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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / block / sunvdc.c
blob39aeebc6837da36fda3bd9ca6fb2f5fb0a13704f
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* sunvdc.c: Sun LDOM Virtual Disk Client.
3 *
4 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
5 */
6
7 #include <linux/module.h>
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 #include <linux/blk-mq.h>
11 #include <linux/hdreg.h>
12 #include <linux/genhd.h>
13 #include <linux/cdrom.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/completion.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/list.h>
20 #include <linux/scatterlist.h>
21
22 #include <asm/vio.h>
23 #include <asm/ldc.h>
24
25 #define DRV_MODULE_NAME "sunvdc"
26 #define PFX DRV_MODULE_NAME ": "
27 #define DRV_MODULE_VERSION "1.2"
28 #define DRV_MODULE_RELDATE "November 24, 2014"
29
30 static char version[] =
31 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
32 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
33 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
34 MODULE_LICENSE("GPL");
35 MODULE_VERSION(DRV_MODULE_VERSION);
36
37 #define VDC_TX_RING_SIZE 512
38 #define VDC_DEFAULT_BLK_SIZE 512
39
40 #define MAX_XFER_BLKS (128 * 1024)
41 #define MAX_XFER_SIZE (MAX_XFER_BLKS / VDC_DEFAULT_BLK_SIZE)
42 #define MAX_RING_COOKIES ((MAX_XFER_BLKS / PAGE_SIZE) + 2)
43
44 #define WAITING_FOR_LINK_UP 0x01
45 #define WAITING_FOR_TX_SPACE 0x02
46 #define WAITING_FOR_GEN_CMD 0x04
47 #define WAITING_FOR_ANY -1
48
49 #define VDC_MAX_RETRIES 10
50
51 static struct workqueue_struct *sunvdc_wq;
52
53 struct vdc_req_entry {
54 struct request *req;
55 };
56
57 struct vdc_port {
58 struct vio_driver_state vio;
59
60 struct gendisk *disk;
61
62 struct vdc_completion *cmp;
63
64 u64 req_id;
65 u64 seq;
66 struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE];
67
68 unsigned long ring_cookies;
69
70 u64 max_xfer_size;
71 u32 vdisk_block_size;
72 u32 drain;
73
74 u64 ldc_timeout;
75 struct delayed_work ldc_reset_timer_work;
76 struct work_struct ldc_reset_work;
77
78 /* The server fills these in for us in the disk attribute
79 * ACK packet.
80 */
81 u64 operations;
82 u32 vdisk_size;
83 u8 vdisk_type;
84 u8 vdisk_mtype;
85 u32 vdisk_phys_blksz;
86
87 struct blk_mq_tag_set tag_set;
88
89 char disk_name[32];
90 };
91
92 static void vdc_ldc_reset(struct vdc_port *port);
93 static void vdc_ldc_reset_work(struct work_struct *work);
94 static void vdc_ldc_reset_timer_work(struct work_struct *work);
95
96 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
97 {
98 return container_of(vio, struct vdc_port, vio);
99 }
100
101 /* Ordered from largest major to lowest */
102 static struct vio_version vdc_versions[] = {
103 { .major = 1, .minor = 2 },
104 { .major = 1, .minor = 1 },
105 { .major = 1, .minor = 0 },
106 };
107
108 static inline int vdc_version_supported(struct vdc_port *port,
109 u16 major, u16 minor)
110 {
111 return port->vio.ver.major == major && port->vio.ver.minor >= minor;
112 }
113
114 #define VDCBLK_NAME "vdisk"
115 static int vdc_major;
116 #define PARTITION_SHIFT 3
117
118 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
119 {
120 return vio_dring_avail(dr, VDC_TX_RING_SIZE);
121 }
122
123 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
124 {
125 struct gendisk *disk = bdev->bd_disk;
126 sector_t nsect = get_capacity(disk);
127 sector_t cylinders = nsect;
128
129 geo->heads = 0xff;
130 geo->sectors = 0x3f;
131 sector_div(cylinders, geo->heads * geo->sectors);
132 geo->cylinders = cylinders;
133 if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect)
134 geo->cylinders = 0xffff;
135
136 return 0;
137 }
138
139 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
140 * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
141 * Needed to be able to install inside an ldom from an iso image.
