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