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linux/drivers/scsi/libsas/sas_scsi_host.c
Darrick J. Wong 6d4dcd4dae [SCSI] libsas: Reset timer on taskless scsi_cmnds in sas_scsi_timed_out
Every so often, a scsi_cmnd will time out, and the libsas timeout handler
will discover that the scsi_cmnd does not have a sas_task attached to it.
This can happen in two cases: (1) the scsi_cmnd actually made it through
libsas to the HBA and is now going through scsi_done, or (2) the
scsi_cmnd has been held up (host lock, slab alloc, etc) and libsas has
not yet attached a sas_task.  In both cases, it is safe to ask SCSI for
more time to process the command via EH_RESET_TIMER; we cannot blindly
return EH_HANDLED because if (2) happens, we could end up calling
scsi_done while another CPU is heading towards sas_queuecommand, which
causes slab corruption when sas_task_done updates the freed scsi_cmnd.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-01-13 16:13:38 -06:00

883 lines
23 KiB
C

/*
* Serial Attached SCSI (SAS) class SCSI Host glue.
*
* Copyright (C) 2005 Adaptec, Inc. All rights reserved.
* Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
*
* This file is licensed under GPLv2.
*
* 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 "sas_internal.h"
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "../scsi_sas_internal.h"
#include "../scsi_transport_api.h"
#include <linux/err.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>
/* ---------- SCSI Host glue ---------- */
#define TO_SAS_TASK(_scsi_cmd) ((void *)(_scsi_cmd)->host_scribble)
#define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
static void sas_scsi_task_done(struct sas_task *task)
{
struct task_status_struct *ts = &task->task_status;
struct scsi_cmnd *sc = task->uldd_task;
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(sc->device->host);
unsigned ts_flags = task->task_state_flags;
int hs = 0, stat = 0;
if (unlikely(!sc)) {
SAS_DPRINTK("task_done called with non existing SCSI cmnd!\n");
list_del_init(&task->list);
sas_free_task(task);
return;
}
if (ts->resp == SAS_TASK_UNDELIVERED) {
/* transport error */
hs = DID_NO_CONNECT;
} else { /* ts->resp == SAS_TASK_COMPLETE */
/* task delivered, what happened afterwards? */
switch (ts->stat) {
case SAS_DEV_NO_RESPONSE:
case SAS_INTERRUPTED:
case SAS_PHY_DOWN:
case SAS_NAK_R_ERR:
case SAS_OPEN_TO:
hs = DID_NO_CONNECT;
break;
case SAS_DATA_UNDERRUN:
sc->resid = ts->residual;
if (sc->request_bufflen - sc->resid < sc->underflow)
hs = DID_ERROR;
break;
case SAS_DATA_OVERRUN:
hs = DID_ERROR;
break;
case SAS_QUEUE_FULL:
hs = DID_SOFT_ERROR; /* retry */
break;
case SAS_DEVICE_UNKNOWN:
hs = DID_BAD_TARGET;
break;
case SAS_SG_ERR:
hs = DID_PARITY;
break;
case SAS_OPEN_REJECT:
if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
hs = DID_SOFT_ERROR; /* retry */
else
hs = DID_ERROR;
break;
case SAS_PROTO_RESPONSE:
SAS_DPRINTK("LLDD:%s sent SAS_PROTO_RESP for an SSP "
"task; please report this\n",
task->dev->port->ha->sas_ha_name);
break;
case SAS_ABORTED_TASK:
hs = DID_ABORT;
break;
case SAM_CHECK_COND:
memcpy(sc->sense_buffer, ts->buf,
max(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
stat = SAM_CHECK_COND;
break;
default:
stat = ts->stat;
break;
}
}
ASSIGN_SAS_TASK(sc, NULL);
sc->result = (hs << 16) | stat;
list_del_init(&task->list);
sas_free_task(task);
/* This is very ugly but this is how SCSI Core works. */
if (ts_flags & SAS_TASK_STATE_ABORTED)
scsi_eh_finish_cmd(sc, &sas_ha->eh_done_q);
else
sc->scsi_done(sc);
}
static enum task_attribute sas_scsi_get_task_attr(struct scsi_cmnd *cmd)