142 */
143 static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
144 unsigned command, unsigned long argument)
145 {
146 int i;
147 struct gendisk *disk;
148
149 switch (command) {
150 case CDROMMULTISESSION:
151 pr_debug(PFX "Multisession CDs not supported\n");
152 for (i = 0; i < sizeof(struct cdrom_multisession); i++)
153 if (put_user(0, (char __user *)(argument + i)))
154 return -EFAULT;
155 return 0;
156
157 case CDROM_GET_CAPABILITY:
158 disk = bdev->bd_disk;
159
160 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
161 return 0;
162 return -EINVAL;
163
164 default:
165 pr_debug(PFX "ioctl %08x not supported\n", command);
166 return -EINVAL;
167 }
168 }
169
170 static const struct block_device_operations vdc_fops = {
171 .owner = THIS_MODULE,
172 .getgeo = vdc_getgeo,
173 .ioctl = vdc_ioctl,
174 .compat_ioctl = blkdev_compat_ptr_ioctl,
175 };
176
177 static void vdc_blk_queue_start(struct vdc_port *port)
178 {
179 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
180
181 /* restart blk queue when ring is half emptied. also called after
182 * handshake completes, so check for initial handshake before we've
183 * allocated a disk.
184 */
185 if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
186 blk_mq_start_stopped_hw_queues(port->disk->queue, true);
187 }
188
189 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
190 {
191 if (vio->cmp &&
192 (waiting_for == -1 ||
193 vio->cmp->waiting_for == waiting_for)) {
194 vio->cmp->err = err;
195 complete(&vio->cmp->com);
196 vio->cmp = NULL;
197 }
198 }
199
200 static void vdc_handshake_complete(struct vio_driver_state *vio)
201 {
202 struct vdc_port *port = to_vdc_port(vio);
203
204 cancel_delayed_work(&port->ldc_reset_timer_work);
205 vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
206 vdc_blk_queue_start(port);
207 }
208
209 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
210 {
211 struct vio_msg_tag *pkt = arg;
212
213 printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
214 pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
215 printk(KERN_ERR PFX "Resetting connection.\n");
216
217 ldc_disconnect(port->vio.lp);
218
219 return -ECONNRESET;
220 }
221
222 static int vdc_send_attr(struct vio_driver_state *vio)
223 {
224 struct vdc_port *port = to_vdc_port(vio);
225 struct vio_disk_attr_info pkt;
226
227 memset(&pkt, 0, sizeof(pkt));
228
229 pkt.tag.type = VIO_TYPE_CTRL;
230 pkt.tag.stype = VIO_SUBTYPE_INFO;
231 pkt.tag.stype_env = VIO_ATTR_INFO;
232 pkt.tag.sid = vio_send_sid(vio);
233
234 pkt.xfer_mode = VIO_DRING_MODE;
235 pkt.vdisk_block_size = port->vdisk_block_size;
236 pkt.max_xfer_size = port->max_xfer_size;
237
238 viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
239 pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
240
241 return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
242 }
243
244 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
245 {
246 struct vdc_port *port = to_vdc_port(vio);
247 struct vio_disk_attr_info *pkt = arg;
248
249 viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
250 "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
251 pkt->tag.stype, pkt->operations,
252 pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
253 pkt->xfer_mode, pkt->vdisk_block_size,
254 pkt->max_xfer_size);
255
256 if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
257 switch (pkt->vdisk_type) {
258 case VD_DISK_TYPE_DISK:
259 case VD_DISK_TYPE_SLICE:
260 break;
261
262 default:
263 printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
264 vio->name, pkt->vdisk_type);
265 return -ECONNRESET;
266 }
267
268 if (pkt->vdisk_block_size > port->vdisk_block_size) {
269 printk(KERN_ERR PFX "%s: BLOCK size increased "
270 "%u --> %u\n",
271 vio->name,
272 port->vdisk_block_size, pkt->vdisk_block_size);
273 return -ECONNRESET;
274 }
275
276 port->operations = pkt->operations;
277 port->vdisk_type = pkt->vdisk_type;
278 if (vdc_version_supported(port, 1, 1)) {
279 port->vdisk_size = pkt->vdisk_size;
280 port->vdisk_mtype = pkt->vdisk_mtype;
281 }
282 if (pkt->max_xfer_size < port->max_xfer_size)
283 port->max_xfer_size = pkt->max_xfer_size;
284 port->vdisk_block_size = pkt->vdisk_block_size;
285
286 port->vdisk_phys_blksz = VDC_DEFAULT_BLK_SIZE;
287 if (vdc_version_supported(port, 1, 2))
288 port->vdisk_phys_blksz = pkt->phys_block_size;
289
290 return 0;
291 } else {
292 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
293
294 return -ECONNRESET;
295 }
296 }
297
298 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
299 {
300 int err = desc->status;
301
302 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
303 }
304
305 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
306 unsigned int index)
307 {
308 struct vio_disk_desc *desc = vio_dring_entry(dr, index);
309 struct vdc_req_entry *rqe = &port->rq_arr[index];
310 struct request *req;
311
312 if (unlikely(desc->hdr.state != VIO_DESC_DONE))
313 return;
314
315 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
