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sched/fair: Do not announce throttled next buddy in dequeue_task_fair()
[linux/fpc-iii.git] / drivers / block / sunvdc.c
blob4b911ed96ea3e8ee6996c74299fe8a9d414c1be0
1 /* sunvdc.c: Sun LDOM Virtual Disk Client.
2 *
3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4 */
5
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/blkdev.h>
10 #include <linux/hdreg.h>
11 #include <linux/genhd.h>
12 #include <linux/cdrom.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/completion.h>
16 #include <linux/delay.h>
17 #include <linux/init.h>
18 #include <linux/list.h>
19 #include <linux/scatterlist.h>
20
21 #include <asm/vio.h>
22 #include <asm/ldc.h>
23
24 #define DRV_MODULE_NAME "sunvdc"
25 #define PFX DRV_MODULE_NAME ": "
26 #define DRV_MODULE_VERSION "1.2"
27 #define DRV_MODULE_RELDATE "November 24, 2014"
28
29 static char version[] =
30 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
31 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
32 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
33 MODULE_LICENSE("GPL");
34 MODULE_VERSION(DRV_MODULE_VERSION);
35
36 #define VDC_TX_RING_SIZE 512
37
38 #define WAITING_FOR_LINK_UP 0x01
39 #define WAITING_FOR_TX_SPACE 0x02
40 #define WAITING_FOR_GEN_CMD 0x04
41 #define WAITING_FOR_ANY -1
42
43 static struct workqueue_struct *sunvdc_wq;
44
45 struct vdc_req_entry {
46 struct request *req;
47 };
48
49 struct vdc_port {
50 struct vio_driver_state vio;
51
52 struct gendisk *disk;
53
54 struct vdc_completion *cmp;
55
56 u64 req_id;
57 u64 seq;
58 struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE];
59
60 unsigned long ring_cookies;
61
62 u64 max_xfer_size;
63 u32 vdisk_block_size;
64
65 u64 ldc_timeout;
66 struct timer_list ldc_reset_timer;
67 struct work_struct ldc_reset_work;
68
69 /* The server fills these in for us in the disk attribute
70 * ACK packet.
71 */
72 u64 operations;
73 u32 vdisk_size;
74 u8 vdisk_type;
75 u8 vdisk_mtype;
76
77 char disk_name[32];
78 };
79
80 static void vdc_ldc_reset(struct vdc_port *port);
81 static void vdc_ldc_reset_work(struct work_struct *work);
82 static void vdc_ldc_reset_timer(unsigned long _arg);
83
84 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
85 {
86 return container_of(vio, struct vdc_port, vio);
87 }
88
89 /* Ordered from largest major to lowest */
90 static struct vio_version vdc_versions[] = {
91 { .major = 1, .minor = 1 },
92 { .major = 1, .minor = 0 },
93 };
94
95 static inline int vdc_version_supported(struct vdc_port *port,
96 u16 major, u16 minor)
97 {
98 return port->vio.ver.major == major && port->vio.ver.minor >= minor;
99 }
100
101 #define VDCBLK_NAME "vdisk"
102 static int vdc_major;
103 #define PARTITION_SHIFT 3
104
105 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
106 {
107 return vio_dring_avail(dr, VDC_TX_RING_SIZE);
108 }
109
110 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
111 {
112 struct gendisk *disk = bdev->bd_disk;
113 sector_t nsect = get_capacity(disk);
114 sector_t cylinders = nsect;
115
116 geo->heads = 0xff;
117 geo->sectors = 0x3f;
118 sector_div(cylinders, geo->heads * geo->sectors);
119 geo->cylinders = cylinders;
120 if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect)
121 geo->cylinders = 0xffff;
122
123 return 0;
124 }
125
126 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
127 * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
128 * Needed to be able to install inside an ldom from an iso image.
