V4L/DVB (8866): Add dummy FE to the Kconfig-file and fix it
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / s390 / scsi / zfcp_aux.c
blob3b56220fb900291df60b56284191b6e66119a02d
1 /*
2 * zfcp device driver
4 * Module interface and handling of zfcp data structures.
6 * Copyright IBM Corporation 2002, 2008
7 */
9 /*
10 * Driver authors:
11 * Martin Peschke (originator of the driver)
12 * Raimund Schroeder
13 * Aron Zeh
14 * Wolfgang Taphorn
15 * Stefan Bader
16 * Heiko Carstens (kernel 2.6 port of the driver)
17 * Andreas Herrmann
18 * Maxim Shchetynin
19 * Volker Sameske
20 * Ralph Wuerthner
21 * Michael Loehr
22 * Swen Schillig
23 * Christof Schmitt
24 * Martin Petermann
25 * Sven Schuetz
28 #include <linux/miscdevice.h>
29 #include "zfcp_ext.h"
31 static char *device;
33 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
34 MODULE_DESCRIPTION("FCP HBA driver");
35 MODULE_LICENSE("GPL");
37 module_param(device, charp, 0400);
38 MODULE_PARM_DESC(device, "specify initial device");
40 static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
42 int idx;
44 adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
45 GFP_KERNEL);
46 if (!adapter->req_list)
47 return -ENOMEM;
49 for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
50 INIT_LIST_HEAD(&adapter->req_list[idx]);
51 return 0;
54 /**
55 * zfcp_reqlist_isempty - is the request list empty
56 * @adapter: pointer to struct zfcp_adapter
58 * Returns: true if list is empty, false otherwise
60 int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
62 unsigned int idx;
64 for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
65 if (!list_empty(&adapter->req_list[idx]))
66 return 0;
67 return 1;
70 static int __init zfcp_device_setup(char *devstr)
72 char *token;
73 char *str;
75 if (!devstr)
76 return 0;
78 /* duplicate devstr and keep the original for sysfs presentation*/
79 str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
80 if (!str)
81 return 0;
83 strcpy(str, devstr);
85 token = strsep(&str, ",");
86 if (!token || strlen(token) >= BUS_ID_SIZE)
87 goto err_out;
88 strncpy(zfcp_data.init_busid, token, BUS_ID_SIZE);
90 token = strsep(&str, ",");
91 if (!token || strict_strtoull(token, 0,
92 (unsigned long long *) &zfcp_data.init_wwpn))
93 goto err_out;
95 token = strsep(&str, ",");
96 if (!token || strict_strtoull(token, 0,
97 (unsigned long long *) &zfcp_data.init_fcp_lun))
98 goto err_out;
100 kfree(str);
101 return 1;
103 err_out:
104 kfree(str);
105 pr_err("zfcp: %s is not a valid SCSI device\n", devstr);
106 return 0;
109 static void __init zfcp_init_device_configure(void)
111 struct zfcp_adapter *adapter;
112 struct zfcp_port *port;
113 struct zfcp_unit *unit;
115 down(&zfcp_data.config_sema);
116 read_lock_irq(&zfcp_data.config_lock);
117 adapter = zfcp_get_adapter_by_busid(zfcp_data.init_busid);
118 if (adapter)
119 zfcp_adapter_get(adapter);
120 read_unlock_irq(&zfcp_data.config_lock);
122 if (!adapter)
123 goto out_adapter;
124 port = zfcp_port_enqueue(adapter, zfcp_data.init_wwpn, 0, 0);
125 if (IS_ERR(port))
126 goto out_port;
127 unit = zfcp_unit_enqueue(port, zfcp_data.init_fcp_lun);
128 if (IS_ERR(unit))
129 goto out_unit;
130 up(&zfcp_data.config_sema);
131 ccw_device_set_online(adapter->ccw_device);
133 zfcp_erp_wait(adapter);
134 wait_event(adapter->erp_done_wqh,
135 !(atomic_read(&unit->status) &
136 ZFCP_STATUS_UNIT_SCSI_WORK_PENDING));
138 down(&zfcp_data.config_sema);
139 zfcp_unit_put(unit);
140 out_unit:
141 zfcp_port_put(port);
