Merge branch 'misc' into release
[linux-2.6] / drivers / scsi / ibmvscsi / ibmvscsi.c
1 /* ------------------------------------------------------------
2  * ibmvscsi.c
3  * (C) Copyright IBM Corporation 1994, 2004
4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
5  *          Santiago Leon (santil@us.ibm.com)
6  *          Dave Boutcher (sleddog@us.ibm.com)
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
21  * USA
22  *
23  * ------------------------------------------------------------
24  * Emulation of a SCSI host adapter for Virtual I/O devices
25  *
26  * This driver supports the SCSI adapter implemented by the IBM
27  * Power5 firmware.  That SCSI adapter is not a physical adapter,
28  * but allows Linux SCSI peripheral drivers to directly
29  * access devices in another logical partition on the physical system.
30  *
31  * The virtual adapter(s) are present in the open firmware device
32  * tree just like real adapters.
33  *
34  * One of the capabilities provided on these systems is the ability
35  * to DMA between partitions.  The architecture states that for VSCSI,
36  * the server side is allowed to DMA to and from the client.  The client
37  * is never trusted to DMA to or from the server directly.
38  *
39  * Messages are sent between partitions on a "Command/Response Queue" 
40  * (CRQ), which is just a buffer of 16 byte entries in the receiver's 
41  * Senders cannot access the buffer directly, but send messages by
42  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
43  * puts the message in the next 16 byte space in round-robbin fashion,
44  * turns on the high order bit of the message (the valid bit), and 
45  * generates an interrupt to the receiver (if interrupts are turned on.) 
46  * The receiver just turns off the valid bit when they have copied out
47  * the message.
48  *
49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
50  * (IU) (as defined in the T10 standard available at www.t10.org), gets 
51  * a DMA address for the message, and sends it to the server as the
52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
53  * including doing any additional data transfers.  When it is done, it
54  * DMAs the SRP response back to the same address as the request came from,
55  * and sends a CRQ message back to inform the client that the request has
56  * completed.
57  *
58  * Note that some of the underlying infrastructure is different between
59  * machines conforming to the "RS/6000 Platform Architecture" (RPA) and
60  * the older iSeries hypervisor models.  To support both, some low level
61  * routines have been broken out into rpa_vscsi.c and iseries_vscsi.c.
62  * The Makefile should pick one, not two, not zero, of these.
63  *
64  * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor
65  * interfaces.  It would be really nice to abstract this above an RDMA
66  * layer.
67  */
68
69 #include <linux/module.h>
70 #include <linux/moduleparam.h>
71 #include <linux/dma-mapping.h>
72 #include <linux/delay.h>
73 #include <asm/firmware.h>
74 #include <asm/vio.h>
75 #include <asm/firmware.h>
76 #include <scsi/scsi.h>
77 #include <scsi/scsi_cmnd.h>
78 #include <scsi/scsi_host.h>
79 #include <scsi/scsi_device.h>
80 #include <scsi/scsi_transport_srp.h>
81 #include "ibmvscsi.h"
82
83 /* The values below are somewhat arbitrary default values, but 
84  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
85  * Note that there are 3 bits of channel value, 6 bits of id, and
86  * 5 bits of LUN.
87  */
88 static int max_id = 64;
89 static int max_channel = 3;
90 static int init_timeout = 5;
91 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
92 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
93
94 static struct scsi_transport_template *ibmvscsi_transport_template;
95
96 #define IBMVSCSI_VERSION "1.5.8"
97
98 static struct ibmvscsi_ops *ibmvscsi_ops;
99
100 MODULE_DESCRIPTION("IBM Virtual SCSI");
101 MODULE_AUTHOR("Dave Boutcher");
102 MODULE_LICENSE("GPL");
103 MODULE_VERSION(IBMVSCSI_VERSION);
104
105 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
106 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
107 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
108 MODULE_PARM_DESC(max_channel, "Largest channel value");
109 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
110 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
111 module_param_named(max_requests, max_requests, int, S_IRUGO);
112 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
113
114 /* ------------------------------------------------------------
115  * Routines for the event pool and event structs
116  */
117 /**
118  * initialize_event_pool: - Allocates and initializes the event pool for a host
119  * @pool:       event_pool to be initialized
120  * @size:       Number of events in pool
121  * @hostdata:   ibmvscsi_host_data who owns the event pool
122  *
123  * Returns zero on success.
124 */
125 static int initialize_event_pool(struct event_pool *pool,
126                                  int size, struct ibmvscsi_host_data *hostdata)
127 {
128         int i;
129
130         pool->size = size;
131         pool->next = 0;
132         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
133         if (!pool->events)
134                 return -ENOMEM;
135
136         pool->iu_storage =
137             dma_alloc_coherent(hostdata->dev,
138                                pool->size * sizeof(*pool->iu_storage),
139                                &pool->iu_token, 0);
140         if (!pool->iu_storage) {
141                 kfree(pool->events);
142                 return -ENOMEM;
143         }
144
145         for (i = 0; i < pool->size; ++i) {
146                 struct srp_event_struct *evt = &pool->events[i];
147                 memset(&evt->crq, 0x00, sizeof(evt->crq));
148                 atomic_set(&evt->free, 1);
149                 evt->crq.valid = 0x80;
150                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
151                 evt->crq.IU_data_ptr = pool->iu_token + 
152                         sizeof(*evt->xfer_iu) * i;
153                 evt->xfer_iu = pool->iu_storage + i;
154                 evt->hostdata = hostdata;
155                 evt->ext_list = NULL;
156                 evt->ext_list_token = 0;
157         }
158
159         return 0;
160 }
161
162 /**
163  * release_event_pool: - Frees memory of an event pool of a host
164  * @pool:       event_pool to be released
165  * @hostdata:   ibmvscsi_host_data who owns the even pool
166  *
167  * Returns zero on success.
168 */
169 static void release_event_pool(struct event_pool *pool,
170                                struct ibmvscsi_host_data *hostdata)
171 {
172         int i, in_use = 0;
173         for (i = 0; i < pool->size; ++i) {
174                 if (atomic_read(&pool->events[i].free) != 1)
175                         ++in_use;
176                 if (pool->events[i].ext_list) {
177                         dma_free_coherent(hostdata->dev,
178                                   SG_ALL * sizeof(struct srp_direct_buf),
179                                   pool->events[i].ext_list,
180                                   pool->events[i].ext_list_token);
181                 }
182         }
183         if (in_use)
184                 dev_warn(hostdata->dev, "releasing event pool with %d "
185                          "events still in use?\n", in_use);
186         kfree(pool->events);
187         dma_free_coherent(hostdata->dev,
188                           pool->size * sizeof(*pool->iu_storage),
189                           pool->iu_storage, pool->iu_token);
190 }
191
192 /**
193  * valid_event_struct: - Determines if event is valid.
194  * @pool:       event_pool that contains the event
195  * @evt:        srp_event_struct to be checked for validity
196  *
197  * Returns zero if event is invalid, one otherwise.
