1 /*
2  * IBM eServer i/pSeries Virtual SCSI Target Driver
3  * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
4  *			   Santiago Leon (santil@us.ibm.com) IBM Corp.
5  *			   Linda Xie (lxie@us.ibm.com) IBM Corp.
6  *
7  * Copyright (C) 2005-2006 FUJITA Tomonori <tomof@acm.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
22  * USA
23  */
24 #include <linux/interrupt.h>
25 #include <linux/module.h>
26 #include <linux/slab.h>
27 #include <scsi/scsi.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_transport_srp.h>
30 #include <scsi/scsi_tgt.h>
31 #include <scsi/libsrp.h>
32 #include <asm/hvcall.h>
33 #include <asm/iommu.h>
34 #include <asm/prom.h>
35 #include <asm/vio.h>
36 
37 #include "ibmvscsi.h"
38 
39 #define	INITIAL_SRP_LIMIT	16
40 #define	DEFAULT_MAX_SECTORS	256
41 
42 #define	TGT_NAME	"ibmvstgt"
43 
44 /*
45  * Hypervisor calls.
46  */
47 #define h_copy_rdma(l, sa, sb, da, db) \
48 			plpar_hcall_norets(H_COPY_RDMA, l, sa, sb, da, db)
49 #define h_send_crq(ua, l, h) \
50 			plpar_hcall_norets(H_SEND_CRQ, ua, l, h)
51 #define h_reg_crq(ua, tok, sz)\
52 			plpar_hcall_norets(H_REG_CRQ, ua, tok, sz);
53 #define h_free_crq(ua) \
54 			plpar_hcall_norets(H_FREE_CRQ, ua);
55 
56 /* tmp - will replace with SCSI logging stuff */
57 #define eprintk(fmt, args...)					\
58 do {								\
59 	printk("%s(%d) " fmt, __func__, __LINE__, ##args);	\
60 } while (0)
61 /* #define dprintk eprintk */
62 #define dprintk(fmt, args...)
63 
64 struct vio_port {
65 	struct vio_dev *dma_dev;
66 
67 	struct crq_queue crq_queue;
68 	struct work_struct crq_work;
69 
70 	unsigned long liobn;
71 	unsigned long riobn;
72 	struct srp_target *target;
73 
74 	struct srp_rport *rport;
75 };
76 
77 static struct workqueue_struct *vtgtd;
78 static struct scsi_transport_template *ibmvstgt_transport_template;
79 
80 /*
81  * These are fixed for the system and come from the Open Firmware device tree.
82  * We just store them here to save getting them every time.
83  */
84 static char system_id[64] = "";
85 static char partition_name[97] = "UNKNOWN";
86 static unsigned int partition_number = -1;
87 
target_to_port(struct srp_target * target)88 static struct vio_port *target_to_port(struct srp_target *target)
89 {
90 	return (struct vio_port *) target->ldata;
91 }
92 
vio_iu(struct iu_entry * iue)93 static inline union viosrp_iu *vio_iu(struct iu_entry *iue)
94 {
95 	return (union viosrp_iu *) (iue->sbuf->buf);
96 }
97 
send_iu(struct iu_entry * iue,uint64_t length,uint8_t format)98 static int send_iu(struct iu_entry *iue, uint64_t length, uint8_t format)
99 {
100 	struct srp_target *target = iue->target;
101 	struct vio_port *vport = target_to_port(target);
102 	long rc, rc1;
103 	union {
104 		struct viosrp_crq cooked;
105 		uint64_t raw[2];
106 	} crq;
107 
108 	/* First copy the SRP */
109 	rc = h_copy_rdma(length, vport->liobn, iue->sbuf->dma,
110 			 vport->riobn, iue->remote_token);
111 
112 	if (rc)
113 		eprintk("Error %ld transferring data\n", rc);
114 
115 	crq.cooked.valid = 0x80;
116 	crq.cooked.format = format;
117 	crq.cooked.reserved = 0x00;
118 	crq.cooked.timeout = 0x00;
119 	crq.cooked.IU_length = length;
120 	crq.cooked.IU_data_ptr = vio_iu(iue)->srp.rsp.tag;
121 
122 	if (rc == 0)
123 		crq.cooked.status = 0x99;	/* Just needs to be non-zero */
124 	else
125 		crq.cooked.status = 0x00;
126 
127 	rc1 = h_send_crq(vport->dma_dev->unit_address, crq.raw[0], crq.raw[1]);
128 
129 	if (rc1) {
130 		eprintk("%ld sending response\n", rc1);
131 		return rc1;
132 	}
133 
134 	return rc;
135 }
136 
137 #define SRP_RSP_SENSE_DATA_LEN	18
138 
send_rsp(struct iu_entry * iue,struct scsi_cmnd * sc,unsigned char status,unsigned char asc)139 static int send_rsp(struct iu_entry *iue, struct scsi_cmnd *sc,
