/*
* zfcp device driver
*
* Module interface and handling of zfcp data structures.
*
* Copyright IBM Corporation 2002, 2009
*/
/*
* Driver authors:
* Martin Peschke (originator of the driver)
* Raimund Schroeder
* Aron Zeh
* Wolfgang Taphorn
* Stefan Bader
* Heiko Carstens (kernel 2.6 port of the driver)
* Andreas Herrmann
* Maxim Shchetynin
* Volker Sameske
* Ralph Wuerthner
* Michael Loehr
* Swen Schillig
* Christof Schmitt
* Martin Petermann
* Sven Schuetz
*/
#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/miscdevice.h>
#include <linux/seq_file.h>
#include "zfcp_ext.h"
#define ZFCP_BUS_ID_SIZE 20
MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
MODULE_DESCRIPTION("FCP HBA driver");
MODULE_LICENSE("GPL");
static char *init_device;
module_param_named(device, init_device, charp, 0400);
MODULE_PARM_DESC(device, "specify initial device");
static struct kmem_cache *zfcp_cache_hw_align(const char *name,
unsigned long size)
{
return kmem_cache_create(name, size, roundup_pow_of_two(size), 0, NULL);
}
static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
{
int idx;
adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
GFP_KERNEL);
if (!adapter->req_list)
return -ENOMEM;
for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
INIT_LIST_HEAD(&adapter->req_list[idx]);
return 0;
}
/**
* zfcp_reqlist_isempty - is the request list empty
* @adapter: pointer to struct zfcp_adapter
*
* Returns: true if list is empty, false otherwise
*/
int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
{
unsigned int idx;
for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
if (!list_empty(&adapter->req_list[idx]))
return 0;
return 1;
}
static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
{
struct ccw_device *ccwdev;
struct zfcp_adapter *adapter;
struct zfcp_port *port;
struct zfcp_unit *unit;
ccwdev = get_ccwdev_by_busid(&zfcp_ccw_driver, busid);
if (!ccwdev)
return;
if (ccw_device_set_online(ccwdev))
goto out_ccwdev;
mutex_lock(&zfcp_data.config_mutex);
adapter = dev_get_drvdata(&ccwdev->dev);
if (!adapter)
goto out_unlock;
zfcp_adapter_get(adapter);
port = zfcp_get_port_by_wwpn(adapter, wwpn);
if (!port)
goto out_port;
zfcp_port_get(port);
unit = zfcp_unit_enqueue(port, lun);
if (IS_ERR(unit))
goto out_unit;
mutex_unlock(&zfcp_data.config_mutex);
zfcp_erp_unit_reopen(unit, 0, "auidc_1", NULL);
zfcp_erp_wait(adapter);
flush_work(&unit->scsi_work);
mutex_lock(&zfcp_data.config_mutex);
zfcp_unit_put(unit);
out_unit:
zfcp_port_put(port);
out_port:
zfcp_adapter_put(adapter);
out_unlock:
mutex_unlock(&zfcp_data.config_mutex);
out_ccwdev:
put_device(&ccwdev->dev);
return;
}
static void __init zfcp_init_device_setup(char *devstr)
{
char *token;
char *str;
char busid[ZFCP_BUS_ID_SIZE];
u64 wwpn, lun;
/* duplicate devstr and keep the original for sysfs presentation*/
str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
if (!str)
return;
strcpy(str, devstr);
token = strsep(&str, ",");
if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
goto err_out;
strncpy(busid, token, ZFCP_BUS_ID_SIZE);
token = strsep(&str, ",");
if (!token || strict_strtoull(token, 0, (unsigned long long *) &wwpn))
goto err_out;
token = strsep(&str, ",");
if (!token || strict_strtoull(token, 0, (unsigned long long *) &lun))
goto err_out;
kfree(str);
zfcp_init_device_configure(busid, wwpn, lun);
return;
err_out:
kfree(str);
pr_err("%s is not a valid SCSI device\n", devstr);
}
static int __init zfcp_module_init(void)
{
int retval = -ENOMEM;
zfcp_data.gpn_ft_cache = zfcp_cache_hw_align("zfcp_gpn",
sizeof(struct ct_iu_gpn_ft_req));
if (!zfcp_data.gpn_ft_cache)
goto out;
zfcp_data.qtcb_cache = zfcp_cache_hw_align("zfcp_qtcb",
sizeof(struct fsf_qtcb));
if (!zfcp_data.qtcb_cache)
goto out_qtcb_cache;
zfcp_data.sr_buffer_cache = zfcp_cache_hw_align("zfcp_sr",
sizeof(struct fsf_status_read_buffer));
if (!zfcp_data.sr_buffer_cache)
goto out_sr_cache;
zfcp_data.gid_pn_cache = zfcp_cache_hw_align("zfcp_gid",
sizeof(struct zfcp_gid_pn_data));
if (!zfcp_data.gid_pn_cache)
goto out_gid_cache;
mutex_init(&zfcp_data.config_mutex);
rwlock_init(&zfcp_data.config_lock);
zfcp_data.scsi_transport_template =