316 desc->hdr.state = VIO_DESC_FREE;
317 dr->cons = vio_dring_next(dr, index);
318
319 req = rqe->req;
320 if (req == NULL) {
321 vdc_end_special(port, desc);
322 return;
323 }
324
325 rqe->req = NULL;
326
327 blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0);
328
329 vdc_blk_queue_start(port);
330 }
331
332 static int vdc_ack(struct vdc_port *port, void *msgbuf)
333 {
334 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
335 struct vio_dring_data *pkt = msgbuf;
336
337 if (unlikely(pkt->dring_ident != dr->ident ||
338 pkt->start_idx != pkt->end_idx ||
339 pkt->start_idx >= VDC_TX_RING_SIZE))
340 return 0;
341
342 vdc_end_one(port, dr, pkt->start_idx);
343
344 return 0;
345 }
346
347 static int vdc_nack(struct vdc_port *port, void *msgbuf)
348 {
349 /* XXX Implement me XXX */
350 return 0;
351 }
352
353 static void vdc_event(void *arg, int event)
354 {
355 struct vdc_port *port = arg;
356 struct vio_driver_state *vio = &port->vio;
357 unsigned long flags;
358 int err;
359
360 spin_lock_irqsave(&vio->lock, flags);
361
362 if (unlikely(event == LDC_EVENT_RESET)) {
363 vio_link_state_change(vio, event);
364 queue_work(sunvdc_wq, &port->ldc_reset_work);
365 goto out;
366 }
367
368 if (unlikely(event == LDC_EVENT_UP)) {
369 vio_link_state_change(vio, event);
370 goto out;
371 }
372
373 if (unlikely(event != LDC_EVENT_DATA_READY)) {
374 pr_warn(PFX "Unexpected LDC event %d\n", event);
375 goto out;
376 }
377
378 err = 0;
379 while (1) {
380 union {
381 struct vio_msg_tag tag;
382 u64 raw[8];
383 } msgbuf;
384
385 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
386 if (unlikely(err < 0)) {
387 if (err == -ECONNRESET)
388 vio_conn_reset(vio);
389 break;
390 }
391 if (err == 0)
392 break;
393 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
394 msgbuf.tag.type,
395 msgbuf.tag.stype,
396 msgbuf.tag.stype_env,
397 msgbuf.tag.sid);
398 err = vio_validate_sid(vio, &msgbuf.tag);
399 if (err < 0)
400 break;
401
402 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
403 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
404 err = vdc_ack(port, &msgbuf);
405 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
406 err = vdc_nack(port, &msgbuf);
407 else
408 err = vdc_handle_unknown(port, &msgbuf);
409 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
410 err = vio_control_pkt_engine(vio, &msgbuf);
411 } else {
412 err = vdc_handle_unknown(port, &msgbuf);
413 }
414 if (err < 0)
415 break;
416 }
417 if (err < 0)
418 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
419 out:
420 spin_unlock_irqrestore(&vio->lock, flags);
421 }
422
423 static int __vdc_tx_trigger(struct vdc_port *port)
424 {
425 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
426 struct vio_dring_data hdr = {
427 .tag = {
428 .type = VIO_TYPE_DATA,
429 .stype = VIO_SUBTYPE_INFO,
430 .stype_env = VIO_DRING_DATA,
431 .sid = vio_send_sid(&port->vio),
432 },
433 .dring_ident = dr->ident,
434 .start_idx = dr->prod,
435 .end_idx = dr->prod,
436 };
437 int err, delay;
438 int retries = 0;
439
440 hdr.seq = dr->snd_nxt;
441 delay = 1;
442 do {
443 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
444 if (err > 0) {
445 dr->snd_nxt++;
446 break;
447 }
448 udelay(delay);
449 if ((delay <<= 1) > 128)
450 delay = 128;
451 if (retries++ > VDC_MAX_RETRIES)
452 break;
453 } while (err == -EAGAIN);
454
455 if (err == -ENOTCONN)
456 vdc_ldc_reset(port);
457 return err;
458 }
459
460 static int __send_request(struct request *req)
461 {
462 struct vdc_port *port = req->rq_disk->private_data;
463 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
464 struct scatterlist sg[MAX_RING_COOKIES];
465 struct vdc_req_entry *rqe;
466 struct vio_disk_desc *desc;
467 unsigned int map_perm;
468 int nsg, err, i;
469 u64 len;
470 u8 op;
471
472 if (WARN_ON(port->ring_cookies > MAX_RING_COOKIES))
473 return -EINVAL;
474
475 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
476
477 if (rq_data_dir(req) == READ) {
478 map_perm |= LDC_MAP_W;
479 op = VD_OP_BREAD;
480 } else {
481 map_perm |= LDC_MAP_R;
482 op = VD_OP_BWRITE;
483 }
484
485 sg_init_table(sg, port->ring_cookies);
486 nsg = blk_rq_map_sg(req->q, req, sg);
487
488 len = 0;
489 for (i = 0; i < nsg; i++)
490 len += sg[i].length;
491
492 desc = vio_dring_cur(dr);
493
494 err = ldc_map_sg(port->vio.lp, sg, nsg,
495 desc->cookies, port->ring_cookies,
496 map_perm);
497 if (err < 0) {
498 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
499 return err;
500 }
501
502 rqe = &port->rq_arr[dr->prod];
503 rqe->req = req;
504
505 desc->hdr.ack = VIO_ACK_ENABLE;
506 desc->req_id = port->req_id;
507 desc->operation = op;
508 if (port->vdisk_type == VD_DISK_TYPE_DISK) {
509 desc->slice = 0xff;
510 } else {
511 desc->slice = 0;
512 }
513 desc->status = ~0;
514 desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
515 desc->size = len;
516 desc->ncookies = err;
517
518 /* This has to be a non-SMP write barrier because we are writing
519 * to memory which is shared with the peer LDOM.