142 out_port:
143 zfcp_adapter_put(adapter);
144 out_adapter:
145 up(&zfcp_data.config_sema);
146 return;
149 static struct kmem_cache *zfcp_cache_create(int size, char *name)
151 int align = 1;
152 while ((size - align) > 0)
153 align <<= 1;
154 return kmem_cache_create(name , size, align, 0, NULL);
157 static int __init zfcp_module_init(void)
159 int retval = -ENOMEM;
161 zfcp_data.fsf_req_qtcb_cache = zfcp_cache_create(
162 sizeof(struct zfcp_fsf_req_qtcb), "zfcp_fsf");
163 if (!zfcp_data.fsf_req_qtcb_cache)
164 goto out;
166 zfcp_data.sr_buffer_cache = zfcp_cache_create(
167 sizeof(struct fsf_status_read_buffer), "zfcp_sr");
168 if (!zfcp_data.sr_buffer_cache)
169 goto out_sr_cache;
171 zfcp_data.gid_pn_cache = zfcp_cache_create(
172 sizeof(struct zfcp_gid_pn_data), "zfcp_gid");
173 if (!zfcp_data.gid_pn_cache)
174 goto out_gid_cache;
176 zfcp_data.work_queue = create_singlethread_workqueue("zfcp_wq");
178 INIT_LIST_HEAD(&zfcp_data.adapter_list_head);
179 sema_init(&zfcp_data.config_sema, 1);
180 rwlock_init(&zfcp_data.config_lock);
182 zfcp_data.scsi_transport_template =
183 fc_attach_transport(&zfcp_transport_functions);
184 if (!zfcp_data.scsi_transport_template)
185 goto out_transport;
187 retval = misc_register(&zfcp_cfdc_misc);
188 if (retval) {
189 pr_err("zfcp: Registering the misc device zfcp_cfdc failed\n");
190 goto out_misc;
193 retval = zfcp_ccw_register();
194 if (retval) {
195 pr_err("zfcp: The zfcp device driver could not register with "
196 "the common I/O layer\n");
197 goto out_ccw_register;
200 if (zfcp_device_setup(device))
201 zfcp_init_device_configure();
203 goto out;
205 out_ccw_register:
206 misc_deregister(&zfcp_cfdc_misc);
207 out_misc:
208 fc_release_transport(zfcp_data.scsi_transport_template);
209 out_transport:
210 kmem_cache_destroy(zfcp_data.gid_pn_cache);
211 out_gid_cache:
212 kmem_cache_destroy(zfcp_data.sr_buffer_cache);
213 out_sr_cache:
214 kmem_cache_destroy(zfcp_data.fsf_req_qtcb_cache);
215 out:
216 return retval;
219 module_init(zfcp_module_init);
222 * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
223 * @port: pointer to port to search for unit
224 * @fcp_lun: FCP LUN to search for
226 * Returns: pointer to zfcp_unit or NULL
228 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
230 struct zfcp_unit *unit;
232 list_for_each_entry(unit, &port->unit_list_head, list)
233 if ((unit->fcp_lun == fcp_lun) &&
234 !(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
235 return unit;
236 return NULL;
240 * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
241 * @adapter: pointer to adapter to search for port
242 * @wwpn: wwpn to search for
244 * Returns: pointer to zfcp_port or NULL
246 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
247 u64 wwpn)
249 struct zfcp_port *port;
251 list_for_each_entry(port, &adapter->port_list_head, list)
252 if ((port->wwpn == wwpn) && !(atomic_read(&port->status) &
253 (ZFCP_STATUS_PORT_NO_WWPN | ZFCP_STATUS_COMMON_REMOVE)))
254 return port;
255 return NULL;
258 static void zfcp_sysfs_unit_release(struct device *dev)
260 kfree(container_of(dev, struct zfcp_unit, sysfs_device));
264 * zfcp_unit_enqueue - enqueue unit to unit list of a port.
265 * @port: pointer to port where unit is added
266 * @fcp_lun: FCP LUN of unit to be enqueued
267 * Returns: pointer to enqueued unit on success, ERR_PTR on error
268 * Locks: config_sema must be held to serialize changes to the unit list
270 * Sets up some unit internal structures and creates sysfs entry.
