On 09/23/2010 12:51 AM, Nicholas A. Bellinger wrote:
> From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
>
> This patch adds the PSCSI subsystem plugin for accessing struct scsi_device
> using struct request from upstream Linux/SCSI code. This subsystem plugin
> follows a passthrough design, and does not provide and control CDB emulation
> for the registered struct scsi_device backstores. This subsystem plugin also
> allows the export of both TYPE_DISk and non TYPE_DISK struct scsi_devices.
>
> Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
> ---
> drivers/target/target_core_pscsi.c | 1569 ++++++++++++++++++++++++++++++++++++
> drivers/target/target_core_pscsi.h | 69 ++
> 2 files changed, 1638 insertions(+), 0 deletions(-)
> create mode 100644 drivers/target/target_core_pscsi.c
> create mode 100644 drivers/target/target_core_pscsi.h
>
> diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c
> new file mode 100644
> index 0000000..60f825d
> --- /dev/null
> +++ b/drivers/target/target_core_pscsi.c
> @@ -0,0 +1,1569 @@
> +/*******************************************************************************
> + * 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@xxxxxxxxxx>
> + *
> + * 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/version.h>
> +#include <linux/string.h>
> +#include <linux/timer.h>
> +#include <linux/blkdev.h>
> +#include <linux/blk_types.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/smp_lock.h>
> +#include <linux/genhd.h>
> +#include <linux/cdrom.h>
> +#include <linux/file.h>
> +#include <scsi/scsi.h>
> +#include <scsi/scsi_device.h>
> +#include <scsi/scsi_cmnd.h>
> +#include <scsi/scsi_host.h>
> +
> +#include <target/target_core_base.h>
> +#include <target/target_core_device.h>
> +#include <target/target_core_transport.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);
> +static void __pscsi_get_dev_info(struct pscsi_dev_virt *, char *, int *);
> +
> +/* pscsi_get_sh():
> + *
> + *
> + */
> +static struct Scsi_Host *pscsi_get_sh(u32 host_no)
> +{
> + struct Scsi_Host *sh = NULL;
> +
> + sh = scsi_host_lookup(host_no);
> + if (IS_ERR(sh)) {
> + printk(KERN_ERR "Unable to locate SCSI HBA with Host ID:"
> + " %u\n", host_no);
> + return NULL;
> + }
> +
> + return sh;
> +}
> +
> +/* 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)
> +{
> + int hba_depth;
> + struct pscsi_hba_virt *phv;
> +
> + phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
> + if (!(phv)) {
> + printk(KERN_ERR "Unable to allocate struct pscsi_hba_virt\n");
> + return -1;
> + }
> + phv->phv_host_id = host_id;
> + phv->phv_mode = PHV_VIRUTAL_HOST_ID;
> + hba_depth = PSCSI_VIRTUAL_HBA_DEPTH;
> + atomic_set(&hba->left_queue_depth, hba_depth);
> + atomic_set(&hba->max_queue_depth, hba_depth);
> +
> + hba->hba_ptr = (void *)phv;
> +
> + printk(KERN_INFO "CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
> + " Generic Target Core Stack %s\n", hba->hba_id,
> + PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
> + printk(KERN_INFO "CORE_HBA[%d] - Attached SCSI HBA to Generic"
> + " Target Core with TCQ Depth: %d\n", hba->hba_id,
> + atomic_read(&hba->max_queue_depth));
> +
> + return 0;
> +}
> +
> +/* pscsi_detach_hba(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static int pscsi_detach_hba(struct se_hba *hba)
> +{
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
> + struct Scsi_Host *scsi_host = phv->phv_lld_host;
> +
> + if (scsi_host) {
> + scsi_host_put(scsi_host);
> +
> + printk(KERN_INFO "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
> + printk(KERN_INFO "CORE_HBA[%d] - Detached Virtual SCSI HBA"
> + " from Generic Target Core\n", hba->hba_id);
> +
> + kfree(phv);
> + hba->hba_ptr = NULL;
> +
> + return 0;
> +}
> +
> +static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
> +{
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
> + struct Scsi_Host *sh = phv->phv_lld_host;
> + int hba_depth = PSCSI_VIRTUAL_HBA_DEPTH;
> + /*
> + * Release the struct Scsi_Host
> + */
> + if (!(mode_flag)) {
> + if (!(sh))
> + return 0;
> +
> + phv->phv_lld_host = NULL;
> + phv->phv_mode = PHV_VIRUTAL_HOST_ID;
> + atomic_set(&hba->left_queue_depth, hba_depth);
> + atomic_set(&hba->max_queue_depth, hba_depth);
> +
> + printk(KERN_INFO "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 = pscsi_get_sh(phv->phv_host_id);
> + if (!(sh)) {
> + printk(KERN_ERR "pSCSI: Unable to locate SCSI Host for"
> + " phv_host_id: %d\n", phv->phv_host_id);
> + return -1;
> + }
> + /*
> + * Usually the SCSI LLD will use the hostt->can_queue value to define
> + * its HBA TCQ depth. Some other drivers (like 2.6 megaraid) don't set
> + * this at all and set sh->can_queue at runtime.
> + */
> + hba_depth = (sh->hostt->can_queue > sh->can_queue) ?