198 */
199 static int valid_event_struct(struct event_pool *pool,
200                                 struct srp_event_struct *evt)
201 {
202         int index = evt - pool->events;
203         if (index < 0 || index >= pool->size)   /* outside of bounds */
204                 return 0;
205         if (evt != pool->events + index)        /* unaligned */
206                 return 0;
207         return 1;
208 }
209
210 /**
211  * ibmvscsi_free-event_struct: - Changes status of event to "free"
212  * @pool:       event_pool that contains the event
213  * @evt:        srp_event_struct to be modified
214  *
215 */
216 static void free_event_struct(struct event_pool *pool,
217                                        struct srp_event_struct *evt)
218 {
219         if (!valid_event_struct(pool, evt)) {
220                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
221                         "(not in pool %p)\n", evt, pool->events);
222                 return;
223         }
224         if (atomic_inc_return(&evt->free) != 1) {
225                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
226                         "which is not in use!\n", evt);
227                 return;
228         }
229 }
230
231 /**
232  * get_evt_struct: - Gets the next free event in pool
233  * @pool:       event_pool that contains the events to be searched
234  *
235  * Returns the next event in "free" state, and NULL if none are free.
236  * Note that no synchronization is done here, we assume the host_lock
237  * will syncrhonze things.
238 */
239 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
240 {
241         int i;
242         int poolsize = pool->size;
243         int offset = pool->next;
244
245         for (i = 0; i < poolsize; i++) {
246                 offset = (offset + 1) % poolsize;
247                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
248                         pool->next = offset;
249                         return &pool->events[offset];
250                 }
251         }
252
253         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
254         return NULL;
255 }
256
257 /**
258  * init_event_struct: Initialize fields in an event struct that are always 
259  *                    required.
260  * @evt:        The event
261  * @done:       Routine to call when the event is responded to
262  * @format:     SRP or MAD format
263  * @timeout:    timeout value set in the CRQ
264  */
265 static void init_event_struct(struct srp_event_struct *evt_struct,
266                               void (*done) (struct srp_event_struct *),
267                               u8 format,
268                               int timeout)
269 {
270         evt_struct->cmnd = NULL;
271         evt_struct->cmnd_done = NULL;
272         evt_struct->sync_srp = NULL;
273         evt_struct->crq.format = format;
274         evt_struct->crq.timeout = timeout;
275         evt_struct->done = done;
276 }
277
278 /* ------------------------------------------------------------
279  * Routines for receiving SCSI responses from the hosting partition
280  */
281
282 /**
283  * set_srp_direction: Set the fields in the srp related to data
284  *     direction and number of buffers based on the direction in
285  *     the scsi_cmnd and the number of buffers
286  */
287 static void set_srp_direction(struct scsi_cmnd *cmd,
288                               struct srp_cmd *srp_cmd, 
289                               int numbuf)
290 {
291         u8 fmt;
292
293         if (numbuf == 0)
294                 return;
295         
296         if (numbuf == 1)
297                 fmt = SRP_DATA_DESC_DIRECT;
298         else {
299                 fmt = SRP_DATA_DESC_INDIRECT;
300                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
301
302                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
303                         srp_cmd->data_out_desc_cnt = numbuf;
304                 else
305                         srp_cmd->data_in_desc_cnt = numbuf;
306         }
307
308         if (cmd->sc_data_direction == DMA_TO_DEVICE)
309                 srp_cmd->buf_fmt = fmt << 4;
310         else
311                 srp_cmd->buf_fmt = fmt;
312 }
313
314 static void unmap_sg_list(int num_entries,
315                 struct device *dev,
316                 struct srp_direct_buf *md)
317 {
318         int i;
319
320         for (i = 0; i < num_entries; ++i)
321                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
322 }
323
324 /**
325  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
326  * @cmd:        srp_cmd whose additional_data member will be unmapped
327  * @dev:        device for which the memory is mapped
328  *
329 */
330 static void unmap_cmd_data(struct srp_cmd *cmd,
331                            struct srp_event_struct *evt_struct,
332                            struct device *dev)
333 {
334         u8 out_fmt, in_fmt;
335
336         out_fmt = cmd->buf_fmt >> 4;
337         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
338
339         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
340                 return;
341         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
342                  in_fmt == SRP_DATA_DESC_DIRECT) {
343                 struct srp_direct_buf *data =
344                         (struct srp_direct_buf *) cmd->add_data;
345                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
346         } else {
347                 struct srp_indirect_buf *indirect =
348                         (struct srp_indirect_buf *) cmd->add_data;
349                 int num_mapped = indirect->table_desc.len /
350                         sizeof(struct srp_direct_buf);
351
352                 if (num_mapped <= MAX_INDIRECT_BUFS) {
353                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
354                         return;
355                 }
356
357                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
358         }
359 }
360
361 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
362                        struct srp_direct_buf *md)
363 {
364         int i;
365         struct scatterlist *sg;
366         u64 total_length = 0;
367
368         scsi_for_each_sg(cmd, sg, nseg, i) {
369                 struct srp_direct_buf *descr = md + i;
370                 descr->va = sg_dma_address(sg);
371                 descr->len = sg_dma_len(sg);
372                 descr->key = 0;
373                 total_length += sg_dma_len(sg);
374         }
375         return total_length;
376 }
377
378 /**
379  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
380  * @cmd:        Scsi_Cmnd with the scatterlist
381  * @srp_cmd:    srp_cmd that contains the memory descriptor
382  * @dev:        device for which to map dma memory
383  *
384  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
385  * Returns 1 on success.
386 */
387 static int map_sg_data(struct scsi_cmnd *cmd,
388                        struct srp_event_struct *evt_struct,
389                        struct srp_cmd *srp_cmd, struct device *dev)
390 {
391
392         int sg_mapped;
393         u64 total_length = 0;
394         struct srp_direct_buf *data =
395                 (struct srp_direct_buf *) srp_cmd->add_data;
396         struct srp_indirect_buf *indirect =
397                 (struct srp_indirect_buf *) data;
398
399         sg_mapped = scsi_dma_map(cmd);
400         if (!sg_mapped)
401                 return 1;
402         else if (sg_mapped < 0)
403                 return 0;
404
405         set_srp_direction(cmd, srp_cmd, sg_mapped);
406
407         /* special case; we can use a single direct descriptor */
408         if (sg_mapped == 1) {
409                 map_sg_list(cmd, sg_mapped, data);
410                 return 1;
411         }
412
413         indirect->table_desc.va = 0;
414         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
415         indirect->table_desc.key = 0;
416
417         if (sg_mapped <= MAX_INDIRECT_BUFS) {
418                 total_length = map_sg_list(cmd, sg_mapped,
419                                            &indirect->desc_list[0]);
420                 indirect->len = total_length;
421                 return 1;
422         }
423
424         /* get indirect table */
425         if (!evt_struct->ext_list) {
426                 evt_struct->ext_list = (struct srp_direct_buf *)
427                         dma_alloc_coherent(dev,
428                                            SG_ALL * sizeof(struct srp_direct_buf),
429                                            &evt_struct->ext_list_token, 0);
430                 if (!evt_struct->ext_list) {
431                         if (!firmware_has_feature(FW_FEATURE_CMO))
432                                 sdev_printk(KERN_ERR, cmd->device,
433                                             "Can't allocate memory "
434                                             "for indirect table\n");
435                         return 0;
436                 }
437         }
438
439         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
440
441         indirect->len = total_length;
442         indirect->table_desc.va = evt_struct->ext_list_token;
443         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
444         memcpy(indirect->desc_list, evt_struct->ext_list,
445                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
446         return 1;
447 }
448
449 /**
450  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
451  * @cmd:        struct scsi_cmnd with the memory to be mapped
452  * @srp_cmd:    srp_cmd that contains the memory descriptor
453  * @dev:        dma device for which to map dma memory
454  *
455  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds 
456  * Returns 1 on success.