272 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
274 struct zfcp_unit *unit;
276 unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
277 if (!unit)
278 return ERR_PTR(-ENOMEM);
280 atomic_set(&unit->refcount, 0);
281 init_waitqueue_head(&unit->remove_wq);
283 unit->port = port;
284 unit->fcp_lun = fcp_lun;
286 dev_set_name(&unit->sysfs_device, "0x%016llx",
287 (unsigned long long) fcp_lun);
288 unit->sysfs_device.parent = &port->sysfs_device;
289 unit->sysfs_device.release = zfcp_sysfs_unit_release;
290 dev_set_drvdata(&unit->sysfs_device, unit);
292 /* mark unit unusable as long as sysfs registration is not complete */
293 atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
295 spin_lock_init(&unit->latencies.lock);
296 unit->latencies.write.channel.min = 0xFFFFFFFF;
297 unit->latencies.write.fabric.min = 0xFFFFFFFF;
298 unit->latencies.read.channel.min = 0xFFFFFFFF;
299 unit->latencies.read.fabric.min = 0xFFFFFFFF;
300 unit->latencies.cmd.channel.min = 0xFFFFFFFF;
301 unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
303 read_lock_irq(&zfcp_data.config_lock);
304 if (zfcp_get_unit_by_lun(port, fcp_lun)) {
305 read_unlock_irq(&zfcp_data.config_lock);
306 goto err_out_free;
308 read_unlock_irq(&zfcp_data.config_lock);
310 if (device_register(&unit->sysfs_device))
311 goto err_out_free;
313 if (sysfs_create_group(&unit->sysfs_device.kobj,
314 &zfcp_sysfs_unit_attrs)) {
315 device_unregister(&unit->sysfs_device);
316 return ERR_PTR(-EIO);
319 zfcp_unit_get(unit);
321 write_lock_irq(&zfcp_data.config_lock);
322 list_add_tail(&unit->list, &port->unit_list_head);
323 atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
324 atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
326 write_unlock_irq(&zfcp_data.config_lock);
328 zfcp_port_get(port);
330 return unit;
332 err_out_free:
333 kfree(unit);
334 return ERR_PTR(-EINVAL);
338 * zfcp_unit_dequeue - dequeue unit
339 * @unit: pointer to zfcp_unit
341 * waits until all work is done on unit and removes it then from the unit->list
342 * of the associated port.
344 void zfcp_unit_dequeue(struct zfcp_unit *unit)
346 wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
347 write_lock_irq(&zfcp_data.config_lock);
348 list_del(&unit->list);
349 write_unlock_irq(&zfcp_data.config_lock);
350 zfcp_port_put(unit->port);
351 sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
352 device_unregister(&unit->sysfs_device);
355 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
357 /* must only be called with zfcp_data.config_sema taken */
358 adapter->pool.fsf_req_erp =
359 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
360 if (!adapter->pool.fsf_req_erp)
361 return -ENOMEM;
363 adapter->pool.fsf_req_scsi =
364 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
365 if (!adapter->pool.fsf_req_scsi)
366 return -ENOMEM;
368 adapter->pool.fsf_req_abort =
369 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
370 if (!adapter->pool.fsf_req_abort)
371 return -ENOMEM;
373 adapter->pool.fsf_req_status_read =
374 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
375 sizeof(struct zfcp_fsf_req));
376 if (!adapter->pool.fsf_req_status_read)
377 return -ENOMEM;
379 adapter->pool.data_status_read =
380 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
381 zfcp_data.sr_buffer_cache);
382 if (!adapter->pool.data_status_read)
383 return -ENOMEM;
385 adapter->pool.data_gid_pn =
386 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
387 if (!adapter->pool.data_gid_pn)
388 return -ENOMEM;
390 return 0;
393 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
395 /* zfcp_data.config_sema must be held */
396 if (adapter->pool.fsf_req_erp)
397 mempool_destroy(adapter->pool.fsf_req_erp);
398 if (adapter->pool.fsf_req_scsi)
399 mempool_destroy(adapter->pool.fsf_req_scsi);
400 if (adapter->pool.fsf_req_abort)
401 mempool_destroy(adapter->pool.fsf_req_abort);
402 if (adapter->pool.fsf_req_status_read)
403 mempool_destroy(adapter->pool.fsf_req_status_read);
404 if (adapter->pool.data_status_read)
405 mempool_destroy(adapter->pool.data_status_read);
406 if (adapter->pool.data_gid_pn)
407 mempool_destroy(adapter->pool.data_gid_pn);
411 * zfcp_status_read_refill - refill the long running status_read_requests
412 * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
414 * Returns: 0 on success, 1 otherwise
416 * if there are 16 or more status_read requests missing an adapter_reopen
417 * is triggered
419 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
421 while (atomic_read(&adapter->stat_miss) > 0)
422 if (zfcp_fsf_status_read(adapter)) {
423 if (atomic_read(&adapter->stat_miss) >= 16) {
424 zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
425 return 1;
427 break;
428 } else
429 atomic_dec(&adapter->stat_miss);
430 return 0;
433 static void _zfcp_status_read_scheduler(struct work_struct *work)
435 zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
436 stat_work));
440 * zfcp_adapter_enqueue - enqueue a new adapter to the list
441 * @ccw_device: pointer to the struct cc_device
443 * Returns: 0 if a new adapter was successfully enqueued
444 * -ENOMEM if alloc failed
445 * Enqueues an adapter at the end of the adapter list in the driver data.
