linux/drivers/target/target_core_pscsi.c
Ming Lei 84c8590646 target: avoid accessing .bi_vcnt directly
When the bio is full, bio_add_pc_page() will return zero,
so use this information tell when the bio is full.

Also replace access to .bi_vcnt for pr_debug() with bio_segments().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-22 08:57:55 -07:00

1138 lines
28 KiB
C

/*******************************************************************************
* 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>
*
* 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/blkdev.h>
#include <linux/blk_types.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/genhd.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"
#define ISPRINT(a) ((a >= ' ') && (a <= '~'))
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 void pscsi_req_done(struct request *, int);
/* 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)
return;
memset(cdb, 0, MAX_COMMAND_SIZE);
cdb[0] = MODE_SENSE;
cdb[4] = 0x0c; /* 12 bytes */
ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
HZ, 1, NULL);
if (ret)
goto out_free;
/*
* If MODE_SENSE still returns zero, set the default value to 1024.
*/
sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
if (!sdev->sector_size)
sdev->sector_size = 1024;
out_free:
kfree(buf);
}
static void
pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
{
unsigned char *buf;
if (sdev->inquiry_len < INQUIRY_LEN)
return;
buf = sdev->inquiry;
if (!buf)
return;
/*
* Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
*/
memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
}
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 */
cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
INQUIRY_VPD_SERIAL_LEN, NULL, 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 */
cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
NULL, HZ, 1, NULL);
if (ret)
goto out;
page_len = (buf[2] << 8) | buf[3];
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 = sd->sector_size;
dev->dev_attrib.hw_max_sectors =
min_t(int, 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);
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 using supplied udev_path
*/
bd = blkdev_get_by_path(dev->udev_path,
FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
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, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
scsi_device_put(sd);
return ret;
}
pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%llu\n",
phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
return 0;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static int pscsi_create_type_rom(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;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static int pscsi_create_type_other(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;
spin_unlock_irq(sh->host_lock);
ret = pscsi_add_device_to_list(dev, sd);
if (ret)
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 calling pscsi_add_device_to_list() to register
* struct scsi_device with target_core_mod.
*/
switch (sd->type) {
case TYPE_DISK:
ret = pscsi_create_type_disk(dev, sd);
break;
case TYPE_ROM:
ret = pscsi_create_type_rom(dev, sd);
break;
default:
ret = pscsi_create_type_other(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)
{
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 from pscsi_create_type_disk()
*/
if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
blkdev_put(pdv->pdv_bd,
FMODE_WRITE|FMODE_READ|FMODE_EXCL);
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);
if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
scsi_device_put(sd);
pdv->pdv_sd = NULL;
}
call_rcu(&dev->rcu_head, pscsi_dev_call_rcu);
}
static void pscsi_transport_complete(struct se_cmd *cmd, struct scatterlist *sg,
unsigned char *sense_buffer)
{
struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
struct scsi_device *sd = pdv->pdv_sd;
int result;
struct pscsi_plugin_task *pt = cmd->priv;
unsigned char *cdb;
/*
* Special case for REPORT_LUNs handling where pscsi_plugin_task has
* not been allocated because TCM is handling the emulation directly.
*/
if (!pt)
return;
cdb = &pt->pscsi_cdb[0];
result = pt->pscsi_result;
/*
* 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)) &&
(status_byte(result) << 1) == 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 */
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)) &&
(status_byte(result) << 1) == SAM_STAT_GOOD) {
unsigned char *buf;
u16 bdl;
u32 blocksize;
