--- /dev/null
+/*******************************************************************************
+ * Filename: target_core_iblock.c
+ *
+ * This file contains the Storage Engine <-> Linux BlockIO transport
+ * specific functions.
+ *
+ * (c) Copyright 2003-2013 Datera, Inc.
+ *
+ * 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 <asm/unaligned.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+#include <target/target_core_backend_configfs.h>
+
+#include "target_core_iblock.h"
+
+#define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
+#define IBLOCK_BIO_POOL_SIZE 128
+
+static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
+{
+ return container_of(dev, struct iblock_dev, dev);
+}
+
+
+static struct se_subsystem_api iblock_template;
+
+/* 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 struct se_device *iblock_alloc_device(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->dev;
+}
+
+static int iblock_configure_device(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct request_queue *q;
+ struct block_device *bd = NULL;
+ struct blk_integrity *bi;
+ fmode_t mode;
+ int ret = -ENOMEM;
+
+ if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
+ pr_err("Missing udev_path= parameters for IBLOCK\n");
+ return -EINVAL;
+ }
+
+ ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
+ if (!ib_dev->ibd_bio_set) {
+ pr_err("IBLOCK: Unable to create bioset\n");
+ goto out;
+ }
+
+ pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
+ ib_dev->ibd_udev_path);
+
+ mode = FMODE_READ|FMODE_EXCL;
+ if (!ib_dev->ibd_readonly)
+ mode |= FMODE_WRITE;
+
+ bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
+ if (IS_ERR(bd)) {
+ ret = PTR_ERR(bd);
+ goto out_free_bioset;
+ }
+ ib_dev->ibd_bd = bd;
+
+ q = bdev_get_queue(bd);
+
+ dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
+ dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q);
+ dev->dev_attrib.hw_queue_depth = q->nr_requests;
+
+ /*
+ * 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->dev_attrib.max_unmap_lba_count =
+ q->limits.max_discard_sectors;
+
+ /*
+ * Currently hardcoded to 1 in Linux/SCSI code..
+ */
+ dev->dev_attrib.max_unmap_block_desc_count = 1;
+ dev->dev_attrib.unmap_granularity =
+ q->limits.discard_granularity >> 9;
+ dev->dev_attrib.unmap_granularity_alignment =
+ q->limits.discard_alignment;
+
+ pr_debug("IBLOCK: BLOCK Discard support available,"
+ " disabled by default\n");
+ }
+ /*
+ * Enable write same emulation for IBLOCK and use 0xFFFF as
+ * the smaller WRITE_SAME(10) only has a two-byte block count.
+ */
+ dev->dev_attrib.max_write_same_len = 0xFFFF;
+
+ if (blk_queue_nonrot(q))
+ dev->dev_attrib.is_nonrot = 1;
+
+ bi = bdev_get_integrity(bd);
+ if (bi) {
+ struct bio_set *bs = ib_dev->ibd_bio_set;
+
+ if (!strcmp(bi->name, "T10-DIF-TYPE3-IP") ||
+ !strcmp(bi->name, "T10-DIF-TYPE1-IP")) {
+ pr_err("IBLOCK export of blk_integrity: %s not"
+ " supported\n", bi->name);
+ ret = -ENOSYS;
+ goto out_blkdev_put;
+ }
+
+ if (!strcmp(bi->name, "T10-DIF-TYPE3-CRC")) {
+ dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
+ } else if (!strcmp(bi->name, "T10-DIF-TYPE1-CRC")) {
+ dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
+ }
+
+ if (dev->dev_attrib.pi_prot_type) {
+ if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
+ pr_err("Unable to allocate bioset for PI\n");
+ ret = -ENOMEM;
+ goto out_blkdev_put;
+ }
+ pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
+ bs->bio_integrity_pool);
+ }
+ dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
+ }
+
+ return 0;
+
+out_blkdev_put:
+ blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
+out_free_bioset:
+ bioset_free(ib_dev->ibd_bio_set);
+ ib_dev->ibd_bio_set = NULL;
+out:
+ return ret;
+}
+
+static void iblock_free_device(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+
+ 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 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->dev_attrib.block_size)
+ return blocks_long;
+
+ switch (block_size) {
+ case 4096:
+ switch (dev->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->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->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->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_complete_cmd(struct se_cmd *cmd)
+{
+ struct iblock_req *ibr = cmd->priv;
+ u8 status;
+
+ if (!atomic_dec_and_test(&ibr->pending))
+ return;
+
+ if (atomic_read(&ibr->ib_bio_err_cnt))
+ status = SAM_STAT_CHECK_CONDITION;
+ else
+ status = SAM_STAT_GOOD;
+
+ target_complete_cmd(cmd, status);
+ kfree(ibr);
+}
+
+static void iblock_bio_done(struct bio *bio, int err)
+{
+ struct se_cmd *cmd = bio->bi_private;
+ struct iblock_req *ibr = cmd->priv;
+
+ /*
+ * 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();
+ }
+
+ bio_put(bio);
+
+ iblock_complete_cmd(cmd);
+}
+
+static struct bio *
+iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
+ 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;
+ }
+
+ bio->bi_bdev = ib_dev->ibd_bd;
+ bio->bi_private = cmd;
+ bio->bi_end_io = &iblock_bio_done;
+ bio->bi_iter.bi_sector = lba;
+
+ return bio;
+}
+
+static void iblock_submit_bios(struct bio_list *list, int rw)
+{
+ struct blk_plug plug;
+ struct bio *bio;
+
+ blk_start_plug(&plug);
+ while ((bio = bio_list_pop(list)))
+ submit_bio(rw, bio);
+ blk_finish_plug(&plug);
+}
+
+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) {
+ if (err)
+ target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
+ else
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+ }
+
+ bio_put(bio);
+}
+
+/*
+ * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
+ * always flush the whole cache.
+ */
+static sense_reason_t
+iblock_execute_sync_cache(struct se_cmd *cmd)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
+ 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)
+ target_complete_cmd(cmd, SAM_STAT_GOOD);
+
+ 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);
+ return 0;
+}
+
+static sense_reason_t
+iblock_do_unmap(struct se_cmd *cmd, void *priv,
+ sector_t lba, sector_t nolb)
+{
+ struct block_device *bdev = priv;
+ int ret;
+
+ ret = blkdev_issue_discard(bdev, lba, nolb, GFP_KERNEL, 0);
+ if (ret < 0) {
+ pr_err("blkdev_issue_discard() failed: %d\n", ret);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ return 0;
+}
+
+static sense_reason_t
+iblock_execute_unmap(struct se_cmd *cmd)
+{
+ struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
+
+ return sbc_execute_unmap(cmd, iblock_do_unmap, bdev);
+}
+
+static sense_reason_t
+iblock_execute_write_same_unmap(struct se_cmd *cmd)
+{
+ struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
+ sector_t lba = cmd->t_task_lba;
+ sector_t nolb = sbc_get_write_same_sectors(cmd);
+ sense_reason_t ret;
+
+ ret = iblock_do_unmap(cmd, bdev, lba, nolb);
+ if (ret)
+ return ret;
+
+ target_complete_cmd(cmd, GOOD);
+ return 0;
+}
+
+static sense_reason_t
+iblock_execute_write_same(struct se_cmd *cmd)
+{
+ struct iblock_req *ibr;
+ struct scatterlist *sg;
+ struct bio *bio;
+ struct bio_list list;
+ sector_t block_lba = cmd->t_task_lba;
+ sector_t sectors = sbc_get_write_same_sectors(cmd);
+
+ if (cmd->prot_op) {
+ pr_err("WRITE_SAME: Protection information with IBLOCK"
+ " backends not supported\n");
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+ sg = &cmd->t_data_sg[0];
+
+ if (cmd->t_data_nents > 1 ||
+ sg->length != cmd->se_dev->dev_attrib.block_size) {
+ pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
+ " block_size: %u\n", cmd->t_data_nents, sg->length,
+ cmd->se_dev->dev_attrib.block_size);
+ return TCM_INVALID_CDB_FIELD;
+ }
+
+ ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
+ if (!ibr)
+ goto fail;
+ cmd->priv = ibr;
+
+ bio = iblock_get_bio(cmd, block_lba, 1);
+ if (!bio)
+ goto fail_free_ibr;
+
+ bio_list_init(&list);
+ bio_list_add(&list, bio);
+
+ atomic_set(&ibr->pending, 1);
+
+ while (sectors) {
+ while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
+ != sg->length) {
+
+ bio = iblock_get_bio(cmd, block_lba, 1);
+ if (!bio)