446 * All adapter internal structures are set up.
447 * Proc-fs entries are also created.
448 * locks: config_sema must be held to serialise changes to the adapter list
450 int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
452 struct zfcp_adapter *adapter;
455 * Note: It is safe to release the list_lock, as any list changes
456 * are protected by the config_sema, which must be held to get here
459 adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
460 if (!adapter)
461 return -ENOMEM;
463 ccw_device->handler = NULL;
464 adapter->ccw_device = ccw_device;
465 atomic_set(&adapter->refcount, 0);
467 if (zfcp_qdio_allocate(adapter))
468 goto qdio_allocate_failed;
470 if (zfcp_allocate_low_mem_buffers(adapter))
471 goto failed_low_mem_buffers;
473 if (zfcp_reqlist_alloc(adapter))
474 goto failed_low_mem_buffers;
476 if (zfcp_adapter_debug_register(adapter))
477 goto debug_register_failed;
479 init_waitqueue_head(&adapter->remove_wq);
480 init_waitqueue_head(&adapter->erp_thread_wqh);
481 init_waitqueue_head(&adapter->erp_done_wqh);
483 INIT_LIST_HEAD(&adapter->port_list_head);
484 INIT_LIST_HEAD(&adapter->erp_ready_head);
485 INIT_LIST_HEAD(&adapter->erp_running_head);
487 spin_lock_init(&adapter->req_list_lock);
489 spin_lock_init(&adapter->hba_dbf_lock);
490 spin_lock_init(&adapter->san_dbf_lock);
491 spin_lock_init(&adapter->scsi_dbf_lock);
492 spin_lock_init(&adapter->rec_dbf_lock);
493 spin_lock_init(&adapter->req_q_lock);
495 rwlock_init(&adapter->erp_lock);
496 rwlock_init(&adapter->abort_lock);
498 sema_init(&adapter->erp_ready_sem, 0);
500 INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
501 INIT_WORK(&adapter->scan_work, _zfcp_scan_ports_later);
503 /* mark adapter unusable as long as sysfs registration is not complete */
504 atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
506 dev_set_drvdata(&ccw_device->dev, adapter);
508 if (sysfs_create_group(&ccw_device->dev.kobj,
509 &zfcp_sysfs_adapter_attrs))
510 goto sysfs_failed;
512 write_lock_irq(&zfcp_data.config_lock);
513 atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
514 list_add_tail(&adapter->list, &zfcp_data.adapter_list_head);
515 write_unlock_irq(&zfcp_data.config_lock);
517 zfcp_fc_nameserver_init(adapter);
519 return 0;
521 sysfs_failed:
522 zfcp_adapter_debug_unregister(adapter);
523 debug_register_failed:
524 dev_set_drvdata(&ccw_device->dev, NULL);
525 kfree(adapter->req_list);
526 failed_low_mem_buffers:
527 zfcp_free_low_mem_buffers(adapter);
528 qdio_allocate_failed:
529 zfcp_qdio_free(adapter);
530 kfree(adapter);
531 return -ENOMEM;
535 * zfcp_adapter_dequeue - remove the adapter from the resource list
536 * @adapter: pointer to struct zfcp_adapter which should be removed
537 * locks: adapter list write lock is assumed to be held by caller
539 void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
541 int retval = 0;
542 unsigned long flags;
544 cancel_work_sync(&adapter->scan_work);
545 cancel_work_sync(&adapter->stat_work);
546 zfcp_adapter_scsi_unregister(adapter);
547 sysfs_remove_group(&adapter->ccw_device->dev.kobj,
548 &zfcp_sysfs_adapter_attrs);
549 dev_set_drvdata(&adapter->ccw_device->dev, NULL);
550 /* sanity check: no pending FSF requests */
551 spin_lock_irqsave(&adapter->req_list_lock, flags);
552 retval = zfcp_reqlist_isempty(adapter);
553 spin_unlock_irqrestore(&adapter->req_list_lock, flags);
554 if (!retval)
555 return;
557 zfcp_adapter_debug_unregister(adapter);
559 /* remove specified adapter data structure from list */
560 write_lock_irq(&zfcp_data.config_lock);
561 list_del(&adapter->list);
562 write_unlock_irq(&zfcp_data.config_lock);
564 zfcp_qdio_free(adapter);
566 zfcp_free_low_mem_buffers(adapter);
567 kfree(adapter->req_list);
568 kfree(adapter->fc_stats);
569 kfree(adapter->stats_reset_data);
570 kfree(adapter);
573 static void zfcp_sysfs_port_release(struct device *dev)
575 kfree(container_of(dev, struct zfcp_port, sysfs_device));
579 * zfcp_port_enqueue - enqueue port to port list of adapter
580 * @adapter: adapter where remote port is added
581 * @wwpn: WWPN of the remote port to be enqueued
582 * @status: initial status for the port
583 * @d_id: destination id of the remote port to be enqueued
584 * Returns: pointer to enqueued port on success, ERR_PTR on error
585 * Locks: config_sema must be held to serialize changes to the port list
587 * All port internal structures are set up and the sysfs entry is generated.
