[SCSI] ibmvscsi: Send adapter info before login
[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 = 300;
91 static int login_timeout = 60;
92 static int info_timeout = 30;
93 static int abort_timeout = 60;
94 static int reset_timeout = 60;
95 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
96 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
97
98 static struct scsi_transport_template *ibmvscsi_transport_template;
99
100 #define IBMVSCSI_VERSION "1.5.8"
101
102 static struct ibmvscsi_ops *ibmvscsi_ops;
103
104 MODULE_DESCRIPTION("IBM Virtual SCSI");
105 MODULE_AUTHOR("Dave Boutcher");
106 MODULE_LICENSE("GPL");
107 MODULE_VERSION(IBMVSCSI_VERSION);
108
109 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
110 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
111 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
112 MODULE_PARM_DESC(max_channel, "Largest channel value");
113 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
114 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
115 module_param_named(max_requests, max_requests, int, S_IRUGO);
116 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
117
118 /* ------------------------------------------------------------
119  * Routines for the event pool and event structs
120  */
121 /**
122  * initialize_event_pool: - Allocates and initializes the event pool for a host
123  * @pool:       event_pool to be initialized
124  * @size:       Number of events in pool
125  * @hostdata:   ibmvscsi_host_data who owns the event pool
126  *
127  * Returns zero on success.
128 */
129 static int initialize_event_pool(struct event_pool *pool,
130                                  int size, struct ibmvscsi_host_data *hostdata)
131 {
132         int i;
133
134         pool->size = size;
135         pool->next = 0;
136         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
137         if (!pool->events)
138                 return -ENOMEM;
139
140         pool->iu_storage =
141             dma_alloc_coherent(hostdata->dev,
142                                pool->size * sizeof(*pool->iu_storage),
143                                &pool->iu_token, 0);
144         if (!pool->iu_storage) {
145                 kfree(pool->events);
146                 return -ENOMEM;
147         }
148
149         for (i = 0; i < pool->size; ++i) {
150                 struct srp_event_struct *evt = &pool->events[i];
151                 memset(&evt->crq, 0x00, sizeof(evt->crq));
152                 atomic_set(&evt->free, 1);
153                 evt->crq.valid = 0x80;
154                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
155                 evt->crq.IU_data_ptr = pool->iu_token + 
156                         sizeof(*evt->xfer_iu) * i;
157                 evt->xfer_iu = pool->iu_storage + i;
158                 evt->hostdata = hostdata;
159                 evt->ext_list = NULL;
160                 evt->ext_list_token = 0;
161         }
162
163         return 0;
164 }
165
166 /**
167  * release_event_pool: - Frees memory of an event pool of a host
168  * @pool:       event_pool to be released
169  * @hostdata:   ibmvscsi_host_data who owns the even pool
170  *
171  * Returns zero on success.
172 */
173 static void release_event_pool(struct event_pool *pool,
174                                struct ibmvscsi_host_data *hostdata)
175 {
176         int i, in_use = 0;
177         for (i = 0; i < pool->size; ++i) {
178                 if (atomic_read(&pool->events[i].free) != 1)
179                         ++in_use;
180                 if (pool->events[i].ext_list) {
181                         dma_free_coherent(hostdata->dev,
182                                   SG_ALL * sizeof(struct srp_direct_buf),
183                                   pool->events[i].ext_list,
184                                   pool->events[i].ext_list_token);
185                 }
186         }
187         if (in_use)
188                 dev_warn(hostdata->dev, "releasing event pool with %d "
189                          "events still in use?\n", in_use);
190         kfree(pool->events);
191         dma_free_coherent(hostdata->dev,
192                           pool->size * sizeof(*pool->iu_storage),
193                           pool->iu_storage, pool->iu_token);
194 }
195
196 /**
197  * valid_event_struct: - Determines if event is valid.
198  * @pool:       event_pool that contains the event
199  * @evt:        srp_event_struct to be checked for validity
200  *
201  * Returns zero if event is invalid, one otherwise.
202 */
203 static int valid_event_struct(struct event_pool *pool,
204                                 struct srp_event_struct *evt)
205 {
206         int index = evt - pool->events;
207         if (index < 0 || index >= pool->size)   /* outside of bounds */
208                 return 0;
209         if (evt != pool->events + index)        /* unaligned */
210                 return 0;
211         return 1;
212 }
213
214 /**
215  * ibmvscsi_free-event_struct: - Changes status of event to "free"
216  * @pool:       event_pool that contains the event
217  * @evt:        srp_event_struct to be modified
218  *
219 */
220 static void free_event_struct(struct event_pool *pool,
221                                        struct srp_event_struct *evt)
222 {
223         if (!valid_event_struct(pool, evt)) {
224                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
225                         "(not in pool %p)\n", evt, pool->events);
226                 return;
227         }
228         if (atomic_inc_return(&evt->free) != 1) {
229                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
230                         "which is not in use!\n", evt);
231                 return;
232         }
233 }
234
235 /**
236  * get_evt_struct: - Gets the next free event in pool
237  * @pool:       event_pool that contains the events to be searched
238  *
239  * Returns the next event in "free" state, and NULL if none are free.
240  * Note that no synchronization is done here, we assume the host_lock
241  * will syncrhonze things.
242 */
243 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
244 {
245         int i;
246         int poolsize = pool->size;
247         int offset = pool->next;
248
249         for (i = 0; i < poolsize; i++) {
250                 offset = (offset + 1) % poolsize;
251                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
252                         pool->next = offset;
253                         return &pool->events[offset];
254                 }
255         }
256
257         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
258         return NULL;
259 }
260
261 /**
262  * init_event_struct: Initialize fields in an event struct that are always 
263  *                    required.