129 */
130 static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
131 unsigned command, unsigned long argument)
132 {
133 int i;
134 struct gendisk *disk;
135
136 switch (command) {
137 case CDROMMULTISESSION:
138 pr_debug(PFX "Multisession CDs not supported\n");
139 for (i = 0; i < sizeof(struct cdrom_multisession); i++)
140 if (put_user(0, (char __user *)(argument + i)))
141 return -EFAULT;
142 return 0;
143
144 case CDROM_GET_CAPABILITY:
145 disk = bdev->bd_disk;
146
147 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
148 return 0;
149 return -EINVAL;
150
151 default:
152 pr_debug(PFX "ioctl %08x not supported\n", command);
153 return -EINVAL;
154 }
155 }
156
157 static const struct block_device_operations vdc_fops = {
158 .owner = THIS_MODULE,
159 .getgeo = vdc_getgeo,
160 .ioctl = vdc_ioctl,
161 };
162
163 static void vdc_blk_queue_start(struct vdc_port *port)
164 {
165 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
166
167 /* restart blk queue when ring is half emptied. also called after
168 * handshake completes, so check for initial handshake before we've
169 * allocated a disk.
170 */
171 if (port->disk && blk_queue_stopped(port->disk->queue) &&
172 vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50) {
173 blk_start_queue(port->disk->queue);
174 }
175
176 }
177
178 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
179 {
180 if (vio->cmp &&
181 (waiting_for == -1 ||
182 vio->cmp->waiting_for == waiting_for)) {
183 vio->cmp->err = err;
184 complete(&vio->cmp->com);
185 vio->cmp = NULL;
186 }
187 }
188
189 static void vdc_handshake_complete(struct vio_driver_state *vio)
190 {
191 struct vdc_port *port = to_vdc_port(vio);
192
193 del_timer(&port->ldc_reset_timer);
194 vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
195 vdc_blk_queue_start(port);
196 }
197
198 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
199 {
200 struct vio_msg_tag *pkt = arg;
201
202 printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
203 pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
204 printk(KERN_ERR PFX "Resetting connection.\n");
205
206 ldc_disconnect(port->vio.lp);
207
208 return -ECONNRESET;
209 }
210
211 static int vdc_send_attr(struct vio_driver_state *vio)
212 {
213 struct vdc_port *port = to_vdc_port(vio);
214 struct vio_disk_attr_info pkt;
215
216 memset(&pkt, 0, sizeof(pkt));
217
218 pkt.tag.type = VIO_TYPE_CTRL;
219 pkt.tag.stype = VIO_SUBTYPE_INFO;
220 pkt.tag.stype_env = VIO_ATTR_INFO;
221 pkt.tag.sid = vio_send_sid(vio);
222
223 pkt.xfer_mode = VIO_DRING_MODE;
224 pkt.vdisk_block_size = port->vdisk_block_size;
225 pkt.max_xfer_size = port->max_xfer_size;
226
227 viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
228 pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
229
230 return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
231 }
232
233 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
234 {
235 struct vdc_port *port = to_vdc_port(vio);
236 struct vio_disk_attr_info *pkt = arg;
237
238 viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
239 "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
240 pkt->tag.stype, pkt->operations,
241 pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
242 pkt->xfer_mode, pkt->vdisk_block_size,
243 pkt->max_xfer_size);
244
245 if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
246 switch (pkt->vdisk_type) {
247 case VD_DISK_TYPE_DISK:
248 case VD_DISK_TYPE_SLICE:
249 break;
250
251 default:
252 printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
253 vio->name, pkt->vdisk_type);
254 return -ECONNRESET;
255 }
256