> + sh->hostt->can_queue : sh->can_queue;
> +
> + atomic_set(&hba->left_queue_depth, hba_depth);
> + atomic_set(&hba->max_queue_depth, hba_depth);
> +
> + phv->phv_lld_host = sh;
> + phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
> +
> + printk(KERN_INFO "CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
> + hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
> +
> + return 1;
> +}
> +
> +/* 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;
> +
> + /*
> + * Some pseudo SCSI HBAs do not fill in sector_size
> + * correctly. (See ide-scsi.c) So go ahead and setup sane
> + * values.
> + */
> + if (!sd->sector_size) {
> + switch (sd->type) {
> + case TYPE_DISK:
> + sd->sector_size = 512;
> + break;
> + case TYPE_ROM:
> + sd->sector_size = 2048;
> + break;
> + case TYPE_TAPE: /* The Tape may not be in the drive */
> + break;
> + case TYPE_MEDIUM_CHANGER: /* Control CDBs only */
> + break;
> + default:
> + printk(KERN_ERR "Unable to set sector_size for %d\n",
> + sd->type);
> + return NULL;
What about sector-less devices? OSD, Scanners, printers ...
+ default:
+ break;
> + }
> +
> + if (sd->sector_size) {
> + printk(KERN_ERR "Set broken SCSI Device"
> + " %d:%d:%d sector_size to %d\n", sd->channel,
> + sd->id, sd->lun, sd->sector_size);
> + }
> + }
> +
> + if (!sd->queue_depth) {
> + sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
> +
> + printk(KERN_ERR "Set broken SCSI Device %d:%d:%d"
> + " queue_depth to %d\n", sd->channel, sd->id,
> + sd->lun, sd->queue_depth);
> + }
> + /*
> + * 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, (void *)pdv);
> + if (!(dev)) {
> + pdv->pdv_sd = NULL;
> + return NULL;
> + }
> +
> + /*
> + * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
> + */
> + if (sd->type == TYPE_TAPE) {
Just as a future note:
One of the things I'm missing from LIO is the notion of SCSI_TYPE or SCSI
class. So things like this can be done in a plugin manner as per TYPE
Like in the Kernel we have the ULDs for that.
> + unsigned char *buf = NULL, cdb[MAX_COMMAND_SIZE];
> + struct se_cmd *cmd;
> + u32 blocksize;
> +
> + memset(cdb, 0, MAX_COMMAND_SIZE);
> + cdb[0] = MODE_SENSE;
> + cdb[4] = 0x0c; /* 12 bytes */
> +
> + cmd = transport_allocate_passthrough(&cdb[0],
> + DMA_FROM_DEVICE, 0, NULL, 0, 12, dev);
> + if (!(cmd)) {
> + printk(KERN_ERR "Unable to determine blocksize for"
> + " TYPE_TAPE\n");
> + goto out;
> + }
> +
> + if (transport_generic_passthrough(cmd) < 0) {
> + printk(KERN_ERR "Unable to determine blocksize for"
> + " TYPE_TAPE\n");
> + goto out;
> + }
> +
> + buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
> + blocksize = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
> +
> + /*
> + * If MODE_SENSE still returns zero, set the default value
> + * to 1024.
> + */
> + sd->sector_size = blocksize;
> + if (!(sd->sector_size))
> + sd->sector_size = 1024;
> +
> + transport_passthrough_release(cmd);
> + }
> +out:
> + 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)) {
> + printk(KERN_ERR "Unable to allocate memory for struct pscsi_dev_virt\n");
> + return NULL;
> + }
> + pdv->pdv_se_hba = hba;
> +
> + printk(KERN_INFO "PSCSI: Allocated pdv: %p for %s\n", pdv, name);
> + return (void *)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)
> +{
> + struct se_device *dev;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)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)) {
> + printk(KERN_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 = open_bdev_exclusive(se_dev->se_dev_udev_path,
> + FMODE_WRITE|FMODE_READ, pdv);
> + if (!(bd)) {
> + printk("pSCSI: open_bdev_exclusive() 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)) {
> + close_bdev_exclusive(pdv->pdv_bd, FMODE_WRITE|FMODE_READ);
> + scsi_device_put(sd);
> + return NULL;
> + }
> + printk(KERN_INFO "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)
> +{
> + struct se_device *dev;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)pdv->pdv_se_hba->hba_ptr;
> + struct Scsi_Host *sh = sd->host;
> + u32 dev_flags = 0;
> +
> + if (scsi_device_get(sd)) {
> + printk(KERN_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;
> + }
> + printk(KERN_INFO "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)
> +{
> + struct se_device *dev;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)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;
> +
> + printk(KERN_INFO "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 = (struct pscsi_dev_virt *)p;
> + struct se_device *dev;
> + struct scsi_device *sd;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
> + struct Scsi_Host *sh = phv->phv_lld_host;
> + int legacy_mode_enable = 0;
> +
> + if (!(pdv)) {
> + printk(KERN_ERR "Unable to locate struct pscsi_dev_virt"
> + " parameter\n");
> + return NULL;
> + }
> + /*
> + * 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) {
> + printk(KERN_ERR "pSCSI: Unable to locate struct"
> + " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
> + return NULL;
> + }
> + /*
> + * 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)) {
> + printk(KERN_ERR "pSCSI: udev_path attribute has not"
> + " been set before ENABLE=1\n");
> + return NULL;
> + }
> + /*
