Version:  2.6.34 2.6.35 2.6.36 2.6.37 2.6.38 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14

Linux/drivers/scsi/ibmvscsi/ibmvscsi.c

  1 /* ------------------------------------------------------------
  2  * ibmvscsi.c
  3  * (C) Copyright IBM Corporation 1994, 2004
  4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
  5  *          Santiago Leon (santil@us.ibm.com)
  6  *          Dave Boutcher (sleddog@us.ibm.com)
  7  *
  8  * This program is free software; you can redistribute it and/or modify
  9  * it under the terms of the GNU General Public License as published by
 10  * the Free Software Foundation; either version 2 of the License, or
 11  * (at your option) any later version.
 12  *
 13  * This program is distributed in the hope that it will be useful,
 14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16  * GNU General Public License for more details.
 17  *
 18  * You should have received a copy of the GNU General Public License
 19  * along with this program; if not, write to the Free Software
 20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 21  * USA
 22  *
 23  * ------------------------------------------------------------
 24  * Emulation of a SCSI host adapter for Virtual I/O devices
 25  *
 26  * This driver supports the SCSI adapter implemented by the IBM
 27  * Power5 firmware.  That SCSI adapter is not a physical adapter,
 28  * but allows Linux SCSI peripheral drivers to directly
 29  * access devices in another logical partition on the physical system.
 30  *
 31  * The virtual adapter(s) are present in the open firmware device
 32  * tree just like real adapters.
 33  *
 34  * One of the capabilities provided on these systems is the ability
 35  * to DMA between partitions.  The architecture states that for VSCSI,
 36  * the server side is allowed to DMA to and from the client.  The client
 37  * is never trusted to DMA to or from the server directly.
 38  *
 39  * Messages are sent between partitions on a "Command/Response Queue" 
 40  * (CRQ), which is just a buffer of 16 byte entries in the receiver's 
 41  * Senders cannot access the buffer directly, but send messages by
 42  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
 43  * puts the message in the next 16 byte space in round-robin fashion,
 44  * turns on the high order bit of the message (the valid bit), and 
 45  * generates an interrupt to the receiver (if interrupts are turned on.) 
 46  * The receiver just turns off the valid bit when they have copied out
 47  * the message.
 48  *
 49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
 50  * (IU) (as defined in the T10 standard available at www.t10.org), gets 
 51  * a DMA address for the message, and sends it to the server as the
 52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
 53  * including doing any additional data transfers.  When it is done, it
 54  * DMAs the SRP response back to the same address as the request came from,
 55  * and sends a CRQ message back to inform the client that the request has
 56  * completed.
 57  *
 58  * TODO: This is currently pretty tied to the IBM pSeries hypervisor
 59  * interfaces.  It would be really nice to abstract this above an RDMA
 60  * layer.
 61  */
 62 
 63 #include <linux/module.h>
 64 #include <linux/moduleparam.h>
 65 #include <linux/dma-mapping.h>
 66 #include <linux/delay.h>
 67 #include <linux/slab.h>
 68 #include <linux/of.h>
 69 #include <linux/pm.h>
 70 #include <linux/kthread.h>
 71 #include <asm/firmware.h>
 72 #include <asm/vio.h>
 73 #include <scsi/scsi.h>
 74 #include <scsi/scsi_cmnd.h>
 75 #include <scsi/scsi_host.h>
 76 #include <scsi/scsi_device.h>
 77 #include <scsi/scsi_transport_srp.h>
 78 #include "ibmvscsi.h"
 79 
 80 /* The values below are somewhat arbitrary default values, but 
 81  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
 82  * Note that there are 3 bits of channel value, 6 bits of id, and
 83  * 5 bits of LUN.
 84  */
 85 static int max_id = 64;
 86 static int max_channel = 3;
 87 static int init_timeout = 300;
 88 static int login_timeout = 60;
 89 static int info_timeout = 30;
 90 static int abort_timeout = 60;
 91 static int reset_timeout = 60;
 92 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
 93 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
 94 static int fast_fail = 1;
 95 static int client_reserve = 1;
 96 static char partition_name[97] = "UNKNOWN";
 97 static unsigned int partition_number = -1;
 98 
 99 static struct scsi_transport_template *ibmvscsi_transport_template;
100 
101 #define IBMVSCSI_VERSION "1.5.9"
102 
103 MODULE_DESCRIPTION("IBM Virtual SCSI");
104 MODULE_AUTHOR("Dave Boutcher");
105 MODULE_LICENSE("GPL");
106 MODULE_VERSION(IBMVSCSI_VERSION);
107 
108 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
109 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
110 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
111 MODULE_PARM_DESC(max_channel, "Largest channel value");
112 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
113 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
114 module_param_named(max_requests, max_requests, int, S_IRUGO);
115 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
116 module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
117 MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
118 module_param_named(client_reserve, client_reserve, int, S_IRUGO );
119 MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
120 
121 static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
122                                 struct ibmvscsi_host_data *hostdata);
123 
124 /* ------------------------------------------------------------
125  * Routines for managing the command/response queue
126  */
127 /**
128  * ibmvscsi_handle_event: - Interrupt handler for crq events
129  * @irq:        number of irq to handle, not used
130  * @dev_instance: ibmvscsi_host_data of host that received interrupt
131  *
132  * Disables interrupts and schedules srp_task
133  * Always returns IRQ_HANDLED
134  */
135 static irqreturn_t ibmvscsi_handle_event(int irq, void *dev_instance)
136 {
137         struct ibmvscsi_host_data *hostdata =
138             (struct ibmvscsi_host_data *)dev_instance;
139         vio_disable_interrupts(to_vio_dev(hostdata->dev));
140         tasklet_schedule(&hostdata->srp_task);
141         return IRQ_HANDLED;
142 }
143 
144 /**
145  * release_crq_queue: - Deallocates data and unregisters CRQ
146  * @queue:      crq_queue to initialize and register
147  * @host_data:  ibmvscsi_host_data of host
148  *
149  * Frees irq, deallocates a page for messages, unmaps dma, and unregisters
150  * the crq with the hypervisor.
151  */
152 static void ibmvscsi_release_crq_queue(struct crq_queue *queue,
153                                        struct ibmvscsi_host_data *hostdata,
154                                        int max_requests)
155 {
156         long rc = 0;
157         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
158         free_irq(vdev->irq, (void *)hostdata);
159         tasklet_kill(&hostdata->srp_task);
160         do {
161                 if (rc)
162                         msleep(100);
163                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
164         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
165         dma_unmap_single(hostdata->dev,
166                          queue->msg_token,
167                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
168         free_page((unsigned long)queue->msgs);
169 }
170 
171 /**
172  * crq_queue_next_crq: - Returns the next entry in message queue
173  * @queue:      crq_queue to use
174  *
175  * Returns pointer to next entry in queue, or NULL if there are no new
176  * entried in the CRQ.
177  */
178 static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
179 {
180         struct viosrp_crq *crq;
181         unsigned long flags;
182 
183         spin_lock_irqsave(&queue->lock, flags);
184         crq = &queue->msgs[queue->cur];
185         if (crq->valid & 0x80) {
186                 if (++queue->cur == queue->size)
187                         queue->cur = 0;
188         } else
189                 crq = NULL;
190         spin_unlock_irqrestore(&queue->lock, flags);
191 
192         return crq;
193 }
194 
195 /**
196  * ibmvscsi_send_crq: - Send a CRQ
197  * @hostdata:   the adapter
198  * @word1:      the first 64 bits of the data
199  * @word2:      the second 64 bits of the data
200  */
201 static int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
202                              u64 word1, u64 word2)
203 {
204         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
205 
206         return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
207 }
208 
209 /**
210  * ibmvscsi_task: - Process srps asynchronously
211  * @data:       ibmvscsi_host_data of host
212  */
213 static void ibmvscsi_task(void *data)
214 {
215         struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data;
216         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
217         struct viosrp_crq *crq;
218         int done = 0;
219 
220         while (!done) {
221                 /* Pull all the valid messages off the CRQ */
222                 while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
223                         ibmvscsi_handle_crq(crq, hostdata);
224                         crq->valid = 0x00;
225                 }
226 
227                 vio_enable_interrupts(vdev);
228                 crq = crq_queue_next_crq(&hostdata->queue);
229                 if (crq != NULL) {
230                         vio_disable_interrupts(vdev);
231                         ibmvscsi_handle_crq(crq, hostdata);
232                         crq->valid = 0x00;
233                 } else {
234                         done = 1;
235                 }
236         }
237 }
238 
239 static void gather_partition_info(void)
240 {
241         struct device_node *rootdn;
242 
243         const char *ppartition_name;
244         const __be32 *p_number_ptr;
245 
246         /* Retrieve information about this partition */
247         rootdn = of_find_node_by_path("/");
248         if (!rootdn) {
249                 return;
250         }
251 
252         ppartition_name = of_get_property(rootdn, "ibm,partition-name", NULL);
253         if (ppartition_name)
254                 strncpy(partition_name, ppartition_name,
255                                 sizeof(partition_name));
256         p_number_ptr = of_get_property(rootdn, "ibm,partition-no", NULL);
257         if (p_number_ptr)
258                 partition_number = of_read_number(p_number_ptr, 1);
259         of_node_put(rootdn);
260 }
261 
262 static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
263 {
264         memset(&hostdata->madapter_info, 0x00,
265                         sizeof(hostdata->madapter_info));
266 
267         dev_info(hostdata->dev, "SRP_VERSION: %s\n", SRP_VERSION);
268         strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);
269 
270         strncpy(hostdata->madapter_info.partition_name, partition_name,
271                         sizeof(hostdata->madapter_info.partition_name));
272 
273         hostdata->madapter_info.partition_number =
274                                         cpu_to_be32(partition_number);
275 
276         hostdata->madapter_info.mad_version = cpu_to_be32(1);
277         hostdata->madapter_info.os_type = cpu_to_be32(2);
278 }
279 
280 /**
281  * reset_crq_queue: - resets a crq after a failure
282  * @queue:      crq_queue to initialize and register
283  * @hostdata:   ibmvscsi_host_data of host
284  *
285  */
286 static int ibmvscsi_reset_crq_queue(struct crq_queue *queue,
287                                     struct ibmvscsi_host_data *hostdata)
288 {
289         int rc = 0;
290         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
291 
292         /* Close the CRQ */
293         do {
294                 if (rc)
295                         msleep(100);
296                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
297         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
298 
299         /* Clean out the queue */
300         memset(queue->msgs, 0x00, PAGE_SIZE);
301         queue->cur = 0;
302 
303         set_adapter_info(hostdata);
304 
305         /* And re-open it again */
306         rc = plpar_hcall_norets(H_REG_CRQ,
307                                 vdev->unit_address,
308                                 queue->msg_token, PAGE_SIZE);
309         if (rc == 2) {
310                 /* Adapter is good, but other end is not ready */
311                 dev_warn(hostdata->dev, "Partner adapter not ready\n");
312         } else if (rc != 0) {
313                 dev_warn(hostdata->dev, "couldn't register crq--rc 0x%x\n", rc);
314         }
315         return rc;
316 }
317 
318 /**
319  * initialize_crq_queue: - Initializes and registers CRQ with hypervisor
320  * @queue:      crq_queue to initialize and register
321  * @hostdata:   ibmvscsi_host_data of host
322  *
323  * Allocates a page for messages, maps it for dma, and registers
324  * the crq with the hypervisor.
