linux/drivers/scsi/scsi_transport_fc.c
James Smart aedf349773 [SCSI] FC transport: fixes for workq deadlocks
As previously reported via Michael Reed, the FC transport took a hit
in 2.6.15 (perhaps a little earlier) when we solved a recursion error.
There are 2 deadlocks occurring:
- With scan and the delete items sharing the same workq, flushing the
  workq for the delete code was getting it stalled behind a very long
  running scan code path.
- There's a deadlock where scsi_remove_target() has to sit behind
  scsi_scan_target() due to contention over the scan_lock().

This patch resolves the 1st deadlock and significantly reduces the
odds of the second. So far, we have only replicated the 2nd deadlock
on a highly-parallel SMP system. More on the 2nd deadlock in a following
email.

This patch reworks the transport to:
- Only use the scsi host workq for scanning
- Use 2 other workq's internally. One for deletions, the other for
  scheduled deletions. Originally, we tried this with a single workq,
  but the occassional flushes of the scheduled queues was hitting the
  second deadlock with a slightly higher frequency. In the future, we'll
  look at the LLDD's and the transport to see if we can get rid of this
  extra overhead.
- When moving to the other workq's we tightened up some object states
  and some lock handling.
- Properly syncs adds/deletes
- minor code cleanups
  - directly reference fc_host_attrs, rather than through attribute
    macros
  - flush the right workq on delayed work cancel failures.

Large kudos to Michael Reed who has been working this issue for the last
month.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-13 13:25:16 -05:00

2077 lines
63 KiB
C

/*
* FiberChannel transport specific attributes exported to sysfs.
*
* Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved.
*
* 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
*
* ========
*
* Copyright (C) 2004-2005 James Smart, Emulex Corporation
* Rewrite for host, target, device, and remote port attributes,
* statistics, and service functions...
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h> /* workqueue stuff, HZ */
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_fc.h>
#include <scsi/scsi_cmnd.h>
#include "scsi_priv.h"
static int fc_queue_work(struct Scsi_Host *, struct work_struct *);
/*
* Redefine so that we can have same named attributes in the
* sdev/starget/host objects.
*/
#define FC_CLASS_DEVICE_ATTR(_prefix,_name,_mode,_show,_store) \
struct class_device_attribute class_device_attr_##_prefix##_##_name = \
__ATTR(_name,_mode,_show,_store)
#define fc_enum_name_search(title, table_type, table) \
static const char *get_fc_##title##_name(enum table_type table_key) \
{ \
int i; \
char *name = NULL; \
\
for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) { \
if (table[i].value == table_key) { \
name = table[i].name; \
break; \
} \
} \
return name; \
}
#define fc_enum_name_match(title, table_type, table) \
static int get_fc_##title##_match(const char *table_key, \
enum table_type *value) \
{ \
int i; \
\
for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) { \
if (strncmp(table_key, table[i].name, \
table[i].matchlen) == 0) { \
*value = table[i].value; \
return 0; /* success */ \
} \
} \
return 1; /* failure */ \
}
/* Convert fc_port_type values to ascii string name */
static struct {
enum fc_port_type value;
char *name;
} fc_port_type_names[] = {
{ FC_PORTTYPE_UNKNOWN, "Unknown" },
{ FC_PORTTYPE_OTHER, "Other" },
{ FC_PORTTYPE_NOTPRESENT, "Not Present" },
{ FC_PORTTYPE_NPORT, "NPort (fabric via point-to-point)" },
{ FC_PORTTYPE_NLPORT, "NLPort (fabric via loop)" },
{ FC_PORTTYPE_LPORT, "LPort (private loop)" },
{ FC_PORTTYPE_PTP, "Point-To-Point (direct nport connection" },
};
fc_enum_name_search(port_type, fc_port_type, fc_port_type_names)
#define FC_PORTTYPE_MAX_NAMELEN 50
/* Convert fc_port_state values to ascii string name */
static struct {
enum fc_port_state value;
char *name;
} fc_port_state_names[] = {
{ FC_PORTSTATE_UNKNOWN, "Unknown" },
{ FC_PORTSTATE_NOTPRESENT, "Not Present" },
{ FC_PORTSTATE_ONLINE, "Online" },
{ FC_PORTSTATE_OFFLINE, "Offline" },
{ FC_PORTSTATE_BLOCKED, "Blocked" },
{ FC_PORTSTATE_BYPASSED, "Bypassed" },
{ FC_PORTSTATE_DIAGNOSTICS, "Diagnostics" },
{ FC_PORTSTATE_LINKDOWN, "Linkdown" },
{ FC_PORTSTATE_ERROR, "Error" },
{ FC_PORTSTATE_LOOPBACK, "Loopback" },
{ FC_PORTSTATE_DELETED, "Deleted" },
};
fc_enum_name_search(port_state, fc_port_state, fc_port_state_names)
#define FC_PORTSTATE_MAX_NAMELEN 20
/* Convert fc_tgtid_binding_type values to ascii string name */
static const struct {
enum fc_tgtid_binding_type value;
char *name;
int matchlen;
} fc_tgtid_binding_type_names[] = {
{ FC_TGTID_BIND_NONE, "none", 4 },
{ FC_TGTID_BIND_BY_WWPN, "wwpn (World Wide Port Name)", 4 },
{ FC_TGTID_BIND_BY_WWNN, "wwnn (World Wide Node Name)", 4 },
{ FC_TGTID_BIND_BY_ID, "port_id (FC Address)", 7 },
};
fc_enum_name_search(tgtid_bind_type, fc_tgtid_binding_type,
fc_tgtid_binding_type_names)
fc_enum_name_match(tgtid_bind_type, fc_tgtid_binding_type,
fc_tgtid_binding_type_names)
#define FC_BINDTYPE_MAX_NAMELEN 30
#define fc_bitfield_name_search(title, table) \
static ssize_t \
get_fc_##title##_names(u32 table_key, char *buf) \
{ \
char *prefix = ""; \
ssize_t len = 0; \
int i; \
\
for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) { \
if (table[i].value & table_key) { \
len += sprintf(buf + len, "%s%s", \
prefix, table[i].name); \
prefix = ", "; \
} \
} \
len += sprintf(buf + len, "\n"); \
return len; \
}
/* Convert FC_COS bit values to ascii string name */
static const struct {
u32 value;
char *name;
} fc_cos_names[] = {
{ FC_COS_CLASS1, "Class 1" },
{ FC_COS_CLASS2, "Class 2" },
{ FC_COS_CLASS3, "Class 3" },
{ FC_COS_CLASS4, "Class 4" },
{ FC_COS_CLASS6, "Class 6" },
};
fc_bitfield_name_search(cos, fc_cos_names)
/* Convert FC_PORTSPEED bit values to ascii string name */
static const struct {
u32 value;
char *name;
} fc_port_speed_names[] = {
{ FC_PORTSPEED_1GBIT, "1 Gbit" },
{ FC_PORTSPEED_2GBIT, "2 Gbit" },
{ FC_PORTSPEED_4GBIT, "4 Gbit" },
{ FC_PORTSPEED_10GBIT, "10 Gbit" },
{ FC_PORTSPEED_NOT_NEGOTIATED, "Not Negotiated" },
};
fc_bitfield_name_search(port_speed, fc_port_speed_names)
static int
show_fc_fc4s (char *buf, u8 *fc4_list)
{
int i, len=0;
for (i = 0; i < FC_FC4_LIST_SIZE; i++, fc4_list++)
len += sprintf(buf + len , "0x%02x ", *fc4_list);
len += sprintf(buf + len, "\n");
return len;
}
/* Convert FC_RPORT_ROLE bit values to ascii string name */
static const struct {
u32 value;
char *name;
} fc_remote_port_role_names[] = {
{ FC_RPORT_ROLE_FCP_TARGET, "FCP Target" },
{ FC_RPORT_ROLE_FCP_INITIATOR, "FCP Initiator" },
{ FC_RPORT_ROLE_IP_PORT, "IP Port" },
};
fc_bitfield_name_search(remote_port_roles, fc_remote_port_role_names)
/*
* Define roles that are specific to port_id. Values are relative to ROLE_MASK.
*/
#define FC_WELLKNOWN_PORTID_MASK 0xfffff0
#define FC_WELLKNOWN_ROLE_MASK 0x00000f
#define FC_FPORT_PORTID 0x00000e
#define FC_FABCTLR_PORTID 0x00000d
#define FC_DIRSRVR_PORTID 0x00000c
#define FC_TIMESRVR_PORTID 0x00000b
#define FC_MGMTSRVR_PORTID 0x00000a
static void fc_timeout_deleted_rport(void *data);
static void fc_scsi_scan_rport(void *data);
/*
* Attribute counts pre object type...