140 		    unsigned char status, unsigned char asc)
141 {
142 	union viosrp_iu *iu = vio_iu(iue);
143 	uint64_t tag = iu->srp.rsp.tag;
144 
145 	/* If the linked bit is on and status is good */
146 	if (test_bit(V_LINKED, &iue->flags) && (status == NO_SENSE))
147 		status = 0x10;
148 
149 	memset(iu, 0, sizeof(struct srp_rsp));
150 	iu->srp.rsp.opcode = SRP_RSP;
151 	iu->srp.rsp.req_lim_delta = 1;
152 	iu->srp.rsp.tag = tag;
153 
154 	if (test_bit(V_DIOVER, &iue->flags))
155 		iu->srp.rsp.flags |= SRP_RSP_FLAG_DIOVER;
156 
157 	iu->srp.rsp.data_in_res_cnt = 0;
158 	iu->srp.rsp.data_out_res_cnt = 0;
159 
160 	iu->srp.rsp.flags &= ~SRP_RSP_FLAG_RSPVALID;
161 
162 	iu->srp.rsp.resp_data_len = 0;
163 	iu->srp.rsp.status = status;
164 	if (status) {
165 		uint8_t *sense = iu->srp.rsp.data;
166 
167 		if (sc) {
168 			iu->srp.rsp.flags |= SRP_RSP_FLAG_SNSVALID;
169 			iu->srp.rsp.sense_data_len = SCSI_SENSE_BUFFERSIZE;
170 			memcpy(sense, sc->sense_buffer, SCSI_SENSE_BUFFERSIZE);
171 		} else {
172 			iu->srp.rsp.status = SAM_STAT_CHECK_CONDITION;
173 			iu->srp.rsp.flags |= SRP_RSP_FLAG_SNSVALID;
174 			iu->srp.rsp.sense_data_len = SRP_RSP_SENSE_DATA_LEN;
175 
176 			/* Valid bit and 'current errors' */
177 			sense[0] = (0x1 << 7 | 0x70);
178 			/* Sense key */
179 			sense[2] = status;
180 			/* Additional sense length */
181 			sense[7] = 0xa;	/* 10 bytes */
182 			/* Additional sense code */
183 			sense[12] = asc;
184 		}
185 	}
186 
187 	send_iu(iue, sizeof(iu->srp.rsp) + SRP_RSP_SENSE_DATA_LEN,
188 		VIOSRP_SRP_FORMAT);
189 
190 	return 0;
191 }
192 
handle_cmd_queue(struct srp_target * target)193 static void handle_cmd_queue(struct srp_target *target)
194 {
195 	struct Scsi_Host *shost = target->shost;
196 	struct srp_rport *rport = target_to_port(target)->rport;
197 	struct iu_entry *iue;
198 	struct srp_cmd *cmd;
199 	unsigned long flags;
200 	int err;
201 
202 retry:
203 	spin_lock_irqsave(&target->lock, flags);
204 
205 	list_for_each_entry(iue, &target->cmd_queue, ilist) {
206 		if (!test_and_set_bit(V_FLYING, &iue->flags)) {
207 			spin_unlock_irqrestore(&target->lock, flags);
208 			cmd = iue->sbuf->buf;
209 			err = srp_cmd_queue(shost, cmd, iue,
210 					    (unsigned long)rport, 0);
211 			if (err) {
212 				eprintk("cannot queue cmd %p %d\n", cmd, err);
213 				srp_iu_put(iue);
214 			}
215 			goto retry;
216 		}
217 	}
218 
219 	spin_unlock_irqrestore(&target->lock, flags);
220 }
221 
ibmvstgt_rdma(struct scsi_cmnd * sc,struct scatterlist * sg,int nsg,struct srp_direct_buf * md,int nmd,enum dma_data_direction dir,unsigned int rest)222 static int ibmvstgt_rdma(struct scsi_cmnd *sc, struct scatterlist *sg, int nsg,
223 			 struct srp_direct_buf *md, int nmd,
224 			 enum dma_data_direction dir, unsigned int rest)
225 {
226 	struct iu_entry *iue = (struct iu_entry *) sc->SCp.ptr;
227 	struct srp_target *target = iue->target;
228 	struct vio_port *vport = target_to_port(target);
229 	dma_addr_t token;
230 	long err;
231 	unsigned int done = 0;
232 	int i, sidx, soff;
233 
234 	sidx = soff = 0;
235 	token = sg_dma_address(sg + sidx);
236 
237 	for (i = 0; i < nmd && rest; i++) {
238 		unsigned int mdone, mlen;
239 
240 		mlen = min(rest, md[i].len);
241 		for (mdone = 0; mlen;) {
242 			int slen = min(sg_dma_len(sg + sidx) - soff, mlen);
243 
244 			if (dir == DMA_TO_DEVICE)
245 				err = h_copy_rdma(slen,
246 						  vport->riobn,
247 						  md[i].va + mdone,
248 						  vport->liobn,
249 						  token + soff);
250 			else
251 				err = h_copy_rdma(slen,
252 						  vport->liobn,
253 						  token + soff,
254 						  vport->riobn,