325  * Returns zero on success.
326  */
327 static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
328                                    struct ibmvscsi_host_data *hostdata,
329                                    int max_requests)
330 {
331         int rc;
332         int retrc;
333         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
334 
335         queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
336 
337         if (!queue->msgs)
338                 goto malloc_failed;
339         queue->size = PAGE_SIZE / sizeof(*queue->msgs);
340 
341         queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
342                                           queue->size * sizeof(*queue->msgs),
343                                           DMA_BIDIRECTIONAL);
344 
345         if (dma_mapping_error(hostdata->dev, queue->msg_token))
346                 goto map_failed;
347 
348         gather_partition_info();
349         set_adapter_info(hostdata);
350 
351         retrc = rc = plpar_hcall_norets(H_REG_CRQ,
352                                 vdev->unit_address,
353                                 queue->msg_token, PAGE_SIZE);
354         if (rc == H_RESOURCE)
355                 /* maybe kexecing and resource is busy. try a reset */
356                 rc = ibmvscsi_reset_crq_queue(queue,
357                                               hostdata);
358 
359         if (rc == 2) {
360                 /* Adapter is good, but other end is not ready */
361                 dev_warn(hostdata->dev, "Partner adapter not ready\n");
362                 retrc = 0;
363         } else if (rc != 0) {
364                 dev_warn(hostdata->dev, "Error %d opening adapter\n", rc);
365                 goto reg_crq_failed;
366         }
367 
368         queue->cur = 0;
369         spin_lock_init(&queue->lock);
370 
371         tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
372                      (unsigned long)hostdata);
373 
374         if (request_irq(vdev->irq,
375                         ibmvscsi_handle_event,
376                         0, "ibmvscsi", (void *)hostdata) != 0) {
377                 dev_err(hostdata->dev, "couldn't register irq 0x%x\n",
378                         vdev->irq);
379                 goto req_irq_failed;
380         }
381 
382         rc = vio_enable_interrupts(vdev);
383         if (rc != 0) {
384                 dev_err(hostdata->dev, "Error %d enabling interrupts!!!\n", rc);
385                 goto req_irq_failed;
386         }
387 
388         return retrc;
389 
390       req_irq_failed:
391         tasklet_kill(&hostdata->srp_task);
392         rc = 0;
393         do {
394                 if (rc)
395                         msleep(100);
396                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
397         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
398       reg_crq_failed:
399         dma_unmap_single(hostdata->dev,
400                          queue->msg_token,
401                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
402       map_failed:
403         free_page((unsigned long)queue->msgs);
404       malloc_failed:
405         return -1;
406 }
407 
408 /**
409  * reenable_crq_queue: - reenables a crq after
410  * @queue:      crq_queue to initialize and register
411  * @hostdata:   ibmvscsi_host_data of host
412  *
413  */
414 static int ibmvscsi_reenable_crq_queue(struct crq_queue *queue,
415                                        struct ibmvscsi_host_data *hostdata)
416 {
417         int rc = 0;
418         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
419 
420         /* Re-enable the CRQ */
421         do {
422                 if (rc)
423                         msleep(100);
424                 rc = plpar_hcall_norets(H_ENABLE_CRQ, vdev->unit_address);
425         } while ((rc == H_IN_PROGRESS) || (rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
426 
427         if (rc)
428                 dev_err(hostdata->dev, "Error %d enabling adapter\n", rc);
429         return rc;
430 }
431 
432 /* ------------------------------------------------------------
433  * Routines for the event pool and event structs
434  */
435 /**
436  * initialize_event_pool: - Allocates and initializes the event pool for a host
437  * @pool:       event_pool to be initialized
438  * @size:       Number of events in pool
439  * @hostdata:   ibmvscsi_host_data who owns the event pool
440  *
441  * Returns zero on success.
442 */
443 static int initialize_event_pool(struct event_pool *pool,
444                                  int size, struct ibmvscsi_host_data *hostdata)
445 {
446         int i;
447 
448         pool->size = size;
449         pool->next = 0;
450         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
451         if (!pool->events)
452                 return -ENOMEM;
453 
454         pool->iu_storage =
455             dma_alloc_coherent(hostdata->dev,
456                                pool->size * sizeof(*pool->iu_storage),
457                                &pool->iu_token, 0);
458         if (!pool->iu_storage) {
459                 kfree(pool->events);
460                 return -ENOMEM;
461         }
462 
463         for (i = 0; i < pool->size; ++i) {
464                 struct srp_event_struct *evt = &pool->events[i];
465                 memset(&evt->crq, 0x00, sizeof(evt->crq));
466                 atomic_set(&evt->free, 1);
467                 evt->crq.valid = 0x80;
468                 evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
469                 evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
470                         sizeof(*evt->xfer_iu) * i);
471                 evt->xfer_iu = pool->iu_storage + i;
472                 evt->hostdata = hostdata;
473                 evt->ext_list = NULL;
474                 evt->ext_list_token = 0;
475         }
476 
477         return 0;
478 }
479 
480 /**
481  * release_event_pool: - Frees memory of an event pool of a host
482  * @pool:       event_pool to be released
483  * @hostdata:   ibmvscsi_host_data who owns the even pool
484  *
485  * Returns zero on success.
486 */
487 static void release_event_pool(struct event_pool *pool,
488                                struct ibmvscsi_host_data *hostdata)
489 {
490         int i, in_use = 0;
491         for (i = 0; i < pool->size; ++i) {
492                 if (atomic_read(&pool->events[i].free) != 1)
493                         ++in_use;
494                 if (pool->events[i].ext_list) {
495                         dma_free_coherent(hostdata->dev,
496                                   SG_ALL * sizeof(struct srp_direct_buf),
497                                   pool->events[i].ext_list,
498                                   pool->events[i].ext_list_token);
499                 }
500         }
501         if (in_use)
502                 dev_warn(hostdata->dev, "releasing event pool with %d "
503                          "events still in use?\n", in_use);
504         kfree(pool->events);
505         dma_free_coherent(hostdata->dev,
506                           pool->size * sizeof(*pool->iu_storage),
507                           pool->iu_storage, pool->iu_token);
508 }
509 
510 /**
511  * valid_event_struct: - Determines if event is valid.
512  * @pool:       event_pool that contains the event
513  * @evt:        srp_event_struct to be checked for validity
514  *
515  * Returns zero if event is invalid, one otherwise.
516 */
517 static int valid_event_struct(struct event_pool *pool,
518                                 struct srp_event_struct *evt)
519 {
520         int index = evt - pool->events;
521         if (index < 0 || index >= pool->size)   /* outside of bounds */
522                 return 0;
523         if (evt != pool->events + index)        /* unaligned */
524                 return 0;
525         return 1;
526 }
527 
528 /**
529  * ibmvscsi_free-event_struct: - Changes status of event to "free"
530  * @pool:       event_pool that contains the event
531  * @evt:        srp_event_struct to be modified
532  *
533 */
534 static void free_event_struct(struct event_pool *pool,
535                                        struct srp_event_struct *evt)
536 {
537         if (!valid_event_struct(pool, evt)) {
538                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
539                         "(not in pool %p)\n", evt, pool->events);
540                 return;
541         }
542         if (atomic_inc_return(&evt->free) != 1) {
543                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
544                         "which is not in use!\n", evt);
545                 return;
546         }
547 }
548 
549 /**
550  * get_evt_struct: - Gets the next free event in pool
551  * @pool:       event_pool that contains the events to be searched
552  *
553  * Returns the next event in "free" state, and NULL if none are free.
554  * Note that no synchronization is done here, we assume the host_lock
555  * will syncrhonze things.
556 */
557 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
558 {
559         int i;
560         int poolsize = pool->size;
561         int offset = pool->next;
562 
563         for (i = 0; i < poolsize; i++) {
564                 offset = (offset + 1) % poolsize;
565                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
566                         pool->next = offset;
567                         return &pool->events[offset];
568                 }
569         }
570 
571         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
572         return NULL;
573 }
574 
575 /**
576  * init_event_struct: Initialize fields in an event struct that are always 
577  *                    required.