* Increase these values if you add attributes
*/
#define FC_STARGET_NUM_ATTRS 3
#define FC_RPORT_NUM_ATTRS 9
#define FC_HOST_NUM_ATTRS 17
struct fc_internal {
struct scsi_transport_template t;
struct fc_function_template *f;
/*
* For attributes : each object has :
* An array of the actual attributes structures
* An array of null-terminated pointers to the attribute
* structures - used for mid-layer interaction.
*
* The attribute containers for the starget and host are are
* part of the midlayer. As the remote port is specific to the
* fc transport, we must provide the attribute container.
*/
struct class_device_attribute private_starget_attrs[
FC_STARGET_NUM_ATTRS];
struct class_device_attribute *starget_attrs[FC_STARGET_NUM_ATTRS + 1];
struct class_device_attribute private_host_attrs[FC_HOST_NUM_ATTRS];
struct class_device_attribute *host_attrs[FC_HOST_NUM_ATTRS + 1];
struct transport_container rport_attr_cont;
struct class_device_attribute private_rport_attrs[FC_RPORT_NUM_ATTRS];
struct class_device_attribute *rport_attrs[FC_RPORT_NUM_ATTRS + 1];
};
#define to_fc_internal(tmpl) container_of(tmpl, struct fc_internal, t)
static int fc_target_setup(struct transport_container *tc, struct device *dev,
struct class_device *cdev)
{
struct scsi_target *starget = to_scsi_target(dev);
struct fc_rport *rport = starget_to_rport(starget);
/*
* if parent is remote port, use values from remote port.
* Otherwise, this host uses the fc_transport, but not the
* remote port interface. As such, initialize to known non-values.
*/
if (rport) {
fc_starget_node_name(starget) = rport->node_name;
fc_starget_port_name(starget) = rport->port_name;
fc_starget_port_id(starget) = rport->port_id;
} else {
fc_starget_node_name(starget) = -1;
fc_starget_port_name(starget) = -1;
fc_starget_port_id(starget) = -1;
}
return 0;
}
static DECLARE_TRANSPORT_CLASS(fc_transport_class,
"fc_transport",
fc_target_setup,
NULL,
NULL);
static int fc_host_setup(struct transport_container *tc, struct device *dev,
struct class_device *cdev)
{
struct Scsi_Host *shost = dev_to_shost(dev);
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
/*
* Set default values easily detected by the midlayer as
* failure cases. The scsi lldd is responsible for initializing
* all transport attributes to valid values per host.
*/
fc_host->node_name = -1;
fc_host->port_name = -1;
fc_host->permanent_port_name = -1;
fc_host->supported_classes = FC_COS_UNSPECIFIED;
memset(fc_host->supported_fc4s, 0,
sizeof(fc_host->supported_fc4s));
memset(fc_host->symbolic_name, 0,
sizeof(fc_host->symbolic_name));
fc_host->supported_speeds = FC_PORTSPEED_UNKNOWN;
fc_host->maxframe_size = -1;
memset(fc_host->serial_number, 0,
sizeof(fc_host->serial_number));
fc_host->port_id = -1;
fc_host->port_type = FC_PORTTYPE_UNKNOWN;
fc_host->port_state = FC_PORTSTATE_UNKNOWN;
memset(fc_host->active_fc4s, 0,
sizeof(fc_host->active_fc4s));
fc_host->speed = FC_PORTSPEED_UNKNOWN;
fc_host->fabric_name = -1;
fc_host->tgtid_bind_type = FC_TGTID_BIND_BY_WWPN;
INIT_LIST_HEAD(&fc_host->rports);
INIT_LIST_HEAD(&fc_host->rport_bindings);
fc_host->next_rport_number = 0;
fc_host->next_target_id = 0;
snprintf(fc_host->work_q_name, KOBJ_NAME_LEN, "fc_wq_%d",
shost->host_no);
fc_host->work_q = create_singlethread_workqueue(
fc_host->work_q_name);
if (!fc_host->work_q)
return -ENOMEM;
snprintf(fc_host->devloss_work_q_name, KOBJ_NAME_LEN, "fc_dl_%d",
shost->host_no);
fc_host->devloss_work_q = create_singlethread_workqueue(
fc_host->devloss_work_q_name);
if (!fc_host->devloss_work_q) {
destroy_workqueue(fc_host->work_q);
fc_host->work_q = NULL;
return -ENOMEM;
}
return 0;
}
static DECLARE_TRANSPORT_CLASS(fc_host_class,
"fc_host",
fc_host_setup,
NULL,
NULL);
/*
* Setup and Remove actions for remote ports are handled
* in the service functions below.
*/
static DECLARE_TRANSPORT_CLASS(fc_rport_class,
"fc_remote_ports",
NULL,
NULL,
NULL);
/*
* Module Parameters
*/
/*
* dev_loss_tmo: the default number of seconds that the FC transport
* should insulate the loss of a remote port.
* The maximum will be capped by the value of SCSI_DEVICE_BLOCK_MAX_TIMEOUT.
*/
static unsigned int fc_dev_loss_tmo = SCSI_DEVICE_BLOCK_MAX_TIMEOUT;
module_param_named(dev_loss_tmo, fc_dev_loss_tmo, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(dev_loss_tmo,
"Maximum number of seconds that the FC transport should"
" insulate the loss of a remote port. Once this value is"
" exceeded, the scsi target is removed. Value should be"
" between 1 and SCSI_DEVICE_BLOCK_MAX_TIMEOUT.");
static __init int fc_transport_init(void)
{
int error = transport_class_register(&fc_host_class);
if (error)
return error;
error = transport_class_register(&fc_rport_class);
if (error)
return error;
return transport_class_register(&fc_transport_class);
}
static void __exit fc_transport_exit(void)
{
transport_class_unregister(&fc_transport_class);
transport_class_unregister(&fc_rport_class);
transport_class_unregister(&fc_host_class);
}
/*
* FC Remote Port Attribute Management
*/
#define fc_rport_show_function(field, format_string, sz, cast) \
static ssize_t \
show_fc_rport_##field (struct class_device *cdev, char *buf) \
{ \
struct fc_rport *rport = transport_class_to_rport(cdev); \
struct Scsi_Host *shost = rport_to_shost(rport); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
if ((i->f->get_rport_##field) && \
!((rport->port_state == FC_PORTSTATE_BLOCKED) || \
(rport->port_state == FC_PORTSTATE_DELETED) || \
(rport->port_state == FC_PORTSTATE_NOTPRESENT))) \
i->f->get_rport_##field(rport); \
return snprintf(buf, sz, format_string, cast rport->field); \
}
#define fc_rport_store_function(field) \
static ssize_t \
store_fc_rport_##field(struct class_device *cdev, const char *buf, \
size_t count) \
{ \
int val; \
struct fc_rport *rport = transport_class_to_rport(cdev); \
struct Scsi_Host *shost = rport_to_shost(rport); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
if ((rport->port_state == FC_PORTSTATE_BLOCKED) || \
(rport->port_state == FC_PORTSTATE_DELETED) || \
(rport->port_state == FC_PORTSTATE_NOTPRESENT)) \
return -EBUSY; \
val = simple_strtoul(buf, NULL, 0); \
i->f->set_rport_##field(rport, val); \
return count; \
}
#define fc_rport_rd_attr(field, format_string, sz) \
fc_rport_show_function(field, format_string, sz, ) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO, \
show_fc_rport_##field, NULL)
#define fc_rport_rd_attr_cast(field, format_string, sz, cast) \
fc_rport_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO, \
show_fc_rport_##field, NULL)
#define fc_rport_rw_attr(field, format_string, sz) \
fc_rport_show_function(field, format_string, sz, ) \
fc_rport_store_function(field) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO | S_IWUSR, \
show_fc_rport_##field, \
store_fc_rport_##field)
#define fc_private_rport_show_function(field, format_string, sz, cast) \
static ssize_t \
show_fc_rport_##field (struct class_device *cdev, char *buf) \
{ \
struct fc_rport *rport = transport_class_to_rport(cdev); \
return snprintf(buf, sz, format_string, cast rport->field); \
}
#define fc_private_rport_rd_attr(field, format_string, sz) \
fc_private_rport_show_function(field, format_string, sz, ) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO, \
show_fc_rport_##field, NULL)
#define fc_private_rport_rd_attr_cast(field, format_string, sz, cast) \
fc_private_rport_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(rport, field, S_IRUGO, \
show_fc_rport_##field, NULL)
#define fc_private_rport_rd_enum_attr(title, maxlen) \
static ssize_t \
show_fc_rport_##title (struct class_device *cdev, char *buf) \
