Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
[linux-2.6-microblaze.git] / drivers / scsi / ibmvscsi / ibmvscsi.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* ------------------------------------------------------------
3  * ibmvscsi.c
4  * (C) Copyright IBM Corporation 1994, 2004
5  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
6  *          Santiago Leon (santil@us.ibm.com)
7  *          Dave Boutcher (sleddog@us.ibm.com)
8  *
9  * ------------------------------------------------------------
10  * Emulation of a SCSI host adapter for Virtual I/O devices
11  *
12  * This driver supports the SCSI adapter implemented by the IBM
13  * Power5 firmware.  That SCSI adapter is not a physical adapter,
14  * but allows Linux SCSI peripheral drivers to directly
15  * access devices in another logical partition on the physical system.
16  *
17  * The virtual adapter(s) are present in the open firmware device
18  * tree just like real adapters.
19  *
20  * One of the capabilities provided on these systems is the ability
21  * to DMA between partitions.  The architecture states that for VSCSI,
22  * the server side is allowed to DMA to and from the client.  The client
23  * is never trusted to DMA to or from the server directly.
24  *
25  * Messages are sent between partitions on a "Command/Response Queue" 
26  * (CRQ), which is just a buffer of 16 byte entries in the receiver's 
27  * Senders cannot access the buffer directly, but send messages by
28  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
29  * puts the message in the next 16 byte space in round-robin fashion,
30  * turns on the high order bit of the message (the valid bit), and 
31  * generates an interrupt to the receiver (if interrupts are turned on.) 
32  * The receiver just turns off the valid bit when they have copied out
33  * the message.
34  *
35  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
36  * (IU) (as defined in the T10 standard available at www.t10.org), gets 
37  * a DMA address for the message, and sends it to the server as the
38  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
39  * including doing any additional data transfers.  When it is done, it
40  * DMAs the SRP response back to the same address as the request came from,
41  * and sends a CRQ message back to inform the client that the request has
42  * completed.
43  *
44  * TODO: This is currently pretty tied to the IBM pSeries hypervisor
45  * interfaces.  It would be really nice to abstract this above an RDMA
46  * layer.
47  */
48
49 #include <linux/module.h>
50 #include <linux/moduleparam.h>
51 #include <linux/dma-mapping.h>
52 #include <linux/delay.h>
53 #include <linux/slab.h>
54 #include <linux/of.h>
55 #include <linux/pm.h>
56 #include <linux/kthread.h>
57 #include <asm/firmware.h>
58 #include <asm/vio.h>
59 #include <scsi/scsi.h>
60 #include <scsi/scsi_cmnd.h>
61 #include <scsi/scsi_host.h>
62 #include <scsi/scsi_device.h>
63 #include <scsi/scsi_transport_srp.h>
64 #include "ibmvscsi.h"
65
66 /* The values below are somewhat arbitrary default values, but 
67  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
68  * Note that there are 3 bits of channel value, 6 bits of id, and
69  * 5 bits of LUN.
70  */
71 static int max_id = 64;
72 static int max_channel = 3;
73 static int init_timeout = 300;
74 static int login_timeout = 60;
75 static int info_timeout = 30;
76 static int abort_timeout = 60;
77 static int reset_timeout = 60;
78 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
79 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
80 static int fast_fail = 1;
81 static int client_reserve = 1;
82 static char partition_name[96] = "UNKNOWN";
83 static unsigned int partition_number = -1;
84 static LIST_HEAD(ibmvscsi_head);
85 static DEFINE_SPINLOCK(ibmvscsi_driver_lock);
86
87 static struct scsi_transport_template *ibmvscsi_transport_template;
88
89 #define IBMVSCSI_VERSION "1.5.9"
90
91 MODULE_DESCRIPTION("IBM Virtual SCSI");
92 MODULE_AUTHOR("Dave Boutcher");
93 MODULE_LICENSE("GPL");
94 MODULE_VERSION(IBMVSCSI_VERSION);
95
96 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
97 MODULE_PARM_DESC(max_id, "Largest ID value for each channel [Default=64]");
98 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
99 MODULE_PARM_DESC(max_channel, "Largest channel value [Default=3]");
100 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
101 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
102 module_param_named(max_requests, max_requests, int, S_IRUGO);
103 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
104 module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
105 MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
106 module_param_named(client_reserve, client_reserve, int, S_IRUGO );
107 MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
108
109 static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
110                                 struct ibmvscsi_host_data *hostdata);
111
112 /* ------------------------------------------------------------
113  * Routines for managing the command/response queue
114  */
115 /**
116  * ibmvscsi_handle_event: - Interrupt handler for crq events
117  * @irq:        number of irq to handle, not used
118  * @dev_instance: ibmvscsi_host_data of host that received interrupt
119  *
120  * Disables interrupts and schedules srp_task
121  * Always returns IRQ_HANDLED
122  */
123 static irqreturn_t ibmvscsi_handle_event(int irq, void *dev_instance)
124 {
125         struct ibmvscsi_host_data *hostdata =
126             (struct ibmvscsi_host_data *)dev_instance;
127         vio_disable_interrupts(to_vio_dev(hostdata->dev));
128         tasklet_schedule(&hostdata->srp_task);
129         return IRQ_HANDLED;
130 }
131
132 /**
133  * ibmvscsi_release_crq_queue() - Deallocates data and unregisters CRQ
134  * @queue:              crq_queue to initialize and register
135  * @hostdata:           ibmvscsi_host_data of host
136  * @max_requests:       maximum requests (unused)
137  *
138  * Frees irq, deallocates a page for messages, unmaps dma, and unregisters
139  * the crq with the hypervisor.
140  */
141 static void ibmvscsi_release_crq_queue(struct crq_queue *queue,
142                                        struct ibmvscsi_host_data *hostdata,
143                                        int max_requests)
144 {
145         long rc = 0;
146         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
147         free_irq(vdev->irq, (void *)hostdata);
148         tasklet_kill(&hostdata->srp_task);
149         do {
150                 if (rc)
151                         msleep(100);
152                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
153         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
154         dma_unmap_single(hostdata->dev,
155                          queue->msg_token,
156                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
157         free_page((unsigned long)queue->msgs);
158 }
159
160 /**
161  * crq_queue_next_crq: - Returns the next entry in message queue
162  * @queue:      crq_queue to use
163  *
164  * Returns pointer to next entry in queue, or NULL if there are no new
165  * entried in the CRQ.
166  */
167 static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
168 {
169         struct viosrp_crq *crq;
170         unsigned long flags;
171
172         spin_lock_irqsave(&queue->lock, flags);
173         crq = &queue->msgs[queue->cur];
174         if (crq->valid != VIOSRP_CRQ_FREE) {
175                 if (++queue->cur == queue->size)
176                         queue->cur = 0;
177
178                 /* Ensure the read of the valid bit occurs before reading any
179                  * other bits of the CRQ entry
180                  */
181                 rmb();
182         } else
183                 crq = NULL;
184         spin_unlock_irqrestore(&queue->lock, flags);
185
186         return crq;
187 }
188
189 /**
190  * ibmvscsi_send_crq: - Send a CRQ
191  * @hostdata:   the adapter
192  * @word1:      the first 64 bits of the data
193  * @word2:      the second 64 bits of the data
194  */
195 static int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
196                              u64 word1, u64 word2)
197 {
198         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
199
200         /*
201          * Ensure the command buffer is flushed to memory before handing it
202          * over to the VIOS to prevent it from fetching any stale data.
203          */
204         mb();
205         return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
206 }
207
208 /**
209  * ibmvscsi_task: - Process srps asynchronously
210  * @data:       ibmvscsi_host_data of host
211  */
212 static void ibmvscsi_task(void *data)
213 {
214         struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data;
215         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
216         struct viosrp_crq *crq;
217         int done = 0;
218
219         while (!done) {
220                 /* Pull all the valid messages off the CRQ */
221                 while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
222                         ibmvscsi_handle_crq(crq, hostdata);
223                         crq->valid = VIOSRP_CRQ_FREE;
224                         wmb();
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 = VIOSRP_CRQ_FREE;
233                         wmb();
234                 } else {
235                         done = 1;
236                 }
237         }
238 }
239
240 static void gather_partition_info(void)
241 {
242         const char *ppartition_name;
243         const __be32 *p_number_ptr;
244
245         /* Retrieve information about this partition */
246         if (!of_root)
247                 return;
248
249         of_node_get(of_root);
250
251         ppartition_name = of_get_property(of_root, "ibm,partition-name", NULL);
252         if (ppartition_name)
253                 strlcpy(partition_name, ppartition_name,
254                                 sizeof(partition_name));
255         p_number_ptr = of_get_property(of_root, "ibm,partition-no", NULL);
256         if (p_number_ptr)
257                 partition_number = of_read_number(p_number_ptr, 1);
258         of_node_put(of_root);
259 }
260
261 static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
262 {
263         memset(&hostdata->madapter_info, 0x00,
264                         sizeof(hostdata->madapter_info));
265
266         dev_info(hostdata->dev, "SRP_VERSION: %s\n", SRP_VERSION);
267         strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);
268
269         strncpy(hostdata->madapter_info.partition_name, partition_name,
270                         sizeof(hostdata->madapter_info.partition_name));
271
272         hostdata->madapter_info.partition_number =
273                                         cpu_to_be32(partition_number);
274
275         hostdata->madapter_info.mad_version = cpu_to_be32(SRP_MAD_VERSION_1);
276         hostdata->madapter_info.os_type = cpu_to_be32(SRP_MAD_OS_LINUX);
277 }
278
279 /**
280  * ibmvscsi_reset_crq_queue() - resets a crq after a failure
281  * @queue:      crq_queue to initialize and register
282  * @hostdata:   ibmvscsi_host_data of host
283  */
284 static int ibmvscsi_reset_crq_queue(struct crq_queue *queue,
285                                     struct ibmvscsi_host_data *hostdata)
286 {
287         int rc = 0;
288         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
289
290         /* Close the CRQ */
291         do {
292                 if (rc)
293                         msleep(100);
294                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
295         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
296
297         /* Clean out the queue */
298         memset(queue->msgs, 0x00, PAGE_SIZE);
299         queue->cur = 0;
300
301         set_adapter_info(hostdata);
302
303         /* And re-open it again */
304         rc = plpar_hcall_norets(H_REG_CRQ,
305                                 vdev->unit_address,
306                                 queue->msg_token, PAGE_SIZE);
307         if (rc == H_CLOSED) {
308                 /* Adapter is good, but other end is not ready */
309                 dev_warn(hostdata->dev, "Partner adapter not ready\n");
310         } else if (rc != 0) {
311                 dev_warn(hostdata->dev, "couldn't register crq--rc 0x%x\n", rc);
312         }
313         return rc;
314 }
315
316 /**
317  * ibmvscsi_init_crq_queue() - Initializes and registers CRQ with hypervisor
318  * @queue:              crq_queue to initialize and register
319  * @hostdata:           ibmvscsi_host_data of host
320  * @max_requests:       maximum requests (unused)
321  *
322  * Allocates a page for messages, maps it for dma, and registers
323  * the crq with the hypervisor.