520 */
521 wmb();
522 desc->hdr.state = VIO_DESC_READY;
523
524 err = __vdc_tx_trigger(port);
525 if (err < 0) {
526 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
527 } else {
528 port->req_id++;
529 dr->prod = vio_dring_next(dr, dr->prod);
530 }
531
532 return err;
533 }
534
535 static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx,
536 const struct blk_mq_queue_data *bd)
537 {
538 struct vdc_port *port = hctx->queue->queuedata;
539 struct vio_dring_state *dr;
540 unsigned long flags;
541
542 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
543
544 blk_mq_start_request(bd->rq);
545
546 spin_lock_irqsave(&port->vio.lock, flags);
547
548 /*
549 * Doing drain, just end the request in error
550 */
551 if (unlikely(port->drain)) {
552 spin_unlock_irqrestore(&port->vio.lock, flags);
553 return BLK_STS_IOERR;
554 }
555
556 if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
557 spin_unlock_irqrestore(&port->vio.lock, flags);
558 blk_mq_stop_hw_queue(hctx);
559 return BLK_STS_DEV_RESOURCE;
560 }
561
562 if (__send_request(bd->rq) < 0) {
563 spin_unlock_irqrestore(&port->vio.lock, flags);
564 return BLK_STS_IOERR;
565 }
566
567 spin_unlock_irqrestore(&port->vio.lock, flags);
568 return BLK_STS_OK;
569 }
570
571 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
572 {
573 struct vio_dring_state *dr;
574 struct vio_completion comp;
575 struct vio_disk_desc *desc;
576 unsigned int map_perm;
577 unsigned long flags;
578 int op_len, err;
579 void *req_buf;
580
581 if (!(((u64)1 << (u64)op) & port->operations))
582 return -EOPNOTSUPP;
583
584 switch (op) {
585 case VD_OP_BREAD:
586 case VD_OP_BWRITE:
587 default:
588 return -EINVAL;
589
590 case VD_OP_FLUSH:
591 op_len = 0;
592 map_perm = 0;
593 break;
594
595 case VD_OP_GET_WCE:
596 op_len = sizeof(u32);
597 map_perm = LDC_MAP_W;
598 break;
599
600 case VD_OP_SET_WCE:
601 op_len = sizeof(u32);
602 map_perm = LDC_MAP_R;
603 break;
604
605 case VD_OP_GET_VTOC:
606 op_len = sizeof(struct vio_disk_vtoc);
607 map_perm = LDC_MAP_W;
608 break;
609
610 case VD_OP_SET_VTOC:
611 op_len = sizeof(struct vio_disk_vtoc);
612 map_perm = LDC_MAP_R;
613 break;
614
615 case VD_OP_GET_DISKGEOM:
616 op_len = sizeof(struct vio_disk_geom);
617 map_perm = LDC_MAP_W;
618 break;
619
620 case VD_OP_SET_DISKGEOM:
621 op_len = sizeof(struct vio_disk_geom);
622 map_perm = LDC_MAP_R;
623 break;
624
625 case VD_OP_SCSICMD:
626 op_len = 16;
627 map_perm = LDC_MAP_RW;
628 break;
629
630 case VD_OP_GET_DEVID:
631 op_len = sizeof(struct vio_disk_devid);
632 map_perm = LDC_MAP_W;
633 break;
634
635 case VD_OP_GET_EFI:
636 case VD_OP_SET_EFI:
637 return -EOPNOTSUPP;
638 }
639
640 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
641
642 op_len = (op_len + 7) & ~7;
643 req_buf = kzalloc(op_len, GFP_KERNEL);
644 if (!req_buf)
645 return -ENOMEM;
646
647 if (len > op_len)
648 len = op_len;
649
650 if (map_perm & LDC_MAP_R)
651 memcpy(req_buf, buf, len);
652
653 spin_lock_irqsave(&port->vio.lock, flags);
654
655 dr = &port->vio.drings[VIO_DRIVER_TX_RING];
656
657 /* XXX If we want to use this code generically we have to
658 * XXX handle TX ring exhaustion etc.