264  * @evt:        The event
265  * @done:       Routine to call when the event is responded to
266  * @format:     SRP or MAD format
267  * @timeout:    timeout value set in the CRQ
268  */
269 static void init_event_struct(struct srp_event_struct *evt_struct,
270                               void (*done) (struct srp_event_struct *),
271                               u8 format,
272                               int timeout)
273 {
274         evt_struct->cmnd = NULL;
275         evt_struct->cmnd_done = NULL;
276         evt_struct->sync_srp = NULL;
277         evt_struct->crq.format = format;
278         evt_struct->crq.timeout = timeout;
279         evt_struct->done = done;
280 }
281
282 /* ------------------------------------------------------------
283  * Routines for receiving SCSI responses from the hosting partition
284  */
285
286 /**
287  * set_srp_direction: Set the fields in the srp related to data
288  *     direction and number of buffers based on the direction in
289  *     the scsi_cmnd and the number of buffers
290  */
291 static void set_srp_direction(struct scsi_cmnd *cmd,
292                               struct srp_cmd *srp_cmd, 
293                               int numbuf)
294 {
295         u8 fmt;
296
297         if (numbuf == 0)
298                 return;
299         
300         if (numbuf == 1)
301                 fmt = SRP_DATA_DESC_DIRECT;
302         else {
303                 fmt = SRP_DATA_DESC_INDIRECT;
304                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
305
306                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
307                         srp_cmd->data_out_desc_cnt = numbuf;
308                 else
309                         srp_cmd->data_in_desc_cnt = numbuf;
310         }
311
312         if (cmd->sc_data_direction == DMA_TO_DEVICE)
313                 srp_cmd->buf_fmt = fmt << 4;
314         else
315                 srp_cmd->buf_fmt = fmt;
316 }
317
318 static void unmap_sg_list(int num_entries,
319                 struct device *dev,
320                 struct srp_direct_buf *md)
321 {
322         int i;
323
324         for (i = 0; i < num_entries; ++i)
325                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
326 }
327
328 /**
329  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
330  * @cmd:        srp_cmd whose additional_data member will be unmapped
331  * @dev:        device for which the memory is mapped
332  *
333 */
334 static void unmap_cmd_data(struct srp_cmd *cmd,
335                            struct srp_event_struct *evt_struct,
336                            struct device *dev)
337 {
338         u8 out_fmt, in_fmt;
339
340         out_fmt = cmd->buf_fmt >> 4;
341         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
342
343         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
344                 return;
345         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
346                  in_fmt == SRP_DATA_DESC_DIRECT) {
347                 struct srp_direct_buf *data =
348                         (struct srp_direct_buf *) cmd->add_data;
349                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
350         } else {
351                 struct srp_indirect_buf *indirect =
352                         (struct srp_indirect_buf *) cmd->add_data;
353                 int num_mapped = indirect->table_desc.len /
354                         sizeof(struct srp_direct_buf);
355
356                 if (num_mapped <= MAX_INDIRECT_BUFS) {
357                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
358                         return;
359                 }
360
361                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
362         }
363 }
364
365 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
366                        struct srp_direct_buf *md)
367 {
368         int i;
369         struct scatterlist *sg;
370         u64 total_length = 0;
371
372         scsi_for_each_sg(cmd, sg, nseg, i) {
373                 struct srp_direct_buf *descr = md + i;
374                 descr->va = sg_dma_address(sg);
375                 descr->len = sg_dma_len(sg);
376                 descr->key = 0;
377                 total_length += sg_dma_len(sg);
378         }
379         return total_length;
380 }
381
382 /**
383  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
384  * @cmd:        Scsi_Cmnd with the scatterlist
385  * @srp_cmd:    srp_cmd that contains the memory descriptor
386  * @dev:        device for which to map dma memory
387  *
388  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
389  * Returns 1 on success.
390 */
391 static int map_sg_data(struct scsi_cmnd *cmd,
392                        struct srp_event_struct *evt_struct,
393                        struct srp_cmd *srp_cmd, struct device *dev)
394 {
395
396         int sg_mapped;
397         u64 total_length = 0;
398         struct srp_direct_buf *data =
399                 (struct srp_direct_buf *) srp_cmd->add_data;
400         struct srp_indirect_buf *indirect =
401                 (struct srp_indirect_buf *) data;
402
403         sg_mapped = scsi_dma_map(cmd);
404         if (!sg_mapped)
405                 return 1;
406         else if (sg_mapped < 0)
407                 return 0;
408
409         set_srp_direction(cmd, srp_cmd, sg_mapped);
410
411         /* special case; we can use a single direct descriptor */
412         if (sg_mapped == 1) {
413                 map_sg_list(cmd, sg_mapped, data);
414                 return 1;
415         }
416
417         indirect->table_desc.va = 0;
418         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
419         indirect->table_desc.key = 0;
420
421         if (sg_mapped <= MAX_INDIRECT_BUFS) {
422                 total_length = map_sg_list(cmd, sg_mapped,
423                                            &indirect->desc_list[0]);
424                 indirect->len = total_length;
425                 return 1;
426         }
427
428         /* get indirect table */
429         if (!evt_struct->ext_list) {
430                 evt_struct->ext_list = (struct srp_direct_buf *)
431                         dma_alloc_coherent(dev,
432                                            SG_ALL * sizeof(struct srp_direct_buf),
433                                            &evt_struct->ext_list_token, 0);
434                 if (!evt_struct->ext_list) {
435                         if (!firmware_has_feature(FW_FEATURE_CMO))
436                                 sdev_printk(KERN_ERR, cmd->device,
437                                             "Can't allocate memory "
438                                             "for indirect table\n");
439                         scsi_dma_unmap(cmd);
440                         return 0;
441                 }
442         }
443
444         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
445
446         indirect->len = total_length;
447         indirect->table_desc.va = evt_struct->ext_list_token;
448         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
449         memcpy(indirect->desc_list, evt_struct->ext_list,
450                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
451         return 1;
452 }
453
454 /**
455  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
456  * @cmd:        struct scsi_cmnd with the memory to be mapped
457  * @srp_cmd:    srp_cmd that contains the memory descriptor
458  * @dev:        dma device for which to map dma memory
459  *
460  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds 
461  * Returns 1 on success.
