linux/drivers/target/target_core_pscsi.c
Christoph Hellwig 2736e8eeb0 block: use the holder as indication for exclusive opens
The current interface for exclusive opens is rather confusing as it
requires both the FMODE_EXCL flag and a holder.  Remove the need to pass
FMODE_EXCL and just key off the exclusive open off a non-NULL holder.

For blkdev_put this requires adding the holder argument, which provides
better debug checking that only the holder actually releases the hold,
but at the same time allows removing the now superfluous mode argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>		[btrfs]
Acked-by: Jack Wang <jinpu.wang@ionos.com>		[rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-12 08:04:04 -06:00

1070 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*******************************************************************************
* Filename: target_core_pscsi.c
*
* This file contains the generic target mode <-> Linux SCSI subsystem plugin.
*
* (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/blkdev.h>
#include <linux/blk_types.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/cdrom.h>
#include <linux/ratelimit.h>
#include <linux/module.h>
#include <asm/unaligned.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include "target_core_alua.h"
#include "target_core_internal.h"
#include "target_core_pscsi.h"
static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
{
return container_of(dev, struct pscsi_dev_virt, dev);
}
static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
static enum rq_end_io_ret pscsi_req_done(struct request *, blk_status_t);
/* pscsi_attach_hba():
*
* pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
* from the passed SCSI Host ID.
*/
static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
{
struct pscsi_hba_virt *phv;
phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
if (!phv) {
pr_err("Unable to allocate struct pscsi_hba_virt\n");
return -ENOMEM;
}
phv->phv_host_id = host_id;
phv->phv_mode = PHV_VIRTUAL_HOST_ID;
hba->hba_ptr = phv;
pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
" Generic Target Core Stack %s\n", hba->hba_id,
PSCSI_VERSION, TARGET_CORE_VERSION);
pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
hba->hba_id);
return 0;
}
static void pscsi_detach_hba(struct se_hba *hba)
{
struct pscsi_hba_virt *phv = hba->hba_ptr;
struct Scsi_Host *scsi_host = phv->phv_lld_host;
if (scsi_host) {
scsi_host_put(scsi_host);
pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
" Generic Target Core\n", hba->hba_id,
(scsi_host->hostt->name) ? (scsi_host->hostt->name) :
"Unknown");
} else
pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
" from Generic Target Core\n", hba->hba_id);
kfree(phv);
hba->hba_ptr = NULL;
}
static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
{
struct pscsi_hba_virt *phv = hba->hba_ptr;
struct Scsi_Host *sh = phv->phv_lld_host;
/*
* Release the struct Scsi_Host
*/
if (!mode_flag) {
if (!sh)
return 0;
phv->phv_lld_host = NULL;
phv->phv_mode = PHV_VIRTUAL_HOST_ID;
pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
" %s\n", hba->hba_id, (sh->hostt->name) ?
(sh->hostt->name) : "Unknown");
scsi_host_put(sh);
return 0;
}
/*
* Otherwise, locate struct Scsi_Host from the original passed
* pSCSI Host ID and enable for phba mode
*/
sh = scsi_host_lookup(phv->phv_host_id);
if (!sh) {
pr_err("pSCSI: Unable to locate SCSI Host for"
" phv_host_id: %d\n", phv->phv_host_id);
return -EINVAL;
}
phv->phv_lld_host = sh;
phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
return 1;
}
static void pscsi_tape_read_blocksize(struct se_device *dev,
struct scsi_device *sdev)
{
unsigned char cdb[MAX_COMMAND_SIZE], *buf;
int ret;
buf = kzalloc(12, GFP_KERNEL);
if (!buf)
goto out_free;
memset(cdb, 0, MAX_COMMAND_SIZE);
cdb[0] = MODE_SENSE;
cdb[4] = 0x0c; /* 12 bytes */
ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf, 12, HZ, 1, NULL);
if (ret)
goto out_free;
/*
* If MODE_SENSE still returns zero, set the default value to 1024.
