[deliverable/linux.git] / drivers / target / target_core_iblock.c

/*******************************************************************************
 * Filename:  target_core_iblock.c
 *
 * This file contains the Storage Engine  <-> Linux BlockIO transport
 * specific functions.
 *
 * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
 * Copyright (c) 2005, 2006, 2007 SBE, Inc.
 * Copyright (c) 2007-2010 Rising Tide Systems
 * Copyright (c) 2008-2010 Linux-iSCSI.org
 *
 * Nicholas A. Bellinger <nab@kernel.org>
 *
 * 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/string.h>
#include <linux/parser.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/bio.h>
#include <linux/genhd.h>
#include <linux/file.h>
#include <linux/module.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>

#include <target/target_core_base.h>
#include <target/target_core_backend.h>

#include "target_core_iblock.h"

static struct se_subsystem_api iblock_template;

static void iblock_bio_done(struct bio *, int);

/*	iblock_attach_hba(): (Part of se_subsystem_api_t template)
 *
 *
 */
static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
{
	pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
		" Generic Target Core Stack %s\n", hba->hba_id,
		IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
	return 0;
}

static void iblock_detach_hba(struct se_hba *hba)
{
}

static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name)
{
	struct iblock_dev *ib_dev = NULL;

	ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
	if (!ib_dev) {
		pr_err("Unable to allocate struct iblock_dev\n");
		return NULL;
	}

	pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);

	return ib_dev;
}

static struct se_device *iblock_create_virtdevice(
	struct se_hba *hba,
	struct se_subsystem_dev *se_dev,
	void *p)
{
	struct iblock_dev *ib_dev = p;
	struct se_device *dev;
	struct se_dev_limits dev_limits;
	struct block_device *bd = NULL;
	struct request_queue *q;
	struct queue_limits *limits;
	u32 dev_flags = 0;
	int ret = -EINVAL;

	if (!ib_dev) {
		pr_err("Unable to locate struct iblock_dev parameter\n");
		return ERR_PTR(ret);
	}
	memset(&dev_limits, 0, sizeof(struct se_dev_limits));
	/*
	 * These settings need to be made tunable..
	 */
	ib_dev->ibd_bio_set = bioset_create(32, 0);
	if (!ib_dev->ibd_bio_set) {
		pr_err("IBLOCK: Unable to create bioset()\n");
		return ERR_PTR(-ENOMEM);
	}
	pr_debug("IBLOCK: Created bio_set()\n");
	/*
	 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
	 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
	 */
	pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
			ib_dev->ibd_udev_path);

	bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
				FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev);
	if (IS_ERR(bd)) {
		ret = PTR_ERR(bd);
		goto failed;
	}
	/*
	 * Setup the local scope queue_limits from struct request_queue->limits
	 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
	 */
	q = bdev_get_queue(bd);
	limits = &dev_limits.limits;
	limits->logical_block_size = bdev_logical_block_size(bd);
	limits->max_hw_sectors = queue_max_hw_sectors(q);
	limits->max_sectors = queue_max_sectors(q);
	dev_limits.hw_queue_depth = q->nr_requests;
	dev_limits.queue_depth = q->nr_requests;

	ib_dev->ibd_bd = bd;

	dev = transport_add_device_to_core_hba(hba,
			&iblock_template, se_dev, dev_flags, ib_dev,
			&dev_limits, "IBLOCK", IBLOCK_VERSION);
	if (!dev)
		goto failed;

	/*
	 * Check if the underlying struct block_device request_queue supports
	 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
	 * in ATA and we need to set TPE=1
	 */
	if (blk_queue_discard(q)) {
		dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
				q->limits.max_discard_sectors;
		/*
		 * Currently hardcoded to 1 in Linux/SCSI code..
		 */
		dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
		dev->se_sub_dev->se_dev_attrib.unmap_granularity =
				q->limits.discard_granularity >> 9;
		dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
				q->limits.discard_alignment;

		pr_debug("IBLOCK: BLOCK Discard support available,"
				" disabled by default\n");
	}

	if (blk_queue_nonrot(q))
		dev->se_sub_dev->se_dev_attrib.is_nonrot = 1;

	return dev;

failed:
	if (ib_dev->ibd_bio_set) {
		bioset_free(ib_dev->ibd_bio_set);
		ib_dev->ibd_bio_set = NULL;
	}
	ib_dev->ibd_bd = NULL;
	return ERR_PTR(ret);
}

static void iblock_free_device(void *p)
{
	struct iblock_dev *ib_dev = p;

	if (ib_dev->ibd_bd != NULL)
		blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
	if (ib_dev->ibd_bio_set != NULL)
		bioset_free(ib_dev->ibd_bio_set);
	kfree(ib_dev);
}

static inline struct iblock_req *IBLOCK_REQ(struct se_task *task)
{
	return container_of(task, struct iblock_req, ib_task);
}

static struct se_task *
iblock_alloc_task(unsigned char *cdb)
{
	struct iblock_req *ib_req;

	ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
	if (!ib_req) {
		pr_err("Unable to allocate memory for struct iblock_req\n");
		return NULL;
	}

	atomic_set(&ib_req->ib_bio_cnt, 0);
	return &ib_req->ib_task;
}

static unsigned long long iblock_emulate_read_cap_with_block_size(
	struct se_device *dev,
	struct block_device *bd,
	struct request_queue *q)
{
	unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
					bdev_logical_block_size(bd)) - 1);
	u32 block_size = bdev_logical_block_size(bd);

	if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
		return blocks_long;

	switch (block_size) {
	case 4096:
		switch (dev->se_sub_dev->se_dev_attrib.block_size) {
		case 2048:
			blocks_long <<= 1;
			break;
		case 1024:
			blocks_long <<= 2;
			break;
		case 512:
			blocks_long <<= 3;
		default:
			break;
		}
		break;
	case 2048:
		switch (dev->se_sub_dev->se_dev_attrib.block_size) {
		case 4096:
			blocks_long >>= 1;
			break;
		case 1024:
			blocks_long <<= 1;
			break;
		case 512:
			blocks_long <<= 2;
			break;
		default:
			break;
		}
		break;
	case 1024:
		switch (dev->se_sub_dev->se_dev_attrib.block_size) {
		case 4096:
			blocks_long >>= 2;
			break;
		case 2048:
			blocks_long >>= 1;
			break;
		case 512:
			blocks_long <<= 1;
			break;
		default:
			break;
		}
		break;
	case 512:
		switch (dev->se_sub_dev->se_dev_attrib.block_size) {
		case 4096:
			blocks_long >>= 3;
			break;
		case 2048:
			blocks_long >>= 2;
			break;
		case 1024:
			blocks_long >>= 1;
			break;
		default:
			break;
		}
		break;
	default:
		break;
	}

	return blocks_long;
}

static void iblock_end_io_flush(struct bio *bio, int err)
{
	struct se_cmd *cmd = bio->bi_private;

	if (err)
		pr_err("IBLOCK: cache flush failed: %d\n", err);

	if (cmd)
		transport_complete_sync_cache(cmd, err == 0);
	bio_put(bio);
}

/*
 * Implement SYCHRONIZE CACHE.  Note that we can't handle lba ranges and must
 * always flush the whole cache.
 */
static void iblock_emulate_sync_cache(struct se_task *task)
{
	struct se_cmd *cmd = task->task_se_cmd;
	struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
	int immed = (cmd->t_task_cdb[1] & 0x2);
	struct bio *bio;

	/*
	 * If the Immediate bit is set, queue up the GOOD response
	 * for this SYNCHRONIZE_CACHE op.
	 */
	if (immed)
		transport_complete_sync_cache(cmd, 1);

	bio = bio_alloc(GFP_KERNEL, 0);
	bio->bi_end_io = iblock_end_io_flush;
	bio->bi_bdev = ib_dev->ibd_bd;
	if (!immed)
		bio->bi_private = cmd;
	submit_bio(WRITE_FLUSH, bio);
}

static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
{
	struct iblock_dev *ibd = dev->dev_ptr;
	struct block_device *bd = ibd->ibd_bd;
	int barrier = 0;

	return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
}

static void iblock_free_task(struct se_task *task)
{
	kfree(IBLOCK_REQ(task));
}

enum {
	Opt_udev_path, Opt_force, Opt_err
};

static match_table_t tokens = {
	{Opt_udev_path, "udev_path=%s"},
	{Opt_force, "force=%d"},
	{Opt_err, NULL}
};

static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
					       struct se_subsystem_dev *se_dev,
					       const char *page, ssize_t count)
{
	struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
	char *orig, *ptr, *arg_p, *opts;
	substring_t args[MAX_OPT_ARGS];
	int ret = 0, token;

	opts = kstrdup(page, GFP_KERNEL);
	if (!opts)
		return -ENOMEM;

	orig = opts;

	while ((ptr = strsep(&opts, ",\n")) != NULL) {
		if (!*ptr)
			continue;

		token = match_token(ptr, tokens, args);
		switch (token) {
		case Opt_udev_path:
			if (ib_dev->ibd_bd) {
				pr_err("Unable to set udev_path= while"
					" ib_dev->ibd_bd exists\n");
				ret = -EEXIST;
				goto out;
			}
			arg_p = match_strdup(&args[0]);
			if (!arg_p) {
				ret = -ENOMEM;
				break;
			}
			snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
					"%s", arg_p);
			kfree(arg_p);
			pr_debug("IBLOCK: Referencing UDEV path: %s\n",
					ib_dev->ibd_udev_path);
			ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
			break;
		case Opt_force:
			break;
		default:
			break;
		}
	}

out:
	kfree(orig);
	return (!ret) ? count : ret;
}

static ssize_t iblock_check_configfs_dev_params(
	struct se_hba *hba,
	struct se_subsystem_dev *se_dev)
{
	struct iblock_dev *ibd = se_dev->se_dev_su_ptr;

	if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
		pr_err("Missing udev_path= parameters for IBLOCK\n");
		return -EINVAL;
	}

	return 0;
}

static ssize_t iblock_show_configfs_dev_params(
	struct se_hba *hba,
	struct se_subsystem_dev *se_dev,
	char *b)
{
	struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
	struct block_device *bd = ibd->ibd_bd;
	char buf[BDEVNAME_SIZE];
	ssize_t bl = 0;

	if (bd)
		bl += sprintf(b + bl, "iBlock device: %s",
				bdevname(bd, buf));
	if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
		bl += sprintf(b + bl, "  UDEV PATH: %s\n",
				ibd->ibd_udev_path);
	} else
		bl += sprintf(b + bl, "\n");

	bl += sprintf(b + bl, "        ");
	if (bd) {
		bl += sprintf(b + bl, "Major: %d Minor: %d  %s\n",
			MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
			"" : (bd->bd_holder == ibd) ?
			"CLAIMED: IBLOCK" : "CLAIMED: OS");
	} else {
		bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
	}

	return bl;
}

static void iblock_bio_destructor(struct bio *bio)
{
	struct se_task *task = bio->bi_private;
	struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;

	bio_free(bio, ib_dev->ibd_bio_set);
}

static struct bio *
iblock_get_bio(struct se_task *task, sector_t lba, u32 sg_num)
{
	struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
	struct iblock_req *ib_req = IBLOCK_REQ(task);
	struct bio *bio;