255 						  md[i].va + mdone);
256 
257 			if (err != H_SUCCESS) {
258 				eprintk("rdma error %d %d %ld\n", dir, slen, err);
259 				return -EIO;
260 			}
261 
262 			mlen -= slen;
263 			mdone += slen;
264 			soff += slen;
265 			done += slen;
266 
267 			if (soff == sg_dma_len(sg + sidx)) {
268 				sidx++;
269 				soff = 0;
270 				token = sg_dma_address(sg + sidx);
271 
272 				if (sidx > nsg) {
273 					eprintk("out of sg %p %d %d\n",
274 						iue, sidx, nsg);
275 					return -EIO;
276 				}
277 			}
278 		};
279 
280 		rest -= mlen;
281 	}
282 	return 0;
283 }
284 
ibmvstgt_cmd_done(struct scsi_cmnd * sc,void (* done)(struct scsi_cmnd *))285 static int ibmvstgt_cmd_done(struct scsi_cmnd *sc,
286 			     void (*done)(struct scsi_cmnd *))
287 {
288 	unsigned long flags;
289 	struct iu_entry *iue = (struct iu_entry *) sc->SCp.ptr;
290 	struct srp_target *target = iue->target;
291 	int err = 0;
292 
293 	dprintk("%p %p %x %u\n", iue, target, vio_iu(iue)->srp.cmd.cdb[0],
294 		scsi_sg_count(sc));
295 
296 	if (scsi_sg_count(sc))
297 		err = srp_transfer_data(sc, &vio_iu(iue)->srp.cmd, ibmvstgt_rdma, 1, 1);
298 
299 	spin_lock_irqsave(&target->lock, flags);
300 	list_del(&iue->ilist);
301 	spin_unlock_irqrestore(&target->lock, flags);
302 
303 	if (err|| sc->result != SAM_STAT_GOOD) {
304 		eprintk("operation failed %p %d %x\n",
305 			iue, sc->result, vio_iu(iue)->srp.cmd.cdb[0]);
306 		send_rsp(iue, sc, HARDWARE_ERROR, 0x00);
307 	} else
308 		send_rsp(iue, sc, NO_SENSE, 0x00);
309 
310 	done(sc);
311 	srp_iu_put(iue);
312 	return 0;
313 }
314 
send_adapter_info(struct iu_entry * iue,dma_addr_t remote_buffer,uint16_t length)315 int send_adapter_info(struct iu_entry *iue,
316 		      dma_addr_t remote_buffer, uint16_t length)
317 {
318 	struct srp_target *target = iue->target;
319 	struct vio_port *vport = target_to_port(target);
320 	struct Scsi_Host *shost = target->shost;
321 	dma_addr_t data_token;
322 	struct mad_adapter_info_data *info;
323 	int err;
324 
325 	info = dma_alloc_coherent(target->dev, sizeof(*info), &data_token,
326 				  GFP_KERNEL);
327 	if (!info) {
328 		eprintk("bad dma_alloc_coherent %p\n", target);
329 		return 1;
330 	}
331 
332 	/* Get remote info */
333 	err = h_copy_rdma(sizeof(*info), vport->riobn, remote_buffer,
334 			  vport->liobn, data_token);
335 	if (err == H_SUCCESS) {
336 		dprintk("Client connect: %s (%d)\n",
337 			info->partition_name, info->partition_number);
338 	}
339 
340 	memset(info, 0, sizeof(*info));
341 
342 	strcpy(info->srp_version, "16.a");
343 	strncpy(info->partition_name, partition_name,
344 		sizeof(info->partition_name));
345 	info->partition_number = partition_number;
346 	info->mad_version = 1;
347 	info->os_type = 2;
348 	info->port_max_txu[0] = shost->hostt->max_sectors << 9;
349 
350 	/* Send our info to remote */
351 	err = h_copy_rdma(sizeof(*info), vport->liobn, data_token,
352 			  vport->riobn, remote_buffer);
353 
354 	dma_free_coherent(target->dev, sizeof(*info), info, data_token);
355 
356 	if (err != H_SUCCESS) {
357 		eprintk("Error sending adapter info %d\n", err);
358 		return 1;
359 	}
360 
361 	return 0;
362 }
363 
process_login(struct iu_entry * iue)364 static void process_login(struct iu_entry *iue)
365 {
366 	union viosrp_iu *iu = vio_iu(iue);
367 	struct srp_login_rsp *rsp = &iu->srp.login_rsp;
368 	uint64_t tag = iu->srp.rsp.tag;
369 	struct Scsi_Host *shost = iue->target->shost;
370 	struct srp_target *target = host_to_srp_target(shost);
371 	struct vio_port *vport = target_to_port(target);
372 	struct srp_rport_identifiers ids;
373 
374 	memset(&ids, 0, sizeof(ids));
375 	sprintf(ids.port_id, "%x", vport->dma_dev->unit_address);