457 */
458 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
459                                 struct srp_event_struct *evt_struct,
460                                 struct srp_cmd *srp_cmd, struct device *dev)
461 {
462         switch (cmd->sc_data_direction) {
463         case DMA_FROM_DEVICE:
464         case DMA_TO_DEVICE:
465                 break;
466         case DMA_NONE:
467                 return 1;
468         case DMA_BIDIRECTIONAL:
469                 sdev_printk(KERN_ERR, cmd->device,
470                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
471                 return 0;
472         default:
473                 sdev_printk(KERN_ERR, cmd->device,
474                             "Unknown data direction 0x%02x; can't map!\n",
475                             cmd->sc_data_direction);
476                 return 0;
477         }
478
479         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
480 }
481
482 /**
483  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
484  * @hostdata:    the adapter
485  */
486 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
487 {
488         struct srp_event_struct *tmp_evt, *pos;
489         unsigned long flags;
490
491         spin_lock_irqsave(hostdata->host->host_lock, flags);
492         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
493                 list_del(&tmp_evt->list);
494                 del_timer(&tmp_evt->timer);
495                 if (tmp_evt->cmnd) {
496                         tmp_evt->cmnd->result = (error_code << 16);
497                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
498                                        tmp_evt,
499                                        tmp_evt->hostdata->dev);
500                         if (tmp_evt->cmnd_done)
501                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
502                 } else if (tmp_evt->done)
503                         tmp_evt->done(tmp_evt);
504                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
505         }
506         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
507 }
508
509 /**
510  * ibmvscsi_reset_host - Reset the connection to the server
511  * @hostdata:   struct ibmvscsi_host_data to reset
512 */
513 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
514 {
515         scsi_block_requests(hostdata->host);
516         atomic_set(&hostdata->request_limit, 0);
517
518         purge_requests(hostdata, DID_ERROR);
519         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata)) ||
520             (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0)) ||
521             (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) {
522                 atomic_set(&hostdata->request_limit, -1);
523                 dev_err(hostdata->dev, "error after reset\n");
524         }
525
526         scsi_unblock_requests(hostdata->host);
527 }
528
529 /**
530  * ibmvscsi_timeout - Internal command timeout handler
531  * @evt_struct: struct srp_event_struct that timed out
532  *
533  * Called when an internally generated command times out
534 */
535 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
536 {
537         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
538
539         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
540                 evt_struct->iu.srp.cmd.opcode);
541
542         ibmvscsi_reset_host(hostdata);
543 }
544
545
546 /* ------------------------------------------------------------
547  * Routines for sending and receiving SRPs
548  */
549 /**
550  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
551  * @evt_struct: evt_struct to be sent
552  * @hostdata:   ibmvscsi_host_data of host
553  * @timeout:    timeout in seconds - 0 means do not time command
554  *
555  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
556  * Note that this routine assumes that host_lock is held for synchronization
557 */
558 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
559                                    struct ibmvscsi_host_data *hostdata,
560                                    unsigned long timeout)
561 {
562         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
563         int request_status = 0;
564         int rc;
565
566         /* If we have exhausted our request limit, just fail this request,
567          * unless it is for a reset or abort.
568          * Note that there are rare cases involving driver generated requests 
569          * (such as task management requests) that the mid layer may think we
570          * can handle more requests (can_queue) when we actually can't
571          */
572         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
573                 request_status =
574                         atomic_dec_if_positive(&hostdata->request_limit);
575                 /* If request limit was -1 when we started, it is now even
576                  * less than that
577                  */
578                 if (request_status < -1)
579                         goto send_error;
580                 /* Otherwise, we may have run out of requests. */
581                 /* If request limit was 0 when we started the adapter is in the
582                  * process of performing a login with the server adapter, or
583                  * we may have run out of requests.
584                  */
585                 else if (request_status == -1 &&
586                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
587                         goto send_busy;
588                 /* Abort and reset calls should make it through.
589                  * Nothing except abort and reset should use the last two
590                  * slots unless we had two or less to begin with.
591                  */
592                 else if (request_status < 2 &&
593                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
594                         /* In the case that we have less than two requests
595                          * available, check the server limit as a combination
596                          * of the request limit and the number of requests
597                          * in-flight (the size of the send list).  If the
598                          * server limit is greater than 2, return busy so
599                          * that the last two are reserved for reset and abort.
600                          */
601                         int server_limit = request_status;
602                         struct srp_event_struct *tmp_evt;
603
604                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
605                                 server_limit++;
606                         }
607
608                         if (server_limit > 2)
609                                 goto send_busy;
610                 }
611         }
612
613         /* Copy the IU into the transfer area */
614         *evt_struct->xfer_iu = evt_struct->iu;
615         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
616
617         /* Add this to the sent list.  We need to do this 
618          * before we actually send 
619          * in case it comes back REALLY fast
620          */
621         list_add_tail(&evt_struct->list, &hostdata->sent);
622
623         init_timer(&evt_struct->timer);
624         if (timeout) {
625                 evt_struct->timer.data = (unsigned long) evt_struct;
626                 evt_struct->timer.expires = jiffies + (timeout * HZ);
627                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
628                 add_timer(&evt_struct->timer);
629         }
630
631         if ((rc =
632              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
633                 list_del(&evt_struct->list);
634                 del_timer(&evt_struct->timer);
635
636                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
637                  * Firmware will send a CRQ with a transport event (0xFF) to
638                  * tell this client what has happened to the transport.  This
639                  * will be handled in ibmvscsi_handle_crq()
640                  */
641                 if (rc == H_CLOSED) {
642                         dev_warn(hostdata->dev, "send warning. "
643                                  "Receive queue closed, will retry.\n");
644                         goto send_busy;
645                 }
646                 dev_err(hostdata->dev, "send error %d\n", rc);
647                 atomic_inc(&hostdata->request_limit);
648                 goto send_error;
649         }
650
651         return 0;
652
653  send_busy:
654         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
655
656         free_event_struct(&hostdata->pool, evt_struct);
657         if (request_status != -1)
658                 atomic_inc(&hostdata->request_limit);
659         return SCSI_MLQUEUE_HOST_BUSY;
660
661  send_error:
662         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
663
664         if (evt_struct->cmnd != NULL) {
665                 evt_struct->cmnd->result = DID_ERROR << 16;
666                 evt_struct->cmnd_done(evt_struct->cmnd);
667         } else if (evt_struct->done)
668                 evt_struct->done(evt_struct);
669
670         free_event_struct(&hostdata->pool, evt_struct);
671         return 0;
672 }
673
674 /**
675  * handle_cmd_rsp: -  Handle responses from commands
676  * @evt_struct: srp_event_struct to be handled
677  *
678  * Used as a callback by when sending scsi cmds.