659 */
660 desc = vio_dring_cur(dr);
661
662 err = ldc_map_single(port->vio.lp, req_buf, op_len,
663 desc->cookies, port->ring_cookies,
664 map_perm);
665 if (err < 0) {
666 spin_unlock_irqrestore(&port->vio.lock, flags);
667 kfree(req_buf);
668 return err;
669 }
670
671 init_completion(&comp.com);
672 comp.waiting_for = WAITING_FOR_GEN_CMD;
673 port->vio.cmp = &comp;
674
675 desc->hdr.ack = VIO_ACK_ENABLE;
676 desc->req_id = port->req_id;
677 desc->operation = op;
678 desc->slice = 0;
679 desc->status = ~0;
680 desc->offset = 0;
681 desc->size = op_len;
682 desc->ncookies = err;
683
684 /* This has to be a non-SMP write barrier because we are writing
685 * to memory which is shared with the peer LDOM.
686 */
687 wmb();
688 desc->hdr.state = VIO_DESC_READY;
689
690 err = __vdc_tx_trigger(port);
691 if (err >= 0) {
692 port->req_id++;
693 dr->prod = vio_dring_next(dr, dr->prod);
694 spin_unlock_irqrestore(&port->vio.lock, flags);
695
696 wait_for_completion(&comp.com);
697 err = comp.err;
698 } else {
699 port->vio.cmp = NULL;
700 spin_unlock_irqrestore(&port->vio.lock, flags);
701 }
702
703 if (map_perm & LDC_MAP_W)
704 memcpy(buf, req_buf, len);
705
706 kfree(req_buf);
707
708 return err;
709 }
710
711 static int vdc_alloc_tx_ring(struct vdc_port *port)
712 {
713 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
714 unsigned long len, entry_size;
715 int ncookies;
716 void *dring;
717
718 entry_size = sizeof(struct vio_disk_desc) +
719 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
720 len = (VDC_TX_RING_SIZE * entry_size);
721
722 ncookies = VIO_MAX_RING_COOKIES;
723 dring = ldc_alloc_exp_dring(port->vio.lp, len,
724 dr->cookies, &ncookies,
725 (LDC_MAP_SHADOW |
726 LDC_MAP_DIRECT |
727 LDC_MAP_RW));
728 if (IS_ERR(dring))
729 return PTR_ERR(dring);
730
731 dr->base = dring;
732 dr->entry_size = entry_size;
733 dr->num_entries = VDC_TX_RING_SIZE;
734 dr->prod = dr->cons = 0;
735 dr->pending = VDC_TX_RING_SIZE;
736 dr->ncookies = ncookies;
737
738 return 0;
739 }
740
741 static void vdc_free_tx_ring(struct vdc_port *port)
742 {
743 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
744
745 if (dr->base) {
746 ldc_free_exp_dring(port->vio.lp, dr->base,
747 (dr->entry_size * dr->num_entries),
748 dr->cookies, dr->ncookies);
749 dr->base = NULL;
750 dr->entry_size = 0;
751 dr->num_entries = 0;
752 dr->pending = 0;
753 dr->ncookies = 0;
754 }
755 }
756
757 static int vdc_port_up(struct vdc_port *port)
758 {
759 struct vio_completion comp;
760
761 init_completion(&comp.com);
762 comp.err = 0;
763 comp.waiting_for = WAITING_FOR_LINK_UP;
764 port->vio.cmp = &comp;
765
766 vio_port_up(&port->vio);
767 wait_for_completion(&comp.com);
768 return comp.err;
769 }
770
771 static void vdc_port_down(struct vdc_port *port)
772 {
773 ldc_disconnect(port->vio.lp);
774 ldc_unbind(port->vio.lp);
775 vdc_free_tx_ring(port);
776 vio_ldc_free(&port->vio);
777 }
778
779 static const struct blk_mq_ops vdc_mq_ops = {
780 .queue_rq = vdc_queue_rq,
781 };
782
783 static void cleanup_queue(struct request_queue *q)
784 {
785 struct vdc_port *port = q->queuedata;
786
787 blk_cleanup_queue(q);
788 blk_mq_free_tag_set(&port->tag_set);
789 }
790
791 static struct request_queue *init_queue(struct vdc_port *port)
792 {
793 struct request_queue *q;
794
795 q = blk_mq_init_sq_queue(&port->tag_set, &vdc_mq_ops, VDC_TX_RING_SIZE,
796 BLK_MQ_F_SHOULD_MERGE);
797 if (IS_ERR(q))
798 return q;
799
800 q->queuedata = port;
801 return q;
802 }
803
804 static int probe_disk(struct vdc_port *port)
805 {
806 struct request_queue *q;
807 struct gendisk *g;
808 int err;
809
810 err = vdc_port_up(port);
811 if (err)
812 return err;
813
814 /* Using version 1.2 means vdisk_phys_blksz should be set unless the
815 * disk is reserved by another system.
