You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
462 lines
12 KiB
462 lines
12 KiB
/*
|
|
* hosts.c Copyright (C) 1992 Drew Eckhardt
|
|
* Copyright (C) 1993, 1994, 1995 Eric Youngdale
|
|
* Copyright (C) 2002-2003 Christoph Hellwig
|
|
*
|
|
* mid to lowlevel SCSI driver interface
|
|
* Initial versions: Drew Eckhardt
|
|
* Subsequent revisions: Eric Youngdale
|
|
*
|
|
* <drew@colorado.edu>
|
|
*
|
|
* Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
|
|
* Added QLOGIC QLA1280 SCSI controller kernel host support.
|
|
* August 4, 1999 Fred Lewis, Intel DuPont
|
|
*
|
|
* Updated to reflect the new initialization scheme for the higher
|
|
* level of scsi drivers (sd/sr/st)
|
|
* September 17, 2000 Torben Mathiasen <tmm@image.dk>
|
|
*
|
|
* Restructured scsi_host lists and associated functions.
|
|
* September 04, 2002 Mike Anderson (andmike@us.ibm.com)
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/init.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/transport_class.h>
|
|
|
|
#include <scsi/scsi_device.h>
|
|
#include <scsi/scsi_host.h>
|
|
#include <scsi/scsi_transport.h>
|
|
|
|
#include "scsi_priv.h"
|
|
#include "scsi_logging.h"
|
|
|
|
|
|
static int scsi_host_next_hn; /* host_no for next new host */
|
|
|
|
|
|
static void scsi_host_cls_release(struct class_device *class_dev)
|
|
{
|
|
put_device(&class_to_shost(class_dev)->shost_gendev);
|
|
}
|
|
|
|
static struct class shost_class = {
|
|
.name = "scsi_host",
|
|
.release = scsi_host_cls_release,
|
|
};
|
|
|
|
/**
|
|
* scsi_host_cancel - cancel outstanding IO to this host
|
|
* @shost: pointer to struct Scsi_Host
|
|
* recovery: recovery requested to run.
|
|
**/
|
|
void scsi_host_cancel(struct Scsi_Host *shost, int recovery)
|
|
{
|
|
struct scsi_device *sdev;
|
|
|
|
set_bit(SHOST_CANCEL, &shost->shost_state);
|
|
shost_for_each_device(sdev, shost) {
|
|
scsi_device_cancel(sdev, recovery);
|
|
}
|
|
wait_event(shost->host_wait, (!test_bit(SHOST_RECOVERY,
|
|
&shost->shost_state)));
|
|
}
|
|
|
|
/**
|
|
* scsi_remove_host - remove a scsi host
|
|
* @shost: a pointer to a scsi host to remove
|
|
**/
|
|
void scsi_remove_host(struct Scsi_Host *shost)
|
|
{
|
|
scsi_forget_host(shost);
|
|
scsi_host_cancel(shost, 0);
|
|
scsi_proc_host_rm(shost);
|
|
|
|
set_bit(SHOST_DEL, &shost->shost_state);
|
|
|
|
transport_unregister_device(&shost->shost_gendev);
|
|
class_device_unregister(&shost->shost_classdev);
|
|
device_del(&shost->shost_gendev);
|
|
}
|
|
EXPORT_SYMBOL(scsi_remove_host);
|
|
|
|
/**
|
|
* scsi_add_host - add a scsi host
|
|
* @shost: scsi host pointer to add
|
|
* @dev: a struct device of type scsi class
|
|
*
|
|
* Return value:
|
|
* 0 on success / != 0 for error
|
|
**/
|
|
int scsi_add_host(struct Scsi_Host *shost, struct device *dev)
|
|