679  * Gets called by ibmvscsi_handle_crq()
680 */
681 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
682 {
683         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
684         struct scsi_cmnd *cmnd = evt_struct->cmnd;
685
686         if (unlikely(rsp->opcode != SRP_RSP)) {
687                 if (printk_ratelimit())
688                         dev_warn(evt_struct->hostdata->dev,
689                                  "bad SRP RSP type %d\n", rsp->opcode);
690         }
691         
692         if (cmnd) {
693                 cmnd->result |= rsp->status;
694                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
695                         memcpy(cmnd->sense_buffer,
696                                rsp->data,
697                                rsp->sense_data_len);
698                 unmap_cmd_data(&evt_struct->iu.srp.cmd, 
699                                evt_struct, 
700                                evt_struct->hostdata->dev);
701
702                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
703                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
704                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
705                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
706         }
707
708         if (evt_struct->cmnd_done)
709                 evt_struct->cmnd_done(cmnd);
710 }
711
712 /**
713  * lun_from_dev: - Returns the lun of the scsi device
714  * @dev:        struct scsi_device
715  *
716 */
717 static inline u16 lun_from_dev(struct scsi_device *dev)
718 {
719         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
720 }
721
722 /**
723  * ibmvscsi_queue: - The queuecommand function of the scsi template 
724  * @cmd:        struct scsi_cmnd to be executed
725  * @done:       Callback function to be called when cmd is completed
726 */
727 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
728                                  void (*done) (struct scsi_cmnd *))
729 {
730         struct srp_cmd *srp_cmd;
731         struct srp_event_struct *evt_struct;
732         struct srp_indirect_buf *indirect;
733         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
734         u16 lun = lun_from_dev(cmnd->device);
735         u8 out_fmt, in_fmt;
736
737         cmnd->result = (DID_OK << 16);
738         evt_struct = get_event_struct(&hostdata->pool);
739         if (!evt_struct)
740                 return SCSI_MLQUEUE_HOST_BUSY;
741
742         /* Set up the actual SRP IU */
743         srp_cmd = &evt_struct->iu.srp.cmd;
744         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
745         srp_cmd->opcode = SRP_CMD;
746         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
747         srp_cmd->lun = ((u64) lun) << 48;
748
749         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
750                 if (!firmware_has_feature(FW_FEATURE_CMO))
751                         sdev_printk(KERN_ERR, cmnd->device,
752                                     "couldn't convert cmd to srp_cmd\n");
753                 free_event_struct(&hostdata->pool, evt_struct);
754                 return SCSI_MLQUEUE_HOST_BUSY;
755         }
756
757         init_event_struct(evt_struct,
758                           handle_cmd_rsp,
759                           VIOSRP_SRP_FORMAT,
760                           cmnd->request->timeout/HZ);
761
762         evt_struct->cmnd = cmnd;
763         evt_struct->cmnd_done = done;
764
765         /* Fix up dma address of the buffer itself */
766         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
767         out_fmt = srp_cmd->buf_fmt >> 4;
768         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
769         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
770              out_fmt == SRP_DATA_DESC_INDIRECT) &&
771             indirect->table_desc.va == 0) {
772                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
773                         offsetof(struct srp_cmd, add_data) +
774                         offsetof(struct srp_indirect_buf, desc_list);
775         }
776
777         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
778 }
779
780 /* ------------------------------------------------------------
781  * Routines for driver initialization
782  */
783 /**
784  * adapter_info_rsp: - Handle response to MAD adapter info request
785  * @evt_struct: srp_event_struct with the response
786  *
787  * Used as a "done" callback by when sending adapter_info. Gets called
788  * by ibmvscsi_handle_crq()
789 */
790 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
791 {
792         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
793         dma_unmap_single(hostdata->dev,
794                          evt_struct->iu.mad.adapter_info.buffer,
795                          evt_struct->iu.mad.adapter_info.common.length,
796                          DMA_BIDIRECTIONAL);
797
798         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
799                 dev_err(hostdata->dev, "error %d getting adapter info\n",
800                         evt_struct->xfer_iu->mad.adapter_info.common.status);
801         } else {
802                 dev_info(hostdata->dev, "host srp version: %s, "
803                          "host partition %s (%d), OS %d, max io %u\n",
804                          hostdata->madapter_info.srp_version,
805                          hostdata->madapter_info.partition_name,
806                          hostdata->madapter_info.partition_number,
807                          hostdata->madapter_info.os_type,
808                          hostdata->madapter_info.port_max_txu[0]);
809                 
810                 if (hostdata->madapter_info.port_max_txu[0]) 
811                         hostdata->host->max_sectors = 
812                                 hostdata->madapter_info.port_max_txu[0] >> 9;
813                 
814                 if (hostdata->madapter_info.os_type == 3 &&
815                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
816                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
817                                 hostdata->madapter_info.srp_version);
818                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
819                                 MAX_INDIRECT_BUFS);
820                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
821                 }
822         }
823 }
824
825 /**
826  * send_mad_adapter_info: - Sends the mad adapter info request
827  *      and stores the result so it can be retrieved with
828  *      sysfs.  We COULD consider causing a failure if the
829  *      returned SRP version doesn't match ours.
830  * @hostdata:   ibmvscsi_host_data of host
831  * 
832  * Returns zero if successful.
833 */
834 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
835 {
836         struct viosrp_adapter_info *req;
837         struct srp_event_struct *evt_struct;
838         unsigned long flags;
839         dma_addr_t addr;
840
841         evt_struct = get_event_struct(&hostdata->pool);
842         if (!evt_struct) {
843                 dev_err(hostdata->dev,
844                         "couldn't allocate an event for ADAPTER_INFO_REQ!\n");
845                 return;
846         }
847
848         init_event_struct(evt_struct,
849                           adapter_info_rsp,
850                           VIOSRP_MAD_FORMAT,
851                           init_timeout);
852         
853         req = &evt_struct->iu.mad.adapter_info;
854         memset(req, 0x00, sizeof(*req));
855         
856         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
857         req->common.length = sizeof(hostdata->madapter_info);
858         req->buffer = addr = dma_map_single(hostdata->dev,
859                                             &hostdata->madapter_info,
860                                             sizeof(hostdata->madapter_info),
861                                             DMA_BIDIRECTIONAL);
862
863         if (dma_mapping_error(hostdata->dev, req->buffer)) {
864                 if (!firmware_has_feature(FW_FEATURE_CMO))
865                         dev_err(hostdata->dev,
866                                 "Unable to map request_buffer for "
867                                 "adapter_info!\n");
868                 free_event_struct(&hostdata->pool, evt_struct);
869                 return;
870         }
871         
872         spin_lock_irqsave(hostdata->host->host_lock, flags);
873         if (ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2)) {
874                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
875                 dma_unmap_single(hostdata->dev,
876                                  addr,
877                                  sizeof(hostdata->madapter_info),
878                                  DMA_BIDIRECTIONAL);
879         }
880         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
881 };
882
883 /**
884  * login_rsp: - Handle response to SRP login request
885  * @evt_struct: srp_event_struct with the response
886  *
887  * Used as a "done" callback by when sending srp_login. Gets called
888  * by ibmvscsi_handle_crq()
889 */
890 static void login_rsp(struct srp_event_struct *evt_struct)
891 {
892         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
893         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
894         case SRP_LOGIN_RSP:     /* it worked! */
895                 break;
896         case SRP_LOGIN_REJ:     /* refused! */
897                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
898                          evt_struct->xfer_iu->srp.login_rej.reason);
899                 /* Login failed.  */
900                 atomic_set(&hostdata->request_limit, -1);
901                 return;
902         default:
903                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
904                         evt_struct->xfer_iu->srp.login_rsp.opcode);
905                 /* Login failed.  */
906                 atomic_set(&hostdata->request_limit, -1);
907                 return;
908         }
909
910         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
911
912         if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta < 0)
913                 dev_err(hostdata->dev, "Invalid request_limit.\n");
914
915         /* Now we know what the real request-limit is.