376 	ids.roles = SRP_RPORT_ROLE_INITIATOR;
377 	if (!vport->rport)
378 		vport->rport = srp_rport_add(shost, &ids);
379 
380 	/* TODO handle case that requested size is wrong and
381 	 * buffer format is wrong
382 	 */
383 	memset(iu, 0, sizeof(struct srp_login_rsp));
384 	rsp->opcode = SRP_LOGIN_RSP;
385 	rsp->req_lim_delta = INITIAL_SRP_LIMIT;
386 	rsp->tag = tag;
387 	rsp->max_it_iu_len = sizeof(union srp_iu);
388 	rsp->max_ti_iu_len = sizeof(union srp_iu);
389 	/* direct and indirect */
390 	rsp->buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
391 
392 	send_iu(iue, sizeof(*rsp), VIOSRP_SRP_FORMAT);
393 }
394 
queue_cmd(struct iu_entry * iue)395 static inline void queue_cmd(struct iu_entry *iue)
396 {
397 	struct srp_target *target = iue->target;
398 	unsigned long flags;
399 
400 	spin_lock_irqsave(&target->lock, flags);
401 	list_add_tail(&iue->ilist, &target->cmd_queue);
402 	spin_unlock_irqrestore(&target->lock, flags);
403 }
404 
process_tsk_mgmt(struct iu_entry * iue)405 static int process_tsk_mgmt(struct iu_entry *iue)
406 {
407 	union viosrp_iu *iu = vio_iu(iue);
408 	int fn;
409 
410 	dprintk("%p %u\n", iue, iu->srp.tsk_mgmt.tsk_mgmt_func);
411 
412 	switch (iu->srp.tsk_mgmt.tsk_mgmt_func) {
413 	case SRP_TSK_ABORT_TASK:
414 		fn = ABORT_TASK;
415 		break;
416 	case SRP_TSK_ABORT_TASK_SET:
417 		fn = ABORT_TASK_SET;
418 		break;
419 	case SRP_TSK_CLEAR_TASK_SET:
420 		fn = CLEAR_TASK_SET;
421 		break;
422 	case SRP_TSK_LUN_RESET:
423 		fn = LOGICAL_UNIT_RESET;
424 		break;
425 	case SRP_TSK_CLEAR_ACA:
426 		fn = CLEAR_ACA;
427 		break;
428 	default:
429 		fn = 0;
430 	}
431 	if (fn)
432 		scsi_tgt_tsk_mgmt_request(iue->target->shost,
433 					  (unsigned long)iue->target->shost,
434 					  fn,
435 					  iu->srp.tsk_mgmt.task_tag,
436 					  (struct scsi_lun *) &iu->srp.tsk_mgmt.lun,
437 					  iue);
438 	else
439 		send_rsp(iue, NULL, ILLEGAL_REQUEST, 0x20);
440 
441 	return !fn;
442 }
443 
process_mad_iu(struct iu_entry * iue)444 static int process_mad_iu(struct iu_entry *iue)
445 {
446 	union viosrp_iu *iu = vio_iu(iue);
447 	struct viosrp_adapter_info *info;
448 	struct viosrp_host_config *conf;
449 
450 	switch (iu->mad.empty_iu.common.type) {
451 	case VIOSRP_EMPTY_IU_TYPE:
452 		eprintk("%s\n", "Unsupported EMPTY MAD IU");
453 		break;
454 	case VIOSRP_ERROR_LOG_TYPE:
455 		eprintk("%s\n", "Unsupported ERROR LOG MAD IU");
456 		iu->mad.error_log.common.status = 1;
457 		send_iu(iue, sizeof(iu->mad.error_log),	VIOSRP_MAD_FORMAT);
458 		break;
459 	case VIOSRP_ADAPTER_INFO_TYPE:
460 		info = &iu->mad.adapter_info;
461 		info->common.status = send_adapter_info(iue, info->buffer,
462 							info->common.length);
463 		send_iu(iue, sizeof(*info), VIOSRP_MAD_FORMAT);
464 		break;
465 	case VIOSRP_HOST_CONFIG_TYPE:
466 		conf = &iu->mad.host_config;
467 		conf->common.status = 1;
468 		send_iu(iue, sizeof(*conf), VIOSRP_MAD_FORMAT);
469 		break;
470 	default:
471 		eprintk("Unknown type %u\n", iu->srp.rsp.opcode);
472 	}
473 
474 	return 1;
475 }
476 
process_srp_iu(struct iu_entry * iue)477 static int process_srp_iu(struct iu_entry *iue)
478 {
479 	union viosrp_iu *iu = vio_iu(iue);
480 	int done = 1;
481 	u8 opcode = iu->srp.rsp.opcode;
482 
483 	switch (opcode) {
484 	case SRP_LOGIN_REQ:
485 		process_login(iue);
486 		break;
487 	case SRP_TSK_MGMT:
488 		done = process_tsk_mgmt(iue);
489 		break;
490 	case SRP_CMD:
491 		queue_cmd(iue);
492 		done = 0;
493 		break;
494 	case SRP_LOGIN_RSP:
495 	case SRP_I_LOGOUT:
496 	case SRP_T_LOGOUT:
497 	case SRP_RSP:
498 	case SRP_CRED_REQ:
499 	case SRP_CRED_RSP:
500 	case SRP_AER_REQ:
501 	case SRP_AER_RSP:
502 		eprintk("Unsupported type %u\n", opcode);