588 * d_id is used to enqueue ports with a well known address like the Directory
589 * Service for nameserver lookup.
591 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
592 u32 status, u32 d_id)
594 struct zfcp_port *port;
595 int retval;
597 port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
598 if (!port)
599 return ERR_PTR(-ENOMEM);
601 init_waitqueue_head(&port->remove_wq);
602 INIT_LIST_HEAD(&port->unit_list_head);
603 INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
605 port->adapter = adapter;
606 port->d_id = d_id;
607 port->wwpn = wwpn;
609 /* mark port unusable as long as sysfs registration is not complete */
610 atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
611 atomic_set(&port->refcount, 0);
613 dev_set_name(&port->sysfs_device, "0x%016llx", wwpn);
614 port->sysfs_device.parent = &adapter->ccw_device->dev;
616 port->sysfs_device.release = zfcp_sysfs_port_release;
617 dev_set_drvdata(&port->sysfs_device, port);
619 read_lock_irq(&zfcp_data.config_lock);
620 if (!(status & ZFCP_STATUS_PORT_NO_WWPN))
621 if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
622 read_unlock_irq(&zfcp_data.config_lock);
623 goto err_out_free;
625 read_unlock_irq(&zfcp_data.config_lock);
627 if (device_register(&port->sysfs_device))
628 goto err_out_free;
630 retval = sysfs_create_group(&port->sysfs_device.kobj,
631 &zfcp_sysfs_port_attrs);
633 if (retval) {
634 device_unregister(&port->sysfs_device);
635 goto err_out;
638 zfcp_port_get(port);
640 write_lock_irq(&zfcp_data.config_lock);
641 list_add_tail(&port->list, &adapter->port_list_head);
642 atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
643 atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
645 write_unlock_irq(&zfcp_data.config_lock);
647 zfcp_adapter_get(adapter);
648 return port;
650 err_out_free:
651 kfree(port);
652 err_out:
653 return ERR_PTR(-EINVAL);
657 * zfcp_port_dequeue - dequeues a port from the port list of the adapter
658 * @port: pointer to struct zfcp_port which should be removed
660 void zfcp_port_dequeue(struct zfcp_port *port)
662 wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
663 write_lock_irq(&zfcp_data.config_lock);
664 list_del(&port->list);
665 write_unlock_irq(&zfcp_data.config_lock);
666 if (port->rport)
667 fc_remote_port_delete(port->rport);
668 port->rport = NULL;
669 zfcp_adapter_put(port->adapter);
670 sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
671 device_unregister(&port->sysfs_device);
675 * zfcp_sg_free_table - free memory used by scatterlists
676 * @sg: pointer to scatterlist
677 * @count: number of scatterlist which are to be free'ed
678 * the scatterlist are expected to reference pages always
680 void zfcp_sg_free_table(struct scatterlist *sg, int count)
682 int i;
684 for (i = 0; i < count; i++, sg++)
685 if (sg)
686 free_page((unsigned long) sg_virt(sg));
687 else
688 break;
692 * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
693 * @sg: pointer to struct scatterlist
694 * @count: number of scatterlists which should be assigned with buffers
695 * of size page
697 * Returns: 0 on success, -ENOMEM otherwise
699 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
701 void *addr;
702 int i;
704 sg_init_table(sg, count);
705 for (i = 0; i < count; i++, sg++) {
706 addr = (void *) get_zeroed_page(GFP_KERNEL);
707 if (!addr) {
708 zfcp_sg_free_table(sg, i);
709 return -ENOMEM;
711 sg_set_buf(sg, addr, PAGE_SIZE);
713 return 0;