	/*
	 * Only allocate as many vector entries as the bio code allows us to,
	 * we'll loop later on until we have handled the whole request.
	 */
	if (sg_num > BIO_MAX_PAGES)
		sg_num = BIO_MAX_PAGES;

	bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
	if (!bio) {
		pr_err("Unable to allocate memory for bio\n");
		return NULL;
	}

	pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:"
		" %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set);
	pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size);

	bio->bi_bdev = ib_dev->ibd_bd;
	bio->bi_private = task;
	bio->bi_destructor = iblock_bio_destructor;
	bio->bi_end_io = &iblock_bio_done;
	bio->bi_sector = lba;
	atomic_inc(&ib_req->ib_bio_cnt);

	pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector);
	pr_debug("Set ib_req->ib_bio_cnt: %d\n",
			atomic_read(&ib_req->ib_bio_cnt));
	return bio;
}

static int iblock_do_task(struct se_task *task)
{
	struct se_cmd *cmd = task->task_se_cmd;
	struct se_device *dev = cmd->se_dev;
	struct bio *bio;
	struct bio_list list;
	struct scatterlist *sg;
	u32 i, sg_num = task->task_sg_nents;
	sector_t block_lba;
	struct blk_plug plug;
	int rw;

	if (task->task_data_direction == DMA_TO_DEVICE) {
		/*
		 * Force data to disk if we pretend to not have a volatile
		 * write cache, or the initiator set the Force Unit Access bit.
		 */
		if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
		    (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
		     (cmd->se_cmd_flags & SCF_FUA)))
			rw = WRITE_FUA;
		else
			rw = WRITE;
	} else {
		rw = READ;
	}

	/*
	 * Do starting conversion up from non 512-byte blocksize with
	 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
	 */
	if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
		block_lba = (task->task_lba << 3);
	else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
		block_lba = (task->task_lba << 2);
	else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
		block_lba = (task->task_lba << 1);
	else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
		block_lba = task->task_lba;
	else {
		pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
				" %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
		return -ENOSYS;
	}

	bio = iblock_get_bio(task, block_lba, sg_num);
	if (!bio) {
		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
		return -ENOMEM;
	}

	bio_list_init(&list);
	bio_list_add(&list, bio);

	for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
		/*
		 * XXX: if the length the device accepts is shorter than the
		 *	length of the S/G list entry this will cause and
		 *	endless loop.  Better hope no driver uses huge pages.
		 */
		while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
				!= sg->length) {
			bio = iblock_get_bio(task, block_lba, sg_num);
			if (!bio)
				goto fail;
			bio_list_add(&list, bio);
		}

		/* Always in 512 byte units for Linux/Block */
		block_lba += sg->length >> IBLOCK_LBA_SHIFT;
		sg_num--;
	}

	blk_start_plug(&plug);
	while ((bio = bio_list_pop(&list)))
		submit_bio(rw, bio);
	blk_finish_plug(&plug);

	return 0;

fail:
	while ((bio = bio_list_pop(&list)))
		bio_put(bio);
	cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
	return -ENOMEM;
}

static u32 iblock_get_device_rev(struct se_device *dev)
{
	return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
}

static u32 iblock_get_device_type(struct se_device *dev)
{
	return TYPE_DISK;
}

static sector_t iblock_get_blocks(struct se_device *dev)
{
	struct iblock_dev *ibd = dev->dev_ptr;
	struct block_device *bd = ibd->ibd_bd;
	struct request_queue *q = bdev_get_queue(bd);

	return iblock_emulate_read_cap_with_block_size(dev, bd, q);
}

static void iblock_bio_done(struct bio *bio, int err)
{
	struct se_task *task = bio->bi_private;
	struct iblock_req *ibr = IBLOCK_REQ(task);

	/*
	 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
	 */
	if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
		err = -EIO;

	if (err != 0) {
		pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
			" err: %d\n", bio, err);
		/*
		 * Bump the ib_bio_err_cnt and release bio.
		 */
		atomic_inc(&ibr->ib_bio_err_cnt);
		smp_mb__after_atomic_inc();
	}

	bio_put(bio);

	if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
		return;

	pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
		 task, bio, task->task_lba,
		 (unsigned long long)bio->bi_sector, err);