816 */
817 if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz)
818 return -ENODEV;
819
820 if (vdc_version_supported(port, 1, 1)) {
821 /* vdisk_size should be set during the handshake, if it wasn't
822 * then the underlying disk is reserved by another system
823 */
824 if (port->vdisk_size == -1)
825 return -ENODEV;
826 } else {
827 struct vio_disk_geom geom;
828
829 err = generic_request(port, VD_OP_GET_DISKGEOM,
830 &geom, sizeof(geom));
831 if (err < 0) {
832 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
833 "error %d\n", err);
834 return err;
835 }
836 port->vdisk_size = ((u64)geom.num_cyl *
837 (u64)geom.num_hd *
838 (u64)geom.num_sec);
839 }
840
841 q = init_queue(port);
842 if (IS_ERR(q)) {
843 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
844 port->vio.name);
845 return PTR_ERR(q);
846 }
847 g = alloc_disk(1 << PARTITION_SHIFT);
848 if (!g) {
849 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
850 port->vio.name);
851 cleanup_queue(q);
852 return -ENOMEM;
853 }
854
855 port->disk = g;
856
857 /* Each segment in a request is up to an aligned page in size. */
858 blk_queue_segment_boundary(q, PAGE_SIZE - 1);
859 blk_queue_max_segment_size(q, PAGE_SIZE);
860
861 blk_queue_max_segments(q, port->ring_cookies);
862 blk_queue_max_hw_sectors(q, port->max_xfer_size);
863 g->major = vdc_major;
864 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
865 strcpy(g->disk_name, port->disk_name);
866
867 g->fops = &vdc_fops;
868 g->queue = q;
869 g->private_data = port;
870
871 set_capacity(g, port->vdisk_size);
872
873 if (vdc_version_supported(port, 1, 1)) {
874 switch (port->vdisk_mtype) {
875 case VD_MEDIA_TYPE_CD:
876 pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
877 g->flags |= GENHD_FL_CD;
878 g->flags |= GENHD_FL_REMOVABLE;
879 set_disk_ro(g, 1);
880 break;
881
882 case VD_MEDIA_TYPE_DVD:
883 pr_info(PFX "Virtual DVD %s\n", port->disk_name);
884 g->flags |= GENHD_FL_CD;
885 g->flags |= GENHD_FL_REMOVABLE;
886 set_disk_ro(g, 1);
887 break;
888
889 case VD_MEDIA_TYPE_FIXED:
890 pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
891 break;
892 }
893 }
894
895 blk_queue_physical_block_size(q, port->vdisk_phys_blksz);
896
897 pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
898 g->disk_name,
899 port->vdisk_size, (port->vdisk_size >> (20 - 9)),
900 port->vio.ver.major, port->vio.ver.minor);
901
902 device_add_disk(&port->vio.vdev->dev, g, NULL);
903
904 return 0;
905 }
906
907 static struct ldc_channel_config vdc_ldc_cfg = {
908 .event = vdc_event,
909 .mtu = 64,
910 .mode = LDC_MODE_UNRELIABLE,
911 };
912
913 static struct vio_driver_ops vdc_vio_ops = {
914 .send_attr = vdc_send_attr,
915 .handle_attr = vdc_handle_attr,
916 .handshake_complete = vdc_handshake_complete,
917 };
918
919 static void print_version(void)
920 {
921 static int version_printed;
922
923 if (version_printed++ == 0)
924 printk(KERN_INFO "%s", version);
925 }
926
927 struct vdc_check_port_data {
928 int dev_no;
929 char *type;
930 };
931
932 static int vdc_device_probed(struct device *dev, void *arg)
933 {
934 struct vio_dev *vdev = to_vio_dev(dev);
935 struct vdc_check_port_data *port_data;
936
937 port_data = (struct vdc_check_port_data *)arg;
938
939 if ((vdev->dev_no == port_data->dev_no) &&
940 (!(strcmp((char *)&vdev->type, port_data->type))) &&
941 dev_get_drvdata(dev)) {
942 /* This device has already been configured
943 * by vdc_port_probe()
944 */
945 return 1;
946 } else {
947 return 0;
948 }
949 }
950
951 /* Determine whether the VIO device is part of an mpgroup
952 * by locating all the virtual-device-port nodes associated
953 * with the parent virtual-device node for the VIO device
954 * and checking whether any of these nodes are vdc-ports
955 * which have already been configured.