{
|
|
struct scsi_host_template *sht = shost->hostt;
|
|
int error = -EINVAL;
|
|
|
|
printk(KERN_INFO "scsi%d : %s\n", shost->host_no,
|
|
sht->info ? sht->info(shost) : sht->name);
|
|
|
|
if (!shost->can_queue) {
|
|
printk(KERN_ERR "%s: can_queue = 0 no longer supported\n",
|
|
sht->name);
|
|
goto out;
|
|
}
|
|
|
|
if (!shost->shost_gendev.parent)
|
|
shost->shost_gendev.parent = dev ? dev : &platform_bus;
|
|
|
|
error = device_add(&shost->shost_gendev);
|
|
if (error)
|
|
goto out;
|
|
|
|
set_bit(SHOST_ADD, &shost->shost_state);
|
|
get_device(shost->shost_gendev.parent);
|
|
|
|
error = class_device_add(&shost->shost_classdev);
|
|
if (error)
|
|
goto out_del_gendev;
|
|
|
|
get_device(&shost->shost_gendev);
|
|
|
|
if (shost->transportt->host_size &&
|
|
(shost->shost_data = kmalloc(shost->transportt->host_size,
|
|
GFP_KERNEL)) == NULL)
|
|
goto out_del_classdev;
|
|
|
|
if (shost->transportt->create_work_queue) {
|
|
snprintf(shost->work_q_name, KOBJ_NAME_LEN, "scsi_wq_%d",
|
|
shost->host_no);
|
|
shost->work_q = create_singlethread_workqueue(
|
|
shost->work_q_name);
|
|
if (!shost->work_q)
|
|
goto out_free_shost_data;
|
|
}
|
|
|
|
error = scsi_sysfs_add_host(shost);
|
|
if (error)
|
|
goto out_destroy_host;
|
|
|
|
scsi_proc_host_add(shost);
|
|
return error;
|
|
|
|
out_destroy_host:
|
|
if (shost->work_q)
|
|
destroy_workqueue(shost->work_q);
|
|
out_free_shost_data:
|
|
kfree(shost->shost_data);
|
|
out_del_classdev:
|
|
class_device_del(&shost->shost_classdev);
|
|
out_del_gendev:
|
|
device_del(&shost->shost_gendev);
|
|
out:
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL(scsi_add_host);
|
|
|
|
static void scsi_host_dev_release(struct device *dev)
|
|
{
|
|
struct Scsi_Host *shost = dev_to_shost(dev);
|
|
struct device *parent = dev->parent;
|
|
|
|
if (shost->ehandler) {
|
|
DECLARE_COMPLETION(sem);
|
|
shost->eh_notify = &sem;
|
|
shost->eh_kill = 1;
|
|
up(shost->eh_wait);
|
|
wait_for_completion(&sem);
|
|
shost->eh_notify = NULL;
|
|
}
|
|
|
|
if (shost->work_q)
|
|
destroy_workqueue(shost->work_q);
|
|
|
|
scsi_proc_hostdir_rm(shost->hostt);
|
|
scsi_destroy_command_freelist(shost);
|
|
kfree(shost->shost_data);
|
|
|
|
/*
|
|
* Some drivers (eg aha1542) do scsi_register()/scsi_unregister()
|
|
* during probing without performing a scsi_set_device() in between.
|
|
* In this case dev->parent is NULL.
|
|
*/
|
|
if (parent)
|
|
put_device(parent);
|
|
kfree(shost);
|
|
}
|
|
|
|
/**
|
|
* scsi_host_alloc - register a scsi host adapter instance.
|
|
* @sht: pointer to scsi host template
|
|
* @privsize: extra bytes to allocate for driver
|
|
*
|
|
* Note:
|
|
* Allocate a new Scsi_Host and perform basic initialization.
|
|
* The host is not published to the scsi midlayer until scsi_add_host
|
|
* is called.