462 */
463 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
464                                 struct srp_event_struct *evt_struct,
465                                 struct srp_cmd *srp_cmd, struct device *dev)
466 {
467         switch (cmd->sc_data_direction) {
468         case DMA_FROM_DEVICE:
469         case DMA_TO_DEVICE:
470                 break;
471         case DMA_NONE:
472                 return 1;
473         case DMA_BIDIRECTIONAL:
474                 sdev_printk(KERN_ERR, cmd->device,
475                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
476                 return 0;
477         default:
478                 sdev_printk(KERN_ERR, cmd->device,
479                             "Unknown data direction 0x%02x; can't map!\n",
480                             cmd->sc_data_direction);
481                 return 0;
482         }
483
484         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
485 }
486
487 /**
488  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
489  * @hostdata:    the adapter
490  */
491 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
492 {
493         struct srp_event_struct *tmp_evt, *pos;
494         unsigned long flags;
495
496         spin_lock_irqsave(hostdata->host->host_lock, flags);
497         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
498                 list_del(&tmp_evt->list);
499                 del_timer(&tmp_evt->timer);
500                 if (tmp_evt->cmnd) {
501                         tmp_evt->cmnd->result = (error_code << 16);
502                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
503                                        tmp_evt,
504                                        tmp_evt->hostdata->dev);
505                         if (tmp_evt->cmnd_done)
506                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
507                 } else if (tmp_evt->done)
508                         tmp_evt->done(tmp_evt);
509                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
510         }
511         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
512 }
513
514 /**
515  * ibmvscsi_reset_host - Reset the connection to the server
516  * @hostdata:   struct ibmvscsi_host_data to reset
517 */
518 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
519 {
520         scsi_block_requests(hostdata->host);
521         atomic_set(&hostdata->request_limit, 0);
522
523         purge_requests(hostdata, DID_ERROR);
524         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata)) ||
525             (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0)) ||
526             (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) {
527                 atomic_set(&hostdata->request_limit, -1);
528                 dev_err(hostdata->dev, "error after reset\n");
529         }
530
531         scsi_unblock_requests(hostdata->host);
532 }
533
534 /**
535  * ibmvscsi_timeout - Internal command timeout handler
536  * @evt_struct: struct srp_event_struct that timed out
537  *
538  * Called when an internally generated command times out
539 */
540 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
541 {
542         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
543
544         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
545                 evt_struct->iu.srp.cmd.opcode);
546
547         ibmvscsi_reset_host(hostdata);
548 }
549
550
551 /* ------------------------------------------------------------
552  * Routines for sending and receiving SRPs
553  */
554 /**
555  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
556  * @evt_struct: evt_struct to be sent
557  * @hostdata:   ibmvscsi_host_data of host
558  * @timeout:    timeout in seconds - 0 means do not time command
559  *
560  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
561  * Note that this routine assumes that host_lock is held for synchronization
562 */
563 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
564                                    struct ibmvscsi_host_data *hostdata,
565                                    unsigned long timeout)
566 {
567         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
568         int request_status = 0;
569         int rc;
570
571         /* If we have exhausted our request limit, just fail this request,
572          * unless it is for a reset or abort.
573          * Note that there are rare cases involving driver generated requests 
574          * (such as task management requests) that the mid layer may think we
575          * can handle more requests (can_queue) when we actually can't
576          */
577         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
578                 request_status =
579                         atomic_dec_if_positive(&hostdata->request_limit);
580                 /* If request limit was -1 when we started, it is now even
581                  * less than that
582                  */
583                 if (request_status < -1)
584                         goto send_error;
585                 /* Otherwise, we may have run out of requests. */
586                 /* If request limit was 0 when we started the adapter is in the
587                  * process of performing a login with the server adapter, or
588                  * we may have run out of requests.
589                  */
590                 else if (request_status == -1 &&
591                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
592                         goto send_busy;
593                 /* Abort and reset calls should make it through.
594                  * Nothing except abort and reset should use the last two
595                  * slots unless we had two or less to begin with.
596                  */
597                 else if (request_status < 2 &&
598                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
599                         /* In the case that we have less than two requests
600                          * available, check the server limit as a combination
601                          * of the request limit and the number of requests
602                          * in-flight (the size of the send list).  If the
603                          * server limit is greater than 2, return busy so
604                          * that the last two are reserved for reset and abort.
605                          */
606                         int server_limit = request_status;
607                         struct srp_event_struct *tmp_evt;
608
609                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
610                                 server_limit++;
611                         }
612
613                         if (server_limit > 2)
614                                 goto send_busy;
615                 }
616         }
617
618         /* Copy the IU into the transfer area */
619         *evt_struct->xfer_iu = evt_struct->iu;
620         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
621
622         /* Add this to the sent list.  We need to do this 
623          * before we actually send 
624          * in case it comes back REALLY fast
625          */
626         list_add_tail(&evt_struct->list, &hostdata->sent);
627
628         init_timer(&evt_struct->timer);
629         if (timeout) {
630                 evt_struct->timer.data = (unsigned long) evt_struct;
631                 evt_struct->timer.expires = jiffies + (timeout * HZ);
632                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
633                 add_timer(&evt_struct->timer);
634         }
635
636         if ((rc =
637              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
638                 list_del(&evt_struct->list);
639                 del_timer(&evt_struct->timer);
640
641                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
642                  * Firmware will send a CRQ with a transport event (0xFF) to
643                  * tell this client what has happened to the transport.  This
644                  * will be handled in ibmvscsi_handle_crq()
645                  */
646                 if (rc == H_CLOSED) {
647                         dev_warn(hostdata->dev, "send warning. "
648                                  "Receive queue closed, will retry.\n");
649                         goto send_busy;
650                 }
651                 dev_err(hostdata->dev, "send error %d\n", rc);
652                 atomic_inc(&hostdata->request_limit);
653                 goto send_error;
654         }
655
656         return 0;
657
658  send_busy:
659         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
660
661         free_event_struct(&hostdata->pool, evt_struct);
662         if (request_status != -1)
663                 atomic_inc(&hostdata->request_limit);
664         return SCSI_MLQUEUE_HOST_BUSY;
665
666  send_error:
667         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
668
669         if (evt_struct->cmnd != NULL) {
670                 evt_struct->cmnd->result = DID_ERROR << 16;
671                 evt_struct->cmnd_done(evt_struct->cmnd);
672         } else if (evt_struct->done)
673                 evt_struct->done(evt_struct);
674
675         free_event_struct(&hostdata->pool, evt_struct);
676         return 0;
677 }
678
679 /**
680  * handle_cmd_rsp: -  Handle responses from commands
681  * @evt_struct: srp_event_struct to be handled
682  *
683  * Used as a callback by when sending scsi cmds.