> + * 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))) {
> + printk(KERN_ERR "pSCSI: Unable to set hba_mode"
> + " with active devices\n");
> + spin_unlock(&hba->device_lock);
> + return NULL;
> + }
> + spin_unlock(&hba->device_lock);
> +
> + if (pscsi_pmode_enable_hba(hba, 1) != 1)
> + return NULL;
> +
> + legacy_mode_enable = 1;
> + hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
> + sh = phv->phv_lld_host;
> + } else {
> + sh = pscsi_get_sh(pdv->pdv_host_id);
> + if (!(sh)) {
> + printk(KERN_ERR "pSCSI: Unable to locate"
> + " pdv_host_id: %d\n", pdv->pdv_host_id);
> + return NULL;
> + }
> + }
> + } else {
> + if (phv->phv_mode == PHV_VIRUTAL_HOST_ID) {
> + printk(KERN_ERR "pSCSI: PHV_VIRUTAL_HOST_ID set while"
> + " struct Scsi_Host exists\n");
> + return NULL;
> + }
> + }
> +
> + 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 NULL;
> + }
> + return dev;
> + }
> + spin_unlock_irq(sh->host_lock);
> +
> + printk(KERN_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 NULL;
> +}
> +
> +/* pscsi_activate_device(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static int pscsi_activate_device(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *) pdv->pdv_se_hba->hba_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> + struct Scsi_Host *sh = sd->host;
> +
> + printk(KERN_INFO "CORE_PSCSI[%d] - Activating Device with TCQ: %d at"
> + " SCSI Location (Host/Channel/Target/LUN) %d/%d/%d/%d\n",
> + phv->phv_host_id, sd->queue_depth, sh->host_no, sd->channel,
> + sd->id, sd->lun);
> +
> + return 0;
> +}
> +
> +/* pscsi_deactivate_device(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static void pscsi_deactivate_device(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *) pdv->pdv_se_hba->hba_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> + struct Scsi_Host *sh = sd->host;
> +
> + printk(KERN_INFO "CORE_PSCSI[%d] - Deactivating Device with TCQ: %d at"
> + " SCSI Location (Host/Channel/Target/LUN) %d/%d/%d/%d\n",
> + phv->phv_host_id, sd->queue_depth, sh->host_no, sd->channel,
> + sd->id, sd->lun);
> +}
> +
> +/* pscsi_free_device(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static void pscsi_free_device(void *p)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) p;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *) pdv->pdv_se_hba->hba_ptr;
> + struct scsi_device *sd = (struct scsi_device *) 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) {
> + close_bdev_exclusive(pdv->pdv_bd,
> + FMODE_WRITE|FMODE_READ);
> + 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);
> +}
> +
> +/* pscsi_transport_complete():
> + *
> + *
> + */
> +static int pscsi_transport_complete(struct se_task *task)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) task->se_dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> + int result;
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> + 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_CMD(task)->se_deve)
> + goto after_mode_sense;
> +
> + if (TASK_CMD(task)->se_deve->lun_flags &
> + TRANSPORT_LUNFLAGS_READ_ONLY) {
> + unsigned char *buf = (unsigned char *)
> + T_TASK(task->task_se_cmd)->t_task_buf;
> +
> + if (cdb[0] == MODE_SENSE_10) {
> + if (!(buf[3] & 0x80))
> + buf[3] |= 0x80;
> + } else {
> + if (!(buf[2] & 0x80))
> + buf[2] |= 0x80;
> + }
> + }
> + }
> +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)) {
> + printk(KERN_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;
> +}
> +
> +/* pscsi_allocate_request(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static void *pscsi_allocate_request(
> + struct se_task *task,
> + struct se_device *dev)
> +{
> + struct pscsi_plugin_task *pt;
> +
> + pt = kzalloc(sizeof(struct pscsi_plugin_task), GFP_KERNEL);
> + if (!(pt)) {
> + printk(KERN_ERR "Unable to allocate struct pscsi_plugin_task\n");
> + return NULL;
> + }
> +
> + return pt;
> +}
> +
> +static inline void pscsi_blk_init_request(
> + struct se_task *task,
> + struct pscsi_plugin_task *pt,
> + struct request *req,
> + int bidi_read)
> +{
> + /*
> + * Defined as "scsi command" in include/linux/blkdev.h.
> + */
> + req->cmd_type = REQ_TYPE_BLOCK_PC;
> + /*
> + * For the extra BIDI-COMMAND READ struct request we do not
> + * need to setup the remaining structure members
> + */
> + if (bidi_read)
> + return;
> + /*
> + * Setup the done function pointer for struct request,
> + * also set the end_io_data pointer.to struct se_task.
> + */
> + req->end_io = pscsi_req_done;
> + req->end_io_data = (void *)task;
> + /*
> + * Load the referenced struct se_task's SCSI CDB into
> + * include/linux/blkdev.h:struct request->cmd
> + */
> + req->cmd_len = scsi_command_size(pt->pscsi_cdb);
> + req->cmd = &pt->pscsi_cdb[0];
Here! req->cmd = TASK_CMD(task)->t_task_cdb;
I don't see in this patch the actual memcpy of TASK_CMD(task)->t_task_cdb into
pt->pscsi_cdb, which I suspect is done in Generic code through the use of
->get_cdb(struct se_task *);?
If so then it means all the plugins have their own copy of the CDB? Now I finally
understand the get_max_cdb_len().
All that could be totally clean. All plugins use the TASK_CMD(task)->t_task_cdb
directly. Then get_max_cdb_len(), get_cdb(), the memcpy() and all these extra buffers
just magically go away.