257 if (pkt->vdisk_block_size > port->vdisk_block_size) {
258 printk(KERN_ERR PFX "%s: BLOCK size increased "
259 "%u --> %u\n",
260 vio->name,
261 port->vdisk_block_size, pkt->vdisk_block_size);
262 return -ECONNRESET;
263 }
264
265 port->operations = pkt->operations;
266 port->vdisk_type = pkt->vdisk_type;
267 if (vdc_version_supported(port, 1, 1)) {
268 port->vdisk_size = pkt->vdisk_size;
269 port->vdisk_mtype = pkt->vdisk_mtype;
270 }
271 if (pkt->max_xfer_size < port->max_xfer_size)
272 port->max_xfer_size = pkt->max_xfer_size;
273 port->vdisk_block_size = pkt->vdisk_block_size;
274 return 0;
275 } else {
276 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
277
278 return -ECONNRESET;
279 }
280 }
281
282 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
283 {
284 int err = desc->status;
285
286 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
287 }
288
289 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
290 unsigned int index)
291 {
292 struct vio_disk_desc *desc = vio_dring_entry(dr, index);
293 struct vdc_req_entry *rqe = &port->rq_arr[index];
294 struct request *req;
295
296 if (unlikely(desc->hdr.state != VIO_DESC_DONE))
297 return;
298
299 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
300 desc->hdr.state = VIO_DESC_FREE;
301 dr->cons = vio_dring_next(dr, index);
302
303 req = rqe->req;
304 if (req == NULL) {
305 vdc_end_special(port, desc);
306 return;
307 }
308
309 rqe->req = NULL;
310
311 __blk_end_request(req, (desc->status ? -EIO : 0), desc->size);
312
313 vdc_blk_queue_start(port);
314 }
315
316 static int vdc_ack(struct vdc_port *port, void *msgbuf)
317 {
318 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
319 struct vio_dring_data *pkt = msgbuf;
320
321 if (unlikely(pkt->dring_ident != dr->ident ||
322 pkt->start_idx != pkt->end_idx ||
323 pkt->start_idx >= VDC_TX_RING_SIZE))
324 return 0;
325
326 vdc_end_one(port, dr, pkt->start_idx);
327
328 return 0;
329 }
330
331 static int vdc_nack(struct vdc_port *port, void *msgbuf)
332 {
333 /* XXX Implement me XXX */
334 return 0;
335 }
336
337 static void vdc_event(void *arg, int event)
338 {
339 struct vdc_port *port = arg;
340 struct vio_driver_state *vio = &port->vio;
341 unsigned long flags;
342 int err;
343
344 spin_lock_irqsave(&vio->lock, flags);
345
346 if (unlikely(event == LDC_EVENT_RESET)) {
347 vio_link_state_change(vio, event);
348 queue_work(sunvdc_wq, &port->ldc_reset_work);
349 goto out;
350 }
351
352 if (unlikely(event == LDC_EVENT_UP)) {
353 vio_link_state_change(vio, event);
354 goto out;
355 }
356
357 if (unlikely(event != LDC_EVENT_DATA_READY)) {
358 pr_warn(PFX "Unexpected LDC event %d\n", event);
359 goto out;
360 }
361
362 err = 0;
363 while (1) {
364 union {
365 struct vio_msg_tag tag;
366 u64 raw[8];
367 } msgbuf;
368
369 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
370 if (unlikely(err < 0)) {
371 if (err == -ECONNRESET)
372 vio_conn_reset(vio);
373 break;
374 }
375 if (err == 0)
376 break;
377 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
378 msgbuf.tag.type,
379 msgbuf.tag.stype,
380 msgbuf.tag.stype_env,
381 msgbuf.tag.sid);
382 err = vio_validate_sid(vio, &msgbuf.tag);
383 if (err < 0)
384 break;
385
386 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
387 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
388 err = vdc_ack(port, &msgbuf);
389 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
390 err = vdc_nack(port, &msgbuf);
391 else
392 err = vdc_handle_unknown(port, &msgbuf);
393 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
394 err = vio_control_pkt_engine(vio, &msgbuf);
395 } else {