*/
sdev->sector_size = get_unaligned_be24(&buf[9]);
out_free:
if (!sdev->sector_size)
sdev->sector_size = 1024;
kfree(buf);
}
static void
pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
{
if (sdev->inquiry_len < INQUIRY_LEN)
return;
/*
* Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
*/
BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
snprintf(wwn->vendor, sizeof(wwn->vendor),
"%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
snprintf(wwn->model, sizeof(wwn->model),
"%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
snprintf(wwn->revision, sizeof(wwn->revision),
"%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
}
static int
pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
{
unsigned char cdb[MAX_COMMAND_SIZE], *buf;
int ret;
buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
if (!buf)
return -ENOMEM;
memset(cdb, 0, MAX_COMMAND_SIZE);
cdb[0] = INQUIRY;
cdb[1] = 0x01; /* Query VPD */
cdb[2] = 0x80; /* Unit Serial Number */
put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, &cdb[3]);
ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf,
INQUIRY_VPD_SERIAL_LEN, HZ, 1, NULL);
if (ret)
goto out_free;
snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
kfree(buf);
return 0;
out_free:
kfree(buf);
return -EPERM;
}
static void
pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
struct t10_wwn *wwn)
{
unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
int ident_len, page_len, off = 4, ret;
struct t10_vpd *vpd;
buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
if (!buf)
return;
memset(cdb, 0, MAX_COMMAND_SIZE);
cdb[0] = INQUIRY;
cdb[1] = 0x01; /* Query VPD */
cdb[2] = 0x83; /* Device Identifier */
put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, &cdb[3]);
ret = scsi_execute_cmd(sdev, cdb, REQ_OP_DRV_IN, buf,
INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, HZ, 1, NULL);
if (ret)
goto out;
page_len = get_unaligned_be16(&buf[2]);
while (page_len > 0) {
/* Grab a pointer to the Identification descriptor */
page_83 = &buf[off];
ident_len = page_83[3];
if (!ident_len) {
pr_err("page_83[3]: identifier"
" length zero!\n");
break;
}
pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
if (!vpd) {
pr_err("Unable to allocate memory for"
" struct t10_vpd\n");
goto out;
}
INIT_LIST_HEAD(&vpd->vpd_list);
transport_set_vpd_proto_id(vpd, page_83);
transport_set_vpd_assoc(vpd, page_83);
if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
off += (ident_len + 4);
page_len -= (ident_len + 4);
kfree(vpd);
continue;
}
if (transport_set_vpd_ident(vpd, page_83) < 0) {
off += (ident_len + 4);
page_len -= (ident_len + 4);
kfree(vpd);
continue;
}
list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
off += (ident_len + 4);
page_len -= (ident_len + 4);
}
out:
kfree(buf);
}
static int pscsi_add_device_to_list(struct se_device *dev,
struct scsi_device *sd)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct request_queue *q = sd->request_queue;
pdv->pdv_sd = sd;
if (!sd->queue_depth) {
sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
pr_err("Set broken SCSI Device %d:%d:%llu"
" queue_depth to %d\n", sd->channel, sd->id,
sd->lun, sd->queue_depth);
}
dev->dev_attrib.hw_block_size =
min_not_zero((int)sd->sector_size, 512);
dev->dev_attrib.hw_max_sectors =
min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
dev->dev_attrib.hw_queue_depth = sd->queue_depth;
/*
* Setup our standard INQUIRY info into se_dev->t10_wwn
*/
pscsi_set_inquiry_info(sd, &dev->t10_wwn);
/*
* Locate VPD WWN Information used for various purposes within
* the Storage Engine.
*/
if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
/*
* If VPD Unit Serial returned GOOD status, try
* VPD Device Identification page (0x83).