> + /*
> + * Setup pointer for outgoing sense data.
> + */
> + req->sense = (void *)&pt->pscsi_sense[0];
What about sense Surly that is generic just as cdb is. Could you use the
task's sense?
> + req->sense_len = 0;
> +}
> +
> +/*
> + * Used for pSCSI data payloads for all *NON* SCF_SCSI_DATA_SG_IO_CDB
> +*/
> +static int pscsi_blk_get_request(struct se_task *task)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) task->se_dev->dev_ptr;
> +
> + pt->pscsi_req = blk_get_request(pdv->pdv_sd->request_queue,
> + (pt->pscsi_direction == DMA_TO_DEVICE), GFP_KERNEL);
> + if (!(pt->pscsi_req) || IS_ERR(pt->pscsi_req)) {
> + printk(KERN_ERR "PSCSI: blk_get_request() failed: %ld\n",
> + IS_ERR(pt->pscsi_req));
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> + }
> + /*
> + * Setup the newly allocated struct request for REQ_TYPE_BLOCK_PC,
> + * and setup rq callback, CDB and sense.
> + */
> + pscsi_blk_init_request(task, pt, pt->pscsi_req, 0);
> + return 0;
> +}
> +
> +/* pscsi_do_task(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static int pscsi_do_task(struct se_task *task)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) task->se_dev->dev_ptr;
> + /*
> + * Set the struct request->timeout value based on peripheral
> + * device type from SCSI.
> + */
> + if (pdv->pdv_sd->type == TYPE_DISK)
> + pt->pscsi_req->timeout = PS_TIMEOUT_DISK;
> + else
> + pt->pscsi_req->timeout = PS_TIMEOUT_OTHER;
> +
> + pt->pscsi_req->retries = PS_RETRY;
> + /*
> + * Queue the struct request into the struct scsi_device->request_queue.
> + */
> + blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL,
> + pt->pscsi_req, 1, pscsi_req_done);
> +
/**
* blk_execute_rq_nowait - insert a request into queue for execution
* @q: queue to insert the request in
* @bd_disk: matching gendisk
* @rq: request to insert
* @at_head: insert request at head or tail of queue
* @done: I/O completion handler
*
Surly you did not mean to use at_head==1? That is a very bad BUG. I bet
this plugin was never heavily used.
> + return PYX_TRANSPORT_SENT_TO_TRANSPORT;
> +}
> +
> +/* pscsi_free_task(): (Part of se_subsystem_api_t template)
> + *
> + *
> + */
> +static void pscsi_free_task(struct se_task *task)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *)task->transport_req;
> + /*
> + * 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);
> +}
> +
> +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 = (struct pscsi_dev_virt *) se_dev->se_dev_su_ptr;
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
> + char *buf, *cur, *ptr, *ptr2;
> + unsigned long scsi_host_id, scsi_channel_id;
> + unsigned long scsi_target_id, scsi_lun_id;
> + int params = 0, ret;
> +
> + buf = kzalloc(count, GFP_KERNEL);
> + if (!(buf)) {
> + printk(KERN_ERR "Unable to allocate memory for temporary"
> + " buffer\n");
> + return -ENOMEM;
> + }
> + memcpy(buf, page, count);
> + cur = buf;
> +
> + while (cur) {
> + ptr = strstr(cur, "=");
> + if (!(ptr))
> + goto out;
> +
> + *ptr = '\0';
> + ptr++;
> +
> + ptr2 = strstr(cur, "scsi_host_id");
> + if ((ptr2)) {
> + transport_check_dev_params_delim(ptr, &cur);
> + if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
> + printk(KERN_ERR "PSCSI[%d]: Unable to accept"
> + " scsi_host_id while phv_mode =="
> + " PHV_LLD_SCSI_HOST_NO\n",
> + phv->phv_host_id);
> + break;
> + }
> + ret = strict_strtoul(ptr, 0, &scsi_host_id);
> + if (ret < 0) {
> + printk(KERN_ERR "strict_strtoul() failed for"
> + " scsi_hostl_id=\n");
> + break;
> + }
> + pdv->pdv_host_id = (int)scsi_host_id;
> + printk(KERN_INFO "PSCSI[%d]: Referencing SCSI Host ID:"
> + " %d\n", phv->phv_host_id, pdv->pdv_host_id);
> + pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
> + params++;
> + continue;
> + }
> + ptr2 = strstr(cur, "scsi_channel_id");
> + if ((ptr2)) {
> + transport_check_dev_params_delim(ptr, &cur);
> + ret = strict_strtoul(ptr, 0, &scsi_channel_id);
> + if (ret < 0) {
> + printk(KERN_ERR "strict_strtoul() failed for"
> + " scsi_channel_id=\n");
> + break;
> + }
> + pdv->pdv_channel_id = (int)scsi_channel_id;
> + printk(KERN_INFO "PSCSI[%d]: Referencing SCSI Channel"
> + " ID: %d\n", phv->phv_host_id,
> + pdv->pdv_channel_id);
> + pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
> + params++;
> + continue;
> + }
> + ptr2 = strstr(cur, "scsi_target_id");
> + if ((ptr2)) {
> + transport_check_dev_params_delim(ptr, &cur);
> + ret = strict_strtoul(ptr, 0, &scsi_target_id);
