[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/drivers/scsi/sd.c b/ap/os/linux/linux-3.4.x/drivers/scsi/sd.c
new file mode 100644
index 0000000..97aa6c6
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/scsi/sd.c
@@ -0,0 +1,2995 @@
+/*
+ *      sd.c Copyright (C) 1992 Drew Eckhardt
+ *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
+ *
+ *      Linux scsi disk driver
+ *              Initial versions: Drew Eckhardt
+ *              Subsequent revisions: Eric Youngdale
+ *	Modification history:
+ *       - Drew Eckhardt <drew@colorado.edu> original
+ *       - Eric Youngdale <eric@andante.org> add scatter-gather, multiple 
+ *         outstanding request, and other enhancements.
+ *         Support loadable low-level scsi drivers.
+ *       - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using 
+ *         eight major numbers.
+ *       - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
+ *	 - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in 
+ *	   sd_init and cleanups.
+ *	 - Alex Davis <letmein@erols.com> Fix problem where partition info
+ *	   not being read in sd_open. Fix problem where removable media 
+ *	   could be ejected after sd_open.
+ *	 - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5.x
+ *	 - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox 
+ *	   <willy@debian.org>, Kurt Garloff <garloff@suse.de>: 
+ *	   Support 32k/1M disks.
+ *
+ *	Logging policy (needs CONFIG_SCSI_LOGGING defined):
+ *	 - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
+ *	 - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
+ *	 - entering sd_ioctl: SCSI_LOG_IOCTL level 1
+ *	 - entering other commands: SCSI_LOG_HLQUEUE level 3
+ *	Note: when the logging level is set by the user, it must be greater
+ *	than the level indicated above to trigger output.	
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/bio.h>
+#include <linux/genhd.h>
+#include <linux/hdreg.h>
+#include <linux/errno.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/blkpg.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/string_helpers.h>
+#include <linux/async.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <asm/uaccess.h>
+#include <asm/unaligned.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_ioctl.h>
+#include <scsi/scsicam.h>
+
+#include "sd.h"
+#include "scsi_logging.h"
+
+MODULE_AUTHOR("Eric Youngdale");
+MODULE_DESCRIPTION("SCSI disk (sd) driver");
+MODULE_LICENSE("GPL");
+
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
+MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
+MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
+
+#if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
+#define SD_MINORS	16
+#else
+#define SD_MINORS	0
+#endif
+
+static void sd_config_discard(struct scsi_disk *, unsigned int);
+static int  sd_revalidate_disk(struct gendisk *);
+static void sd_unlock_native_capacity(struct gendisk *disk);
+static int  sd_probe(struct device *);
+static int  sd_remove(struct device *);
+static void sd_shutdown(struct device *);
+static int sd_suspend(struct device *, pm_message_t state);
+static int sd_resume(struct device *);
+static void sd_rescan(struct device *);
+static int sd_done(struct scsi_cmnd *);
+static int sd_eh_action(struct scsi_cmnd *, unsigned char *, int, int);
+static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
+static void scsi_disk_release(struct device *cdev);
+static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
+static void sd_print_result(struct scsi_disk *, int);
+
+static DEFINE_SPINLOCK(sd_index_lock);
+static DEFINE_IDA(sd_index_ida);
+
+/* This semaphore is used to mediate the 0->1 reference get in the
+ * face of object destruction (i.e. we can't allow a get on an
+ * object after last put) */
+static DEFINE_MUTEX(sd_ref_mutex);
+
+static struct kmem_cache *sd_cdb_cache;
+static mempool_t *sd_cdb_pool;
+
+static const char *sd_cache_types[] = {
+	"write through", "none", "write back",
+	"write back, no read (daft)"
+};
+
+static ssize_t
+sd_store_cache_type(struct device *dev, struct device_attribute *attr,
+		    const char *buf, size_t count)
+{
+	int i, ct = -1, rcd, wce, sp;
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+	char buffer[64];
+	char *buffer_data;
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+	static const char temp[] = "temporary ";
+	int len;
+
+	if (sdp->type != TYPE_DISK)
+		/* no cache control on RBC devices; theoretically they
+		 * can do it, but there's probably so many exceptions
+		 * it's not worth the risk */
+		return -EINVAL;
+
+	if (strncmp(buf, temp, sizeof(temp) - 1) == 0) {
+		buf += sizeof(temp) - 1;
+		sdkp->cache_override = 1;
+	} else {
+		sdkp->cache_override = 0;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
+		len = strlen(sd_cache_types[i]);
+		if (strncmp(sd_cache_types[i], buf, len) == 0 &&
+		    buf[len] == '\n') {
+			ct = i;
+			break;
+		}
+	}
+	if (ct < 0)
+		return -EINVAL;
+	rcd = ct & 0x01 ? 1 : 0;
+	wce = ct & 0x02 ? 1 : 0;
+
+	if (sdkp->cache_override) {
+		sdkp->WCE = wce;
+		sdkp->RCD = rcd;
+		return count;
+	}
+
+	if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
+			    SD_MAX_RETRIES, &data, NULL))
+		return -EINVAL;
+	len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
+		  data.block_descriptor_length);
+	buffer_data = buffer + data.header_length +
+		data.block_descriptor_length;
+	buffer_data[2] &= ~0x05;
+	buffer_data[2] |= wce << 2 | rcd;
+	sp = buffer_data[0] & 0x80 ? 1 : 0;
+
+	if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
+			     SD_MAX_RETRIES, &data, &sshdr)) {
+		if (scsi_sense_valid(&sshdr))
+			sd_print_sense_hdr(sdkp, &sshdr);
+		return -EINVAL;
+	}
+	revalidate_disk(sdkp->disk);
+	return count;
+}
+
+static ssize_t
+sd_store_manage_start_stop(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
+
+	return count;
+}
+
+static ssize_t
+sd_store_allow_restart(struct device *dev, struct device_attribute *attr,
+		       const char *buf, size_t count)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (sdp->type != TYPE_DISK)
+		return -EINVAL;
+
+	sdp->allow_restart = simple_strtoul(buf, NULL, 10);
+
+	return count;
+}
+
+static ssize_t
+sd_show_cache_type(struct device *dev, struct device_attribute *attr,
+		   char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	int ct = sdkp->RCD + 2*sdkp->WCE;
+
+	return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
+}
+
+static ssize_t
+sd_show_fua(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
+}
+
+static ssize_t
+sd_show_manage_start_stop(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+
+	return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
+}
+
+static ssize_t
+sd_show_allow_restart(struct device *dev, struct device_attribute *attr,
+		      char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
+}
+
+static ssize_t
+sd_show_protection_type(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->protection_type);
+}
+
+static ssize_t
+sd_show_protection_mode(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+	unsigned int dif, dix;
+
+	dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
+	dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
+
+	if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
+		dif = 0;
+		dix = 1;
+	}
+
+	if (!dif && !dix)
+		return snprintf(buf, 20, "none\n");
+
+	return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
+}
+
+static ssize_t
+sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
+		    char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->ATO);
+}
+
+static ssize_t
+sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->lbpme);
+}
+
+static const char *lbp_mode[] = {
+	[SD_LBP_FULL]		= "full",
+	[SD_LBP_UNMAP]		= "unmap",
+	[SD_LBP_WS16]		= "writesame_16",
+	[SD_LBP_WS10]		= "writesame_10",
+	[SD_LBP_ZERO]		= "writesame_zero",
+	[SD_LBP_DISABLE]	= "disabled",
+};
+
+static ssize_t
+sd_show_provisioning_mode(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
+}
+
+static ssize_t
+sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct scsi_device *sdp = sdkp->device;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (sdp->type != TYPE_DISK)
+		return -EINVAL;
+
+	if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
+		sd_config_discard(sdkp, SD_LBP_UNMAP);
+	else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
+		sd_config_discard(sdkp, SD_LBP_WS16);
+	else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
+		sd_config_discard(sdkp, SD_LBP_WS10);
+	else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
+		sd_config_discard(sdkp, SD_LBP_ZERO);
+	else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
+		sd_config_discard(sdkp, SD_LBP_DISABLE);
+	else
+		return -EINVAL;
+
+	return count;
+}
+
+static ssize_t
+sd_show_max_medium_access_timeouts(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->max_medium_access_timeouts);
+}
+
+static ssize_t
+sd_store_max_medium_access_timeouts(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	int err;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	err = kstrtouint(buf, 10, &sdkp->max_medium_access_timeouts);
+
+	return err ? err : count;
+}
+
+static struct device_attribute sd_disk_attrs[] = {
+	__ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
+	       sd_store_cache_type),
+	__ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
+	__ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
+	       sd_store_allow_restart),
+	__ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
+	       sd_store_manage_start_stop),
+	__ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
+	__ATTR(protection_mode, S_IRUGO, sd_show_protection_mode, NULL),
+	__ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
+	__ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
+	__ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode,
+	       sd_store_provisioning_mode),
+	__ATTR(max_medium_access_timeouts, S_IRUGO|S_IWUSR,
+	       sd_show_max_medium_access_timeouts,
+	       sd_store_max_medium_access_timeouts),
+	__ATTR_NULL,
+};
+
+static struct class sd_disk_class = {
+	.name		= "scsi_disk",
+	.owner		= THIS_MODULE,
+	.dev_release	= scsi_disk_release,
+	.dev_attrs	= sd_disk_attrs,
+};
+
+static struct scsi_driver sd_template = {
+	.owner			= THIS_MODULE,
+	.gendrv = {
+		.name		= "sd",
+		.probe		= sd_probe,
+		.remove		= sd_remove,
+		.suspend	= sd_suspend,
+		.resume		= sd_resume,
+		.shutdown	= sd_shutdown,
+	},
+	.rescan			= sd_rescan,
+	.done			= sd_done,
+	.eh_action		= sd_eh_action,
+};
+
+/*
+ * Device no to disk mapping:
+ * 
+ *       major         disc2     disc  p1
+ *   |............|.............|....|....| <- dev_t
+ *    31        20 19          8 7  4 3  0
+ * 
+ * Inside a major, we have 16k disks, however mapped non-
+ * contiguously. The first 16 disks are for major0, the next
+ * ones with major1, ... Disk 256 is for major0 again, disk 272 
+ * for major1, ... 
+ * As we stay compatible with our numbering scheme, we can reuse 
+ * the well-know SCSI majors 8, 65--71, 136--143.