{
enum task_attribute ta = TASK_ATTR_SIMPLE;
if (cmd->request && blk_rq_tagged(cmd->request)) {
if (cmd->device->ordered_tags &&
(cmd->request->cmd_flags & REQ_HARDBARRIER))
ta = TASK_ATTR_HOQ;
}
return ta;
}
static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
struct domain_device *dev,
gfp_t gfp_flags)
{
struct sas_task *task = sas_alloc_task(gfp_flags);
struct scsi_lun lun;
if (!task)
return NULL;
*(u32 *)cmd->sense_buffer = 0;
task->uldd_task = cmd;
ASSIGN_SAS_TASK(cmd, task);
task->dev = dev;
task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
task->ssp_task.retry_count = 1;
int_to_scsilun(cmd->device->lun, &lun);
memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
task->ssp_task.task_attr = sas_scsi_get_task_attr(cmd);
memcpy(task->ssp_task.cdb, cmd->cmnd, 16);
task->scatter = cmd->request_buffer;
task->num_scatter = cmd->use_sg;
task->total_xfer_len = cmd->request_bufflen;
task->data_dir = cmd->sc_data_direction;
task->task_done = sas_scsi_task_done;
return task;
}
static int sas_queue_up(struct sas_task *task)
{
struct sas_ha_struct *sas_ha = task->dev->port->ha;
struct scsi_core *core = &sas_ha->core;
unsigned long flags;
LIST_HEAD(list);
spin_lock_irqsave(&core->task_queue_lock, flags);
if (sas_ha->lldd_queue_size < core->task_queue_size + 1) {
spin_unlock_irqrestore(&core->task_queue_lock, flags);
return -SAS_QUEUE_FULL;
}
list_add_tail(&task->list, &core->task_queue);
core->task_queue_size += 1;
spin_unlock_irqrestore(&core->task_queue_lock, flags);
up(&core->queue_thread_sema);
return 0;
}
/**
* sas_queuecommand -- Enqueue a command for processing
* @parameters: See SCSI Core documentation
*
* Note: XXX: Remove the host unlock/lock pair when SCSI Core can
* call us without holding an IRQ spinlock...
*/
int sas_queuecommand(struct scsi_cmnd *cmd,
void (*scsi_done)(struct scsi_cmnd *))
{
int res = 0;
struct domain_device *dev = cmd_to_domain_dev(cmd);
struct Scsi_Host *host = cmd->device->host;
struct sas_internal *i = to_sas_internal(host->transportt);
spin_unlock_irq(host->host_lock);
{
struct sas_ha_struct *sas_ha = dev->port->ha;
struct sas_task *task;
res = -ENOMEM;
task = sas_create_task(cmd, dev, GFP_ATOMIC);
if (!task)
goto out;
cmd->scsi_done = scsi_done;
/* Queue up, Direct Mode or Task Collector Mode. */
if (sas_ha->lldd_max_execute_num < 2)
res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
else
res = sas_queue_up(task);
/* Examine */
if (res) {
SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
ASSIGN_SAS_TASK(cmd, NULL);
sas_free_task(task);
if (res == -SAS_QUEUE_FULL) {
cmd->result = DID_SOFT_ERROR << 16; /* retry */
res = 0;
scsi_done(cmd);
}
goto out;
}
}
out:
spin_lock_irq(host->host_lock);
return res;
}
static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
{
struct scsi_cmnd *cmd, *n;
list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
if (cmd == my_cmd)
list_del_init(&cmd->eh_entry);
}
}
static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
struct domain_device *dev)
{
struct scsi_cmnd *cmd, *n;
list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
struct domain_device *x = cmd_to_domain_dev(cmd);
if (x == dev)
list_del_init(&cmd->eh_entry);
}
}
static void sas_scsi_clear_queue_port(struct list_head *error_q,
struct asd_sas_port *port)
{
struct scsi_cmnd *cmd, *n;
list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
struct domain_device *dev = cmd_to_domain_dev(cmd);
struct asd_sas_port *x = dev->port;
if (x == port)
list_del_init(&cmd->eh_entry);
}
}
enum task_disposition {
TASK_IS_DONE,