{ \
struct fc_rport *rport = transport_class_to_rport(cdev); \
const char *name; \
name = get_fc_##title##_name(rport->title); \
if (!name) \
return -EINVAL; \
return snprintf(buf, maxlen, "%s\n", name); \
} \
static FC_CLASS_DEVICE_ATTR(rport, title, S_IRUGO, \
show_fc_rport_##title, NULL)
#define SETUP_RPORT_ATTRIBUTE_RD(field) \
i->private_rport_attrs[count] = class_device_attr_rport_##field; \
i->private_rport_attrs[count].attr.mode = S_IRUGO; \
i->private_rport_attrs[count].store = NULL; \
i->rport_attrs[count] = &i->private_rport_attrs[count]; \
if (i->f->show_rport_##field) \
count++
#define SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(field) \
i->private_rport_attrs[count] = class_device_attr_rport_##field; \
i->private_rport_attrs[count].attr.mode = S_IRUGO; \
i->private_rport_attrs[count].store = NULL; \
i->rport_attrs[count] = &i->private_rport_attrs[count]; \
count++
#define SETUP_RPORT_ATTRIBUTE_RW(field) \
i->private_rport_attrs[count] = class_device_attr_rport_##field; \
if (!i->f->set_rport_##field) { \
i->private_rport_attrs[count].attr.mode = S_IRUGO; \
i->private_rport_attrs[count].store = NULL; \
} \
i->rport_attrs[count] = &i->private_rport_attrs[count]; \
if (i->f->show_rport_##field) \
count++
/* The FC Transport Remote Port Attributes: */
/* Fixed Remote Port Attributes */
fc_private_rport_rd_attr(maxframe_size, "%u bytes\n", 20);
static ssize_t
show_fc_rport_supported_classes (struct class_device *cdev, char *buf)
{
struct fc_rport *rport = transport_class_to_rport(cdev);
if (rport->supported_classes == FC_COS_UNSPECIFIED)
return snprintf(buf, 20, "unspecified\n");
return get_fc_cos_names(rport->supported_classes, buf);
}
static FC_CLASS_DEVICE_ATTR(rport, supported_classes, S_IRUGO,
show_fc_rport_supported_classes, NULL);
/* Dynamic Remote Port Attributes */
/*
* dev_loss_tmo attribute
*/
fc_rport_show_function(dev_loss_tmo, "%d\n", 20, )
static ssize_t
store_fc_rport_dev_loss_tmo(struct class_device *cdev, const char *buf,
size_t count)
{
int val;
struct fc_rport *rport = transport_class_to_rport(cdev);
struct Scsi_Host *shost = rport_to_shost(rport);
struct fc_internal *i = to_fc_internal(shost->transportt);
if ((rport->port_state == FC_PORTSTATE_BLOCKED) ||
(rport->port_state == FC_PORTSTATE_DELETED) ||
(rport->port_state == FC_PORTSTATE_NOTPRESENT))
return -EBUSY;
val = simple_strtoul(buf, NULL, 0);
if ((val < 0) || (val > SCSI_DEVICE_BLOCK_MAX_TIMEOUT))
return -EINVAL;
i->f->set_rport_dev_loss_tmo(rport, val);
return count;
}
static FC_CLASS_DEVICE_ATTR(rport, dev_loss_tmo, S_IRUGO | S_IWUSR,
show_fc_rport_dev_loss_tmo, store_fc_rport_dev_loss_tmo);
/* Private Remote Port Attributes */
fc_private_rport_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_private_rport_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_private_rport_rd_attr(port_id, "0x%06x\n", 20);
static ssize_t
show_fc_rport_roles (struct class_device *cdev, char *buf)
{
struct fc_rport *rport = transport_class_to_rport(cdev);
/* identify any roles that are port_id specific */
if ((rport->port_id != -1) &&
(rport->port_id & FC_WELLKNOWN_PORTID_MASK) ==
FC_WELLKNOWN_PORTID_MASK) {
switch (rport->port_id & FC_WELLKNOWN_ROLE_MASK) {
case FC_FPORT_PORTID:
return snprintf(buf, 30, "Fabric Port\n");
case FC_FABCTLR_PORTID:
return snprintf(buf, 30, "Fabric Controller\n");
case FC_DIRSRVR_PORTID:
return snprintf(buf, 30, "Directory Server\n");
case FC_TIMESRVR_PORTID:
return snprintf(buf, 30, "Time Server\n");
case FC_MGMTSRVR_PORTID:
return snprintf(buf, 30, "Management Server\n");
default:
return snprintf(buf, 30, "Unknown Fabric Entity\n");
}
} else {
if (rport->roles == FC_RPORT_ROLE_UNKNOWN)
return snprintf(buf, 20, "unknown\n");
return get_fc_remote_port_roles_names(rport->roles, buf);
}
}
static FC_CLASS_DEVICE_ATTR(rport, roles, S_IRUGO,
show_fc_rport_roles, NULL);
fc_private_rport_rd_enum_attr(port_state, FC_PORTSTATE_MAX_NAMELEN);
fc_private_rport_rd_attr(scsi_target_id, "%d\n", 20);
/*
* FC SCSI Target Attribute Management
*/
/*
* Note: in the target show function we recognize when the remote
* port is in the heirarchy and do not allow the driver to get
* involved in sysfs functions. The driver only gets involved if
* it's the "old" style that doesn't use rports.
*/
#define fc_starget_show_function(field, format_string, sz, cast) \
static ssize_t \
show_fc_starget_##field (struct class_device *cdev, char *buf) \
{ \
struct scsi_target *starget = transport_class_to_starget(cdev); \
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
struct fc_rport *rport = starget_to_rport(starget); \
if (rport) \
fc_starget_##field(starget) = rport->field; \
else if (i->f->get_starget_##field) \
i->f->get_starget_##field(starget); \
return snprintf(buf, sz, format_string, \
cast fc_starget_##field(starget)); \
}
#define fc_starget_rd_attr(field, format_string, sz) \
fc_starget_show_function(field, format_string, sz, ) \
static FC_CLASS_DEVICE_ATTR(starget, field, S_IRUGO, \
show_fc_starget_##field, NULL)
#define fc_starget_rd_attr_cast(field, format_string, sz, cast) \
fc_starget_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(starget, field, S_IRUGO, \
show_fc_starget_##field, NULL)
#define SETUP_STARGET_ATTRIBUTE_RD(field) \
i->private_starget_attrs[count] = class_device_attr_starget_##field; \
i->private_starget_attrs[count].attr.mode = S_IRUGO; \
i->private_starget_attrs[count].store = NULL; \
i->starget_attrs[count] = &i->private_starget_attrs[count]; \
if (i->f->show_starget_##field) \
count++
#define SETUP_STARGET_ATTRIBUTE_RW(field) \
i->private_starget_attrs[count] = class_device_attr_starget_##field; \
if (!i->f->set_starget_##field) { \
i->private_starget_attrs[count].attr.mode = S_IRUGO; \
i->private_starget_attrs[count].store = NULL; \
} \
i->starget_attrs[count] = &i->private_starget_attrs[count]; \
if (i->f->show_starget_##field) \
count++
/* The FC Transport SCSI Target Attributes: */
fc_starget_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_starget_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_starget_rd_attr(port_id, "0x%06x\n", 20);
/*
* Host Attribute Management
*/
#define fc_host_show_function(field, format_string, sz, cast) \
static ssize_t \
show_fc_host_##field (struct class_device *cdev, char *buf) \
{ \
struct Scsi_Host *shost = transport_class_to_shost(cdev); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
if (i->f->get_host_##field) \
i->f->get_host_##field(shost); \
return snprintf(buf, sz, format_string, cast fc_host_##field(shost)); \
}
#define fc_host_store_function(field) \
static ssize_t \
store_fc_host_##field(struct class_device *cdev, const char *buf, \
size_t count) \
{ \
int val; \
struct Scsi_Host *shost = transport_class_to_shost(cdev); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
\
val = simple_strtoul(buf, NULL, 0); \
i->f->set_host_##field(shost, val); \
return count; \
}
#define fc_host_rd_attr(field, format_string, sz) \
fc_host_show_function(field, format_string, sz, ) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO, \
show_fc_host_##field, NULL)
#define fc_host_rd_attr_cast(field, format_string, sz, cast) \
fc_host_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO, \
show_fc_host_##field, NULL)
#define fc_host_rw_attr(field, format_string, sz) \
fc_host_show_function(field, format_string, sz, ) \
fc_host_store_function(field) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO | S_IWUSR, \
show_fc_host_##field, \
store_fc_host_##field)
#define fc_host_rd_enum_attr(title, maxlen) \
static ssize_t \
show_fc_host_##title (struct class_device *cdev, char *buf) \