503 		break;
504 	default:
505 		eprintk("Unknown type %u\n", opcode);
506 	}
507 
508 	return done;
509 }
510 
process_iu(struct viosrp_crq * crq,struct srp_target * target)511 static void process_iu(struct viosrp_crq *crq, struct srp_target *target)
512 {
513 	struct vio_port *vport = target_to_port(target);
514 	struct iu_entry *iue;
515 	long err;
516 	int done = 1;
517 
518 	iue = srp_iu_get(target);
519 	if (!iue) {
520 		eprintk("Error getting IU from pool, %p\n", target);
521 		return;
522 	}
523 
524 	iue->remote_token = crq->IU_data_ptr;
525 
526 	err = h_copy_rdma(crq->IU_length, vport->riobn,
527 			  iue->remote_token, vport->liobn, iue->sbuf->dma);
528 
529 	if (err != H_SUCCESS) {
530 		eprintk("%ld transferring data error %p\n", err, iue);
531 		goto out;
532 	}
533 
534 	if (crq->format == VIOSRP_MAD_FORMAT)
535 		done = process_mad_iu(iue);
536 	else
537 		done = process_srp_iu(iue);
538 out:
539 	if (done)
540 		srp_iu_put(iue);
541 }
542 
ibmvstgt_interrupt(int dummy,void * data)543 static irqreturn_t ibmvstgt_interrupt(int dummy, void *data)
544 {
545 	struct srp_target *target = data;
546 	struct vio_port *vport = target_to_port(target);
547 
548 	vio_disable_interrupts(vport->dma_dev);
549 	queue_work(vtgtd, &vport->crq_work);
550 
551 	return IRQ_HANDLED;
552 }
553 
crq_queue_create(struct crq_queue * queue,struct srp_target * target)554 static int crq_queue_create(struct crq_queue *queue, struct srp_target *target)
555 {
556 	int err;
557 	struct vio_port *vport = target_to_port(target);
558 
559 	queue->msgs = (struct viosrp_crq *) get_zeroed_page(GFP_KERNEL);
560 	if (!queue->msgs)
561 		goto malloc_failed;
562 	queue->size = PAGE_SIZE / sizeof(*queue->msgs);
563 
564 	queue->msg_token = dma_map_single(target->dev, queue->msgs,
565 					  queue->size * sizeof(*queue->msgs),
566 					  DMA_BIDIRECTIONAL);
567 
568 	if (dma_mapping_error(target->dev, queue->msg_token))
569 		goto map_failed;
570 
571 	err = h_reg_crq(vport->dma_dev->unit_address, queue->msg_token,
572 			PAGE_SIZE);
573 
574 	/* If the adapter was left active for some reason (like kexec)
575 	 * try freeing and re-registering
576 	 */
577 	if (err == H_RESOURCE) {
578 	    do {
579 		err = h_free_crq(vport->dma_dev->unit_address);
580 	    } while (err == H_BUSY || H_IS_LONG_BUSY(err));
581 
582 	    err = h_reg_crq(vport->dma_dev->unit_address, queue->msg_token,
583 			    PAGE_SIZE);
584 	}
585 
586 	if (err != H_SUCCESS && err != 2) {
587 		eprintk("Error 0x%x opening virtual adapter\n", err);
588 		goto reg_crq_failed;
589 	}
590 
591 	err = request_irq(vport->dma_dev->irq, &ibmvstgt_interrupt,
592 			  IRQF_DISABLED, "ibmvstgt", target);
593 	if (err)
594 		goto req_irq_failed;
595 
596 	vio_enable_interrupts(vport->dma_dev);
597 
598 	h_send_crq(vport->dma_dev->unit_address, 0xC001000000000000, 0);
599 
600 	queue->cur = 0;
601 	spin_lock_init(&queue->lock);
602 
603 	return 0;
604 
605 req_irq_failed:
606 	do {
607 		err = h_free_crq(vport->dma_dev->unit_address);
608 	} while (err == H_BUSY || H_IS_LONG_BUSY(err));
609 
610 reg_crq_failed:
611 	dma_unmap_single(target->dev, queue->msg_token,
612 			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
613 map_failed:
614 	free_page((unsigned long) queue->msgs);
615 
616 malloc_failed:
617 	return -ENOMEM;
618 }
619 
crq_queue_destroy(struct srp_target * target)620 static void crq_queue_destroy(struct srp_target *target)
621 {
622 	struct vio_port *vport = target_to_port(target);
623 	struct crq_queue *queue = &vport->crq_queue;
624 	int err;
625 
626 	free_irq(vport->dma_dev->irq, target);
627 	do {
628 		err = h_free_crq(vport->dma_dev->unit_address);