+ */
+static int sd_major(int major_idx)
+{
+	switch (major_idx) {
+	case 0:
+		return SCSI_DISK0_MAJOR;
+	case 1 ... 7:
+		return SCSI_DISK1_MAJOR + major_idx - 1;
+	case 8 ... 15:
+		return SCSI_DISK8_MAJOR + major_idx - 8;
+	default:
+		BUG();
+		return 0;	/* shut up gcc */
+	}
+}
+
+static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
+{
+	struct scsi_disk *sdkp = NULL;
+
+	if (disk->private_data) {
+		sdkp = scsi_disk(disk);
+		if (scsi_device_get(sdkp->device) == 0)
+			get_device(&sdkp->dev);
+		else
+			sdkp = NULL;
+	}
+	return sdkp;
+}
+
+static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
+{
+	struct scsi_disk *sdkp;
+
+	mutex_lock(&sd_ref_mutex);
+	sdkp = __scsi_disk_get(disk);
+	mutex_unlock(&sd_ref_mutex);
+	return sdkp;
+}
+
+static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
+{
+	struct scsi_disk *sdkp;
+
+	mutex_lock(&sd_ref_mutex);
+	sdkp = dev_get_drvdata(dev);
+	if (sdkp)
+		sdkp = __scsi_disk_get(sdkp->disk);
+	mutex_unlock(&sd_ref_mutex);
+	return sdkp;
+}
+
+static void scsi_disk_put(struct scsi_disk *sdkp)
+{
+	struct scsi_device *sdev = sdkp->device;
+
+	mutex_lock(&sd_ref_mutex);
+	put_device(&sdkp->dev);
+	scsi_device_put(sdev);
+	mutex_unlock(&sd_ref_mutex);
+}
+
+static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
+{
+	unsigned int prot_op = SCSI_PROT_NORMAL;
+	unsigned int dix = scsi_prot_sg_count(scmd);
+
+	if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
+		if (dif && dix)
+			prot_op = SCSI_PROT_READ_PASS;
+		else if (dif && !dix)
+			prot_op = SCSI_PROT_READ_STRIP;
+		else if (!dif && dix)
+			prot_op = SCSI_PROT_READ_INSERT;
+	} else {
+		if (dif && dix)
+			prot_op = SCSI_PROT_WRITE_PASS;
+		else if (dif && !dix)
+			prot_op = SCSI_PROT_WRITE_INSERT;
+		else if (!dif && dix)
+			prot_op = SCSI_PROT_WRITE_STRIP;
+	}
+
+	scsi_set_prot_op(scmd, prot_op);
+	scsi_set_prot_type(scmd, dif);
+}
+
+static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
+{
+	struct request_queue *q = sdkp->disk->queue;
+	unsigned int logical_block_size = sdkp->device->sector_size;
+	unsigned int max_blocks = 0;
+
+	q->limits.discard_zeroes_data = sdkp->lbprz;
+	q->limits.discard_alignment = sdkp->unmap_alignment *
+		logical_block_size;
+	q->limits.discard_granularity =
+		max(sdkp->physical_block_size,
+		    sdkp->unmap_granularity * logical_block_size);
+
+	sdkp->provisioning_mode = mode;
+
+	switch (mode) {
+
+	case SD_LBP_DISABLE:
+		q->limits.max_discard_sectors = 0;
+		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
+		return;
+
+	case SD_LBP_UNMAP:
+		max_blocks = min_not_zero(sdkp->max_unmap_blocks, 0xffffffff);
+		break;
+
+	case SD_LBP_WS16:
+		max_blocks = min_not_zero(sdkp->max_ws_blocks, 0xffffffff);
+		break;
+
+	case SD_LBP_WS10:
+		max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
+		break;
+
+	case SD_LBP_ZERO:
+		max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
+		q->limits.discard_zeroes_data = 1;
+		break;
+	}
+
+	q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
+	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
+}
+
+/**
+ * scsi_setup_discard_cmnd - unmap blocks on thinly provisioned device
+ * @sdp: scsi device to operate one
+ * @rq: Request to prepare
+ *
+ * Will issue either UNMAP or WRITE SAME(16) depending on preference
+ * indicated by target device.
+ **/
+static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
+{
+	struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
+	struct bio *bio = rq->bio;
+	sector_t sector = bio->bi_sector;
+	unsigned int nr_sectors = bio_sectors(bio);
+	unsigned int len;
+	int ret;
+	char *buf;
+	struct page *page;
+
+	if (sdkp->device->sector_size == 4096) {
+		sector >>= 3;
+		nr_sectors >>= 3;
+	}
+
+	rq->timeout = SD_TIMEOUT;
+
+	memset(rq->cmd, 0, rq->cmd_len);
+
+	page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
+	if (!page)
+		return BLKPREP_DEFER;
+
+	switch (sdkp->provisioning_mode) {
+	case SD_LBP_UNMAP:
+		buf = page_address(page);
+
+		rq->cmd_len = 10;
+		rq->cmd[0] = UNMAP;
+		rq->cmd[8] = 24;
+
+		put_unaligned_be16(6 + 16, &buf[0]);
+		put_unaligned_be16(16, &buf[2]);
+		put_unaligned_be64(sector, &buf[8]);
+		put_unaligned_be32(nr_sectors, &buf[16]);
+
+		len = 24;
+		break;
+
+	case SD_LBP_WS16:
+		rq->cmd_len = 16;
+		rq->cmd[0] = WRITE_SAME_16;
+		rq->cmd[1] = 0x8; /* UNMAP */
+		put_unaligned_be64(sector, &rq->cmd[2]);
+		put_unaligned_be32(nr_sectors, &rq->cmd[10]);
+
+		len = sdkp->device->sector_size;
+		break;
+
+	case SD_LBP_WS10:
+	case SD_LBP_ZERO:
+		rq->cmd_len = 10;
+		rq->cmd[0] = WRITE_SAME;
+		if (sdkp->provisioning_mode == SD_LBP_WS10)
+			rq->cmd[1] = 0x8; /* UNMAP */
+		put_unaligned_be32(sector, &rq->cmd[2]);
+		put_unaligned_be16(nr_sectors, &rq->cmd[7]);
+
+		len = sdkp->device->sector_size;
+		break;
+
+	default:
+		ret = BLKPREP_KILL;
+		goto out;
+	}
+
+	blk_add_request_payload(rq, page, len);
+	ret = scsi_setup_blk_pc_cmnd(sdp, rq);
+	rq->buffer = page_address(page);
+
+out:
+	if (ret != BLKPREP_OK) {
+		__free_page(page);
+		rq->buffer = NULL;
+	}
+	return ret;
+}
+
+static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
+{
+	rq->timeout = SD_FLUSH_TIMEOUT;
+	rq->retries = SD_MAX_RETRIES;
+	rq->cmd[0] = SYNCHRONIZE_CACHE;
+	rq->cmd_len = 10;
+
+	return scsi_setup_blk_pc_cmnd(sdp, rq);
+}
+
+static void sd_unprep_fn(struct request_queue *q, struct request *rq)
+{
+	struct scsi_cmnd *SCpnt = rq->special;
+
+	if (rq->cmd_flags & REQ_DISCARD) {
+		free_page((unsigned long)rq->buffer);
+		rq->buffer = NULL;
+	}
+	if (SCpnt->cmnd != rq->cmd) {
+		mempool_free(SCpnt->cmnd, sd_cdb_pool);
+		SCpnt->cmnd = NULL;
+		SCpnt->cmd_len = 0;
+	}
+}
+
+/**
+ *	sd_prep_fn - build a scsi (read or write) command from
+ *	information in the request structure.
+ *	@SCpnt: pointer to mid-level's per scsi command structure that
+ *	contains request and into which the scsi command is written
+ *
+ *	Returns 1 if successful and 0 if error (or cannot be done now).
+ **/
+static int sd_prep_fn(struct request_queue *q, struct request *rq)
+{
+	struct scsi_cmnd *SCpnt;
+	struct scsi_device *sdp = q->queuedata;
+	struct gendisk *disk = rq->rq_disk;
+	struct scsi_disk *sdkp;
+	sector_t block = blk_rq_pos(rq);
+	sector_t threshold;
+	unsigned int this_count = blk_rq_sectors(rq);
+	int ret, host_dif;
+	unsigned char protect;
+
+	/*
+	 * Discard request come in as REQ_TYPE_FS but we turn them into
+	 * block PC requests to make life easier.
+	 */
+	if (rq->cmd_flags & REQ_DISCARD) {
+		ret = scsi_setup_discard_cmnd(sdp, rq);
+		goto out;
+	} else if (rq->cmd_flags & REQ_FLUSH) {
+		ret = scsi_setup_flush_cmnd(sdp, rq);
+		goto out;
+	} else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
+		ret = scsi_setup_blk_pc_cmnd(sdp, rq);
+		goto out;
+	} else if (rq->cmd_type != REQ_TYPE_FS) {
+		ret = BLKPREP_KILL;
+		goto out;
+	}
+	ret = scsi_setup_fs_cmnd(sdp, rq);
+	if (ret != BLKPREP_OK)
+		goto out;
+	SCpnt = rq->special;
+	sdkp = scsi_disk(disk);
+
+	/* from here on until we're complete, any goto out
+	 * is used for a killable error condition */
+	ret = BLKPREP_KILL;
+
+	SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
+					"sd_prep_fn: block=%llu, "
+					"count=%d\n",
+					(unsigned long long)block,
+					this_count));
+
+	if (!sdp || !scsi_device_online(sdp) ||
+	    block + blk_rq_sectors(rq) > get_capacity(disk)) {
+		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+						"Finishing %u sectors\n",
+						blk_rq_sectors(rq)));
+		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+						"Retry with 0x%p\n", SCpnt));
+		goto out;
+	}
+
+	if (sdp->changed) {
+		/*
+		 * quietly refuse to do anything to a changed disc until 
+		 * the changed bit has been reset
+		 */
+		/* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
+		goto out;
+	}
+
+	/*
+	 * Some SD card readers can't handle multi-sector accesses which touch
+	 * the last one or two hardware sectors.  Split accesses as needed.
+	 */
+	threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
+		(sdp->sector_size / 512);
+
+	if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
+		if (block < threshold) {
+			/* Access up to the threshold but not beyond */
+			this_count = threshold - block;
+		} else {
+			/* Access only a single hardware sector */
+			this_count = sdp->sector_size / 512;
+		}
+	}
+
+	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
+					(unsigned long long)block));
+
+	/*
+	 * If we have a 1K hardware sectorsize, prevent access to single
+	 * 512 byte sectors.  In theory we could handle this - in fact
+	 * the scsi cdrom driver must be able to handle this because
+	 * we typically use 1K blocksizes, and cdroms typically have
+	 * 2K hardware sectorsizes.  Of course, things are simpler
+	 * with the cdrom, since it is read-only.  For performance
+	 * reasons, the filesystems should be able to handle this
+	 * and not force the scsi disk driver to use bounce buffers
+	 * for this.