	transport_complete_task(task, !atomic_read(&ibr->ib_bio_err_cnt));
}

static struct se_subsystem_api iblock_template = {
	.name			= "iblock",
	.owner			= THIS_MODULE,
	.transport_type		= TRANSPORT_PLUGIN_VHBA_PDEV,
	.write_cache_emulated	= 1,
	.fua_write_emulated	= 1,
	.attach_hba		= iblock_attach_hba,
	.detach_hba		= iblock_detach_hba,
	.allocate_virtdevice	= iblock_allocate_virtdevice,
	.create_virtdevice	= iblock_create_virtdevice,
	.free_device		= iblock_free_device,
	.alloc_task		= iblock_alloc_task,
	.do_task		= iblock_do_task,
	.do_discard		= iblock_do_discard,
	.do_sync_cache		= iblock_emulate_sync_cache,
	.free_task		= iblock_free_task,
	.check_configfs_dev_params = iblock_check_configfs_dev_params,
	.set_configfs_dev_params = iblock_set_configfs_dev_params,
	.show_configfs_dev_params = iblock_show_configfs_dev_params,
	.get_device_rev		= iblock_get_device_rev,
	.get_device_type	= iblock_get_device_type,
	.get_blocks		= iblock_get_blocks,
};

static int __init iblock_module_init(void)
{
	return transport_subsystem_register(&iblock_template);
}

static void iblock_module_exit(void)
{
	transport_subsystem_release(&iblock_template);
}

MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
MODULE_AUTHOR("nab@Linux-iSCSI.org");
MODULE_LICENSE("GPL");