956 *
957 * Returns true if this device is part of an mpgroup and has
958 * already been probed.
959 */
960 static bool vdc_port_mpgroup_check(struct vio_dev *vdev)
961 {
962 struct vdc_check_port_data port_data;
963 struct device *dev;
964
965 port_data.dev_no = vdev->dev_no;
966 port_data.type = (char *)&vdev->type;
967
968 dev = device_find_child(vdev->dev.parent, &port_data,
969 vdc_device_probed);
970
971 if (dev)
972 return true;
973
974 return false;
975 }
976
977 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
978 {
979 struct mdesc_handle *hp;
980 struct vdc_port *port;
981 int err;
982 const u64 *ldc_timeout;
983
984 print_version();
985
986 hp = mdesc_grab();
987
988 err = -ENODEV;
989 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
990 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
991 vdev->dev_no);
992 goto err_out_release_mdesc;
993 }
994
995 /* Check if this device is part of an mpgroup */
996 if (vdc_port_mpgroup_check(vdev)) {
997 printk(KERN_WARNING
998 "VIO: Ignoring extra vdisk port %s",
999 dev_name(&vdev->dev));
1000 goto err_out_release_mdesc;
1001 }
1002
1003 port = kzalloc(sizeof(*port), GFP_KERNEL);
1004 err = -ENOMEM;
1005 if (!port) {
1006 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
1007 goto err_out_release_mdesc;
1008 }
1009
1010 if (vdev->dev_no >= 26)
1011 snprintf(port->disk_name, sizeof(port->disk_name),
1012 VDCBLK_NAME "%c%c",
1013 'a' + ((int)vdev->dev_no / 26) - 1,
1014 'a' + ((int)vdev->dev_no % 26));
1015 else
1016 snprintf(port->disk_name, sizeof(port->disk_name),
1017 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
1018 port->vdisk_size = -1;
1019
1020 /* Actual wall time may be double due to do_generic_file_read() doing
1021 * a readahead I/O first, and once that fails it will try to read a
1022 * single page.
1023 */
1024 ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
1025 port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
1026 INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
1027 INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
1028
1029 err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
1030 vdc_versions, ARRAY_SIZE(vdc_versions),
1031 &vdc_vio_ops, port->disk_name);
1032 if (err)
1033 goto err_out_free_port;
1034
1035 port->vdisk_block_size = VDC_DEFAULT_BLK_SIZE;
1036 port->max_xfer_size = MAX_XFER_SIZE;
1037 port->ring_cookies = MAX_RING_COOKIES;
1038
1039 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1040 if (err)
1041 goto err_out_free_port;
1042
1043 err = vdc_alloc_tx_ring(port);
1044 if (err)
1045 goto err_out_free_ldc;
1046
1047 err = probe_disk(port);
1048 if (err)
1049 goto err_out_free_tx_ring;
1050
1051 /* Note that the device driver_data is used to determine
1052 * whether the port has been probed.
1053 */
1054 dev_set_drvdata(&vdev->dev, port);
1055
1056 mdesc_release(hp);
1057
1058 return 0;
1059
1060 err_out_free_tx_ring:
1061 vdc_free_tx_ring(port);
1062
1063 err_out_free_ldc:
1064 vio_ldc_free(&port->vio);
1065
1066 err_out_free_port:
1067 kfree(port);
1068
1069 err_out_release_mdesc:
1070 mdesc_release(hp);
1071 return err;
1072 }
1073
1074 static int vdc_port_remove(struct vio_dev *vdev)
1075 {
1076 struct vdc_port *port = dev_get_drvdata(&vdev->dev);
1077
1078 if (port) {
1079 blk_mq_stop_hw_queues(port->disk->queue);
1080
1081 flush_work(&port->ldc_reset_work);
1082 cancel_delayed_work_sync(&port->ldc_reset_timer_work);
1083 del_timer_sync(&port->vio.timer);
1084
1085 del_gendisk(port->disk);
1086 cleanup_queue(port->disk->queue);
1087 put_disk(port->disk);
1088 port->disk = NULL;
1089
1090 vdc_free_tx_ring(port);
1091 vio_ldc_free(&port->vio);
1092
1093 dev_set_drvdata(&vdev->dev, NULL);
1094
1095 kfree(port);
1096 }
1097 return 0;
1098 }
1099
1100 static void vdc_requeue_inflight(struct vdc_port *port)
1101 {
1102 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1103 u32 idx;
1104
1105 for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) {
1106 struct vio_disk_desc *desc = vio_dring_entry(dr, idx);