578  * @evt:        The event
579  * @done:       Routine to call when the event is responded to
580  * @format:     SRP or MAD format
581  * @timeout:    timeout value set in the CRQ
582  */
583 static void init_event_struct(struct srp_event_struct *evt_struct,
584                               void (*done) (struct srp_event_struct *),
585                               u8 format,
586                               int timeout)
587 {
588         evt_struct->cmnd = NULL;
589         evt_struct->cmnd_done = NULL;
590         evt_struct->sync_srp = NULL;
591         evt_struct->crq.format = format;
592         evt_struct->crq.timeout = cpu_to_be16(timeout);
593         evt_struct->done = done;
594 }
595 
596 /* ------------------------------------------------------------
597  * Routines for receiving SCSI responses from the hosting partition
598  */
599 
600 /**
601  * set_srp_direction: Set the fields in the srp related to data
602  *     direction and number of buffers based on the direction in
603  *     the scsi_cmnd and the number of buffers
604  */
605 static void set_srp_direction(struct scsi_cmnd *cmd,
606                               struct srp_cmd *srp_cmd, 
607                               int numbuf)
608 {
609         u8 fmt;
610 
611         if (numbuf == 0)
612                 return;
613         
614         if (numbuf == 1)
615                 fmt = SRP_DATA_DESC_DIRECT;
616         else {
617                 fmt = SRP_DATA_DESC_INDIRECT;
618                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
619 
620                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
621                         srp_cmd->data_out_desc_cnt = numbuf;
622                 else
623                         srp_cmd->data_in_desc_cnt = numbuf;
624         }
625 
626         if (cmd->sc_data_direction == DMA_TO_DEVICE)
627                 srp_cmd->buf_fmt = fmt << 4;
628         else
629                 srp_cmd->buf_fmt = fmt;
630 }
631 
632 /**
633  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
634  * @cmd:        srp_cmd whose additional_data member will be unmapped
635  * @dev:        device for which the memory is mapped
636  *
637 */
638 static void unmap_cmd_data(struct srp_cmd *cmd,
639                            struct srp_event_struct *evt_struct,
640                            struct device *dev)
641 {
642         u8 out_fmt, in_fmt;
643 
644         out_fmt = cmd->buf_fmt >> 4;
645         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
646 
647         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
648                 return;
649 
650         if (evt_struct->cmnd)
651                 scsi_dma_unmap(evt_struct->cmnd);
652 }
653 
654 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
655                        struct srp_direct_buf *md)
656 {
657         int i;
658         struct scatterlist *sg;
659         u64 total_length = 0;
660 
661         scsi_for_each_sg(cmd, sg, nseg, i) {
662                 struct srp_direct_buf *descr = md + i;
663                 descr->va = cpu_to_be64(sg_dma_address(sg));
664                 descr->len = cpu_to_be32(sg_dma_len(sg));
665                 descr->key = 0;
666                 total_length += sg_dma_len(sg);
667         }
668         return total_length;
669 }
670 
671 /**
672  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
673  * @cmd:        Scsi_Cmnd with the scatterlist
674  * @srp_cmd:    srp_cmd that contains the memory descriptor
675  * @dev:        device for which to map dma memory
676  *
677  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
678  * Returns 1 on success.
679 */
680 static int map_sg_data(struct scsi_cmnd *cmd,
681                        struct srp_event_struct *evt_struct,
682                        struct srp_cmd *srp_cmd, struct device *dev)
683 {
684 
685         int sg_mapped;
686         u64 total_length = 0;
687         struct srp_direct_buf *data =
688                 (struct srp_direct_buf *) srp_cmd->add_data;
689         struct srp_indirect_buf *indirect =
690                 (struct srp_indirect_buf *) data;
691 
692         sg_mapped = scsi_dma_map(cmd);
693         if (!sg_mapped)
694                 return 1;
695         else if (sg_mapped < 0)
696                 return 0;
697 
698         set_srp_direction(cmd, srp_cmd, sg_mapped);
699 
700         /* special case; we can use a single direct descriptor */
701         if (sg_mapped == 1) {
702                 map_sg_list(cmd, sg_mapped, data);
703                 return 1;
704         }
705 
706         indirect->table_desc.va = 0;
707         indirect->table_desc.len = cpu_to_be32(sg_mapped *
708                                                sizeof(struct srp_direct_buf));
709         indirect->table_desc.key = 0;
710 
711         if (sg_mapped <= MAX_INDIRECT_BUFS) {
712                 total_length = map_sg_list(cmd, sg_mapped,
713                                            &indirect->desc_list[0]);
714                 indirect->len = cpu_to_be32(total_length);
715                 return 1;
716         }
717 
718         /* get indirect table */
719         if (!evt_struct->ext_list) {
720                 evt_struct->ext_list = (struct srp_direct_buf *)
721                         dma_alloc_coherent(dev,
722                                            SG_ALL * sizeof(struct srp_direct_buf),
723                                            &evt_struct->ext_list_token, 0);
724                 if (!evt_struct->ext_list) {
725                         if (!firmware_has_feature(FW_FEATURE_CMO))
726                                 sdev_printk(KERN_ERR, cmd->device,
727                                             "Can't allocate memory "
728                                             "for indirect table\n");
729                         scsi_dma_unmap(cmd);
730                         return 0;
731                 }
732         }
733 
734         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
735 
736         indirect->len = cpu_to_be32(total_length);
737         indirect->table_desc.va = cpu_to_be64(evt_struct->ext_list_token);
738         indirect->table_desc.len = cpu_to_be32(sg_mapped *
739                                                sizeof(indirect->desc_list[0]));
740         memcpy(indirect->desc_list, evt_struct->ext_list,
741                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
742         return 1;
743 }
744 
745 /**
746  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
747  * @cmd:        struct scsi_cmnd with the memory to be mapped
748  * @srp_cmd:    srp_cmd that contains the memory descriptor
749  * @dev:        dma device for which to map dma memory
750  *
751  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds 
752  * Returns 1 on success.
753 */
754 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
755                                 struct srp_event_struct *evt_struct,
756                                 struct srp_cmd *srp_cmd, struct device *dev)
757 {
758         switch (cmd->sc_data_direction) {
759         case DMA_FROM_DEVICE:
760         case DMA_TO_DEVICE:
761                 break;
762         case DMA_NONE:
763                 return 1;
764         case DMA_BIDIRECTIONAL:
765                 sdev_printk(KERN_ERR, cmd->device,
766                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
767                 return 0;
768         default:
769                 sdev_printk(KERN_ERR, cmd->device,
770                             "Unknown data direction 0x%02x; can't map!\n",
771                             cmd->sc_data_direction);
772                 return 0;
773         }
774 
775         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
776 }
777 
778 /**
779  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
780  * @hostdata:    the adapter
781  */
782 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
783 {
784         struct srp_event_struct *evt;
785         unsigned long flags;
786 
787         spin_lock_irqsave(hostdata->host->host_lock, flags);
788         while (!list_empty(&hostdata->sent)) {
789                 evt = list_first_entry(&hostdata->sent, struct srp_event_struct, list);
790                 list_del(&evt->list);
791                 del_timer(&evt->timer);
792 
793                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
794                 if (evt->cmnd) {
795                         evt->cmnd->result = (error_code << 16);
796                         unmap_cmd_data(&evt->iu.srp.cmd, evt,
797                                        evt->hostdata->dev);
798                         if (evt->cmnd_done)
799                                 evt->cmnd_done(evt->cmnd);
800                 } else if (evt->done)
801                         evt->done(evt);
802                 free_event_struct(&evt->hostdata->pool, evt);
803                 spin_lock_irqsave(hostdata->host->host_lock, flags);
804         }
805         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
806 }
807 
808 /**
809  * ibmvscsi_reset_host - Reset the connection to the server
810  * @hostdata:   struct ibmvscsi_host_data to reset
811 */
812 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
813 {
814         scsi_block_requests(hostdata->host);
815         atomic_set(&hostdata->request_limit, 0);
816 
817         purge_requests(hostdata, DID_ERROR);
818         hostdata->reset_crq = 1;
819         wake_up(&hostdata->work_wait_q);
820 }
821 
822 /**
823  * ibmvscsi_timeout - Internal command timeout handler
824  * @evt_struct: struct srp_event_struct that timed out
825  *
826  * Called when an internally generated command times out
827 */
828 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
829 {
830         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
831 
832         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
833                 evt_struct->iu.srp.cmd.opcode);
834 
835         ibmvscsi_reset_host(hostdata);
836 }
837 
838 
839 /* ------------------------------------------------------------
840  * Routines for sending and receiving SRPs
841  */
842 /**
843  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
844  * @evt_struct: evt_struct to be sent
845  * @hostdata:   ibmvscsi_host_data of host
846  * @timeout:    timeout in seconds - 0 means do not time command
847  *
848  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
849  * Note that this routine assumes that host_lock is held for synchronization
850 */
851 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
852                                    struct ibmvscsi_host_data *hostdata,
853                                    unsigned long timeout)
854 {
855         __be64 *crq_as_u64 = (__be64 *)&evt_struct->crq;
856         int request_status = 0;
857         int rc;
858         int srp_req = 0;
859 
860         /* If we have exhausted our request limit, just fail this request,
861          * unless it is for a reset or abort.
862          * Note that there are rare cases involving driver generated requests 
863          * (such as task management requests) that the mid layer may think we
864          * can handle more requests (can_queue) when we actually can't
865          */
866         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
867                 srp_req = 1;
868                 request_status =
869                         atomic_dec_if_positive(&hostdata->request_limit);
870                 /* If request limit was -1 when we started, it is now even
871                  * less than that
872                  */
873                 if (request_status < -1)
874                         goto send_error;
875                 /* Otherwise, we may have run out of requests. */
876                 /* If request limit was 0 when we started the adapter is in the
877                  * process of performing a login with the server adapter, or
878                  * we may have run out of requests.
879                  */
880                 else if (request_status == -1 &&
881                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
882                         goto send_busy;
883                 /* Abort and reset calls should make it through.
884                  * Nothing except abort and reset should use the last two
885                  * slots unless we had two or less to begin with.
886                  */
887                 else if (request_status < 2 &&
888                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
889                         /* In the case that we have less than two requests
890                          * available, check the server limit as a combination
891                          * of the request limit and the number of requests
892                          * in-flight (the size of the send list).  If the
893                          * server limit is greater than 2, return busy so
894                          * that the last two are reserved for reset and abort.