buf = sg_virt(&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 = (buf[6] << 8) | (buf[7]);
if (!bdl)
goto after_mode_select;
if (cdb[0] == MODE_SELECT)
blocksize = (buf[9] << 16) | (buf[10] << 8) |
(buf[11]);
else
blocksize = (buf[13] << 16) | (buf[14] << 8) |
(buf[15]);
sd->sector_size = blocksize;
}
after_mode_select:
if (sense_buffer && (status_byte(result) & CHECK_CONDITION)) {
memcpy(sense_buffer, pt->pscsi_sense, TRANSPORT_SENSE_BUFFER);
cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
}
}
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;
int i;
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, " ");
bl += sprintf(b + bl, "Vendor: ");
for (i = 0; i < 8; i++) {
if (ISPRINT(sd->vendor[i])) /* printable character? */
bl += sprintf(b + bl, "%c", sd->vendor[i]);
else
bl += sprintf(b + bl, " ");
}
bl += sprintf(b + bl, " Model: ");
for (i = 0; i < 16; i++) {
if (ISPRINT(sd->model[i])) /* printable character ? */
bl += sprintf(b + bl, "%c", sd->model[i]);
else
bl += sprintf(b + bl, " ");
}
bl += sprintf(b + bl, " Rev: ");
for (i = 0; i < 4; i++) {
if (ISPRINT(sd->rev[i])) /* printable character ? */
bl += sprintf(b + bl, "%c", sd->rev[i]);
else
bl += sprintf(b + bl, " ");
}
bl += sprintf(b + bl, "\n");
}
return bl;
}
static void pscsi_bi_endio(struct bio *bio)
{
bio_put(bio);
}
static inline struct bio *pscsi_get_bio(int nr_vecs)
{
struct bio *bio;
/*
* Use bio_malloc() following the comment in for bio -> struct request
* in block/blk-core.c:blk_make_request()
*/
bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
if (!bio) {
pr_err("PSCSI: bio_kmalloc() failed\n");
return NULL;
}
bio->bi_end_io = pscsi_bi_endio;
return 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) {
nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
nr_pages -= nr_vecs;
/*
* Calls bio_kmalloc() and sets bio->bi_end_io()
*/
bio = pscsi_get_bio(nr_vecs);
if (!bio)
goto fail;
if (rw)
bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
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;
}
/*
* Clear the pointer so that another bio will
* be allocated with pscsi_get_bio() above.
*/
bio = NULL;
}
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:
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 pscsi_plugin_task *pt;
struct request *req;
sense_reason_t ret;
/*
* Dynamically alloc cdb space, since it may be larger than
* TCM_MAX_COMMAND_SIZE
*/
pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
if (!pt) {
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
cmd->priv = pt;
memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
scsi_command_size(cmd->t_task_cdb));
req = blk_get_request(pdv->pdv_sd->request_queue,
(cmd->data_direction == DMA_TO_DEVICE),
GFP_KERNEL);
if (IS_ERR(req)) {
pr_err("PSCSI: blk_get_request() failed\n");
ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
goto fail;
}
blk_rq_set_block_pc(req);
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;
req->cmd_len = scsi_command_size(pt->pscsi_cdb);
req->cmd = &pt->pscsi_cdb[0];
req->sense = &pt->pscsi_sense[0];
req->sense_len = 0;
if (pdv->pdv_sd->type == TYPE_DISK)
req->timeout = PS_TIMEOUT_DISK;
else
req->timeout = PS_TIMEOUT_OTHER;
req->retries = PS_RETRY;
blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
(cmd->sam_task_attr == TCM_HEAD_TAG),
pscsi_req_done);
return 0;
fail_put_request:
blk_put_request(req);
fail:
kfree(pt);
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 && pdv->pdv_bd->bd_part)
return pdv->pdv_bd->bd_part->nr_sects;
dump_stack();
return 0;
}
static void pscsi_req_done(struct request *req, int uptodate)
{
struct se_cmd *cmd = req->end_io_data;
struct pscsi_plugin_task *pt = cmd->priv;
pt->pscsi_result = req->errors;
pt->pscsi_resid = req->resid_len;
cmd->scsi_status = status_byte(pt->pscsi_result) << 1;
if (cmd->scsi_status) {
pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
pt->pscsi_result);
}
switch (host_byte(pt->pscsi_result)) {
case DID_OK:
target_complete_cmd(cmd, cmd->scsi_status);
break;
default:
pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
pt->pscsi_result);
target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
break;
}
__blk_put_request(req->q, req);
kfree(pt);
}
static const struct target_backend_ops pscsi_ops = {
.name = "pscsi",
.owner = THIS_MODULE,
.transport_flags = TRANSPORT_FLAG_PASSTHROUGH,
.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,
.free_device = pscsi_free_device,
.transport_complete = pscsi_transport_complete,
.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);