324  * Returns zero on success.
325  */
326 static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
327                                    struct ibmvscsi_host_data *hostdata,
328                                    int max_requests)
329 {
330         int rc;
331         int retrc;
332         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
333
334         queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
335
336         if (!queue->msgs)
337                 goto malloc_failed;
338         queue->size = PAGE_SIZE / sizeof(*queue->msgs);
339
340         queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
341                                           queue->size * sizeof(*queue->msgs),
342                                           DMA_BIDIRECTIONAL);
343
344         if (dma_mapping_error(hostdata->dev, queue->msg_token))
345                 goto map_failed;
346
347         gather_partition_info();
348         set_adapter_info(hostdata);
349
350         retrc = rc = plpar_hcall_norets(H_REG_CRQ,
351                                 vdev->unit_address,
352                                 queue->msg_token, PAGE_SIZE);
353         if (rc == H_RESOURCE)
354                 /* maybe kexecing and resource is busy. try a reset */
355                 rc = ibmvscsi_reset_crq_queue(queue,
356                                               hostdata);
357
358         if (rc == H_CLOSED) {
359                 /* Adapter is good, but other end is not ready */
360                 dev_warn(hostdata->dev, "Partner adapter not ready\n");
361                 retrc = 0;
362         } else if (rc != 0) {
363                 dev_warn(hostdata->dev, "Error %d opening adapter\n", rc);
364                 goto reg_crq_failed;
365         }
366
367         queue->cur = 0;
368         spin_lock_init(&queue->lock);
369
370         tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
371                      (unsigned long)hostdata);
372
373         if (request_irq(vdev->irq,
374                         ibmvscsi_handle_event,
375                         0, "ibmvscsi", (void *)hostdata) != 0) {
376                 dev_err(hostdata->dev, "couldn't register irq 0x%x\n",
377                         vdev->irq);
378                 goto req_irq_failed;
379         }
380
381         rc = vio_enable_interrupts(vdev);
382         if (rc != 0) {
383                 dev_err(hostdata->dev, "Error %d enabling interrupts!!!\n", rc);
384                 goto req_irq_failed;
385         }
386
387         return retrc;
388
389       req_irq_failed:
390         tasklet_kill(&hostdata->srp_task);
391         rc = 0;
392         do {
393                 if (rc)
394                         msleep(100);
395                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
396         } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
397       reg_crq_failed:
398         dma_unmap_single(hostdata->dev,
399                          queue->msg_token,
400                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
401       map_failed:
402         free_page((unsigned long)queue->msgs);
403       malloc_failed:
404         return -1;
405 }
406
407 /**
408  * ibmvscsi_reenable_crq_queue() - reenables a crq after
409  * @queue:      crq_queue to initialize and register
410  * @hostdata:   ibmvscsi_host_data of host
411  */
412 static int ibmvscsi_reenable_crq_queue(struct crq_queue *queue,
413                                        struct ibmvscsi_host_data *hostdata)
414 {
415         int rc = 0;
416         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
417
418         set_adapter_info(hostdata);
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 = VIOSRP_CRQ_CMD_RSP;
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  * 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 static void free_event_struct(struct event_pool *pool,
534                                        struct srp_event_struct *evt)
535 {
536         if (!valid_event_struct(pool, evt)) {
537                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
538                         "(not in pool %p)\n", evt, pool->events);
539                 return;
540         }
541         if (atomic_inc_return(&evt->free) != 1) {
542                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
543                         "which is not in use!\n", evt);
544                 return;
545         }
546 }
547
548 /**
549  * get_event_struct() - Gets the next free event in pool
550  * @pool:       event_pool that contains the events to be searched
551  *
552  * Returns the next event in "free" state, and NULL if none are free.
553  * Note that no synchronization is done here, we assume the host_lock
554  * will syncrhonze things.
555 */
556 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
557 {
558         int i;
559         int poolsize = pool->size;
560         int offset = pool->next;
561
562         for (i = 0; i < poolsize; i++) {
563                 offset = (offset + 1) % poolsize;
564                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
565                         pool->next = offset;
566                         return &pool->events[offset];
567                 }
568         }
569
570         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
571         return NULL;
572 }
573
574 /**
575  * init_event_struct: Initialize fields in an event struct that are always 
576  *                    required.
577  * @evt_struct: The event
578  * @done:       Routine to call when the event is responded to
579  * @format:     SRP or MAD format
580  * @timeout:    timeout value set in the CRQ
581  */
582 static void init_event_struct(struct srp_event_struct *evt_struct,
583                               void (*done) (struct srp_event_struct *),
584                               u8 format,
585                               int timeout)
586 {
587         evt_struct->cmnd = NULL;
588         evt_struct->cmnd_done = NULL;
589         evt_struct->sync_srp = NULL;
590         evt_struct->crq.format = format;
591         evt_struct->crq.timeout = cpu_to_be16(timeout);
592         evt_struct->done = done;
593 }
594
595 /* ------------------------------------------------------------
596  * Routines for receiving SCSI responses from the hosting partition
597  */
598
599 /*
600  * set_srp_direction: Set the fields in the srp related to data
601  *     direction and number of buffers based on the direction in
602  *     the scsi_cmnd and the number of buffers
603  */
604 static void set_srp_direction(struct scsi_cmnd *cmd,
605                               struct srp_cmd *srp_cmd, 
606                               int numbuf)
607 {
608         u8 fmt;
609
610         if (numbuf == 0)
611                 return;
612         
613         if (numbuf == 1)
614                 fmt = SRP_DATA_DESC_DIRECT;
615         else {
616                 fmt = SRP_DATA_DESC_INDIRECT;
617                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
618
619                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
620                         srp_cmd->data_out_desc_cnt = numbuf;
621                 else
622                         srp_cmd->data_in_desc_cnt = numbuf;
623         }
624
625         if (cmd->sc_data_direction == DMA_TO_DEVICE)
626                 srp_cmd->buf_fmt = fmt << 4;
627         else
628                 srp_cmd->buf_fmt = fmt;
629 }
630
631 /**
632  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
633  * @cmd:        srp_cmd whose additional_data member will be unmapped
634  * @evt_struct: the event
635  * @dev:        device for which the memory is mapped
636  */
637 static void unmap_cmd_data(struct srp_cmd *cmd,
638                            struct srp_event_struct *evt_struct,
639                            struct device *dev)
640 {
641         u8 out_fmt, in_fmt;
642
643         out_fmt = cmd->buf_fmt >> 4;
644         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
645
646         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
647                 return;
648
649         if (evt_struct->cmnd)
650                 scsi_dma_unmap(evt_struct->cmnd);
651 }
652
653 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
654                        struct srp_direct_buf *md)
655 {
656         int i;
657         struct scatterlist *sg;
658         u64 total_length = 0;
659
660         scsi_for_each_sg(cmd, sg, nseg, i) {
661                 struct srp_direct_buf *descr = md + i;
662                 descr->va = cpu_to_be64(sg_dma_address(sg));
663                 descr->len = cpu_to_be32(sg_dma_len(sg));
664                 descr->key = 0;
665                 total_length += sg_dma_len(sg);
666         }
667         return total_length;
668 }
669
670 /**
671  * map_sg_data: - Maps dma for a scatterlist and initializes descriptor fields
672  * @cmd:        struct scsi_cmnd with the scatterlist
673  * @evt_struct: struct srp_event_struct to map
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 = dma_alloc_coherent(dev,
721                                            SG_ALL * sizeof(struct srp_direct_buf),
722                                            &evt_struct->ext_list_token, 0);
723                 if (!evt_struct->ext_list) {
724                         if (!firmware_has_feature(FW_FEATURE_CMO))
725                                 sdev_printk(KERN_ERR, cmd->device,
726                                             "Can't allocate memory "
727                                             "for indirect table\n");
728                         scsi_dma_unmap(cmd);
729                         return 0;
730                 }
731         }
732
733         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
734
735         indirect->len = cpu_to_be32(total_length);
736         indirect->table_desc.va = cpu_to_be64(evt_struct->ext_list_token);
737         indirect->table_desc.len = cpu_to_be32(sg_mapped *
738                                                sizeof(indirect->desc_list[0]));
739         memcpy(indirect->desc_list, evt_struct->ext_list,
740                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
741         return 1;
742 }
743
744 /**
745  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
746  * @cmd:        struct scsi_cmnd with the memory to be mapped
747  * @evt_struct: struct srp_event_struct to map
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  * @error_code:  error code to return as the 'result'
782  */
783 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
784 {
785         struct srp_event_struct *evt;
786         unsigned long flags;
787
788         spin_lock_irqsave(hostdata->host->host_lock, flags);
789         while (!list_empty(&hostdata->sent)) {
790                 evt = list_first_entry(&hostdata->sent, struct srp_event_struct, list);
791                 list_del(&evt->list);
792                 del_timer(&evt->timer);
793
794                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
795                 if (evt->cmnd) {
796                         evt->cmnd->result = (error_code << 16);
797                         unmap_cmd_data(&evt->iu.srp.cmd, evt,
798                                        evt->hostdata->dev);
799                         if (evt->cmnd_done)
800                                 evt->cmnd_done(evt->cmnd);
801                 } else if (evt->done && evt->crq.format != VIOSRP_MAD_FORMAT &&
802                            evt->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
803                         evt->done(evt);
804                 free_event_struct(&evt->hostdata->pool, evt);
805                 spin_lock_irqsave(hostdata->host->host_lock, flags);
806         }
807         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
808 }
809
810 /**
811  * ibmvscsi_set_request_limit - Set the adapter request_limit in response to
812  * an adapter failure, reset, or SRP Login. Done under host lock to prevent
813  * race with SCSI command submission.
