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

source code of linux/drivers/block/sunvdc.c