TASK_IS_ABORTED,
TASK_IS_AT_LU,
TASK_IS_NOT_AT_LU,
};
static enum task_disposition sas_scsi_find_task(struct sas_task *task)
{
struct sas_ha_struct *ha = task->dev->port->ha;
unsigned long flags;
int i, res;
struct sas_internal *si =
to_sas_internal(task->dev->port->ha->core.shost->transportt);
if (ha->lldd_max_execute_num > 1) {
struct scsi_core *core = &ha->core;
struct sas_task *t, *n;
spin_lock_irqsave(&core->task_queue_lock, flags);
list_for_each_entry_safe(t, n, &core->task_queue, list) {
if (task == t) {
list_del_init(&t->list);
spin_unlock_irqrestore(&core->task_queue_lock,
flags);
SAS_DPRINTK("%s: task 0x%p aborted from "
"task_queue\n",
__FUNCTION__, task);
return TASK_IS_ABORTED;
}
}
spin_unlock_irqrestore(&core->task_queue_lock, flags);
}
spin_lock_irqsave(&task->task_state_lock, flags);
if (task->task_state_flags & SAS_TASK_INITIATOR_ABORTED) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("%s: task 0x%p already aborted\n",
__FUNCTION__, task);
return TASK_IS_ABORTED;
}
spin_unlock_irqrestore(&task->task_state_lock, flags);
for (i = 0; i < 5; i++) {
SAS_DPRINTK("%s: aborting task 0x%p\n", __FUNCTION__, task);
res = si->dft->lldd_abort_task(task);
spin_lock_irqsave(&task->task_state_lock, flags);
if (task->task_state_flags & SAS_TASK_STATE_DONE) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
task);
return TASK_IS_DONE;
}
spin_unlock_irqrestore(&task->task_state_lock, flags);
if (res == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("%s: task 0x%p is aborted\n",
__FUNCTION__, task);
return TASK_IS_ABORTED;
} else if (si->dft->lldd_query_task) {
SAS_DPRINTK("%s: querying task 0x%p\n",
__FUNCTION__, task);
res = si->dft->lldd_query_task(task);
if (res == TMF_RESP_FUNC_SUCC) {
SAS_DPRINTK("%s: task 0x%p at LU\n",
__FUNCTION__, task);
return TASK_IS_AT_LU;
} else if (res == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("%s: task 0x%p not at LU\n",
__FUNCTION__, task);
return TASK_IS_NOT_AT_LU;
}
}
}
return res;
}
static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
{
int res = TMF_RESP_FUNC_FAILED;
struct scsi_lun lun;
struct sas_internal *i =
to_sas_internal(dev->port->ha->core.shost->transportt);
int_to_scsilun(cmd->device->lun, &lun);
SAS_DPRINTK("eh: device %llx LUN %x has the task\n",
SAS_ADDR(dev->sas_addr),
cmd->device->lun);
if (i->dft->lldd_abort_task_set)
res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
if (res == TMF_RESP_FUNC_FAILED) {
if (i->dft->lldd_clear_task_set)
res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
}
if (res == TMF_RESP_FUNC_FAILED) {
if (i->dft->lldd_lu_reset)
res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
}
return res;
}
static int sas_recover_I_T(struct domain_device *dev)
{
int res = TMF_RESP_FUNC_FAILED;
struct sas_internal *i =
to_sas_internal(dev->port->ha->core.shost->transportt);
SAS_DPRINTK("I_T nexus reset for dev %016llx\n",
SAS_ADDR(dev->sas_addr));
if (i->dft->lldd_I_T_nexus_reset)
res = i->dft->lldd_I_T_nexus_reset(dev);
return res;
}
void sas_scsi_recover_host(struct Scsi_Host *shost)
{
struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
unsigned long flags;
LIST_HEAD(error_q);
struct scsi_cmnd *cmd, *n;
enum task_disposition res = TASK_IS_DONE;
int tmf_resp;
struct sas_internal *i = to_sas_internal(shost->transportt);
spin_lock_irqsave(shost->host_lock, flags);
list_splice_init(&shost->eh_cmd_q, &error_q);
spin_unlock_irqrestore(shost->host_lock, flags);
SAS_DPRINTK("Enter %s\n", __FUNCTION__);
/* All tasks on this list were marked SAS_TASK_STATE_ABORTED
* by sas_scsi_timed_out() callback.