{ \
struct Scsi_Host *shost = transport_class_to_shost(cdev); \
struct fc_internal *i = to_fc_internal(shost->transportt); \
const char *name; \
if (i->f->get_host_##title) \
i->f->get_host_##title(shost); \
name = get_fc_##title##_name(fc_host_##title(shost)); \
if (!name) \
return -EINVAL; \
return snprintf(buf, maxlen, "%s\n", name); \
} \
static FC_CLASS_DEVICE_ATTR(host, title, S_IRUGO, show_fc_host_##title, NULL)
#define SETUP_HOST_ATTRIBUTE_RD(field) \
i->private_host_attrs[count] = class_device_attr_host_##field; \
i->private_host_attrs[count].attr.mode = S_IRUGO; \
i->private_host_attrs[count].store = NULL; \
i->host_attrs[count] = &i->private_host_attrs[count]; \
if (i->f->show_host_##field) \
count++
#define SETUP_HOST_ATTRIBUTE_RW(field) \
i->private_host_attrs[count] = class_device_attr_host_##field; \
if (!i->f->set_host_##field) { \
i->private_host_attrs[count].attr.mode = S_IRUGO; \
i->private_host_attrs[count].store = NULL; \
} \
i->host_attrs[count] = &i->private_host_attrs[count]; \
if (i->f->show_host_##field) \
count++
#define fc_private_host_show_function(field, format_string, sz, cast) \
static ssize_t \
show_fc_host_##field (struct class_device *cdev, char *buf) \
{ \
struct Scsi_Host *shost = transport_class_to_shost(cdev); \
return snprintf(buf, sz, format_string, cast fc_host_##field(shost)); \
}
#define fc_private_host_rd_attr(field, format_string, sz) \
fc_private_host_show_function(field, format_string, sz, ) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO, \
show_fc_host_##field, NULL)
#define fc_private_host_rd_attr_cast(field, format_string, sz, cast) \
fc_private_host_show_function(field, format_string, sz, (cast)) \
static FC_CLASS_DEVICE_ATTR(host, field, S_IRUGO, \
show_fc_host_##field, NULL)
#define SETUP_PRIVATE_HOST_ATTRIBUTE_RD(field) \
i->private_host_attrs[count] = class_device_attr_host_##field; \
i->private_host_attrs[count].attr.mode = S_IRUGO; \
i->private_host_attrs[count].store = NULL; \
i->host_attrs[count] = &i->private_host_attrs[count]; \
count++
#define SETUP_PRIVATE_HOST_ATTRIBUTE_RW(field) \
{ \
i->private_host_attrs[count] = class_device_attr_host_##field; \
i->host_attrs[count] = &i->private_host_attrs[count]; \
count++; \
}
/* Fixed Host Attributes */
static ssize_t
show_fc_host_supported_classes (struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
if (fc_host_supported_classes(shost) == FC_COS_UNSPECIFIED)
return snprintf(buf, 20, "unspecified\n");
return get_fc_cos_names(fc_host_supported_classes(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, supported_classes, S_IRUGO,
show_fc_host_supported_classes, NULL);
static ssize_t
show_fc_host_supported_fc4s (struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
return (ssize_t)show_fc_fc4s(buf, fc_host_supported_fc4s(shost));
}
static FC_CLASS_DEVICE_ATTR(host, supported_fc4s, S_IRUGO,
show_fc_host_supported_fc4s, NULL);
static ssize_t
show_fc_host_supported_speeds (struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
if (fc_host_supported_speeds(shost) == FC_PORTSPEED_UNKNOWN)
return snprintf(buf, 20, "unknown\n");
return get_fc_port_speed_names(fc_host_supported_speeds(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, supported_speeds, S_IRUGO,
show_fc_host_supported_speeds, NULL);
fc_private_host_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
fc_private_host_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
fc_private_host_rd_attr_cast(permanent_port_name, "0x%llx\n", 20,
unsigned long long);
fc_private_host_rd_attr(symbolic_name, "%s\n", (FC_SYMBOLIC_NAME_SIZE +1));
fc_private_host_rd_attr(maxframe_size, "%u bytes\n", 20);
fc_private_host_rd_attr(serial_number, "%s\n", (FC_SERIAL_NUMBER_SIZE +1));
/* Dynamic Host Attributes */
static ssize_t
show_fc_host_active_fc4s (struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_internal *i = to_fc_internal(shost->transportt);
if (i->f->get_host_active_fc4s)
i->f->get_host_active_fc4s(shost);
return (ssize_t)show_fc_fc4s(buf, fc_host_active_fc4s(shost));
}
static FC_CLASS_DEVICE_ATTR(host, active_fc4s, S_IRUGO,
show_fc_host_active_fc4s, NULL);
static ssize_t
show_fc_host_speed (struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_internal *i = to_fc_internal(shost->transportt);
if (i->f->get_host_speed)
i->f->get_host_speed(shost);
if (fc_host_speed(shost) == FC_PORTSPEED_UNKNOWN)
return snprintf(buf, 20, "unknown\n");
return get_fc_port_speed_names(fc_host_speed(shost), buf);
}
static FC_CLASS_DEVICE_ATTR(host, speed, S_IRUGO,
show_fc_host_speed, NULL);
fc_host_rd_attr(port_id, "0x%06x\n", 20);
fc_host_rd_enum_attr(port_type, FC_PORTTYPE_MAX_NAMELEN);
fc_host_rd_enum_attr(port_state, FC_PORTSTATE_MAX_NAMELEN);
fc_host_rd_attr_cast(fabric_name, "0x%llx\n", 20, unsigned long long);
/* Private Host Attributes */
static ssize_t
show_fc_private_host_tgtid_bind_type(struct class_device *cdev, char *buf)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
const char *name;
name = get_fc_tgtid_bind_type_name(fc_host_tgtid_bind_type(shost));
if (!name)
return -EINVAL;
return snprintf(buf, FC_BINDTYPE_MAX_NAMELEN, "%s\n", name);
}
#define get_list_head_entry(pos, head, member) \
pos = list_entry((head)->next, typeof(*pos), member)
static ssize_t
store_fc_private_host_tgtid_bind_type(struct class_device *cdev,
const char *buf, size_t count)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_rport *rport;
enum fc_tgtid_binding_type val;
unsigned long flags;
if (get_fc_tgtid_bind_type_match(buf, &val))
return -EINVAL;
/* if changing bind type, purge all unused consistent bindings */
if (val != fc_host_tgtid_bind_type(shost)) {
spin_lock_irqsave(shost->host_lock, flags);
while (!list_empty(&fc_host_rport_bindings(shost))) {
get_list_head_entry(rport,
&fc_host_rport_bindings(shost), peers);
list_del(&rport->peers);
rport->port_state = FC_PORTSTATE_DELETED;
fc_queue_work(shost, &rport->rport_delete_work);
}
spin_unlock_irqrestore(shost->host_lock, flags);
}
fc_host_tgtid_bind_type(shost) = val;
return count;
}
static FC_CLASS_DEVICE_ATTR(host, tgtid_bind_type, S_IRUGO | S_IWUSR,
show_fc_private_host_tgtid_bind_type,
store_fc_private_host_tgtid_bind_type);
static ssize_t
store_fc_private_host_issue_lip(struct class_device *cdev,
const char *buf, size_t count)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_internal *i = to_fc_internal(shost->transportt);
int ret;
/* ignore any data value written to the attribute */
if (i->f->issue_fc_host_lip) {
ret = i->f->issue_fc_host_lip(shost);
return ret ? ret: count;
}
return -ENOENT;
}
static FC_CLASS_DEVICE_ATTR(host, issue_lip, S_IWUSR, NULL,
store_fc_private_host_issue_lip);
/*
* Host Statistics Management
*/
/* Show a given an attribute in the statistics group */
static ssize_t
fc_stat_show(const struct class_device *cdev, char *buf, unsigned long offset)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_internal *i = to_fc_internal(shost->transportt);
struct fc_host_statistics *stats;
ssize_t ret = -ENOENT;
if (offset > sizeof(struct fc_host_statistics) ||
offset % sizeof(u64) != 0)
WARN_ON(1);
if (i->f->get_fc_host_stats) {
stats = (i->f->get_fc_host_stats)(shost);
if (stats)
ret = snprintf(buf, 20, "0x%llx\n",
(unsigned long long)*(u64 *)(((u8 *) stats) + offset));
}
return ret;
}
/* generate a read-only statistics attribute */
#define fc_host_statistic(name) \
static ssize_t show_fcstat_##name(struct class_device *cd, char *buf) \
{ \
return fc_stat_show(cd, buf, \
offsetof(struct fc_host_statistics, name)); \
} \
static FC_CLASS_DEVICE_ATTR(host, name, S_IRUGO, show_fcstat_##name, NULL)
fc_host_statistic(seconds_since_last_reset);