fc_attach_transport(&zfcp_transport_functions);
if (!zfcp_data.scsi_transport_template)
goto out_transport;
retval = misc_register(&zfcp_cfdc_misc);
if (retval) {
pr_err("Registering the misc device zfcp_cfdc failed\n");
goto out_misc;
}
retval = zfcp_ccw_register();
if (retval) {
pr_err("The zfcp device driver could not register with "
"the common I/O layer\n");
goto out_ccw_register;
}
if (init_device)
zfcp_init_device_setup(init_device);
return 0;
out_ccw_register:
misc_deregister(&zfcp_cfdc_misc);
out_misc:
fc_release_transport(zfcp_data.scsi_transport_template);
out_transport:
kmem_cache_destroy(zfcp_data.gid_pn_cache);
out_gid_cache:
kmem_cache_destroy(zfcp_data.sr_buffer_cache);
out_sr_cache:
kmem_cache_destroy(zfcp_data.qtcb_cache);
out_qtcb_cache:
kmem_cache_destroy(zfcp_data.gpn_ft_cache);
out:
return retval;
}
module_init(zfcp_module_init);
/**
* zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
* @port: pointer to port to search for unit
* @fcp_lun: FCP LUN to search for
*
* Returns: pointer to zfcp_unit or NULL
*/
struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
{
struct zfcp_unit *unit;
list_for_each_entry(unit, &port->unit_list_head, list)
if ((unit->fcp_lun == fcp_lun) &&
!(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
return unit;
return NULL;
}
/**
* zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
* @adapter: pointer to adapter to search for port
* @wwpn: wwpn to search for
*
* Returns: pointer to zfcp_port or NULL
*/
struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
u64 wwpn)
{
struct zfcp_port *port;
list_for_each_entry(port, &adapter->port_list_head, list)
if ((port->wwpn == wwpn) &&
!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_REMOVE))
return port;
return NULL;
}
static void zfcp_sysfs_unit_release(struct device *dev)
{
kfree(container_of(dev, struct zfcp_unit, sysfs_device));
}
/**
* zfcp_unit_enqueue - enqueue unit to unit list of a port.
* @port: pointer to port where unit is added
* @fcp_lun: FCP LUN of unit to be enqueued
* Returns: pointer to enqueued unit on success, ERR_PTR on error
* Locks: config_mutex must be held to serialize changes to the unit list
*
* Sets up some unit internal structures and creates sysfs entry.
*/
struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
{
struct zfcp_unit *unit;
read_lock_irq(&zfcp_data.config_lock);
if (zfcp_get_unit_by_lun(port, fcp_lun)) {
read_unlock_irq(&zfcp_data.config_lock);
return ERR_PTR(-EINVAL);
}
read_unlock_irq(&zfcp_data.config_lock);
unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
if (!unit)
return ERR_PTR(-ENOMEM);
atomic_set(&unit->refcount, 0);
init_waitqueue_head(&unit->remove_wq);
INIT_WORK(&unit->scsi_work, zfcp_scsi_scan);
unit->port = port;
unit->fcp_lun = fcp_lun;
if (dev_set_name(&unit->sysfs_device, "0x%016llx",
(unsigned long long) fcp_lun)) {
kfree(unit);
return ERR_PTR(-ENOMEM);
}
unit->sysfs_device.parent = &port->sysfs_device;
unit->sysfs_device.release = zfcp_sysfs_unit_release;
dev_set_drvdata(&unit->sysfs_device, unit);
/* mark unit unusable as long as sysfs registration is not complete */
atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
spin_lock_init(&unit->latencies.lock);
unit->latencies.write.channel.min = 0xFFFFFFFF;
unit->latencies.write.fabric.min = 0xFFFFFFFF;
unit->latencies.read.channel.min = 0xFFFFFFFF;
unit->latencies.read.fabric.min = 0xFFFFFFFF;
unit->latencies.cmd.channel.min = 0xFFFFFFFF;
unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
if (device_register(&unit->sysfs_device)) {
put_device(&unit->sysfs_device);
return ERR_PTR(-EINVAL);
}
if (sysfs_create_group(&unit->sysfs_device.kobj,
&zfcp_sysfs_unit_attrs)) {
device_unregister(&unit->sysfs_device);
return ERR_PTR(-EINVAL);
}
zfcp_unit_get(unit);
write_lock_irq(&zfcp_data.config_lock);
list_add_tail(&unit->list, &port->unit_list_head);
atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
write_unlock_irq(&zfcp_data.config_lock);
zfcp_port_get(port);
return unit;
}
/**
* zfcp_unit_dequeue - dequeue unit
* @unit: pointer to zfcp_unit
*
* waits until all work is done on unit and removes it then from the unit->list
* of the associated port.