629 	} while (err == H_BUSY || H_IS_LONG_BUSY(err));
630 
631 	dma_unmap_single(target->dev, queue->msg_token,
632 			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
633 
634 	free_page((unsigned long) queue->msgs);
635 }
636 
process_crq(struct viosrp_crq * crq,struct srp_target * target)637 static void process_crq(struct viosrp_crq *crq,	struct srp_target *target)
638 {
639 	struct vio_port *vport = target_to_port(target);
640 	dprintk("%x %x\n", crq->valid, crq->format);
641 
642 	switch (crq->valid) {
643 	case 0xC0:
644 		/* initialization */
645 		switch (crq->format) {
646 		case 0x01:
647 			h_send_crq(vport->dma_dev->unit_address,
648 				   0xC002000000000000, 0);
649 			break;
650 		case 0x02:
651 			break;
652 		default:
653 			eprintk("Unknown format %u\n", crq->format);
654 		}
655 		break;
656 	case 0xFF:
657 		/* transport event */
658 		break;
659 	case 0x80:
660 		/* real payload */
661 		switch (crq->format) {
662 		case VIOSRP_SRP_FORMAT:
663 		case VIOSRP_MAD_FORMAT:
664 			process_iu(crq, target);
665 			break;
666 		case VIOSRP_OS400_FORMAT:
667 		case VIOSRP_AIX_FORMAT:
668 		case VIOSRP_LINUX_FORMAT:
669 		case VIOSRP_INLINE_FORMAT:
670 			eprintk("Unsupported format %u\n", crq->format);
671 			break;
672 		default:
673 			eprintk("Unknown format %u\n", crq->format);
674 		}
675 		break;
676 	default:
677 		eprintk("unknown message type 0x%02x!?\n", crq->valid);
678 	}
679 }
680 
next_crq(struct crq_queue * queue)681 static inline struct viosrp_crq *next_crq(struct crq_queue *queue)
682 {
683 	struct viosrp_crq *crq;
684 	unsigned long flags;
685 
686 	spin_lock_irqsave(&queue->lock, flags);
687 	crq = &queue->msgs[queue->cur];
688 	if (crq->valid & 0x80) {
689 		if (++queue->cur == queue->size)
690 			queue->cur = 0;
691 	} else
692 		crq = NULL;
693 	spin_unlock_irqrestore(&queue->lock, flags);
694 
695 	return crq;
696 }
697 
handle_crq(struct work_struct * work)698 static void handle_crq(struct work_struct *work)
699 {
700 	struct vio_port *vport = container_of(work, struct vio_port, crq_work);
701 	struct srp_target *target = vport->target;
702 	struct viosrp_crq *crq;
703 	int done = 0;
704 
705 	while (!done) {
706 		while ((crq = next_crq(&vport->crq_queue)) != NULL) {
707 			process_crq(crq, target);
708 			crq->valid = 0x00;
709 		}
710 
711 		vio_enable_interrupts(vport->dma_dev);
712 
713 		crq = next_crq(&vport->crq_queue);
714 		if (crq) {
715 			vio_disable_interrupts(vport->dma_dev);
716 			process_crq(crq, target);
717 			crq->valid = 0x00;
718 		} else
719 			done = 1;
720 	}
721 
722 	handle_cmd_queue(target);
723 }
724 
725 
ibmvstgt_eh_abort_handler(struct scsi_cmnd * sc)726 static int ibmvstgt_eh_abort_handler(struct scsi_cmnd *sc)
727 {
728 	unsigned long flags;
729 	struct iu_entry *iue = (struct iu_entry *) sc->SCp.ptr;
730 	struct srp_target *target = iue->target;
731 
732 	dprintk("%p %p %x\n", iue, target, vio_iu(iue)->srp.cmd.cdb[0]);
733 
734 	spin_lock_irqsave(&target->lock, flags);
735 	list_del(&iue->ilist);
736 	spin_unlock_irqrestore(&target->lock, flags);
737 
738 	srp_iu_put(iue);
739 
740 	return 0;
741 }
742 
ibmvstgt_tsk_mgmt_response(struct Scsi_Host * shost,u64 itn_id,u64 mid,int result)743 static int ibmvstgt_tsk_mgmt_response(struct Scsi_Host *shost,
744 				      u64 itn_id, u64 mid, int result)
745 {
746 	struct iu_entry *iue = (struct iu_entry *) ((void *) mid);
747 	union viosrp_iu *iu = vio_iu(iue);
748 	unsigned char status, asc;
749 
750 	eprintk("%p %d\n", iue, result);
751 	status = NO_SENSE;
752 	asc = 0;
753 
754 	switch (iu->srp.tsk_mgmt.tsk_mgmt_func) {
755 	case SRP_TSK_ABORT_TASK:
756 		asc = 0x14;
