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
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 #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
50 static struct workqueue_struct *sunvdc_wq;
51
52 struct vdc_req_entry {
53 struct request *req;
54 };
55
56 struct 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
91 static void vdc_ldc_reset(struct vdc_port *port);
92 static void vdc_ldc_reset_work(struct work_struct *work);
93 static void vdc_ldc_reset_timer_work(struct work_struct *work);
94
to_vdc_port(struct vio_driver_state * vio)95 static 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 */
101 static struct vio_version vdc_versions[] = {
102 { .major = 1, .minor = 2 },
103 { .major = 1, .minor = 1 },
104 { .major = 1, .minor = 0 },
105 };
106
vdc_version_supported(struct vdc_port * port,u16 major,u16 minor)107 static 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"
114 static int vdc_major;
115 #define PARTITION_SHIFT 3
116
vdc_tx_dring_avail(struct vio_dring_state * dr)117 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
118 {
119 return vio_dring_avail(dr, VDC_TX_RING_SIZE);
120 }
121
vdc_getgeo(struct block_device * bdev,struct hd_geometry * geo)122 static 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 */
vdc_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned command,unsigned long argument)142 static 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, 1, 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
172 static 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
vdc_blk_queue_start(struct vdc_port * port)179 static 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(port->disk->queue, true);
189 }
190
vdc_finish(struct vio_driver_state * vio,int err,int waiting_for)191 static 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
vdc_handshake_complete(struct vio_driver_state * vio)202 static void vdc_handshake_complete(struct vio_driver_state *vio)
203 {
204 struct vdc_port *port = to_vdc_port(vio);
205
206 cancel_delayed_work(&port->ldc_reset_timer_work);
207 vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
208 vdc_blk_queue_start(port);
209 }
210
vdc_handle_unknown(struct vdc_port * port,void * arg)211 static 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
vdc_send_attr(struct vio_driver_state * vio)224 static 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
vdc_handle_attr(struct vio_driver_state * vio,void * arg)246 static 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, 1, 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, 1, 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
vdc_end_special(struct vdc_port * port,struct vio_disk_desc * desc)300 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
301 {
302 int err = desc->status;
303
304 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
305 }
306
vdc_end_one(struct vdc_port * port,struct vio_dring_state * dr,unsigned int index)307 static 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(req, desc->status ? BLK_STS_IOERR : 0);
330
331 vdc_blk_queue_start(port);
332 }
333
vdc_ack(struct vdc_port * port,void * msgbuf)334 static 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, pkt->start_idx);
345
346 return 0;
347 }
348
vdc_nack(struct vdc_port * port,void * msgbuf)349 static int vdc_nack(struct vdc_port *port, void *msgbuf)
350 {
351 /* XXX Implement me XXX */
352 return 0;
353 }
354
vdc_event(void * arg,int event)355 static 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(sunvdc_wq, &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);
407 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
408 err = vdc_nack(port, &msgbuf);
409 else
410 err = vdc_handle_unknown(port, &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, &msgbuf);
415 }
416 if (err < 0)
417 break;
418 }
419 if (err < 0)
420 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
421 out:
422 spin_unlock_irqrestore(&vio->lock, flags);
423 }
424
__vdc_tx_trigger(struct vdc_port * port)425 static 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
__send_request(struct request * req)462 static 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(req->q, req, 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(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
vdc_queue_rq(struct blk_mq_hw_ctx * hctx,const struct blk_mq_queue_data * bd)537 static 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(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(&port->vio.lock, flags);
555 return BLK_STS_IOERR;