814  * @hostdata:   adapter to adjust
815  * @limit:      new request limit
816  */
817 static void ibmvscsi_set_request_limit(struct ibmvscsi_host_data *hostdata, int limit)
818 {
819         unsigned long flags;
820
821         spin_lock_irqsave(hostdata->host->host_lock, flags);
822         atomic_set(&hostdata->request_limit, limit);
823         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
824 }
825
826 /**
827  * ibmvscsi_reset_host - Reset the connection to the server
828  * @hostdata:   struct ibmvscsi_host_data to reset
829 */
830 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
831 {
832         scsi_block_requests(hostdata->host);
833         ibmvscsi_set_request_limit(hostdata, 0);
834
835         purge_requests(hostdata, DID_ERROR);
836         hostdata->action = IBMVSCSI_HOST_ACTION_RESET;
837         wake_up(&hostdata->work_wait_q);
838 }
839
840 /**
841  * ibmvscsi_timeout - Internal command timeout handler
842  * @t:  struct srp_event_struct that timed out
843  *
844  * Called when an internally generated command times out
845 */
846 static void ibmvscsi_timeout(struct timer_list *t)
847 {
848         struct srp_event_struct *evt_struct = from_timer(evt_struct, t, timer);
849         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
850
851         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
852                 evt_struct->iu.srp.cmd.opcode);
853
854         ibmvscsi_reset_host(hostdata);
855 }
856
857
858 /* ------------------------------------------------------------
859  * Routines for sending and receiving SRPs
860  */
861 /**
862  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
863  * @evt_struct: evt_struct to be sent
864  * @hostdata:   ibmvscsi_host_data of host
865  * @timeout:    timeout in seconds - 0 means do not time command
866  *
867  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
868  * Note that this routine assumes that host_lock is held for synchronization
869 */
870 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
871                                    struct ibmvscsi_host_data *hostdata,
872                                    unsigned long timeout)
873 {
874         __be64 *crq_as_u64 = (__be64 *)&evt_struct->crq;
875         int request_status = 0;
876         int rc;
877         int srp_req = 0;
878
879         /* If we have exhausted our request limit, just fail this request,
880          * unless it is for a reset or abort.
881          * Note that there are rare cases involving driver generated requests 
882          * (such as task management requests) that the mid layer may think we
883          * can handle more requests (can_queue) when we actually can't
884          */
885         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
886                 srp_req = 1;
887                 request_status =
888                         atomic_dec_if_positive(&hostdata->request_limit);
889                 /* If request limit was -1 when we started, it is now even
890                  * less than that
891                  */
892                 if (request_status < -1)
893                         goto send_error;
894                 /* Otherwise, we may have run out of requests. */
895                 /* If request limit was 0 when we started the adapter is in the
896                  * process of performing a login with the server adapter, or
897                  * we may have run out of requests.
898                  */
899                 else if (request_status == -1 &&
900                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
901                         goto send_busy;
902                 /* Abort and reset calls should make it through.
903                  * Nothing except abort and reset should use the last two
904                  * slots unless we had two or less to begin with.
905                  */
906                 else if (request_status < 2 &&
907                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
908                         /* In the case that we have less than two requests
909                          * available, check the server limit as a combination
910                          * of the request limit and the number of requests
911                          * in-flight (the size of the send list).  If the
912                          * server limit is greater than 2, return busy so
913                          * that the last two are reserved for reset and abort.
914                          */
915                         int server_limit = request_status;
916                         struct srp_event_struct *tmp_evt;
917
918                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
919                                 server_limit++;
920                         }
921
922                         if (server_limit > 2)
923                                 goto send_busy;
924                 }
925         }
926
927         /* Copy the IU into the transfer area */
928         *evt_struct->xfer_iu = evt_struct->iu;
929         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
930
931         /* Add this to the sent list.  We need to do this 
932          * before we actually send 
933          * in case it comes back REALLY fast
934          */
935         list_add_tail(&evt_struct->list, &hostdata->sent);
936
937         timer_setup(&evt_struct->timer, ibmvscsi_timeout, 0);
938         if (timeout) {
939                 evt_struct->timer.expires = jiffies + (timeout * HZ);
940                 add_timer(&evt_struct->timer);
941         }
942
943         rc = ibmvscsi_send_crq(hostdata, be64_to_cpu(crq_as_u64[0]),
944                                be64_to_cpu(crq_as_u64[1]));
945         if (rc != 0) {
946                 list_del(&evt_struct->list);
947                 del_timer(&evt_struct->timer);
948
949                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
950                  * Firmware will send a CRQ with a transport event (0xFF) to
951                  * tell this client what has happened to the transport.  This
952                  * will be handled in ibmvscsi_handle_crq()
953                  */
954                 if (rc == H_CLOSED) {
955                         dev_warn(hostdata->dev, "send warning. "
956                                  "Receive queue closed, will retry.\n");
957                         goto send_busy;
958                 }
959                 dev_err(hostdata->dev, "send error %d\n", rc);
960                 if (srp_req)
961                         atomic_inc(&hostdata->request_limit);
962                 goto send_error;
963         }
964
965         return 0;
966
967  send_busy:
968         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
969
970         free_event_struct(&hostdata->pool, evt_struct);
971         if (srp_req && request_status != -1)
972                 atomic_inc(&hostdata->request_limit);
973         return SCSI_MLQUEUE_HOST_BUSY;
974
975  send_error:
976         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
977
978         if (evt_struct->cmnd != NULL) {
979                 evt_struct->cmnd->result = DID_ERROR << 16;
980                 evt_struct->cmnd_done(evt_struct->cmnd);
981         } else if (evt_struct->done)
982                 evt_struct->done(evt_struct);
983
984         free_event_struct(&hostdata->pool, evt_struct);
985         return 0;
986 }
987
988 /**
989  * handle_cmd_rsp: -  Handle responses from commands
990  * @evt_struct: srp_event_struct to be handled
991  *
992  * Used as a callback by when sending scsi cmds.