684  * Gets called by ibmvscsi_handle_crq()
685 */
686 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
687 {
688         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
689         struct scsi_cmnd *cmnd = evt_struct->cmnd;
690
691         if (unlikely(rsp->opcode != SRP_RSP)) {
692                 if (printk_ratelimit())
693                         dev_warn(evt_struct->hostdata->dev,
694                                  "bad SRP RSP type %d\n", rsp->opcode);
695         }
696         
697         if (cmnd) {
698                 cmnd->result |= rsp->status;
699                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
700                         memcpy(cmnd->sense_buffer,
701                                rsp->data,
702                                rsp->sense_data_len);
703                 unmap_cmd_data(&evt_struct->iu.srp.cmd, 
704                                evt_struct, 
705                                evt_struct->hostdata->dev);
706
707                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
708                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
709                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
710                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
711         }
712
713         if (evt_struct->cmnd_done)
714                 evt_struct->cmnd_done(cmnd);
715 }
716
717 /**
718  * lun_from_dev: - Returns the lun of the scsi device
719  * @dev:        struct scsi_device
720  *
721 */
722 static inline u16 lun_from_dev(struct scsi_device *dev)
723 {
724         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
725 }
726
727 /**
728  * ibmvscsi_queue: - The queuecommand function of the scsi template 
729  * @cmd:        struct scsi_cmnd to be executed
730  * @done:       Callback function to be called when cmd is completed
731 */
732 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
733                                  void (*done) (struct scsi_cmnd *))
734 {
735         struct srp_cmd *srp_cmd;
736         struct srp_event_struct *evt_struct;
737         struct srp_indirect_buf *indirect;
738         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
739         u16 lun = lun_from_dev(cmnd->device);
740         u8 out_fmt, in_fmt;
741
742         cmnd->result = (DID_OK << 16);
743         evt_struct = get_event_struct(&hostdata->pool);
744         if (!evt_struct)
745                 return SCSI_MLQUEUE_HOST_BUSY;
746
747         /* Set up the actual SRP IU */
748         srp_cmd = &evt_struct->iu.srp.cmd;
749         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
750         srp_cmd->opcode = SRP_CMD;
751         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
752         srp_cmd->lun = ((u64) lun) << 48;
753
754         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
755                 if (!firmware_has_feature(FW_FEATURE_CMO))
756                         sdev_printk(KERN_ERR, cmnd->device,
757                                     "couldn't convert cmd to srp_cmd\n");
758                 free_event_struct(&hostdata->pool, evt_struct);
759                 return SCSI_MLQUEUE_HOST_BUSY;
760         }
761
762         init_event_struct(evt_struct,
763                           handle_cmd_rsp,
764                           VIOSRP_SRP_FORMAT,
765                           cmnd->request->timeout/HZ);
766
767         evt_struct->cmnd = cmnd;
768         evt_struct->cmnd_done = done;
769
770         /* Fix up dma address of the buffer itself */
771         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
772         out_fmt = srp_cmd->buf_fmt >> 4;
773         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
774         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
775              out_fmt == SRP_DATA_DESC_INDIRECT) &&
776             indirect->table_desc.va == 0) {
777                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
778                         offsetof(struct srp_cmd, add_data) +
779                         offsetof(struct srp_indirect_buf, desc_list);
780         }
781
782         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
783 }
784
785 /* ------------------------------------------------------------
786  * Routines for driver initialization
787  */
788
789 /**
790  * login_rsp: - Handle response to SRP login request
791  * @evt_struct: srp_event_struct with the response
792  *
793  * Used as a "done" callback by when sending srp_login. Gets called
794  * by ibmvscsi_handle_crq()
795 */
796 static void login_rsp(struct srp_event_struct *evt_struct)
797 {
798         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
799         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
800         case SRP_LOGIN_RSP:     /* it worked! */
801                 break;
802         case SRP_LOGIN_REJ:     /* refused! */
803                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
804                          evt_struct->xfer_iu->srp.login_rej.reason);
805                 /* Login failed.  */
806                 atomic_set(&hostdata->request_limit, -1);
807                 return;
808         default:
809                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
810                         evt_struct->xfer_iu->srp.login_rsp.opcode);
811                 /* Login failed.  */
812                 atomic_set(&hostdata->request_limit, -1);
813                 return;
814         }
815
816         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
817
818         /* Now we know what the real request-limit is.
819          * This value is set rather than added to request_limit because
820          * request_limit could have been set to -1 by this client.
821          */
822         atomic_set(&hostdata->request_limit,
823                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
824
825         /* If we had any pending I/Os, kick them */
826         scsi_unblock_requests(hostdata->host);
827 }
828
829 /**
830  * send_srp_login: - Sends the srp login
831  * @hostdata:   ibmvscsi_host_data of host
832  *
833  * Returns zero if successful.
834 */
835 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
836 {
837         int rc;
838         unsigned long flags;
839         struct srp_login_req *login;
840         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
841
842         BUG_ON(!evt_struct);
843         init_event_struct(evt_struct, login_rsp,
844                           VIOSRP_SRP_FORMAT, login_timeout);
845
846         login = &evt_struct->iu.srp.login_req;
847         memset(login, 0, sizeof(*login));
848         login->opcode = SRP_LOGIN_REQ;
849         login->req_it_iu_len = sizeof(union srp_iu);
850         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
851
852         spin_lock_irqsave(hostdata->host->host_lock, flags);
853         /* Start out with a request limit of 0, since this is negotiated in
854          * the login request we are just sending and login requests always
855          * get sent by the driver regardless of request_limit.
856          */
857         atomic_set(&hostdata->request_limit, 0);
858
859         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
860         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
861         dev_info(hostdata->dev, "sent SRP login\n");
862         return rc;
863 };
864
865 /**
866  * adapter_info_rsp: - Handle response to MAD adapter info request
867  * @evt_struct: srp_event_struct with the response
868  *
869  * Used as a "done" callback by when sending adapter_info. Gets called
870  * by ibmvscsi_handle_crq()
871 */
872 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
873 {
874         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
875         dma_unmap_single(hostdata->dev,
876                          evt_struct->iu.mad.adapter_info.buffer,
877                          evt_struct->iu.mad.adapter_info.common.length,
878                          DMA_BIDIRECTIONAL);
879
880         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
881                 dev_err(hostdata->dev, "error %d getting adapter info\n",
882                         evt_struct->xfer_iu->mad.adapter_info.common.status);
883         } else {
884                 dev_info(hostdata->dev, "host srp version: %s, "
885                          "host partition %s (%d), OS %d, max io %u\n",
886                          hostdata->madapter_info.srp_version,
887                          hostdata->madapter_info.partition_name,
888                          hostdata->madapter_info.partition_number,
889                          hostdata->madapter_info.os_type,
890                          hostdata->madapter_info.port_max_txu[0]);
891                 
892                 if (hostdata->madapter_info.port_max_txu[0]) 
893                         hostdata->host->max_sectors = 
894                                 hostdata->madapter_info.port_max_txu[0] >> 9;
895                 
896                 if (hostdata->madapter_info.os_type == 3 &&
897                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
898                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
899                                 hostdata->madapter_info.srp_version);
900                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
901                                 MAX_INDIRECT_BUFS);
902                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
903                 }
904         }
905
906         send_srp_login(hostdata);
907 }
908
909 /**
910  * send_mad_adapter_info: - Sends the mad adapter info request
911  *      and stores the result so it can be retrieved with
912  *      sysfs.  We COULD consider causing a failure if the
913  *      returned SRP version doesn't match ours.
914  * @hostdata:   ibmvscsi_host_data of host
915  * 
916  * Returns zero if successful.