*/
void zfcp_unit_dequeue(struct zfcp_unit *unit)
{
wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
write_lock_irq(&zfcp_data.config_lock);
list_del(&unit->list);
write_unlock_irq(&zfcp_data.config_lock);
zfcp_port_put(unit->port);
sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
device_unregister(&unit->sysfs_device);
}
static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
{
/* must only be called with zfcp_data.config_mutex taken */
adapter->pool.erp_req =
mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
if (!adapter->pool.erp_req)
return -ENOMEM;
adapter->pool.gid_pn_req =
mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
if (!adapter->pool.gid_pn_req)
return -ENOMEM;
adapter->pool.scsi_req =
mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
if (!adapter->pool.scsi_req)
return -ENOMEM;
adapter->pool.scsi_abort =
mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
if (!adapter->pool.scsi_abort)
return -ENOMEM;
adapter->pool.status_read_req =
mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
sizeof(struct zfcp_fsf_req));
if (!adapter->pool.status_read_req)
return -ENOMEM;
adapter->pool.qtcb_pool =
mempool_create_slab_pool(4, zfcp_data.qtcb_cache);
if (!adapter->pool.qtcb_pool)
return -ENOMEM;
adapter->pool.status_read_data =
mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
zfcp_data.sr_buffer_cache);
if (!adapter->pool.status_read_data)
return -ENOMEM;
adapter->pool.gid_pn_data =
mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
if (!adapter->pool.gid_pn_data)
return -ENOMEM;
return 0;
}
static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
{
/* zfcp_data.config_mutex must be held */
if (adapter->pool.erp_req)
mempool_destroy(adapter->pool.erp_req);
if (adapter->pool.scsi_req)
mempool_destroy(adapter->pool.scsi_req);
if (adapter->pool.scsi_abort)
mempool_destroy(adapter->pool.scsi_abort);
if (adapter->pool.qtcb_pool)
mempool_destroy(adapter->pool.qtcb_pool);
if (adapter->pool.status_read_req)
mempool_destroy(adapter->pool.status_read_req);
if (adapter->pool.status_read_data)
mempool_destroy(adapter->pool.status_read_data);
if (adapter->pool.gid_pn_data)
mempool_destroy(adapter->pool.gid_pn_data);
}
/**
* zfcp_status_read_refill - refill the long running status_read_requests
* @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
*
* Returns: 0 on success, 1 otherwise
*
* if there are 16 or more status_read requests missing an adapter_reopen
* is triggered
*/
int zfcp_status_read_refill(struct zfcp_adapter *adapter)
{
while (atomic_read(&adapter->stat_miss) > 0)
if (zfcp_fsf_status_read(adapter->qdio)) {
if (atomic_read(&adapter->stat_miss) >= 16) {
zfcp_erp_adapter_reopen(adapter, 0, "axsref1",
NULL);
return 1;
}
break;
} else
atomic_dec(&adapter->stat_miss);
return 0;
}
static void _zfcp_status_read_scheduler(struct work_struct *work)
{
zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
stat_work));
}
static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
{
struct zfcp_adapter *adapter =
container_of(sl, struct zfcp_adapter, service_level);
seq_printf(m, "zfcp: %s microcode level %x\n",
dev_name(&adapter->ccw_device->dev),
adapter->fsf_lic_version);
}
static int zfcp_setup_adapter_work_queue(struct zfcp_adapter *adapter)
{
char name[TASK_COMM_LEN];
snprintf(name, sizeof(name), "zfcp_q_%s",
dev_name(&adapter->ccw_device->dev));
adapter->work_queue = create_singlethread_workqueue(name);
if (adapter->work_queue)
return 0;
return -ENOMEM;
}
static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter)
{
if (adapter->work_queue)
destroy_workqueue(adapter->work_queue);
adapter->work_queue = NULL;
}
/**
* zfcp_adapter_enqueue - enqueue a new adapter to the list
* @ccw_device: pointer to the struct cc_device
*
* Returns: 0 if a new adapter was successfully enqueued
* -ENOMEM if alloc failed
* Enqueues an adapter at the end of the adapter list in the driver data.