895                          */
896                         int server_limit = request_status;
897                         struct srp_event_struct *tmp_evt;
898 
899                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
900                                 server_limit++;
901                         }
902 
903                         if (server_limit > 2)
904                                 goto send_busy;
905                 }
906         }
907 
908         /* Copy the IU into the transfer area */
909         *evt_struct->xfer_iu = evt_struct->iu;
910         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
911 
912         /* Add this to the sent list.  We need to do this 
913          * before we actually send 
914          * in case it comes back REALLY fast
915          */
916         list_add_tail(&evt_struct->list, &hostdata->sent);
917 
918         init_timer(&evt_struct->timer);
919         if (timeout) {
920                 evt_struct->timer.data = (unsigned long) evt_struct;
921                 evt_struct->timer.expires = jiffies + (timeout * HZ);
922                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
923                 add_timer(&evt_struct->timer);
924         }
925 
926         rc = ibmvscsi_send_crq(hostdata, be64_to_cpu(crq_as_u64[0]),
927                                be64_to_cpu(crq_as_u64[1]));
928         if (rc != 0) {
929                 list_del(&evt_struct->list);
930                 del_timer(&evt_struct->timer);
931 
932                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
933                  * Firmware will send a CRQ with a transport event (0xFF) to
934                  * tell this client what has happened to the transport.  This
935                  * will be handled in ibmvscsi_handle_crq()
936                  */
937                 if (rc == H_CLOSED) {
938                         dev_warn(hostdata->dev, "send warning. "
939                                  "Receive queue closed, will retry.\n");
940                         goto send_busy;
941                 }
942                 dev_err(hostdata->dev, "send error %d\n", rc);
943                 if (srp_req)
944                         atomic_inc(&hostdata->request_limit);
945                 goto send_error;
946         }
947 
948         return 0;
949 
950  send_busy:
951         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
952 
953         free_event_struct(&hostdata->pool, evt_struct);
954         if (srp_req && request_status != -1)
955                 atomic_inc(&hostdata->request_limit);
956         return SCSI_MLQUEUE_HOST_BUSY;
957 
958  send_error:
959         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
960 
961         if (evt_struct->cmnd != NULL) {
962                 evt_struct->cmnd->result = DID_ERROR << 16;
963                 evt_struct->cmnd_done(evt_struct->cmnd);
964         } else if (evt_struct->done)
965                 evt_struct->done(evt_struct);
966 
967         free_event_struct(&hostdata->pool, evt_struct);
968         return 0;
969 }
970 
971 /**
972  * handle_cmd_rsp: -  Handle responses from commands
973  * @evt_struct: srp_event_struct to be handled
974  *
975  * Used as a callback by when sending scsi cmds.
976  * Gets called by ibmvscsi_handle_crq()
977 */
978 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
979 {
980         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
981         struct scsi_cmnd *cmnd = evt_struct->cmnd;
982 
983         if (unlikely(rsp->opcode != SRP_RSP)) {
984                 if (printk_ratelimit())
985                         dev_warn(evt_struct->hostdata->dev,
986                                  "bad SRP RSP type %d\n", rsp->opcode);
987         }
988         
989         if (cmnd) {
990                 cmnd->result |= rsp->status;
991                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
992                         memcpy(cmnd->sense_buffer,
993                                rsp->data,
994                                be32_to_cpu(rsp->sense_data_len));
995                 unmap_cmd_data(&evt_struct->iu.srp.cmd, 
996                                evt_struct, 
997                                evt_struct->hostdata->dev);
998 
999                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
1000                         scsi_set_resid(cmnd,
1001                                        be32_to_cpu(rsp->data_out_res_cnt));
1002                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
1003                         scsi_set_resid(cmnd, be32_to_cpu(rsp->data_in_res_cnt));
1004         }
1005 
1006         if (evt_struct->cmnd_done)
1007                 evt_struct->cmnd_done(cmnd);
1008 }
1009 
1010 /**
1011  * lun_from_dev: - Returns the lun of the scsi device
1012  * @dev:        struct scsi_device
1013  *
1014 */
1015 static inline u16 lun_from_dev(struct scsi_device *dev)
1016 {
1017         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
1018 }
1019 
1020 /**
1021  * ibmvscsi_queue: - The queuecommand function of the scsi template 
1022  * @cmd:        struct scsi_cmnd to be executed
1023  * @done:       Callback function to be called when cmd is completed
1024 */
1025 static int ibmvscsi_queuecommand_lck(struct scsi_cmnd *cmnd,
1026                                  void (*done) (struct scsi_cmnd *))
1027 {
1028         struct srp_cmd *srp_cmd;
1029         struct srp_event_struct *evt_struct;
1030         struct srp_indirect_buf *indirect;
1031         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
1032         u16 lun = lun_from_dev(cmnd->device);
1033         u8 out_fmt, in_fmt;
1034 
1035         cmnd->result = (DID_OK << 16);
1036         evt_struct = get_event_struct(&hostdata->pool);
1037         if (!evt_struct)
1038                 return SCSI_MLQUEUE_HOST_BUSY;
1039 
1040         /* Set up the actual SRP IU */
1041         srp_cmd = &evt_struct->iu.srp.cmd;
1042         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
1043         srp_cmd->opcode = SRP_CMD;
1044         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
1045         srp_cmd->lun = cpu_to_be64(((u64)lun) << 48);
1046 
1047         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
1048                 if (!firmware_has_feature(FW_FEATURE_CMO))
1049                         sdev_printk(KERN_ERR, cmnd->device,
1050                                     "couldn't convert cmd to srp_cmd\n");
1051                 free_event_struct(&hostdata->pool, evt_struct);
1052                 return SCSI_MLQUEUE_HOST_BUSY;
1053         }
1054 
1055         init_event_struct(evt_struct,
1056                           handle_cmd_rsp,
1057                           VIOSRP_SRP_FORMAT,
1058                           cmnd->request->timeout/HZ);
1059 
1060         evt_struct->cmnd = cmnd;
1061         evt_struct->cmnd_done = done;
1062 
1063         /* Fix up dma address of the buffer itself */
1064         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
1065         out_fmt = srp_cmd->buf_fmt >> 4;
1066         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
1067         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
1068              out_fmt == SRP_DATA_DESC_INDIRECT) &&
1069             indirect->table_desc.va == 0) {
1070                 indirect->table_desc.va =
1071                         cpu_to_be64(be64_to_cpu(evt_struct->crq.IU_data_ptr) +
1072                         offsetof(struct srp_cmd, add_data) +
1073                         offsetof(struct srp_indirect_buf, desc_list));
1074         }
1075 
1076         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
1077 }
1078 
1079 static DEF_SCSI_QCMD(ibmvscsi_queuecommand)
1080 
1081 /* ------------------------------------------------------------
1082  * Routines for driver initialization
1083  */
1084 
1085 /**
1086  * map_persist_bufs: - Pre-map persistent data for adapter logins
1087  * @hostdata:   ibmvscsi_host_data of host
1088  *
1089  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
1090  * Return 1 on error, 0 on success.
1091  */
1092 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
1093 {
1094 
1095         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
1096                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1097 
1098         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
1099                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
1100                 return 1;
1101         }
1102 
1103         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
1104                                                      &hostdata->madapter_info,
1105                                                      sizeof(hostdata->madapter_info),
1106                                                      DMA_BIDIRECTIONAL);
1107         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
1108                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
1109                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
1110                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1111                 return 1;
1112         }
1113 
1114         return 0;
1115 }
1116 
1117 /**
1118  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
1119  * @hostdata:   ibmvscsi_host_data of host
1120  *
1121  * Unmap the capabilities and adapter info DMA buffers
1122  */
1123 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
1124 {
1125         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
1126                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1127 
1128         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
1129                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
1130 }
1131 
1132 /**
1133  * login_rsp: - Handle response to SRP login request
1134  * @evt_struct: srp_event_struct with the response
1135  *
1136  * Used as a "done" callback by when sending srp_login. Gets called
1137  * by ibmvscsi_handle_crq()
1138 */
1139 static void login_rsp(struct srp_event_struct *evt_struct)
1140 {
1141         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1142         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
1143         case SRP_LOGIN_RSP:     /* it worked! */
1144                 break;
1145         case SRP_LOGIN_REJ:     /* refused! */
1146                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
1147                          evt_struct->xfer_iu->srp.login_rej.reason);
1148                 /* Login failed.  */
1149                 atomic_set(&hostdata->request_limit, -1);
1150                 return;
1151         default:
1152                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
1153                         evt_struct->xfer_iu->srp.login_rsp.opcode);
1154                 /* Login failed.  */
1155                 atomic_set(&hostdata->request_limit, -1);
1156                 return;
1157         }
1158 
1159         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
1160         hostdata->client_migrated = 0;
1161 
1162         /* Now we know what the real request-limit is.
1163          * This value is set rather than added to request_limit because
1164          * request_limit could have been set to -1 by this client.
1165          */
1166         atomic_set(&hostdata->request_limit,
1167                    be32_to_cpu(evt_struct->xfer_iu->srp.login_rsp.req_lim_delta));
1168 
1169         /* If we had any pending I/Os, kick them */
1170         scsi_unblock_requests(hostdata->host);
1171 }
1172 
1173 /**
1174  * send_srp_login: - Sends the srp login
1175  * @hostdata:   ibmvscsi_host_data of host
1176  *
1177  * Returns zero if successful.
1178 */
1179 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
1180 {
1181         int rc;
1182         unsigned long flags;
1183         struct srp_login_req *login;
1184         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
1185 
1186         BUG_ON(!evt_struct);
1187         init_event_struct(evt_struct, login_rsp,
1188                           VIOSRP_SRP_FORMAT, login_timeout);
1189 
1190         login = &evt_struct->iu.srp.login_req;
1191         memset(login, 0, sizeof(*login));
1192         login->opcode = SRP_LOGIN_REQ;
1193         login->req_it_iu_len = cpu_to_be32(sizeof(union srp_iu));
1194         login->req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
1195                                          SRP_BUF_FORMAT_INDIRECT);
1196 
1197         spin_lock_irqsave(hostdata->host->host_lock, flags);
1198         /* Start out with a request limit of 0, since this is negotiated in
1199          * the login request we are just sending and login requests always
1200          * get sent by the driver regardless of request_limit.