396 err = vdc_handle_unknown(port, &msgbuf);
397 }
398 if (err < 0)
399 break;
400 }
401 if (err < 0)
402 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
403 out:
404 spin_unlock_irqrestore(&vio->lock, flags);
405 }
406
407 static int __vdc_tx_trigger(struct vdc_port *port)
408 {
409 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
410 struct vio_dring_data hdr = {
411 .tag = {
412 .type = VIO_TYPE_DATA,
413 .stype = VIO_SUBTYPE_INFO,
414 .stype_env = VIO_DRING_DATA,
415 .sid = vio_send_sid(&port->vio),
416 },
417 .dring_ident = dr->ident,
418 .start_idx = dr->prod,
419 .end_idx = dr->prod,
420 };
421 int err, delay;
422
423 hdr.seq = dr->snd_nxt;
424 delay = 1;
425 do {
426 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
427 if (err > 0) {
428 dr->snd_nxt++;
429 break;
430 }
431 udelay(delay);
432 if ((delay <<= 1) > 128)
433 delay = 128;
434 } while (err == -EAGAIN);
435
436 if (err == -ENOTCONN)
437 vdc_ldc_reset(port);
438 return err;
439 }
440
441 static int __send_request(struct request *req)
442 {
443 struct vdc_port *port = req->rq_disk->private_data;
444 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
445 struct scatterlist sg[port->ring_cookies];
446 struct vdc_req_entry *rqe;
447 struct vio_disk_desc *desc;
448 unsigned int map_perm;
449 int nsg, err, i;
450 u64 len;
451 u8 op;
452
453 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
454
455 if (rq_data_dir(req) == READ) {
456 map_perm |= LDC_MAP_W;
457 op = VD_OP_BREAD;
458 } else {
459 map_perm |= LDC_MAP_R;
460 op = VD_OP_BWRITE;
461 }
462
463 sg_init_table(sg, port->ring_cookies);
464 nsg = blk_rq_map_sg(req->q, req, sg);
465
466 len = 0;
467 for (i = 0; i < nsg; i++)
468 len += sg[i].length;
469
470 desc = vio_dring_cur(dr);
471
472 err = ldc_map_sg(port->vio.lp, sg, nsg,
473 desc->cookies, port->ring_cookies,
474 map_perm);
475 if (err < 0) {
476 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
477 return err;
478 }
479
480 rqe = &port->rq_arr[dr->prod];
481 rqe->req = req;
482
483 desc->hdr.ack = VIO_ACK_ENABLE;
484 desc->req_id = port->req_id;
485 desc->operation = op;
486 if (port->vdisk_type == VD_DISK_TYPE_DISK) {
487 desc->slice = 0xff;
488 } else {
489 desc->slice = 0;
490 }
491 desc->status = ~0;
492 desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
493 desc->size = len;
494 desc->ncookies = err;
495
496 /* This has to be a non-SMP write barrier because we are writing
497 * to memory which is shared with the peer LDOM.
498 */
499 wmb();
500 desc->hdr.state = VIO_DESC_READY;
501
502 err = __vdc_tx_trigger(port);
503 if (err < 0) {
504 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
505 } else {
506 port->req_id++;
507 dr->prod = vio_dring_next(dr, dr->prod);
508 }
509
510 return err;
511 }
512
513 static void do_vdc_request(struct request_queue *rq)
514 {
515 struct request *req;
516
517 while ((req = blk_peek_request(rq)) != NULL) {
518 struct vdc_port *port;
519 struct vio_dring_state *dr;
520
521 port = req->rq_disk->private_data;
522 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
523 if (unlikely(vdc_tx_dring_avail(dr) < 1))
524 goto wait;
525
526 blk_start_request(req);
527
528 if (__send_request(req) < 0) {
529 blk_requeue_request(rq, req);
530 wait:
531 /* Avoid pointless unplugs. */
532 blk_stop_queue(rq);
533 break;
534 }
535 }
536 }
537
538 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
539 {
540 struct vio_dring_state *dr;
541 struct vio_completion comp;
542 struct vio_disk_desc *desc;
543 unsigned int map_perm;
544 unsigned long flags;
545 int op_len, err;
546 void *req_buf;
547
548 if (!(((u64)1 << (u64)op) & port->operations))
