// 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 <nab@kernel.org>
*
******************************************************************************/
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/timer.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/blk-integrity.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/bio.h>
#include <linux/file.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/pr.h>
#include <scsi/scsi_proto.h>
#include <scsi/scsi_common.h>
#include <asm/unaligned.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include "target_core_iblock.h"
#include "target_core_pr.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 file *bdev_file;
struct block_device *bd;
struct blk_integrity *bi;
blk_mode_t mode = BLK_OPEN_READ;
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);
if (!ib_dev->ibd_readonly)
mode |= BLK_OPEN_WRITE;
else
dev->dev_flags |= DF_READ_ONLY;
bdev_file = bdev_file_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev,
NULL);
if (IS_ERR(bdev_file)) {
ret = PTR_ERR(bdev_file);
goto out_free_bioset;
}
ib_dev->ibd_bdev_file = bdev_file;
ib_dev->ibd_bd = bd = file_bdev(bdev_file);
q = bdev_get_queue(bd);
dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q),
SECTOR_SIZE,
dev->dev_attrib.hw_block_size);
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:
fput(ib_dev->ibd_bdev_file);
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_bdev_file)
fput(ib_dev->ibd_bdev_file);
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, blk_status_t blk_status)
{
struct iblock_req *ibr = cmd->priv;
u8 status;
if (!refcount_dec_and_test(&ibr->pending))
return;
if (blk_status == BLK_STS_RESV_CONFLICT)
status = SAM_STAT_RESERVATION_CONFLICT;
else 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;
blk_status_t blk_status = bio->bi_status;
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, blk_status);
}
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);
}
/* 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 = bio_integrity_bytes(bi, bio_sectors(bio));
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);
/*
* Set bits to indicate WRITE_ODIRECT so we are not throttled
* by WBT.
*/
opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
/*
* Force writethrough using REQ_FUA if a volatile write cache
* is not enabled, or if initiator set the Force Unit Access bit.
*/
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, BLK_STS_OK);
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, BLK_STS_OK);
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 sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key,
u64 sa_key, u8 type, bool aptpl)
{
struct se_device *dev = cmd->se_dev;
struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
struct block_device *bdev = ib_dev->ibd_bd;
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
int ret;
if (!ops) {
pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
switch (sa) {
case PRO_REGISTER:
case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
if (!ops->pr_register) {
pr_err("block device does not support pr_register.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
/* The block layer pr ops always enables aptpl */
if (!aptpl)
pr_info("APTPL not set by initiator, but will be used.\n");
ret = ops->pr_register(bdev, key, sa_key,
sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY);
break;
case PRO_RESERVE:
if (!ops->pr_reserve) {
pr_err("block_device does not support pr_reserve.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0);
break;
case PRO_CLEAR:
if (!ops->pr_clear) {
pr_err("block_device does not support pr_clear.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
ret = ops->pr_clear(bdev, key);
break;
case PRO_PREEMPT:
case PRO_PREEMPT_AND_ABORT:
if (!ops->pr_clear) {
pr_err("block_device does not support pr_preempt.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
ret = ops->pr_preempt(bdev, key, sa_key,
scsi_pr_type_to_block(type),
sa == PRO_PREEMPT_AND_ABORT);
break;
case PRO_RELEASE:
if (!ops->pr_clear) {
pr_err("block_device does not support pr_pclear.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type));
break;
default:
pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa);
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
if (!ret)
return TCM_NO_SENSE;
else if (ret == PR_STS_RESERVATION_CONFLICT)
return TCM_RESERVATION_CONFLICT;
else
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
static void iblock_pr_report_caps(unsigned char *param_data)
{
u16 len = 8;
put_unaligned_be16(len, ¶m_data[0]);
/*
* When using the pr_ops passthrough method we only support exporting
* the device through one target port because from the backend module
* level we can't see the target port config. As a result we only
* support registration directly from the I_T nexus the cmd is sent
* through and do not set ATP_C here.
*
* The block layer pr_ops do not support passing in initiators so
* we don't set SIP_C here.
*/
/* PTPL_C: Persistence across Target Power Loss bit */
param_data[2] |= 0x01;
/*
* We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
* set the TMV: Task Mask Valid bit.
*/
param_data[3] |= 0x80;
/*
* Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
*/
param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */
/*
* PTPL_A: Persistence across Target Power Loss Active bit. The block
* layer pr ops always enables this so report it active.
*/
param_data[3] |= 0x01;
/*
* Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37.
*/
param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
}
static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd,
unsigned char *param_data)
{
struct se_device *dev = cmd->se_dev;
struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
struct block_device *bdev = ib_dev->ibd_bd;
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
int i, len, paths, data_offset;
struct pr_keys *keys;
sense_reason_t ret;
if (!ops) {
pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
if (!ops->pr_read_keys) {
pr_err("Block device does not support read_keys.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
/*
* We don't know what's under us, but dm-multipath will register every
* path with the same key, so start off with enough space for 16 paths.
* which is not a lot of memory and should normally be enough.
*/
paths = 16;
retry:
len = 8 * paths;
keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL);
if (!keys)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
keys->num_keys = paths;
if (!ops->pr_read_keys(bdev, keys)) {
if (keys->num_keys > paths) {
kfree(keys);
paths *= 2;
goto retry;
}
} else {
ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
goto free_keys;
}
ret = TCM_NO_SENSE;
put_unaligned_be32(keys->generation, ¶m_data[0]);
if (!keys->num_keys) {
put_unaligned_be32(0, ¶m_data[4]);
goto free_keys;
}
put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]);
data_offset = 8;
for (i = 0; i < keys->num_keys; i++) {
if (data_offset + 8 > cmd->data_length)
break;
put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]);
data_offset += 8;
}
free_keys:
kfree(keys);
return ret;
}
static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd,
unsigned char *param_data)
{
struct se_device *dev = cmd->se_dev;
struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
struct block_device *bdev = ib_dev->ibd_bd;
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_held_reservation rsv = { };
if (!ops) {
pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
if (!ops->pr_read_reservation) {
pr_err("Block device does not support read_keys.\n");
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
if (ops->pr_read_reservation(bdev, &rsv))
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
put_unaligned_be32(rsv.generation, ¶m_data[0]);
if (!block_pr_type_to_scsi(rsv.type)) {
put_unaligned_be32(0, ¶m_data[4]);
return TCM_NO_SENSE;
}
put_unaligned_be32(16, ¶m_data[4]);
if (cmd->data_length < 16)
return TCM_NO_SENSE;
put_unaligned_be64(rsv.key, ¶m_data[8]);
if (cmd->data_length < 22)
return TCM_NO_SENSE;
param_data[21] = block_pr_type_to_scsi(rsv.type);
return TCM_NO_SENSE;
}
static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa,
unsigned char *param_data)
{
sense_reason_t ret = TCM_NO_SENSE;
switch (sa) {
case PRI_REPORT_CAPABILITIES:
iblock_pr_report_caps(param_data);
break;
case PRI_READ_KEYS:
ret = iblock_pr_read_keys(cmd, param_data);
break;
case PRI_READ_RESERVATION:
ret = iblock_pr_read_reservation(cmd, param_data);
break;
default:
pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa);
return TCM_UNSUPPORTED_SCSI_OPCODE;
}
return ret;
}
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 exec_cmd_ops iblock_exec_cmd_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,
.execute_pr_out = iblock_execute_pr_out,
.execute_pr_in = iblock_execute_pr_in,
};
static sense_reason_t
iblock_parse_cdb(struct se_cmd *cmd)
{
return sbc_parse_cdb(cmd, &iblock_exec_cmd_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",
.transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR,
.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);