757 		if (result)
758 			status = ABORTED_COMMAND;
759 		break;
760 	default:
761 		break;
762 	}
763 
764 	send_rsp(iue, NULL, status, asc);
765 	srp_iu_put(iue);
766 
767 	return 0;
768 }
769 
ibmvstgt_it_nexus_response(struct Scsi_Host * shost,u64 itn_id,int result)770 static int ibmvstgt_it_nexus_response(struct Scsi_Host *shost, u64 itn_id,
771 				      int result)
772 {
773 	struct srp_target *target = host_to_srp_target(shost);
774 	struct vio_port *vport = target_to_port(target);
775 
776 	if (result) {
777 		eprintk("%p %d\n", shost, result);
778 		srp_rport_del(vport->rport);
779 		vport->rport = NULL;
780 	}
781 	return 0;
782 }
783 
system_id_show(struct device * dev,struct device_attribute * attr,char * buf)784 static ssize_t system_id_show(struct device *dev,
785 			      struct device_attribute *attr, char *buf)
786 {
787 	return snprintf(buf, PAGE_SIZE, "%s\n", system_id);
788 }
789 
partition_number_show(struct device * dev,struct device_attribute * attr,char * buf)790 static ssize_t partition_number_show(struct device *dev,
791 				     struct device_attribute *attr, char *buf)
792 {
793 	return snprintf(buf, PAGE_SIZE, "%x\n", partition_number);
794 }
795 
unit_address_show(struct device * dev,struct device_attribute * attr,char * buf)796 static ssize_t unit_address_show(struct device *dev,
797 				  struct device_attribute *attr, char *buf)
798 {
799 	struct Scsi_Host *shost = class_to_shost(dev);
800 	struct srp_target *target = host_to_srp_target(shost);
801 	struct vio_port *vport = target_to_port(target);
802 	return snprintf(buf, PAGE_SIZE, "%x\n", vport->dma_dev->unit_address);
803 }
804 
805 static DEVICE_ATTR(system_id, S_IRUGO, system_id_show, NULL);
806 static DEVICE_ATTR(partition_number, S_IRUGO, partition_number_show, NULL);
807 static DEVICE_ATTR(unit_address, S_IRUGO, unit_address_show, NULL);
808 
809 static struct device_attribute *ibmvstgt_attrs[] = {
810 	&dev_attr_system_id,
811 	&dev_attr_partition_number,
812 	&dev_attr_unit_address,
813 	NULL,
814 };
815 
816 static struct scsi_host_template ibmvstgt_sht = {
817 	.name			= TGT_NAME,
818 	.module			= THIS_MODULE,
819 	.can_queue		= INITIAL_SRP_LIMIT,
820 	.sg_tablesize		= SG_ALL,
821 	.use_clustering		= DISABLE_CLUSTERING,
822 	.max_sectors		= DEFAULT_MAX_SECTORS,
823 	.transfer_response	= ibmvstgt_cmd_done,
824 	.eh_abort_handler	= ibmvstgt_eh_abort_handler,
825 	.shost_attrs		= ibmvstgt_attrs,
826 	.proc_name		= TGT_NAME,
827 	.supported_mode		= MODE_TARGET,
828 };
829 
ibmvstgt_probe(struct vio_dev * dev,const struct vio_device_id * id)830 static int ibmvstgt_probe(struct vio_dev *dev, const struct vio_device_id *id)
831 {
832 	struct Scsi_Host *shost;
833 	struct srp_target *target;
834 	struct vio_port *vport;
835 	unsigned int *dma, dma_size;
836 	int err = -ENOMEM;
837 
838 	vport = kzalloc(sizeof(struct vio_port), GFP_KERNEL);
839 	if (!vport)
840 		return err;
841 	shost = scsi_host_alloc(&ibmvstgt_sht, sizeof(struct srp_target));
842 	if (!shost)
843 		goto free_vport;
844 	shost->transportt = ibmvstgt_transport_template;
845 
846 	target = host_to_srp_target(shost);
847 	target->shost = shost;
848 	vport->dma_dev = dev;
849 	target->ldata = vport;
850 	vport->target = target;
851 	err = srp_target_alloc(target, &dev->dev, INITIAL_SRP_LIMIT,
852 			       SRP_MAX_IU_LEN);
853 	if (err)
854 		goto put_host;
855 
856 	dma = (unsigned int *) vio_get_attribute(dev, "ibm,my-dma-window",
857 						 &dma_size);
858 	if (!dma || dma_size != 40) {
859 		eprintk("Couldn't get window property %d\n", dma_size);
860 		err = -EIO;
861 		goto free_srp_target;
862 	}
863 	vport->liobn = dma[0];
864 	vport->riobn = dma[5];
865 