549 return -EOPNOTSUPP;
550
551 switch (op) {
552 case VD_OP_BREAD:
553 case VD_OP_BWRITE:
554 default:
555 return -EINVAL;
556
557 case VD_OP_FLUSH:
558 op_len = 0;
559 map_perm = 0;
560 break;
561
562 case VD_OP_GET_WCE:
563 op_len = sizeof(u32);
564 map_perm = LDC_MAP_W;
565 break;
566
567 case VD_OP_SET_WCE:
568 op_len = sizeof(u32);
569 map_perm = LDC_MAP_R;
570 break;
571
572 case VD_OP_GET_VTOC:
573 op_len = sizeof(struct vio_disk_vtoc);
574 map_perm = LDC_MAP_W;
575 break;
576
577 case VD_OP_SET_VTOC:
578 op_len = sizeof(struct vio_disk_vtoc);
579 map_perm = LDC_MAP_R;
580 break;
581
582 case VD_OP_GET_DISKGEOM:
583 op_len = sizeof(struct vio_disk_geom);
584 map_perm = LDC_MAP_W;
585 break;
586
587 case VD_OP_SET_DISKGEOM:
588 op_len = sizeof(struct vio_disk_geom);
589 map_perm = LDC_MAP_R;
590 break;
591
592 case VD_OP_SCSICMD:
593 op_len = 16;
594 map_perm = LDC_MAP_RW;
595 break;
596
597 case VD_OP_GET_DEVID:
598 op_len = sizeof(struct vio_disk_devid);
599 map_perm = LDC_MAP_W;
600 break;
601
602 case VD_OP_GET_EFI:
603 case VD_OP_SET_EFI:
604 return -EOPNOTSUPP;
605 break;
606 };
607
608 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
609
610 op_len = (op_len + 7) & ~7;
611 req_buf = kzalloc(op_len, GFP_KERNEL);
612 if (!req_buf)
613 return -ENOMEM;
614
615 if (len > op_len)
616 len = op_len;
617
618 if (map_perm & LDC_MAP_R)
619 memcpy(req_buf, buf, len);
620
621 spin_lock_irqsave(&port->vio.lock, flags);
622
623 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
624
625 /* XXX If we want to use this code generically we have to
626 * XXX handle TX ring exhaustion etc.
627 */
628 desc = vio_dring_cur(dr);
629
630 err = ldc_map_single(port->vio.lp, req_buf, op_len,
631 desc->cookies, port->ring_cookies,
632 map_perm);
633 if (err < 0) {
634 spin_unlock_irqrestore(&port->vio.lock, flags);
635 kfree(req_buf);
636 return err;
637 }
638
639 init_completion(&comp.com);
640 comp.waiting_for = WAITING_FOR_GEN_CMD;
641 port->vio.cmp = &comp;
642
643 desc->hdr.ack = VIO_ACK_ENABLE;
644 desc->req_id = port->req_id;
645 desc->operation = op;
646 desc->slice = 0;
647 desc->status = ~0;
648 desc->offset = 0;
649 desc->size = op_len;
650 desc->ncookies = err;
651
652 /* This has to be a non-SMP write barrier because we are writing
653 * to memory which is shared with the peer LDOM.
654 */
655 wmb();
656 desc->hdr.state = VIO_DESC_READY;
657
658 err = __vdc_tx_trigger(port);
659 if (err >= 0) {
660 port->req_id++;
661 dr->prod = vio_dring_next(dr, dr->prod);
662 spin_unlock_irqrestore(&port->vio.lock, flags);
663
664 wait_for_completion(&comp.com);
665 err = comp.err;
666 } else {
667 port->vio.cmp = NULL;
668 spin_unlock_irqrestore(&port->vio.lock, flags);
669 }
670
671 if (map_perm & LDC_MAP_W)
672 memcpy(buf, req_buf, len);
673
674 kfree(req_buf);
675
676 return err;
677 }
678
679 static int vdc_alloc_tx_ring(struct vdc_port *port)
680 {
681 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
682 unsigned long len, entry_size;
683 int ncookies;
684 void *dring;
685
686 entry_size = sizeof(struct vio_disk_desc) +
687 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
688 len = (VDC_TX_RING_SIZE * entry_size);
689
690 ncookies = VIO_MAX_RING_COOKIES;
691 dring = ldc_alloc_exp_dring(port->vio.lp, len,
692 dr->cookies, &ncookies,
693 (LDC_MAP_SHADOW |
694 LDC_MAP_DIRECT |
695 LDC_MAP_RW));
696 if (IS_ERR(dring))
697 return PTR_ERR(dring);
698
699 dr->base = dring;
700 dr->entry_size = entry_size;
701 dr->num_entries = VDC_TX_RING_SIZE;
702 dr->prod = dr->cons = 0;
703 dr->pending = VDC_TX_RING_SIZE;
704 dr->ncookies = ncookies;
