next, typeof(*(pos)), member))
 
-/**
- * llist_for_each_entry_safe - iterate safely against remove over some entries
- * of lock-less list of given type.
- * @pos:	the type * to use as a loop cursor.
- * @n:		another type * to use as a temporary storage.
- * @node:	the fist entry of deleted list entries.
- * @member:	the name of the llist_node with the struct.
- *
- * In general, some entries of the lock-less list can be traversed
- * safely only after being removed from list, so start with an entry
- * instead of list head. This variant allows removal of entries
- * as we iterate.
- *
- * If being used on entries deleted from lock-less list directly, the
- * traverse order is from the newest to the oldest added entry.  If
- * you want to traverse from the oldest to the newest, you must
- * reverse the order by yourself before traversing.
- */
-#define llist_for_each_entry_safe(pos, n, node, member)		\
-	for ((pos) = llist_entry((node), typeof(*(pos)), member),	\
-	     (n) = (pos)->member.next;					\
-	     &(pos)->member != NULL;					\
-	     (pos) = llist_entry(n, typeof(*(pos)), member),		\
-	     (n) = (&(pos)->member != NULL) ? (pos)->member.next : NULL)
-
 /**
  * llist_empty - tests whether a lock-less list is empty
  * @head:	the list to test