993  * Gets called by ibmvscsi_handle_crq()
994 */
995 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
996 {
997         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
998         struct scsi_cmnd *cmnd = evt_struct->cmnd;
999
1000         if (unlikely(rsp->opcode != SRP_RSP)) {
1001                 if (printk_ratelimit())
1002                         dev_warn(evt_struct->hostdata->dev,
1003                                  "bad SRP RSP type %#02x\n", rsp->opcode);
1004         }
1005         
1006         if (cmnd) {
1007                 cmnd->result |= rsp->status;
1008                 if (scsi_status_is_check_condition(cmnd->result))
1009                         memcpy(cmnd->sense_buffer,
1010                                rsp->data,
1011                                be32_to_cpu(rsp->sense_data_len));
1012                 unmap_cmd_data(&evt_struct->iu.srp.cmd, 
1013                                evt_struct, 
1014                                evt_struct->hostdata->dev);
1015
1016                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
1017                         scsi_set_resid(cmnd,
1018                                        be32_to_cpu(rsp->data_out_res_cnt));
1019                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
1020                         scsi_set_resid(cmnd, be32_to_cpu(rsp->data_in_res_cnt));
1021         }
1022
1023         if (evt_struct->cmnd_done)
1024                 evt_struct->cmnd_done(cmnd);
1025 }
1026
1027 /**
1028  * lun_from_dev: - Returns the lun of the scsi device
1029  * @dev:        struct scsi_device
1030  *
1031 */
1032 static inline u16 lun_from_dev(struct scsi_device *dev)
1033 {
1034         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
1035 }
1036
1037 /**
1038  * ibmvscsi_queuecommand_lck() - The queuecommand function of the scsi template
1039  * @cmnd:       struct scsi_cmnd to be executed
1040  * @done:       Callback function to be called when cmd is completed
1041 */
1042 static int ibmvscsi_queuecommand_lck(struct scsi_cmnd *cmnd,
1043                                  void (*done) (struct scsi_cmnd *))
1044 {
1045         struct srp_cmd *srp_cmd;
1046         struct srp_event_struct *evt_struct;
1047         struct srp_indirect_buf *indirect;
1048         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
1049         u16 lun = lun_from_dev(cmnd->device);
1050         u8 out_fmt, in_fmt;
1051
1052         cmnd->result = (DID_OK << 16);
1053         evt_struct = get_event_struct(&hostdata->pool);
1054         if (!evt_struct)
1055                 return SCSI_MLQUEUE_HOST_BUSY;
1056
1057         /* Set up the actual SRP IU */
1058         srp_cmd = &evt_struct->iu.srp.cmd;
1059         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
1060         srp_cmd->opcode = SRP_CMD;
1061         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
1062         int_to_scsilun(lun, &srp_cmd->lun);
1063
1064         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
1065                 if (!firmware_has_feature(FW_FEATURE_CMO))
1066                         sdev_printk(KERN_ERR, cmnd->device,
1067                                     "couldn't convert cmd to srp_cmd\n");
1068                 free_event_struct(&hostdata->pool, evt_struct);
1069                 return SCSI_MLQUEUE_HOST_BUSY;
1070         }
1071
1072         init_event_struct(evt_struct,
1073                           handle_cmd_rsp,
1074                           VIOSRP_SRP_FORMAT,
1075                           cmnd->request->timeout/HZ);
1076
1077         evt_struct->cmnd = cmnd;
1078         evt_struct->cmnd_done = done;
1079
1080         /* Fix up dma address of the buffer itself */
1081         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
1082         out_fmt = srp_cmd->buf_fmt >> 4;
1083         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
1084         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
1085              out_fmt == SRP_DATA_DESC_INDIRECT) &&
1086             indirect->table_desc.va == 0) {
1087                 indirect->table_desc.va =
1088                         cpu_to_be64(be64_to_cpu(evt_struct->crq.IU_data_ptr) +
1089                         offsetof(struct srp_cmd, add_data) +
1090                         offsetof(struct srp_indirect_buf, desc_list));
1091         }
1092
1093         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
1094 }
1095
1096 static DEF_SCSI_QCMD(ibmvscsi_queuecommand)
1097
1098 /* ------------------------------------------------------------
1099  * Routines for driver initialization
1100  */
1101
1102 /**
1103  * map_persist_bufs: - Pre-map persistent data for adapter logins
1104  * @hostdata:   ibmvscsi_host_data of host
1105  *
1106  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
1107  * Return 1 on error, 0 on success.
1108  */
1109 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
1110 {
1111
1112         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
1113                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1114
1115         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
1116                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
1117                 return 1;
1118         }
1119
1120         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
1121                                                      &hostdata->madapter_info,
1122                                                      sizeof(hostdata->madapter_info),
1123                                                      DMA_BIDIRECTIONAL);
1124         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
1125                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
1126                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
1127                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1128                 return 1;
1129         }
1130
1131         return 0;
1132 }
1133
1134 /**
1135  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
1136  * @hostdata:   ibmvscsi_host_data of host
1137  *
1138  * Unmap the capabilities and adapter info DMA buffers
1139  */
1140 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
1141 {
1142         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
1143                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
1144
1145         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
1146                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
1147 }
1148
1149 /**
1150  * login_rsp: - Handle response to SRP login request
1151  * @evt_struct: srp_event_struct with the response
1152  *
1153  * Used as a "done" callback by when sending srp_login. Gets called
1154  * by ibmvscsi_handle_crq()
1155 */
1156 static void login_rsp(struct srp_event_struct *evt_struct)
1157 {
1158         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1159         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
1160         case SRP_LOGIN_RSP:     /* it worked! */
1161                 break;
1162         case SRP_LOGIN_REJ:     /* refused! */
1163                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
1164                          evt_struct->xfer_iu->srp.login_rej.reason);
1165                 /* Login failed.  */
1166                 ibmvscsi_set_request_limit(hostdata, -1);
1167                 return;
1168         default:
1169                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
1170                         evt_struct->xfer_iu->srp.login_rsp.opcode);
1171                 /* Login failed.  */
1172                 ibmvscsi_set_request_limit(hostdata, -1);
1173                 return;
1174         }
1175
1176         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
1177         hostdata->client_migrated = 0;
1178
1179         /* Now we know what the real request-limit is.
1180          * This value is set rather than added to request_limit because
1181          * request_limit could have been set to -1 by this client.
1182          */
1183         ibmvscsi_set_request_limit(hostdata,
1184                    be32_to_cpu(evt_struct->xfer_iu->srp.login_rsp.req_lim_delta));
1185
1186         /* If we had any pending I/Os, kick them */
1187         hostdata->action = IBMVSCSI_HOST_ACTION_UNBLOCK;
1188         wake_up(&hostdata->work_wait_q);
1189 }
1190
1191 /**
1192  * send_srp_login: - Sends the srp login
1193  * @hostdata:   ibmvscsi_host_data of host
1194  *
1195  * Returns zero if successful.
1196 */
1197 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
1198 {
1199         int rc;
1200         unsigned long flags;
1201         struct srp_login_req *login;
1202         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
1203
1204         BUG_ON(!evt_struct);
1205         init_event_struct(evt_struct, login_rsp,
1206                           VIOSRP_SRP_FORMAT, login_timeout);
1207
1208         login = &evt_struct->iu.srp.login_req;
1209         memset(login, 0, sizeof(*login));
1210         login->opcode = SRP_LOGIN_REQ;
1211         login->req_it_iu_len = cpu_to_be32(sizeof(union srp_iu));
1212         login->req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
1213                                          SRP_BUF_FORMAT_INDIRECT);
1214
1215         /* Start out with a request limit of 0, since this is negotiated in
1216          * the login request we are just sending and login requests always
1217          * get sent by the driver regardless of request_limit.
1218          */
1219         ibmvscsi_set_request_limit(hostdata, 0);
1220
1221         spin_lock_irqsave(hostdata->host->host_lock, flags);
1222         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
1223         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1224         dev_info(hostdata->dev, "sent SRP login\n");
1225         return rc;
1226 };
1227
1228 /**
1229  * capabilities_rsp: - Handle response to MAD adapter capabilities request
1230  * @evt_struct: srp_event_struct with the response
1231  *
1232  * Used as a "done" callback by when sending adapter_info.