705
706 return 0;
707 }
708
709 static void vdc_free_tx_ring(struct vdc_port *port)
710 {
711 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
712
713 if (dr->base) {
714 ldc_free_exp_dring(port->vio.lp, dr->base,
715 (dr->entry_size * dr->num_entries),
716 dr->cookies, dr->ncookies);
717 dr->base = NULL;
718 dr->entry_size = 0;
719 dr->num_entries = 0;
720 dr->pending = 0;
721 dr->ncookies = 0;
722 }
723 }
724
725 static int vdc_port_up(struct vdc_port *port)
726 {
727 struct vio_completion comp;
728
729 init_completion(&comp.com);
730 comp.err = 0;
731 comp.waiting_for = WAITING_FOR_LINK_UP;
732 port->vio.cmp = &comp;
733
734 vio_port_up(&port->vio);
735 wait_for_completion(&comp.com);
736 return comp.err;
737 }
738
739 static void vdc_port_down(struct vdc_port *port)
740 {
741 ldc_disconnect(port->vio.lp);
742 ldc_unbind(port->vio.lp);
743 vdc_free_tx_ring(port);
744 vio_ldc_free(&port->vio);
745 }
746
747 static int probe_disk(struct vdc_port *port)
748 {
749 struct request_queue *q;
750 struct gendisk *g;
751 int err;
752
753 err = vdc_port_up(port);
754 if (err)
755 return err;
756
757 if (vdc_version_supported(port, 1, 1)) {
758 /* vdisk_size should be set during the handshake, if it wasn't
759 * then the underlying disk is reserved by another system
760 */
761 if (port->vdisk_size == -1)
762 return -ENODEV;
763 } else {
764 struct vio_disk_geom geom;
765
766 err = generic_request(port, VD_OP_GET_DISKGEOM,
767 &geom, sizeof(geom));
768 if (err < 0) {
769 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
770 "error %d\n", err);
771 return err;
772 }
773 port->vdisk_size = ((u64)geom.num_cyl *
774 (u64)geom.num_hd *
775 (u64)geom.num_sec);
776 }
777
778 q = blk_init_queue(do_vdc_request, &port->vio.lock);
779 if (!q) {
780 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
781 port->vio.name);
782 return -ENOMEM;
783 }
784 g = alloc_disk(1 << PARTITION_SHIFT);
785 if (!g) {
786 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
787 port->vio.name);
788 blk_cleanup_queue(q);
789 return -ENOMEM;
790 }
791
792 port->disk = g;
793
794 /* Each segment in a request is up to an aligned page in size. */
795 blk_queue_segment_boundary(q, PAGE_SIZE - 1);
796 blk_queue_max_segment_size(q, PAGE_SIZE);
797
798 blk_queue_max_segments(q, port->ring_cookies);
799 blk_queue_max_hw_sectors(q, port->max_xfer_size);
800 g->major = vdc_major;
801 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
802 strcpy(g->disk_name, port->disk_name);
803
804 g->fops = &vdc_fops;
805 g->queue = q;
806 g->private_data = port;
807 g->driverfs_dev = &port->vio.vdev->dev;
808
809 set_capacity(g, port->vdisk_size);
810
811 if (vdc_version_supported(port, 1, 1)) {
812 switch (port->vdisk_mtype) {
813 case VD_MEDIA_TYPE_CD:
814 pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
815 g->flags |= GENHD_FL_CD;
816 g->flags |= GENHD_FL_REMOVABLE;
817 set_disk_ro(g, 1);
818 break;
819
820 case VD_MEDIA_TYPE_DVD:
821 pr_info(PFX "Virtual DVD %s\n", port->disk_name);
822 g->flags |= GENHD_FL_CD;
823 g->flags |= GENHD_FL_REMOVABLE;
824 set_disk_ro(g, 1);
825 break;
826
827 case VD_MEDIA_TYPE_FIXED:
828 pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
829 break;
830 }
831 }
832
833 pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
834 g->disk_name,
835 port->vdisk_size, (port->vdisk_size >> (20 - 9)),
836 port->vio.ver.major, port->vio.ver.minor);
837
838 add_disk(g);
839
840 return 0;
841 }
842
843 static struct ldc_channel_config vdc_ldc_cfg = {
844 .event = vdc_event,
845 .mtu = 64,
846 .mode = LDC_MODE_UNRELIABLE,
847 };
848
849 static struct vio_driver_ops vdc_vio_ops = {