+ goto fail_put_bios;
+
+ atomic_inc(&ibr->pending);
+ bio_list_add(&list, bio);
+ }
+
+ /* Always in 512 byte units for Linux/Block */
+ block_lba += sg->length >> IBLOCK_LBA_SHIFT;
+ sectors -= 1;
+ }
+
+ iblock_submit_bios(&list, WRITE);
+ return 0;
+
+fail_put_bios:
+ while ((bio = bio_list_pop(&list)))
+ bio_put(bio);
+fail_free_ibr:
+ kfree(ibr);
+fail:
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+}
+
+enum {
+ Opt_udev_path, Opt_readonly, Opt_force, Opt_err
+};
+
+static match_table_t tokens = {
+ {Opt_udev_path, "udev_path=%s"},
+ {Opt_readonly, "readonly=%d"},
+ {Opt_force, "force=%d"},
+ {Opt_err, NULL}
+};
+
+static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
+ const char *page, ssize_t count)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ char *orig, *ptr, *arg_p, *opts;
+ substring_t args[MAX_OPT_ARGS];
+ int ret = 0, token;
+ unsigned long tmp_readonly;
+
+ 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;
+ }
+ if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
+ SE_UDEV_PATH_LEN) == 0) {
+ ret = -EINVAL;
+ break;
+ }
+ pr_debug("IBLOCK: Referencing UDEV path: %s\n",
+ ib_dev->ibd_udev_path);
+ ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
+ break;
+ case Opt_readonly:
+ arg_p = match_strdup(&args[0]);
+ if (!arg_p) {
+ ret = -ENOMEM;
+ break;
+ }
+ ret = kstrtoul(arg_p, 0, &tmp_readonly);
+ kfree(arg_p);
+ if (ret < 0) {
+ pr_err("kstrtoul() failed for"
+ " readonly=\n");
+ goto out;
+ }
+ ib_dev->ibd_readonly = tmp_readonly;
+ pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
+ break;
+ case Opt_force:
+ break;
+ default:
+ break;
+ }
+ }
+
+out:
+ kfree(orig);
+ return (!ret) ? count : ret;
+}
+
+static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+ char buf[BDEVNAME_SIZE];
+ ssize_t bl = 0;
+
+ if (bd)
+ bl += sprintf(b + bl, "iBlock device: %s",
+ bdevname(bd, buf));
+ if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
+ bl += sprintf(b + bl, " UDEV PATH: %s",
+ ib_dev->ibd_udev_path);
+ bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
+
+ 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 == ib_dev) ?
+ "CLAIMED: IBLOCK" : "CLAIMED: OS");
+ } else {
+ bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
+ }
+
+ return bl;
+}
+
+static int
+iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio)
+{
+ struct se_device *dev = cmd->se_dev;
+ struct blk_integrity *bi;
+ struct bio_integrity_payload *bip;
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct scatterlist *sg;
+ int i, rc;
+
+ bi = bdev_get_integrity(ib_dev->ibd_bd);
+ if (!bi) {
+ pr_err("Unable to locate bio_integrity\n");
+ return -ENODEV;
+ }
+
+ bip = bio_integrity_alloc(bio, GFP_NOIO, cmd->t_prot_nents);
+ if (!bip) {
+ pr_err("Unable to allocate bio_integrity_payload\n");
+ return -ENOMEM;
+ }
+
+ bip->bip_iter.bi_size = (cmd->data_length / dev->dev_attrib.block_size) *
+ dev->prot_length;
+ bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
+
+ pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
+ (unsigned long long)bip->bip_iter.bi_sector);
+
+ for_each_sg(cmd->t_prot_sg, sg, cmd->t_prot_nents, i) {
+
+ rc = bio_integrity_add_page(bio, sg_page(sg), sg->length,
+ sg->offset);
+ if (rc != sg->length) {
+ pr_err("bio_integrity_add_page() failed; %d\n", rc);
+ return -ENOMEM;
+ }
+
+ pr_debug("Added bio integrity page: %p length: %d offset; %d\n",
+ sg_page(sg), sg->length, sg->offset);
+ }
+
+ return 0;
+}
+
+static sense_reason_t
+iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+ enum dma_data_direction data_direction)
+{
+ struct se_device *dev = cmd->se_dev;
+ struct iblock_req *ibr;
+ struct bio *bio, *bio_start;
+ struct bio_list list;
+ struct scatterlist *sg;
+ u32 sg_num = sgl_nents;
+ sector_t block_lba;
+ unsigned bio_cnt;
+ int rw = 0;
+ int i;
+
+ if (data_direction == DMA_TO_DEVICE) {
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd);
+ /*
+ * Force writethrough using WRITE_FUA if a volatile write cache
+ * is not enabled, or if initiator set the Force Unit Access bit.