1201          */
1202         atomic_set(&hostdata->request_limit, 0);
1203 
1204         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
1205         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1206         dev_info(hostdata->dev, "sent SRP login\n");
1207         return rc;
1208 };
1209 
1210 /**
1211  * capabilities_rsp: - Handle response to MAD adapter capabilities request
1212  * @evt_struct: srp_event_struct with the response
1213  *
1214  * Used as a "done" callback by when sending adapter_info.
1215  */
1216 static void capabilities_rsp(struct srp_event_struct *evt_struct)
1217 {
1218         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1219 
1220         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
1221                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
1222                         evt_struct->xfer_iu->mad.capabilities.common.status);
1223         } else {
1224                 if (hostdata->caps.migration.common.server_support !=
1225                     cpu_to_be16(SERVER_SUPPORTS_CAP))
1226                         dev_info(hostdata->dev, "Partition migration not supported\n");
1227 
1228                 if (client_reserve) {
1229                         if (hostdata->caps.reserve.common.server_support ==
1230                             cpu_to_be16(SERVER_SUPPORTS_CAP))
1231                                 dev_info(hostdata->dev, "Client reserve enabled\n");
1232                         else
1233                                 dev_info(hostdata->dev, "Client reserve not supported\n");
1234                 }
1235         }
1236 
1237         send_srp_login(hostdata);
1238 }
1239 
1240 /**
1241  * send_mad_capabilities: - Sends the mad capabilities request
1242  *      and stores the result so it can be retrieved with
1243  * @hostdata:   ibmvscsi_host_data of host
1244  */
1245 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
1246 {
1247         struct viosrp_capabilities *req;
1248         struct srp_event_struct *evt_struct;
1249         unsigned long flags;
1250         struct device_node *of_node = hostdata->dev->of_node;
1251         const char *location;
1252 
1253         evt_struct = get_event_struct(&hostdata->pool);
1254         BUG_ON(!evt_struct);
1255 
1256         init_event_struct(evt_struct, capabilities_rsp,
1257                           VIOSRP_MAD_FORMAT, info_timeout);
1258 
1259         req = &evt_struct->iu.mad.capabilities;
1260         memset(req, 0, sizeof(*req));
1261 
1262         hostdata->caps.flags = cpu_to_be32(CAP_LIST_SUPPORTED);
1263         if (hostdata->client_migrated)
1264                 hostdata->caps.flags |= cpu_to_be32(CLIENT_MIGRATED);
1265 
1266         strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
1267                 sizeof(hostdata->caps.name));
1268         hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
1269 
1270         location = of_get_property(of_node, "ibm,loc-code", NULL);
1271         location = location ? location : dev_name(hostdata->dev);
1272         strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
1273         hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
1274 
1275         req->common.type = cpu_to_be32(VIOSRP_CAPABILITIES_TYPE);
1276         req->buffer = cpu_to_be64(hostdata->caps_addr);
1277 
1278         hostdata->caps.migration.common.cap_type =
1279                                 cpu_to_be32(MIGRATION_CAPABILITIES);
1280         hostdata->caps.migration.common.length =
1281                                 cpu_to_be16(sizeof(hostdata->caps.migration));
1282         hostdata->caps.migration.common.server_support =
1283                                 cpu_to_be16(SERVER_SUPPORTS_CAP);
1284         hostdata->caps.migration.ecl = cpu_to_be32(1);
1285 
1286         if (client_reserve) {
1287                 hostdata->caps.reserve.common.cap_type =
1288                                         cpu_to_be32(RESERVATION_CAPABILITIES);
1289                 hostdata->caps.reserve.common.length =
1290                                 cpu_to_be16(sizeof(hostdata->caps.reserve));
1291                 hostdata->caps.reserve.common.server_support =
1292                                 cpu_to_be16(SERVER_SUPPORTS_CAP);
1293                 hostdata->caps.reserve.type =
1294                                 cpu_to_be32(CLIENT_RESERVE_SCSI_2);
1295                 req->common.length =
1296                                 cpu_to_be16(sizeof(hostdata->caps));
1297         } else
1298                 req->common.length = cpu_to_be16(sizeof(hostdata->caps) -
1299                                                 sizeof(hostdata->caps.reserve));
1300 
1301         spin_lock_irqsave(hostdata->host->host_lock, flags);
1302         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1303                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
1304         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1305 };
1306 
1307 /**
1308  * fast_fail_rsp: - Handle response to MAD enable fast fail
1309  * @evt_struct: srp_event_struct with the response
1310  *
1311  * Used as a "done" callback by when sending enable fast fail. Gets called
1312  * by ibmvscsi_handle_crq()
1313  */
1314 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
1315 {
1316         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1317         u16 status = be16_to_cpu(evt_struct->xfer_iu->mad.fast_fail.common.status);
1318 
1319         if (status == VIOSRP_MAD_NOT_SUPPORTED)
1320                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
1321         else if (status == VIOSRP_MAD_FAILED)
1322                 dev_err(hostdata->dev, "fast_fail request failed\n");
1323         else if (status != VIOSRP_MAD_SUCCESS)
1324                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
1325 
1326         send_mad_capabilities(hostdata);
1327 }
1328 
1329 /**
1330  * init_host - Start host initialization
1331  * @hostdata:   ibmvscsi_host_data of host
1332  *
1333  * Returns zero if successful.
1334  */
1335 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1336 {
1337         int rc;
1338         unsigned long flags;
1339         struct viosrp_fast_fail *fast_fail_mad;
1340         struct srp_event_struct *evt_struct;
1341 
1342         if (!fast_fail) {
1343                 send_mad_capabilities(hostdata);
1344                 return 0;
1345         }
1346 
1347         evt_struct = get_event_struct(&hostdata->pool);
1348         BUG_ON(!evt_struct);
1349 
1350         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1351 
1352         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1353         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1354         fast_fail_mad->common.type = cpu_to_be32(VIOSRP_ENABLE_FAST_FAIL);
1355         fast_fail_mad->common.length = cpu_to_be16(sizeof(*fast_fail_mad));
1356 
1357         spin_lock_irqsave(hostdata->host->host_lock, flags);
1358         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1359         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1360         return rc;
1361 }
1362 
1363 /**
1364  * adapter_info_rsp: - Handle response to MAD adapter info request
1365  * @evt_struct: srp_event_struct with the response
1366  *
1367  * Used as a "done" callback by when sending adapter_info. Gets called
1368  * by ibmvscsi_handle_crq()
1369 */
1370 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1371 {
1372         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1373 
1374         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1375                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1376                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1377         } else {
1378                 dev_info(hostdata->dev, "host srp version: %s, "
1379                          "host partition %s (%d), OS %d, max io %u\n",
1380                          hostdata->madapter_info.srp_version,
1381                          hostdata->madapter_info.partition_name,
1382                          be32_to_cpu(hostdata->madapter_info.partition_number),
1383                          be32_to_cpu(hostdata->madapter_info.os_type),
1384                          be32_to_cpu(hostdata->madapter_info.port_max_txu[0]));
1385                 
1386                 if (hostdata->madapter_info.port_max_txu[0]) 
1387                         hostdata->host->max_sectors = 
1388                                 be32_to_cpu(hostdata->madapter_info.port_max_txu[0]) >> 9;
1389                 
1390                 if (be32_to_cpu(hostdata->madapter_info.os_type) == 3 &&
1391                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1392                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1393                                 hostdata->madapter_info.srp_version);
1394                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1395                                 MAX_INDIRECT_BUFS);
1396                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1397                 }
1398 
1399                 if (be32_to_cpu(hostdata->madapter_info.os_type) == 3) {
1400                         enable_fast_fail(hostdata);
1401                         return;
1402                 }
1403         }
1404 
1405         send_srp_login(hostdata);
1406 }
1407 
1408 /**
1409  * send_mad_adapter_info: - Sends the mad adapter info request
1410  *      and stores the result so it can be retrieved with
1411  *      sysfs.  We COULD consider causing a failure if the
1412  *      returned SRP version doesn't match ours.
1413  * @hostdata:   ibmvscsi_host_data of host
1414  * 
1415  * Returns zero if successful.
1416 */
1417 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1418 {
1419         struct viosrp_adapter_info *req;
1420         struct srp_event_struct *evt_struct;
1421         unsigned long flags;
1422 
1423         evt_struct = get_event_struct(&hostdata->pool);
1424         BUG_ON(!evt_struct);
1425 
1426         init_event_struct(evt_struct,
1427                           adapter_info_rsp,
1428                           VIOSRP_MAD_FORMAT,
1429                           info_timeout);
1430         
1431         req = &evt_struct->iu.mad.adapter_info;
1432         memset(req, 0x00, sizeof(*req));
1433         
1434         req->common.type = cpu_to_be32(VIOSRP_ADAPTER_INFO_TYPE);
1435         req->common.length = cpu_to_be16(sizeof(hostdata->madapter_info));
1436         req->buffer = cpu_to_be64(hostdata->adapter_info_addr);
1437 
1438         spin_lock_irqsave(hostdata->host->host_lock, flags);
1439         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1440                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1441         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1442 };
1443 
1444 /**
1445  * init_adapter: Start virtual adapter initialization sequence
1446  *
1447  */
1448 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1449 {
1450         send_mad_adapter_info(hostdata);
1451 }
1452 
1453 /**
1454  * sync_completion: Signal that a synchronous command has completed
1455  * Note that after returning from this call, the evt_struct is freed.
1456  * the caller waiting on this completion shouldn't touch the evt_struct
1457  * again.