1233  */
1234 static void capabilities_rsp(struct srp_event_struct *evt_struct)
1235 {
1236         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1237
1238         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
1239                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
1240                         evt_struct->xfer_iu->mad.capabilities.common.status);
1241         } else {
1242                 if (hostdata->caps.migration.common.server_support !=
1243                     cpu_to_be16(SERVER_SUPPORTS_CAP))
1244                         dev_info(hostdata->dev, "Partition migration not supported\n");
1245
1246                 if (client_reserve) {
1247                         if (hostdata->caps.reserve.common.server_support ==
1248                             cpu_to_be16(SERVER_SUPPORTS_CAP))
1249                                 dev_info(hostdata->dev, "Client reserve enabled\n");
1250                         else
1251                                 dev_info(hostdata->dev, "Client reserve not supported\n");
1252                 }
1253         }
1254
1255         send_srp_login(hostdata);
1256 }
1257
1258 /**
1259  * send_mad_capabilities: - Sends the mad capabilities request
1260  *      and stores the result so it can be retrieved with
1261  * @hostdata:   ibmvscsi_host_data of host
1262  */
1263 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
1264 {
1265         struct viosrp_capabilities *req;
1266         struct srp_event_struct *evt_struct;
1267         unsigned long flags;
1268         struct device_node *of_node = hostdata->dev->of_node;
1269         const char *location;
1270
1271         evt_struct = get_event_struct(&hostdata->pool);
1272         BUG_ON(!evt_struct);
1273
1274         init_event_struct(evt_struct, capabilities_rsp,
1275                           VIOSRP_MAD_FORMAT, info_timeout);
1276
1277         req = &evt_struct->iu.mad.capabilities;
1278         memset(req, 0, sizeof(*req));
1279
1280         hostdata->caps.flags = cpu_to_be32(CAP_LIST_SUPPORTED);
1281         if (hostdata->client_migrated)
1282                 hostdata->caps.flags |= cpu_to_be32(CLIENT_MIGRATED);
1283
1284         strlcpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
1285                 sizeof(hostdata->caps.name));
1286
1287         location = of_get_property(of_node, "ibm,loc-code", NULL);
1288         location = location ? location : dev_name(hostdata->dev);
1289         strlcpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
1290
1291         req->common.type = cpu_to_be32(VIOSRP_CAPABILITIES_TYPE);
1292         req->buffer = cpu_to_be64(hostdata->caps_addr);
1293
1294         hostdata->caps.migration.common.cap_type =
1295                                 cpu_to_be32(MIGRATION_CAPABILITIES);
1296         hostdata->caps.migration.common.length =
1297                                 cpu_to_be16(sizeof(hostdata->caps.migration));
1298         hostdata->caps.migration.common.server_support =
1299                                 cpu_to_be16(SERVER_SUPPORTS_CAP);
1300         hostdata->caps.migration.ecl = cpu_to_be32(1);
1301
1302         if (client_reserve) {
1303                 hostdata->caps.reserve.common.cap_type =
1304                                         cpu_to_be32(RESERVATION_CAPABILITIES);
1305                 hostdata->caps.reserve.common.length =
1306                                 cpu_to_be16(sizeof(hostdata->caps.reserve));
1307                 hostdata->caps.reserve.common.server_support =
1308                                 cpu_to_be16(SERVER_SUPPORTS_CAP);
1309                 hostdata->caps.reserve.type =
1310                                 cpu_to_be32(CLIENT_RESERVE_SCSI_2);
1311                 req->common.length =
1312                                 cpu_to_be16(sizeof(hostdata->caps));
1313         } else
1314                 req->common.length = cpu_to_be16(sizeof(hostdata->caps) -
1315                                                 sizeof(hostdata->caps.reserve));
1316
1317         spin_lock_irqsave(hostdata->host->host_lock, flags);
1318         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1319                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
1320         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1321 };
1322
1323 /**
1324  * fast_fail_rsp: - Handle response to MAD enable fast fail
1325  * @evt_struct: srp_event_struct with the response
1326  *
1327  * Used as a "done" callback by when sending enable fast fail. Gets called
1328  * by ibmvscsi_handle_crq()
1329  */
1330 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
1331 {
1332         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1333         u16 status = be16_to_cpu(evt_struct->xfer_iu->mad.fast_fail.common.status);
1334
1335         if (status == VIOSRP_MAD_NOT_SUPPORTED)
1336                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
1337         else if (status == VIOSRP_MAD_FAILED)
1338                 dev_err(hostdata->dev, "fast_fail request failed\n");
1339         else if (status != VIOSRP_MAD_SUCCESS)
1340                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
1341
1342         send_mad_capabilities(hostdata);
1343 }
1344
1345 /**
1346  * enable_fast_fail() - Start host initialization
1347  * @hostdata:   ibmvscsi_host_data of host
1348  *
1349  * Returns zero if successful.
1350  */
1351 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1352 {
1353         int rc;
1354         unsigned long flags;
1355         struct viosrp_fast_fail *fast_fail_mad;
1356         struct srp_event_struct *evt_struct;
1357
1358         if (!fast_fail) {
1359                 send_mad_capabilities(hostdata);
1360                 return 0;
1361         }
1362
1363         evt_struct = get_event_struct(&hostdata->pool);
1364         BUG_ON(!evt_struct);
1365
1366         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1367
1368         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1369         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1370         fast_fail_mad->common.type = cpu_to_be32(VIOSRP_ENABLE_FAST_FAIL);
1371         fast_fail_mad->common.length = cpu_to_be16(sizeof(*fast_fail_mad));
1372
1373         spin_lock_irqsave(hostdata->host->host_lock, flags);
1374         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1375         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1376         return rc;
1377 }
1378
1379 /**
1380  * adapter_info_rsp: - Handle response to MAD adapter info request
1381  * @evt_struct: srp_event_struct with the response
1382  *
1383  * Used as a "done" callback by when sending adapter_info. Gets called
1384  * by ibmvscsi_handle_crq()
1385 */
1386 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1387 {
1388         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1389
1390         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1391                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1392                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1393         } else {
1394                 dev_info(hostdata->dev, "host srp version: %s, "
1395                          "host partition %s (%d), OS %d, max io %u\n",
1396                          hostdata->madapter_info.srp_version,
1397                          hostdata->madapter_info.partition_name,
1398                          be32_to_cpu(hostdata->madapter_info.partition_number),
1399                          be32_to_cpu(hostdata->madapter_info.os_type),
1400                          be32_to_cpu(hostdata->madapter_info.port_max_txu[0]));
1401                 
1402                 if (hostdata->madapter_info.port_max_txu[0]) 
1403                         hostdata->host->max_sectors = 
1404                                 be32_to_cpu(hostdata->madapter_info.port_max_txu[0]) >> 9;
1405                 
1406                 if (be32_to_cpu(hostdata->madapter_info.os_type) == SRP_MAD_OS_AIX &&
1407                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1408                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1409                                 hostdata->madapter_info.srp_version);
1410                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1411                                 MAX_INDIRECT_BUFS);
1412                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1413                 }
1414
1415                 if (be32_to_cpu(hostdata->madapter_info.os_type) == SRP_MAD_OS_AIX) {
1416                         enable_fast_fail(hostdata);
1417                         return;
1418                 }
1419         }
1420
1421         send_srp_login(hostdata);
1422 }
1423
1424 /**
1425  * send_mad_adapter_info: - Sends the mad adapter info request
1426  *      and stores the result so it can be retrieved with
1427  *      sysfs.  We COULD consider causing a failure if the
1428  *      returned SRP version doesn't match ours.
1429  * @hostdata:   ibmvscsi_host_data of host
1430  * 
1431  * Returns zero if successful.
1432 */
1433 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1434 {
1435         struct viosrp_adapter_info *req;
1436         struct srp_event_struct *evt_struct;
1437         unsigned long flags;
1438
1439         evt_struct = get_event_struct(&hostdata->pool);
1440         BUG_ON(!evt_struct);
1441
1442         init_event_struct(evt_struct,
1443                           adapter_info_rsp,
1444                           VIOSRP_MAD_FORMAT,
1445                           info_timeout);
1446         
1447         req = &evt_struct->iu.mad.adapter_info;
1448         memset(req, 0x00, sizeof(*req));
1449         
1450         req->common.type = cpu_to_be32(VIOSRP_ADAPTER_INFO_TYPE);
1451         req->common.length = cpu_to_be16(sizeof(hostdata->madapter_info));
1452         req->buffer = cpu_to_be64(hostdata->adapter_info_addr);
1453
1454         spin_lock_irqsave(hostdata->host->host_lock, flags);
1455         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1456                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1457         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1458 };
1459
1460 /*
1461  * init_adapter() - Start virtual adapter initialization sequence
1462  */
1463 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1464 {
1465         send_mad_adapter_info(hostdata);
1466 }
1467
1468 /*
1469  * sync_completion: Signal that a synchronous command has completed
1470  * Note that after returning from this call, the evt_struct is freed.
1471  * the caller waiting on this completion shouldn't touch the evt_struct
1472  * again.