> + if (ret < 0) {
> + printk("strict_strtoul() failed for"
> + " strict_strtoul()\n");
> + break;
> + }
> + pdv->pdv_target_id = (int)scsi_target_id;
> + printk(KERN_INFO "PSCSI[%d]: Referencing SCSI Target"
> + " ID: %d\n", phv->phv_host_id,
> + pdv->pdv_target_id);
> + pdv->pdv_flags |= PDF_HAS_TARGET_ID;
> + params++;
> + continue;
> + }
> + ptr2 = strstr(cur, "scsi_lun_id");
> + if ((ptr2)) {
> + transport_check_dev_params_delim(ptr, &cur);
> + ret = strict_strtoul(ptr, 0, &scsi_lun_id);
> + if (ret < 0) {
> + printk("strict_strtoul() failed for"
> + " scsi_lun_id=\n");
> + break;
> + }
> + pdv->pdv_lun_id = (int)scsi_lun_id;
> + printk(KERN_INFO "PSCSI[%d]: Referencing SCSI LUN ID:"
> + " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
> + pdv->pdv_flags |= PDF_HAS_LUN_ID;
> + params++;
> + } else
> + cur = NULL;
> + }
> +
> +out:
> + kfree(buf);
> + return (params) ? count : -EINVAL;
> +}
> +
> +static ssize_t pscsi_check_configfs_dev_params(
> + struct se_hba *hba,
> + struct se_subsystem_dev *se_dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) 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)) {
> + printk(KERN_ERR "Missing scsi_channel_id=, scsi_target_id= and"
> + " scsi_lun_id= parameters\n");
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +static ssize_t pscsi_show_configfs_dev_params(
> + struct se_hba *hba,
> + struct se_subsystem_dev *se_dev,
> + char *page)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) se_dev->se_dev_su_ptr;
> + int bl = 0;
> +
> + __pscsi_get_dev_info(pdv, page, &bl);
> + return (ssize_t)bl;
> +}
> +
> +static void pscsi_get_plugin_info(void *p, char *b, int *bl)
> +{
> + *bl += sprintf(b + *bl, "TCM SCSI Plugin %s\n", PSCSI_VERSION);
> +}
> +
> +static void pscsi_get_hba_info(struct se_hba *hba, char *b, int *bl)
> +{
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
> + struct Scsi_Host *sh = phv->phv_lld_host;
> +
> + *bl += sprintf(b + *bl, "Core Host ID: %u PHV Host ID: %u\n",
> + hba->hba_id, phv->phv_host_id);
> + if (sh)
> + *bl += sprintf(b + *bl, " SCSI HBA ID %u: %s <local>\n",
> + sh->host_no, (sh->hostt->name) ?
> + (sh->hostt->name) : "Unknown");
> +}
> +
> +static void pscsi_get_dev_info(struct se_device *dev, char *b, int *bl)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> +
> + __pscsi_get_dev_info(pdv, b, bl);
> +}
> +
> +static void __pscsi_get_dev_info(struct pscsi_dev_virt *pdv, char *b, int *bl)
> +{
> + struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *) pdv->pdv_se_hba->hba_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> + unsigned char host_id[16];
> + 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 + *bl, "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");
> + }
> +}
> +
> +static void pscsi_bi_endio(struct bio *bio, int error)
> +{
> + bio_put(bio);
> +}
> +
> +static inline struct bio *pscsi_get_bio(struct pscsi_dev_virt *pdv, 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)) {
> + printk(KERN_ERR "PSCSI: bio_kmalloc() failed\n");
> + return NULL;
> + }
> + bio->bi_end_io = pscsi_bi_endio;
> +
> + return bio;
> +}
> +
> +#if 0
> +#define DEBUG_PSCSI(x...) printk(x)
> +#else
> +#define DEBUG_PSCSI(x...)
> +#endif
> +
> +static int __pscsi_map_task_SG(
> + struct se_task *task,
> + struct scatterlist *task_sg,
> + u32 task_sg_num,
> + int bidi_read)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) task->se_dev->dev_ptr;
> + struct bio *bio = NULL, *hbio = 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 +
Please forgive me I must be looking at an old patch but this is what I could find
in my mail box.
task->task_size? there must be two of them one for write/uni one for bidi_read
> + PAGE_SIZE - 1) >> PAGE_SHIFT;
> + int nr_vecs = 0, ret = 0;
> + int rw = (TASK_CMD(task)->data_direction == DMA_TO_DEVICE);
> +
> + if (!task->task_size)
dito
> + return 0;
> + /*
> + * For SCF_SCSI_DATA_SG_IO_CDB, Use fs/bio.c:bio_add_page() to setup
> + * the bio_vec maplist from TC< struct se_mem -> task->task_sg ->
> + * struct scatterlist memory. The struct se_task->task_sg[] currently needs
> + * to be attached to struct bios for submission to Linux/SCSI using
> + * struct request to struct scsi_device->request_queue.
> + *
> + * Note that this will be changing post v2.6.28 as Target_Core_Mod/pSCSI
> + * is ported to upstream SCSI passthrough functionality that accepts
> + * struct scatterlist->page_link or struct page as a paraemeter.