1458  */
1459 static void sync_completion(struct srp_event_struct *evt_struct)
1460 {
1461         /* copy the response back */
1462         if (evt_struct->sync_srp)
1463                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1464         
1465         complete(&evt_struct->comp);
1466 }
1467 
1468 /**
1469  * ibmvscsi_abort: Abort a command...from scsi host template
1470  * send this over to the server and wait synchronously for the response
1471  */
1472 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1473 {
1474         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1475         struct srp_tsk_mgmt *tsk_mgmt;
1476         struct srp_event_struct *evt;
1477         struct srp_event_struct *tmp_evt, *found_evt;
1478         union viosrp_iu srp_rsp;
1479         int rsp_rc;
1480         unsigned long flags;
1481         u16 lun = lun_from_dev(cmd->device);
1482         unsigned long wait_switch = 0;
1483 
1484         /* First, find this command in our sent list so we can figure
1485          * out the correct tag
1486          */
1487         spin_lock_irqsave(hostdata->host->host_lock, flags);
1488         wait_switch = jiffies + (init_timeout * HZ);
1489         do {
1490                 found_evt = NULL;
1491                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1492                         if (tmp_evt->cmnd == cmd) {
1493                                 found_evt = tmp_evt;
1494                                 break;
1495                         }
1496                 }
1497 
1498                 if (!found_evt) {
1499                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1500                         return SUCCESS;
1501                 }
1502 
1503                 evt = get_event_struct(&hostdata->pool);
1504                 if (evt == NULL) {
1505                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1506                         sdev_printk(KERN_ERR, cmd->device,
1507                                 "failed to allocate abort event\n");
1508                         return FAILED;
1509                 }
1510         
1511                 init_event_struct(evt,
1512                                   sync_completion,
1513                                   VIOSRP_SRP_FORMAT,
1514                                   abort_timeout);
1515 
1516                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1517         
1518                 /* Set up an abort SRP command */
1519                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1520                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1521                 tsk_mgmt->lun = cpu_to_be64(((u64) lun) << 48);
1522                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1523                 tsk_mgmt->task_tag = (u64) found_evt;
1524 
1525                 evt->sync_srp = &srp_rsp;
1526 
1527                 init_completion(&evt->comp);
1528                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1529 
1530                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1531                         break;
1532 
1533                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1534                 msleep(10);
1535                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1536         } while (time_before(jiffies, wait_switch));
1537 
1538         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1539 
1540         if (rsp_rc != 0) {
1541                 sdev_printk(KERN_ERR, cmd->device,
1542                             "failed to send abort() event. rc=%d\n", rsp_rc);
1543                 return FAILED;
1544         }
1545 
1546         sdev_printk(KERN_INFO, cmd->device,
1547                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1548                     (((u64) lun) << 48), (u64) found_evt);
1549 
1550         wait_for_completion(&evt->comp);
1551 
1552         /* make sure we got a good response */
1553         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1554                 if (printk_ratelimit())
1555                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1556                                     srp_rsp.srp.rsp.opcode);
1557                 return FAILED;
1558         }
1559 
1560         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1561                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1562         else
1563                 rsp_rc = srp_rsp.srp.rsp.status;
1564 
1565         if (rsp_rc) {
1566                 if (printk_ratelimit())
1567                         sdev_printk(KERN_WARNING, cmd->device,
1568                                     "abort code %d for task tag 0x%llx\n",
1569                                     rsp_rc, tsk_mgmt->task_tag);
1570                 return FAILED;
1571         }
1572 
1573         /* Because we dropped the spinlock above, it's possible
1574          * The event is no longer in our list.  Make sure it didn't
1575          * complete while we were aborting
1576          */
1577         spin_lock_irqsave(hostdata->host->host_lock, flags);
1578         found_evt = NULL;
1579         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1580                 if (tmp_evt->cmnd == cmd) {
1581                         found_evt = tmp_evt;
1582                         break;
1583                 }
1584         }
1585 
1586         if (found_evt == NULL) {
1587                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1588                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1589                             tsk_mgmt->task_tag);
1590                 return SUCCESS;
1591         }
1592 
1593         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1594                     tsk_mgmt->task_tag);
1595 
1596         cmd->result = (DID_ABORT << 16);
1597         list_del(&found_evt->list);
1598         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1599                        found_evt->hostdata->dev);
1600         free_event_struct(&found_evt->hostdata->pool, found_evt);
1601         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1602         atomic_inc(&hostdata->request_limit);
1603         return SUCCESS;
1604 }
1605 
1606 /**
1607  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host 
1608  * template send this over to the server and wait synchronously for the 
1609  * response
1610  */
1611 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1612 {
1613         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1614         struct srp_tsk_mgmt *tsk_mgmt;
1615         struct srp_event_struct *evt;
1616         struct srp_event_struct *tmp_evt, *pos;
1617         union viosrp_iu srp_rsp;
1618         int rsp_rc;
1619         unsigned long flags;
1620         u16 lun = lun_from_dev(cmd->device);
1621         unsigned long wait_switch = 0;
1622 
1623         spin_lock_irqsave(hostdata->host->host_lock, flags);
1624         wait_switch = jiffies + (init_timeout * HZ);
1625         do {
1626                 evt = get_event_struct(&hostdata->pool);
1627                 if (evt == NULL) {
1628                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1629                         sdev_printk(KERN_ERR, cmd->device,
1630                                 "failed to allocate reset event\n");
1631                         return FAILED;
1632                 }
1633         
1634                 init_event_struct(evt,
1635                                   sync_completion,
1636                                   VIOSRP_SRP_FORMAT,
1637                                   reset_timeout);
1638 
1639                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1640 
1641                 /* Set up a lun reset SRP command */
1642                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1643                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1644                 tsk_mgmt->lun = cpu_to_be64(((u64) lun) << 48);
1645                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1646 
1647                 evt->sync_srp = &srp_rsp;
1648 
1649                 init_completion(&evt->comp);
1650                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1651 
1652                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1653                         break;
1654 
1655                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1656                 msleep(10);
1657                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1658         } while (time_before(jiffies, wait_switch));
1659 
1660         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1661 
1662         if (rsp_rc != 0) {
1663                 sdev_printk(KERN_ERR, cmd->device,
1664                             "failed to send reset event. rc=%d\n", rsp_rc);
1665                 return FAILED;
1666         }
1667 
1668         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1669                     (((u64) lun) << 48));
1670 
1671         wait_for_completion(&evt->comp);
1672 
1673         /* make sure we got a good response */
1674         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1675                 if (printk_ratelimit())
1676                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1677                                     srp_rsp.srp.rsp.opcode);
1678                 return FAILED;
1679         }
1680 
1681         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1682                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1683         else
1684                 rsp_rc = srp_rsp.srp.rsp.status;
1685 
1686         if (rsp_rc) {
1687                 if (printk_ratelimit())
1688                         sdev_printk(KERN_WARNING, cmd->device,
1689                                     "reset code %d for task tag 0x%llx\n",
1690                                     rsp_rc, tsk_mgmt->task_tag);
1691                 return FAILED;
1692         }
1693 
1694         /* We need to find all commands for this LUN that have not yet been
1695          * responded to, and fail them with DID_RESET
1696          */
1697         spin_lock_irqsave(hostdata->host->host_lock, flags);
1698         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1699                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1700                         if (tmp_evt->cmnd)
1701                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1702                         list_del(&tmp_evt->list);
1703                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1704                                        tmp_evt->hostdata->dev);
1705                         free_event_struct(&tmp_evt->hostdata->pool,
1706                                                    tmp_evt);
1707                         atomic_inc(&hostdata->request_limit);
1708                         if (tmp_evt->cmnd_done)
1709                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1710                         else if (tmp_evt->done)
1711                                 tmp_evt->done(tmp_evt);
1712                 }
1713         }
1714         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1715         return SUCCESS;
1716 }
1717 
1718 /**
1719  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1720  * @cmd:        struct scsi_cmnd having problems
1721 */
1722 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1723 {
1724         unsigned long wait_switch = 0;
1725         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1726 
1727         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1728 
1729         ibmvscsi_reset_host(hostdata);
1730 
1731         for (wait_switch = jiffies + (init_timeout * HZ);
1732              time_before(jiffies, wait_switch) &&
1733                      atomic_read(&hostdata->request_limit) < 2;) {
1734 
1735                 msleep(10);
1736         }
1737 
1738         if (atomic_read(&hostdata->request_limit) <= 0)
1739                 return FAILED;
1740 
1741         return SUCCESS;
1742 }
1743 
1744 /**
1745  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1746  * @crq:        Command/Response queue
1747  * @hostdata:   ibmvscsi_host_data of host
1748  *
1749 */
1750 static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1751                                 struct ibmvscsi_host_data *hostdata)
1752 {
1753         long rc;
1754         unsigned long flags;
1755         /* The hypervisor copies our tag value here so no byteswapping */
1756         struct srp_event_struct *evt_struct =
1757                         (__force struct srp_event_struct *)crq->IU_data_ptr;
1758         switch (crq->valid) {
1759         case 0xC0:              /* initialization */
1760                 switch (crq->format) {
1761                 case 0x01:      /* Initialization message */
1762                         dev_info(hostdata->dev, "partner initialized\n");
1763                         /* Send back a response */
1764                         rc = ibmvscsi_send_crq(hostdata, 0xC002000000000000LL, 0);
1765                         if (rc == 0) {
1766                                 /* Now login */
1767                                 init_adapter(hostdata);
1768                         } else {
1769                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1770                         }
1771 
1772                         break;
1773                 case 0x02:      /* Initialization response */
1774                         dev_info(hostdata->dev, "partner initialization complete\n");
1775 
1776                         /* Now login */
1777                         init_adapter(hostdata);
1778                         break;
1779                 default:
1780                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1781                 }
1782                 return;
1783         case 0xFF:      /* Hypervisor telling us the connection is closed */
1784                 scsi_block_requests(hostdata->host);
1785                 atomic_set(&hostdata->request_limit, 0);
1786                 if (crq->format == 0x06) {
1787                         /* We need to re-setup the interpartition connection */
1788                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1789                         hostdata->client_migrated = 1;
1790                         hostdata->reenable_crq = 1;
1791                         purge_requests(hostdata, DID_REQUEUE);
1792                         wake_up(&hostdata->work_wait_q);
1793                 } else {
1794                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1795                                 crq->format);
1796                         ibmvscsi_reset_host(hostdata);
1797                 }
1798                 return;
1799         case 0x80:              /* real payload */
1800                 break;
1801         default:
1802                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1803                         crq->valid);
1804                 return;
1805         }
1806 
1807         /* The only kind of payload CRQs we should get are responses to
1808          * things we send. Make sure this response is to something we
1809          * actually sent
1810          */
1811         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1812                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1813                        evt_struct);
1814                 return;
1815         }
1816 
1817         if (atomic_read(&evt_struct->free)) {
1818                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1819                         evt_struct);
1820                 return;
1821         }
1822 
1823         if (crq->format == VIOSRP_SRP_FORMAT)
1824                 atomic_add(be32_to_cpu(evt_struct->xfer_iu->srp.rsp.req_lim_delta),
1825                            &hostdata->request_limit);
1826 
1827         del_timer(&evt_struct->timer);
1828 
1829         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1830                 evt_struct->cmnd->result = DID_ERROR << 16;
1831         if (evt_struct->done)
1832                 evt_struct->done(evt_struct);
1833         else
1834                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1835 
1836         /*
1837          * Lock the host_lock before messing with these structures, since we
1838          * are running in a task context
1839          */
1840         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1841         list_del(&evt_struct->list);
1842         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1843         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1844 }
1845 
1846 /**
1847  * ibmvscsi_get_host_config: Send the command to the server to get host
1848  * configuration data.  The data is opaque to us.