* All adapter internal structures are set up.
* Proc-fs entries are also created.
* locks: config_mutex must be held to serialize changes to the adapter list
*/
int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
{
struct zfcp_adapter *adapter;
/*
* Note: It is safe to release the list_lock, as any list changes
* are protected by the config_mutex, which must be held to get here
*/
adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
if (!adapter)
return -ENOMEM;
ccw_device->handler = NULL;
adapter->ccw_device = ccw_device;
atomic_set(&adapter->refcount, 0);
if (zfcp_qdio_setup(adapter))
goto qdio_failed;
if (zfcp_allocate_low_mem_buffers(adapter))
goto low_mem_buffers_failed;
if (zfcp_reqlist_alloc(adapter))
goto low_mem_buffers_failed;
if (zfcp_dbf_adapter_register(adapter))
goto debug_register_failed;
if (zfcp_setup_adapter_work_queue(adapter))
goto work_queue_failed;
if (zfcp_fc_gs_setup(adapter))
goto generic_services_failed;
init_waitqueue_head(&adapter->remove_wq);
init_waitqueue_head(&adapter->erp_ready_wq);
init_waitqueue_head(&adapter->erp_done_wqh);
INIT_LIST_HEAD(&adapter->port_list_head);
INIT_LIST_HEAD(&adapter->erp_ready_head);
INIT_LIST_HEAD(&adapter->erp_running_head);
spin_lock_init(&adapter->req_list_lock);
rwlock_init(&adapter->erp_lock);
rwlock_init(&adapter->abort_lock);
if (zfcp_erp_thread_setup(adapter))
goto erp_thread_failed;
INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
INIT_WORK(&adapter->scan_work, _zfcp_fc_scan_ports_later);
adapter->service_level.seq_print = zfcp_print_sl;
/* mark adapter unusable as long as sysfs registration is not complete */
atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
dev_set_drvdata(&ccw_device->dev, adapter);
if (sysfs_create_group(&ccw_device->dev.kobj,
&zfcp_sysfs_adapter_attrs))
goto sysfs_failed;
atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
if (!zfcp_adapter_scsi_register(adapter))
return 0;
sysfs_failed:
zfcp_erp_thread_kill(adapter);
erp_thread_failed:
zfcp_fc_gs_destroy(adapter);
generic_services_failed:
zfcp_destroy_adapter_work_queue(adapter);
work_queue_failed:
zfcp_dbf_adapter_unregister(adapter->dbf);
debug_register_failed:
dev_set_drvdata(&ccw_device->dev, NULL);
kfree(adapter->req_list);
low_mem_buffers_failed:
zfcp_free_low_mem_buffers(adapter);
qdio_failed:
zfcp_qdio_destroy(adapter->qdio);
kfree(adapter);
return -ENOMEM;
}
/**
* zfcp_adapter_dequeue - remove the adapter from the resource list
* @adapter: pointer to struct zfcp_adapter which should be removed
* locks: adapter list write lock is assumed to be held by caller
*/
void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
{
int retval = 0;
unsigned long flags;
cancel_work_sync(&adapter->stat_work);
zfcp_fc_wka_ports_force_offline(adapter->gs);
sysfs_remove_group(&adapter->ccw_device->dev.kobj,
&zfcp_sysfs_adapter_attrs);
dev_set_drvdata(&adapter->ccw_device->dev, NULL);
/* sanity check: no pending FSF requests */
spin_lock_irqsave(&adapter->req_list_lock, flags);
retval = zfcp_reqlist_isempty(adapter);
spin_unlock_irqrestore(&adapter->req_list_lock, flags);
if (!retval)
return;
zfcp_fc_gs_destroy(adapter);
zfcp_erp_thread_kill(adapter);
zfcp_destroy_adapter_work_queue(adapter);
zfcp_dbf_adapter_unregister(adapter->dbf);
zfcp_free_low_mem_buffers(adapter);
zfcp_qdio_destroy(adapter->qdio);
kfree(adapter->req_list);
kfree(adapter->fc_stats);
kfree(adapter->stats_reset_data);
kfree(adapter);
}
static void zfcp_sysfs_port_release(struct device *dev)
{
kfree(container_of(dev, struct zfcp_port, sysfs_device));
}
/**
* zfcp_port_enqueue - enqueue port to port list of adapter
* @adapter: adapter where remote port is added
* @wwpn: WWPN of the remote port to be enqueued
* @status: initial status for the port
* @d_id: destination id of the remote port to be enqueued
* Returns: pointer to enqueued port on success, ERR_PTR on error
* Locks: config_mutex must be held to serialize changes to the port list
*
* All port internal structures are set up and the sysfs entry is generated.