850 .send_attr = vdc_send_attr,
851 .handle_attr = vdc_handle_attr,
852 .handshake_complete = vdc_handshake_complete,
853 };
854
855 static void print_version(void)
856 {
857 static int version_printed;
858
859 if (version_printed++ == 0)
860 printk(KERN_INFO "%s", version);
861 }
862
863 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
864 {
865 struct mdesc_handle *hp;
866 struct vdc_port *port;
867 int err;
868 const u64 *ldc_timeout;
869
870 print_version();
871
872 hp = mdesc_grab();
873
874 err = -ENODEV;
875 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
876 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
877 vdev->dev_no);
878 goto err_out_release_mdesc;
879 }
880
881 port = kzalloc(sizeof(*port), GFP_KERNEL);
882 err = -ENOMEM;
883 if (!port) {
884 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
885 goto err_out_release_mdesc;
886 }
887
888 if (vdev->dev_no >= 26)
889 snprintf(port->disk_name, sizeof(port->disk_name),
890 VDCBLK_NAME "%c%c",
891 'a' + ((int)vdev->dev_no / 26) - 1,
892 'a' + ((int)vdev->dev_no % 26));
893 else
894 snprintf(port->disk_name, sizeof(port->disk_name),
895 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
896 port->vdisk_size = -1;
897
898 /* Actual wall time may be double due to do_generic_file_read() doing
899 * a readahead I/O first, and once that fails it will try to read a
900 * single page.
901 */
902 ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
903 port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
904 setup_timer(&port->ldc_reset_timer, vdc_ldc_reset_timer,
905 (unsigned long)port);
906 INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
907
908 err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
909 vdc_versions, ARRAY_SIZE(vdc_versions),
910 &vdc_vio_ops, port->disk_name);
911 if (err)
912 goto err_out_free_port;
913
914 port->vdisk_block_size = 512;
915 port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
916 port->ring_cookies = ((port->max_xfer_size *
917 port->vdisk_block_size) / PAGE_SIZE) + 2;
918
919 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
920 if (err)
921 goto err_out_free_port;
922
923 err = vdc_alloc_tx_ring(port);
924 if (err)
925 goto err_out_free_ldc;
926
927 err = probe_disk(port);
928 if (err)
929 goto err_out_free_tx_ring;
930
931 dev_set_drvdata(&vdev->dev, port);
932
933 mdesc_release(hp);
934
935 return 0;
936
937 err_out_free_tx_ring:
938 vdc_free_tx_ring(port);
939
940 err_out_free_ldc:
941 vio_ldc_free(&port->vio);
942
943 err_out_free_port:
944 kfree(port);
945
946 err_out_release_mdesc:
947 mdesc_release(hp);
948 return err;
949 }
950
951 static int vdc_port_remove(struct vio_dev *vdev)
952 {
953 struct vdc_port *port = dev_get_drvdata(&vdev->dev);
954
955 if (port) {
956 unsigned long flags;
957
958 spin_lock_irqsave(&port->vio.lock, flags);
959 blk_stop_queue(port->disk->queue);
960 spin_unlock_irqrestore(&port->vio.lock, flags);
961
962 flush_work(&port->ldc_reset_work);
963 del_timer_sync(&port->ldc_reset_timer);
964 del_timer_sync(&port->vio.timer);
965
966 del_gendisk(port->disk);
967 blk_cleanup_queue(port->disk->queue);
968 put_disk(port->disk);
969 port->disk = NULL;
970
971 vdc_free_tx_ring(port);
972 vio_ldc_free(&port->vio);
973
974 dev_set_drvdata(&vdev->dev, NULL);
975
976 kfree(port);
977 }
978 return 0;
979 }
980
981 static void vdc_requeue_inflight(struct vdc_port *port)
982 {
983 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
984 u32 idx;
985
986 for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) {
987 struct vio_disk_desc *desc = vio_dring_entry(dr, idx);