*/
pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
}
/*
* For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
*/
if (sd->type == TYPE_TAPE) {
pscsi_tape_read_blocksize(dev, sd);
dev->dev_attrib.hw_block_size = sd->sector_size;
}
return 0;
}
static struct se_device *pscsi_alloc_device(struct se_hba *hba,
const char *name)
{
struct pscsi_dev_virt *pdv;
pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
if (!pdv) {
pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
return NULL;
}
pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
return &pdv->dev;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
__releases(sh->host_lock)
{
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct Scsi_Host *sh = sd->host;
struct block_device *bd;
int ret;
if (scsi_device_get(sd)) {
pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
sh->host_no, sd->channel, sd->id, sd->lun);
spin_unlock_irq(sh->host_lock);
return -EIO;
}
spin_unlock_irq(sh->host_lock);
/*
* Claim exclusive struct block_device access to struct scsi_device
* for TYPE_DISK and TYPE_ZBC using supplied udev_path
*/
bd = blkdev_get_by_path(dev->udev_path, FMODE_WRITE | FMODE_READ, pdv,
NULL);
if (IS_ERR(bd)) {
pr_err("pSCSI: blkdev_get_by_path() failed\n");
scsi_device_put(sd);
return PTR_ERR(bd);
}
pdv->pdv_bd = bd;
ret = pscsi_add_device_to_list(dev, sd);
if (ret) {
blkdev_put(pdv->pdv_bd, pdv);
scsi_device_put(sd);
return ret;
}
pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
sh->host_no, sd->channel, sd->id, sd->lun);
return 0;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
__releases(sh->host_lock)
{
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
struct Scsi_Host *sh = sd->host;
int ret;
if (scsi_device_get(sd)) {
pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
sh->host_no, sd->channel, sd->id, sd->lun);
spin_unlock_irq(sh->host_lock);
return -EIO;
}
spin_unlock_irq(sh->host_lock);
ret = pscsi_add_device_to_list(dev, sd);
if (ret) {
scsi_device_put(sd);
return ret;
}
pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
sd->channel, sd->id, sd->lun);
return 0;
}
static int pscsi_configure_device(struct se_device *dev)
{
struct se_hba *hba = dev->se_hba;
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct scsi_device *sd;
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
struct Scsi_Host *sh = phv->phv_lld_host;
int legacy_mode_enable = 0;
int ret;
if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
!(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
!(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
pr_err("Missing scsi_channel_id=, scsi_target_id= and"
" scsi_lun_id= parameters\n");
return -EINVAL;
}
/*
* If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
* struct Scsi_Host we will need to bring the TCM/pSCSI object online
*/
if (!sh) {
if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
pr_err("pSCSI: Unable to locate struct"
" Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
return -ENODEV;
}
/*
* For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
* reference, we enforce that udev_path has been set
*/
if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
pr_err("pSCSI: udev_path attribute has not"
" been set before ENABLE=1\n");
return -EINVAL;
}
/*
* If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
* use the original TCM hba ID to reference Linux/SCSI Host No
* and enable for PHV_LLD_SCSI_HOST_NO mode.
*/
if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
if (hba->dev_count) {
pr_err("pSCSI: Unable to set hba_mode"
" with active devices\n");
return -EEXIST;
}
if (pscsi_pmode_enable_hba(hba, 1) != 1)
return -ENODEV;
legacy_mode_enable = 1;
hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
sh = phv->phv_lld_host;
} else {
sh = scsi_host_lookup(pdv->pdv_host_id);
if (!sh) {
pr_err("pSCSI: Unable to locate"
" pdv_host_id: %d\n", pdv->pdv_host_id);
return -EINVAL;
}
pdv->pdv_lld_host = sh;
}
} else {
if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
" struct Scsi_Host exists\n");
return -EEXIST;
}
}
spin_lock_irq(sh->host_lock);
list_for_each_entry(sd, &sh->__devices, siblings) {
if ((pdv->pdv_channel_id != sd->channel) ||
(pdv->pdv_target_id != sd->id) ||
(pdv->pdv_lun_id != sd->lun))
continue;
/*
* Functions will release the held struct scsi_host->host_lock
* before calling pscsi_add_device_to_list() to register
* struct scsi_device with target_core_mod.
*/
switch (sd->type) {
case TYPE_DISK:
case TYPE_ZBC:
ret = pscsi_create_type_disk(dev, sd);
break;
default:
ret = pscsi_create_type_nondisk(dev, sd);
break;
}
if (ret) {
if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
scsi_host_put(sh);
else if (legacy_mode_enable) {
pscsi_pmode_enable_hba(hba, 0);
hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
}
pdv->pdv_sd = NULL;
return ret;
}
return 0;
}
spin_unlock_irq(sh->host_lock);
pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id);
if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
scsi_host_put(sh);
else if (legacy_mode_enable) {
pscsi_pmode_enable_hba(hba, 0);
hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
}
return -ENODEV;
}
static void pscsi_dev_call_rcu(struct rcu_head *p)
{
struct se_device *dev = container_of(p, struct se_device, rcu_head);
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
kfree(pdv);
}
static void pscsi_free_device(struct se_device *dev)
{
call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
}
static void pscsi_destroy_device(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
struct scsi_device *sd = pdv->pdv_sd;
if (sd) {
/*
* Release exclusive pSCSI internal struct block_device claim for
* struct scsi_device with TYPE_DISK or TYPE_ZBC
* from pscsi_create_type_disk()
*/
if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
pdv->pdv_bd) {
blkdev_put(pdv->pdv_bd, pdv);
pdv->pdv_bd = NULL;
}
/*
* For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
* to struct Scsi_Host now.