+	 */
+	if (sdp->sector_size == 1024) {
+		if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
+			scmd_printk(KERN_ERR, SCpnt,
+				    "Bad block number requested\n");
+			goto out;
+		} else {
+			block = block >> 1;
+			this_count = this_count >> 1;
+		}
+	}
+	if (sdp->sector_size == 2048) {
+		if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
+			scmd_printk(KERN_ERR, SCpnt,
+				    "Bad block number requested\n");
+			goto out;
+		} else {
+			block = block >> 2;
+			this_count = this_count >> 2;
+		}
+	}
+	if (sdp->sector_size == 4096) {
+		if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
+			scmd_printk(KERN_ERR, SCpnt,
+				    "Bad block number requested\n");
+			goto out;
+		} else {
+			block = block >> 3;
+			this_count = this_count >> 3;
+		}
+	}
+	if (rq_data_dir(rq) == WRITE) {
+		if (!sdp->writeable) {
+			goto out;
+		}
+		SCpnt->cmnd[0] = WRITE_6;
+		SCpnt->sc_data_direction = DMA_TO_DEVICE;
+
+		if (blk_integrity_rq(rq) &&
+		    sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
+			goto out;
+
+	} else if (rq_data_dir(rq) == READ) {
+		SCpnt->cmnd[0] = READ_6;
+		SCpnt->sc_data_direction = DMA_FROM_DEVICE;
+	} else {
+		scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
+		goto out;
+	}
+
+	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
+					"%s %d/%u 512 byte blocks.\n",
+					(rq_data_dir(rq) == WRITE) ?
+					"writing" : "reading", this_count,
+					blk_rq_sectors(rq)));
+
+	/* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
+	host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
+	if (host_dif)
+		protect = 1 << 5;
+	else
+		protect = 0;
+
+	if (host_dif == SD_DIF_TYPE2_PROTECTION) {
+		SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
+
+		if (unlikely(SCpnt->cmnd == NULL)) {
+			ret = BLKPREP_DEFER;
+			goto out;
+		}
+
+		SCpnt->cmd_len = SD_EXT_CDB_SIZE;
+		memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
+		SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
+		SCpnt->cmnd[7] = 0x18;
+		SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
+		SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
+
+		/* LBA */
+		SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
+		SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
+		SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
+		SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
+		SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
+		SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
+		SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
+		SCpnt->cmnd[19] = (unsigned char) block & 0xff;
+
+		/* Expected Indirect LBA */
+		SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
+		SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
+		SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
+		SCpnt->cmnd[23] = (unsigned char) block & 0xff;
+
+		/* Transfer length */
+		SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
+		SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
+		SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
+		SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
+	} else if (block > 0xffffffff) {
+		SCpnt->cmnd[0] += READ_16 - READ_6;
+		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
+		SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
+		SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
+		SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
+		SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
+		SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
+		SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
+		SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
+		SCpnt->cmnd[9] = (unsigned char) block & 0xff;
+		SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
+		SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
+		SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
+		SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
+		SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
+	} else if ((this_count > 0xff) || (block > 0x1fffff) ||
+		   scsi_device_protection(SCpnt->device) ||
+		   SCpnt->device->use_10_for_rw) {
+		if (this_count > 0xffff)
+			this_count = 0xffff;
+
+		SCpnt->cmnd[0] += READ_10 - READ_6;
+		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
+		SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
+		SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
+		SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
+		SCpnt->cmnd[5] = (unsigned char) block & 0xff;
+		SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
+		SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
+		SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
+	} else {
+		if (unlikely(rq->cmd_flags & REQ_FUA)) {
+			/*
+			 * This happens only if this drive failed
+			 * 10byte rw command with ILLEGAL_REQUEST
+			 * during operation and thus turned off
+			 * use_10_for_rw.
+			 */
+			scmd_printk(KERN_ERR, SCpnt,
+				    "FUA write on READ/WRITE(6) drive\n");
+			goto out;
+		}
+
+		SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
+		SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
+		SCpnt->cmnd[3] = (unsigned char) block & 0xff;
+		SCpnt->cmnd[4] = (unsigned char) this_count;
+		SCpnt->cmnd[5] = 0;
+	}
+	SCpnt->sdb.length = this_count * sdp->sector_size;
+
+	/* If DIF or DIX is enabled, tell HBA how to handle request */
+	if (host_dif || scsi_prot_sg_count(SCpnt))
+		sd_prot_op(SCpnt, host_dif);
+
+	/*
+	 * We shouldn't disconnect in the middle of a sector, so with a dumb
+	 * host adapter, it's safe to assume that we can at least transfer
+	 * this many bytes between each connect / disconnect.
+	 */
+	SCpnt->transfersize = sdp->sector_size;
+	SCpnt->underflow = this_count << 9;
+	SCpnt->allowed = SD_MAX_RETRIES;
+
+	/*
+	 * This indicates that the command is ready from our end to be
+	 * queued.
+	 */
+	ret = BLKPREP_OK;
+ out:
+	return scsi_prep_return(q, rq, ret);
+}
+
+/**
+ *	sd_open - open a scsi disk device
+ *	@inode: only i_rdev member may be used
+ *	@filp: only f_mode and f_flags may be used
+ *
+ *	Returns 0 if successful. Returns a negated errno value in case 
+ *	of error.
+ *
+ *	Note: This can be called from a user context (e.g. fsck(1) )
+ *	or from within the kernel (e.g. as a result of a mount(1) ).
+ *	In the latter case @inode and @filp carry an abridged amount
+ *	of information as noted above.
+ *
+ *	Locking: called with bdev->bd_mutex held.
+ **/
+static int sd_open(struct block_device *bdev, fmode_t mode)
+{
+	struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
+	struct scsi_device *sdev;
+	int retval;
+
+	if (!sdkp)
+		return -ENXIO;
+
+	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
+
+	sdev = sdkp->device;
+
+	retval = scsi_autopm_get_device(sdev);
+	if (retval)
+		goto error_autopm;
+
+	/*
+	 * If the device is in error recovery, wait until it is done.
+	 * If the device is offline, then disallow any access to it.
+	 */
+	retval = -ENXIO;
+	if (!scsi_block_when_processing_errors(sdev))
+		goto error_out;
+
+	if (sdev->removable || sdkp->write_prot)
+		check_disk_change(bdev);
+
+	/*
+	 * If the drive is empty, just let the open fail.
+	 */
+	retval = -ENOMEDIUM;
+	if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
+		goto error_out;
+
+	/*
+	 * If the device has the write protect tab set, have the open fail
+	 * if the user expects to be able to write to the thing.
+	 */
+	retval = -EROFS;
+	if (sdkp->write_prot && (mode & FMODE_WRITE))
+		goto error_out;
+
+	/*
+	 * It is possible that the disk changing stuff resulted in
+	 * the device being taken offline.  If this is the case,
+	 * report this to the user, and don't pretend that the
+	 * open actually succeeded.
+	 */
+	retval = -ENXIO;
+	if (!scsi_device_online(sdev))
+		goto error_out;
+
+	if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
+		if (scsi_block_when_processing_errors(sdev))
+			scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
+	}
+
+	return 0;
+
+error_out:
+	scsi_autopm_put_device(sdev);
+error_autopm:
+	scsi_disk_put(sdkp);
+	return retval;	
+}
+
+/**
+ *	sd_release - invoked when the (last) close(2) is called on this
+ *	scsi disk.
+ *	@inode: only i_rdev member may be used
+ *	@filp: only f_mode and f_flags may be used
+ *
+ *	Returns 0. 
+ *
+ *	Note: may block (uninterruptible) if error recovery is underway
+ *	on this disk.
+ *
+ *	Locking: called with bdev->bd_mutex held.
+ **/
+static int sd_release(struct gendisk *disk, fmode_t mode)
+{
+	struct scsi_disk *sdkp = scsi_disk(disk);
+	struct scsi_device *sdev = sdkp->device;
+
+	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
+
+	if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
+		if (scsi_block_when_processing_errors(sdev))
+			scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
+	}
+
+	/*
+	 * XXX and what if there are packets in flight and this close()
+	 * XXX is followed by a "rmmod sd_mod"?
+	 */
+
+	scsi_autopm_put_device(sdev);
+	scsi_disk_put(sdkp);
+	return 0;
+}
+
+static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
+	struct scsi_device *sdp = sdkp->device;
+	struct Scsi_Host *host = sdp->host;
+	int diskinfo[4];
+
+	/* default to most commonly used values */
+        diskinfo[0] = 0x40;	/* 1 << 6 */
+       	diskinfo[1] = 0x20;	/* 1 << 5 */
+       	diskinfo[2] = sdkp->capacity >> 11;
+	
+	/* override with calculated, extended default, or driver values */
+	if (host->hostt->bios_param)
+		host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
+	else
+		scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
+
+	geo->heads = diskinfo[0];
+	geo->sectors = diskinfo[1];
+	geo->cylinders = diskinfo[2];
+	return 0;
+}
+
+/**
+ *	sd_ioctl - process an ioctl
+ *	@inode: only i_rdev/i_bdev members may be used
+ *	@filp: only f_mode and f_flags may be used
+ *	@cmd: ioctl command number
+ *	@arg: this is third argument given to ioctl(2) system call.
+ *	Often contains a pointer.
+ *
+ *	Returns 0 if successful (some ioctls return positive numbers on
+ *	success as well). Returns a negated errno value in case of error.
+ *
+ *	Note: most ioctls are forward onto the block subsystem or further
+ *	down in the scsi subsystem.
+ **/
+static int sd_ioctl(struct block_device *bdev, fmode_t mode,
+		    unsigned int cmd, unsigned long arg)
+{
+	struct gendisk *disk = bdev->bd_disk;
+	struct scsi_disk *sdkp = scsi_disk(disk);
+	struct scsi_device *sdp = sdkp->device;
+	void __user *p = (void __user *)arg;
+	int error;
+    
+	SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
+				    "cmd=0x%x\n", disk->disk_name, cmd));
+
+	error = scsi_verify_blk_ioctl(bdev, cmd);
+	if (error < 0)
+		return error;
+
+	/*
+	 * If we are in the middle of error recovery, don't let anyone
+	 * else try and use this device.  Also, if error recovery fails, it
+	 * may try and take the device offline, in which case all further
+	 * access to the device is prohibited.
+	 */
+	error = scsi_nonblockable_ioctl(sdp, cmd, p,
+					(mode & FMODE_NDELAY) != 0);
+	if (!scsi_block_when_processing_errors(sdp) || !error)
+		goto out;
+
+	/*
+	 * Send SCSI addressing ioctls directly to mid level, send other
+	 * ioctls to block level and then onto mid level if they can't be
+	 * resolved.
