linux/drivers/target/target_core_pscsi.c
Nicholas Bellinger 65586d51e0 target: Drop se_device TCQ queue_depth usage from I/O path
Historically, pSCSI devices have been the ones that required target-core
to enforce a per se_device->depth_left.  This patch changes target-core
to no longer (by default) enforce a per se_device->depth_left or sleep in
transport_tcq_window_closed() when we out of queue slots for all backend
export cases.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:42:13 +00:00

1266 lines
32 KiB
C

/*******************************************************************************
* Filename: target_core_pscsi.c
*
* This file contains the generic target mode <-> Linux SCSI subsystem plugin.
*
* Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
* Copyright (c) 2005, 2006, 2007 SBE, Inc.
* Copyright (c) 2007-2010 Rising Tide Systems
* Copyright (c) 2008-2010 Linux-iSCSI.org
*
* 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/file.h>
#include <linux/module.h>
#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.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_pscsi.h"
#define ISPRINT(a) ((a >= ' ') && (a <= '~'))
static struct se_subsystem_api pscsi_template;
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_VIRUTAL_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_MOD_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_VIRUTAL_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 (IS_ERR(sh)) {
pr_err("pSCSI: Unable to locate SCSI Host for"
" phv_host_id: %d\n", phv->phv_host_id);
return PTR_ERR(sh);
}
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_sub_dev->su_dev_flags |= SDF_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 Identifer 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);
}
/* pscsi_add_device_to_list():
*
*
*/
static struct se_device *pscsi_add_device_to_list(
struct se_hba *hba,
struct se_subsystem_dev *se_dev,
struct pscsi_dev_virt *pdv,
struct scsi_device *sd,
int dev_flags)
{
struct se_device *dev;
struct se_dev_limits dev_limits;
struct request_queue *q;
struct queue_limits *limits;
memset(&dev_limits, 0, sizeof(struct se_dev_limits));
if (!sd->queue_depth) {
sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
pr_err("Set broken SCSI Device %d:%d:%d"
" queue_depth to %d\n", sd->channel, sd->id,
sd->lun, sd->queue_depth);
}
/*
* Setup the local scope queue_limits from struct request_queue->limits
* to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
*/
q = sd->request_queue;
limits = &dev_limits.limits;
limits->logical_block_size = sd->sector_size;
limits->max_hw_sectors = min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
limits->max_sectors = min_t(int, sd->host->max_sectors, queue_max_sectors(q));
dev_limits.hw_queue_depth = sd->queue_depth;
dev_limits.queue_depth = sd->queue_depth;
/*
* Setup our standard INQUIRY info into se_dev->t10_wwn
*/
pscsi_set_inquiry_info(sd, &se_dev->t10_wwn);
/*
* Set the pointer pdv->pdv_sd to from passed struct scsi_device,
* which has already been referenced with Linux SCSI code with
* scsi_device_get() in this file's pscsi_create_virtdevice().
*
* The passthrough operations called by the transport_add_device_*
* function below will require this pointer to be set for passthroug
* ops.
*
* For the shutdown case in pscsi_free_device(), this struct
* scsi_device reference is released with Linux SCSI code
* scsi_device_put() and the pdv->pdv_sd cleared.
*/
pdv->pdv_sd = sd;
dev = transport_add_device_to_core_hba(hba, &pscsi_template,
se_dev, dev_flags, pdv,
&dev_limits, NULL, NULL);
if (!dev) {
pdv->pdv_sd = NULL;
return NULL;
}
/*
* Locate VPD WWN Information used for various purposes within
* the Storage Engine.
*/
if (!pscsi_get_inquiry_vpd_serial(sd, &se_dev->t10_wwn)) {
/*
* If VPD Unit Serial returned GOOD status, try
* VPD Device Identification page (0x83).