916          * This value is set rather than added to request_limit because
917          * request_limit could have been set to -1 by this client.
918          */
919         atomic_set(&hostdata->request_limit,
920                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
921
922         /* If we had any pending I/Os, kick them */
923         scsi_unblock_requests(hostdata->host);
924
925         send_mad_adapter_info(hostdata);
926         return;
927 }
928
929 /**
930  * send_srp_login: - Sends the srp login
931  * @hostdata:   ibmvscsi_host_data of host
932  * 
933  * Returns zero if successful.
934 */
935 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
936 {
937         int rc;
938         unsigned long flags;
939         struct srp_login_req *login;
940         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
941         if (!evt_struct) {
942                 dev_err(hostdata->dev, "couldn't allocate an event for login req!\n");
943                 return FAILED;
944         }
945
946         init_event_struct(evt_struct,
947                           login_rsp,
948                           VIOSRP_SRP_FORMAT,
949                           init_timeout);
950
951         login = &evt_struct->iu.srp.login_req;
952         memset(login, 0x00, sizeof(struct srp_login_req));
953         login->opcode = SRP_LOGIN_REQ;
954         login->req_it_iu_len = sizeof(union srp_iu);
955         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
956         
957         spin_lock_irqsave(hostdata->host->host_lock, flags);
958         /* Start out with a request limit of 0, since this is negotiated in
959          * the login request we are just sending and login requests always
960          * get sent by the driver regardless of request_limit.
961          */
962         atomic_set(&hostdata->request_limit, 0);
963
964         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2);
965         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
966         dev_info(hostdata->dev, "sent SRP login\n");
967         return rc;
968 };
969
970 /**
971  * sync_completion: Signal that a synchronous command has completed
972  * Note that after returning from this call, the evt_struct is freed.
973  * the caller waiting on this completion shouldn't touch the evt_struct
974  * again.
975  */
976 static void sync_completion(struct srp_event_struct *evt_struct)
977 {
978         /* copy the response back */
979         if (evt_struct->sync_srp)
980                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
981         
982         complete(&evt_struct->comp);
983 }
984
985 /**
986  * ibmvscsi_abort: Abort a command...from scsi host template
987  * send this over to the server and wait synchronously for the response
988  */
989 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
990 {
991         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
992         struct srp_tsk_mgmt *tsk_mgmt;
993         struct srp_event_struct *evt;
994         struct srp_event_struct *tmp_evt, *found_evt;
995         union viosrp_iu srp_rsp;
996         int rsp_rc;
997         unsigned long flags;
998         u16 lun = lun_from_dev(cmd->device);
999         unsigned long wait_switch = 0;
1000
1001         /* First, find this command in our sent list so we can figure
1002          * out the correct tag
1003          */
1004         spin_lock_irqsave(hostdata->host->host_lock, flags);
1005         wait_switch = jiffies + (init_timeout * HZ);
1006         do {
1007                 found_evt = NULL;
1008                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1009                         if (tmp_evt->cmnd == cmd) {
1010                                 found_evt = tmp_evt;
1011                                 break;
1012                         }
1013                 }
1014
1015                 if (!found_evt) {
1016                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1017                         return SUCCESS;
1018                 }
1019
1020                 evt = get_event_struct(&hostdata->pool);
1021                 if (evt == NULL) {
1022                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1023                         sdev_printk(KERN_ERR, cmd->device,
1024                                 "failed to allocate abort event\n");
1025                         return FAILED;
1026                 }
1027         
1028                 init_event_struct(evt,
1029                                   sync_completion,
1030                                   VIOSRP_SRP_FORMAT,
1031                                   init_timeout);
1032
1033                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1034         
1035                 /* Set up an abort SRP command */
1036                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1037                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1038                 tsk_mgmt->lun = ((u64) lun) << 48;
1039                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1040                 tsk_mgmt->task_tag = (u64) found_evt;
1041
1042                 evt->sync_srp = &srp_rsp;
1043
1044                 init_completion(&evt->comp);
1045                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2);
1046
1047                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1048                         break;
1049
1050                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1051                 msleep(10);
1052                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1053         } while (time_before(jiffies, wait_switch));
1054
1055         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1056
1057         if (rsp_rc != 0) {
1058                 sdev_printk(KERN_ERR, cmd->device,
1059                             "failed to send abort() event. rc=%d\n", rsp_rc);
1060                 return FAILED;
1061         }
1062
1063         sdev_printk(KERN_INFO, cmd->device,
1064                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1065                     (((u64) lun) << 48), (u64) found_evt);
1066
1067         wait_for_completion(&evt->comp);
1068
1069         /* make sure we got a good response */
1070         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1071                 if (printk_ratelimit())
1072                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1073                                     srp_rsp.srp.rsp.opcode);
1074                 return FAILED;
1075         }
1076
1077         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1078                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1079         else
1080                 rsp_rc = srp_rsp.srp.rsp.status;
1081
1082         if (rsp_rc) {
1083                 if (printk_ratelimit())
1084                         sdev_printk(KERN_WARNING, cmd->device,
1085                                     "abort code %d for task tag 0x%llx\n",
1086                                     rsp_rc, tsk_mgmt->task_tag);
1087                 return FAILED;
1088         }
1089
1090         /* Because we dropped the spinlock above, it's possible
1091          * The event is no longer in our list.  Make sure it didn't
1092          * complete while we were aborting
1093          */
1094         spin_lock_irqsave(hostdata->host->host_lock, flags);
1095         found_evt = NULL;
1096         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1097                 if (tmp_evt->cmnd == cmd) {
1098                         found_evt = tmp_evt;
1099                         break;
1100                 }
1101         }
1102
1103         if (found_evt == NULL) {
1104                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1105                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1106                             tsk_mgmt->task_tag);
1107                 return SUCCESS;
1108         }
1109
1110         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1111                     tsk_mgmt->task_tag);
1112
1113         cmd->result = (DID_ABORT << 16);
1114         list_del(&found_evt->list);
1115         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1116                        found_evt->hostdata->dev);
1117         free_event_struct(&found_evt->hostdata->pool, found_evt);
1118         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1119         atomic_inc(&hostdata->request_limit);
1120         return SUCCESS;
1121 }
1122
1123 /**
1124  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host 
1125  * template send this over to the server and wait synchronously for the 
1126  * response
1127  */
1128 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1129 {
1130         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1131         struct srp_tsk_mgmt *tsk_mgmt;
1132         struct srp_event_struct *evt;
1133         struct srp_event_struct *tmp_evt, *pos;
1134         union viosrp_iu srp_rsp;
1135         int rsp_rc;
1136         unsigned long flags;
1137         u16 lun = lun_from_dev(cmd->device);
1138         unsigned long wait_switch = 0;
1139
1140         spin_lock_irqsave(hostdata->host->host_lock, flags);
1141         wait_switch = jiffies + (init_timeout * HZ);
1142         do {
1143                 evt = get_event_struct(&hostdata->pool);
1144                 if (evt == NULL) {
1145                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1146                         sdev_printk(KERN_ERR, cmd->device,
1147                                 "failed to allocate reset event\n");
1148                         return FAILED;
1149                 }
1150         
1151                 init_event_struct(evt,
1152                                   sync_completion,
1153                                   VIOSRP_SRP_FORMAT,
1154                                   init_timeout);
1155
1156                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1157
1158                 /* Set up a lun reset SRP command */