*/
Again:
SAS_DPRINTK("going over list...\n");
list_for_each_entry_safe(cmd, n, &error_q, eh_entry) {
struct sas_task *task = TO_SAS_TASK(cmd);
list_del_init(&cmd->eh_entry);
if (!task) {
SAS_DPRINTK("%s: taskless cmd?!\n", __FUNCTION__);
continue;
}
SAS_DPRINTK("trying to find task 0x%p\n", task);
res = sas_scsi_find_task(task);
cmd->eh_eflags = 0;
switch (res) {
case TASK_IS_DONE:
SAS_DPRINTK("%s: task 0x%p is done\n", __FUNCTION__,
task);
task->task_done(task);
continue;
case TASK_IS_ABORTED:
SAS_DPRINTK("%s: task 0x%p is aborted\n",
__FUNCTION__, task);
task->task_done(task);
continue;
case TASK_IS_AT_LU:
SAS_DPRINTK("task 0x%p is at LU: lu recover\n", task);
tmf_resp = sas_recover_lu(task->dev, cmd);
if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("dev %016llx LU %x is "
"recovered\n",
SAS_ADDR(task->dev),
cmd->device->lun);
task->task_done(task);
sas_scsi_clear_queue_lu(&error_q, cmd);
goto Again;
}
/* fallthrough */
case TASK_IS_NOT_AT_LU:
SAS_DPRINTK("task 0x%p is not at LU: I_T recover\n",
task);
tmf_resp = sas_recover_I_T(task->dev);
if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("I_T %016llx recovered\n",
SAS_ADDR(task->dev->sas_addr));
task->task_done(task);
sas_scsi_clear_queue_I_T(&error_q, task->dev);
goto Again;
}
/* Hammer time :-) */
if (i->dft->lldd_clear_nexus_port) {
struct asd_sas_port *port = task->dev->port;
SAS_DPRINTK("clearing nexus for port:%d\n",
port->id);
res = i->dft->lldd_clear_nexus_port(port);
if (res == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("clear nexus port:%d "
"succeeded\n", port->id);
task->task_done(task);
sas_scsi_clear_queue_port(&error_q,
port);
goto Again;
}
}
if (i->dft->lldd_clear_nexus_ha) {
SAS_DPRINTK("clear nexus ha\n");
res = i->dft->lldd_clear_nexus_ha(ha);
if (res == TMF_RESP_FUNC_COMPLETE) {
SAS_DPRINTK("clear nexus ha "
"succeeded\n");
task->task_done(task);
goto out;
}
}
/* If we are here -- this means that no amount
* of effort could recover from errors. Quite
* possibly the HA just disappeared.
*/
SAS_DPRINTK("error from device %llx, LUN %x "
"couldn't be recovered in any way\n",
SAS_ADDR(task->dev->sas_addr),
cmd->device->lun);
task->task_done(task);
goto clear_q;
}
}
out:
scsi_eh_flush_done_q(&ha->eh_done_q);
SAS_DPRINTK("--- Exit %s\n", __FUNCTION__);
return;
clear_q:
SAS_DPRINTK("--- Exit %s -- clear_q\n", __FUNCTION__);
list_for_each_entry_safe(cmd, n, &error_q, eh_entry) {
struct sas_task *task = TO_SAS_TASK(cmd);
list_del_init(&cmd->eh_entry);
task->task_done(task);
}
}
enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
{
struct sas_task *task = TO_SAS_TASK(cmd);
unsigned long flags;
if (!task) {
cmd->timeout_per_command /= 2;
SAS_DPRINTK("command 0x%p, task 0x%p, gone: %s\n",
cmd, task, (cmd->timeout_per_command ?
"EH_RESET_TIMER" : "EH_NOT_HANDLED"));
if (!cmd->timeout_per_command)
return EH_NOT_HANDLED;
return EH_RESET_TIMER;
}
spin_lock_irqsave(&task->task_state_lock, flags);
if (task->task_state_flags & SAS_TASK_INITIATOR_ABORTED) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("command 0x%p, task 0x%p, aborted by initiator: "
"EH_NOT_HANDLED\n", cmd, task);
return EH_NOT_HANDLED;
}
if (task->task_state_flags & SAS_TASK_STATE_DONE) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
cmd, task);
return EH_HANDLED;
}
if (!(task->task_state_flags & SAS_TASK_AT_INITIATOR)) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("command 0x%p, task 0x%p, not at initiator: "
"EH_RESET_TIMER\n",
cmd, task);
return EH_RESET_TIMER;
}
task->task_state_flags |= SAS_TASK_STATE_ABORTED;
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_NOT_HANDLED\n",
cmd, task);
return EH_NOT_HANDLED;