556 }
557
558 if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
559 spin_unlock_irqrestore(&port->vio.lock, flags);
560 blk_mq_stop_hw_queue(hctx);
561 return BLK_STS_DEV_RESOURCE;
562 }
563
564 if (__send_request(bd->rq) < 0) {
565 spin_unlock_irqrestore(&port->vio.lock, flags);
566 return BLK_STS_IOERR;
567 }
568
569 spin_unlock_irqrestore(&port->vio.lock, flags);
570 return BLK_STS_OK;
571 }
572
generic_request(struct vdc_port * port,u8 op,void * buf,int len)573 static 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(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(&port->vio.lock, flags);
669 kfree(req_buf);
670 return err;
671 }
672
673 init_completion(&comp.com);
674 comp.waiting_for = WAITING_FOR_GEN_CMD;
675 port->vio.cmp = ∁
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(&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(&port->vio.lock, flags);
703 }
704
705 if (map_perm & LDC_MAP_W)
706 memcpy(buf, req_buf, len);
707
708 kfree(req_buf);
709
710 return err;
711 }
712
vdc_alloc_tx_ring(struct vdc_port * port)713 static 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(dring))
731 return PTR_ERR(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
vdc_free_tx_ring(struct vdc_port * port)743 static 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
vdc_port_up(struct vdc_port * port)759 static int vdc_port_up(struct vdc_port *port)
760 {
761 struct vio_completion comp;
762
763 init_completion(&comp.com);
764 comp.err = 0;
765 comp.waiting_for = WAITING_FOR_LINK_UP;
766 port->vio.cmp = ∁
767
768 vio_port_up(&port->vio);
769 wait_for_completion(&comp.com);
770 return comp.err;
771 }
772
vdc_port_down(struct vdc_port * port)773 static 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
781 static const struct blk_mq_ops vdc_mq_ops = {
782 .queue_rq = vdc_queue_rq,
783 };
784
probe_disk(struct vdc_port * port)785 static int probe_disk(struct vdc_port *port)
786 {
787 struct queue_limits lim = {
788 .physical_block_size = port->vdisk_phys_blksz,
789 .max_hw_sectors = port->max_xfer_size,
790 /* Each segment in a request is up to an aligned page in size. */
791 .seg_boundary_mask = PAGE_SIZE - 1,
792 .max_segment_size = PAGE_SIZE,
793 .max_segments = port->ring_cookies,
794 .features = BLK_FEAT_ROTATIONAL,
795 };
796 struct request_queue *q;
797 struct gendisk *g;
798 int err;
799
800 err = vdc_port_up(port);
801 if (err)
802 return err;
803
804 /* Using version 1.2 means vdisk_phys_blksz should be set unless the
805 * disk is reserved by another system.
806 */
807 if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz)
808 return -ENODEV;
809
810 if (vdc_version_supported(port, 1, 1)) {
811 /* vdisk_size should be set during the handshake, if it wasn't
812 * then the underlying disk is reserved by another system
813 */
814 if (port->vdisk_size == -1)
815 return -ENODEV;
816 } else {
817 struct vio_disk_geom geom;
818
819 err = generic_request(port, VD_OP_GET_DISKGEOM,
820 &geom, sizeof(geom));
821 if (err < 0) {
822 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
823 "error %d\n", err);
824 return err;
825 }
826 port->vdisk_size = ((u64)geom.num_cyl *
827 (u64)geom.num_hd *
828 (u64)geom.num_sec);
829 }
830
831 err = blk_mq_alloc_sq_tag_set(&port->tag_set, &vdc_mq_ops,
832 VDC_TX_RING_SIZE, BLK_MQ_F_SHOULD_MERGE);
833 if (err)
834 return err;
835
836 g = blk_mq_alloc_disk(&port->tag_set, &lim, port);
837 if (IS_ERR(g)) {
838 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
839 port->vio.name);
840 err = PTR_ERR(g);
841 goto out_free_tag;
842 }
843
844 port->disk = g;
845 q = g->queue;
846
847 g->major = vdc_major;
848 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
849 g->minors = 1 << PARTITION_SHIFT;
850 strcpy(g->disk_name, port->disk_name);
851
852 g->fops = &vdc_fops;
853 g->queue = q;
854 g->private_data = port;
855
856 set_capacity(g, port->vdisk_size);
857
858 if (vdc_version_supported(port, 1, 1)) {
859 switch (port->vdisk_mtype) {
860 case VD_MEDIA_TYPE_CD:
861 pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
862 g->flags |= GENHD_FL_REMOVABLE;
863 set_disk_ro(g, 1);
864 break;
865
866 case VD_MEDIA_TYPE_DVD:
867 pr_info(PFX "Virtual DVD %s\n", port->disk_name);
868 g->flags |= GENHD_FL_REMOVABLE;
869 set_disk_ro(g, 1);
870 break;
871
872 case VD_MEDIA_TYPE_FIXED:
873 pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
874 break;
875 }
876 }
877
878 pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
879 g->disk_name,
880 port->vdisk_size, (port->vdisk_size >> (20 - 9)),