*/
if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
(phv->phv_lld_host != NULL))
scsi_host_put(phv->phv_lld_host);
else if (pdv->pdv_lld_host)
scsi_host_put(pdv->pdv_lld_host);
scsi_device_put(sd);
pdv->pdv_sd = NULL;
}
}
static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
unsigned char *req_sense, int valid_data)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
struct scsi_device *sd = pdv->pdv_sd;
unsigned char *cdb = cmd->priv;
/*
* Special case for REPORT_LUNs which is emulated and not passed on.
*/
if (!cdb)
return;
/*
* Hack to make sure that Write-Protect modepage is set if R/O mode is
* forced.
*/
if (!cmd->data_length)
goto after_mode_sense;
if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
scsi_status == SAM_STAT_GOOD) {
bool read_only = target_lun_is_rdonly(cmd);
if (read_only) {
unsigned char *buf;
buf = transport_kmap_data_sg(cmd);
if (!buf) {
; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
} else {
if (cdb[0] == MODE_SENSE_10) {
if (!(buf[3] & 0x80))
buf[3] |= 0x80;
} else {
if (!(buf[2] & 0x80))
buf[2] |= 0x80;
}
transport_kunmap_data_sg(cmd);
}
}
}
after_mode_sense:
if (sd->type != TYPE_TAPE || !cmd->data_length)
goto after_mode_select;
/*
* Hack to correctly obtain the initiator requested blocksize for
* TYPE_TAPE. Since this value is dependent upon each tape media,
* struct scsi_device->sector_size will not contain the correct value
* by default, so we go ahead and set it so
* TRANSPORT(dev)->get_blockdev() returns the correct value to the
* storage engine.
*/
if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
scsi_status == SAM_STAT_GOOD) {
unsigned char *buf;
u16 bdl;
u32 blocksize;
buf = sg_virt(&cmd->t_data_sg[0]);
if (!buf) {
pr_err("Unable to get buf for scatterlist\n");
goto after_mode_select;
}
if (cdb[0] == MODE_SELECT)
bdl = buf[3];
else
bdl = get_unaligned_be16(&buf[6]);
if (!bdl)
goto after_mode_select;
if (cdb[0] == MODE_SELECT)
blocksize = get_unaligned_be24(&buf[9]);
else
blocksize = get_unaligned_be24(&buf[13]);
sd->sector_size = blocksize;
}
after_mode_select:
if (scsi_status == SAM_STAT_CHECK_CONDITION) {
transport_copy_sense_to_cmd(cmd, req_sense);
/*
* check for TAPE device reads with
* FM/EOM/ILI set, so that we can get data
* back despite framework assumption that a
* check condition means there is no data
*/
if (sd->type == TYPE_TAPE && valid_data &&
cmd->data_direction == DMA_FROM_DEVICE) {
/*
* is sense data valid, fixed format,
* and have FM, EOM, or ILI set?