+	 */
+	switch (cmd) {
+		case SCSI_IOCTL_GET_IDLUN:
+		case SCSI_IOCTL_GET_BUS_NUMBER:
+			error = scsi_ioctl(sdp, cmd, p);
+			break;
+		default:
+			error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
+			if (error != -ENOTTY)
+				break;
+			error = scsi_ioctl(sdp, cmd, p);
+			break;
+	}
+out:
+	return error;
+}
+
+static void set_media_not_present(struct scsi_disk *sdkp)
+{
+	if (sdkp->media_present)
+		sdkp->device->changed = 1;
+
+	if (sdkp->device->removable) {
+		sdkp->media_present = 0;
+		sdkp->capacity = 0;
+	}
+}
+
+static int media_not_present(struct scsi_disk *sdkp,
+			     struct scsi_sense_hdr *sshdr)
+{
+	if (!scsi_sense_valid(sshdr))
+		return 0;
+
+	/* not invoked for commands that could return deferred errors */
+	switch (sshdr->sense_key) {
+	case UNIT_ATTENTION:
+	case NOT_READY:
+		/* medium not present */
+		if (sshdr->asc == 0x3A) {
+			set_media_not_present(sdkp);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/**
+ *	sd_check_events - check media events
+ *	@disk: kernel device descriptor
+ *	@clearing: disk events currently being cleared
+ *
+ *	Returns mask of DISK_EVENT_*.
+ *
+ *	Note: this function is invoked from the block subsystem.
+ **/
+static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
+{
+	struct scsi_disk *sdkp = scsi_disk(disk);
+	struct scsi_device *sdp = sdkp->device;
+	struct scsi_sense_hdr *sshdr = NULL;
+	int retval;
+
+	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
+
+	/*
+	 * If the device is offline, don't send any commands - just pretend as
+	 * if the command failed.  If the device ever comes back online, we
+	 * can deal with it then.  It is only because of unrecoverable errors
+	 * that we would ever take a device offline in the first place.
+	 */
+	if (!scsi_device_online(sdp)) {
+		set_media_not_present(sdkp);
+		goto out;
+	}
+
+	/*
+	 * Using TEST_UNIT_READY enables differentiation between drive with
+	 * no cartridge loaded - NOT READY, drive with changed cartridge -
+	 * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
+	 *
+	 * Drives that auto spin down. eg iomega jaz 1G, will be started
+	 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
+	 * sd_revalidate() is called.
+	 */
+	retval = -ENODEV;
+
+	if (scsi_block_when_processing_errors(sdp)) {
+		retval = scsi_autopm_get_device(sdp);
+		if (retval)
+			goto out;
+
+		sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
+		retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
+					      sshdr);
+		scsi_autopm_put_device(sdp);
+	}
+
+	/* failed to execute TUR, assume media not present */
+	if (host_byte(retval)) {
+		set_media_not_present(sdkp);
+		goto out;
+	}
+
+	if (media_not_present(sdkp, sshdr))
+		goto out;
+
+	/*
+	 * For removable scsi disk we have to recognise the presence
+	 * of a disk in the drive.
+	 */
+	if (!sdkp->media_present)
+		sdp->changed = 1;
+	sdkp->media_present = 1;
+out:
+	/*
+	 * sdp->changed is set under the following conditions:
+	 *
+	 *	Medium present state has changed in either direction.
+	 *	Device has indicated UNIT_ATTENTION.
+	 */
+	kfree(sshdr);
+	retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
+	sdp->changed = 0;
+	return retval;
+}
+
+static int sd_sync_cache(struct scsi_disk *sdkp)
+{
+	int retries, res;
+	struct scsi_device *sdp = sdkp->device;
+	struct scsi_sense_hdr sshdr;
+
+	if (!scsi_device_online(sdp))
+		return -ENODEV;
+
+
+	for (retries = 3; retries > 0; --retries) {
+		unsigned char cmd[10] = { 0 };
+
+		cmd[0] = SYNCHRONIZE_CACHE;
+		/*
+		 * Leave the rest of the command zero to indicate
+		 * flush everything.
+		 */
+		res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
+				       SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
+		if (res == 0)
+			break;
+	}
+
+	if (res) {
+		sd_print_result(sdkp, res);
+		if (driver_byte(res) & DRIVER_SENSE)
+			sd_print_sense_hdr(sdkp, &sshdr);
+	}
+
+	if (res)
+		return -EIO;
+	return 0;
+}
+
+static void sd_rescan(struct device *dev)
+{
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+
+	if (sdkp) {
+		revalidate_disk(sdkp->disk);
+		scsi_disk_put(sdkp);
+	}
+}
+
+
+#ifdef CONFIG_COMPAT
+/* 
+ * This gets directly called from VFS. When the ioctl 
+ * is not recognized we go back to the other translation paths. 
+ */
+static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
+			   unsigned int cmd, unsigned long arg)
+{
+	struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
+	int ret;
+
+	ret = scsi_verify_blk_ioctl(bdev, cmd);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * If we are in the middle of error recovery, don't let anyone
+	 * else try and use this device.  Also, if error recovery fails, it
+	 * may try and take the device offline, in which case all further
+	 * access to the device is prohibited.
+	 */
+	if (!scsi_block_when_processing_errors(sdev))
+		return -ENODEV;
+	       
+	if (sdev->host->hostt->compat_ioctl) {
+		ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
+
+		return ret;
+	}
+
+	/* 
+	 * Let the static ioctl translation table take care of it.
+	 */
+	return -ENOIOCTLCMD; 
+}
+#endif
+
+static const struct block_device_operations sd_fops = {
+	.owner			= THIS_MODULE,
+	.open			= sd_open,
+	.release		= sd_release,
+	.ioctl			= sd_ioctl,
+	.getgeo			= sd_getgeo,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= sd_compat_ioctl,
+#endif
+	.check_events		= sd_check_events,
+	.revalidate_disk	= sd_revalidate_disk,
+	.unlock_native_capacity	= sd_unlock_native_capacity,
+};
+
+/**
+ *	sd_eh_action - error handling callback
+ *	@scmd:		sd-issued command that has failed
+ *	@eh_cmnd:	The command that was sent during error handling
+ *	@eh_cmnd_len:	Length of eh_cmnd in bytes
+ *	@eh_disp:	The recovery disposition suggested by the midlayer
+ *
+ *	This function is called by the SCSI midlayer upon completion of
+ *	an error handling command (TEST UNIT READY, START STOP UNIT,
+ *	etc.) The command sent to the device by the error handler is
+ *	stored in eh_cmnd. The result of sending the eh command is
+ *	passed in eh_disp.
+ **/
+static int sd_eh_action(struct scsi_cmnd *scmd, unsigned char *eh_cmnd,
+			int eh_cmnd_len, int eh_disp)
+{
+	struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk);
+
+	if (!scsi_device_online(scmd->device) ||
+	    !scsi_medium_access_command(scmd))
+		return eh_disp;
+
+	/*
+	 * The device has timed out executing a medium access command.
+	 * However, the TEST UNIT READY command sent during error
+	 * handling completed successfully. Either the device is in the
+	 * process of recovering or has it suffered an internal failure
+	 * that prevents access to the storage medium.
+	 */
+	if (host_byte(scmd->result) == DID_TIME_OUT && eh_disp == SUCCESS &&
+	    eh_cmnd_len && eh_cmnd[0] == TEST_UNIT_READY)
+		sdkp->medium_access_timed_out++;
+
+	/*
+	 * If the device keeps failing read/write commands but TEST UNIT
+	 * READY always completes successfully we assume that medium
+	 * access is no longer possible and take the device offline.
+	 */
+	if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) {
+		scmd_printk(KERN_ERR, scmd,
+			    "Medium access timeout failure. Offlining disk!\n");
+		scsi_device_set_state(scmd->device, SDEV_OFFLINE);
+
+		return FAILED;
+	}
+
+	return eh_disp;
+}
+
+static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
+{
+	u64 start_lba = blk_rq_pos(scmd->request);
+	u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
+	u64 factor = scmd->device->sector_size / 512;
+	u64 bad_lba;
+	int info_valid;
+	/*
+	 * resid is optional but mostly filled in.  When it's unused,
+	 * its value is zero, so we assume the whole buffer transferred
+	 */
+	unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
+	unsigned int good_bytes;
+
+	if (scmd->request->cmd_type != REQ_TYPE_FS)
+		return 0;
+
+	info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
+					     SCSI_SENSE_BUFFERSIZE,
+					     &bad_lba);
+	if (!info_valid)
+		return 0;
+
+	if (scsi_bufflen(scmd) <= scmd->device->sector_size)
+		return 0;
+
+	/* be careful ... don't want any overflows */
+	factor = scmd->device->sector_size / 512;
+	do_div(start_lba, factor);
+	do_div(end_lba, factor);
+
+	/* The bad lba was reported incorrectly, we have no idea where
+	 * the error is.
+	 */
+	if (bad_lba < start_lba  || bad_lba >= end_lba)
+		return 0;
+
+	/* This computation should always be done in terms of
+	 * the resolution of the device's medium.
+	 */
+	good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
+	return min(good_bytes, transferred);
+}
+
+/**
+ *	sd_done - bottom half handler: called when the lower level
+ *	driver has completed (successfully or otherwise) a scsi command.
+ *	@SCpnt: mid-level's per command structure.
+ *
+ *	Note: potentially run from within an ISR. Must not block.
+ **/
+static int sd_done(struct scsi_cmnd *SCpnt)
+{
+	int result = SCpnt->result;
+	unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
+	struct scsi_sense_hdr sshdr;
+	struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
+	int sense_valid = 0;
+	int sense_deferred = 0;
+	unsigned char op = SCpnt->cmnd[0];
+
+	if ((SCpnt->request->cmd_flags & REQ_DISCARD) && !result)
+		scsi_set_resid(SCpnt, 0);
+
+	if (result) {
+		sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
+		if (sense_valid)
+			sense_deferred = scsi_sense_is_deferred(&sshdr);
+	}
+#ifdef CONFIG_SCSI_LOGGING
+	SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
+	if (sense_valid) {
+		SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
+						   "sd_done: sb[respc,sk,asc,"
+						   "ascq]=%x,%x,%x,%x\n",
+						   sshdr.response_code,
+						   sshdr.sense_key, sshdr.asc,
+						   sshdr.ascq));
+	}
+#endif
+	if (driver_byte(result) != DRIVER_SENSE &&
+	    (!sense_valid || sense_deferred))
+		goto out;
+
+	sdkp->medium_access_timed_out = 0;
+
+	switch (sshdr.sense_key) {
+	case HARDWARE_ERROR:
+	case MEDIUM_ERROR:
+		good_bytes = sd_completed_bytes(SCpnt);
+		break;
+	case RECOVERED_ERROR:
+		good_bytes = scsi_bufflen(SCpnt);
+		break;
+	case NO_SENSE:
+		/* This indicates a false check condition, so ignore it.  An
+		 * unknown amount of data was transferred so treat it as an
+		 * error.