> + */
> + DEBUG_PSCSI("PSCSI: nr_pages: %d\n", nr_pages);
> +
> + for_each_sg(task_sg, sg, task_sg_num, i) {
Good received from caller
> + page = sg_page(sg);
> + off = sg->offset;
> + len = sg->length;
> +
> + DEBUG_PSCSI("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(pdv, nr_vecs);
> + if (!(bio))
> + goto fail;
> +
> + if (rw)
> + bio->bi_rw |= REQ_WRITE;
> +
> + DEBUG_PSCSI("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;
> + }
> +
> + DEBUG_PSCSI("PSCSI: Calling bio_add_pc_page() i: %d"
> + " bio: %p page: %p len: %d off: %d\n", i, bio,
> + page, len, off);
> +
> + ret = bio_add_pc_page(pdv->pdv_sd->request_queue,
> + bio, page, bytes, off);
> + if (ret != bytes)
> + goto fail;
> +
> + DEBUG_PSCSI("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
> + bio->bi_vcnt, nr_vecs);
> +
> + if (bio->bi_vcnt > nr_vecs) {
> + DEBUG_PSCSI("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;
> + }
> + }
> + /*
> + * Setup the primary pt->pscsi_req used for non BIDI and BIDI-COMMAND
> + * primary SCSI WRITE poayload mapped for struct se_task->task_sg[]
> + */
> + if (!(bidi_read)) {
> + /*
> + * Starting with v2.6.31, call blk_make_request() passing in *hbio to
> + * allocate the pSCSI task a struct request.
> + */
> + pt->pscsi_req = blk_make_request(pdv->pdv_sd->request_queue,
> + hbio, GFP_KERNEL);
> + if (!(pt->pscsi_req)) {
> + printk(KERN_ERR "pSCSI: blk_make_request() failed\n");
> + goto fail;
> + }
> + /*
> + * Setup the newly allocated struct request for REQ_TYPE_BLOCK_PC,
> + * and setup rq callback, CDB and sense.
> + */
> + pscsi_blk_init_request(task, pt, pt->pscsi_req, 0);
> +
> + return task->task_sg_num;
return task_sg_num ??
> + }
> + /*
> + * Setup the secondary pt->pscsi_req_bidi used for the extra BIDI-COMMAND
> + * SCSI READ paylaod mapped for struct se_task->task_sg_bidi[]
> + */
> + pt->pscsi_req_bidi = blk_make_request(pdv->pdv_sd->request_queue,
> + hbio, GFP_KERNEL);
> + if (!(pt->pscsi_req_bidi)) {
> + printk(KERN_ERR "pSCSI: blk_make_request() failed for BIDI\n");
> + goto fail;
> + }
> + pscsi_blk_init_request(task, pt, pt->pscsi_req_bidi, 1);
> + /*
> + * Setup the magic BIDI-COMMAND ->next_req pointer to the original
> + * pt->pscsi_req.
> + */
> + pt->pscsi_req->next_rq = pt->pscsi_req_bidi;
> +
> + return task->task_sg_num;
return task_sg_num ??
> +fail:
> + while (hbio) {
> + bio = hbio;
> + hbio = hbio->bi_next;
> + bio->bi_next = NULL;
> + bio_endio(bio, 0);
> + }
> + return ret;
> +}
> +
> +static int pscsi_map_task_SG(struct se_task *task)
> +{
> + int ret;
> + /*
> + * Setup the main struct request for the task->task_sg[] payload
> + */
> +
> + ret = __pscsi_map_task_SG(task, task->task_sg, task->task_sg_num, 0);
> + if (ret < 0)
> + return ret;
> +
> + if (!(task->task_sg_bidi))
> + return ret;
> + /*
> + * If present, set up the extra BIDI-COMMAND SCSI READ
> + * struct request and payload.
> + */
> + return __pscsi_map_task_SG(task, task->task_sg_bidi,
> + task->task_sg_num, 1);
The second __pscsi_map_task_SG can fail. Do you make sure to free
the successful first __pscsi_map_task_SG?
> +}
> +
> +/* pscsi_map_task_non_SG():
> + *
> + *
> + */
> +static int pscsi_map_task_non_SG(struct se_task *task)
> +{
> + struct se_cmd *cmd = TASK_CMD(task);
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) task->se_dev->dev_ptr;
> + int ret = 0;
> +
> + if (!task->task_size)
> + return 0;
> +
> + ret = blk_rq_map_kern(pdv->pdv_sd->request_queue,
> + pt->pscsi_req, T_TASK(cmd)->t_task_buf,
> + task->task_size, GFP_KERNEL);
> + if (ret < 0) {
> + printk(KERN_ERR "PSCSI: blk_rq_map_kern() failed: %d\n", ret);
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> + }
> + return 0;
> +}
> +
> +static int pscsi_CDB_none(struct se_task *task, u32 size)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + pt->pscsi_direction = DMA_NONE;
> +
> + return pscsi_blk_get_request(task);
> +}
> +
> +/* pscsi_CDB_read_non_SG():
> + *
> + *
> + */
> +static int pscsi_CDB_read_non_SG(struct se_task *task, u32 size)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + pt->pscsi_direction = DMA_FROM_DEVICE;
> +
> + if (pscsi_blk_get_request(task) < 0)
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> +
> + return pscsi_map_task_non_SG(task);
> +}
> +
> +/* pscsi_CDB_read_SG():
> + *
> + *
> + */
> +static int pscsi_CDB_read_SG(struct se_task *task, u32 size)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + pt->pscsi_direction = DMA_FROM_DEVICE;
> + /*
> + * pscsi_map_task_SG() calls block/blk-core.c:blk_make_request()
> + * for >= v2.6.31 pSCSI
> + */