1473  */
1474 static void sync_completion(struct srp_event_struct *evt_struct)
1475 {
1476         /* copy the response back */
1477         if (evt_struct->sync_srp)
1478                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1479         
1480         complete(&evt_struct->comp);
1481 }
1482
1483 /*
1484  * ibmvscsi_eh_abort_handler: Abort a command...from scsi host template
1485  * send this over to the server and wait synchronously for the response
1486  */
1487 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1488 {
1489         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1490         struct srp_tsk_mgmt *tsk_mgmt;
1491         struct srp_event_struct *evt;
1492         struct srp_event_struct *tmp_evt, *found_evt;
1493         union viosrp_iu srp_rsp;
1494         int rsp_rc;
1495         unsigned long flags;
1496         u16 lun = lun_from_dev(cmd->device);
1497         unsigned long wait_switch = 0;
1498
1499         /* First, find this command in our sent list so we can figure
1500          * out the correct tag
1501          */
1502         spin_lock_irqsave(hostdata->host->host_lock, flags);
1503         wait_switch = jiffies + (init_timeout * HZ);
1504         do {
1505                 found_evt = NULL;
1506                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1507                         if (tmp_evt->cmnd == cmd) {
1508                                 found_evt = tmp_evt;
1509                                 break;
1510                         }
1511                 }
1512
1513                 if (!found_evt) {
1514                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1515                         return SUCCESS;
1516                 }
1517
1518                 evt = get_event_struct(&hostdata->pool);
1519                 if (evt == NULL) {
1520                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1521                         sdev_printk(KERN_ERR, cmd->device,
1522                                 "failed to allocate abort event\n");
1523                         return FAILED;
1524                 }
1525         
1526                 init_event_struct(evt,
1527                                   sync_completion,
1528                                   VIOSRP_SRP_FORMAT,
1529                                   abort_timeout);
1530
1531                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1532         
1533                 /* Set up an abort SRP command */
1534                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1535                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1536                 int_to_scsilun(lun, &tsk_mgmt->lun);
1537                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1538                 tsk_mgmt->task_tag = (u64) found_evt;
1539
1540                 evt->sync_srp = &srp_rsp;
1541
1542                 init_completion(&evt->comp);
1543                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1544
1545                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1546                         break;
1547
1548                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1549                 msleep(10);
1550                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1551         } while (time_before(jiffies, wait_switch));
1552
1553         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1554
1555         if (rsp_rc != 0) {
1556                 sdev_printk(KERN_ERR, cmd->device,
1557                             "failed to send abort() event. rc=%d\n", rsp_rc);
1558                 return FAILED;
1559         }
1560
1561         sdev_printk(KERN_INFO, cmd->device,
1562                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1563                     (((u64) lun) << 48), (u64) found_evt);
1564
1565         wait_for_completion(&evt->comp);
1566
1567         /* make sure we got a good response */
1568         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1569                 if (printk_ratelimit())
1570                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1571                                     srp_rsp.srp.rsp.opcode);
1572                 return FAILED;
1573         }
1574
1575         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1576                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1577         else
1578                 rsp_rc = srp_rsp.srp.rsp.status;
1579
1580         if (rsp_rc) {
1581                 if (printk_ratelimit())
1582                         sdev_printk(KERN_WARNING, cmd->device,
1583                                     "abort code %d for task tag 0x%llx\n",
1584                                     rsp_rc, tsk_mgmt->task_tag);
1585                 return FAILED;
1586         }
1587
1588         /* Because we dropped the spinlock above, it's possible
1589          * The event is no longer in our list.  Make sure it didn't
1590          * complete while we were aborting
1591          */
1592         spin_lock_irqsave(hostdata->host->host_lock, flags);
1593         found_evt = NULL;
1594         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1595                 if (tmp_evt->cmnd == cmd) {
1596                         found_evt = tmp_evt;
1597                         break;
1598                 }
1599         }
1600
1601         if (found_evt == NULL) {
1602                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1603                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1604                             tsk_mgmt->task_tag);
1605                 return SUCCESS;
1606         }
1607
1608         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1609                     tsk_mgmt->task_tag);
1610
1611         cmd->result = (DID_ABORT << 16);
1612         list_del(&found_evt->list);
1613         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1614                        found_evt->hostdata->dev);
1615         free_event_struct(&found_evt->hostdata->pool, found_evt);
1616         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1617         atomic_inc(&hostdata->request_limit);
1618         return SUCCESS;
1619 }
1620
1621 /*
1622  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host 
1623  * template send this over to the server and wait synchronously for the 
1624  * response
1625  */
1626 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1627 {
1628         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1629         struct srp_tsk_mgmt *tsk_mgmt;
1630         struct srp_event_struct *evt;
1631         struct srp_event_struct *tmp_evt, *pos;
1632         union viosrp_iu srp_rsp;
1633         int rsp_rc;
1634         unsigned long flags;
1635         u16 lun = lun_from_dev(cmd->device);
1636         unsigned long wait_switch = 0;
1637
1638         spin_lock_irqsave(hostdata->host->host_lock, flags);
1639         wait_switch = jiffies + (init_timeout * HZ);
1640         do {
1641                 evt = get_event_struct(&hostdata->pool);
1642                 if (evt == NULL) {
1643                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1644                         sdev_printk(KERN_ERR, cmd->device,
1645                                 "failed to allocate reset event\n");
1646                         return FAILED;
1647                 }
1648         
1649                 init_event_struct(evt,
1650                                   sync_completion,
1651                                   VIOSRP_SRP_FORMAT,
1652                                   reset_timeout);
1653
1654                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1655
1656                 /* Set up a lun reset SRP command */
1657                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1658                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1659                 int_to_scsilun(lun, &tsk_mgmt->lun);
1660                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1661
1662                 evt->sync_srp = &srp_rsp;
1663
1664                 init_completion(&evt->comp);
1665                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1666
1667                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1668                         break;
1669
1670                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1671                 msleep(10);
1672                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1673         } while (time_before(jiffies, wait_switch));
1674
1675         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1676
1677         if (rsp_rc != 0) {
1678                 sdev_printk(KERN_ERR, cmd->device,
1679                             "failed to send reset event. rc=%d\n", rsp_rc);
1680                 return FAILED;
1681         }
1682
1683         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1684                     (((u64) lun) << 48));
1685
1686         wait_for_completion(&evt->comp);
1687
1688         /* make sure we got a good response */
1689         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1690                 if (printk_ratelimit())
1691                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1692                                     srp_rsp.srp.rsp.opcode);
1693                 return FAILED;
1694         }
1695
1696         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1697                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1698         else
1699                 rsp_rc = srp_rsp.srp.rsp.status;
1700
1701         if (rsp_rc) {
1702                 if (printk_ratelimit())
1703                         sdev_printk(KERN_WARNING, cmd->device,
1704                                     "reset code %d for task tag 0x%llx\n",
1705                                     rsp_rc, tsk_mgmt->task_tag);
1706                 return FAILED;
1707         }
1708
1709         /* We need to find all commands for this LUN that have not yet been
1710          * responded to, and fail them with DID_RESET
1711          */
1712         spin_lock_irqsave(hostdata->host->host_lock, flags);
1713         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1714                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1715                         if (tmp_evt->cmnd)
1716                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1717                         list_del(&tmp_evt->list);
1718                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1719                                        tmp_evt->hostdata->dev);
1720                         free_event_struct(&tmp_evt->hostdata->pool,
1721                                                    tmp_evt);
1722                         atomic_inc(&hostdata->request_limit);
1723                         if (tmp_evt->cmnd_done)
1724                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1725                         else if (tmp_evt->done)
1726                                 tmp_evt->done(tmp_evt);
1727                 }
1728         }
1729         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1730         return SUCCESS;
1731 }
1732
1733 /**
1734  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1735  * @cmd:        struct scsi_cmnd having problems
1736 */
1737 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1738 {
1739         unsigned long wait_switch = 0;
1740         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1741
1742         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1743
1744         ibmvscsi_reset_host(hostdata);
1745
1746         for (wait_switch = jiffies + (init_timeout * HZ);
1747              time_before(jiffies, wait_switch) &&
1748                      atomic_read(&hostdata->request_limit) < 2;) {
1749
1750                 msleep(10);
1751         }
1752
1753         if (atomic_read(&hostdata->request_limit) <= 0)
1754                 return FAILED;
1755
1756         return SUCCESS;
1757 }
1758
1759 /**
1760  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1761  * @crq:        Command/Response queue
1762  * @hostdata:   ibmvscsi_host_data of host
1763  *
1764 */
1765 static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1766                                 struct ibmvscsi_host_data *hostdata)
1767 {
1768         long rc;
1769         unsigned long flags;
1770         /* The hypervisor copies our tag value here so no byteswapping */
1771         struct srp_event_struct *evt_struct =
1772                         (__force struct srp_event_struct *)crq->IU_data_ptr;
1773         switch (crq->valid) {
1774         case VIOSRP_CRQ_INIT_RSP:               /* initialization */
1775                 switch (crq->format) {
1776                 case VIOSRP_CRQ_INIT:   /* Initialization message */
1777                         dev_info(hostdata->dev, "partner initialized\n");
1778                         /* Send back a response */
1779                         rc = ibmvscsi_send_crq(hostdata, 0xC002000000000000LL, 0);
1780                         if (rc == 0) {
1781                                 /* Now login */
1782                                 init_adapter(hostdata);
1783                         } else {
1784                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1785                         }
1786
1787                         break;
1788                 case VIOSRP_CRQ_INIT_COMPLETE:  /* Initialization response */
1789                         dev_info(hostdata->dev, "partner initialization complete\n");
1790
1791                         /* Now login */
1792                         init_adapter(hostdata);
1793                         break;
1794                 default:
1795                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1796                 }
1797                 return;
1798         case VIOSRP_CRQ_XPORT_EVENT:    /* Hypervisor telling us the connection is closed */
1799                 scsi_block_requests(hostdata->host);
1800                 ibmvscsi_set_request_limit(hostdata, 0);
1801                 if (crq->format == 0x06) {
1802                         /* We need to re-setup the interpartition connection */
1803                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1804                         hostdata->client_migrated = 1;
1805                         hostdata->action = IBMVSCSI_HOST_ACTION_REENABLE;
1806                         purge_requests(hostdata, DID_REQUEUE);
1807                         wake_up(&hostdata->work_wait_q);
1808                 } else {
1809                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1810                                 crq->format);
1811                         ibmvscsi_reset_host(hostdata);
1812                 }
1813                 return;
1814         case VIOSRP_CRQ_CMD_RSP:                /* real payload */
1815                 break;
1816         default:
1817                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1818                         crq->valid);
1819                 return;
1820         }
1821
1822         /* The only kind of payload CRQs we should get are responses to
1823          * things we send. Make sure this response is to something we
1824          * actually sent
1825          */
1826         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1827                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1828                        evt_struct);
1829                 return;
1830         }
1831
1832         if (atomic_read(&evt_struct->free)) {
1833                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1834                         evt_struct);
1835                 return;
1836         }
1837
1838         if (crq->format == VIOSRP_SRP_FORMAT)
1839                 atomic_add(be32_to_cpu(evt_struct->xfer_iu->srp.rsp.req_lim_delta),
1840                            &hostdata->request_limit);
1841
1842         del_timer(&evt_struct->timer);
1843
1844         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1845                 evt_struct->cmnd->result = DID_ERROR << 16;
1846         if (evt_struct->done)
1847                 evt_struct->done(evt_struct);
1848         else
1849                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1850
1851         /*
1852          * Lock the host_lock before messing with these structures, since we
1853          * are running in a task context
1854          */
1855         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1856         list_del(&evt_struct->list);
1857         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1858         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1859 }
1860
1861 /**
1862  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1863  * @sdev:       struct scsi_device device to configure
1864  *
1865  * Enable allow_restart for a device if it is a disk.  Adjust the
1866  * queue_depth here also as is required by the documentation for
1867  * struct scsi_host_template.