917 */
918 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
919 {
920         struct viosrp_adapter_info *req;
921         struct srp_event_struct *evt_struct;
922         unsigned long flags;
923         dma_addr_t addr;
924
925         evt_struct = get_event_struct(&hostdata->pool);
926         BUG_ON(!evt_struct);
927
928         init_event_struct(evt_struct,
929                           adapter_info_rsp,
930                           VIOSRP_MAD_FORMAT,
931                           info_timeout);
932         
933         req = &evt_struct->iu.mad.adapter_info;
934         memset(req, 0x00, sizeof(*req));
935         
936         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
937         req->common.length = sizeof(hostdata->madapter_info);
938         req->buffer = addr = dma_map_single(hostdata->dev,
939                                             &hostdata->madapter_info,
940                                             sizeof(hostdata->madapter_info),
941                                             DMA_BIDIRECTIONAL);
942
943         if (dma_mapping_error(hostdata->dev, req->buffer)) {
944                 if (!firmware_has_feature(FW_FEATURE_CMO))
945                         dev_err(hostdata->dev,
946                                 "Unable to map request_buffer for "
947                                 "adapter_info!\n");
948                 free_event_struct(&hostdata->pool, evt_struct);
949                 return;
950         }
951         
952         spin_lock_irqsave(hostdata->host->host_lock, flags);
953         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2)) {
954                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
955                 dma_unmap_single(hostdata->dev,
956                                  addr,
957                                  sizeof(hostdata->madapter_info),
958                                  DMA_BIDIRECTIONAL);
959         }
960         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
961 };
962
963 /**
964  * init_adapter: Start virtual adapter initialization sequence
965  *
966  */
967 static void init_adapter(struct ibmvscsi_host_data *hostdata)
968 {
969         send_mad_adapter_info(hostdata);
970 }
971
972 /**
973  * sync_completion: Signal that a synchronous command has completed
974  * Note that after returning from this call, the evt_struct is freed.
975  * the caller waiting on this completion shouldn't touch the evt_struct
976  * again.
977  */
978 static void sync_completion(struct srp_event_struct *evt_struct)
979 {
980         /* copy the response back */
981         if (evt_struct->sync_srp)
982                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
983         
984         complete(&evt_struct->comp);
985 }
986
987 /**
988  * ibmvscsi_abort: Abort a command...from scsi host template
989  * send this over to the server and wait synchronously for the response
990  */
991 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
992 {
993         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
994         struct srp_tsk_mgmt *tsk_mgmt;
995         struct srp_event_struct *evt;
996         struct srp_event_struct *tmp_evt, *found_evt;
997         union viosrp_iu srp_rsp;
998         int rsp_rc;
999         unsigned long flags;
1000         u16 lun = lun_from_dev(cmd->device);
1001         unsigned long wait_switch = 0;
1002
1003         /* First, find this command in our sent list so we can figure
1004          * out the correct tag
1005          */
1006         spin_lock_irqsave(hostdata->host->host_lock, flags);
1007         wait_switch = jiffies + (init_timeout * HZ);
1008         do {
1009                 found_evt = NULL;
1010                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1011                         if (tmp_evt->cmnd == cmd) {
1012                                 found_evt = tmp_evt;
1013                                 break;
1014                         }
1015                 }
1016
1017                 if (!found_evt) {
1018                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1019                         return SUCCESS;
1020                 }
1021
1022                 evt = get_event_struct(&hostdata->pool);
1023                 if (evt == NULL) {
1024                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1025                         sdev_printk(KERN_ERR, cmd->device,
1026                                 "failed to allocate abort event\n");
1027                         return FAILED;
1028                 }
1029         
1030                 init_event_struct(evt,
1031                                   sync_completion,
1032                                   VIOSRP_SRP_FORMAT,
1033                                   abort_timeout);
1034
1035                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1036         
1037                 /* Set up an abort SRP command */
1038                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1039                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1040                 tsk_mgmt->lun = ((u64) lun) << 48;
1041                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1042                 tsk_mgmt->task_tag = (u64) found_evt;
1043
1044                 evt->sync_srp = &srp_rsp;
1045
1046                 init_completion(&evt->comp);
1047                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1048
1049                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1050                         break;
1051
1052                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1053                 msleep(10);
1054                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1055         } while (time_before(jiffies, wait_switch));
1056
1057         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1058
1059         if (rsp_rc != 0) {
1060                 sdev_printk(KERN_ERR, cmd->device,
1061                             "failed to send abort() event. rc=%d\n", rsp_rc);
1062                 return FAILED;
1063         }
1064
1065         sdev_printk(KERN_INFO, cmd->device,
1066                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1067                     (((u64) lun) << 48), (u64) found_evt);
1068
1069         wait_for_completion(&evt->comp);
1070
1071         /* make sure we got a good response */
1072         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1073                 if (printk_ratelimit())
1074                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1075                                     srp_rsp.srp.rsp.opcode);
1076                 return FAILED;
1077         }
1078
1079         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1080                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1081         else
1082                 rsp_rc = srp_rsp.srp.rsp.status;
1083
1084         if (rsp_rc) {
1085                 if (printk_ratelimit())
1086                         sdev_printk(KERN_WARNING, cmd->device,
1087                                     "abort code %d for task tag 0x%llx\n",
1088                                     rsp_rc, tsk_mgmt->task_tag);
1089                 return FAILED;
1090         }
1091
1092         /* Because we dropped the spinlock above, it's possible
1093          * The event is no longer in our list.  Make sure it didn't
1094          * complete while we were aborting
1095          */
1096         spin_lock_irqsave(hostdata->host->host_lock, flags);
1097         found_evt = NULL;
1098         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1099                 if (tmp_evt->cmnd == cmd) {
1100                         found_evt = tmp_evt;
1101                         break;
1102                 }
1103         }
1104
1105         if (found_evt == NULL) {
1106                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1107                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1108                             tsk_mgmt->task_tag);
1109                 return SUCCESS;
1110         }
1111
1112         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1113                     tsk_mgmt->task_tag);
1114
1115         cmd->result = (DID_ABORT << 16);
1116         list_del(&found_evt->list);
1117         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1118                        found_evt->hostdata->dev);
1119         free_event_struct(&found_evt->hostdata->pool, found_evt);
1120         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1121         atomic_inc(&hostdata->request_limit);
1122         return SUCCESS;
1123 }
1124
1125 /**
1126  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host 
1127  * template send this over to the server and wait synchronously for the 
1128  * response
1129  */
1130 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1131 {
1132         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1133         struct srp_tsk_mgmt *tsk_mgmt;
1134         struct srp_event_struct *evt;
1135         struct srp_event_struct *tmp_evt, *pos;
1136         union viosrp_iu srp_rsp;
1137         int rsp_rc;
1138         unsigned long flags;
1139         u16 lun = lun_from_dev(cmd->device);
1140         unsigned long wait_switch = 0;
1141
1142         spin_lock_irqsave(hostdata->host->host_lock, flags);
1143         wait_switch = jiffies + (init_timeout * HZ);
1144         do {
1145                 evt = get_event_struct(&hostdata->pool);
1146                 if (evt == NULL) {
1147                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1148                         sdev_printk(KERN_ERR, cmd->device,
1149                                 "failed to allocate reset event\n");
1150                         return FAILED;
1151                 }
1152         
1153                 init_event_struct(evt,
1154                                   sync_completion,
1155                                   VIOSRP_SRP_FORMAT,
1156                                   reset_timeout);
1157
1158                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1159