1107 struct vdc_req_entry *rqe = &port->rq_arr[idx];
1108 struct request *req;
1109
1110 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
1111 desc->hdr.state = VIO_DESC_FREE;
1112 dr->cons = vio_dring_next(dr, idx);
1113
1114 req = rqe->req;
1115 if (req == NULL) {
1116 vdc_end_special(port, desc);
1117 continue;
1118 }
1119
1120 rqe->req = NULL;
1121 blk_mq_requeue_request(req, false);
1122 }
1123 }
1124
1125 static void vdc_queue_drain(struct vdc_port *port)
1126 {
1127 struct request_queue *q = port->disk->queue;
1128
1129 /*
1130 * Mark the queue as draining, then freeze/quiesce to ensure
1131 * that all existing requests are seen in ->queue_rq() and killed
1132 */
1133 port->drain = 1;
1134 spin_unlock_irq(&port->vio.lock);
1135
1136 blk_mq_freeze_queue(q);
1137 blk_mq_quiesce_queue(q);
1138
1139 spin_lock_irq(&port->vio.lock);
1140 port->drain = 0;
1141 blk_mq_unquiesce_queue(q);
1142 blk_mq_unfreeze_queue(q);
1143 }
1144
1145 static void vdc_ldc_reset_timer_work(struct work_struct *work)
1146 {
1147 struct vdc_port *port;
1148 struct vio_driver_state *vio;
1149
1150 port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
1151 vio = &port->vio;
1152
1153 spin_lock_irq(&vio->lock);
1154 if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
1155 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
1156 port->disk_name, port->ldc_timeout);
1157 vdc_queue_drain(port);
1158 vdc_blk_queue_start(port);
1159 }
1160 spin_unlock_irq(&vio->lock);
1161 }
1162
1163 static void vdc_ldc_reset_work(struct work_struct *work)
1164 {
1165 struct vdc_port *port;
1166 struct vio_driver_state *vio;
1167 unsigned long flags;
1168
1169 port = container_of(work, struct vdc_port, ldc_reset_work);
1170 vio = &port->vio;
1171
1172 spin_lock_irqsave(&vio->lock, flags);
1173 vdc_ldc_reset(port);
1174 spin_unlock_irqrestore(&vio->lock, flags);
1175 }
1176
1177 static void vdc_ldc_reset(struct vdc_port *port)
1178 {
1179 int err;
1180
1181 assert_spin_locked(&port->vio.lock);
1182
1183 pr_warn(PFX "%s ldc link reset\n", port->disk_name);
1184 blk_mq_stop_hw_queues(port->disk->queue);
1185 vdc_requeue_inflight(port);
1186 vdc_port_down(port);
1187
1188 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1189 if (err) {
1190 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err);
1191 return;
1192 }
1193
1194 err = vdc_alloc_tx_ring(port);
1195 if (err) {
1196 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err);
1197 goto err_free_ldc;
1198 }
1199
1200 if (port->ldc_timeout)
1201 mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
1202 round_jiffies(jiffies + HZ * port->ldc_timeout));
1203 mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
1204 return;
1205
1206 err_free_ldc:
1207 vio_ldc_free(&port->vio);
1208 }
1209
1210 static const struct vio_device_id vdc_port_match[] = {
1211 {
1212 .type = "vdc-port",
1213 },
1214 {},
1215 };
1216 MODULE_DEVICE_TABLE(vio, vdc_port_match);
1217
1218 static struct vio_driver vdc_port_driver = {
1219 .id_table = vdc_port_match,
1220 .probe = vdc_port_probe,
1221 .remove = vdc_port_remove,
1222 .name = "vdc_port",
1223 };
1224
1225 static int __init vdc_init(void)
1226 {
1227 int err;
1228
1229 sunvdc_wq = alloc_workqueue("sunvdc", 0, 0);
1230 if (!sunvdc_wq)
1231 return -ENOMEM;
1232
1233 err = register_blkdev(0, VDCBLK_NAME);
1234 if (err < 0)
1235 goto out_free_wq;
1236
1237 vdc_major = err;
1238
1239 err = vio_register_driver(&vdc_port_driver);
1240 if (err)
1241 goto out_unregister_blkdev;
1242
1243 return 0;
1244
1245 out_unregister_blkdev:
1246 unregister_blkdev(vdc_major, VDCBLK_NAME);
1247 vdc_major = 0;
1248
1249 out_free_wq:
1250 destroy_workqueue(sunvdc_wq);
1251 return err;
1252 }
1253
1254 static void __exit vdc_exit(void)
1255 {
1256 vio_unregister_driver(&vdc_port_driver);
1257 unregister_blkdev(vdc_major, VDCBLK_NAME);
1258 destroy_workqueue(sunvdc_wq);
1259 }
1260
1261 module_init(vdc_init);
1262 module_exit(vdc_exit);
Linux with added FPC-III support