*/
pscsi_get_inquiry_vpd_device_ident(sd, &se_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 dev;
}
static void *pscsi_allocate_virtdevice(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;
}
pdv->pdv_se_hba = hba;
pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
return pdv;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static struct se_device *pscsi_create_type_disk(
struct scsi_device *sd,
struct pscsi_dev_virt *pdv,
struct se_subsystem_dev *se_dev,
struct se_hba *hba)
__releases(sh->host_lock)
{
struct se_device *dev;
struct pscsi_hba_virt *phv = pdv->pdv_se_hba->hba_ptr;
struct Scsi_Host *sh = sd->host;
struct block_device *bd;
u32 dev_flags = 0;
if (scsi_device_get(sd)) {
pr_err("scsi_device_get() failed for %d:%d:%d:%d\n",
sh->host_no, sd->channel, sd->id, sd->lun);
spin_unlock_irq(sh->host_lock);
return NULL;
}
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(se_dev->se_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 NULL;
}
pdv->pdv_bd = bd;
dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
if (!dev) {
blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
scsi_device_put(sd);
return NULL;
}
pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%d\n",
phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
return dev;
}
/*
* Called with struct Scsi_Host->host_lock called.
*/
static struct se_device *pscsi_create_type_rom(
struct scsi_device *sd,
struct pscsi_dev_virt *pdv,
struct se_subsystem_dev *se_dev,
struct se_hba *hba)
__releases(sh->host_lock)
{
struct se_device *dev;
struct pscsi_hba_virt *phv = pdv->pdv_se_hba->hba_ptr;
struct Scsi_Host *sh = sd->host;
u32 dev_flags = 0;
if (scsi_device_get(sd)) {
pr_err("scsi_device_get() failed for %d:%d:%d:%d\n",
sh->host_no, sd->channel, sd->id, sd->lun);
spin_unlock_irq(sh->host_lock);
return NULL;
}
spin_unlock_irq(sh->host_lock);
dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
if (!dev) {
scsi_device_put(sd);
return NULL;
}
pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%d\n",
phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
sd->channel, sd->id, sd->lun);
return dev;
}
/*
*Called with struct Scsi_Host->host_lock called.
*/
static struct se_device *pscsi_create_type_other(
struct scsi_device *sd,
struct pscsi_dev_virt *pdv,
struct se_subsystem_dev *se_dev,
struct se_hba *hba)
__releases(sh->host_lock)
{
struct se_device *dev;
struct pscsi_hba_virt *phv = pdv->pdv_se_hba->hba_ptr;
struct Scsi_Host *sh = sd->host;
u32 dev_flags = 0;
spin_unlock_irq(sh->host_lock);
dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
if (!dev)
return NULL;
pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%d\n",
phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
sd->channel, sd->id, sd->lun);
return dev;
}
static struct se_device *pscsi_create_virtdevice(
struct se_hba *hba,
struct se_subsystem_dev *se_dev,
void *p)
{
struct pscsi_dev_virt *pdv = p;
struct se_device *dev;
struct scsi_device *sd;
struct pscsi_hba_virt *phv = hba->hba_ptr;
struct Scsi_Host *sh = phv->phv_lld_host;
int legacy_mode_enable = 0;
if (!pdv) {
pr_err("Unable to locate struct pscsi_dev_virt"
" parameter\n");
return ERR_PTR(-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 ERR_PTR(-ENODEV);
}
/*
* For the newer PHV_VIRUTAL_HOST_ID struct scsi_device
* reference, we enforce that udev_path has been set
*/
if (!(se_dev->su_dev_flags & SDF_USING_UDEV_PATH)) {
pr_err("pSCSI: udev_path attribute has not"