module_init(iblock_module_init);
module_exit(iblock_module_exit);
Commit	Line	Data
c66ac9db NB	1	/*******************************************************************************
	2	* Filename: target_core_iblock.c
	3	*
	4	* This file contains the Storage Engine <-> Linux BlockIO transport
	5	* specific functions.
	6	*
	7	* Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
	8	* Copyright (c) 2005, 2006, 2007 SBE, Inc.
	9	* Copyright (c) 2007-2010 Rising Tide Systems
	10	* Copyright (c) 2008-2010 Linux-iSCSI.org
	11	*
	12	* Nicholas A. Bellinger <nab@kernel.org>
	13	*
	14	* This program is free software; you can redistribute it and/or modify
	15	* it under the terms of the GNU General Public License as published by
	16	* the Free Software Foundation; either version 2 of the License, or
	17	* (at your option) any later version.
	18	*
	19	* This program is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License
	25	* along with this program; if not, write to the Free Software
	26	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	27	*
	28	******************************************************************************/
	29
c66ac9db NB	30	#include <linux/string.h>
	31	#include <linux/parser.h>
	32	#include <linux/timer.h>
	33	#include <linux/fs.h>
	34	#include <linux/blkdev.h>
	35	#include <linux/slab.h>
	36	#include <linux/spinlock.h>
c66ac9db NB	37	#include <linux/bio.h>
	38	#include <linux/genhd.h>
	39	#include <linux/file.h>
827509e3	40	#include <linux/module.h>
c66ac9db NB	41	#include <scsi/scsi.h>
	42	#include <scsi/scsi_host.h>
	43
	44	#include <target/target_core_base.h>
c4795fb2	45	#include <target/target_core_backend.h>
c66ac9db NB	46
	47	#include "target_core_iblock.h"
	48
c66ac9db NB	49	static struct se_subsystem_api iblock_template;
	50
	51	static void iblock_bio_done(struct bio *, int);
	52
	53	/* iblock_attach_hba(): (Part of se_subsystem_api_t template)
	54	*
	55	*
	56	*/
	57	static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
	58	{
6708bb27	59	pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
c66ac9db NB	60	" Generic Target Core Stack %s\n", hba->hba_id,
c66ac9db NB	61	IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
c66ac9db NB	62	return 0;
	63	}
	64
	65	static void iblock_detach_hba(struct se_hba *hba)
	66	{
c66ac9db NB	67	}
	68
	69	static void iblock_allocate_virtdevice(struct se_hba hba, const char *name)
	70	{
	71	struct iblock_dev *ib_dev = NULL;
c66ac9db NB	72
c66ac9db NB	73	ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
6708bb27 AG	74	if (!ib_dev) {
6708bb27 AG	75	pr_err("Unable to allocate struct iblock_dev\n");
c66ac9db NB	76	return NULL;
c66ac9db NB	77	}
c66ac9db	78
6708bb27	79	pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
c66ac9db NB	80
	81	return ib_dev;
	82	}
	83
	84	static struct se_device *iblock_create_virtdevice(
	85	struct se_hba *hba,
	86	struct se_subsystem_dev *se_dev,
	87	void *p)
	88	{
	89	struct iblock_dev *ib_dev = p;
	90	struct se_device *dev;
	91	struct se_dev_limits dev_limits;
	92	struct block_device *bd = NULL;
	93	struct request_queue *q;
	94	struct queue_limits *limits;
	95	u32 dev_flags = 0;
613640e4	96	int ret = -EINVAL;
c66ac9db	97
6708bb27 AG	98	if (!ib_dev) {
6708bb27 AG	99	pr_err("Unable to locate struct iblock_dev parameter\n");
613640e4	100	return ERR_PTR(ret);
c66ac9db NB	101	}
	102	memset(&dev_limits, 0, sizeof(struct se_dev_limits));
	103	/*
	104	* These settings need to be made tunable..
	105	*/
48cfe37c	106	ib_dev->ibd_bio_set = bioset_create(32, 0);
6708bb27 AG	107	if (!ib_dev->ibd_bio_set) {
6708bb27 AG	108	pr_err("IBLOCK: Unable to create bioset()\n");
613640e4	109	return ERR_PTR(-ENOMEM);
c66ac9db	110	}
6708bb27	111	pr_debug("IBLOCK: Created bio_set()\n");
c66ac9db NB	112	/*
	113	* iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
	114	* must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
	115	*/
6708bb27	116	pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
c66ac9db NB	117	ib_dev->ibd_udev_path);
	118
	119	bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
	120	FMODE_WRITE\|FMODE_READ\|FMODE_EXCL, ib_dev);
613640e4 NB	121	if (IS_ERR(bd)) {
613640e4 NB	122	ret = PTR_ERR(bd);
c66ac9db	123	goto failed;
613640e4	124	}
c66ac9db NB	125	/*
	126	* Setup the local scope queue_limits from struct request_queue->limits
	127	* to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
	128	*/
	129	q = bdev_get_queue(bd);
	130	limits = &dev_limits.limits;
	131	limits->logical_block_size = bdev_logical_block_size(bd);
	132	limits->max_hw_sectors = queue_max_hw_sectors(q);
	133	limits->max_sectors = queue_max_sectors(q);
8f3d14e2 NB	134	dev_limits.hw_queue_depth = q->nr_requests;
8f3d14e2 NB	135	dev_limits.queue_depth = q->nr_requests;
c66ac9db	136
c66ac9db NB	137	ib_dev->ibd_bd = bd;
	138
	139	dev = transport_add_device_to_core_hba(hba,
5951146d	140	&iblock_template, se_dev, dev_flags, ib_dev,
c66ac9db	141	&dev_limits, "IBLOCK", IBLOCK_VERSION);
6708bb27	142	if (!dev)
c66ac9db NB	143	goto failed;
c66ac9db NB	144
c66ac9db NB	145	/*
	146	* Check if the underlying struct block_device request_queue supports
	147	* the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
	148	* in ATA and we need to set TPE=1
	149	*/
613640e4	150	if (blk_queue_discard(q)) {
e3d6f909	151	dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