|
|
*
|
|
* Return value:
|
|
* Pointer to a new Scsi_Host
|
|
**/
|
|
struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
|
|
{
|
|
struct Scsi_Host *shost;
|
|
int gfp_mask = GFP_KERNEL, rval;
|
|
DECLARE_COMPLETION(complete);
|
|
|
|
if (sht->unchecked_isa_dma && privsize)
|
|
gfp_mask |= __GFP_DMA;
|
|
|
|
/* Check to see if this host has any error handling facilities */
|
|
if (!sht->eh_strategy_handler && !sht->eh_abort_handler &&
|
|
!sht->eh_device_reset_handler && !sht->eh_bus_reset_handler &&
|
|
!sht->eh_host_reset_handler) {
|
|
printk(KERN_ERR "ERROR: SCSI host `%s' has no error handling\n"
|
|
"ERROR: This is not a safe way to run your "
|
|
"SCSI host\n"
|
|
"ERROR: The error handling must be added to "
|
|
"this driver\n", sht->proc_name);
|
|
dump_stack();
|
|
}
|
|
|
|
shost = kmalloc(sizeof(struct Scsi_Host) + privsize, gfp_mask);
|
|
if (!shost)
|
|
return NULL;
|
|
memset(shost, 0, sizeof(struct Scsi_Host) + privsize);
|
|
|
|
spin_lock_init(&shost->default_lock);
|
|
scsi_assign_lock(shost, &shost->default_lock);
|
|
INIT_LIST_HEAD(&shost->__devices);
|
|
INIT_LIST_HEAD(&shost->__targets);
|
|
INIT_LIST_HEAD(&shost->eh_cmd_q);
|
|
INIT_LIST_HEAD(&shost->starved_list);
|
|
init_waitqueue_head(&shost->host_wait);
|
|
|
|
init_MUTEX(&shost->scan_mutex);
|
|
|
|
shost->host_no = scsi_host_next_hn++; /* XXX(hch): still racy */
|
|
shost->dma_channel = 0xff;
|
|
|
|
/* These three are default values which can be overridden */
|
|
shost->max_channel = 0;
|
|
shost->max_id = 8;
|
|
shost->max_lun = 8;
|
|
|
|
/* Give each shost a default transportt */
|
|
shost->transportt = &blank_transport_template;
|
|
|
|
/*
|
|
* All drivers right now should be able to handle 12 byte
|
|
* commands. Every so often there are requests for 16 byte
|
|
* commands, but individual low-level drivers need to certify that
|
|
* they actually do something sensible with such commands.
|
|
*/
|
|
shost->max_cmd_len = 12;
|
|
shost->hostt = sht;
|
|
shost->this_id = sht->this_id;
|
|
shost->can_queue = sht->can_queue;
|
|
shost->sg_tablesize = sht->sg_tablesize;
|
|
shost->cmd_per_lun = sht->cmd_per_lun;
|
|
shost->unchecked_isa_dma = sht->unchecked_isa_dma;
|
|
shost->use_clustering = sht->use_clustering;
|
|
shost->ordered_flush = sht->ordered_flush;
|
|
shost->ordered_tag = sht->ordered_tag;
|
|
|
|
/*
|
|
* hosts/devices that do queueing must support ordered tags
|
|
*/
|
|
if (shost->can_queue > 1 && shost->ordered_flush) {
|
|
printk(KERN_ERR "scsi: ordered flushes don't support queueing\n");
|
|
shost->ordered_flush = 0;
|
|
}
|
|
|
|
if (sht->max_host_blocked)
|
|
shost->max_host_blocked = sht->max_host_blocked;
|
|
else
|
|
shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED;
|
|
|
|
/*
|
|
* If the driver imposes no hard sector transfer limit, start at
|
|
* machine infinity initially.
|
|
*/
|
|
if (sht->max_sectors)
|
|
shost->max_sectors = sht->max_sectors;
|
|
else
|
|
shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS;
|
|
|
|
/*
|
|
* assume a 4GB boundary, if not set
|
|
*/
|
|
if (sht->dma_boundary)
|
|
shost->dma_boundary = sht->dma_boundary;
|
|
else
|
|
shost->dma_boundary = 0xffffffff;
|
|
|
|
rval = scsi_setup_command_freelist(shost);
|
|
if (rval)
|
|
goto fail_kfree;
|
|
|
|
device_initialize(&shost->shost_gendev);
|
|
snprintf(shost->shost_gendev.bus_id, BUS_ID_SIZE, "host%d",
|
|
shost->host_no);
|
|
shost->shost_gendev.release = scsi_host_dev_release;
|
|
|
|
class_device_initialize(&shost->shost_classdev);
|
|
shost->shost_classdev.dev = &shost->shost_gendev;
|
|
shost->shost_classdev.class = &shost_class;
|
|
snprintf(shost->shost_classdev.class_id, BUS_ID_SIZE, "host%d",
|
|
shost->host_no);
|
|
|
|
shost->eh_notify = &complete;
|
|
rval = kernel_thread(scsi_error_handler, shost, 0);
|
|
if (rval < 0)
|
|
goto fail_destroy_freelist;
|
|
wait_for_completion(&complete);
|
|
shost->eh_notify = NULL;
|
|
|
|
scsi_proc_hostdir_add(shost->hostt);
|
|
return shost;
|
|
|
|
fail_destroy_freelist:
|
|
scsi_destroy_command_freelist(shost);
|
|
fail_kfree:
|
|
kfree(shost);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_alloc);
|
|
|
|
struct Scsi_Host *scsi_register(struct scsi_host_template *sht, int privsize)
|
|
{
|
|
struct Scsi_Host *shost = scsi_host_alloc(sht, privsize);
|
|
|
|
if (!sht->detect) {
|
|
printk(KERN_WARNING "scsi_register() called on new-style "
|
|
"template for driver %s\n", sht->name);
|
|
dump_stack();
|
|
}
|
|
|
|
if (shost)
|
|
list_add_tail(&shost->sht_legacy_list, &sht->legacy_hosts);
|
|
return shost;
|
|
}
|
|
EXPORT_SYMBOL(scsi_register);
|
|
|
|
void scsi_unregister(struct Scsi_Host *shost)
|
|
{
|
|
list_del(&shost->sht_legacy_list);
|
|
scsi_host_put(shost);
|
|
}
|
|
EXPORT_SYMBOL(scsi_unregister);
|
|
|
|
/**
|
|
* scsi_host_lookup - get a reference to a Scsi_Host by host no
|
|
*
|
|
* @hostnum: host number to locate
|
|
*
|
|
* Return value:
|
|
* A pointer to located Scsi_Host or NULL.