}
struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
{
struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
struct domain_device *found_dev = NULL;
int i;
spin_lock(&ha->phy_port_lock);
for (i = 0; i < ha->num_phys; i++) {
struct asd_sas_port *port = ha->sas_port[i];
struct domain_device *dev;
spin_lock(&port->dev_list_lock);
list_for_each_entry(dev, &port->dev_list, dev_list_node) {
if (rphy == dev->rphy) {
found_dev = dev;
spin_unlock(&port->dev_list_lock);
goto found;
}
}
spin_unlock(&port->dev_list_lock);
}
found:
spin_unlock(&ha->phy_port_lock);
return found_dev;
}
static inline struct domain_device *sas_find_target(struct scsi_target *starget)
{
struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
return sas_find_dev_by_rphy(rphy);
}
int sas_target_alloc(struct scsi_target *starget)
{
struct domain_device *found_dev = sas_find_target(starget);
if (!found_dev)
return -ENODEV;
starget->hostdata = found_dev;
return 0;
}
#define SAS_DEF_QD 32
#define SAS_MAX_QD 64
int sas_slave_configure(struct scsi_device *scsi_dev)
{
struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
struct sas_ha_struct *sas_ha;
BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
sas_ha = dev->port->ha;
sas_read_port_mode_page(scsi_dev);
if (scsi_dev->tagged_supported) {
scsi_set_tag_type(scsi_dev, MSG_SIMPLE_TAG);
scsi_activate_tcq(scsi_dev, SAS_DEF_QD);
} else {
SAS_DPRINTK("device %llx, LUN %x doesn't support "
"TCQ\n", SAS_ADDR(dev->sas_addr),
scsi_dev->lun);
scsi_dev->tagged_supported = 0;
scsi_set_tag_type(scsi_dev, 0);
scsi_deactivate_tcq(scsi_dev, 1);
}
return 0;
}
void sas_slave_destroy(struct scsi_device *scsi_dev)
{
}
int sas_change_queue_depth(struct scsi_device *scsi_dev, int new_depth)
{
int res = min(new_depth, SAS_MAX_QD);
if (scsi_dev->tagged_supported)
scsi_adjust_queue_depth(scsi_dev, scsi_get_tag_type(scsi_dev),
res);
else {
struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
sas_printk("device %llx LUN %x queue depth changed to 1\n",
SAS_ADDR(dev->sas_addr),
scsi_dev->lun);
scsi_adjust_queue_depth(scsi_dev, 0, 1);
res = 1;
}
return res;
}
int sas_change_queue_type(struct scsi_device *scsi_dev, int qt)
{
if (!scsi_dev->tagged_supported)
return 0;
scsi_deactivate_tcq(scsi_dev, 1);
scsi_set_tag_type(scsi_dev, qt);
scsi_activate_tcq(scsi_dev, scsi_dev->queue_depth);
return qt;
}
int sas_bios_param(struct scsi_device *scsi_dev,
struct block_device *bdev,
sector_t capacity, int *hsc)
{
hsc[0] = 255;
hsc[1] = 63;
sector_div(capacity, 255*63);
hsc[2] = capacity;
return 0;
}
/* ---------- Task Collector Thread implementation ---------- */
static void sas_queue(struct sas_ha_struct *sas_ha)
{
struct scsi_core *core = &sas_ha->core;
unsigned long flags;
LIST_HEAD(q);
int can_queue;
int res;
struct sas_internal *i = to_sas_internal(core->shost->transportt);
spin_lock_irqsave(&core->task_queue_lock, flags);
while (!core->queue_thread_kill &&
!list_empty(&core->task_queue)) {
can_queue = sas_ha->lldd_queue_size - core->task_queue_size;
if (can_queue >= 0) {
can_queue = core->task_queue_size;
list_splice_init(&core->task_queue, &q);
} else {
struct list_head *a, *n;
can_queue = sas_ha->lldd_queue_size;
list_for_each_safe(a, n, &core->task_queue) {
list_move_tail(a, &q);
if (--can_queue == 0)
break;
}
can_queue = sas_ha->lldd_queue_size;
}
core->task_queue_size -= can_queue;
spin_unlock_irqrestore(&core->task_queue_lock, flags);
{
struct sas_task *task = list_entry(q.next,
struct sas_task,
list);
list_del_init(&q);
res = i->dft->lldd_execute_task(task, can_queue,
GFP_KERNEL);
if (unlikely(res))
__list_add(&q, task->list.prev, &task->list);
}
spin_lock_irqsave(&core->task_queue_lock, flags);