* d_id is used to enqueue ports with a well known address like the Directory
* Service for nameserver lookup.
*/
struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
u32 status, u32 d_id)
{
struct zfcp_port *port;
read_lock_irq(&zfcp_data.config_lock);
if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
read_unlock_irq(&zfcp_data.config_lock);
return ERR_PTR(-EINVAL);
}
read_unlock_irq(&zfcp_data.config_lock);
port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
if (!port)
return ERR_PTR(-ENOMEM);
init_waitqueue_head(&port->remove_wq);
INIT_LIST_HEAD(&port->unit_list_head);
INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
port->adapter = adapter;
port->d_id = d_id;
port->wwpn = wwpn;
port->rport_task = RPORT_NONE;
/* mark port unusable as long as sysfs registration is not complete */
atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
atomic_set(&port->refcount, 0);
if (dev_set_name(&port->sysfs_device, "0x%016llx",
(unsigned long long)wwpn)) {
kfree(port);
return ERR_PTR(-ENOMEM);
}
port->sysfs_device.parent = &adapter->ccw_device->dev;
port->sysfs_device.release = zfcp_sysfs_port_release;
dev_set_drvdata(&port->sysfs_device, port);
if (device_register(&port->sysfs_device)) {
put_device(&port->sysfs_device);
return ERR_PTR(-EINVAL);
}
if (sysfs_create_group(&port->sysfs_device.kobj,
&zfcp_sysfs_port_attrs)) {
device_unregister(&port->sysfs_device);
return ERR_PTR(-EINVAL);
}
zfcp_port_get(port);
write_lock_irq(&zfcp_data.config_lock);
list_add_tail(&port->list, &adapter->port_list_head);
atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
write_unlock_irq(&zfcp_data.config_lock);
zfcp_adapter_get(adapter);
return port;
}
/**
* zfcp_port_dequeue - dequeues a port from the port list of the adapter
* @port: pointer to struct zfcp_port which should be removed
*/
void zfcp_port_dequeue(struct zfcp_port *port)
{
write_lock_irq(&zfcp_data.config_lock);
list_del(&port->list);
write_unlock_irq(&zfcp_data.config_lock);
wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
cancel_work_sync(&port->rport_work); /* usually not necessary */
zfcp_adapter_put(port->adapter);
sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
device_unregister(&port->sysfs_device);
}
/**
* zfcp_sg_free_table - free memory used by scatterlists
* @sg: pointer to scatterlist
* @count: number of scatterlist which are to be free'ed
* the scatterlist are expected to reference pages always
*/
void zfcp_sg_free_table(struct scatterlist *sg, int count)
{
int i;
for (i = 0; i < count; i++, sg++)
if (sg)
free_page((unsigned long) sg_virt(sg));
else
break;
}
/**
* zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
* @sg: pointer to struct scatterlist
* @count: number of scatterlists which should be assigned with buffers
* of size page
*
* Returns: 0 on success, -ENOMEM otherwise
*/
int zfcp_sg_setup_table(struct scatterlist *sg, int count)
{
void *addr;
int i;
sg_init_table(sg, count);
for (i = 0; i < count; i++, sg++) {
addr = (void *) get_zeroed_page(GFP_KERNEL);
if (!addr) {
zfcp_sg_free_table(sg, i);
return -ENOMEM;
}
sg_set_buf(sg, addr, PAGE_SIZE);
}
return 0;
}