|
|
**/
|
|
struct Scsi_Host *scsi_host_lookup(unsigned short hostnum)
|
|
{
|
|
struct class *class = &shost_class;
|
|
struct class_device *cdev;
|
|
struct Scsi_Host *shost = ERR_PTR(-ENXIO), *p;
|
|
|
|
down_read(&class->subsys.rwsem);
|
|
list_for_each_entry(cdev, &class->children, node) {
|
|
p = class_to_shost(cdev);
|
|
if (p->host_no == hostnum) {
|
|
shost = scsi_host_get(p);
|
|
break;
|
|
}
|
|
}
|
|
up_read(&class->subsys.rwsem);
|
|
|
|
return shost;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_lookup);
|
|
|
|
/**
|
|
* scsi_host_get - inc a Scsi_Host ref count
|
|
* @shost: Pointer to Scsi_Host to inc.
|
|
**/
|
|
struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost)
|
|
{
|
|
if (test_bit(SHOST_DEL, &shost->shost_state) ||
|
|
!get_device(&shost->shost_gendev))
|
|
return NULL;
|
|
return shost;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_get);
|
|
|
|
/**
|
|
* scsi_host_put - dec a Scsi_Host ref count
|
|
* @shost: Pointer to Scsi_Host to dec.
|
|
**/
|
|
void scsi_host_put(struct Scsi_Host *shost)
|
|
{
|
|
put_device(&shost->shost_gendev);
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_put);
|
|
|
|
int scsi_init_hosts(void)
|
|
{
|
|
return class_register(&shost_class);
|
|
}
|
|
|
|
void scsi_exit_hosts(void)
|
|
{
|
|
class_unregister(&shost_class);
|
|
}
|
|
|
|
int scsi_is_host_device(const struct device *dev)
|
|
{
|
|
return dev->release == scsi_host_dev_release;
|
|
}
|
|
EXPORT_SYMBOL(scsi_is_host_device);
|
|
|
|
/**
|
|
* scsi_queue_work - Queue work to the Scsi_Host workqueue.
|
|
* @shost: Pointer to Scsi_Host.
|
|
* @work: Work to queue for execution.
|
|
*
|
|
* Return value:
|
|
* 0 on success / != 0 for error
|
|
**/
|
|
int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work)
|
|
{
|
|
if (unlikely(!shost->work_q)) {
|
|
printk(KERN_ERR
|
|
"ERROR: Scsi host '%s' attempted to queue scsi-work, "
|
|
"when no workqueue created.\n", shost->hostt->name);
|
|
dump_stack();
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
return queue_work(shost->work_q, work);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_queue_work);
|
|
|
|
/**
|
|
* scsi_flush_work - Flush a Scsi_Host's workqueue.
|
|
* @shost: Pointer to Scsi_Host.
|
|
**/
|
|
void scsi_flush_work(struct Scsi_Host *shost)
|
|
{
|
|
if (!shost->work_q) {
|
|
printk(KERN_ERR
|
|
"ERROR: Scsi host '%s' attempted to flush scsi-work, "
|
|
"when no workqueue created.\n", shost->hostt->name);
|
|
dump_stack();
|
|
return;
|
|
}
|
|
|
|
flush_workqueue(shost->work_q);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_flush_work);
|
|
|