866 	INIT_WORK(&vport->crq_work, handle_crq);
867 
868 	err = scsi_add_host(shost, target->dev);
869 	if (err)
870 		goto free_srp_target;
871 
872 	err = scsi_tgt_alloc_queue(shost);
873 	if (err)
874 		goto remove_host;
875 
876 	err = crq_queue_create(&vport->crq_queue, target);
877 	if (err)
878 		goto free_queue;
879 
880 	return 0;
881 free_queue:
882 	scsi_tgt_free_queue(shost);
883 remove_host:
884 	scsi_remove_host(shost);
885 free_srp_target:
886 	srp_target_free(target);
887 put_host:
888 	scsi_host_put(shost);
889 free_vport:
890 	kfree(vport);
891 	return err;
892 }
893 
ibmvstgt_remove(struct vio_dev * dev)894 static int ibmvstgt_remove(struct vio_dev *dev)
895 {
896 	struct srp_target *target = dev_get_drvdata(&dev->dev);
897 	struct Scsi_Host *shost = target->shost;
898 	struct vio_port *vport = target->ldata;
899 
900 	crq_queue_destroy(target);
901 	srp_remove_host(shost);
902 	scsi_remove_host(shost);
903 	scsi_tgt_free_queue(shost);
904 	srp_target_free(target);
905 	kfree(vport);
906 	scsi_host_put(shost);
907 	return 0;
908 }
909 
910 static struct vio_device_id ibmvstgt_device_table[] __devinitdata = {
911 	{"v-scsi-host", "IBM,v-scsi-host"},
912 	{"",""}
913 };
914 
915 MODULE_DEVICE_TABLE(vio, ibmvstgt_device_table);
916 
917 static struct vio_driver ibmvstgt_driver = {
918 	.id_table = ibmvstgt_device_table,
919 	.probe = ibmvstgt_probe,
920 	.remove = ibmvstgt_remove,
921 	.driver = {
922 		.name = "ibmvscsis",
923 		.owner = THIS_MODULE,
924 	}
925 };
926 
get_system_info(void)927 static int get_system_info(void)
928 {
929 	struct device_node *rootdn;
930 	const char *id, *model, *name;
931 	const unsigned int *num;
932 
933 	rootdn = of_find_node_by_path("/");
934 	if (!rootdn)
935 		return -ENOENT;
936 
937 	model = of_get_property(rootdn, "model", NULL);
938 	id = of_get_property(rootdn, "system-id", NULL);
939 	if (model && id)
940 		snprintf(system_id, sizeof(system_id), "%s-%s", model, id);
941 
942 	name = of_get_property(rootdn, "ibm,partition-name", NULL);
943 	if (name)
944 		strncpy(partition_name, name, sizeof(partition_name));
945 
946 	num = of_get_property(rootdn, "ibm,partition-no", NULL);
947 	if (num)
948 		partition_number = *num;
949 
950 	of_node_put(rootdn);
951 	return 0;
952 }
953 
954 static struct srp_function_template ibmvstgt_transport_functions = {
955 	.tsk_mgmt_response = ibmvstgt_tsk_mgmt_response,
956 	.it_nexus_response = ibmvstgt_it_nexus_response,
957 };
958 
ibmvstgt_init(void)959 static int __init ibmvstgt_init(void)
960 {
961 	int err = -ENOMEM;
962 
963 	printk("IBM eServer i/pSeries Virtual SCSI Target Driver\n");
964 
965 	ibmvstgt_transport_template =
966 		srp_attach_transport(&ibmvstgt_transport_functions);
967 	if (!ibmvstgt_transport_template)
968 		return err;
969 
970 	vtgtd = create_workqueue("ibmvtgtd");
971 	if (!vtgtd)
972 		goto release_transport;
973 
974 	err = get_system_info();
975 	if (err)
976 		goto destroy_wq;
977 
978 	err = vio_register_driver(&ibmvstgt_driver);
979 	if (err)
980 		goto destroy_wq;
981 
982 	return 0;
983 destroy_wq:
984 	destroy_workqueue(vtgtd);
985 release_transport:
986 	srp_release_transport(ibmvstgt_transport_template);
987 	return err;
988 }
989 
ibmvstgt_exit(void)990 static void __exit ibmvstgt_exit(void)
991 {
992 	printk("Unregister IBM virtual SCSI driver\n");
993 
994 	destroy_workqueue(vtgtd);
995 	vio_unregister_driver(&ibmvstgt_driver);
996 	srp_release_transport(ibmvstgt_transport_template);
997 }
998 
999 MODULE_DESCRIPTION("IBM Virtual SCSI Target");
1000 MODULE_AUTHOR("Santiago Leon");
1001 MODULE_LICENSE("GPL");
1002 
1003 module_init(ibmvstgt_init);
1004 module_exit(ibmvstgt_exit);
1005