c66ac9db NB	152	q->limits.max_discard_sectors;
	153	/*
	154	* Currently hardcoded to 1 in Linux/SCSI code..
	155	*/
e3d6f909 AG	156	dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
e3d6f909 AG	157	dev->se_sub_dev->se_dev_attrib.unmap_granularity =
7347b5ff	158	q->limits.discard_granularity >> 9;
e3d6f909	159	dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
c66ac9db NB	160	q->limits.discard_alignment;
c66ac9db NB	161
6708bb27	162	pr_debug("IBLOCK: BLOCK Discard support available,"
c66ac9db NB	163	" disabled by default\n");
	164	}
	165
e22a7f07 RD	166	if (blk_queue_nonrot(q))
	167	dev->se_sub_dev->se_dev_attrib.is_nonrot = 1;
	168
c66ac9db NB	169	return dev;
	170
	171	failed:
	172	if (ib_dev->ibd_bio_set) {
	173	bioset_free(ib_dev->ibd_bio_set);
	174	ib_dev->ibd_bio_set = NULL;
	175	}
	176	ib_dev->ibd_bd = NULL;
613640e4	177	return ERR_PTR(ret);
c66ac9db NB	178	}
	179
	180	static void iblock_free_device(void *p)
	181	{
	182	struct iblock_dev *ib_dev = p;
	183
bc665524 NB	184	if (ib_dev->ibd_bd != NULL)
	185	blkdev_put(ib_dev->ibd_bd, FMODE_WRITE\|FMODE_READ\|FMODE_EXCL);
	186	if (ib_dev->ibd_bio_set != NULL)
	187	bioset_free(ib_dev->ibd_bio_set);
c66ac9db NB	188	kfree(ib_dev);
	189	}
	190
	191	static inline struct iblock_req IBLOCK_REQ(struct se_task task)
	192	{
	193	return container_of(task, struct iblock_req, ib_task);
	194	}
	195
	196	static struct se_task *
6708bb27	197	iblock_alloc_task(unsigned char *cdb)
c66ac9db NB	198	{
	199	struct iblock_req *ib_req;
	200
	201	ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
6708bb27 AG	202	if (!ib_req) {
6708bb27 AG	203	pr_err("Unable to allocate memory for struct iblock_req\n");
c66ac9db NB	204	return NULL;
	205	}
	206
c66ac9db NB	207	atomic_set(&ib_req->ib_bio_cnt, 0);
	208	return &ib_req->ib_task;
	209	}
	210
	211	static unsigned long long iblock_emulate_read_cap_with_block_size(
	212	struct se_device *dev,
	213	struct block_device *bd,
	214	struct request_queue *q)
	215	{
	216	unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
	217	bdev_logical_block_size(bd)) - 1);
	218	u32 block_size = bdev_logical_block_size(bd);
	219
e3d6f909	220	if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
c66ac9db NB	221	return blocks_long;
	222
	223	switch (block_size) {
	224	case 4096:
e3d6f909	225	switch (dev->se_sub_dev->se_dev_attrib.block_size) {
c66ac9db NB	226	case 2048:
	227	blocks_long <<= 1;
	228	break;
	229	case 1024:
	230	blocks_long <<= 2;
	231	break;
	232	case 512:
	233	blocks_long <<= 3;
	234	default:
	235	break;
	236	}
	237	break;
	238	case 2048:
e3d6f909	239	switch (dev->se_sub_dev->se_dev_attrib.block_size) {
c66ac9db NB	240	case 4096:
	241	blocks_long >>= 1;
	242	break;
	243	case 1024:
	244	blocks_long <<= 1;
	245	break;
	246	case 512:
	247	blocks_long <<= 2;
	248	break;
	249	default:
	250	break;
	251	}
	252	break;
	253	case 1024:
e3d6f909	254	switch (dev->se_sub_dev->se_dev_attrib.block_size) {
c66ac9db NB	255	case 4096:
	256	blocks_long >>= 2;
	257	break;
	258	case 2048:
	259	blocks_long >>= 1;
	260	break;
	261	case 512:
	262	blocks_long <<= 1;
	263	break;
	264	default:
	265	break;
	266	}
	267	break;
	268	case 512:
e3d6f909	269	switch (dev->se_sub_dev->se_dev_attrib.block_size) {
c66ac9db NB	270	case 4096:
	271	blocks_long >>= 3;
	272	break;
	273	case 2048:
	274	blocks_long >>= 2;
	275	break;
	276	case 1024:
	277	blocks_long >>= 1;
	278	break;
	279	default:
	280	break;
	281	}
	282	break;
	283	default:
	284	break;
	285	}
	286
	287	return blocks_long;
	288	}
	289
df5fa691 CH	290	static void iblock_end_io_flush(struct bio *bio, int err)
	291	{
	292	struct se_cmd *cmd = bio->bi_private;
	293
	294	if (err)
	295	pr_err("IBLOCK: cache flush failed: %d\n", err);
	296
	297	if (cmd)
	298	transport_complete_sync_cache(cmd, err == 0);
	299	bio_put(bio);
	300	}
	301
c66ac9db	302	/*
df5fa691 CH	303	* Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
df5fa691 CH	304	* always flush the whole cache.
c66ac9db NB	305	*/
	306	static void iblock_emulate_sync_cache(struct se_task *task)
	307	{
e3d6f909	308	struct se_cmd *cmd = task->task_se_cmd;
c66ac9db	309	struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
a1d8b49a	310	int immed = (cmd->t_task_cdb[1] & 0x2);
df5fa691	311	struct bio *bio;
c66ac9db NB	312
	313	/*
	314	* If the Immediate bit is set, queue up the GOOD response
df5fa691	315	* for this SYNCHRONIZE_CACHE op.
c66ac9db NB	316	*/
	317	if (immed)
	318	transport_complete_sync_cache(cmd, 1);
	319
df5fa691 CH	320	bio = bio_alloc(GFP_KERNEL, 0);
	321	bio->bi_end_io = iblock_end_io_flush;
	322	bio->bi_bdev = ib_dev->ibd_bd;
c66ac9db	323	if (!immed)
df5fa691 CH	324	bio->bi_private = cmd;
df5fa691 CH	325	submit_bio(WRITE_FLUSH, bio);
c66ac9db NB	326	}
c66ac9db NB	327
c66ac9db NB	328	static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
	329	{
	330	struct iblock_dev *ibd = dev->dev_ptr;
	331	struct block_device *bd = ibd->ibd_bd;
	332	int barrier = 0;
	333
	334	return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
	335	}
	336
	337	static void iblock_free_task(struct se_task *task)
	338	{
dbbf3e94	339	kfree(IBLOCK_REQ(task));
c66ac9db NB	340	}
	341
	342	enum {
	343	Opt_udev_path, Opt_force, Opt_err
	344	};
	345
	346	static match_table_t tokens = {
	347	{Opt_udev_path, "udev_path=%s"},
	348	{Opt_force, "force=%d"},
	349	{Opt_err, NULL}
	350	};
	351