1849  */
1850 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1851                                    unsigned char *buffer, int length)
1852 {
1853         struct viosrp_host_config *host_config;
1854         struct srp_event_struct *evt_struct;
1855         unsigned long flags;
1856         dma_addr_t addr;
1857         int rc;
1858 
1859         evt_struct = get_event_struct(&hostdata->pool);
1860         if (!evt_struct) {
1861                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1862                 return -1;
1863         }
1864 
1865         init_event_struct(evt_struct,
1866                           sync_completion,
1867                           VIOSRP_MAD_FORMAT,
1868                           info_timeout);
1869 
1870         host_config = &evt_struct->iu.mad.host_config;
1871 
1872         /* The transport length field is only 16-bit */
1873         length = min(0xffff, length);
1874 
1875         /* Set up a lun reset SRP command */
1876         memset(host_config, 0x00, sizeof(*host_config));
1877         host_config->common.type = cpu_to_be32(VIOSRP_HOST_CONFIG_TYPE);
1878         host_config->common.length = cpu_to_be16(length);
1879         addr = dma_map_single(hostdata->dev, buffer, length, DMA_BIDIRECTIONAL);
1880 
1881         if (dma_mapping_error(hostdata->dev, addr)) {
1882                 if (!firmware_has_feature(FW_FEATURE_CMO))
1883                         dev_err(hostdata->dev,
1884                                 "dma_mapping error getting host config\n");
1885                 free_event_struct(&hostdata->pool, evt_struct);
1886                 return -1;
1887         }
1888 
1889         host_config->buffer = cpu_to_be64(addr);
1890 
1891         init_completion(&evt_struct->comp);
1892         spin_lock_irqsave(hostdata->host->host_lock, flags);
1893         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1894         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1895         if (rc == 0)
1896                 wait_for_completion(&evt_struct->comp);
1897         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1898 
1899         return rc;
1900 }
1901 
1902 /**
1903  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1904  * @sdev:       struct scsi_device device to configure
1905  *
1906  * Enable allow_restart for a device if it is a disk.  Adjust the
1907  * queue_depth here also as is required by the documentation for
1908  * struct scsi_host_template.
1909  */
1910 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1911 {
1912         struct Scsi_Host *shost = sdev->host;
1913         unsigned long lock_flags = 0;
1914 
1915         spin_lock_irqsave(shost->host_lock, lock_flags);
1916         if (sdev->type == TYPE_DISK) {
1917                 sdev->allow_restart = 1;
1918                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1919         }
1920         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1921         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1922         return 0;
1923 }
1924 
1925 /**
1926  * ibmvscsi_change_queue_depth - Change the device's queue depth
1927  * @sdev:       scsi device struct
1928  * @qdepth:     depth to set
1929  * @reason:     calling context
1930  *
1931  * Return value:
1932  *      actual depth set
1933  **/
1934 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth,
1935                                        int reason)
1936 {
1937         if (reason != SCSI_QDEPTH_DEFAULT)
1938                 return -EOPNOTSUPP;
1939 
1940         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1941                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1942 
1943         scsi_adjust_queue_depth(sdev, 0, qdepth);
1944         return sdev->queue_depth;
1945 }
1946 
1947 /* ------------------------------------------------------------
1948  * sysfs attributes
1949  */
1950 static ssize_t show_host_vhost_loc(struct device *dev,
1951                                    struct device_attribute *attr, char *buf)
1952 {
1953         struct Scsi_Host *shost = class_to_shost(dev);
1954         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1955         int len;
1956 
1957         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1958                        hostdata->caps.loc);
1959         return len;
1960 }
1961 
1962 static struct device_attribute ibmvscsi_host_vhost_loc = {
1963         .attr = {
1964                  .name = "vhost_loc",
1965                  .mode = S_IRUGO,
1966                  },
1967         .show = show_host_vhost_loc,
1968 };
1969 
1970 static ssize_t show_host_vhost_name(struct device *dev,
1971                                     struct device_attribute *attr, char *buf)
1972 {
1973         struct Scsi_Host *shost = class_to_shost(dev);
1974         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1975         int len;
1976 
1977         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1978                        hostdata->caps.name);
1979         return len;
1980 }
1981 
1982 static struct device_attribute ibmvscsi_host_vhost_name = {
1983         .attr = {
1984                  .name = "vhost_name",
1985                  .mode = S_IRUGO,
1986                  },
1987         .show = show_host_vhost_name,
1988 };
1989 
1990 static ssize_t show_host_srp_version(struct device *dev,
1991                                      struct device_attribute *attr, char *buf)
1992 {
1993         struct Scsi_Host *shost = class_to_shost(dev);
1994         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1995         int len;
1996 
1997         len = snprintf(buf, PAGE_SIZE, "%s\n",
1998                        hostdata->madapter_info.srp_version);
1999         return len;
2000 }
2001 
2002 static struct device_attribute ibmvscsi_host_srp_version = {
2003         .attr = {
2004                  .name = "srp_version",
2005                  .mode = S_IRUGO,
2006                  },
2007         .show = show_host_srp_version,
2008 };
2009 
2010 static ssize_t show_host_partition_name(struct device *dev,
2011                                         struct device_attribute *attr,
2012                                         char *buf)
2013 {
2014         struct Scsi_Host *shost = class_to_shost(dev);
2015         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2016         int len;
2017 
2018         len = snprintf(buf, PAGE_SIZE, "%s\n",
2019                        hostdata->madapter_info.partition_name);
2020         return len;
2021 }
2022 
2023 static struct device_attribute ibmvscsi_host_partition_name = {
2024         .attr = {
2025                  .name = "partition_name",
2026                  .mode = S_IRUGO,
2027                  },
2028         .show = show_host_partition_name,
2029 };
2030 
2031 static ssize_t show_host_partition_number(struct device *dev,
2032                                           struct device_attribute *attr,
2033                                           char *buf)
2034 {
2035         struct Scsi_Host *shost = class_to_shost(dev);
2036         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2037         int len;
2038 
2039         len = snprintf(buf, PAGE_SIZE, "%d\n",
2040                        hostdata->madapter_info.partition_number);
2041         return len;
2042 }
2043 
2044 static struct device_attribute ibmvscsi_host_partition_number = {
2045         .attr = {
2046                  .name = "partition_number",
2047                  .mode = S_IRUGO,
2048                  },
2049         .show = show_host_partition_number,
2050 };
2051 
2052 static ssize_t show_host_mad_version(struct device *dev,
2053                                      struct device_attribute *attr, char *buf)
2054 {
2055         struct Scsi_Host *shost = class_to_shost(dev);
2056         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2057         int len;
2058 
2059         len = snprintf(buf, PAGE_SIZE, "%d\n",
2060                        hostdata->madapter_info.mad_version);
2061         return len;
2062 }
2063 
2064 static struct device_attribute ibmvscsi_host_mad_version = {
2065         .attr = {
2066                  .name = "mad_version",
2067                  .mode = S_IRUGO,
2068                  },
2069         .show = show_host_mad_version,
2070 };
2071 
2072 static ssize_t show_host_os_type(struct device *dev,
2073                                  struct device_attribute *attr, char *buf)
2074 {
2075         struct Scsi_Host *shost = class_to_shost(dev);
2076         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2077         int len;
2078 
2079         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
2080         return len;
2081 }
2082 
2083 static struct device_attribute ibmvscsi_host_os_type = {
2084         .attr = {
2085                  .name = "os_type",
2086                  .mode = S_IRUGO,
2087                  },
2088         .show = show_host_os_type,
2089 };
2090 
2091 static ssize_t show_host_config(struct device *dev,
2092                                 struct device_attribute *attr, char *buf)
2093 {
2094         struct Scsi_Host *shost = class_to_shost(dev);
2095         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2096 
2097         /* returns null-terminated host config data */
2098         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
2099                 return strlen(buf);
2100         else
2101                 return 0;
2102 }
2103 
2104 static struct device_attribute ibmvscsi_host_config = {
2105         .attr = {
2106                  .name = "config",
2107                  .mode = S_IRUGO,
2108                  },
2109         .show = show_host_config,
2110 };
2111 
2112 static struct device_attribute *ibmvscsi_attrs[] = {
2113         &ibmvscsi_host_vhost_loc,
2114         &ibmvscsi_host_vhost_name,
2115         &ibmvscsi_host_srp_version,
2116         &ibmvscsi_host_partition_name,
2117         &ibmvscsi_host_partition_number,
2118         &ibmvscsi_host_mad_version,
2119         &ibmvscsi_host_os_type,
2120         &ibmvscsi_host_config,
2121         NULL
2122 };
2123 
2124 /* ------------------------------------------------------------
2125  * SCSI driver registration
2126  */
2127 static struct scsi_host_template driver_template = {
2128         .module = THIS_MODULE,
2129         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
2130         .proc_name = "ibmvscsi",
2131         .queuecommand = ibmvscsi_queuecommand,
2132         .eh_abort_handler = ibmvscsi_eh_abort_handler,
2133         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
2134         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
2135         .slave_configure = ibmvscsi_slave_configure,
2136         .change_queue_depth = ibmvscsi_change_queue_depth,
2137         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
2138         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
2139         .this_id = -1,
2140         .sg_tablesize = SG_ALL,
2141         .use_clustering = ENABLE_CLUSTERING,
2142         .shost_attrs = ibmvscsi_attrs,
2143 };
2144 
2145 /**
2146  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
2147  *
2148  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
2149  *
2150  * Return value:
2151  *      Number of bytes of IO data the driver will need to perform well.