*/
if (req_sense[0] == 0xf0 && /* valid, fixed format */
req_sense[2] & 0xe0 && /* FM, EOM, or ILI */
(req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
}
}
}
}
enum {
Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
Opt_scsi_lun_id, Opt_err
};
static match_table_t tokens = {
{Opt_scsi_host_id, "scsi_host_id=%d"},
{Opt_scsi_channel_id, "scsi_channel_id=%d"},
{Opt_scsi_target_id, "scsi_target_id=%d"},
{Opt_scsi_lun_id, "scsi_lun_id=%d"},
{Opt_err, NULL}
};
static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
const char *page, ssize_t count)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
char *orig, *ptr, *opts;
substring_t args[MAX_OPT_ARGS];
int ret = 0, arg, token;
opts = kstrdup(page, GFP_KERNEL);
if (!opts)
return -ENOMEM;
orig = opts;
while ((ptr = strsep(&opts, ",\n")) != NULL) {
if (!*ptr)
continue;
token = match_token(ptr, tokens, args);
switch (token) {
case Opt_scsi_host_id:
if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
pr_err("PSCSI[%d]: Unable to accept"
" scsi_host_id while phv_mode =="
" PHV_LLD_SCSI_HOST_NO\n",
phv->phv_host_id);
ret = -EINVAL;
goto out;
}
ret = match_int(args, &arg);
if (ret)
goto out;
pdv->pdv_host_id = arg;
pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
" %d\n", phv->phv_host_id, pdv->pdv_host_id);
pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
break;
case Opt_scsi_channel_id:
ret = match_int(args, &arg);
if (ret)
goto out;
pdv->pdv_channel_id = arg;
pr_debug("PSCSI[%d]: Referencing SCSI Channel"
" ID: %d\n", phv->phv_host_id,
pdv->pdv_channel_id);
pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
break;
case Opt_scsi_target_id:
ret = match_int(args, &arg);
if (ret)
goto out;
pdv->pdv_target_id = arg;
pr_debug("PSCSI[%d]: Referencing SCSI Target"
" ID: %d\n", phv->phv_host_id,
pdv->pdv_target_id);
pdv->pdv_flags |= PDF_HAS_TARGET_ID;
break;
case Opt_scsi_lun_id:
ret = match_int(args, &arg);
if (ret)
goto out;
pdv->pdv_lun_id = arg;
pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
" %d\n", phv->phv_host_id, pdv->pdv_lun_id);
pdv->pdv_flags |= PDF_HAS_LUN_ID;
break;
default:
break;
}
}
out:
kfree(orig);
return (!ret) ? count : ret;
}
static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
{
struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct scsi_device *sd = pdv->pdv_sd;
unsigned char host_id[16];
ssize_t bl;
if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
snprintf(host_id, 16, "%d", pdv->pdv_host_id);
else
snprintf(host_id, 16, "PHBA Mode");
bl = sprintf(b, "SCSI Device Bus Location:"
" Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
host_id);
if (sd) {
bl += sprintf(b + bl, " Vendor: %."
__stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
bl += sprintf(b + bl, " Model: %."
__stringify(INQUIRY_MODEL_LEN) "s", sd->model);
bl += sprintf(b + bl, " Rev: %."
__stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
}
return bl;
}
static void pscsi_bi_endio(struct bio *bio)
{
bio_uninit(bio);
kfree(bio);
}
static sense_reason_t
pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
struct request *req)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
struct bio *bio = NULL;
struct page *page;
struct scatterlist *sg;
u32 data_len = cmd->data_length, i, len, bytes, off;
int nr_pages = (cmd->data_length + sgl[0].offset +
PAGE_SIZE - 1) >> PAGE_SHIFT;
int nr_vecs = 0, rc;
int rw = (cmd->data_direction == DMA_TO_DEVICE);
BUG_ON(!cmd->data_length);
pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
for_each_sg(sgl, sg, sgl_nents, i) {
page = sg_page(sg);
off = sg->offset;
len = sg->length;
pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
page, len, off);
/*
* We only have one page of data in each sg element,
* we can not cross a page boundary.
*/
if (off + len > PAGE_SIZE)
goto fail;
if (len > 0 && data_len > 0) {
bytes = min_t(unsigned int, len, PAGE_SIZE - off);
bytes = min(bytes, data_len);
if (!bio) {
new_bio:
nr_vecs = bio_max_segs(nr_pages);
bio = bio_kmalloc(nr_vecs, GFP_KERNEL);
if (!bio)
goto fail;
bio_init(bio, NULL, bio->bi_inline_vecs, nr_vecs,
rw ? REQ_OP_WRITE : REQ_OP_READ);
bio->bi_end_io = pscsi_bi_endio;
pr_debug("PSCSI: Allocated bio: %p,"
" dir: %s nr_vecs: %d\n", bio,
(rw) ? "rw" : "r", nr_vecs);
}
pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
" bio: %p page: %p len: %d off: %d\n", i, bio,
page, len, off);
rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
bio, page, bytes, off);
pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
bio_segments(bio), nr_vecs);
if (rc != bytes) {
pr_debug("PSCSI: Reached bio->bi_vcnt max:"
" %d i: %d bio: %p, allocating another"
" bio\n", bio->bi_vcnt, i, bio);
rc = blk_rq_append_bio(req, bio);
if (rc) {
pr_err("pSCSI: failed to append bio\n");
goto fail;
}
goto new_bio;
}
data_len -= bytes;
}
}
if (bio) {
rc = blk_rq_append_bio(req, bio);
if (rc) {
pr_err("pSCSI: failed to append bio\n");
goto fail;
}
}
return 0;
fail:
if (bio)
bio_put(bio);
while (req->bio) {
bio = req->bio;
req->bio = bio->bi_next;
bio_put(bio);
}
req->biotail = NULL;
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
static sense_reason_t
pscsi_parse_cdb(struct se_cmd *cmd)
{
if (cmd->se_cmd_flags & SCF_BIDI)
return TCM_UNSUPPORTED_SCSI_OPCODE;
return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
}
static sense_reason_t
pscsi_execute_cmd(struct se_cmd *cmd)
{
struct scatterlist *sgl = cmd->t_data_sg;
u32 sgl_nents = cmd->t_data_nents;
struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
struct scsi_cmnd *scmd;
struct request *req;
sense_reason_t ret;
req = scsi_alloc_request(pdv->pdv_sd->request_queue,
cmd->data_direction == DMA_TO_DEVICE ?
REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
if (IS_ERR(req))
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
if (sgl) {
ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
if (ret)
goto fail_put_request;
}
req->end_io = pscsi_req_done;
req->end_io_data = cmd;
scmd = blk_mq_rq_to_pdu(req);
scmd->cmd_len = scsi_command_size(cmd->t_task_cdb);
if (scmd->cmd_len > sizeof(scmd->cmnd)) {
ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
goto fail_put_request;
}
memcpy(scmd->cmnd, cmd->t_task_cdb, scmd->cmd_len);
if (pdv->pdv_sd->type == TYPE_DISK ||
pdv->pdv_sd->type == TYPE_ZBC)
req->timeout = PS_TIMEOUT_DISK;
else
req->timeout = PS_TIMEOUT_OTHER;
scmd->allowed = PS_RETRY;
cmd->priv = scmd->cmnd;
blk_execute_rq_nowait(req, cmd->sam_task_attr == TCM_HEAD_TAG);
return 0;
fail_put_request:
blk_mq_free_request(req);
return ret;
}
/* pscsi_get_device_type():
*
*
*/
static u32 pscsi_get_device_type(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
struct scsi_device *sd = pdv->pdv_sd;
return (sd) ? sd->type : TYPE_NO_LUN;
}
static sector_t pscsi_get_blocks(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
if (pdv->pdv_bd)
return bdev_nr_sectors(pdv->pdv_bd);
return 0;
}
static enum rq_end_io_ret pscsi_req_done(struct request *req,
blk_status_t status)
{
struct se_cmd *cmd = req->end_io_data;
struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
enum sam_status scsi_status = scmd->result & 0xff;
int valid_data = cmd->data_length - scmd->resid_len;
u8 *cdb = cmd->priv;
if (scsi_status != SAM_STAT_GOOD) {
pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
" 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
}
pscsi_complete_cmd(cmd, scsi_status, scmd->sense_buffer, valid_data);
switch (host_byte(scmd->result)) {
case DID_OK:
target_complete_cmd_with_length(cmd, scsi_status, valid_data);
break;
default:
pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
" 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
break;
}
blk_mq_free_request(req);
return RQ_END_IO_NONE;
}
static const struct target_backend_ops pscsi_ops = {
.name = "pscsi",
.owner = THIS_MODULE,
.transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
TRANSPORT_FLAG_PASSTHROUGH_ALUA |
TRANSPORT_FLAG_PASSTHROUGH_PGR,
.attach_hba = pscsi_attach_hba,
.detach_hba = pscsi_detach_hba,
.pmode_enable_hba = pscsi_pmode_enable_hba,
.alloc_device = pscsi_alloc_device,
.configure_device = pscsi_configure_device,
.destroy_device = pscsi_destroy_device,
.free_device = pscsi_free_device,
.parse_cdb = pscsi_parse_cdb,
.set_configfs_dev_params = pscsi_set_configfs_dev_params,
.show_configfs_dev_params = pscsi_show_configfs_dev_params,
.get_device_type = pscsi_get_device_type,
.get_blocks = pscsi_get_blocks,
.tb_dev_attrib_attrs = passthrough_attrib_attrs,
};
static int __init pscsi_module_init(void)
{
return transport_backend_register(&pscsi_ops);
}
static void __exit pscsi_module_exit(void)
{
target_backend_unregister(&pscsi_ops);
}
MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
MODULE_AUTHOR("nab@Linux-iSCSI.org");
MODULE_LICENSE("GPL");
module_init(pscsi_module_init);
module_exit(pscsi_module_exit);