> + if (pscsi_map_task_SG(task) < 0)
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> +
> + return task->task_sg_num;
> +}
> +
> +/* pscsi_CDB_write_non_SG():
> + *
> + *
> + */
> +static int pscsi_CDB_write_non_SG(struct se_task *task, u32 size)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + pt->pscsi_direction = DMA_TO_DEVICE;
> +
> + if (pscsi_blk_get_request(task) < 0)
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> +
> + return pscsi_map_task_non_SG(task);
> +}
> +
> +/* pscsi_CDB_write_SG():
> + *
> + *
> + */
> +static int pscsi_CDB_write_SG(struct se_task *task, u32 size)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + pt->pscsi_direction = DMA_TO_DEVICE;
> + /*
> + * pscsi_map_task_SG() calls block/blk-core.c:blk_make_request()
> + * for >= v2.6.31 pSCSI
> + */
> + if (pscsi_map_task_SG(task) < 0)
> + return PYX_TRANSPORT_LU_COMM_FAILURE;
> +
> + return task->task_sg_num;
> +}
> +
> +/* pscsi_check_lba():
> + *
> + *
> + */
> +static int pscsi_check_lba(unsigned long long lba, struct se_device *dev)
> +{
> + return 0;
> +}
> +
> +/* pscsi_check_for_SG():
> + *
> + *
> + */
> +static int pscsi_check_for_SG(struct se_task *task)
> +{
> + return task->task_sg_num;
> +}
> +
> +/* pscsi_get_cdb():
> + *
> + *
> + */
> +static unsigned char *pscsi_get_cdb(struct se_task *task)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
> +
> + return pt->pscsi_cdb;
> +}
> +
> +/* pscsi_get_sense_buffer():
> + *
> + *
> + */
> +static unsigned char *pscsi_get_sense_buffer(struct se_task *task)
> +{
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
All over these. Don't cast a void pointer.
> +
> + return (unsigned char *)&pt->pscsi_sense[0];
> +}
> +
> +/* pscsi_get_blocksize():
> + *
> + *
> + */
> +static u32 pscsi_get_blocksize(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> +
> + return sd->sector_size;
> +}
> +
> +/* pscsi_get_device_rev():
> + *
> + *
> + */
> +static u32 pscsi_get_device_rev(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) 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 = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> +
> + return sd->type;
> +}
> +
> +/* pscsi_get_dma_length():
> + *
> + *
> + */
> +static u32 pscsi_get_dma_length(u32 task_size, struct se_device *dev)
> +{
> + return PAGE_SIZE;
??
> +}
> +
> +/* pscsi_get_max_sectors():
> + *
> + *
> + */
> +static u32 pscsi_get_max_sectors(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> +
> + return (sd->host->max_sectors > sd->request_queue->limits.max_sectors) ?
> + sd->request_queue->limits.max_sectors : sd->host->max_sectors;
> +}
> +
> +/* pscsi_get_queue_depth():
> + *
> + *
> + */
> +static u32 pscsi_get_queue_depth(struct se_device *dev)
> +{
> + struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *) dev->dev_ptr;
> + struct scsi_device *sd = (struct scsi_device *) pdv->pdv_sd;
> +
> + return sd->queue_depth;
> +}
> +
> +/* 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;
> + printk(KERN_INFO "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:
> + printk(KERN_INFO "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_error_status = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
> + TASK_CMD(task)->transport_error_status =
> + PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
> + transport_complete_task(task, 0);
> + break;
> + }
> +
> + return;
> +}
> +
> +static void pscsi_req_done(struct request *req, int uptodate)
> +{
> + struct se_task *task = (struct se_task *)req->end_io_data;
> + struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *)task->transport_req;
> +
> + pt->pscsi_result = req->errors;
> + pt->pscsi_resid = req->resid_len;
> +
> + pscsi_process_SAM_status(task, pt);
> +
> + if (req->next_rq != NULL) {
> + __blk_put_request(req->q, req->next_rq);
> + pt->pscsi_req_bidi = NULL;
req->next_rq = NULL
Actually pt->pscsi_req_bidi is never used, it's set and reset
only req->next_rq is used. You are fine without it. You have
pt->pscsi_req and pt->pscsi_req->next_rq;
> + }
> +
> + __blk_put_request(req->q, req);
> + pt->pscsi_req = NULL;
> +}
> +
> +static struct se_subsystem_api pscsi_template = {
> + .name = "pscsi",
> + .type = PSCSI,
> + .transport_type = TRANSPORT_PLUGIN_PHBA_PDEV,
> + .external_submod = 1,
> + .cdb_none = pscsi_CDB_none,
> + .cdb_read_non_SG = pscsi_CDB_read_non_SG,
> + .cdb_read_SG = pscsi_CDB_read_SG,
> + .cdb_write_non_SG = pscsi_CDB_write_non_SG,
> + .cdb_write_SG = pscsi_CDB_write_SG,
> + .attach_hba = pscsi_attach_hba,
> + .detach_hba = pscsi_detach_hba,
> + .pmode_enable_hba = pscsi_pmode_enable_hba,