" been set before ENABLE=1\n");
return ERR_PTR(-EINVAL);
}
/*
* If no scsi_host_id= was passed for PHV_VIRUTAL_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)) {
spin_lock(&hba->device_lock);
if (!list_empty(&hba->hba_dev_list)) {
pr_err("pSCSI: Unable to set hba_mode"
" with active devices\n");
spin_unlock(&hba->device_lock);
return ERR_PTR(-EEXIST);
}
spin_unlock(&hba->device_lock);
if (pscsi_pmode_enable_hba(hba, 1) != 1)
return ERR_PTR(-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 (IS_ERR(sh)) {
pr_err("pSCSI: Unable to locate"
" pdv_host_id: %d\n", pdv->pdv_host_id);
return ERR_CAST(sh);
}
}
} else {
if (phv->phv_mode == PHV_VIRUTAL_HOST_ID) {
pr_err("pSCSI: PHV_VIRUTAL_HOST_ID set while"
" struct Scsi_Host exists\n");
return ERR_PTR(-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:
dev = pscsi_create_type_disk(sd, pdv, se_dev, hba);
break;
case TYPE_ROM:
dev = pscsi_create_type_rom(sd, pdv, se_dev, hba);
break;
default:
dev = pscsi_create_type_other(sd, pdv, se_dev, hba);
break;
}
if (!dev) {
if (phv->phv_mode == PHV_VIRUTAL_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 ERR_PTR(-ENODEV);
}
return dev;
}
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_VIRUTAL_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 ERR_PTR(-ENODEV);
}
/* pscsi_free_device(): (Part of se_subsystem_api_t template)
*
*
*/
static void pscsi_free_device(void *p)
{
struct pscsi_dev_virt *pdv = p;
struct pscsi_hba_virt *phv = pdv->pdv_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);
if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
scsi_device_put(sd);
pdv->pdv_sd = NULL;
}
kfree(pdv);
}
static inline struct pscsi_plugin_task *PSCSI_TASK(struct se_task *task)
{
return container_of(task, struct pscsi_plugin_task, pscsi_task);
}
/* pscsi_transport_complete():
*
*
*/
static int pscsi_transport_complete(struct se_task *task)
{
struct pscsi_dev_virt *pdv = task->task_se_cmd->se_dev->dev_ptr;
struct scsi_device *sd = pdv->pdv_sd;
int result;
struct pscsi_plugin_task *pt = PSCSI_TASK(task);
unsigned char *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 (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
(status_byte(result) << 1) == SAM_STAT_GOOD) {
if (!task->task_se_cmd->se_deve)
goto after_mode_sense;
if (task->task_se_cmd->se_deve->lun_flags &
TRANSPORT_LUNFLAGS_READ_ONLY) {
unsigned char *buf = transport_kmap_first_data_page(task->task_se_cmd);
if (cdb[0] == MODE_SENSE_10) {
if (!(buf[3] & 0x80))
buf[3] |= 0x80;
} else {
if (!(buf[2] & 0x80))
buf[2] |= 0x80;
}
transport_kunmap_first_data_page(task->task_se_cmd);
}
}
after_mode_sense:
if (sd->type != TYPE_TAPE)
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;
struct scatterlist *sg = task->task_sg;
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 (status_byte(result) & CHECK_CONDITION)
return 1;
return 0;
}
static struct se_task *
pscsi_alloc_task(unsigned char *cdb)
{
struct pscsi_plugin_task *pt;
/*
* Dynamically alloc cdb space, since it may be larger than
* TCM_MAX_COMMAND_SIZE
*/
pt = kzalloc(sizeof(*pt) + scsi_command_size(cdb), GFP_KERNEL);
if (!pt) {
pr_err("Unable to allocate struct pscsi_plugin_task\n");
return NULL;
}
return &pt->pscsi_task;
}
static void pscsi_free_task(struct se_task *task)
{
struct pscsi_plugin_task *pt = PSCSI_TASK(task);
/*
* We do not release the bio(s) here associated with this task, as
* this is handled by bio_put() and pscsi_bi_endio().