+		 */
+		scsi_print_sense("sd", SCpnt);
+		SCpnt->result = 0;
+		memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
+		break;
+	case ABORTED_COMMAND:
+		if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
+			good_bytes = sd_completed_bytes(SCpnt);
+		break;
+	case ILLEGAL_REQUEST:
+		if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
+			good_bytes = sd_completed_bytes(SCpnt);
+		/* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
+		if ((sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
+		    (op == UNMAP || op == WRITE_SAME_16 || op == WRITE_SAME))
+			sd_config_discard(sdkp, SD_LBP_DISABLE);
+		break;
+	default:
+		break;
+	}
+ out:
+	if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
+		sd_dif_complete(SCpnt, good_bytes);
+
+	return good_bytes;
+}
+
+/*
+ * spinup disk - called only in sd_revalidate_disk()
+ */
+static void
+sd_spinup_disk(struct scsi_disk *sdkp)
+{
+	unsigned char cmd[10];
+	unsigned long spintime_expire = 0;
+	int retries, spintime;
+	unsigned int the_result;
+	struct scsi_sense_hdr sshdr;
+	int sense_valid = 0;
+
+	spintime = 0;
+
+	/* Spin up drives, as required.  Only do this at boot time */
+	/* Spinup needs to be done for module loads too. */
+	do {
+		retries = 0;
+
+		do {
+			cmd[0] = TEST_UNIT_READY;
+			memset((void *) &cmd[1], 0, 9);
+
+			the_result = scsi_execute_req(sdkp->device, cmd,
+						      DMA_NONE, NULL, 0,
+						      &sshdr, SD_TIMEOUT,
+						      SD_MAX_RETRIES, NULL);
+
+			/*
+			 * If the drive has indicated to us that it
+			 * doesn't have any media in it, don't bother
+			 * with any more polling.
+			 */
+			if (media_not_present(sdkp, &sshdr))
+				return;
+
+			if (the_result)
+				sense_valid = scsi_sense_valid(&sshdr);
+			retries++;
+		} while (retries < 3 && 
+			 (!scsi_status_is_good(the_result) ||
+			  ((driver_byte(the_result) & DRIVER_SENSE) &&
+			  sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
+
+		if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
+			/* no sense, TUR either succeeded or failed
+			 * with a status error */
+			if(!spintime && !scsi_status_is_good(the_result)) {
+				sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
+				sd_print_result(sdkp, the_result);
+			}
+			break;
+		}
+					
+		/*
+		 * The device does not want the automatic start to be issued.
+		 */
+		if (sdkp->device->no_start_on_add)
+			break;
+
+		if (sense_valid && sshdr.sense_key == NOT_READY) {
+			if (sshdr.asc == 4 && sshdr.ascq == 3)
+				break;	/* manual intervention required */
+			if (sshdr.asc == 4 && sshdr.ascq == 0xb)
+				break;	/* standby */
+			if (sshdr.asc == 4 && sshdr.ascq == 0xc)
+				break;	/* unavailable */
+			/*
+			 * Issue command to spin up drive when not ready
+			 */
+			if (!spintime) {
+				sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
+				cmd[0] = START_STOP;
+				cmd[1] = 1;	/* Return immediately */
+				memset((void *) &cmd[2], 0, 8);
+				cmd[4] = 1;	/* Start spin cycle */
+				if (sdkp->device->start_stop_pwr_cond)
+					cmd[4] |= 1 << 4;
+				scsi_execute_req(sdkp->device, cmd, DMA_NONE,
+						 NULL, 0, &sshdr,
+						 SD_TIMEOUT, SD_MAX_RETRIES,
+						 NULL);
+				spintime_expire = jiffies + 100 * HZ;
+				spintime = 1;
+			}
+			/* Wait 1 second for next try */
+			msleep(1000);
+			printk(".");
+
+		/*
+		 * Wait for USB flash devices with slow firmware.
+		 * Yes, this sense key/ASC combination shouldn't
+		 * occur here.  It's characteristic of these devices.
+		 */
+		} else if (sense_valid &&
+				sshdr.sense_key == UNIT_ATTENTION &&
+				sshdr.asc == 0x28) {
+			if (!spintime) {
+				spintime_expire = jiffies + 5 * HZ;
+				spintime = 1;
+			}
+			/* Wait 1 second for next try */
+			msleep(1000);
+		} else {
+			/* we don't understand the sense code, so it's
+			 * probably pointless to loop */
+			if(!spintime) {
+				sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
+				sd_print_sense_hdr(sdkp, &sshdr);
+			}
+			break;
+		}
+				
+	} while (spintime && time_before_eq(jiffies, spintime_expire));
+
+	if (spintime) {
+		if (scsi_status_is_good(the_result))
+			printk("ready\n");
+		else
+			printk("not responding...\n");
+	}
+}
+
+
+/*
+ * Determine whether disk supports Data Integrity Field.
+ */
+static void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	struct scsi_device *sdp = sdkp->device;
+	u8 type;
+
+	if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
+		return;
+
+	type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
+
+	if (type == sdkp->protection_type || !sdkp->first_scan)
+		return;
+
+	sdkp->protection_type = type;
+
+	if (type > SD_DIF_TYPE3_PROTECTION) {
+		sd_printk(KERN_ERR, sdkp, "formatted with unsupported "	\
+			  "protection type %u. Disabling disk!\n", type);
+		sdkp->capacity = 0;
+		return;
+	}
+
+	if (scsi_host_dif_capable(sdp->host, type))
+		sd_printk(KERN_NOTICE, sdkp,
+			  "Enabling DIF Type %u protection\n", type);
+	else
+		sd_printk(KERN_NOTICE, sdkp,
+			  "Disabling DIF Type %u protection\n", type);
+}
+
+static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
+			struct scsi_sense_hdr *sshdr, int sense_valid,
+			int the_result)
+{
+	sd_print_result(sdkp, the_result);
+	if (driver_byte(the_result) & DRIVER_SENSE)
+		sd_print_sense_hdr(sdkp, sshdr);
+	else
+		sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
+
+	/*
+	 * Set dirty bit for removable devices if not ready -
+	 * sometimes drives will not report this properly.
+	 */
+	if (sdp->removable &&
+	    sense_valid && sshdr->sense_key == NOT_READY)
+		set_media_not_present(sdkp);
+
+	/*
+	 * We used to set media_present to 0 here to indicate no media
+	 * in the drive, but some drives fail read capacity even with
+	 * media present, so we can't do that.
+	 */
+	sdkp->capacity = 0; /* unknown mapped to zero - as usual */
+}
+
+#define RC16_LEN 32
+#if RC16_LEN > SD_BUF_SIZE
+#error RC16_LEN must not be more than SD_BUF_SIZE
+#endif
+
+#define READ_CAPACITY_RETRIES_ON_RESET	10
+
+static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
+						unsigned char *buffer)
+{
+	unsigned char cmd[16];
+	struct scsi_sense_hdr sshdr;
+	int sense_valid = 0;
+	int the_result;
+	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
+	unsigned int alignment;
+	unsigned long long lba;
+	unsigned sector_size;
+
+	if (sdp->no_read_capacity_16)
+		return -EINVAL;
+
+	do {
+		memset(cmd, 0, 16);
+		cmd[0] = SERVICE_ACTION_IN;
+		cmd[1] = SAI_READ_CAPACITY_16;
+		cmd[13] = RC16_LEN;
+		memset(buffer, 0, RC16_LEN);
+
+		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
+					buffer, RC16_LEN, &sshdr,
+					SD_TIMEOUT, SD_MAX_RETRIES, NULL);
+
+		if (media_not_present(sdkp, &sshdr))
+			return -ENODEV;
+
+		if (the_result) {
+			sense_valid = scsi_sense_valid(&sshdr);
+			if (sense_valid &&
+			    sshdr.sense_key == ILLEGAL_REQUEST &&
+			    (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
+			    sshdr.ascq == 0x00)
+				/* Invalid Command Operation Code or
+				 * Invalid Field in CDB, just retry
+				 * silently with RC10 */
+				return -EINVAL;
+			if (sense_valid &&
+			    sshdr.sense_key == UNIT_ATTENTION &&
+			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
+				/* Device reset might occur several times,
+				 * give it one more chance */
+				if (--reset_retries > 0)
+					continue;
+		}
+		retries--;
+
+	} while (the_result && retries);
+
+	if (the_result) {
+		sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
+		read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
+		return -EINVAL;
+	}
+
+	sector_size = get_unaligned_be32(&buffer[8]);
+	lba = get_unaligned_be64(&buffer[0]);
+
+	sd_read_protection_type(sdkp, buffer);
+
+	if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
+		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
+			"kernel compiled with support for large block "
+			"devices.\n");
+		sdkp->capacity = 0;
+		return -EOVERFLOW;
+	}
+
+	/* Logical blocks per physical block exponent */
+	sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
+
+	/* Lowest aligned logical block */
+	alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
+	blk_queue_alignment_offset(sdp->request_queue, alignment);
+	if (alignment && sdkp->first_scan)
+		sd_printk(KERN_NOTICE, sdkp,
+			  "physical block alignment offset: %u\n", alignment);
+
+	if (buffer[14] & 0x80) { /* LBPME */
+		sdkp->lbpme = 1;
+
+		if (buffer[14] & 0x40) /* LBPRZ */
+			sdkp->lbprz = 1;
+
+		sd_config_discard(sdkp, SD_LBP_WS16);
+	}
+
+	sdkp->capacity = lba + 1;
+	return sector_size;
+}
+
+static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
+						unsigned char *buffer)
+{
+	unsigned char cmd[16];
+	struct scsi_sense_hdr sshdr;
+	int sense_valid = 0;
+	int the_result;
+	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
+	sector_t lba;
+	unsigned sector_size;
+
+	do {
+		cmd[0] = READ_CAPACITY;
+		memset(&cmd[1], 0, 9);
+		memset(buffer, 0, 8);
+
+		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
+					buffer, 8, &sshdr,
+					SD_TIMEOUT, SD_MAX_RETRIES, NULL);
+
+		if (media_not_present(sdkp, &sshdr))
+			return -ENODEV;
+
+		if (the_result) {
+			sense_valid = scsi_sense_valid(&sshdr);
+			if (sense_valid &&
+			    sshdr.sense_key == UNIT_ATTENTION &&
+			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
+				/* Device reset might occur several times,
+				 * give it one more chance */
+				if (--reset_retries > 0)
+					continue;
+		}
+		retries--;
+
+	} while (the_result && retries);
+
+	if (the_result) {
+		sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
+		read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
+		return -EINVAL;
+	}
+
+	sector_size = get_unaligned_be32(&buffer[4]);
+	lba = get_unaligned_be32(&buffer[0]);
+
+	if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
+		/* Some buggy (usb cardreader) devices return an lba of
+		   0xffffffff when the want to report a size of 0 (with
+		   which they really mean no media is present) */
+		sdkp->capacity = 0;
+		sdkp->physical_block_size = sector_size;
+		return sector_size;
+	}
+
+	if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
+		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
+			"kernel compiled with support for large block "
+			"devices.\n");
+		sdkp->capacity = 0;
+		return -EOVERFLOW;
+	}
+
+	sdkp->capacity = lba + 1;
+	sdkp->physical_block_size = sector_size;
+	return sector_size;
+}
+
+static int sd_try_rc16_first(struct scsi_device *sdp)
+{
+	if (sdp->host->max_cmd_len < 16)
+		return 0;
+	if (sdp->try_rc_10_first)
+		return 0;
+	if (sdp->scsi_level > SCSI_SPC_2)
+		return 1;
+	if (scsi_device_protection(sdp))
+		return 1;
+	return 0;
+}
+
+/*
+ * read disk capacity
+ */
+static void
+sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	int sector_size;
+	struct scsi_device *sdp = sdkp->device;
+	sector_t old_capacity = sdkp->capacity;
+
+	if (sd_try_rc16_first(sdp)) {
+		sector_size = read_capacity_16(sdkp, sdp, buffer);
+		if (sector_size == -EOVERFLOW)
+			goto got_data;
+		if (sector_size == -ENODEV)
+			return;
+		if (sector_size < 0)
+			sector_size = read_capacity_10(sdkp, sdp, buffer);
+		if (sector_size < 0)
+			return;
+	} else {
+		sector_size = read_capacity_10(sdkp, sdp, buffer);
+		if (sector_size == -EOVERFLOW)
+			goto got_data;
+		if (sector_size < 0)
+			return;
+		if ((sizeof(sdkp->capacity) > 4) &&
+		    (sdkp->capacity > 0xffffffffULL)) {
+			int old_sector_size = sector_size;
+			sd_printk(KERN_NOTICE, sdkp, "Very big device. "
+					"Trying to use READ CAPACITY(16).\n");
+			sector_size = read_capacity_16(sdkp, sdp, buffer);
+			if (sector_size < 0) {
+				sd_printk(KERN_NOTICE, sdkp,
+					"Using 0xffffffff as device size\n");
+				sdkp->capacity = 1 + (sector_t) 0xffffffff;
+				sector_size = old_sector_size;
+				goto got_data;
+			}
+		}
+	}
+
+	/* Some devices are known to return the total number of blocks,
+	 * not the highest block number.  Some devices have versions
+	 * which do this and others which do not.  Some devices we might
+	 * suspect of doing this but we don't know for certain.