2152  */
2153 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
2154 {
2155         /* iu_storage data allocated in initialize_event_pool */
2156         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
2157 
2158         /* add io space for sg data */
2159         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
2160                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
2161 
2162         return desired_io;
2163 }
2164 
2165 static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata)
2166 {
2167         int rc;
2168         char *action = "reset";
2169 
2170         if (hostdata->reset_crq) {
2171                 smp_rmb();
2172                 hostdata->reset_crq = 0;
2173 
2174                 rc = ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata);
2175                 if (!rc)
2176                         rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
2177                 vio_enable_interrupts(to_vio_dev(hostdata->dev));
2178         } else if (hostdata->reenable_crq) {
2179                 smp_rmb();
2180                 action = "enable";
2181                 rc = ibmvscsi_reenable_crq_queue(&hostdata->queue, hostdata);
2182                 hostdata->reenable_crq = 0;
2183                 if (!rc)
2184                         rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
2185         } else
2186                 return;
2187 
2188         if (rc) {
2189                 atomic_set(&hostdata->request_limit, -1);
2190                 dev_err(hostdata->dev, "error after %s\n", action);
2191         }
2192 
2193         scsi_unblock_requests(hostdata->host);
2194 }
2195 
2196 static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
2197 {
2198         if (kthread_should_stop())
2199                 return 1;
2200         else if (hostdata->reset_crq) {
2201                 smp_rmb();
2202                 return 1;
2203         } else if (hostdata->reenable_crq) {
2204                 smp_rmb();
2205                 return 1;
2206         }
2207 
2208         return 0;
2209 }
2210 
2211 static int ibmvscsi_work(void *data)
2212 {
2213         struct ibmvscsi_host_data *hostdata = data;
2214         int rc;
2215 
2216         set_user_nice(current, -20);
2217 
2218         while (1) {
2219                 rc = wait_event_interruptible(hostdata->work_wait_q,
2220                                               ibmvscsi_work_to_do(hostdata));
2221 
2222                 BUG_ON(rc);
2223 
2224                 if (kthread_should_stop())
2225                         break;
2226 
2227                 ibmvscsi_do_work(hostdata);
2228         }
2229 
2230         return 0;
2231 }
2232 
2233 /**
2234  * Called by bus code for each adapter
2235  */
2236 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
2237 {
2238         struct ibmvscsi_host_data *hostdata;
2239         struct Scsi_Host *host;
2240         struct device *dev = &vdev->dev;
2241         struct srp_rport_identifiers ids;
2242         struct srp_rport *rport;
2243         unsigned long wait_switch = 0;
2244         int rc;
2245 
2246         dev_set_drvdata(&vdev->dev, NULL);
2247 
2248         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
2249         if (!host) {
2250                 dev_err(&vdev->dev, "couldn't allocate host data\n");
2251                 goto scsi_host_alloc_failed;
2252         }
2253 
2254         host->transportt = ibmvscsi_transport_template;
2255         hostdata = shost_priv(host);
2256         memset(hostdata, 0x00, sizeof(*hostdata));
2257         INIT_LIST_HEAD(&hostdata->sent);
2258         init_waitqueue_head(&hostdata->work_wait_q);
2259         hostdata->host = host;
2260         hostdata->dev = dev;
2261         atomic_set(&hostdata->request_limit, -1);
2262         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
2263 
2264         if (map_persist_bufs(hostdata)) {
2265                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
2266                 goto persist_bufs_failed;
2267         }
2268 
2269         hostdata->work_thread = kthread_run(ibmvscsi_work, hostdata, "%s_%d",
2270                                             "ibmvscsi", host->host_no);
2271 
2272         if (IS_ERR(hostdata->work_thread)) {
2273                 dev_err(&vdev->dev, "couldn't initialize kthread. rc=%ld\n",
2274                         PTR_ERR(hostdata->work_thread));
2275                 goto init_crq_failed;
2276         }
2277 
2278         rc = ibmvscsi_init_crq_queue(&hostdata->queue, hostdata, max_events);
2279         if (rc != 0 && rc != H_RESOURCE) {
2280                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
2281                 goto kill_kthread;
2282         }
2283         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
2284                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
2285                 goto init_pool_failed;
2286         }
2287 
2288         host->max_lun = 8;
2289         host->max_id = max_id;
2290         host->max_channel = max_channel;
2291         host->max_cmd_len = 16;
2292 
2293         if (scsi_add_host(hostdata->host, hostdata->dev))
2294                 goto add_host_failed;
2295 
2296         /* we don't have a proper target_port_id so let's use the fake one */
2297         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
2298                sizeof(ids.port_id));
2299         ids.roles = SRP_RPORT_ROLE_TARGET;
2300         rport = srp_rport_add(host, &ids);
2301         if (IS_ERR(rport))
2302                 goto add_srp_port_failed;
2303 
2304         /* Try to send an initialization message.  Note that this is allowed
2305          * to fail if the other end is not acive.  In that case we don't
2306          * want to scan
2307          */
2308         if (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0) == 0
2309             || rc == H_RESOURCE) {
2310                 /*
2311                  * Wait around max init_timeout secs for the adapter to finish
2312                  * initializing. When we are done initializing, we will have a
2313                  * valid request_limit.  We don't want Linux scanning before
2314                  * we are ready.
2315                  */
2316                 for (wait_switch = jiffies + (init_timeout * HZ);
2317                      time_before(jiffies, wait_switch) &&
2318                      atomic_read(&hostdata->request_limit) < 2;) {
2319 
2320                         msleep(10);
2321                 }
2322 
2323                 /* if we now have a valid request_limit, initiate a scan */
2324                 if (atomic_read(&hostdata->request_limit) > 0)
2325                         scsi_scan_host(host);
2326         }
2327 
2328         dev_set_drvdata(&vdev->dev, hostdata);
2329         return 0;
2330 
2331       add_srp_port_failed:
2332         scsi_remove_host(hostdata->host);
2333       add_host_failed:
2334         release_event_pool(&hostdata->pool, hostdata);
2335       init_pool_failed:
2336         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata, max_events);
2337       kill_kthread:
2338       kthread_stop(hostdata->work_thread);
2339       init_crq_failed:
2340         unmap_persist_bufs(hostdata);
2341       persist_bufs_failed:
2342         scsi_host_put(host);
2343       scsi_host_alloc_failed:
2344         return -1;
2345 }
2346 
2347 static int ibmvscsi_remove(struct vio_dev *vdev)
2348 {
2349         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
2350         unmap_persist_bufs(hostdata);
2351         release_event_pool(&hostdata->pool, hostdata);
2352         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
2353                                         max_events);
2354 
2355         kthread_stop(hostdata->work_thread);
2356         srp_remove_host(hostdata->host);
2357         scsi_remove_host(hostdata->host);
2358         scsi_host_put(hostdata->host);
2359 
2360         return 0;
2361 }
2362 
2363 /**
2364  * ibmvscsi_resume: Resume from suspend
2365  * @dev:        device struct
2366  *
2367  * We may have lost an interrupt across suspend/resume, so kick the
2368  * interrupt handler
2369  */
2370 static int ibmvscsi_resume(struct device *dev)
2371 {
2372         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
2373         vio_disable_interrupts(to_vio_dev(hostdata->dev));
2374         tasklet_schedule(&hostdata->srp_task);
2375 
2376         return 0;
2377 }
2378 
2379 /**
2380  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we 
2381  * support.
2382  */
2383 static struct vio_device_id ibmvscsi_device_table[] = {
2384         {"vscsi", "IBM,v-scsi"},
2385         { "", "" }
2386 };
2387 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
2388 
2389 static struct dev_pm_ops ibmvscsi_pm_ops = {
2390         .resume = ibmvscsi_resume
2391 };
2392 
2393 static struct vio_driver ibmvscsi_driver = {
2394         .id_table = ibmvscsi_device_table,
2395         .probe = ibmvscsi_probe,
2396         .remove = ibmvscsi_remove,
2397         .get_desired_dma = ibmvscsi_get_desired_dma,
2398         .name = "ibmvscsi",
2399         .pm = &ibmvscsi_pm_ops,
2400 };
2401 
2402 static struct srp_function_template ibmvscsi_transport_functions = {
2403 };
2404 
2405 int __init ibmvscsi_module_init(void)
2406 {
2407         int ret;
2408 
2409         /* Ensure we have two requests to do error recovery */
2410         driver_template.can_queue = max_requests;
2411         max_events = max_requests + 2;
2412 
2413         if (!firmware_has_feature(FW_FEATURE_VIO))
2414                 return -ENODEV;
2415 
2416         ibmvscsi_transport_template =
2417                 srp_attach_transport(&ibmvscsi_transport_functions);
2418         if (!ibmvscsi_transport_template)
2419                 return -ENOMEM;
2420 
2421         ret = vio_register_driver(&ibmvscsi_driver);
2422         if (ret)
2423                 srp_release_transport(ibmvscsi_transport_template);
2424         return ret;
2425 }
2426 
2427 void __exit ibmvscsi_module_exit(void)
2428 {
2429         vio_unregister_driver(&ibmvscsi_driver);
2430         srp_release_transport(ibmvscsi_transport_template);
2431 }
2432 
2433 module_init(ibmvscsi_module_init);
2434 module_exit(ibmvscsi_module_exit);
2435 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us