+ */
+ if (q->flush_flags & REQ_FUA) {
+ if (cmd->se_cmd_flags & SCF_FUA)
+ rw = WRITE_FUA;
+ else if (!(q->flush_flags & REQ_FLUSH))
+ rw = WRITE_FUA;
+ else
+ rw = WRITE;
+ } else {
+ rw = WRITE;
+ }
+ } else {
+ rw = READ;
+ }
+
+ /*
+ * Convert the blocksize advertised to the initiator to the 512 byte
+ * units unconditionally used by the Linux block layer.
+ */
+ if (dev->dev_attrib.block_size == 4096)
+ block_lba = (cmd->t_task_lba << 3);
+ else if (dev->dev_attrib.block_size == 2048)
+ block_lba = (cmd->t_task_lba << 2);
+ else if (dev->dev_attrib.block_size == 1024)
+ block_lba = (cmd->t_task_lba << 1);
+ else if (dev->dev_attrib.block_size == 512)
+ block_lba = cmd->t_task_lba;
+ else {
+ pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
+ " %u\n", dev->dev_attrib.block_size);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
+
+ ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
+ if (!ibr)
+ goto fail;
+ cmd->priv = ibr;
+
+ if (!sgl_nents) {
+ atomic_set(&ibr->pending, 1);
+ iblock_complete_cmd(cmd);
+ return 0;
+ }
+
+ bio = iblock_get_bio(cmd, block_lba, sgl_nents);
+ if (!bio)
+ goto fail_free_ibr;
+
+ bio_start = bio;
+ bio_list_init(&list);
+ bio_list_add(&list, bio);
+
+ atomic_set(&ibr->pending, 2);
+ bio_cnt = 1;
+
+ for_each_sg(sgl, sg, sgl_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) {
+ if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
+ iblock_submit_bios(&list, rw);
+ bio_cnt = 0;
+ }
+
+ bio = iblock_get_bio(cmd, block_lba, sg_num);
+ if (!bio)
+ goto fail_put_bios;
+
+ atomic_inc(&ibr->pending);
+ bio_list_add(&list, bio);
+ bio_cnt++;
+ }
+
+ /* Always in 512 byte units for Linux/Block */
+ block_lba += sg->length >> IBLOCK_LBA_SHIFT;
+ sg_num--;
+ }
+
+ if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
+ int rc = iblock_alloc_bip(cmd, bio_start);
+ if (rc)
+ goto fail_put_bios;
+ }
+
+ iblock_submit_bios(&list, rw);
+ iblock_complete_cmd(cmd);
+ return 0;
+
+fail_put_bios:
+ while ((bio = bio_list_pop(&list)))
+ bio_put(bio);
+fail_free_ibr:
+ kfree(ibr);
+fail:
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+}
+
+static sector_t iblock_get_blocks(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+ struct request_queue *q = bdev_get_queue(bd);
+
+ return iblock_emulate_read_cap_with_block_size(dev, bd, q);
+}
+
+static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+ int ret;
+
+ ret = bdev_alignment_offset(bd);
+ if (ret == -1)
+ return 0;
+
+ /* convert offset-bytes to offset-lbas */
+ return ret / bdev_logical_block_size(bd);
+}
+
+static unsigned int iblock_get_lbppbe(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+ int logs_per_phys = bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
+
+ return ilog2(logs_per_phys);
+}
+
+static unsigned int iblock_get_io_min(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+
+ return bdev_io_min(bd);
+}
+
+static unsigned int iblock_get_io_opt(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+
+ return bdev_io_opt(bd);
+}
+
+static struct sbc_ops iblock_sbc_ops = {
+ .execute_rw = iblock_execute_rw,
+ .execute_sync_cache = iblock_execute_sync_cache,