1159                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1160                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1161                 tsk_mgmt->lun = ((u64) lun) << 48;
1162                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1163
1164                 evt->sync_srp = &srp_rsp;
1165
1166                 init_completion(&evt->comp);
1167                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2);
1168
1169                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1170                         break;
1171
1172                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1173                 msleep(10);
1174                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1175         } while (time_before(jiffies, wait_switch));
1176
1177         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1178
1179         if (rsp_rc != 0) {
1180                 sdev_printk(KERN_ERR, cmd->device,
1181                             "failed to send reset event. rc=%d\n", rsp_rc);
1182                 return FAILED;
1183         }
1184
1185         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1186                     (((u64) lun) << 48));
1187
1188         wait_for_completion(&evt->comp);
1189
1190         /* make sure we got a good response */
1191         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1192                 if (printk_ratelimit())
1193                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1194                                     srp_rsp.srp.rsp.opcode);
1195                 return FAILED;
1196         }
1197
1198         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1199                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1200         else
1201                 rsp_rc = srp_rsp.srp.rsp.status;
1202
1203         if (rsp_rc) {
1204                 if (printk_ratelimit())
1205                         sdev_printk(KERN_WARNING, cmd->device,
1206                                     "reset code %d for task tag 0x%llx\n",
1207                                     rsp_rc, tsk_mgmt->task_tag);
1208                 return FAILED;
1209         }
1210
1211         /* We need to find all commands for this LUN that have not yet been
1212          * responded to, and fail them with DID_RESET
1213          */
1214         spin_lock_irqsave(hostdata->host->host_lock, flags);
1215         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1216                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1217                         if (tmp_evt->cmnd)
1218                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1219                         list_del(&tmp_evt->list);
1220                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1221                                        tmp_evt->hostdata->dev);
1222                         free_event_struct(&tmp_evt->hostdata->pool,
1223                                                    tmp_evt);
1224                         atomic_inc(&hostdata->request_limit);
1225                         if (tmp_evt->cmnd_done)
1226                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1227                         else if (tmp_evt->done)
1228                                 tmp_evt->done(tmp_evt);
1229                 }
1230         }
1231         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1232         return SUCCESS;
1233 }
1234
1235 /**
1236  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1237  * @cmd:        struct scsi_cmnd having problems
1238 */
1239 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1240 {
1241         unsigned long wait_switch = 0;
1242         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1243
1244         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1245
1246         ibmvscsi_reset_host(hostdata);
1247
1248         for (wait_switch = jiffies + (init_timeout * HZ);
1249              time_before(jiffies, wait_switch) &&
1250                      atomic_read(&hostdata->request_limit) < 2;) {
1251
1252                 msleep(10);
1253         }
1254
1255         if (atomic_read(&hostdata->request_limit) <= 0)
1256                 return FAILED;
1257
1258         return SUCCESS;
1259 }
1260
1261 /**
1262  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1263  * @crq:        Command/Response queue
1264  * @hostdata:   ibmvscsi_host_data of host
1265  *
1266 */
1267 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1268                          struct ibmvscsi_host_data *hostdata)
1269 {
1270         long rc;
1271         unsigned long flags;
1272         struct srp_event_struct *evt_struct =
1273             (struct srp_event_struct *)crq->IU_data_ptr;
1274         switch (crq->valid) {
1275         case 0xC0:              /* initialization */
1276                 switch (crq->format) {
1277                 case 0x01:      /* Initialization message */
1278                         dev_info(hostdata->dev, "partner initialized\n");
1279                         /* Send back a response */
1280                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1281                                                          0xC002000000000000LL, 0)) == 0) {
1282                                 /* Now login */
1283                                 send_srp_login(hostdata);
1284                         } else {
1285                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1286                         }
1287
1288                         break;
1289                 case 0x02:      /* Initialization response */
1290                         dev_info(hostdata->dev, "partner initialization complete\n");
1291
1292                         /* Now login */
1293                         send_srp_login(hostdata);
1294                         break;
1295                 default:
1296                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1297                 }
1298                 return;
1299         case 0xFF:      /* Hypervisor telling us the connection is closed */
1300                 scsi_block_requests(hostdata->host);
1301                 atomic_set(&hostdata->request_limit, 0);
1302                 if (crq->format == 0x06) {
1303                         /* We need to re-setup the interpartition connection */
1304                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1305                         purge_requests(hostdata, DID_REQUEUE);
1306                         if ((ibmvscsi_ops->reenable_crq_queue(&hostdata->queue,
1307                                                               hostdata)) ||
1308                             (ibmvscsi_ops->send_crq(hostdata,
1309                                                     0xC001000000000000LL, 0))) {
1310                                         atomic_set(&hostdata->request_limit,
1311                                                    -1);
1312                                         dev_err(hostdata->dev, "error after enable\n");
1313                         }
1314                 } else {
1315                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1316                                 crq->format);
1317
1318                         purge_requests(hostdata, DID_ERROR);
1319                         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue,
1320                                                            hostdata)) ||
1321                             (ibmvscsi_ops->send_crq(hostdata,
1322                                                     0xC001000000000000LL, 0))) {
1323                                         atomic_set(&hostdata->request_limit,
1324                                                    -1);
1325                                         dev_err(hostdata->dev, "error after reset\n");
1326                         }
1327                 }
1328                 scsi_unblock_requests(hostdata->host);
1329                 return;
1330         case 0x80:              /* real payload */
1331                 break;
1332         default:
1333                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1334                         crq->valid);
1335                 return;
1336         }
1337
1338         /* The only kind of payload CRQs we should get are responses to
1339          * things we send. Make sure this response is to something we
1340          * actually sent
1341          */
1342         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1343                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1344                        (void *)crq->IU_data_ptr);
1345                 return;
1346         }
1347
1348         if (atomic_read(&evt_struct->free)) {
1349                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1350                         (void *)crq->IU_data_ptr);
1351                 return;
1352         }
1353
1354         if (crq->format == VIOSRP_SRP_FORMAT)
1355                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1356                            &hostdata->request_limit);
1357
1358         del_timer(&evt_struct->timer);
1359
1360         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1361                 evt_struct->cmnd->result = DID_ERROR << 16;
1362         if (evt_struct->done)
1363                 evt_struct->done(evt_struct);
1364         else
1365                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1366
1367         /*
1368          * Lock the host_lock before messing with these structures, since we
1369          * are running in a task context
1370          */
1371         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1372         list_del(&evt_struct->list);
1373         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1374         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1375 }
1376
1377 /**
1378  * ibmvscsi_get_host_config: Send the command to the server to get host
1379  * configuration data.  The data is opaque to us.