881 port->vio.ver.major, port->vio.ver.minor);
882
883 err = device_add_disk(&port->vio.vdev->dev, g, NULL);
884 if (err)
885 goto out_cleanup_disk;
886
887 return 0;
888
889 out_cleanup_disk:
890 put_disk(g);
891 out_free_tag:
892 blk_mq_free_tag_set(&port->tag_set);
893 return err;
894 }
895
896 static struct ldc_channel_config vdc_ldc_cfg = {
897 .event = vdc_event,
898 .mtu = 64,
899 .mode = LDC_MODE_UNRELIABLE,
900 };
901
902 static struct vio_driver_ops vdc_vio_ops = {
903 .send_attr = vdc_send_attr,
904 .handle_attr = vdc_handle_attr,
905 .handshake_complete = vdc_handshake_complete,
906 };
907
print_version(void)908 static void print_version(void)
909 {
910 static int version_printed;
911
912 if (version_printed++ == 0)
913 printk(KERN_INFO "%s", version);
914 }
915
916 struct vdc_check_port_data {
917 int dev_no;
918 char *type;
919 };
920
vdc_device_probed(struct device * dev,void * arg)921 static int vdc_device_probed(struct device *dev, void *arg)
922 {
923 struct vio_dev *vdev = to_vio_dev(dev);
924 struct vdc_check_port_data *port_data;
925
926 port_data = (struct vdc_check_port_data *)arg;
927
928 if ((vdev->dev_no == port_data->dev_no) &&
929 (!(strcmp((char *)&vdev->type, port_data->type))) &&
930 dev_get_drvdata(dev)) {
931 /* This device has already been configured
932 * by vdc_port_probe()
933 */
934 return 1;
935 } else {
936 return 0;
937 }
938 }
939
940 /* Determine whether the VIO device is part of an mpgroup
941 * by locating all the virtual-device-port nodes associated
942 * with the parent virtual-device node for the VIO device
943 * and checking whether any of these nodes are vdc-ports
944 * which have already been configured.
945 *
946 * Returns true if this device is part of an mpgroup and has
947 * already been probed.
948 */
vdc_port_mpgroup_check(struct vio_dev * vdev)949 static bool vdc_port_mpgroup_check(struct vio_dev *vdev)
950 {
951 struct vdc_check_port_data port_data;
952 struct device *dev;
953
954 port_data.dev_no = vdev->dev_no;
955 port_data.type = (char *)&vdev->type;
956
957 dev = device_find_child(vdev->dev.parent, &port_data,
958 vdc_device_probed);
959
960 if (dev)
961 return true;
962
963 return false;
964 }
965
vdc_port_probe(struct vio_dev * vdev,const struct vio_device_id * id)966 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
967 {
968 struct mdesc_handle *hp;
969 struct vdc_port *port;
970 int err;
971 const u64 *ldc_timeout;
972
973 print_version();
974
975 hp = mdesc_grab();
976 if (!hp)
977 return -ENODEV;
978
979 err = -ENODEV;
980 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
981 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
982 vdev->dev_no);
983 goto err_out_release_mdesc;
984 }
985
986 /* Check if this device is part of an mpgroup */
987 if (vdc_port_mpgroup_check(vdev)) {
988 printk(KERN_WARNING
989 "VIO: Ignoring extra vdisk port %s",
990 dev_name(&vdev->dev));
991 goto err_out_release_mdesc;
992 }
993
994 port = kzalloc(sizeof(*port), GFP_KERNEL);
995 if (!port) {
996 err = -ENOMEM;
997 goto err_out_release_mdesc;
998 }
999
1000 if (vdev->dev_no >= 26)
1001 snprintf(port->disk_name, sizeof(port->disk_name),
1002 VDCBLK_NAME "%c%c",
1003 'a' + ((int)vdev->dev_no / 26) - 1,
1004 'a' + ((int)vdev->dev_no % 26));
1005 else
1006 snprintf(port->disk_name, sizeof(port->disk_name),
1007 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
1008 port->vdisk_size = -1;
1009
1010 /* Actual wall time may be double due to do_generic_file_read() doing
1011 * a readahead I/O first, and once that fails it will try to read a
1012 * single page.
1013 */
1014 ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
1015 port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
1016 INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
1017 INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
1018
1019 err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
1020 vdc_versions, ARRAY_SIZE(vdc_versions),
1021 &vdc_vio_ops, port->disk_name);
1022 if (err)
1023 goto err_out_free_port;
1024
1025 port->vdisk_block_size = VDC_DEFAULT_BLK_SIZE;
1026 port->max_xfer_size = MAX_XFER_SIZE;
1027 port->ring_cookies = MAX_RING_COOKIES;
1028
1029 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1030 if (err)
1031 goto err_out_free_port;
1032
1033 err = vdc_alloc_tx_ring(port);
1034 if (err)
1035 goto err_out_free_ldc;
1036
1037 err = probe_disk(port);
1038 if (err)
1039 goto err_out_free_tx_ring;
1040
1041 /* Note that the device driver_data is used to determine
1042 * whether the port has been probed.