+	 *
+	 * If we know the reported capacity is wrong, decrement it.  If
+	 * we can only guess, then assume the number of blocks is even
+	 * (usually true but not always) and err on the side of lowering
+	 * the capacity.
+	 */
+	if (sdp->fix_capacity ||
+	    (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
+		sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
+				"from its reported value: %llu\n",
+				(unsigned long long) sdkp->capacity);
+		--sdkp->capacity;
+	}
+
+got_data:
+	if (sector_size == 0) {
+		sector_size = 512;
+		sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
+			  "assuming 512.\n");
+	}
+
+	if (sector_size != 512 &&
+	    sector_size != 1024 &&
+	    sector_size != 2048 &&
+	    sector_size != 4096) {
+		sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
+			  sector_size);
+		/*
+		 * The user might want to re-format the drive with
+		 * a supported sectorsize.  Once this happens, it
+		 * would be relatively trivial to set the thing up.
+		 * For this reason, we leave the thing in the table.
+		 */
+		sdkp->capacity = 0;
+		/*
+		 * set a bogus sector size so the normal read/write
+		 * logic in the block layer will eventually refuse any
+		 * request on this device without tripping over power
+		 * of two sector size assumptions
+		 */
+		sector_size = 512;
+	}
+	blk_queue_logical_block_size(sdp->request_queue, sector_size);
+
+	{
+		char cap_str_2[10], cap_str_10[10];
+		u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
+
+		string_get_size(sz, STRING_UNITS_2, cap_str_2,
+				sizeof(cap_str_2));
+		string_get_size(sz, STRING_UNITS_10, cap_str_10,
+				sizeof(cap_str_10));
+
+		if (sdkp->first_scan || old_capacity != sdkp->capacity) {
+			sd_printk(KERN_NOTICE, sdkp,
+				  "%llu %d-byte logical blocks: (%s/%s)\n",
+				  (unsigned long long)sdkp->capacity,
+				  sector_size, cap_str_10, cap_str_2);
+
+			if (sdkp->physical_block_size != sector_size)
+				sd_printk(KERN_NOTICE, sdkp,
+					  "%u-byte physical blocks\n",
+					  sdkp->physical_block_size);
+		}
+	}
+
+	/* Rescale capacity to 512-byte units */
+	if (sector_size == 4096)
+		sdkp->capacity <<= 3;
+	else if (sector_size == 2048)
+		sdkp->capacity <<= 2;
+	else if (sector_size == 1024)
+		sdkp->capacity <<= 1;
+
+	blk_queue_physical_block_size(sdp->request_queue,
+				      sdkp->physical_block_size);
+	sdkp->device->sector_size = sector_size;
+}
+
+/* called with buffer of length 512 */
+static inline int
+sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
+		 unsigned char *buffer, int len, struct scsi_mode_data *data,
+		 struct scsi_sense_hdr *sshdr)
+{
+	return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
+			       SD_TIMEOUT, SD_MAX_RETRIES, data,
+			       sshdr);
+}
+
+/*
+ * read write protect setting, if possible - called only in sd_revalidate_disk()
+ * called with buffer of length SD_BUF_SIZE
+ */
+static void
+sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	int res;
+	struct scsi_device *sdp = sdkp->device;
+	struct scsi_mode_data data;
+	int old_wp = sdkp->write_prot;
+
+	set_disk_ro(sdkp->disk, 0);
+	if (sdp->skip_ms_page_3f) {
+		sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
+		return;
+	}
+
+	if (sdp->use_192_bytes_for_3f) {
+		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
+	} else {
+		/*
+		 * First attempt: ask for all pages (0x3F), but only 4 bytes.
+		 * We have to start carefully: some devices hang if we ask
+		 * for more than is available.
+		 */
+		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
+
+		/*
+		 * Second attempt: ask for page 0 When only page 0 is
+		 * implemented, a request for page 3F may return Sense Key
+		 * 5: Illegal Request, Sense Code 24: Invalid field in
+		 * CDB.
+		 */
+		if (!scsi_status_is_good(res))
+			res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
+
+		/*
+		 * Third attempt: ask 255 bytes, as we did earlier.
+		 */
+		if (!scsi_status_is_good(res))
+			res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
+					       &data, NULL);
+	}
+
+	if (!scsi_status_is_good(res)) {
+		sd_printk(KERN_WARNING, sdkp,
+			  "Test WP failed, assume Write Enabled\n");
+	} else {
+		sdkp->write_prot = ((data.device_specific & 0x80) != 0);
+		set_disk_ro(sdkp->disk, sdkp->write_prot);
+		if (sdkp->first_scan || old_wp != sdkp->write_prot) {
+			sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
+				  sdkp->write_prot ? "on" : "off");
+			sd_printk(KERN_DEBUG, sdkp,
+				  "Mode Sense: %02x %02x %02x %02x\n",
+				  buffer[0], buffer[1], buffer[2], buffer[3]);
+		}
+	}
+}
+
+/*
+ * sd_read_cache_type - called only from sd_revalidate_disk()
+ * called with buffer of length SD_BUF_SIZE
+ */
+static void
+sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	int len = 0, res;
+	struct scsi_device *sdp = sdkp->device;
+
+	int dbd;
+	int modepage;
+	int first_len;
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+	int old_wce = sdkp->WCE;
+	int old_rcd = sdkp->RCD;
+	int old_dpofua = sdkp->DPOFUA;
+
+
+	if (sdkp->cache_override)
+		return;
+
+	first_len = 4;
+	if (sdp->skip_ms_page_8) {
+		if (sdp->type == TYPE_RBC)
+			goto defaults;
+		else {
+			if (sdp->skip_ms_page_3f)
+				goto defaults;
+			modepage = 0x3F;
+			if (sdp->use_192_bytes_for_3f)
+				first_len = 192;
+			dbd = 0;
+		}
+	} else if (sdp->type == TYPE_RBC) {
+		modepage = 6;
+		dbd = 8;
+	} else {
+		modepage = 8;
+		dbd = 0;
+	}
+
+	/* cautiously ask */
+	res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
+			&data, &sshdr);
+
+	if (!scsi_status_is_good(res))
+		goto bad_sense;
+
+	if (!data.header_length) {
+		modepage = 6;
+		first_len = 0;
+		sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
+	}
+
+	/* that went OK, now ask for the proper length */
+	len = data.length;
+
+	/*
+	 * We're only interested in the first three bytes, actually.
+	 * But the data cache page is defined for the first 20.
+	 */
+	if (len < 3)
+		goto bad_sense;
+	else if (len > SD_BUF_SIZE) {
+		sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
+			  "data from %d to %d bytes\n", len, SD_BUF_SIZE);
+		len = SD_BUF_SIZE;
+	}
+	if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
+		len = 192;
+
+	/* Get the data */
+	if (len > first_len)
+		res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
+				&data, &sshdr);
+
+	if (scsi_status_is_good(res)) {
+		int offset = data.header_length + data.block_descriptor_length;
+
+		while (offset < len) {
+			u8 page_code = buffer[offset] & 0x3F;
+			u8 spf       = buffer[offset] & 0x40;
+
+			if (page_code == 8 || page_code == 6) {
+				/* We're interested only in the first 3 bytes.
+				 */
+				if (len - offset <= 2) {
+					sd_printk(KERN_ERR, sdkp, "Incomplete "
+						  "mode parameter data\n");
+					goto defaults;
+				} else {
+					modepage = page_code;
+					goto Page_found;
+				}
+			} else {
+				/* Go to the next page */
+				if (spf && len - offset > 3)
+					offset += 4 + (buffer[offset+2] << 8) +
+						buffer[offset+3];
+				else if (!spf && len - offset > 1)
+					offset += 2 + buffer[offset+1];
+				else {
+					sd_printk(KERN_ERR, sdkp, "Incomplete "
+						  "mode parameter data\n");
+					goto defaults;
+				}
+			}
+		}
+
+		sd_printk(KERN_ERR, sdkp, "No Caching mode page found\n");
+		goto defaults;
+
+	Page_found:
+		if (modepage == 8) {
+			sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
+			sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
+		} else {
+			sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
+			sdkp->RCD = 0;
+		}
+
+		sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
+		if (sdp->broken_fua) {
+			sd_printk(KERN_NOTICE, sdkp, "Disabling FUA\n");
+			sdkp->DPOFUA = 0;
+		} else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
+			sd_printk(KERN_NOTICE, sdkp,
+				  "Uses READ/WRITE(6), disabling FUA\n");
+			sdkp->DPOFUA = 0;
+		}
+
+		if (sdkp->first_scan || old_wce != sdkp->WCE ||
+		    old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
+			sd_printk(KERN_NOTICE, sdkp,
+				  "Write cache: %s, read cache: %s, %s\n",
+				  sdkp->WCE ? "enabled" : "disabled",
+				  sdkp->RCD ? "disabled" : "enabled",
+				  sdkp->DPOFUA ? "supports DPO and FUA"
+				  : "doesn't support DPO or FUA");
+
+		return;
+	}
+
+bad_sense:
+	if (scsi_sense_valid(&sshdr) &&
+	    sshdr.sense_key == ILLEGAL_REQUEST &&
+	    sshdr.asc == 0x24 && sshdr.ascq == 0x0)
+		/* Invalid field in CDB */
+		sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
+	else
+		sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
+
+defaults:
+	sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
+	sdkp->WCE = 0;
+	sdkp->RCD = 0;
+	sdkp->DPOFUA = 0;
+}
+
+/*
+ * The ATO bit indicates whether the DIF application tag is available
+ * for use by the operating system.