*/
kfree(pt);
}
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_hba *hba,
struct se_subsystem_dev *se_dev,
const char *page,
ssize_t count)
{
struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
struct pscsi_hba_virt *phv = 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;
}
match_int(args, &arg);
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:
match_int(args, &arg);
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:
match_int(args, &arg);
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:
match_int(args, &arg);
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_check_configfs_dev_params(
struct se_hba *hba,
struct se_subsystem_dev *se_dev)
{
struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
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;
}
return 0;
}
static ssize_t pscsi_show_configfs_dev_params(struct se_hba *hba,
struct se_subsystem_dev *se_dev,
char *b)
{
struct pscsi_hba_virt *phv = hba->hba_ptr;
struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
struct scsi_device *sd = pdv->pdv_sd;
unsigned char host_id[16];
ssize_t bl;
int i;
if (phv->phv_mode == PHV_VIRUTAL_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, int error)
{
bio_put(bio);
}
static inline struct bio *pscsi_get_bio(int sg_num)
{
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, sg_num);
if (!bio) {
pr_err("PSCSI: bio_kmalloc() failed\n");
return NULL;
}
bio->bi_end_io = pscsi_bi_endio;
return bio;
}
static int pscsi_map_sg(struct se_task *task, struct scatterlist *task_sg,
struct bio **hbio)
{
struct se_cmd *cmd = task->task_se_cmd;
struct pscsi_dev_virt *pdv = task->task_se_cmd->se_dev->dev_ptr;
u32 task_sg_num = task->task_sg_nents;
struct bio *bio = NULL, *tbio = NULL;
struct page *page;
struct scatterlist *sg;
u32 data_len = task->task_size, i, len, bytes, off;
int nr_pages = (task->task_size + task_sg[0].offset +
PAGE_SIZE - 1) >> PAGE_SHIFT;
int nr_vecs = 0, rc;
int rw = (task->task_data_direction == DMA_TO_DEVICE);
*hbio = NULL;
pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
for_each_sg(task_sg, sg, task_sg_num, 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);
while (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->bi_rw |= REQ_WRITE;
pr_debug("PSCSI: Allocated bio: %p,"
" dir: %s nr_vecs: %d\n", bio,
(rw) ? "rw" : "r", nr_vecs);
/*
* Set *hbio pointer to handle the case:
* nr_pages > BIO_MAX_PAGES, where additional
* bios need to be added to complete a given
* struct se_task
*/
if (!*hbio)
*hbio = tbio = bio;
else
tbio = tbio->bi_next = bio;
}
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);
if (rc != bytes)
goto fail;
pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
bio->bi_vcnt, nr_vecs);
if (bio->bi_vcnt > nr_vecs) {
pr_debug("PSCSI: Reached bio->bi_vcnt max:"
" %d i: %d bio: %p, allocating another"
" bio\n", bio->bi_vcnt, i, bio);
/*
* Clear the pointer so that another bio will
* be allocated with pscsi_get_bio() above, the
* current bio has already been set *tbio and
* bio->bi_next.
*/
bio = NULL;
}
page++;
len -= bytes;
data_len -= bytes;
off = 0;
}
}
return task->task_sg_nents;
fail:
while (*hbio) {
bio = *hbio;
*hbio = (*hbio)->bi_next;
bio->bi_next = NULL;
bio_endio(bio, 0); /* XXX: should be error */
}
cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -ENOMEM;
}
static int pscsi_do_task(struct se_task *task)
{
struct se_cmd *cmd = task->task_se_cmd;
struct pscsi_dev_virt *pdv = task->task_se_cmd->se_dev->dev_ptr;
struct pscsi_plugin_task *pt = PSCSI_TASK(task);
struct request *req;
struct bio *hbio;
int ret;
target_get_task_cdb(task, pt->pscsi_cdb);
if (task->task_se_cmd->se_cmd_flags & SCF_SCSI_NON_DATA_CDB) {
req = blk_get_request(pdv->pdv_sd->request_queue,
(task->task_data_direction == DMA_TO_DEVICE),
GFP_KERNEL);
if (!req || IS_ERR(req)) {
pr_err("PSCSI: blk_get_request() failed: %ld\n",
req ? IS_ERR(req) : -ENOMEM);
cmd->scsi_sense_reason =
TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -ENODEV;
}
} else {
BUG_ON(!task->task_size);
/*
* Setup the main struct request for the task->task_sg[] payload
*/
ret = pscsi_map_sg(task, task->task_sg, &hbio);
if (ret < 0) {
cmd->scsi_sense_reason =
TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return ret;
}
req = blk_make_request(pdv->pdv_sd->request_queue, hbio,
GFP_KERNEL);
if (IS_ERR(req)) {
pr_err("pSCSI: blk_make_request() failed\n");
goto fail;
}
}
req->cmd_type = REQ_TYPE_BLOCK_PC;
req->end_io = pscsi_req_done;
req->end_io_data = task;
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,
(task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG),
pscsi_req_done);
return 0;
fail:
while (hbio) {
struct bio *bio = hbio;
hbio = hbio->bi_next;
bio->bi_next = NULL;
bio_endio(bio, 0); /* XXX: should be error */
}
cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -ENOMEM;
}
/* pscsi_get_sense_buffer():
*
*
*/
static unsigned char *pscsi_get_sense_buffer(struct se_task *task)
{
struct pscsi_plugin_task *pt = PSCSI_TASK(task);
return pt->pscsi_sense;
}
/* pscsi_get_device_rev():
*
*
*/
static u32 pscsi_get_device_rev(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = dev->dev_ptr;
struct scsi_device *sd = pdv->pdv_sd;
return (sd->scsi_level - 1) ? sd->scsi_level - 1 : 1;
}
/* pscsi_get_device_type():
*
*
*/
static u32 pscsi_get_device_type(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = dev->dev_ptr;
struct scsi_device *sd = pdv->pdv_sd;
return sd->type;
}
static sector_t pscsi_get_blocks(struct se_device *dev)
{
struct pscsi_dev_virt *pdv = dev->dev_ptr;
if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
return pdv->pdv_bd->bd_part->nr_sects;
dump_stack();
return 0;
}
/* pscsi_handle_SAM_STATUS_failures():
*
*
*/
static inline void pscsi_process_SAM_status(
struct se_task *task,
struct pscsi_plugin_task *pt)
{
task->task_scsi_status = status_byte(pt->pscsi_result);
if (task->task_scsi_status) {
task->task_scsi_status <<= 1;
pr_debug("PSCSI Status Byte exception at task: %p CDB:"
" 0x%02x Result: 0x%08x\n", task, pt->pscsi_cdb[0],
pt->pscsi_result);
}
switch (host_byte(pt->pscsi_result)) {
case DID_OK:
transport_complete_task(task, (!task->task_scsi_status));
break;
default:
pr_debug("PSCSI Host Byte exception at task: %p CDB:"
" 0x%02x Result: 0x%08x\n", task, pt->pscsi_cdb[0],
pt->pscsi_result);
task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
task->task_se_cmd->scsi_sense_reason =
TCM_UNSUPPORTED_SCSI_OPCODE;
transport_complete_task(task, 0);
break;
}
}
static void pscsi_req_done(struct request *req, int uptodate)
{
struct se_task *task = req->end_io_data;
struct pscsi_plugin_task *pt = PSCSI_TASK(task);
pt->pscsi_result = req->errors;
pt->pscsi_resid = req->resid_len;
pscsi_process_SAM_status(task, pt);
__blk_put_request(req->q, req);
}
static struct se_subsystem_api pscsi_template = {
.name = "pscsi",
.owner = THIS_MODULE,
.transport_type = TRANSPORT_PLUGIN_PHBA_PDEV,
.attach_hba = pscsi_attach_hba,
.detach_hba = pscsi_detach_hba,
.pmode_enable_hba = pscsi_pmode_enable_hba,
.allocate_virtdevice = pscsi_allocate_virtdevice,
.create_virtdevice = pscsi_create_virtdevice,
.free_device = pscsi_free_device,
.transport_complete = pscsi_transport_complete,
.alloc_task = pscsi_alloc_task,
.do_task = pscsi_do_task,
.free_task = pscsi_free_task,
.check_configfs_dev_params = pscsi_check_configfs_dev_params,
.set_configfs_dev_params = pscsi_set_configfs_dev_params,
.show_configfs_dev_params = pscsi_show_configfs_dev_params,
.get_sense_buffer = pscsi_get_sense_buffer,
.get_device_rev = pscsi_get_device_rev,
.get_device_type = pscsi_get_device_type,
.get_blocks = pscsi_get_blocks,
};
static int __init pscsi_module_init(void)
{
return transport_subsystem_register(&pscsi_template);
}
static void pscsi_module_exit(void)
{
transport_subsystem_release(&pscsi_template);
}
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);