diff options
author | 2015-08-04 12:17:53 -0700 | |
---|---|---|
committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/target/target_core_iblock.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/target/target_core_iblock.c')
-rw-r--r-- | kernel/drivers/target/target_core_iblock.c | 944 |
1 files changed, 944 insertions, 0 deletions
diff --git a/kernel/drivers/target/target_core_iblock.c b/kernel/drivers/target/target_core_iblock.c new file mode 100644 index 000000000..8c9656837 --- /dev/null +++ b/kernel/drivers/target/target_core_iblock.c @@ -0,0 +1,944 @@ +/******************************************************************************* + * 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); |