+ */
+static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	int res, offset;
+	struct scsi_device *sdp = sdkp->device;
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+
+	if (sdp->type != TYPE_DISK)
+		return;
+
+	if (sdkp->protection_type == 0)
+		return;
+
+	res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
+			      SD_MAX_RETRIES, &data, &sshdr);
+
+	if (!scsi_status_is_good(res) || !data.header_length ||
+	    data.length < 6) {
+		sd_printk(KERN_WARNING, sdkp,
+			  "getting Control mode page failed, assume no ATO\n");
+
+		if (scsi_sense_valid(&sshdr))
+			sd_print_sense_hdr(sdkp, &sshdr);
+
+		return;
+	}
+
+	offset = data.header_length + data.block_descriptor_length;
+
+	if ((buffer[offset] & 0x3f) != 0x0a) {
+		sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
+		return;
+	}
+
+	if ((buffer[offset + 5] & 0x80) == 0)
+		return;
+
+	sdkp->ATO = 1;
+
+	return;
+}
+
+/**
+ * sd_read_block_limits - Query disk device for preferred I/O sizes.
+ * @disk: disk to query
+ */
+static void sd_read_block_limits(struct scsi_disk *sdkp)
+{
+	unsigned int sector_sz = sdkp->device->sector_size;
+	const int vpd_len = 64;
+	unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
+
+	if (!buffer ||
+	    /* Block Limits VPD */
+	    scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
+		goto out;
+
+	blk_queue_io_min(sdkp->disk->queue,
+			 get_unaligned_be16(&buffer[6]) * sector_sz);
+	blk_queue_io_opt(sdkp->disk->queue,
+			 get_unaligned_be32(&buffer[12]) * sector_sz);
+
+	if (buffer[3] == 0x3c) {
+		unsigned int lba_count, desc_count;
+
+		sdkp->max_ws_blocks =
+			(u32) min_not_zero(get_unaligned_be64(&buffer[36]),
+					   (u64)0xffffffff);
+
+		if (!sdkp->lbpme)
+			goto out;
+
+		lba_count = get_unaligned_be32(&buffer[20]);
+		desc_count = get_unaligned_be32(&buffer[24]);
+
+		if (lba_count && desc_count)
+			sdkp->max_unmap_blocks = lba_count;
+
+		sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
+
+		if (buffer[32] & 0x80)
+			sdkp->unmap_alignment =
+				get_unaligned_be32(&buffer[32]) & ~(1 << 31);
+
+		if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
+
+			if (sdkp->max_unmap_blocks)
+				sd_config_discard(sdkp, SD_LBP_UNMAP);
+			else
+				sd_config_discard(sdkp, SD_LBP_WS16);
+
+		} else {	/* LBP VPD page tells us what to use */
+
+			if (sdkp->lbpu && sdkp->max_unmap_blocks)
+				sd_config_discard(sdkp, SD_LBP_UNMAP);
+			else if (sdkp->lbpws)
+				sd_config_discard(sdkp, SD_LBP_WS16);
+			else if (sdkp->lbpws10)
+				sd_config_discard(sdkp, SD_LBP_WS10);
+			else
+				sd_config_discard(sdkp, SD_LBP_DISABLE);
+		}
+	}
+
+ out:
+	kfree(buffer);
+}
+
+/**
+ * sd_read_block_characteristics - Query block dev. characteristics
+ * @disk: disk to query
+ */
+static void sd_read_block_characteristics(struct scsi_disk *sdkp)
+{
+	unsigned char *buffer;
+	u16 rot;
+	const int vpd_len = 64;
+
+	buffer = kmalloc(vpd_len, GFP_KERNEL);
+
+	if (!buffer ||
+	    /* Block Device Characteristics VPD */
+	    scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
+		goto out;
+
+	rot = get_unaligned_be16(&buffer[4]);
+
+	if (rot == 1)
+		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
+
+ out:
+	kfree(buffer);
+}
+
+/**
+ * sd_read_block_provisioning - Query provisioning VPD page
+ * @disk: disk to query
+ */
+static void sd_read_block_provisioning(struct scsi_disk *sdkp)
+{
+	unsigned char *buffer;
+	const int vpd_len = 8;
+
+	if (sdkp->lbpme == 0)
+		return;
+
+	buffer = kmalloc(vpd_len, GFP_KERNEL);
+
+	if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
+		goto out;
+
+	sdkp->lbpvpd	= 1;
+	sdkp->lbpu	= (buffer[5] >> 7) & 1;	/* UNMAP */
+	sdkp->lbpws	= (buffer[5] >> 6) & 1;	/* WRITE SAME(16) with UNMAP */
+	sdkp->lbpws10	= (buffer[5] >> 5) & 1;	/* WRITE SAME(10) with UNMAP */
+
+ out:
+	kfree(buffer);
+}
+
+static int sd_try_extended_inquiry(struct scsi_device *sdp)
+{
+	/*
+	 * Although VPD inquiries can go to SCSI-2 type devices,
+	 * some USB ones crash on receiving them, and the pages
+	 * we currently ask for are for SPC-3 and beyond
+	 */
+	if (sdp->scsi_level > SCSI_SPC_2 && !sdp->skip_vpd_pages)
+		return 1;
+	return 0;
+}
+
+/**
+ *	sd_revalidate_disk - called the first time a new disk is seen,
+ *	performs disk spin up, read_capacity, etc.
+ *	@disk: struct gendisk we care about
+ **/
+static int sd_revalidate_disk(struct gendisk *disk)
+{
+	struct scsi_disk *sdkp = scsi_disk(disk);
+	struct scsi_device *sdp = sdkp->device;
+	unsigned char *buffer;
+	unsigned flush = 0;
+
+	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
+				      "sd_revalidate_disk\n"));
+
+	/*
+	 * If the device is offline, don't try and read capacity or any
+	 * of the other niceties.
+	 */
+	if (!scsi_device_online(sdp))
+		goto out;
+
+	buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
+	if (!buffer) {
+		sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
+			  "allocation failure.\n");
+		goto out;
+	}
+
+	sd_spinup_disk(sdkp);
+
+	/*
+	 * Without media there is no reason to ask; moreover, some devices
+	 * react badly if we do.
+	 */
+	if (sdkp->media_present) {
+		sd_read_capacity(sdkp, buffer);
+
+		if (sd_try_extended_inquiry(sdp)) {
+			sd_read_block_provisioning(sdkp);
+			sd_read_block_limits(sdkp);
+			sd_read_block_characteristics(sdkp);
+		}
+
+		sd_read_write_protect_flag(sdkp, buffer);
+		sd_read_cache_type(sdkp, buffer);
+		sd_read_app_tag_own(sdkp, buffer);
+	}
+
+	sdkp->first_scan = 0;
+
+	/*
+	 * We now have all cache related info, determine how we deal
+	 * with flush requests.
+	 */
+	if (sdkp->WCE) {
+		flush |= REQ_FLUSH;
+		if (sdkp->DPOFUA)
+			flush |= REQ_FUA;
+	}
+
+	blk_queue_flush(sdkp->disk->queue, flush);
+
+	set_capacity(disk, sdkp->capacity);
+	kfree(buffer);
+
+ out:
+	return 0;
+}
+
+/**
+ *	sd_unlock_native_capacity - unlock native capacity
+ *	@disk: struct gendisk to set capacity for
+ *
+ *	Block layer calls this function if it detects that partitions
+ *	on @disk reach beyond the end of the device.  If the SCSI host
+ *	implements ->unlock_native_capacity() method, it's invoked to
+ *	give it a chance to adjust the device capacity.
+ *
+ *	CONTEXT:
+ *	Defined by block layer.  Might sleep.
+ */
+static void sd_unlock_native_capacity(struct gendisk *disk)
+{
+	struct scsi_device *sdev = scsi_disk(disk)->device;
+
+	if (sdev->host->hostt->unlock_native_capacity)
+		sdev->host->hostt->unlock_native_capacity(sdev);
+}
+
+/**
+ *	sd_format_disk_name - format disk name
+ *	@prefix: name prefix - ie. "sd" for SCSI disks
+ *	@index: index of the disk to format name for
+ *	@buf: output buffer
+ *	@buflen: length of the output buffer
+ *
+ *	SCSI disk names starts at sda.  The 26th device is sdz and the
+ *	27th is sdaa.  The last one for two lettered suffix is sdzz
+ *	which is followed by sdaaa.
+ *
+ *	This is basically 26 base counting with one extra 'nil' entry
+ *	at the beginning from the second digit on and can be
+ *	determined using similar method as 26 base conversion with the
+ *	index shifted -1 after each digit is computed.
+ *
+ *	CONTEXT:
+ *	Don't care.
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
+{
+	const int base = 'z' - 'a' + 1;
+	char *begin = buf + strlen(prefix);
+	char *end = buf + buflen;
+	char *p;
+	int unit;
+
+	p = end - 1;
+	*p = '\0';
+	unit = base;
+	do {
+		if (p == begin)
+			return -EINVAL;
+		*--p = 'a' + (index % unit);
+		index = (index / unit) - 1;
+	} while (index >= 0);
+
+	memmove(begin, p, end - p);
+	memcpy(buf, prefix, strlen(prefix));
+
+	return 0;
+}
+
+/*
+ * The asynchronous part of sd_probe
+ */
+static void sd_probe_async(void *data, async_cookie_t cookie)
+{
+	struct scsi_disk *sdkp = data;
+	struct scsi_device *sdp;
+	struct gendisk *gd;
+	u32 index;
+	struct device *dev;
+
+	sdp = sdkp->device;
+	gd = sdkp->disk;
+	index = sdkp->index;
+	dev = &sdp->sdev_gendev;
+
+	gd->major = sd_major((index & 0xf0) >> 4);
+	gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
+	gd->minors = SD_MINORS;
+
+	gd->fops = &sd_fops;
+	gd->private_data = &sdkp->driver;
+	gd->queue = sdkp->device->request_queue;
+
+	/* defaults, until the device tells us otherwise */
+	sdp->sector_size = 512;
+	sdkp->capacity = 0;
+	sdkp->media_present = 1;
+	sdkp->write_prot = 0;
+	sdkp->cache_override = 0;
+	sdkp->WCE = 0;
+	sdkp->RCD = 0;
+	sdkp->ATO = 0;
+	sdkp->first_scan = 1;
+	sdkp->max_medium_access_timeouts = SD_MAX_MEDIUM_TIMEOUTS;
+
+	sd_revalidate_disk(gd);
+
+	blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
+	blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
+
+	gd->driverfs_dev = &sdp->sdev_gendev;
+	gd->flags = GENHD_FL_EXT_DEVT;
+	if (sdp->removable) {
+		gd->flags |= GENHD_FL_REMOVABLE;
+		gd->events |= DISK_EVENT_MEDIA_CHANGE;
+	}
+
+	add_disk(gd);
+	sd_dif_config_host(sdkp);
+
+	sd_revalidate_disk(gd);
+
+	sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
+		  sdp->removable ? "removable " : "");
+	scsi_autopm_put_device(sdp);
+	put_device(&sdkp->dev);
+}
+
+/**
+ *	sd_probe - called during driver initialization and whenever a
+ *	new scsi device is attached to the system. It is called once
+ *	for each scsi device (not just disks) present.