988 struct vdc_req_entry *rqe = &port->rq_arr[idx];
989 struct request *req;
990
991 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
992 desc->hdr.state = VIO_DESC_FREE;
993 dr->cons = vio_dring_next(dr, idx);
994
995 req = rqe->req;
996 if (req == NULL) {
997 vdc_end_special(port, desc);
998 continue;
999 }
1000
1001 rqe->req = NULL;
1002 blk_requeue_request(port->disk->queue, req);
1003 }
1004 }
1005
1006 static void vdc_queue_drain(struct vdc_port *port)
1007 {
1008 struct request *req;
1009
1010 while ((req = blk_fetch_request(port->disk->queue)) != NULL)
1011 __blk_end_request_all(req, -EIO);
1012 }
1013
1014 static void vdc_ldc_reset_timer(unsigned long _arg)
1015 {
1016 struct vdc_port *port = (struct vdc_port *) _arg;
1017 struct vio_driver_state *vio = &port->vio;
1018 unsigned long flags;
1019
1020 spin_lock_irqsave(&vio->lock, flags);
1021 if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
1022 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
1023 port->disk_name, port->ldc_timeout);
1024 vdc_queue_drain(port);
1025 vdc_blk_queue_start(port);
1026 }
1027 spin_unlock_irqrestore(&vio->lock, flags);
1028 }
1029
1030 static void vdc_ldc_reset_work(struct work_struct *work)
1031 {
1032 struct vdc_port *port;
1033 struct vio_driver_state *vio;
1034 unsigned long flags;
1035
1036 port = container_of(work, struct vdc_port, ldc_reset_work);
1037 vio = &port->vio;
1038
1039 spin_lock_irqsave(&vio->lock, flags);
1040 vdc_ldc_reset(port);
1041 spin_unlock_irqrestore(&vio->lock, flags);
1042 }
1043
1044 static void vdc_ldc_reset(struct vdc_port *port)
1045 {
1046 int err;
1047
1048 assert_spin_locked(&port->vio.lock);
1049
1050 pr_warn(PFX "%s ldc link reset\n", port->disk_name);
1051 blk_stop_queue(port->disk->queue);
1052 vdc_requeue_inflight(port);
1053 vdc_port_down(port);
1054
1055 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1056 if (err) {
1057 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err);
1058 return;
1059 }
1060
1061 err = vdc_alloc_tx_ring(port);
1062 if (err) {
1063 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err);
1064 goto err_free_ldc;
1065 }
1066
1067 if (port->ldc_timeout)
1068 mod_timer(&port->ldc_reset_timer,
1069 round_jiffies(jiffies + HZ * port->ldc_timeout));
1070 mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
1071 return;
1072
1073 err_free_ldc:
1074 vio_ldc_free(&port->vio);
1075 }
1076
1077 static const struct vio_device_id vdc_port_match[] = {
1078 {
1079 .type = "vdc-port",
1080 },
1081 {},
1082 };
1083 MODULE_DEVICE_TABLE(vio, vdc_port_match);
1084
1085 static struct vio_driver vdc_port_driver = {
1086 .id_table = vdc_port_match,
1087 .probe = vdc_port_probe,
1088 .remove = vdc_port_remove,
1089 .name = "vdc_port",
1090 };
1091
1092 static int __init vdc_init(void)
1093 {
1094 int err;
1095
1096 sunvdc_wq = alloc_workqueue("sunvdc", 0, 0);
1097 if (!sunvdc_wq)
1098 return -ENOMEM;
1099
1100 err = register_blkdev(0, VDCBLK_NAME);
1101 if (err < 0)
1102 goto out_free_wq;
1103
1104 vdc_major = err;
1105
1106 err = vio_register_driver(&vdc_port_driver);
1107 if (err)
1108 goto out_unregister_blkdev;
1109
1110 return 0;
1111
1112 out_unregister_blkdev:
1113 unregister_blkdev(vdc_major, VDCBLK_NAME);
1114 vdc_major = 0;
1115
1116 out_free_wq:
1117 destroy_workqueue(sunvdc_wq);
1118 return err;
1119 }
1120
1121 static void __exit vdc_exit(void)
1122 {
1123 vio_unregister_driver(&vdc_port_driver);
1124 unregister_blkdev(vdc_major, VDCBLK_NAME);
1125 destroy_workqueue(sunvdc_wq);
1126 }
1127
1128 module_init(vdc_init);
1129 module_exit(vdc_exit);
Linux with added FPC-III support