From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/target/target_core_iblock.c | 930 ++++++++++++++++++++++++++++++++++++ 1 file changed, 930 insertions(+) create mode 100644 drivers/target/target_core_iblock.c (limited to 'drivers/target/target_core_iblock.c') diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c new file mode 100644 index 000000000..d9266cf55 --- /dev/null +++ b/drivers/target/target_core_iblock.c @@ -0,0 +1,930 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/******************************************************************************* + * 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 + * + ******************************************************************************/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#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 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_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; + } + + ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug), + GFP_KERNEL); + if (!ib_dev->ibd_plug) + goto free_dev; + + pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name); + + return &ib_dev->dev; + +free_dev: + kfree(ib_dev); + return NULL; +} + +static bool iblock_configure_unmap(struct se_device *dev) +{ + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + + return target_configure_unmap_from_queue(&dev->dev_attrib, + ib_dev->ibd_bd); +} + +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; + unsigned int max_write_zeroes_sectors; + int ret; + + if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) { + pr_err("Missing udev_path= parameters for IBLOCK\n"); + return -EINVAL; + } + + ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); + if (ret) { + 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; + else + dev->dev_flags |= DF_READ_ONLY; + + 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; + + /* + * Enable write same emulation for IBLOCK and use 0xFFFF as + * the smaller WRITE_SAME(10) only has a two-byte block count. + */ + max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd); + if (max_write_zeroes_sectors) + dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors; + else + dev->dev_attrib.max_write_same_len = 0xFFFF; + + if (bdev_nonrot(bd)) + 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->profile->name, "T10-DIF-TYPE3-IP") || + !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) { + pr_err("IBLOCK export of blk_integrity: %s not" + " supported\n", bi->profile->name); + ret = -ENOSYS; + goto out_blkdev_put; + } + + if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) { + dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT; + } else if (!strcmp(bi->profile->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_exit(&ib_dev->ibd_bio_set); +out: + return ret; +} + +static void iblock_dev_call_rcu(struct rcu_head *p) +{ + struct se_device *dev = container_of(p, struct se_device, rcu_head); + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + + kfree(ib_dev->ibd_plug); + kfree(ib_dev); +} + +static void iblock_free_device(struct se_device *dev) +{ + call_rcu(&dev->rcu_head, iblock_dev_call_rcu); +} + +static void iblock_destroy_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); + bioset_exit(&ib_dev->ibd_bio_set); +} + +static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev) +{ + struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev); + struct iblock_dev_plug *ib_dev_plug; + + /* + * Each se_device has a per cpu work this can be run from. We + * shouldn't have multiple threads on the same cpu calling this + * at the same time. + */ + ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()]; + if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags)) + return NULL; + + blk_start_plug(&ib_dev_plug->blk_plug); + return &ib_dev_plug->se_plug; +} + +static void iblock_unplug_device(struct se_dev_plug *se_plug) +{ + struct iblock_dev_plug *ib_dev_plug = container_of(se_plug, + struct iblock_dev_plug, se_plug); + + blk_finish_plug(&ib_dev_plug->blk_plug); + clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags); +} + +static sector_t iblock_get_blocks(struct se_device *dev) +{ + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd); + unsigned long long blocks_long = + div_u64(bdev_nr_bytes(ib_dev->ibd_bd), block_size) - 1; + + 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; + break; + 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 (!refcount_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) +{ + struct se_cmd *cmd = bio->bi_private; + struct iblock_req *ibr = cmd->priv; + + if (bio->bi_status) { + pr_err("bio error: %p, err: %d\n", bio, bio->bi_status); + /* + * 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, + blk_opf_t opf) +{ + 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. + */ + bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf, + GFP_NOIO, &ib_dev->ibd_bio_set); + if (!bio) { + pr_err("Unable to allocate memory for bio\n"); + return NULL; + } + + 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) +{ + struct blk_plug plug; + struct bio *bio; + /* + * The block layer handles nested plugs, so just plug/unplug to handle + * fabric drivers that didn't support batching and multi bio cmds. + */ + blk_start_plug(&plug); + while ((bio = bio_list_pop(list))) + submit_bio(bio); + blk_finish_plug(&plug); +} + +static void iblock_end_io_flush(struct bio *bio) +{ + struct se_cmd *cmd = bio->bi_private; + + if (bio->bi_status) + pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status); + + if (cmd) { + if (bio->bi_status) + 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(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH, + GFP_KERNEL); + bio->bi_end_io = iblock_end_io_flush; + if (!immed) + bio->bi_private = cmd; + submit_bio(bio); + return 0; +} + +static sense_reason_t +iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) +{ + struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; + struct se_device *dev = cmd->se_dev; + int ret; + + ret = blkdev_issue_discard(bdev, + target_to_linux_sector(dev, lba), + target_to_linux_sector(dev, nolb), + GFP_KERNEL); + 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_zero_out(struct block_device *bdev, struct se_cmd *cmd) +{ + struct se_device *dev = cmd->se_dev; + struct scatterlist *sg = &cmd->t_data_sg[0]; + unsigned char *buf, *not_zero; + int ret; + + buf = kmap(sg_page(sg)) + sg->offset; + if (!buf) + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + /* + * Fall back to