1160                 /* Set up a lun reset SRP command */
1161                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1162                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1163                 tsk_mgmt->lun = ((u64) lun) << 48;
1164                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1165
1166                 evt->sync_srp = &srp_rsp;
1167
1168                 init_completion(&evt->comp);
1169                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1170
1171                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1172                         break;
1173
1174                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1175                 msleep(10);
1176                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1177         } while (time_before(jiffies, wait_switch));
1178
1179         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1180
1181         if (rsp_rc != 0) {
1182                 sdev_printk(KERN_ERR, cmd->device,
1183                             "failed to send reset event. rc=%d\n", rsp_rc);
1184                 return FAILED;
1185         }
1186
1187         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1188                     (((u64) lun) << 48));
1189
1190         wait_for_completion(&evt->comp);
1191
1192         /* make sure we got a good response */
1193         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1194                 if (printk_ratelimit())
1195                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1196                                     srp_rsp.srp.rsp.opcode);
1197                 return FAILED;
1198         }
1199
1200         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1201                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1202         else
1203                 rsp_rc = srp_rsp.srp.rsp.status;
1204
1205         if (rsp_rc) {
1206                 if (printk_ratelimit())
1207                         sdev_printk(KERN_WARNING, cmd->device,
1208                                     "reset code %d for task tag 0x%llx\n",
1209                                     rsp_rc, tsk_mgmt->task_tag);
1210                 return FAILED;
1211         }
1212
1213         /* We need to find all commands for this LUN that have not yet been
1214          * responded to, and fail them with DID_RESET
1215          */
1216         spin_lock_irqsave(hostdata->host->host_lock, flags);
1217         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1218                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1219                         if (tmp_evt->cmnd)
1220                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1221                         list_del(&tmp_evt->list);
1222                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1223                                        tmp_evt->hostdata->dev);
1224                         free_event_struct(&tmp_evt->hostdata->pool,
1225                                                    tmp_evt);
1226                         atomic_inc(&hostdata->request_limit);
1227                         if (tmp_evt->cmnd_done)
1228                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1229                         else if (tmp_evt->done)
1230                                 tmp_evt->done(tmp_evt);
1231                 }
1232         }
1233         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1234         return SUCCESS;
1235 }
1236
1237 /**
1238  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1239  * @cmd:        struct scsi_cmnd having problems
1240 */
1241 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1242 {
1243         unsigned long wait_switch = 0;
1244         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1245
1246         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1247
1248         ibmvscsi_reset_host(hostdata);
1249
1250         for (wait_switch = jiffies + (init_timeout * HZ);
1251              time_before(jiffies, wait_switch) &&
1252                      atomic_read(&hostdata->request_limit) < 2;) {
1253
1254                 msleep(10);
1255         }
1256
1257         if (atomic_read(&hostdata->request_limit) <= 0)
1258                 return FAILED;
1259
1260         return SUCCESS;
1261 }
1262
1263 /**
1264  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1265  * @crq:        Command/Response queue
1266  * @hostdata:   ibmvscsi_host_data of host
1267  *
1268 */
1269 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1270                          struct ibmvscsi_host_data *hostdata)
1271 {
1272         long rc;
1273         unsigned long flags;
1274         struct srp_event_struct *evt_struct =
1275             (struct srp_event_struct *)crq->IU_data_ptr;
1276         switch (crq->valid) {
1277         case 0xC0:              /* initialization */
1278                 switch (crq->format) {
1279                 case 0x01:      /* Initialization message */
1280                         dev_info(hostdata->dev, "partner initialized\n");
1281                         /* Send back a response */
1282                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1283                                                          0xC002000000000000LL, 0)) == 0) {
1284                                 /* Now login */
1285                                 init_adapter(hostdata);
1286                         } else {
1287                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1288                         }
1289
1290                         break;
1291                 case 0x02:      /* Initialization response */
1292                         dev_info(hostdata->dev, "partner initialization complete\n");
1293
1294                         /* Now login */
1295                         init_adapter(hostdata);
1296                         break;
1297                 default:
1298                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1299                 }
1300                 return;
1301         case 0xFF:      /* Hypervisor telling us the connection is closed */
1302                 scsi_block_requests(hostdata->host);
1303                 atomic_set(&hostdata->request_limit, 0);
1304                 if (crq->format == 0x06) {
1305                         /* We need to re-setup the interpartition connection */
1306                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1307                         purge_requests(hostdata, DID_REQUEUE);
1308                         if ((ibmvscsi_ops->reenable_crq_queue(&hostdata->queue,
1309                                                               hostdata)) ||
1310                             (ibmvscsi_ops->send_crq(hostdata,
1311                                                     0xC001000000000000LL, 0))) {
1312                                         atomic_set(&hostdata->request_limit,
1313                                                    -1);
1314                                         dev_err(hostdata->dev, "error after enable\n");
1315                         }
1316                 } else {
1317                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1318                                 crq->format);
1319
1320                         purge_requests(hostdata, DID_ERROR);
1321                         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue,
1322                                                            hostdata)) ||
1323                             (ibmvscsi_ops->send_crq(hostdata,
1324                                                     0xC001000000000000LL, 0))) {
1325                                         atomic_set(&hostdata->request_limit,
1326                                                    -1);
1327                                         dev_err(hostdata->dev, "error after reset\n");
1328                         }
1329                 }
1330                 scsi_unblock_requests(hostdata->host);
1331                 return;
1332         case 0x80:              /* real payload */
1333                 break;
1334         default:
1335                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1336                         crq->valid);
1337                 return;
1338         }
1339
1340         /* The only kind of payload CRQs we should get are responses to
1341          * things we send. Make sure this response is to something we
1342          * actually sent
1343          */
1344         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1345                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1346                        (void *)crq->IU_data_ptr);
1347                 return;
1348         }
1349
1350         if (atomic_read(&evt_struct->free)) {
1351                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1352                         (void *)crq->IU_data_ptr);
1353                 return;
1354         }
1355
1356         if (crq->format == VIOSRP_SRP_FORMAT)
1357                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1358                            &hostdata->request_limit);
1359
1360         del_timer(&evt_struct->timer);
1361
1362         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1363                 evt_struct->cmnd->result = DID_ERROR << 16;
1364         if (evt_struct->done)
1365                 evt_struct->done(evt_struct);
1366         else
1367                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1368
1369         /*
1370          * Lock the host_lock before messing with these structures, since we
1371          * are running in a task context
1372          */
1373         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1374         list_del(&evt_struct->list);
1375         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1376         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1377 }
1378
1379 /**
1380  * ibmvscsi_get_host_config: Send the command to the server to get host
1381  * configuration data.  The data is opaque to us.