+ *	@dev: pointer to device object
+ *
+ *	Returns 0 if successful (or not interested in this scsi device 
+ *	(e.g. scanner)); 1 when there is an error.
+ *
+ *	Note: this function is invoked from the scsi mid-level.
+ *	This function sets up the mapping between a given 
+ *	<host,channel,id,lun> (found in sdp) and new device name 
+ *	(e.g. /dev/sda). More precisely it is the block device major 
+ *	and minor number that is chosen here.
+ *
+ *	Assume sd_probe is not re-entrant (for time being)
+ *	Also think about sd_probe() and sd_remove() running coincidentally.
+ **/
+static int sd_probe(struct device *dev)
+{
+	struct scsi_device *sdp = to_scsi_device(dev);
+	struct scsi_disk *sdkp;
+	struct gendisk *gd;
+	int index;
+	int error;
+
+	error = -ENODEV;
+	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
+		goto out;
+
+	SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
+					"sd_probe\n"));
+
+	error = -ENOMEM;
+	sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
+	if (!sdkp)
+		goto out;
+
+	gd = alloc_disk(SD_MINORS);
+	if (!gd)
+		goto out_free;
+
+	do {
+		if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
+			goto out_put;
+
+		spin_lock(&sd_index_lock);
+		error = ida_get_new(&sd_index_ida, &index);
+		spin_unlock(&sd_index_lock);
+	} while (error == -EAGAIN);
+
+	if (error) {
+		sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
+		goto out_put;
+	}
+
+	error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
+	if (error) {
+		sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
+		goto out_free_index;
+	}
+
+	sdkp->device = sdp;
+	sdkp->driver = &sd_template;
+	sdkp->disk = gd;
+	sdkp->index = index;
+	atomic_set(&sdkp->openers, 0);
+
+	if (!sdp->request_queue->rq_timeout) {
+		if (sdp->type != TYPE_MOD)
+			blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
+		else
+			blk_queue_rq_timeout(sdp->request_queue,
+					     SD_MOD_TIMEOUT);
+	}
+
+	device_initialize(&sdkp->dev);
+	sdkp->dev.parent = dev;
+	sdkp->dev.class = &sd_disk_class;
+	dev_set_name(&sdkp->dev, dev_name(dev));
+
+	if (device_add(&sdkp->dev))
+		goto out_free_index;
+
+	get_device(dev);
+	dev_set_drvdata(dev, sdkp);
+
+	get_device(&sdkp->dev);	/* prevent release before async_schedule */
+	async_schedule(sd_probe_async, sdkp);
+
+	return 0;
+
+ out_free_index:
+	spin_lock(&sd_index_lock);
+	ida_remove(&sd_index_ida, index);
+	spin_unlock(&sd_index_lock);
+ out_put:
+	put_disk(gd);
+ out_free:
+	kfree(sdkp);
+ out:
+	return error;
+}
+
+/**
+ *	sd_remove - called whenever a scsi disk (previously recognized by
+ *	sd_probe) is detached from the system. It is called (potentially
+ *	multiple times) during sd module unload.
+ *	@sdp: pointer to mid level scsi device object
+ *
+ *	Note: this function is invoked from the scsi mid-level.
+ *	This function potentially frees up a device name (e.g. /dev/sdc)
+ *	that could be re-used by a subsequent sd_probe().
+ *	This function is not called when the built-in sd driver is "exit-ed".
+ **/
+static int sd_remove(struct device *dev)
+{
+	struct scsi_disk *sdkp;
+
+	sdkp = dev_get_drvdata(dev);
+	scsi_autopm_get_device(sdkp->device);
+
+	async_synchronize_full();
+	blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
+	blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
+	device_del(&sdkp->dev);
+	del_gendisk(sdkp->disk);
+	sd_shutdown(dev);
+
+	mutex_lock(&sd_ref_mutex);
+	dev_set_drvdata(dev, NULL);
+	put_device(&sdkp->dev);
+	mutex_unlock(&sd_ref_mutex);
+
+	return 0;
+}
+
+/**
+ *	scsi_disk_release - Called to free the scsi_disk structure
+ *	@dev: pointer to embedded class device
+ *
+ *	sd_ref_mutex must be held entering this routine.  Because it is
+ *	called on last put, you should always use the scsi_disk_get()
+ *	scsi_disk_put() helpers which manipulate the semaphore directly
+ *	and never do a direct put_device.
+ **/
+static void scsi_disk_release(struct device *dev)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+	struct gendisk *disk = sdkp->disk;
+	
+	spin_lock(&sd_index_lock);
+	ida_remove(&sd_index_ida, sdkp->index);
+	spin_unlock(&sd_index_lock);
+
+	disk->private_data = NULL;
+	put_disk(disk);
+	put_device(&sdkp->device->sdev_gendev);
+
+	kfree(sdkp);
+}
+
+static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
+{
+	unsigned char cmd[6] = { START_STOP };	/* START_VALID */
+	struct scsi_sense_hdr sshdr;
+	struct scsi_device *sdp = sdkp->device;
+	int res;
+
+	if (start)
+		cmd[4] |= 1;	/* START */
+
+	if (sdp->start_stop_pwr_cond)
+		cmd[4] |= start ? 1 << 4 : 3 << 4;	/* Active or Standby */
+
+	if (!scsi_device_online(sdp))
+		return -ENODEV;
+
+	res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
+			       SD_TIMEOUT, SD_MAX_RETRIES, NULL);
+	if (res) {
+		sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
+		sd_print_result(sdkp, res);
+		if (driver_byte(res) & DRIVER_SENSE)
+			sd_print_sense_hdr(sdkp, &sshdr);
+	}
+
+	return res;
+}
+
+/*
+ * Send a SYNCHRONIZE CACHE instruction down to the device through
+ * the normal SCSI command structure.  Wait for the command to
+ * complete.
+ */
+static void sd_shutdown(struct device *dev)
+{
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+
+	if (!sdkp)
+		return;         /* this can happen */
+
+	if (pm_runtime_suspended(dev))
+		goto exit;
+
+	if (sdkp->WCE) {
+		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
+		sd_sync_cache(sdkp);
+	}
+
+	if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
+		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
+		sd_start_stop_device(sdkp, 0);
+	}
+
+exit:
+	scsi_disk_put(sdkp);
+}
+
+static int sd_suspend(struct device *dev, pm_message_t mesg)
+{
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+	int ret = 0;
+
+	if (!sdkp)
+		return 0;	/* this can happen */
+
+	if (sdkp->WCE) {
+		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
+		ret = sd_sync_cache(sdkp);
+		if (ret)
+			goto done;
+	}
+
+	if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
+		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
+		ret = sd_start_stop_device(sdkp, 0);
+	}
+
+done:
+	scsi_disk_put(sdkp);
+	return ret;
+}
+
+static int sd_resume(struct device *dev)
+{
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+	int ret = 0;
+
+	if (!sdkp->device->manage_start_stop)
+		goto done;
+
+	sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
+	ret = sd_start_stop_device(sdkp, 1);
+
+done:
+	scsi_disk_put(sdkp);
+	return ret;
+}
+
+/**
+ *	init_sd - entry point for this driver (both when built in or when
+ *	a module).
+ *
+ *	Note: this function registers this driver with the scsi mid-level.
+ **/
+static int __init init_sd(void)
+{
+	int majors = 0, i, err;
+
+	SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
+
+	for (i = 0; i < SD_MAJORS; i++)
+		if (register_blkdev(sd_major(i), "sd") == 0)
+			majors++;
+
+	if (!majors)
+		return -ENODEV;
+
+	err = class_register(&sd_disk_class);
+	if (err)
+		goto err_out;
+
+	sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
+					 0, 0, NULL);
+	if (!sd_cdb_cache) {
+		printk(KERN_ERR "sd: can't init extended cdb cache\n");
+		goto err_out_class;
+	}
+
+	sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
+	if (!sd_cdb_pool) {
+		printk(KERN_ERR "sd: can't init extended cdb pool\n");
+		goto err_out_cache;
+	}
+
+	err = scsi_register_driver(&sd_template.gendrv);
+	if (err)
+		goto err_out_driver;
+
+	return 0;
+
+err_out_driver:
+	mempool_destroy(sd_cdb_pool);
+
+err_out_cache:
+	kmem_cache_destroy(sd_cdb_cache);
+
+err_out_class:
+	class_unregister(&sd_disk_class);
+err_out:
+	for (i = 0; i < SD_MAJORS; i++)
+		unregister_blkdev(sd_major(i), "sd");
+	return err;
+}
+
+/**
+ *	exit_sd - exit point for this driver (when it is a module).
+ *
+ *	Note: this function unregisters this driver from the scsi mid-level.
+ **/
+static void __exit exit_sd(void)
+{
+	int i;
+
+	SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
+
+	scsi_unregister_driver(&sd_template.gendrv);
+	mempool_destroy(sd_cdb_pool);
+	kmem_cache_destroy(sd_cdb_cache);
+
+	class_unregister(&sd_disk_class);
+
+	for (i = 0; i < SD_MAJORS; i++)
+		unregister_blkdev(sd_major(i), "sd");
+}
+
+module_init(init_sd);
+module_exit(exit_sd);
+
+static void sd_print_sense_hdr(struct scsi_disk *sdkp,
+			       struct scsi_sense_hdr *sshdr)
+{
+	sd_printk(KERN_INFO, sdkp, " ");
+	scsi_show_sense_hdr(sshdr);
+	sd_printk(KERN_INFO, sdkp, " ");
+	scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
+}
+
+static void sd_print_result(struct scsi_disk *sdkp, int result)
+{
+	sd_printk(KERN_INFO, sdkp, " ");
+	scsi_show_result(result);
+}
+