fc_host_statistic(tx_frames);
fc_host_statistic(tx_words);
fc_host_statistic(rx_frames);
fc_host_statistic(rx_words);
fc_host_statistic(lip_count);
fc_host_statistic(nos_count);
fc_host_statistic(error_frames);
fc_host_statistic(dumped_frames);
fc_host_statistic(link_failure_count);
fc_host_statistic(loss_of_sync_count);
fc_host_statistic(loss_of_signal_count);
fc_host_statistic(prim_seq_protocol_err_count);
fc_host_statistic(invalid_tx_word_count);
fc_host_statistic(invalid_crc_count);
fc_host_statistic(fcp_input_requests);
fc_host_statistic(fcp_output_requests);
fc_host_statistic(fcp_control_requests);
fc_host_statistic(fcp_input_megabytes);
fc_host_statistic(fcp_output_megabytes);
static ssize_t
fc_reset_statistics(struct class_device *cdev, const char *buf,
size_t count)
{
struct Scsi_Host *shost = transport_class_to_shost(cdev);
struct fc_internal *i = to_fc_internal(shost->transportt);
/* ignore any data value written to the attribute */
if (i->f->reset_fc_host_stats) {
i->f->reset_fc_host_stats(shost);
return count;
}
return -ENOENT;
}
static FC_CLASS_DEVICE_ATTR(host, reset_statistics, S_IWUSR, NULL,
fc_reset_statistics);
static struct attribute *fc_statistics_attrs[] = {
&class_device_attr_host_seconds_since_last_reset.attr,
&class_device_attr_host_tx_frames.attr,
&class_device_attr_host_tx_words.attr,
&class_device_attr_host_rx_frames.attr,
&class_device_attr_host_rx_words.attr,
&class_device_attr_host_lip_count.attr,
&class_device_attr_host_nos_count.attr,
&class_device_attr_host_error_frames.attr,
&class_device_attr_host_dumped_frames.attr,
&class_device_attr_host_link_failure_count.attr,
&class_device_attr_host_loss_of_sync_count.attr,
&class_device_attr_host_loss_of_signal_count.attr,
&class_device_attr_host_prim_seq_protocol_err_count.attr,
&class_device_attr_host_invalid_tx_word_count.attr,
&class_device_attr_host_invalid_crc_count.attr,
&class_device_attr_host_fcp_input_requests.attr,
&class_device_attr_host_fcp_output_requests.attr,
&class_device_attr_host_fcp_control_requests.attr,
&class_device_attr_host_fcp_input_megabytes.attr,
&class_device_attr_host_fcp_output_megabytes.attr,
&class_device_attr_host_reset_statistics.attr,
NULL
};
static struct attribute_group fc_statistics_group = {
.name = "statistics",
.attrs = fc_statistics_attrs,
};
static int fc_host_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct fc_internal *i;
if (!scsi_is_host_device(dev))
return 0;
shost = dev_to_shost(dev);
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &fc_host_class.class)
return 0;
i = to_fc_internal(shost->transportt);
return &i->t.host_attrs.ac == cont;
}
static int fc_target_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct fc_internal *i;
if (!scsi_is_target_device(dev))
return 0;
shost = dev_to_shost(dev->parent);
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &fc_host_class.class)
return 0;
i = to_fc_internal(shost->transportt);
return &i->t.target_attrs.ac == cont;
}
static void fc_rport_dev_release(struct device *dev)
{
struct fc_rport *rport = dev_to_rport(dev);
put_device(dev->parent);
kfree(rport);
}
int scsi_is_fc_rport(const struct device *dev)
{
return dev->release == fc_rport_dev_release;
}
EXPORT_SYMBOL(scsi_is_fc_rport);
static int fc_rport_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct fc_internal *i;
if (!scsi_is_fc_rport(dev))
return 0;
shost = dev_to_shost(dev->parent);
if (!shost->transportt || shost->transportt->host_attrs.ac.class
!= &fc_host_class.class)
return 0;
i = to_fc_internal(shost->transportt);
return &i->rport_attr_cont.ac == cont;
}
/**
* fc_timed_out - FC Transport I/O timeout intercept handler
*
* @scmd: The SCSI command which timed out
*
* This routine protects against error handlers getting invoked while a
* rport is in a blocked state, typically due to a temporarily loss of
* connectivity. If the error handlers are allowed to proceed, requests
* to abort i/o, reset the target, etc will likely fail as there is no way
* to communicate with the device to perform the requested function. These
* failures may result in the midlayer taking the device offline, requiring
* manual intervention to restore operation.
*
* This routine, called whenever an i/o times out, validates the state of
* the underlying rport. If the rport is blocked, it returns
* EH_RESET_TIMER, which will continue to reschedule the timeout.
* Eventually, either the device will return, or devloss_tmo will fire,
* and when the timeout then fires, it will be handled normally.
* If the rport is not blocked, normal error handling continues.
*
* Notes:
* This routine assumes no locks are held on entry.
**/
static enum scsi_eh_timer_return
fc_timed_out(struct scsi_cmnd *scmd)
{
struct fc_rport *rport = starget_to_rport(scsi_target(scmd->device));
if (rport->port_state == FC_PORTSTATE_BLOCKED)
return EH_RESET_TIMER;
return EH_NOT_HANDLED;
}
/*
* Must be called with shost->host_lock held
*/
static int fc_user_scan(struct Scsi_Host *shost, uint channel,
uint id, uint lun)
{
struct fc_rport *rport;
list_for_each_entry(rport, &fc_host_rports(shost), peers) {
if (rport->scsi_target_id == -1)
continue;
if ((channel == SCAN_WILD_CARD || channel == rport->channel) &&
(id == SCAN_WILD_CARD || id == rport->scsi_target_id)) {
scsi_scan_target(&rport->dev, rport->channel,
rport->scsi_target_id, lun, 1);
}
}
return 0;
}
struct scsi_transport_template *
fc_attach_transport(struct fc_function_template *ft)
{
int count;
struct fc_internal *i = kzalloc(sizeof(struct fc_internal),
GFP_KERNEL);
if (unlikely(!i))
return NULL;
i->t.target_attrs.ac.attrs = &i->starget_attrs[0];
i->t.target_attrs.ac.class = &fc_transport_class.class;
i->t.target_attrs.ac.match = fc_target_match;
i->t.target_size = sizeof(struct fc_starget_attrs);
transport_container_register(&i->t.target_attrs);
i->t.host_attrs.ac.attrs = &i->host_attrs[0];
i->t.host_attrs.ac.class = &fc_host_class.class;
i->t.host_attrs.ac.match = fc_host_match;
i->t.host_size = sizeof(struct fc_host_attrs);
if (ft->get_fc_host_stats)
i->t.host_attrs.statistics = &fc_statistics_group;
transport_container_register(&i->t.host_attrs);
i->rport_attr_cont.ac.attrs = &i->rport_attrs[0];
i->rport_attr_cont.ac.class = &fc_rport_class.class;
i->rport_attr_cont.ac.match = fc_rport_match;
transport_container_register(&i->rport_attr_cont);
i->f = ft;
/* Transport uses the shost workq for scsi scanning */
i->t.create_work_queue = 1;
i->t.eh_timed_out = fc_timed_out;
i->t.user_scan = fc_user_scan;
/*
* Setup SCSI Target Attributes.
*/
count = 0;
SETUP_STARGET_ATTRIBUTE_RD(node_name);
SETUP_STARGET_ATTRIBUTE_RD(port_name);
SETUP_STARGET_ATTRIBUTE_RD(port_id);
BUG_ON(count > FC_STARGET_NUM_ATTRS);
i->starget_attrs[count] = NULL;
/*
* Setup SCSI Host Attributes.
*/
count=0;
SETUP_HOST_ATTRIBUTE_RD(node_name);
SETUP_HOST_ATTRIBUTE_RD(port_name);
SETUP_HOST_ATTRIBUTE_RD(permanent_port_name);
SETUP_HOST_ATTRIBUTE_RD(supported_classes);
SETUP_HOST_ATTRIBUTE_RD(supported_fc4s);
SETUP_HOST_ATTRIBUTE_RD(symbolic_name);
SETUP_HOST_ATTRIBUTE_RD(supported_speeds);
SETUP_HOST_ATTRIBUTE_RD(maxframe_size);
SETUP_HOST_ATTRIBUTE_RD(serial_number);
SETUP_HOST_ATTRIBUTE_RD(port_id);
SETUP_HOST_ATTRIBUTE_RD(port_type);
SETUP_HOST_ATTRIBUTE_RD(port_state);
SETUP_HOST_ATTRIBUTE_RD(active_fc4s);
SETUP_HOST_ATTRIBUTE_RD(speed);
SETUP_HOST_ATTRIBUTE_RD(fabric_name);
/* Transport-managed attributes */
SETUP_PRIVATE_HOST_ATTRIBUTE_RW(tgtid_bind_type);
if (ft->issue_fc_host_lip)
SETUP_PRIVATE_HOST_ATTRIBUTE_RW(issue_lip);
BUG_ON(count > FC_HOST_NUM_ATTRS);
i->host_attrs[count] = NULL;
/*
* Setup Remote Port Attributes.