1380  */
1381 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1382                                    unsigned char *buffer, int length)
1383 {
1384         struct viosrp_host_config *host_config;
1385         struct srp_event_struct *evt_struct;
1386         unsigned long flags;
1387         dma_addr_t addr;
1388         int rc;
1389
1390         evt_struct = get_event_struct(&hostdata->pool);
1391         if (!evt_struct) {
1392                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1393                 return -1;
1394         }
1395
1396         init_event_struct(evt_struct,
1397                           sync_completion,
1398                           VIOSRP_MAD_FORMAT,
1399                           init_timeout);
1400
1401         host_config = &evt_struct->iu.mad.host_config;
1402
1403         /* Set up a lun reset SRP command */
1404         memset(host_config, 0x00, sizeof(*host_config));
1405         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1406         host_config->common.length = length;
1407         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1408                                                     length,
1409                                                     DMA_BIDIRECTIONAL);
1410
1411         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1412                 if (!firmware_has_feature(FW_FEATURE_CMO))
1413                         dev_err(hostdata->dev,
1414                                 "dma_mapping error getting host config\n");
1415                 free_event_struct(&hostdata->pool, evt_struct);
1416                 return -1;
1417         }
1418
1419         init_completion(&evt_struct->comp);
1420         spin_lock_irqsave(hostdata->host->host_lock, flags);
1421         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2);
1422         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1423         if (rc == 0)
1424                 wait_for_completion(&evt_struct->comp);
1425         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1426
1427         return rc;
1428 }
1429
1430 /**
1431  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1432  * @sdev:       struct scsi_device device to configure
1433  *
1434  * Enable allow_restart for a device if it is a disk.  Adjust the
1435  * queue_depth here also as is required by the documentation for
1436  * struct scsi_host_template.
1437  */
1438 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1439 {
1440         struct Scsi_Host *shost = sdev->host;
1441         unsigned long lock_flags = 0;
1442
1443         spin_lock_irqsave(shost->host_lock, lock_flags);
1444         if (sdev->type == TYPE_DISK) {
1445                 sdev->allow_restart = 1;
1446                 blk_queue_rq_timeout(sdev->request_queue, 60 * HZ);
1447         }
1448         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1449         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1450         return 0;
1451 }
1452
1453 /**
1454  * ibmvscsi_change_queue_depth - Change the device's queue depth
1455  * @sdev:       scsi device struct
1456  * @qdepth:     depth to set
1457  *
1458  * Return value:
1459  *      actual depth set
1460  **/
1461 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1462 {
1463         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1464                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1465
1466         scsi_adjust_queue_depth(sdev, 0, qdepth);
1467         return sdev->queue_depth;
1468 }
1469
1470 /* ------------------------------------------------------------
1471  * sysfs attributes
1472  */
1473 static ssize_t show_host_srp_version(struct device *dev,
1474                                      struct device_attribute *attr, char *buf)
1475 {
1476         struct Scsi_Host *shost = class_to_shost(dev);
1477         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1478         int len;
1479
1480         len = snprintf(buf, PAGE_SIZE, "%s\n",
1481                        hostdata->madapter_info.srp_version);
1482         return len;
1483 }
1484
1485 static struct device_attribute ibmvscsi_host_srp_version = {
1486         .attr = {
1487                  .name = "srp_version",
1488                  .mode = S_IRUGO,
1489                  },
1490         .show = show_host_srp_version,
1491 };
1492
1493 static ssize_t show_host_partition_name(struct device *dev,
1494                                         struct device_attribute *attr,
1495                                         char *buf)
1496 {
1497         struct Scsi_Host *shost = class_to_shost(dev);
1498         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1499         int len;
1500
1501         len = snprintf(buf, PAGE_SIZE, "%s\n",
1502                        hostdata->madapter_info.partition_name);
1503         return len;
1504 }
1505
1506 static struct device_attribute ibmvscsi_host_partition_name = {
1507         .attr = {
1508                  .name = "partition_name",
1509                  .mode = S_IRUGO,
1510                  },
1511         .show = show_host_partition_name,
1512 };
1513
1514 static ssize_t show_host_partition_number(struct device *dev,
1515                                           struct device_attribute *attr,
1516                                           char *buf)
1517 {
1518         struct Scsi_Host *shost = class_to_shost(dev);
1519         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1520         int len;
1521
1522         len = snprintf(buf, PAGE_SIZE, "%d\n",
1523                        hostdata->madapter_info.partition_number);
1524         return len;
1525 }
1526
1527 static struct device_attribute ibmvscsi_host_partition_number = {
1528         .attr = {
1529                  .name = "partition_number",
1530                  .mode = S_IRUGO,
1531                  },
1532         .show = show_host_partition_number,
1533 };
1534
1535 static ssize_t show_host_mad_version(struct device *dev,
1536                                      struct device_attribute *attr, char *buf)
1537 {
1538         struct Scsi_Host *shost = class_to_shost(dev);
1539         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1540         int len;
1541
1542         len = snprintf(buf, PAGE_SIZE, "%d\n",
1543                        hostdata->madapter_info.mad_version);
1544         return len;
1545 }
1546
1547 static struct device_attribute ibmvscsi_host_mad_version = {
1548         .attr = {
1549                  .name = "mad_version",
1550                  .mode = S_IRUGO,
1551                  },
1552         .show = show_host_mad_version,
1553 };
1554
1555 static ssize_t show_host_os_type(struct device *dev,
1556                                  struct device_attribute *attr, char *buf)
1557 {
1558         struct Scsi_Host *shost = class_to_shost(dev);
1559         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1560         int len;
1561
1562         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1563         return len;
1564 }
1565
1566 static struct device_attribute ibmvscsi_host_os_type = {
1567         .attr = {
1568                  .name = "os_type",
1569                  .mode = S_IRUGO,
1570                  },
1571         .show = show_host_os_type,
1572 };
1573
1574 static ssize_t show_host_config(struct device *dev,
1575                                 struct device_attribute *attr, char *buf)
1576 {
1577         struct Scsi_Host *shost = class_to_shost(dev);
1578         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1579
1580         /* returns null-terminated host config data */
1581         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1582                 return strlen(buf);
1583         else
1584                 return 0;
1585 }
1586
1587 static struct device_attribute ibmvscsi_host_config = {
1588         .attr = {
1589                  .name = "config",
1590                  .mode = S_IRUGO,
1591                  },
1592         .show = show_host_config,
1593 };
1594
1595 static struct device_attribute *ibmvscsi_attrs[] = {
1596         &ibmvscsi_host_srp_version,
1597         &ibmvscsi_host_partition_name,
1598         &ibmvscsi_host_partition_number,
1599         &ibmvscsi_host_mad_version,
1600         &ibmvscsi_host_os_type,
1601         &ibmvscsi_host_config,
1602         NULL
1603 };
1604
1605 /* ------------------------------------------------------------
1606  * SCSI driver registration
1607  */
1608 static struct scsi_host_template driver_template = {
1609         .module = THIS_MODULE,
1610         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1611         .proc_name = "ibmvscsi",
1612         .queuecommand = ibmvscsi_queuecommand,
1613         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1614         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1615         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1616         .slave_configure = ibmvscsi_slave_configure,
1617         .change_queue_depth = ibmvscsi_change_queue_depth,
1618         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1619         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1620         .this_id = -1,
1621         .sg_tablesize = SG_ALL,
1622         .use_clustering = ENABLE_CLUSTERING,
1623         .shost_attrs = ibmvscsi_attrs,
1624 };
1625
1626 /**
1627  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1628  *
1629  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1630  *
1631  * Return value:
1632  *      Number of bytes of IO data the driver will need to perform well.