> + .activate_device = pscsi_activate_device,
> + .deactivate_device = pscsi_deactivate_device,
> + .allocate_virtdevice = pscsi_allocate_virtdevice,
> + .create_virtdevice = pscsi_create_virtdevice,
> + .free_device = pscsi_free_device,
> + .transport_complete = pscsi_transport_complete,
> + .allocate_request = pscsi_allocate_request,
> + .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,
> + .create_virtdevice_from_fd = NULL,
> + .get_plugin_info = pscsi_get_plugin_info,
> + .get_hba_info = pscsi_get_hba_info,
> + .get_dev_info = pscsi_get_dev_info,
> + .check_lba = pscsi_check_lba,
> + .check_for_SG = pscsi_check_for_SG,
> + .get_cdb = pscsi_get_cdb,
> + .get_sense_buffer = pscsi_get_sense_buffer,
> + .get_blocksize = pscsi_get_blocksize,
> + .get_device_rev = pscsi_get_device_rev,
> + .get_device_type = pscsi_get_device_type,
> + .get_dma_length = pscsi_get_dma_length,
> + .get_max_sectors = pscsi_get_max_sectors,
> + .get_queue_depth = pscsi_get_queue_depth,
> + .write_pending = NULL,
> +};
> +
> +int __init pscsi_module_init(void)
> +{
> + int ret;
> +
> + INIT_LIST_HEAD(&pscsi_template.sub_api_list);
> +
> + ret = transport_subsystem_register(&pscsi_template, THIS_MODULE);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +void pscsi_module_exit(void)
> +{
> + transport_subsystem_release(&pscsi_template);
> +}
> +
> +MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
> +MODULE_AUTHOR("nab@xxxxxxxxxxxxxxx");
> +MODULE_LICENSE("GPL");
> +
> +module_init(pscsi_module_init);
> +module_exit(pscsi_module_exit);
> diff --git a/drivers/target/target_core_pscsi.h b/drivers/target/target_core_pscsi.h
> new file mode 100644
> index 0000000..d3c8972
> --- /dev/null
> +++ b/drivers/target/target_core_pscsi.h
> @@ -0,0 +1,69 @@
> +#ifndef TARGET_CORE_PSCSI_H
> +#define TARGET_CORE_PSCSI_H
> +
> +#define PSCSI_VERSION "v4.0"
> +#define PSCSI_VIRTUAL_HBA_DEPTH 2048
> +
> +/* used in pscsi_find_alloc_len() */
> +#ifndef INQUIRY_DATA_SIZE
> +#define INQUIRY_DATA_SIZE 0x24
> +#endif
> +
> +/* used in pscsi_add_device_to_list() */
> +#define PSCSI_DEFAULT_QUEUEDEPTH 1
> +
> +#define PS_RETRY 5
> +#define PS_TIMEOUT_DISK (15*HZ)
> +#define PS_TIMEOUT_OTHER (500*HZ)
> +
> +extern struct se_global *se_global;
> +extern struct block_device *linux_blockdevice_claim(int, int, void *);
> +extern int linux_blockdevice_release(int, int, struct block_device *);
> +extern int linux_blockdevice_check(int, int);
> +
> +#include <linux/device.h>
> +#include <scsi/scsi_driver.h>
> +#include <scsi/scsi_device.h>
> +#include <linux/kref.h>
> +#include <linux/kobject.h>
> +
> +struct pscsi_plugin_task {
> + unsigned char pscsi_cdb[TCM_MAX_COMMAND_SIZE];
> + unsigned char pscsi_sense[SCSI_SENSE_BUFFERSIZE];
> + int pscsi_direction;
> + int pscsi_result;
> + u32 pscsi_resid;
Scsi has two residual results. One inside each request.
> + struct request *pscsi_req;
> + struct request *pscsi_req_bidi;
> +} ____cacheline_aligned;
> +
> +#define PDF_HAS_CHANNEL_ID 0x01
> +#define PDF_HAS_TARGET_ID 0x02
> +#define PDF_HAS_LUN_ID 0x04
> +#define PDF_HAS_VPD_UNIT_SERIAL 0x08
> +#define PDF_HAS_VPD_DEV_IDENT 0x10
> +#define PDF_HAS_VIRT_HOST_ID 0x20
> +
> +struct pscsi_dev_virt {
> + int pdv_flags;
> + int pdv_host_id;
> + int pdv_channel_id;
> + int pdv_target_id;
> + int pdv_lun_id;
> + struct block_device *pdv_bd;
> + struct scsi_device *pdv_sd;
> + struct se_hba *pdv_se_hba;
> +} ____cacheline_aligned;
> +
> +typedef enum phv_modes {
> + PHV_VIRUTAL_HOST_ID,
> + PHV_LLD_SCSI_HOST_NO
> +} phv_modes_t;
> +
> +struct pscsi_hba_virt {
> + int phv_host_id;
> + phv_modes_t phv_mode;
> + struct Scsi_Host *phv_lld_host;
> +} ____cacheline_aligned;
> +
> +#endif /*** TARGET_CORE_PSCSI_H ***/
Nic all over these patches you have
+ struct pscsi_plugin_task *pt = (struct pscsi_plugin_task *) task->transport_req;
Don't cast void pointers, please. That would be a big fat change just search for transport_req.
OK So I'm stopping to review from email and will next go to the gitweb URL you sent me. Because
in all my mailbox patches I cannot find where the task->transport_req is set, which means I'm
missing some of them. The thing I wanted to know is if there is a 1-to-1 lifetime association
between a plugin task like pscsi_plugin_task and the task-> which holds it. (On ->transport_req)
If yes, you might consider an embedded se_task in each plugin_task and the use of container_of.
Faster, more robust and cleans code considerably.
But I'll have a look at the latest code later.
Thanks
Boaz
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