*/
count=0;
SETUP_RPORT_ATTRIBUTE_RD(maxframe_size);
SETUP_RPORT_ATTRIBUTE_RD(supported_classes);
SETUP_RPORT_ATTRIBUTE_RW(dev_loss_tmo);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(node_name);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_name);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_id);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(roles);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(port_state);
SETUP_PRIVATE_RPORT_ATTRIBUTE_RD(scsi_target_id);
BUG_ON(count > FC_RPORT_NUM_ATTRS);
i->rport_attrs[count] = NULL;
return &i->t;
}
EXPORT_SYMBOL(fc_attach_transport);
void fc_release_transport(struct scsi_transport_template *t)
{
struct fc_internal *i = to_fc_internal(t);
transport_container_unregister(&i->t.target_attrs);
transport_container_unregister(&i->t.host_attrs);
transport_container_unregister(&i->rport_attr_cont);
kfree(i);
}
EXPORT_SYMBOL(fc_release_transport);
/**
* fc_queue_work - Queue work to the fc_host workqueue.
* @shost: Pointer to Scsi_Host bound to fc_host.
* @work: Work to queue for execution.
*
* Return value:
* 0 on success / != 0 for error
**/
static int
fc_queue_work(struct Scsi_Host *shost, struct work_struct *work)
{
if (unlikely(!fc_host_work_q(shost))) {
printk(KERN_ERR
"ERROR: FC host '%s' attempted to queue work, "
"when no workqueue created.\n", shost->hostt->name);
dump_stack();
return -EINVAL;
}
return queue_work(fc_host_work_q(shost), work);
}
/**
* fc_flush_work - Flush a fc_host's workqueue.
* @shost: Pointer to Scsi_Host bound to fc_host.
**/
static void
fc_flush_work(struct Scsi_Host *shost)
{
if (!fc_host_work_q(shost)) {
printk(KERN_ERR
"ERROR: FC host '%s' attempted to flush work, "
"when no workqueue created.\n", shost->hostt->name);
dump_stack();
return;
}
flush_workqueue(fc_host_work_q(shost));
}
/**
* fc_queue_devloss_work - Schedule work for the fc_host devloss workqueue.
* @shost: Pointer to Scsi_Host bound to fc_host.
* @work: Work to queue for execution.
* @delay: jiffies to delay the work queuing
*
* Return value:
* 0 on success / != 0 for error
**/
static int
fc_queue_devloss_work(struct Scsi_Host *shost, struct work_struct *work,
unsigned long delay)
{
if (unlikely(!fc_host_devloss_work_q(shost))) {
printk(KERN_ERR
"ERROR: FC host '%s' attempted to queue work, "
"when no workqueue created.\n", shost->hostt->name);
dump_stack();
return -EINVAL;
}
return queue_delayed_work(fc_host_devloss_work_q(shost), work, delay);
}
/**
* fc_flush_devloss - Flush a fc_host's devloss workqueue.
* @shost: Pointer to Scsi_Host bound to fc_host.
**/
static void
fc_flush_devloss(struct Scsi_Host *shost)
{
if (!fc_host_devloss_work_q(shost)) {
printk(KERN_ERR
"ERROR: FC host '%s' attempted to flush work, "
"when no workqueue created.\n", shost->hostt->name);
dump_stack();
return;
}
flush_workqueue(fc_host_devloss_work_q(shost));
}
/**
* fc_remove_host - called to terminate any fc_transport-related elements
* for a scsi host.
* @rport: remote port to be unblocked.
*
* This routine is expected to be called immediately preceeding the
* a driver's call to scsi_remove_host().
*
* WARNING: A driver utilizing the fc_transport, which fails to call
* this routine prior to scsi_remote_host(), will leave dangling
* objects in /sys/class/fc_remote_ports. Access to any of these
* objects can result in a system crash !!!
*
* Notes:
* This routine assumes no locks are held on entry.
**/
void
fc_remove_host(struct Scsi_Host *shost)
{
struct fc_rport *rport, *next_rport;
struct workqueue_struct *work_q;
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
/* Remove any remote ports */
list_for_each_entry_safe(rport, next_rport,
&fc_host->rports, peers) {
list_del(&rport->peers);
rport->port_state = FC_PORTSTATE_DELETED;
fc_queue_work(shost, &rport->rport_delete_work);
}
list_for_each_entry_safe(rport, next_rport,
&fc_host->rport_bindings, peers) {
list_del(&rport->peers);
rport->port_state = FC_PORTSTATE_DELETED;
fc_queue_work(shost, &rport->rport_delete_work);
}
/* flush all scan work items */
scsi_flush_work(shost);
/* flush all stgt delete, and rport delete work items, then kill it */
if (fc_host->work_q) {
work_q = fc_host->work_q;
fc_host->work_q = NULL;
destroy_workqueue(work_q);
}
/* flush all devloss work items, then kill it */
if (fc_host->devloss_work_q) {
work_q = fc_host->devloss_work_q;
fc_host->devloss_work_q = NULL;
destroy_workqueue(work_q);
}
}
EXPORT_SYMBOL(fc_remove_host);
/**
* fc_starget_delete - called to delete the scsi decendents of an rport
* (target and all sdevs)
*
* @data: remote port to be operated on.
**/
static void
fc_starget_delete(void *data)
{
struct fc_rport *rport = (struct fc_rport *)data;
struct Scsi_Host *shost = rport_to_shost(rport);
unsigned long flags;
scsi_target_unblock(&rport->dev);
spin_lock_irqsave(shost->host_lock, flags);
if (rport->flags & FC_RPORT_DEVLOSS_PENDING) {
spin_unlock_irqrestore(shost->host_lock, flags);
if (!cancel_delayed_work(&rport->dev_loss_work))
fc_flush_devloss(shost);
spin_lock_irqsave(shost->host_lock, flags);
rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
}
spin_unlock_irqrestore(shost->host_lock, flags);
scsi_remove_target(&rport->dev);
}
/**
* fc_rport_final_delete - finish rport termination and delete it.
*
* @data: remote port to be deleted.
**/
static void
fc_rport_final_delete(void *data)
{
struct fc_rport *rport = (struct fc_rport *)data;
struct device *dev = &rport->dev;
struct Scsi_Host *shost = rport_to_shost(rport);
/* Delete SCSI target and sdevs */
if (rport->scsi_target_id != -1)
fc_starget_delete(data);
/*
* if a scan is pending, flush the SCSI Host work_q so that
* that we can reclaim the rport scan work element.
*/
if (rport->flags & FC_RPORT_SCAN_PENDING)
scsi_flush_work(shost);
transport_remove_device(dev);
device_del(dev);
transport_destroy_device(dev);
put_device(&shost->shost_gendev);
}
/**
* fc_rport_create - allocates and creates a remote FC port.
* @shost: scsi host the remote port is connected to.
* @channel: Channel on shost port connected to.
* @ids: The world wide names, fc address, and FC4 port
* roles for the remote port.
*
* Allocates and creates the remoter port structure, including the
* class and sysfs creation.
*
* Notes:
* This routine assumes no locks are held on entry.