block_execute_write_same() slow-path if + * incoming WRITE_SAME payload does not contain zeros. + */ + not_zero = memchr_inv(buf, 0x00, cmd->data_length); + kunmap(sg_page(sg)); + + if (not_zero) + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + + ret = blkdev_issue_zeroout(bdev, + target_to_linux_sector(dev, cmd->t_task_lba), + target_to_linux_sector(dev, + sbc_get_write_same_sectors(cmd)), + GFP_KERNEL, BLKDEV_ZERO_NOUNMAP); + if (ret) + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + + target_complete_cmd(cmd, SAM_STAT_GOOD); + return 0; +} + +static sense_reason_t +iblock_execute_write_same(struct se_cmd *cmd) +{ + struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd; + struct iblock_req *ibr; + struct scatterlist *sg; + struct bio *bio; + struct bio_list list; + struct se_device *dev = cmd->se_dev; + sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); + sector_t sectors = target_to_linux_sector(dev, + 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; + } + + if (!cmd->t_data_nents) + return TCM_INVALID_CDB_FIELD; + + 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; + } + + if (bdev_write_zeroes_sectors(bdev)) { + if (!iblock_execute_zero_out(bdev, cmd)) + return 0; + } + + ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); + if (!ibr) + goto fail; + cmd->priv = ibr; + + bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE); + if (!bio) + goto fail_free_ibr; + + bio_list_init(&list); + bio_list_add(&list, bio); + + refcount_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, REQ_OP_WRITE); + if (!bio) + goto fail_put_bios; + + refcount_inc(&ibr->pending); + bio_list_add(&list, bio); + } + + /* Always in 512 byte units for Linux/Block */ + block_lba += sg->length >> SECTOR_SHIFT; + sectors -= sg->length >> SECTOR_SHIFT; + } + + iblock_submit_bios(&list); + 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; + ssize_t bl = 0; + + if (bd) + bl += sprintf(b + bl, "iBlock device: %pg", bd); + 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), + "CLAIMED: IBLOCK"); + } 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 sg_mapping_iter *miter) +{ + struct se_device *dev = cmd->se_dev; + struct blk_integrity *bi; + struct bio_integrity_payload *bip; + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + int rc; + size_t resid, len; + + 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, bio_max_segs(cmd->t_prot_nents)); + if (IS_ERR(bip)) { + pr_err("Unable to allocate bio_integrity_payload\n"); + return PTR_ERR(bip); + } + + bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); + /* virtual start sector must be in integrity interval units */ + bip_set_seed(bip, bio->bi_iter.bi_sector >> + (bi->interval_exp - SECTOR_SHIFT)); + + pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size, + (unsigned long long)bip->bip_iter.bi_sector); + + resid = bip->bip_iter.bi_size; + while (resid > 0 && sg_miter_next(miter)) { + + len = min_t(size_t, miter->length, resid); + rc = bio_integrity_add_page(bio, miter->page, len, + offset_in_page(miter->addr)); + if (rc != len) { + pr_err("bio_integrity_add_page() failed; %d\n", rc); + sg_miter_stop(miter); + return -ENOMEM; + } + + pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n", + miter->page, len, offset_in_page(miter->addr)); + + resid -= len; + if (len < miter->length) + miter->consumed -= miter->length - len; + } + sg_miter_stop(miter); + + 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; + sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba); + struct iblock_req *ibr; + struct bio *bio; + struct bio_list list; + struct scatterlist *sg; + u32 sg_num = sgl_nents; + blk_opf_t opf; + unsigned bio_cnt; + int i, rc; + struct sg_mapping_iter prot_miter; + unsigned int miter_dir; + + if (data_direction == DMA_TO_DEVICE) { + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + /* + * Force writethrough using REQ_FUA if a volatile write cache + * is not enabled, or if initiator set the Force Unit Access bit. + */ + opf = REQ_OP_WRITE; + miter_dir = SG_MITER_TO_SG; + if (bdev_fua(ib_dev->ibd_bd)) { + if (cmd->se_cmd_flags & SCF_FUA) + opf |= REQ_FUA; + else if (!bdev_write_cache(ib_dev->ibd_bd)) + opf |= REQ_FUA; + } + } else { + opf = REQ_OP_READ; + miter_dir = SG_MITER_FROM_SG; + } + + ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL); + if (!ibr) + goto fail; + cmd->priv = ibr; + + if (!sgl_nents) { + refcount_set(&ibr->pending, 1); + iblock_complete_cmd(cmd); + return 0; + } + + bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf); + if (!bio) + goto fail_free_ibr; + + bio_list_init(&list); + bio_list_add(&list, bio); + + refcount_set(&ibr->pending, 2); + bio_cnt = 1; + + if (cmd->prot_type && dev->dev_attrib.pi_prot_type) + sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents, + miter_dir); + + 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 (cmd->prot_type && dev->dev_attrib.pi_prot_type) { + rc = iblock_alloc_bip(cmd, bio, &prot_miter); + if (rc) + goto fail_put_bios; + } + + if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) { + iblock_submit_bios(&list); + bio_cnt = 0; + } + + bio = iblock_get_bio(cmd, block_lba, sg_num, opf); + if (!bio) + goto fail_put_bios; + + refcount_inc(&ibr->pending); + bio_list_add(&list, bio); + bio_cnt++; + } + + /* Always in 512 byte units for Linux/Block */ + block_lba += sg->length >> SECTOR_SHIFT; + sg_num--; + } + + if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { + rc = iblock_alloc_bip(cmd, bio, &prot_miter); + if (rc) + goto fail_put_bios; + } + + iblock_submit_bios(&list); + 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_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; + unsigned 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_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) +{ + return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd); +} + +static const struct target_backend_ops iblock_ops = { + .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, + .destroy_device = iblock_destroy_device, + .free_device = iblock_free_device, + .configure_unmap = iblock_configure_unmap, + .plug_device = iblock_plug_device, + .unplug_device = iblock_unplug_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, + .tb_dev_attrib_attrs = sbc_attrib_attrs, +}; + +static int __init iblock_module_init(void) +{ + return transport_backend_register(&iblock_ops); +} + +static void __exit iblock_module_exit(void) +{ + target_backend_unregister(&iblock_ops); +} + +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); -- cgit v1.2.3