1868  */
1869 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1870 {
1871         struct Scsi_Host *shost = sdev->host;
1872         unsigned long lock_flags = 0;
1873
1874         spin_lock_irqsave(shost->host_lock, lock_flags);
1875         if (sdev->type == TYPE_DISK) {
1876                 sdev->allow_restart = 1;
1877                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1878         }
1879         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1880         return 0;
1881 }
1882
1883 /**
1884  * ibmvscsi_change_queue_depth - Change the device's queue depth
1885  * @sdev:       scsi device struct
1886  * @qdepth:     depth to set
1887  *
1888  * Return value:
1889  *      actual depth set
1890  **/
1891 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1892 {
1893         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1894                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1895         return scsi_change_queue_depth(sdev, qdepth);
1896 }
1897
1898 /* ------------------------------------------------------------
1899  * sysfs attributes
1900  */
1901 static ssize_t show_host_vhost_loc(struct device *dev,
1902                                    struct device_attribute *attr, char *buf)
1903 {
1904         struct Scsi_Host *shost = class_to_shost(dev);
1905         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1906         int len;
1907
1908         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1909                        hostdata->caps.loc);
1910         return len;
1911 }
1912
1913 static struct device_attribute ibmvscsi_host_vhost_loc = {
1914         .attr = {
1915                  .name = "vhost_loc",
1916                  .mode = S_IRUGO,
1917                  },
1918         .show = show_host_vhost_loc,
1919 };
1920
1921 static ssize_t show_host_vhost_name(struct device *dev,
1922                                     struct device_attribute *attr, char *buf)
1923 {
1924         struct Scsi_Host *shost = class_to_shost(dev);
1925         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1926         int len;
1927
1928         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1929                        hostdata->caps.name);
1930         return len;
1931 }
1932
1933 static struct device_attribute ibmvscsi_host_vhost_name = {
1934         .attr = {
1935                  .name = "vhost_name",
1936                  .mode = S_IRUGO,
1937                  },
1938         .show = show_host_vhost_name,
1939 };
1940
1941 static ssize_t show_host_srp_version(struct device *dev,
1942                                      struct device_attribute *attr, char *buf)
1943 {
1944         struct Scsi_Host *shost = class_to_shost(dev);
1945         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1946         int len;
1947
1948         len = snprintf(buf, PAGE_SIZE, "%s\n",
1949                        hostdata->madapter_info.srp_version);
1950         return len;
1951 }
1952
1953 static struct device_attribute ibmvscsi_host_srp_version = {
1954         .attr = {
1955                  .name = "srp_version",
1956                  .mode = S_IRUGO,
1957                  },
1958         .show = show_host_srp_version,
1959 };
1960
1961 static ssize_t show_host_partition_name(struct device *dev,
1962                                         struct device_attribute *attr,
1963                                         char *buf)
1964 {
1965         struct Scsi_Host *shost = class_to_shost(dev);
1966         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1967         int len;
1968
1969         len = snprintf(buf, PAGE_SIZE, "%s\n",
1970                        hostdata->madapter_info.partition_name);
1971         return len;
1972 }
1973
1974 static struct device_attribute ibmvscsi_host_partition_name = {
1975         .attr = {
1976                  .name = "partition_name",
1977                  .mode = S_IRUGO,
1978                  },
1979         .show = show_host_partition_name,
1980 };
1981
1982 static ssize_t show_host_partition_number(struct device *dev,
1983                                           struct device_attribute *attr,
1984                                           char *buf)
1985 {
1986         struct Scsi_Host *shost = class_to_shost(dev);
1987         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1988         int len;
1989
1990         len = snprintf(buf, PAGE_SIZE, "%d\n",
1991                        be32_to_cpu(hostdata->madapter_info.partition_number));
1992         return len;
1993 }
1994
1995 static struct device_attribute ibmvscsi_host_partition_number = {
1996         .attr = {
1997                  .name = "partition_number",
1998                  .mode = S_IRUGO,
1999                  },
2000         .show = show_host_partition_number,
2001 };
2002
2003 static ssize_t show_host_mad_version(struct device *dev,
2004                                      struct device_attribute *attr, char *buf)
2005 {
2006         struct Scsi_Host *shost = class_to_shost(dev);
2007         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2008         int len;
2009
2010         len = snprintf(buf, PAGE_SIZE, "%d\n",
2011                        be32_to_cpu(hostdata->madapter_info.mad_version));
2012         return len;
2013 }
2014
2015 static struct device_attribute ibmvscsi_host_mad_version = {
2016         .attr = {
2017                  .name = "mad_version",
2018                  .mode = S_IRUGO,
2019                  },
2020         .show = show_host_mad_version,
2021 };
2022
2023 static ssize_t show_host_os_type(struct device *dev,
2024                                  struct device_attribute *attr, char *buf)
2025 {
2026         struct Scsi_Host *shost = class_to_shost(dev);
2027         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2028         int len;
2029
2030         len = snprintf(buf, PAGE_SIZE, "%d\n",
2031                        be32_to_cpu(hostdata->madapter_info.os_type));
2032         return len;
2033 }
2034
2035 static struct device_attribute ibmvscsi_host_os_type = {
2036         .attr = {
2037                  .name = "os_type",
2038                  .mode = S_IRUGO,
2039                  },
2040         .show = show_host_os_type,
2041 };
2042
2043 static ssize_t show_host_config(struct device *dev,
2044                                 struct device_attribute *attr, char *buf)
2045 {
2046         return 0;
2047 }
2048
2049 static struct device_attribute ibmvscsi_host_config = {
2050         .attr = {
2051                 .name = "config",
2052                 .mode = S_IRUGO,
2053                 },
2054         .show = show_host_config,
2055 };
2056
2057 static int ibmvscsi_host_reset(struct Scsi_Host *shost, int reset_type)
2058 {
2059         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
2060
2061         dev_info(hostdata->dev, "Initiating adapter reset!\n");
2062         ibmvscsi_reset_host(hostdata);
2063
2064         return 0;
2065 }
2066
2067 static struct device_attribute *ibmvscsi_attrs[] = {
2068         &ibmvscsi_host_vhost_loc,
2069         &ibmvscsi_host_vhost_name,
2070         &ibmvscsi_host_srp_version,
2071         &ibmvscsi_host_partition_name,
2072         &ibmvscsi_host_partition_number,
2073         &ibmvscsi_host_mad_version,
2074         &ibmvscsi_host_os_type,
2075         &ibmvscsi_host_config,
2076         NULL
2077 };
2078
2079 /* ------------------------------------------------------------
2080  * SCSI driver registration
2081  */
2082 static struct scsi_host_template driver_template = {
2083         .module = THIS_MODULE,
2084         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
2085         .proc_name = "ibmvscsi",
2086         .queuecommand = ibmvscsi_queuecommand,
2087         .eh_timed_out = srp_timed_out,
2088         .eh_abort_handler = ibmvscsi_eh_abort_handler,
2089         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
2090         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
2091         .slave_configure = ibmvscsi_slave_configure,
2092         .change_queue_depth = ibmvscsi_change_queue_depth,
2093         .host_reset = ibmvscsi_host_reset,
2094         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
2095         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
2096         .this_id = -1,
2097         .sg_tablesize = SG_ALL,
2098         .shost_attrs = ibmvscsi_attrs,
2099 };
2100
2101 /**
2102  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
2103  *
2104  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
2105  *
2106  * Return value:
2107  *      Number of bytes of IO data the driver will need to perform well.