**/
struct fc_rport *
fc_rport_create(struct Scsi_Host *shost, int channel,
struct fc_rport_identifiers *ids)
{
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
struct fc_internal *fci = to_fc_internal(shost->transportt);
struct fc_rport *rport;
struct device *dev;
unsigned long flags;
int error;
size_t size;
size = (sizeof(struct fc_rport) + fci->f->dd_fcrport_size);
rport = kzalloc(size, GFP_KERNEL);
if (unlikely(!rport)) {
printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__);
return NULL;
}
rport->maxframe_size = -1;
rport->supported_classes = FC_COS_UNSPECIFIED;
rport->dev_loss_tmo = fc_dev_loss_tmo;
memcpy(&rport->node_name, &ids->node_name, sizeof(rport->node_name));
memcpy(&rport->port_name, &ids->port_name, sizeof(rport->port_name));
rport->port_id = ids->port_id;
rport->roles = ids->roles;
rport->port_state = FC_PORTSTATE_ONLINE;
if (fci->f->dd_fcrport_size)
rport->dd_data = &rport[1];
rport->channel = channel;
INIT_WORK(&rport->dev_loss_work, fc_timeout_deleted_rport, rport);
INIT_WORK(&rport->scan_work, fc_scsi_scan_rport, rport);
INIT_WORK(&rport->stgt_delete_work, fc_starget_delete, rport);
INIT_WORK(&rport->rport_delete_work, fc_rport_final_delete, rport);
spin_lock_irqsave(shost->host_lock, flags);
rport->number = fc_host->next_rport_number++;
if (rport->roles & FC_RPORT_ROLE_FCP_TARGET)
rport->scsi_target_id = fc_host->next_target_id++;
else
rport->scsi_target_id = -1;
list_add_tail(&rport->peers, &fc_host->rports);
get_device(&shost->shost_gendev);
spin_unlock_irqrestore(shost->host_lock, flags);
dev = &rport->dev;
device_initialize(dev);
dev->parent = get_device(&shost->shost_gendev);
dev->release = fc_rport_dev_release;
sprintf(dev->bus_id, "rport-%d:%d-%d",
shost->host_no, channel, rport->number);
transport_setup_device(dev);
error = device_add(dev);
if (error) {
printk(KERN_ERR "FC Remote Port device_add failed\n");
goto delete_rport;
}
transport_add_device(dev);
transport_configure_device(dev);
if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) {
/* initiate a scan of the target */
rport->flags |= FC_RPORT_SCAN_PENDING;
scsi_queue_work(shost, &rport->scan_work);
}
return rport;
delete_rport:
transport_destroy_device(dev);
put_device(dev->parent);
spin_lock_irqsave(shost->host_lock, flags);
list_del(&rport->peers);
put_device(&shost->shost_gendev);
spin_unlock_irqrestore(shost->host_lock, flags);
put_device(dev->parent);
kfree(rport);
return NULL;
}
/**
* fc_remote_port_add - notifies the fc transport of the existence
* of a remote FC port.
* @shost: scsi host the remote port is connected to.
* @channel: Channel on shost port connected to.
* @ids: The world wide names, fc address, and FC4 port
* roles for the remote port.
*
* The LLDD calls this routine to notify the transport of the existence
* of a remote port. The LLDD provides the unique identifiers (wwpn,wwn)
* of the port, it's FC address (port_id), and the FC4 roles that are
* active for the port.
*
* For ports that are FCP targets (aka scsi targets), the FC transport
* maintains consistent target id bindings on behalf of the LLDD.
* A consistent target id binding is an assignment of a target id to
* a remote port identifier, which persists while the scsi host is
* attached. The remote port can disappear, then later reappear, and
* it's target id assignment remains the same. This allows for shifts
* in FC addressing (if binding by wwpn or wwnn) with no apparent
* changes to the scsi subsystem which is based on scsi host number and
* target id values. Bindings are only valid during the attachment of
* the scsi host. If the host detaches, then later re-attaches, target
* id bindings may change.
*
* This routine is responsible for returning a remote port structure.
* The routine will search the list of remote ports it maintains
* internally on behalf of consistent target id mappings. If found, the
* remote port structure will be reused. Otherwise, a new remote port
* structure will be allocated.
*
* Whenever a remote port is allocated, a new fc_remote_port class
* device is created.
*
* Should not be called from interrupt context.
*
* Notes:
* This routine assumes no locks are held on entry.
**/
struct fc_rport *
fc_remote_port_add(struct Scsi_Host *shost, int channel,
struct fc_rport_identifiers *ids)
{
struct fc_internal *fci = to_fc_internal(shost->transportt);
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
struct fc_rport *rport;
unsigned long flags;
int match = 0;
/* ensure any stgt delete functions are done */
fc_flush_work(shost);
/*
* Search the list of "active" rports, for an rport that has been
* deleted, but we've held off the real delete while the target
* is in a "blocked" state.
*/
spin_lock_irqsave(shost->host_lock, flags);
list_for_each_entry(rport, &fc_host->rports, peers) {
if ((rport->port_state == FC_PORTSTATE_BLOCKED) &&
(rport->channel == channel)) {
switch (fc_host->tgtid_bind_type) {
case FC_TGTID_BIND_BY_WWPN:
case FC_TGTID_BIND_NONE:
if (rport->port_name == ids->port_name)
match = 1;
break;
case FC_TGTID_BIND_BY_WWNN:
if (rport->node_name == ids->node_name)
match = 1;
break;
case FC_TGTID_BIND_BY_ID:
if (rport->port_id == ids->port_id)
match = 1;
break;
}
if (match) {
struct work_struct *work =
&rport->dev_loss_work;
memcpy(&rport->node_name, &ids->node_name,
sizeof(rport->node_name));
memcpy(&rport->port_name, &ids->port_name,
sizeof(rport->port_name));
rport->port_id = ids->port_id;
rport->port_state = FC_PORTSTATE_ONLINE;
rport->roles = ids->roles;
spin_unlock_irqrestore(shost->host_lock, flags);
if (fci->f->dd_fcrport_size)
memset(rport->dd_data, 0,
fci->f->dd_fcrport_size);
/*
* If we were blocked, we were a target.
* If no longer a target, we leave the timer
* running in case the port changes roles
* prior to the timer expiring. If the timer
* fires, the target will be torn down.
*/
if (!(ids->roles & FC_RPORT_ROLE_FCP_TARGET))
return rport;
/* restart the target */
/*
* Stop the target timer first. Take no action
* on the del_timer failure as the state
* machine state change will validate the
* transaction.
*/
if (!cancel_delayed_work(work))
fc_flush_devloss(shost);
spin_lock_irqsave(shost->host_lock, flags);
rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
/* initiate a scan of the target */
rport->flags |= FC_RPORT_SCAN_PENDING;
scsi_queue_work(shost, &rport->scan_work);
spin_unlock_irqrestore(shost->host_lock, flags);
return rport;
}
}
}
/* Search the bindings array */
if (fc_host->tgtid_bind_type != FC_TGTID_BIND_NONE) {
/* search for a matching consistent binding */
list_for_each_entry(rport, &fc_host->rport_bindings,
peers) {
if (rport->channel != channel)
continue;
switch (fc_host->tgtid_bind_type) {
case FC_TGTID_BIND_BY_WWPN:
if (rport->port_name == ids->port_name)
match = 1;
break;
case FC_TGTID_BIND_BY_WWNN:
if (rport->node_name == ids->node_name)
match = 1;
break;
case FC_TGTID_BIND_BY_ID:
if (rport->port_id == ids->port_id)
match = 1;
break;
case FC_TGTID_BIND_NONE: /* to keep compiler happy */
break;
}
if (match) {
list_move_tail(&rport->peers, &fc_host->rports);
break;
}
}
if (match) {
memcpy(&rport->node_name, &ids->node_name,
sizeof(rport->node_name));
memcpy(&rport->port_name, &ids->port_name,
sizeof(rport->port_name));
rport->port_id = ids->port_id;
rport->roles = ids->roles;
rport->port_state = FC_PORTSTATE_ONLINE;
if (fci->f->dd_fcrport_size)
memset(rport->dd_data, 0,
fci->f->dd_fcrport_size);
if (rport->roles & FC_RPORT_ROLE_FCP_TARGET) {
/* initiate a scan of the target */
rport->flags |= FC_RPORT_SCAN_PENDING;
scsi_queue_work(shost, &rport->scan_work);
}
spin_unlock_irqrestore(shost->host_lock, flags);
return rport;
}
}
spin_unlock_irqrestore(shost->host_lock, flags);
/* No consistent binding found - create new remote port entry */
rport = fc_rport_create(shost, channel, ids);
return rport;
}
EXPORT_SYMBOL(fc_remote_port_add);
/**
* fc_remote_port_delete - notifies the fc transport that a remote
* port is no longer in existence.
* @rport: The remote port that no longer exists
*
* The LLDD calls this routine to notify the transport that a remote
* port is no longer part of the topology. Note: Although a port
* may no longer be part of the topology, it may persist in the remote
* ports displayed by the fc_host. We do this under 2 conditions:
* - If the port was a scsi target, we delay its deletion by "blocking" it.
* This allows the port to temporarily disappear, then reappear without
* disrupting the SCSI device tree attached to it. During the "blocked"
* period the port will still exist.
* - If the port was a scsi target and disappears for longer than we
* expect, we'll delete the port and the tear down the SCSI device tree
* attached to it. However, we want to semi-persist the target id assigned
* to that port if it eventually does exist. The port structure will
* remain (although with minimal information) so that the target id
* bindings remails.
*
* If the remote port is not an FCP Target, it will be fully torn down
* and deallocated, including the fc_remote_port class device.