if (res) {
list_splice_init(&q, &core->task_queue); /*at head*/
core->task_queue_size += can_queue;
}
}
spin_unlock_irqrestore(&core->task_queue_lock, flags);
}
static DECLARE_COMPLETION(queue_th_comp);
/**
* sas_queue_thread -- The Task Collector thread
* @_sas_ha: pointer to struct sas_ha
*/
static int sas_queue_thread(void *_sas_ha)
{
struct sas_ha_struct *sas_ha = _sas_ha;
struct scsi_core *core = &sas_ha->core;
daemonize("sas_queue_%d", core->shost->host_no);
current->flags |= PF_NOFREEZE;
complete(&queue_th_comp);
while (1) {
down_interruptible(&core->queue_thread_sema);
sas_queue(sas_ha);
if (core->queue_thread_kill)
break;
}
complete(&queue_th_comp);
return 0;
}
int sas_init_queue(struct sas_ha_struct *sas_ha)
{
int res;
struct scsi_core *core = &sas_ha->core;
spin_lock_init(&core->task_queue_lock);
core->task_queue_size = 0;
INIT_LIST_HEAD(&core->task_queue);
init_MUTEX_LOCKED(&core->queue_thread_sema);
res = kernel_thread(sas_queue_thread, sas_ha, 0);
if (res >= 0)
wait_for_completion(&queue_th_comp);
return res < 0 ? res : 0;
}
void sas_shutdown_queue(struct sas_ha_struct *sas_ha)
{
unsigned long flags;
struct scsi_core *core = &sas_ha->core;
struct sas_task *task, *n;
init_completion(&queue_th_comp);
core->queue_thread_kill = 1;
up(&core->queue_thread_sema);
wait_for_completion(&queue_th_comp);
if (!list_empty(&core->task_queue))
SAS_DPRINTK("HA: %llx: scsi core task queue is NOT empty!?\n",
SAS_ADDR(sas_ha->sas_addr));
spin_lock_irqsave(&core->task_queue_lock, flags);
list_for_each_entry_safe(task, n, &core->task_queue, list) {
struct scsi_cmnd *cmd = task->uldd_task;
list_del_init(&task->list);
ASSIGN_SAS_TASK(cmd, NULL);
sas_free_task(task);
cmd->result = DID_ABORT << 16;
cmd->scsi_done(cmd);
}
spin_unlock_irqrestore(&core->task_queue_lock, flags);
}
static int do_sas_task_abort(struct sas_task *task)
{
struct scsi_cmnd *sc = task->uldd_task;
struct sas_internal *si =
to_sas_internal(task->dev->port->ha->core.shost->transportt);
unsigned long flags;
int res;
spin_lock_irqsave(&task->task_state_lock, flags);
if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("%s: Task %p already aborted.\n", __FUNCTION__,
task);
return 0;
}
task->task_state_flags |= SAS_TASK_INITIATOR_ABORTED;
if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
task->task_state_flags |= SAS_TASK_STATE_ABORTED;
spin_unlock_irqrestore(&task->task_state_lock, flags);
if (!si->dft->lldd_abort_task)
return -ENODEV;
res = si->dft->lldd_abort_task(task);
if ((task->task_state_flags & SAS_TASK_STATE_DONE) ||
(res == TMF_RESP_FUNC_COMPLETE))
{
/* SMP commands don't have scsi_cmds(?) */
if (!sc) {
task->task_done(task);
return 0;
}
scsi_req_abort_cmd(sc);
scsi_schedule_eh(sc->device->host);
return 0;
}
spin_lock_irqsave(&task->task_state_lock, flags);
task->task_state_flags &= ~SAS_TASK_INITIATOR_ABORTED;
if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
task->task_state_flags &= ~SAS_TASK_STATE_ABORTED;
spin_unlock_irqrestore(&task->task_state_lock, flags);
return -EAGAIN;
}
void sas_task_abort(struct work_struct *work)
{
struct sas_task *task =
container_of(work, struct sas_task, abort_work);
int i;
for (i = 0; i < 5; i++)
if (!do_sas_task_abort(task))
return;
SAS_DPRINTK("%s: Could not kill task!\n", __FUNCTION__);
}
EXPORT_SYMBOL_GPL(sas_queuecommand);
EXPORT_SYMBOL_GPL(sas_target_alloc);
EXPORT_SYMBOL_GPL(sas_slave_configure);
EXPORT_SYMBOL_GPL(sas_slave_destroy);
EXPORT_SYMBOL_GPL(sas_change_queue_depth);
EXPORT_SYMBOL_GPL(sas_change_queue_type);
EXPORT_SYMBOL_GPL(sas_bios_param);
EXPORT_SYMBOL_GPL(sas_task_abort);
EXPORT_SYMBOL_GPL(sas_phy_reset);
EXPORT_SYMBOL_GPL(sas_phy_enable);