+ .execute_write_same = iblock_execute_write_same,
+ .execute_write_same_unmap = iblock_execute_write_same_unmap,
+ .execute_unmap = iblock_execute_unmap,
+};
+
+static sense_reason_t
+iblock_parse_cdb(struct se_cmd *cmd)
+{
+ return sbc_parse_cdb(cmd, &iblock_sbc_ops);
+}
+
+static bool iblock_get_write_cache(struct se_device *dev)
+{
+ struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
+ struct block_device *bd = ib_dev->ibd_bd;
+ struct request_queue *q = bdev_get_queue(bd);
+
+ return q->flush_flags & REQ_FLUSH;
+}
+
+DEF_TB_DEFAULT_ATTRIBS(iblock);
+
+static struct configfs_attribute *iblock_backend_dev_attrs[] = {
+ &iblock_dev_attrib_emulate_model_alias.attr,
+ &iblock_dev_attrib_emulate_dpo.attr,
+ &iblock_dev_attrib_emulate_fua_write.attr,
+ &iblock_dev_attrib_emulate_fua_read.attr,
+ &iblock_dev_attrib_emulate_write_cache.attr,
+ &iblock_dev_attrib_emulate_ua_intlck_ctrl.attr,
+ &iblock_dev_attrib_emulate_tas.attr,
+ &iblock_dev_attrib_emulate_tpu.attr,
+ &iblock_dev_attrib_emulate_tpws.attr,
+ &iblock_dev_attrib_emulate_caw.attr,
+ &iblock_dev_attrib_emulate_3pc.attr,
+ &iblock_dev_attrib_pi_prot_type.attr,
+ &iblock_dev_attrib_hw_pi_prot_type.attr,
+ &iblock_dev_attrib_pi_prot_format.attr,
+ &iblock_dev_attrib_enforce_pr_isids.attr,
+ &iblock_dev_attrib_is_nonrot.attr,
+ &iblock_dev_attrib_emulate_rest_reord.attr,
+ &iblock_dev_attrib_force_pr_aptpl.attr,
+ &iblock_dev_attrib_hw_block_size.attr,
+ &iblock_dev_attrib_block_size.attr,
+ &iblock_dev_attrib_hw_max_sectors.attr,
+ &iblock_dev_attrib_optimal_sectors.attr,
+ &iblock_dev_attrib_hw_queue_depth.attr,
+ &iblock_dev_attrib_queue_depth.attr,
+ &iblock_dev_attrib_max_unmap_lba_count.attr,
+ &iblock_dev_attrib_max_unmap_block_desc_count.attr,
+ &iblock_dev_attrib_unmap_granularity.attr,
+ &iblock_dev_attrib_unmap_granularity_alignment.attr,
+ &iblock_dev_attrib_max_write_same_len.attr,
+ NULL,
+};
+
+static struct se_subsystem_api iblock_template = {
+ .name = "iblock",
+ .inquiry_prod = "IBLOCK",
+ .inquiry_rev = IBLOCK_VERSION,
+ .owner = THIS_MODULE,
+ .attach_hba = iblock_attach_hba,
+ .detach_hba = iblock_detach_hba,
+ .alloc_device = iblock_alloc_device,
+ .configure_device = iblock_configure_device,
+ .free_device = iblock_free_device,
+ .parse_cdb = iblock_parse_cdb,
+ .set_configfs_dev_params = iblock_set_configfs_dev_params,
+ .show_configfs_dev_params = iblock_show_configfs_dev_params,
+ .get_device_type = sbc_get_device_type,
+ .get_blocks = iblock_get_blocks,
+ .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
+ .get_lbppbe = iblock_get_lbppbe,
+ .get_io_min = iblock_get_io_min,
+ .get_io_opt = iblock_get_io_opt,
+ .get_write_cache = iblock_get_write_cache,
+};
+
+static int __init iblock_module_init(void)
+{
+ struct target_backend_cits *tbc = &iblock_template.tb_cits;
+
+ target_core_setup_sub_cits(&iblock_template);
+ tbc->tb_dev_attrib_cit.ct_attrs = iblock_backend_dev_attrs;
+
+ return transport_subsystem_register(&iblock_template);
+}
+
+static void __exit 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);
Code Review / kvmfornfv.git / blobdiff