*
* If the remote port is an FCP Target, the port will be placed in a
* temporary blocked state. From the LLDD's perspective, the rport no
* longer exists. From the SCSI midlayer's perspective, the SCSI target
* exists, but all sdevs on it are blocked from further I/O. The following
* is then expected:
* If the remote port does not return (signaled by a LLDD call to
* fc_remote_port_add()) within the dev_loss_tmo timeout, then the
* scsi target is removed - killing all outstanding i/o and removing the
* scsi devices attached ot it. The port structure will be marked Not
* Present and be partially cleared, leaving only enough information to
* recognize the remote port relative to the scsi target id binding if
* it later appears. The port will remain as long as there is a valid
* binding (e.g. until the user changes the binding type or unloads the
* scsi host with the binding).
*
* If the remote port returns within the dev_loss_tmo value (and matches
* according to the target id binding type), the port structure will be
* reused. If it is no longer a SCSI target, the target will be torn
* down. If it continues to be a SCSI target, then the target will be
* unblocked (allowing i/o to be resumed), and a scan will be activated
* to ensure that all luns are detected.
*
* Called from normal process context only - cannot be called from interrupt.
*
* Notes:
* This routine assumes no locks are held on entry.
**/
void
fc_remote_port_delete(struct fc_rport *rport)
{
struct Scsi_Host *shost = rport_to_shost(rport);
int timeout = rport->dev_loss_tmo;
unsigned long flags;
/*
* No need to flush the fc_host work_q's, as all adds are synchronous.
*
* We do need to reclaim the rport scan work element, so eventually
* (in fc_rport_final_delete()) we'll flush the scsi host work_q if
* there's still a scan pending.
*/
spin_lock_irqsave(shost->host_lock, flags);
/* If no scsi target id mapping, delete it */
if (rport->scsi_target_id == -1) {
list_del(&rport->peers);
rport->port_state = FC_PORTSTATE_DELETED;
fc_queue_work(shost, &rport->rport_delete_work);
spin_unlock_irqrestore(shost->host_lock, flags);
return;
}
rport->port_state = FC_PORTSTATE_BLOCKED;
rport->flags |= FC_RPORT_DEVLOSS_PENDING;
spin_unlock_irqrestore(shost->host_lock, flags);
scsi_target_block(&rport->dev);
/* cap the length the devices can be blocked until they are deleted */
fc_queue_devloss_work(shost, &rport->dev_loss_work, timeout * HZ);
}
EXPORT_SYMBOL(fc_remote_port_delete);
/**
* fc_remote_port_rolechg - notifies the fc transport that the roles
* on a remote may have changed.
* @rport: The remote port that changed.
*
* The LLDD calls this routine to notify the transport that the roles
* on a remote port may have changed. The largest effect of this is
* if a port now becomes a FCP Target, it must be allocated a
* scsi target id. If the port is no longer a FCP target, any
* scsi target id value assigned to it will persist in case the
* role changes back to include FCP Target. No changes in the scsi
* midlayer will be invoked if the role changes (in the expectation
* that the role will be resumed. If it doesn't normal error processing
* will take place).
*
* Should not be called from interrupt context.
*
* Notes:
* This routine assumes no locks are held on entry.
**/
void
fc_remote_port_rolechg(struct fc_rport *rport, u32 roles)
{
struct Scsi_Host *shost = rport_to_shost(rport);
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
unsigned long flags;
int create = 0;
spin_lock_irqsave(shost->host_lock, flags);
if (roles & FC_RPORT_ROLE_FCP_TARGET) {
if (rport->scsi_target_id == -1) {
rport->scsi_target_id = fc_host->next_target_id++;
create = 1;
} else if (!(rport->roles & FC_RPORT_ROLE_FCP_TARGET))
create = 1;
}
rport->roles = roles;
spin_unlock_irqrestore(shost->host_lock, flags);
if (create) {
/*
* There may have been a delete timer running on the
* port. Ensure that it is cancelled as we now know
* the port is an FCP Target.
* Note: we know the rport is exists and in an online
* state as the LLDD would not have had an rport
* reference to pass us.
*
* Take no action on the del_timer failure as the state
* machine state change will validate the
* transaction.
*/
if (!cancel_delayed_work(&rport->dev_loss_work))
fc_flush_devloss(shost);
spin_lock_irqsave(shost->host_lock, flags);
rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
spin_unlock_irqrestore(shost->host_lock, flags);
/* ensure any stgt delete functions are done */
fc_flush_work(shost);
/* initiate a scan of the target */
spin_lock_irqsave(shost->host_lock, flags);
rport->flags |= FC_RPORT_SCAN_PENDING;
scsi_queue_work(shost, &rport->scan_work);
spin_unlock_irqrestore(shost->host_lock, flags);
}
}
EXPORT_SYMBOL(fc_remote_port_rolechg);
/**
* fc_timeout_deleted_rport - Timeout handler for a deleted remote port that
* was a SCSI target (thus was blocked), and failed
* to return in the alloted time.
*
* @data: rport target that failed to reappear in the alloted time.
**/
static void
fc_timeout_deleted_rport(void *data)
{
struct fc_rport *rport = (struct fc_rport *)data;
struct Scsi_Host *shost = rport_to_shost(rport);
struct fc_host_attrs *fc_host = shost_to_fc_host(shost);
unsigned long flags;
spin_lock_irqsave(shost->host_lock, flags);
rport->flags &= ~FC_RPORT_DEVLOSS_PENDING;
/*
* If the port is ONLINE, then it came back. Validate it's still an
* FCP target. If not, tear down the scsi_target on it.
*/
if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
!(rport->roles & FC_RPORT_ROLE_FCP_TARGET)) {
dev_printk(KERN_ERR, &rport->dev,
"blocked FC remote port time out: no longer"
" a FCP target, removing starget\n");
fc_queue_work(shost, &rport->stgt_delete_work);
spin_unlock_irqrestore(shost->host_lock, flags);
return;
}
if (rport->port_state != FC_PORTSTATE_BLOCKED) {
spin_unlock_irqrestore(shost->host_lock, flags);
dev_printk(KERN_ERR, &rport->dev,
"blocked FC remote port time out: leaving target alone\n");
return;
}
if (fc_host->tgtid_bind_type == FC_TGTID_BIND_NONE) {
list_del(&rport->peers);
rport->port_state = FC_PORTSTATE_DELETED;
dev_printk(KERN_ERR, &rport->dev,
"blocked FC remote port time out: removing target\n");
fc_queue_work(shost, &rport->rport_delete_work);
spin_unlock_irqrestore(shost->host_lock, flags);
return;
}
dev_printk(KERN_ERR, &rport->dev,
"blocked FC remote port time out: removing target and "
"saving binding\n");
list_move_tail(&rport->peers, &fc_host->rport_bindings);
/*
* Note: We do not remove or clear the hostdata area. This allows
* host-specific target data to persist along with the
* scsi_target_id. It's up to the host to manage it's hostdata area.
*/
/*
* Reinitialize port attributes that may change if the port comes back.
*/
rport->maxframe_size = -1;
rport->supported_classes = FC_COS_UNSPECIFIED;
rport->roles = FC_RPORT_ROLE_UNKNOWN;
rport->port_state = FC_PORTSTATE_NOTPRESENT;
/* remove the identifiers that aren't used in the consisting binding */
switch (fc_host->tgtid_bind_type) {
case FC_TGTID_BIND_BY_WWPN:
rport->node_name = -1;
rport->port_id = -1;
break;
case FC_TGTID_BIND_BY_WWNN:
rport->port_name = -1;
rport->port_id = -1;
break;
case FC_TGTID_BIND_BY_ID:
rport->node_name = -1;
rport->port_name = -1;
break;
case FC_TGTID_BIND_NONE: /* to keep compiler happy */
break;
}
/*
* As this only occurs if the remote port (scsi target)
* went away and didn't come back - we'll remove
* all attached scsi devices.
*/
fc_queue_work(shost, &rport->stgt_delete_work);
spin_unlock_irqrestore(shost->host_lock, flags);
}
/**
* fc_scsi_scan_rport - called to perform a scsi scan on a remote port.
*
* Will unblock the target (in case it went away and has now come back),
* then invoke a scan.
*
* @data: remote port to be scanned.
**/
static void
fc_scsi_scan_rport(void *data)
{
struct fc_rport *rport = (struct fc_rport *)data;
struct Scsi_Host *shost = rport_to_shost(rport);
unsigned long flags;
if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
(rport->roles & FC_RPORT_ROLE_FCP_TARGET)) {
scsi_target_unblock(&rport->dev);
scsi_scan_target(&rport->dev, rport->channel,
rport->scsi_target_id, SCAN_WILD_CARD, 1);
}
spin_lock_irqsave(shost->host_lock, flags);
rport->flags &= ~FC_RPORT_SCAN_PENDING;
spin_unlock_irqrestore(shost->host_lock, flags);
}
MODULE_AUTHOR("Martin Hicks");
MODULE_DESCRIPTION("FC Transport Attributes");
MODULE_LICENSE("GPL");
module_init(fc_transport_init);
module_exit(fc_transport_exit);