2108  */
2109 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
2110 {
2111         /* iu_storage data allocated in initialize_event_pool */
2112         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
2113
2114         /* add io space for sg data */
2115         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
2116                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
2117
2118         return desired_io;
2119 }
2120
2121 static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata)
2122 {
2123         unsigned long flags;
2124         int rc;
2125         char *action = "reset";
2126
2127         spin_lock_irqsave(hostdata->host->host_lock, flags);
2128         switch (hostdata->action) {
2129         case IBMVSCSI_HOST_ACTION_UNBLOCK:
2130                 rc = 0;
2131                 break;
2132         case IBMVSCSI_HOST_ACTION_RESET:
2133                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
2134                 rc = ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata);
2135                 spin_lock_irqsave(hostdata->host->host_lock, flags);
2136                 if (!rc)
2137                         rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
2138                 vio_enable_interrupts(to_vio_dev(hostdata->dev));
2139                 break;
2140         case IBMVSCSI_HOST_ACTION_REENABLE:
2141                 action = "enable";
2142                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
2143                 rc = ibmvscsi_reenable_crq_queue(&hostdata->queue, hostdata);
2144                 spin_lock_irqsave(hostdata->host->host_lock, flags);
2145                 if (!rc)
2146                         rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
2147                 break;
2148         case IBMVSCSI_HOST_ACTION_NONE:
2149         default:
2150                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
2151                 return;
2152         }
2153
2154         hostdata->action = IBMVSCSI_HOST_ACTION_NONE;
2155         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
2156
2157         if (rc) {
2158                 ibmvscsi_set_request_limit(hostdata, -1);
2159                 dev_err(hostdata->dev, "error after %s\n", action);
2160         }
2161
2162         scsi_unblock_requests(hostdata->host);
2163 }
2164
2165 static int __ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
2166 {
2167         if (kthread_should_stop())
2168                 return 1;
2169         switch (hostdata->action) {
2170         case IBMVSCSI_HOST_ACTION_NONE:
2171                 return 0;
2172         case IBMVSCSI_HOST_ACTION_RESET:
2173         case IBMVSCSI_HOST_ACTION_REENABLE:
2174         case IBMVSCSI_HOST_ACTION_UNBLOCK:
2175         default:
2176                 break;
2177         }
2178
2179         return 1;
2180 }
2181
2182 static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
2183 {
2184         unsigned long flags;
2185         int rc;
2186
2187         spin_lock_irqsave(hostdata->host->host_lock, flags);
2188         rc = __ibmvscsi_work_to_do(hostdata);
2189         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
2190
2191         return rc;
2192 }
2193
2194 static int ibmvscsi_work(void *data)
2195 {
2196         struct ibmvscsi_host_data *hostdata = data;
2197         int rc;
2198
2199         set_user_nice(current, MIN_NICE);
2200
2201         while (1) {
2202                 rc = wait_event_interruptible(hostdata->work_wait_q,
2203                                               ibmvscsi_work_to_do(hostdata));
2204
2205                 BUG_ON(rc);
2206
2207                 if (kthread_should_stop())
2208                         break;
2209
2210                 ibmvscsi_do_work(hostdata);
2211         }
2212
2213         return 0;
2214 }
2215
2216 /*
2217  * Called by bus code for each adapter
2218  */
2219 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
2220 {
2221         struct ibmvscsi_host_data *hostdata;
2222         struct Scsi_Host *host;
2223         struct device *dev = &vdev->dev;
2224         struct srp_rport_identifiers ids;
2225         struct srp_rport *rport;
2226         unsigned long wait_switch = 0;
2227         int rc;
2228
2229         dev_set_drvdata(&vdev->dev, NULL);
2230
2231         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
2232         if (!host) {
2233                 dev_err(&vdev->dev, "couldn't allocate host data\n");
2234                 goto scsi_host_alloc_failed;
2235         }
2236
2237         host->transportt = ibmvscsi_transport_template;
2238         hostdata = shost_priv(host);
2239         memset(hostdata, 0x00, sizeof(*hostdata));
2240         INIT_LIST_HEAD(&hostdata->sent);
2241         init_waitqueue_head(&hostdata->work_wait_q);
2242         hostdata->host = host;
2243         hostdata->dev = dev;
2244         ibmvscsi_set_request_limit(hostdata, -1);
2245         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
2246
2247         if (map_persist_bufs(hostdata)) {
2248                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
2249                 goto persist_bufs_failed;
2250         }
2251
2252         hostdata->work_thread = kthread_run(ibmvscsi_work, hostdata, "%s_%d",
2253                                             "ibmvscsi", host->host_no);
2254
2255         if (IS_ERR(hostdata->work_thread)) {
2256                 dev_err(&vdev->dev, "couldn't initialize kthread. rc=%ld\n",
2257                         PTR_ERR(hostdata->work_thread));
2258                 goto init_crq_failed;
2259         }
2260
2261         rc = ibmvscsi_init_crq_queue(&hostdata->queue, hostdata, max_events);
2262         if (rc != 0 && rc != H_RESOURCE) {
2263                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
2264                 goto kill_kthread;
2265         }
2266         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
2267                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
2268                 goto init_pool_failed;
2269         }
2270
2271         host->max_lun = IBMVSCSI_MAX_LUN;
2272         host->max_id = max_id;
2273         host->max_channel = max_channel;
2274         host->max_cmd_len = 16;
2275
2276         dev_info(dev,
2277                  "Maximum ID: %d Maximum LUN: %llu Maximum Channel: %d\n",
2278                  host->max_id, host->max_lun, host->max_channel);
2279
2280         if (scsi_add_host(hostdata->host, hostdata->dev))
2281                 goto add_host_failed;
2282
2283         /* we don't have a proper target_port_id so let's use the fake one */
2284         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
2285                sizeof(ids.port_id));
2286         ids.roles = SRP_RPORT_ROLE_TARGET;
2287         rport = srp_rport_add(host, &ids);
2288         if (IS_ERR(rport))
2289                 goto add_srp_port_failed;
2290
2291         /* Try to send an initialization message.  Note that this is allowed
2292          * to fail if the other end is not acive.  In that case we don't
2293          * want to scan
2294          */
2295         if (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0) == 0
2296             || rc == H_RESOURCE) {
2297                 /*
2298                  * Wait around max init_timeout secs for the adapter to finish
2299                  * initializing. When we are done initializing, we will have a
2300                  * valid request_limit.  We don't want Linux scanning before
2301                  * we are ready.
2302                  */
2303                 for (wait_switch = jiffies + (init_timeout * HZ);
2304                      time_before(jiffies, wait_switch) &&
2305                      atomic_read(&hostdata->request_limit) < 2;) {
2306
2307                         msleep(10);
2308                 }
2309
2310                 /* if we now have a valid request_limit, initiate a scan */
2311                 if (atomic_read(&hostdata->request_limit) > 0)
2312                         scsi_scan_host(host);
2313         }
2314
2315         dev_set_drvdata(&vdev->dev, hostdata);
2316         spin_lock(&ibmvscsi_driver_lock);
2317         list_add_tail(&hostdata->host_list, &ibmvscsi_head);
2318         spin_unlock(&ibmvscsi_driver_lock);
2319         return 0;
2320
2321       add_srp_port_failed:
2322         scsi_remove_host(hostdata->host);
2323       add_host_failed:
2324         release_event_pool(&hostdata->pool, hostdata);
2325       init_pool_failed:
2326         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata, max_events);
2327       kill_kthread:
2328       kthread_stop(hostdata->work_thread);
2329       init_crq_failed:
2330         unmap_persist_bufs(hostdata);
2331       persist_bufs_failed:
2332         scsi_host_put(host);
2333       scsi_host_alloc_failed:
2334         return -1;
2335 }
2336
2337 static void ibmvscsi_remove(struct vio_dev *vdev)
2338 {
2339         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
2340
2341         srp_remove_host(hostdata->host);
2342         scsi_remove_host(hostdata->host);
2343
2344         purge_requests(hostdata, DID_ERROR);
2345         release_event_pool(&hostdata->pool, hostdata);
2346
2347         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
2348                                         max_events);
2349
2350         kthread_stop(hostdata->work_thread);
2351         unmap_persist_bufs(hostdata);
2352
2353         spin_lock(&ibmvscsi_driver_lock);
2354         list_del(&hostdata->host_list);
2355         spin_unlock(&ibmvscsi_driver_lock);
2356
2357         scsi_host_put(hostdata->host);
2358 }
2359
2360 /**
2361  * ibmvscsi_resume: Resume from suspend
2362  * @dev:        device struct
2363  *
2364  * We may have lost an interrupt across suspend/resume, so kick the
2365  * interrupt handler
2366  */
2367 static int ibmvscsi_resume(struct device *dev)
2368 {
2369         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
2370         vio_disable_interrupts(to_vio_dev(hostdata->dev));
2371         tasklet_schedule(&hostdata->srp_task);
2372
2373         return 0;
2374 }
2375
2376 /*
2377  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we 
2378  * support.
2379  */
2380 static const struct vio_device_id ibmvscsi_device_table[] = {
2381         {"vscsi", "IBM,v-scsi"},
2382         { "", "" }
2383 };
2384 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
2385
2386 static const struct dev_pm_ops ibmvscsi_pm_ops = {
2387         .resume = ibmvscsi_resume
2388 };
2389
2390 static struct vio_driver ibmvscsi_driver = {
2391         .id_table = ibmvscsi_device_table,
2392         .probe = ibmvscsi_probe,
2393         .remove = ibmvscsi_remove,
2394         .get_desired_dma = ibmvscsi_get_desired_dma,
2395         .name = "ibmvscsi",
2396         .pm = &ibmvscsi_pm_ops,
2397 };
2398
2399 static struct srp_function_template ibmvscsi_transport_functions = {
2400 };
2401
2402 static int __init ibmvscsi_module_init(void)
2403 {
2404         int ret;
2405
2406         /* Ensure we have two requests to do error recovery */
2407         driver_template.can_queue = max_requests;
2408         max_events = max_requests + 2;
2409
2410         if (!firmware_has_feature(FW_FEATURE_VIO))
2411                 return -ENODEV;
2412
2413         ibmvscsi_transport_template =
2414                 srp_attach_transport(&ibmvscsi_transport_functions);
2415         if (!ibmvscsi_transport_template)
2416                 return -ENOMEM;
2417
2418         ret = vio_register_driver(&ibmvscsi_driver);
2419         if (ret)
2420                 srp_release_transport(ibmvscsi_transport_template);
2421         return ret;
2422 }
2423
2424 static void __exit ibmvscsi_module_exit(void)
2425 {
2426         vio_unregister_driver(&ibmvscsi_driver);
2427         srp_release_transport(ibmvscsi_transport_template);
2428 }
2429
2430 module_init(ibmvscsi_module_init);
2431 module_exit(ibmvscsi_module_exit);