1382  */
1383 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1384                                    unsigned char *buffer, int length)
1385 {
1386         struct viosrp_host_config *host_config;
1387         struct srp_event_struct *evt_struct;
1388         unsigned long flags;
1389         dma_addr_t addr;
1390         int rc;
1391
1392         evt_struct = get_event_struct(&hostdata->pool);
1393         if (!evt_struct) {
1394                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1395                 return -1;
1396         }
1397
1398         init_event_struct(evt_struct,
1399                           sync_completion,
1400                           VIOSRP_MAD_FORMAT,
1401                           info_timeout);
1402
1403         host_config = &evt_struct->iu.mad.host_config;
1404
1405         /* Set up a lun reset SRP command */
1406         memset(host_config, 0x00, sizeof(*host_config));
1407         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1408         host_config->common.length = length;
1409         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1410                                                     length,
1411                                                     DMA_BIDIRECTIONAL);
1412
1413         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1414                 if (!firmware_has_feature(FW_FEATURE_CMO))
1415                         dev_err(hostdata->dev,
1416                                 "dma_mapping error getting host config\n");
1417                 free_event_struct(&hostdata->pool, evt_struct);
1418                 return -1;
1419         }
1420
1421         init_completion(&evt_struct->comp);
1422         spin_lock_irqsave(hostdata->host->host_lock, flags);
1423         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1424         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1425         if (rc == 0)
1426                 wait_for_completion(&evt_struct->comp);
1427         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1428
1429         return rc;
1430 }
1431
1432 /**
1433  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1434  * @sdev:       struct scsi_device device to configure
1435  *
1436  * Enable allow_restart for a device if it is a disk.  Adjust the
1437  * queue_depth here also as is required by the documentation for
1438  * struct scsi_host_template.
1439  */
1440 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1441 {
1442         struct Scsi_Host *shost = sdev->host;
1443         unsigned long lock_flags = 0;
1444
1445         spin_lock_irqsave(shost->host_lock, lock_flags);
1446         if (sdev->type == TYPE_DISK) {
1447                 sdev->allow_restart = 1;
1448                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1449         }
1450         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1451         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1452         return 0;
1453 }
1454
1455 /**
1456  * ibmvscsi_change_queue_depth - Change the device's queue depth
1457  * @sdev:       scsi device struct
1458  * @qdepth:     depth to set
1459  *
1460  * Return value:
1461  *      actual depth set
1462  **/
1463 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1464 {
1465         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1466                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1467
1468         scsi_adjust_queue_depth(sdev, 0, qdepth);
1469         return sdev->queue_depth;
1470 }
1471
1472 /* ------------------------------------------------------------
1473  * sysfs attributes
1474  */
1475 static ssize_t show_host_srp_version(struct device *dev,
1476                                      struct device_attribute *attr, char *buf)
1477 {
1478         struct Scsi_Host *shost = class_to_shost(dev);
1479         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1480         int len;
1481
1482         len = snprintf(buf, PAGE_SIZE, "%s\n",
1483                        hostdata->madapter_info.srp_version);
1484         return len;
1485 }
1486
1487 static struct device_attribute ibmvscsi_host_srp_version = {
1488         .attr = {
1489                  .name = "srp_version",
1490                  .mode = S_IRUGO,
1491                  },
1492         .show = show_host_srp_version,
1493 };
1494
1495 static ssize_t show_host_partition_name(struct device *dev,
1496                                         struct device_attribute *attr,
1497                                         char *buf)
1498 {
1499         struct Scsi_Host *shost = class_to_shost(dev);
1500         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1501         int len;
1502
1503         len = snprintf(buf, PAGE_SIZE, "%s\n",
1504                        hostdata->madapter_info.partition_name);
1505         return len;
1506 }
1507
1508 static struct device_attribute ibmvscsi_host_partition_name = {
1509         .attr = {
1510                  .name = "partition_name",
1511                  .mode = S_IRUGO,
1512                  },
1513         .show = show_host_partition_name,
1514 };
1515
1516 static ssize_t show_host_partition_number(struct device *dev,
1517                                           struct device_attribute *attr,
1518                                           char *buf)
1519 {
1520         struct Scsi_Host *shost = class_to_shost(dev);
1521         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1522         int len;
1523
1524         len = snprintf(buf, PAGE_SIZE, "%d\n",
1525                        hostdata->madapter_info.partition_number);
1526         return len;
1527 }
1528
1529 static struct device_attribute ibmvscsi_host_partition_number = {
1530         .attr = {
1531                  .name = "partition_number",
1532                  .mode = S_IRUGO,
1533                  },
1534         .show = show_host_partition_number,
1535 };
1536
1537 static ssize_t show_host_mad_version(struct device *dev,
1538                                      struct device_attribute *attr, char *buf)
1539 {
1540         struct Scsi_Host *shost = class_to_shost(dev);
1541         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1542         int len;
1543
1544         len = snprintf(buf, PAGE_SIZE, "%d\n",
1545                        hostdata->madapter_info.mad_version);
1546         return len;
1547 }
1548
1549 static struct device_attribute ibmvscsi_host_mad_version = {
1550         .attr = {
1551                  .name = "mad_version",
1552                  .mode = S_IRUGO,
1553                  },
1554         .show = show_host_mad_version,
1555 };
1556
1557 static ssize_t show_host_os_type(struct device *dev,
1558                                  struct device_attribute *attr, char *buf)
1559 {
1560         struct Scsi_Host *shost = class_to_shost(dev);
1561         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1562         int len;
1563
1564         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1565         return len;
1566 }
1567
1568 static struct device_attribute ibmvscsi_host_os_type = {
1569         .attr = {
1570                  .name = "os_type",
1571                  .mode = S_IRUGO,
1572                  },
1573         .show = show_host_os_type,
1574 };
1575
1576 static ssize_t show_host_config(struct device *dev,
1577                                 struct device_attribute *attr, char *buf)
1578 {
1579         struct Scsi_Host *shost = class_to_shost(dev);
1580         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1581
1582         /* returns null-terminated host config data */
1583         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1584                 return strlen(buf);
1585         else
1586                 return 0;
1587 }
1588
1589 static struct device_attribute ibmvscsi_host_config = {
1590         .attr = {
1591                  .name = "config",
1592                  .mode = S_IRUGO,
1593                  },
1594         .show = show_host_config,
1595 };
1596
1597 static struct device_attribute *ibmvscsi_attrs[] = {
1598         &ibmvscsi_host_srp_version,
1599         &ibmvscsi_host_partition_name,
1600         &ibmvscsi_host_partition_number,
1601         &ibmvscsi_host_mad_version,
1602         &ibmvscsi_host_os_type,
1603         &ibmvscsi_host_config,
1604         NULL
1605 };
1606
1607 /* ------------------------------------------------------------
1608  * SCSI driver registration
1609  */
1610 static struct scsi_host_template driver_template = {
1611         .module = THIS_MODULE,
1612         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1613         .proc_name = "ibmvscsi",
1614         .queuecommand = ibmvscsi_queuecommand,
1615         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1616         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1617         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1618         .slave_configure = ibmvscsi_slave_configure,
1619         .change_queue_depth = ibmvscsi_change_queue_depth,
1620         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1621         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1622         .this_id = -1,
1623         .sg_tablesize = SG_ALL,
1624         .use_clustering = ENABLE_CLUSTERING,
1625         .shost_attrs = ibmvscsi_attrs,
1626 };
1627
1628 /**
1629  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1630  *
1631  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1632  *
1633  * Return value:
1634  *      Number of bytes of IO data the driver will need to perform well.