	352	static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
	353	struct se_subsystem_dev *se_dev,
	354	const char *page, ssize_t count)
	355	{
	356	struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
6d180253	357	char orig, ptr, arg_p, opts;
c66ac9db	358	substring_t args[MAX_OPT_ARGS];
21bca31c	359	int ret = 0, token;
c66ac9db NB	360
	361	opts = kstrdup(page, GFP_KERNEL);
	362	if (!opts)
	363	return -ENOMEM;
	364
	365	orig = opts;
	366
90c161b6	367	while ((ptr = strsep(&opts, ",\n")) != NULL) {
c66ac9db NB	368	if (!*ptr)
	369	continue;
	370
	371	token = match_token(ptr, tokens, args);
	372	switch (token) {
	373	case Opt_udev_path:
	374	if (ib_dev->ibd_bd) {
6708bb27	375	pr_err("Unable to set udev_path= while"
c66ac9db NB	376	" ib_dev->ibd_bd exists\n");
	377	ret = -EEXIST;
	378	goto out;
	379	}
6d180253 JJ	380	arg_p = match_strdup(&args[0]);
	381	if (!arg_p) {
	382	ret = -ENOMEM;
	383	break;
	384	}
	385	snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
	386	"%s", arg_p);
	387	kfree(arg_p);
6708bb27	388	pr_debug("IBLOCK: Referencing UDEV path: %s\n",
c66ac9db NB	389	ib_dev->ibd_udev_path);
	390	ib_dev->ibd_flags \|= IBDF_HAS_UDEV_PATH;
	391	break;
	392	case Opt_force:
c66ac9db NB	393	break;
	394	default:
	395	break;
	396	}
	397	}
	398
	399	out:
	400	kfree(orig);
	401	return (!ret) ? count : ret;
	402	}
	403
	404	static ssize_t iblock_check_configfs_dev_params(
	405	struct se_hba *hba,
	406	struct se_subsystem_dev *se_dev)
	407	{
	408	struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
	409
	410	if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
6708bb27	411	pr_err("Missing udev_path= parameters for IBLOCK\n");
e3d6f909	412	return -EINVAL;
c66ac9db NB	413	}
	414
	415	return 0;
	416	}
	417
	418	static ssize_t iblock_show_configfs_dev_params(
	419	struct se_hba *hba,
	420	struct se_subsystem_dev *se_dev,
	421	char *b)
	422	{
	423	struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
	424	struct block_device *bd = ibd->ibd_bd;
	425	char buf[BDEVNAME_SIZE];
	426	ssize_t bl = 0;
	427
	428	if (bd)
	429	bl += sprintf(b + bl, "iBlock device: %s",
	430	bdevname(bd, buf));
	431	if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
	432	bl += sprintf(b + bl, " UDEV PATH: %s\n",
	433	ibd->ibd_udev_path);
	434	} else
	435	bl += sprintf(b + bl, "\n");
	436
	437	bl += sprintf(b + bl, " ");
	438	if (bd) {
	439	bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
21bca31c	440	MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
8359cf43	441	"" : (bd->bd_holder == ibd) ?
c66ac9db NB	442	"CLAIMED: IBLOCK" : "CLAIMED: OS");
c66ac9db NB	443	} else {
21bca31c	444	bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
c66ac9db NB	445	}
	446
	447	return bl;
	448	}
	449
	450	static void iblock_bio_destructor(struct bio *bio)
	451	{
	452	struct se_task *task = bio->bi_private;
42bf829e	453	struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
c66ac9db NB	454
	455	bio_free(bio, ib_dev->ibd_bio_set);
	456	}
	457
dbbf3e94 CH	458	static struct bio *
dbbf3e94 CH	459	iblock_get_bio(struct se_task *task, sector_t lba, u32 sg_num)
c66ac9db	460	{
42bf829e	461	struct iblock_dev *ib_dev = task->task_se_cmd->se_dev->dev_ptr;
dbbf3e94	462	struct iblock_req *ib_req = IBLOCK_REQ(task);
c66ac9db NB	463	struct bio *bio;
c66ac9db NB	464
5c55125f CH	465	/*
	466	* Only allocate as many vector entries as the bio code allows us to,
	467	* we'll loop later on until we have handled the whole request.
	468	*/
	469	if (sg_num > BIO_MAX_PAGES)
	470	sg_num = BIO_MAX_PAGES;
	471
c66ac9db	472	bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
6708bb27 AG	473	if (!bio) {
6708bb27 AG	474	pr_err("Unable to allocate memory for bio\n");
c66ac9db NB	475	return NULL;
	476	}
	477
6708bb27 AG	478	pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:"
	479	" %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set);
	480	pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size);
c66ac9db NB	481
c66ac9db NB	482	bio->bi_bdev = ib_dev->ibd_bd;
5951146d	483	bio->bi_private = task;
c66ac9db NB	484	bio->bi_destructor = iblock_bio_destructor;
	485	bio->bi_end_io = &iblock_bio_done;
	486	bio->bi_sector = lba;
	487	atomic_inc(&ib_req->ib_bio_cnt);
	488
6708bb27 AG	489	pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector);
6708bb27 AG	490	pr_debug("Set ib_req->ib_bio_cnt: %d\n",
c66ac9db NB	491	atomic_read(&ib_req->ib_bio_cnt));
	492	return bio;
	493	}
	494
dbbf3e94	495	static int iblock_do_task(struct se_task *task)
c66ac9db NB	496	{
c66ac9db NB	497	struct se_cmd *cmd = task->task_se_cmd;
5951146d	498	struct se_device *dev = cmd->se_dev;
dbbf3e94 CH	499	struct bio *bio;
dbbf3e94 CH	500	struct bio_list list;
c66ac9db	501	struct scatterlist *sg;
6708bb27	502	u32 i, sg_num = task->task_sg_nents;
c66ac9db	503	sector_t block_lba;
dbbf3e94 CH	504	struct blk_plug plug;
	505	int rw;
	506
	507	if (task->task_data_direction == DMA_TO_DEVICE) {
	508	/*
	509	* Force data to disk if we pretend to not have a volatile
	510	* write cache, or the initiator set the Force Unit Access bit.
	511	*/
	512	if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 \|\|
	513	(dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
2d3a4b51	514	(cmd->se_cmd_flags & SCF_FUA)))
dbbf3e94 CH	515	rw = WRITE_FUA;
	516	else
	517	rw = WRITE;
	518	} else {
	519	rw = READ;
	520	}
	521
c66ac9db NB	522	/*