1633  */
1634 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1635 {
1636         /* iu_storage data allocated in initialize_event_pool */
1637         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1638
1639         /* add io space for sg data */
1640         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1641                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1642
1643         return desired_io;
1644 }
1645
1646 /**
1647  * Called by bus code for each adapter
1648  */
1649 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1650 {
1651         struct ibmvscsi_host_data *hostdata;
1652         struct Scsi_Host *host;
1653         struct device *dev = &vdev->dev;
1654         struct srp_rport_identifiers ids;
1655         struct srp_rport *rport;
1656         unsigned long wait_switch = 0;
1657         int rc;
1658
1659         vdev->dev.driver_data = NULL;
1660
1661         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1662         if (!host) {
1663                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1664                 goto scsi_host_alloc_failed;
1665         }
1666
1667         host->transportt = ibmvscsi_transport_template;
1668         hostdata = shost_priv(host);
1669         memset(hostdata, 0x00, sizeof(*hostdata));
1670         INIT_LIST_HEAD(&hostdata->sent);
1671         hostdata->host = host;
1672         hostdata->dev = dev;
1673         atomic_set(&hostdata->request_limit, -1);
1674         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1675
1676         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1677         if (rc != 0 && rc != H_RESOURCE) {
1678                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1679                 goto init_crq_failed;
1680         }
1681         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1682                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1683                 goto init_pool_failed;
1684         }
1685
1686         host->max_lun = 8;
1687         host->max_id = max_id;
1688         host->max_channel = max_channel;
1689
1690         if (scsi_add_host(hostdata->host, hostdata->dev))
1691                 goto add_host_failed;
1692
1693         /* we don't have a proper target_port_id so let's use the fake one */
1694         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1695                sizeof(ids.port_id));
1696         ids.roles = SRP_RPORT_ROLE_TARGET;
1697         rport = srp_rport_add(host, &ids);
1698         if (IS_ERR(rport))
1699                 goto add_srp_port_failed;
1700
1701         /* Try to send an initialization message.  Note that this is allowed
1702          * to fail if the other end is not acive.  In that case we don't
1703          * want to scan
1704          */
1705         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1706             || rc == H_RESOURCE) {
1707                 /*
1708                  * Wait around max init_timeout secs for the adapter to finish
1709                  * initializing. When we are done initializing, we will have a
1710                  * valid request_limit.  We don't want Linux scanning before
1711                  * we are ready.
1712                  */
1713                 for (wait_switch = jiffies + (init_timeout * HZ);
1714                      time_before(jiffies, wait_switch) &&
1715                      atomic_read(&hostdata->request_limit) < 2;) {
1716
1717                         msleep(10);
1718                 }
1719
1720                 /* if we now have a valid request_limit, initiate a scan */
1721                 if (atomic_read(&hostdata->request_limit) > 0)
1722                         scsi_scan_host(host);
1723         }
1724
1725         vdev->dev.driver_data = hostdata;
1726         return 0;
1727
1728       add_srp_port_failed:
1729         scsi_remove_host(hostdata->host);
1730       add_host_failed:
1731         release_event_pool(&hostdata->pool, hostdata);
1732       init_pool_failed:
1733         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
1734       init_crq_failed:
1735         scsi_host_put(host);
1736       scsi_host_alloc_failed:
1737         return -1;
1738 }
1739
1740 static int ibmvscsi_remove(struct vio_dev *vdev)
1741 {
1742         struct ibmvscsi_host_data *hostdata = vdev->dev.driver_data;
1743         release_event_pool(&hostdata->pool, hostdata);
1744         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
1745                                         max_events);
1746
1747         srp_remove_host(hostdata->host);
1748         scsi_remove_host(hostdata->host);
1749         scsi_host_put(hostdata->host);
1750
1751         return 0;
1752 }
1753
1754 /**
1755  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we 
1756  * support.
1757  */
1758 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1759         {"vscsi", "IBM,v-scsi"},
1760         { "", "" }
1761 };
1762 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1763
1764 static struct vio_driver ibmvscsi_driver = {
1765         .id_table = ibmvscsi_device_table,
1766         .probe = ibmvscsi_probe,
1767         .remove = ibmvscsi_remove,
1768         .get_desired_dma = ibmvscsi_get_desired_dma,
1769         .driver = {
1770                 .name = "ibmvscsi",
1771                 .owner = THIS_MODULE,
1772         }
1773 };
1774
1775 static struct srp_function_template ibmvscsi_transport_functions = {
1776 };
1777
1778 int __init ibmvscsi_module_init(void)
1779 {
1780         int ret;
1781
1782         /* Ensure we have two requests to do error recovery */
1783         driver_template.can_queue = max_requests;
1784         max_events = max_requests + 2;
1785
1786         if (firmware_has_feature(FW_FEATURE_ISERIES))
1787                 ibmvscsi_ops = &iseriesvscsi_ops;
1788         else if (firmware_has_feature(FW_FEATURE_VIO))
1789                 ibmvscsi_ops = &rpavscsi_ops;
1790         else
1791                 return -ENODEV;
1792
1793         ibmvscsi_transport_template =
1794                 srp_attach_transport(&ibmvscsi_transport_functions);
1795         if (!ibmvscsi_transport_template)
1796                 return -ENOMEM;
1797
1798         ret = vio_register_driver(&ibmvscsi_driver);
1799         if (ret)
1800                 srp_release_transport(ibmvscsi_transport_template);
1801         return ret;
1802 }
1803
1804 void __exit ibmvscsi_module_exit(void)
1805 {
1806         vio_unregister_driver(&ibmvscsi_driver);
1807         srp_release_transport(ibmvscsi_transport_template);
1808 }
1809
1810 module_init(ibmvscsi_module_init);
1811 module_exit(ibmvscsi_module_exit);