1635  */
1636 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1637 {
1638         /* iu_storage data allocated in initialize_event_pool */
1639         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1640
1641         /* add io space for sg data */
1642         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1643                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1644
1645         return desired_io;
1646 }
1647
1648 /**
1649  * Called by bus code for each adapter
1650  */
1651 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1652 {
1653         struct ibmvscsi_host_data *hostdata;
1654         struct Scsi_Host *host;
1655         struct device *dev = &vdev->dev;
1656         struct srp_rport_identifiers ids;
1657         struct srp_rport *rport;
1658         unsigned long wait_switch = 0;
1659         int rc;
1660
1661         vdev->dev.driver_data = NULL;
1662
1663         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1664         if (!host) {
1665                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1666                 goto scsi_host_alloc_failed;
1667         }
1668
1669         host->transportt = ibmvscsi_transport_template;
1670         hostdata = shost_priv(host);
1671         memset(hostdata, 0x00, sizeof(*hostdata));
1672         INIT_LIST_HEAD(&hostdata->sent);
1673         hostdata->host = host;
1674         hostdata->dev = dev;
1675         atomic_set(&hostdata->request_limit, -1);
1676         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1677
1678         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1679         if (rc != 0 && rc != H_RESOURCE) {
1680                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1681                 goto init_crq_failed;
1682         }
1683         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1684                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1685                 goto init_pool_failed;
1686         }
1687
1688         host->max_lun = 8;
1689         host->max_id = max_id;
1690         host->max_channel = max_channel;
1691         host->max_cmd_len = 16;
1692
1693         if (scsi_add_host(hostdata->host, hostdata->dev))
1694                 goto add_host_failed;
1695
1696         /* we don't have a proper target_port_id so let's use the fake one */
1697         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1698                sizeof(ids.port_id));
1699         ids.roles = SRP_RPORT_ROLE_TARGET;
1700         rport = srp_rport_add(host, &ids);
1701         if (IS_ERR(rport))
1702                 goto add_srp_port_failed;
1703
1704         /* Try to send an initialization message.  Note that this is allowed
1705          * to fail if the other end is not acive.  In that case we don't
1706          * want to scan
1707          */
1708         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1709             || rc == H_RESOURCE) {
1710                 /*
1711                  * Wait around max init_timeout secs for the adapter to finish
1712                  * initializing. When we are done initializing, we will have a
1713                  * valid request_limit.  We don't want Linux scanning before
1714                  * we are ready.
1715                  */
1716                 for (wait_switch = jiffies + (init_timeout * HZ);
1717                      time_before(jiffies, wait_switch) &&
1718                      atomic_read(&hostdata->request_limit) < 2;) {
1719
1720                         msleep(10);
1721                 }
1722
1723                 /* if we now have a valid request_limit, initiate a scan */
1724                 if (atomic_read(&hostdata->request_limit) > 0)
1725                         scsi_scan_host(host);
1726         }
1727
1728         vdev->dev.driver_data = hostdata;
1729         return 0;
1730
1731       add_srp_port_failed:
1732         scsi_remove_host(hostdata->host);
1733       add_host_failed:
1734         release_event_pool(&hostdata->pool, hostdata);
1735       init_pool_failed:
1736         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
1737       init_crq_failed:
1738         scsi_host_put(host);
1739       scsi_host_alloc_failed:
1740         return -1;
1741 }
1742
1743 static int ibmvscsi_remove(struct vio_dev *vdev)
1744 {
1745         struct ibmvscsi_host_data *hostdata = vdev->dev.driver_data;
1746         release_event_pool(&hostdata->pool, hostdata);
1747         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
1748                                         max_events);
1749
1750         srp_remove_host(hostdata->host);
1751         scsi_remove_host(hostdata->host);
1752         scsi_host_put(hostdata->host);
1753
1754         return 0;
1755 }
1756
1757 /**
1758  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we 
1759  * support.
1760  */
1761 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1762         {"vscsi", "IBM,v-scsi"},
1763         { "", "" }
1764 };
1765 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1766
1767 static struct vio_driver ibmvscsi_driver = {
1768         .id_table = ibmvscsi_device_table,
1769         .probe = ibmvscsi_probe,
1770         .remove = ibmvscsi_remove,
1771         .get_desired_dma = ibmvscsi_get_desired_dma,
1772         .driver = {
1773                 .name = "ibmvscsi",
1774                 .owner = THIS_MODULE,
1775         }
1776 };
1777
1778 static struct srp_function_template ibmvscsi_transport_functions = {
1779 };
1780
1781 int __init ibmvscsi_module_init(void)
1782 {
1783         int ret;
1784
1785         /* Ensure we have two requests to do error recovery */
1786         driver_template.can_queue = max_requests;
1787         max_events = max_requests + 2;
1788
1789         if (firmware_has_feature(FW_FEATURE_ISERIES))
1790                 ibmvscsi_ops = &iseriesvscsi_ops;
1791         else if (firmware_has_feature(FW_FEATURE_VIO))
1792                 ibmvscsi_ops = &rpavscsi_ops;
1793         else
1794                 return -ENODEV;
1795
1796         ibmvscsi_transport_template =
1797                 srp_attach_transport(&ibmvscsi_transport_functions);
1798         if (!ibmvscsi_transport_template)
1799                 return -ENOMEM;
1800
1801         ret = vio_register_driver(&ibmvscsi_driver);
1802         if (ret)
1803                 srp_release_transport(ibmvscsi_transport_template);
1804         return ret;
1805 }
1806
1807 void __exit ibmvscsi_module_exit(void)
1808 {
1809         vio_unregister_driver(&ibmvscsi_driver);
1810         srp_release_transport(ibmvscsi_transport_template);
1811 }
1812
1813 module_init(ibmvscsi_module_init);
1814 module_exit(ibmvscsi_module_exit);