	523	* Do starting conversion up from non 512-byte blocksize with
	524	* struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
	525	*/
e3d6f909	526	if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
c66ac9db	527	block_lba = (task->task_lba << 3);
e3d6f909	528	else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
c66ac9db	529	block_lba = (task->task_lba << 2);
e3d6f909	530	else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
c66ac9db	531	block_lba = (task->task_lba << 1);
e3d6f909	532	else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
c66ac9db NB	533	block_lba = task->task_lba;
c66ac9db NB	534	else {
6708bb27	535	pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
e3d6f909	536	" %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
03e98c9e NB	537	cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
03e98c9e NB	538	return -ENOSYS;
c66ac9db NB	539	}
c66ac9db NB	540
dbbf3e94	541	bio = iblock_get_bio(task, block_lba, sg_num);
03e98c9e NB	542	if (!bio) {
	543	cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
	544	return -ENOMEM;
	545	}
dbbf3e94 CH	546
	547	bio_list_init(&list);
	548	bio_list_add(&list, bio);
c66ac9db	549
6708bb27	550	for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
dbbf3e94 CH	551	/*
	552	* XXX: if the length the device accepts is shorter than the
	553	* length of the S/G list entry this will cause and
	554	* endless loop. Better hope no driver uses huge pages.
	555	*/
	556	while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
	557	!= sg->length) {
	558	bio = iblock_get_bio(task, block_lba, sg_num);
6708bb27	559	if (!bio)
c66ac9db	560	goto fail;
dbbf3e94	561	bio_list_add(&list, bio);
c66ac9db	562	}
dbbf3e94	563
c66ac9db NB	564	/* Always in 512 byte units for Linux/Block */
	565	block_lba += sg->length >> IBLOCK_LBA_SHIFT;
	566	sg_num--;
c66ac9db NB	567	}
c66ac9db NB	568
dbbf3e94 CH	569	blk_start_plug(&plug);
	570	while ((bio = bio_list_pop(&list)))
	571	submit_bio(rw, bio);
	572	blk_finish_plug(&plug);
	573
03e98c9e	574	return 0;
dbbf3e94	575
c66ac9db	576	fail:
dbbf3e94	577	while ((bio = bio_list_pop(&list)))
c66ac9db	578	bio_put(bio);
03e98c9e NB	579	cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
03e98c9e NB	580	return -ENOMEM;
c66ac9db NB	581	}
c66ac9db NB	582
c66ac9db NB	583	static u32 iblock_get_device_rev(struct se_device *dev)
	584	{
	585	return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
	586	}
	587
	588	static u32 iblock_get_device_type(struct se_device *dev)
	589	{
	590	return TYPE_DISK;
	591	}
	592
	593	static sector_t iblock_get_blocks(struct se_device *dev)
	594	{
	595	struct iblock_dev *ibd = dev->dev_ptr;
	596	struct block_device *bd = ibd->ibd_bd;
	597	struct request_queue *q = bdev_get_queue(bd);
	598
	599	return iblock_emulate_read_cap_with_block_size(dev, bd, q);
	600	}
	601
	602	static void iblock_bio_done(struct bio *bio, int err)
	603	{
	604	struct se_task *task = bio->bi_private;
	605	struct iblock_req *ibr = IBLOCK_REQ(task);
dbbf3e94	606
c66ac9db NB	607	/*
	608	* Set -EIO if !BIO_UPTODATE and the passed is still err=0
	609	*/
6708bb27	610	if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
c66ac9db NB	611	err = -EIO;
	612
	613	if (err != 0) {
6708bb27	614	pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
c66ac9db NB	615	" err: %d\n", bio, err);
	616	/*
	617	* Bump the ib_bio_err_cnt and release bio.
	618	*/
	619	atomic_inc(&ibr->ib_bio_err_cnt);
	620	smp_mb__after_atomic_inc();
c66ac9db	621	}
dbbf3e94	622
c66ac9db	623	bio_put(bio);
dbbf3e94	624
6708bb27	625	if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
c66ac9db	626	return;
dbbf3e94 CH	627
	628	pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
	629	task, bio, task->task_lba,
	630	(unsigned long long)bio->bi_sector, err);
	631
	632	transport_complete_task(task, !atomic_read(&ibr->ib_bio_err_cnt));
c66ac9db NB	633	}
	634
	635	static struct se_subsystem_api iblock_template = {
	636	.name = "iblock",
	637	.owner = THIS_MODULE,
	638	.transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
f55918fa CH	639	.write_cache_emulated = 1,
f55918fa CH	640	.fua_write_emulated = 1,
c66ac9db NB	641	.attach_hba = iblock_attach_hba,
	642	.detach_hba = iblock_detach_hba,
	643	.allocate_virtdevice = iblock_allocate_virtdevice,
	644	.create_virtdevice = iblock_create_virtdevice,
	645	.free_device = iblock_free_device,
c66ac9db NB	646	.alloc_task = iblock_alloc_task,
	647	.do_task = iblock_do_task,
	648	.do_discard = iblock_do_discard,
	649	.do_sync_cache = iblock_emulate_sync_cache,
	650	.free_task = iblock_free_task,
	651	.check_configfs_dev_params = iblock_check_configfs_dev_params,
	652	.set_configfs_dev_params = iblock_set_configfs_dev_params,
	653	.show_configfs_dev_params = iblock_show_configfs_dev_params,
c66ac9db NB	654	.get_device_rev = iblock_get_device_rev,
	655	.get_device_type = iblock_get_device_type,
	656	.get_blocks = iblock_get_blocks,
	657	};
	658
	659	static int __init iblock_module_init(void)
	660	{
	661	return transport_subsystem_register(&iblock_template);
	662	}
	663
	664	static void iblock_module_exit(void)
	665	{
	666	transport_subsystem_release(&iblock_template);
	667	}
	668
	669	MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
	670	MODULE_AUTHOR("nab@Linux-iSCSI.org");
	671	MODULE_LICENSE("GPL");
	672
	673	module_init(iblock_module_init);
	674	module_exit(iblock_module_exit);