1043 */
1044 dev_set_drvdata(&vdev->dev, port);
1045
1046 mdesc_release(hp);
1047
1048 return 0;
1049
1050 err_out_free_tx_ring:
1051 vdc_free_tx_ring(port);
1052
1053 err_out_free_ldc:
1054 vio_ldc_free(&port->vio);
1055
1056 err_out_free_port:
1057 kfree(port);
1058
1059 err_out_release_mdesc:
1060 mdesc_release(hp);
1061 return err;
1062 }
1063
vdc_port_remove(struct vio_dev * vdev)1064 static void vdc_port_remove(struct vio_dev *vdev)
1065 {
1066 struct vdc_port *port = dev_get_drvdata(&vdev->dev);
1067
1068 if (port) {
1069 blk_mq_stop_hw_queues(port->disk->queue);
1070
1071 flush_work(&port->ldc_reset_work);
1072 cancel_delayed_work_sync(&port->ldc_reset_timer_work);
1073 del_timer_sync(&port->vio.timer);
1074
1075 del_gendisk(port->disk);
1076 put_disk(port->disk);
1077 blk_mq_free_tag_set(&port->tag_set);
1078
1079 vdc_free_tx_ring(port);
1080 vio_ldc_free(&port->vio);
1081
1082 dev_set_drvdata(&vdev->dev, NULL);
1083
1084 kfree(port);
1085 }
1086 }
1087
vdc_requeue_inflight(struct vdc_port * port)1088 static void vdc_requeue_inflight(struct vdc_port *port)
1089 {
1090 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1091 u32 idx;
1092
1093 for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) {
1094 struct vio_disk_desc *desc = vio_dring_entry(dr, idx);
1095 struct vdc_req_entry *rqe = &port->rq_arr[idx];
1096 struct request *req;
1097
1098 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
1099 desc->hdr.state = VIO_DESC_FREE;
1100 dr->cons = vio_dring_next(dr, idx);
1101
1102 req = rqe->req;
1103 if (req == NULL) {
1104 vdc_end_special(port, desc);
1105 continue;
1106 }
1107
1108 rqe->req = NULL;
1109 blk_mq_requeue_request(req, false);
1110 }
1111 }
1112
vdc_queue_drain(struct vdc_port * port)1113 static void vdc_queue_drain(struct vdc_port *port)
1114 {
1115 struct request_queue *q = port->disk->queue;
1116
1117 /*
1118 * Mark the queue as draining, then freeze/quiesce to ensure
1119 * that all existing requests are seen in ->queue_rq() and killed
1120 */
1121 port->drain = 1;
1122 spin_unlock_irq(&port->vio.lock);
1123
1124 blk_mq_freeze_queue(q);
1125 blk_mq_quiesce_queue(q);
1126
1127 spin_lock_irq(&port->vio.lock);
1128 port->drain = 0;
1129 blk_mq_unquiesce_queue(q);
1130 blk_mq_unfreeze_queue(q);
1131 }
1132
vdc_ldc_reset_timer_work(struct work_struct * work)1133 static void vdc_ldc_reset_timer_work(struct work_struct *work)
1134 {
1135 struct vdc_port *port;
1136 struct vio_driver_state *vio;
1137
1138 port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
1139 vio = &port->vio;
1140
1141 spin_lock_irq(&vio->lock);
1142 if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
1143 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
1144 port->disk_name, port->ldc_timeout);
1145 vdc_queue_drain(port);
1146 vdc_blk_queue_start(port);
1147 }
1148 spin_unlock_irq(&vio->lock);
1149 }
1150
vdc_ldc_reset_work(struct work_struct * work)1151 static void vdc_ldc_reset_work(struct work_struct *work)
1152 {
1153 struct vdc_port *port;
1154 struct vio_driver_state *vio;
1155 unsigned long flags;
1156
1157 port = container_of(work, struct vdc_port, ldc_reset_work);
1158 vio = &port->vio;
1159
1160 spin_lock_irqsave(&vio->lock, flags);
1161 vdc_ldc_reset(port);
1162 spin_unlock_irqrestore(&vio->lock, flags);
1163 }
1164
vdc_ldc_reset(struct vdc_port * port)1165 static void vdc_ldc_reset(struct vdc_port *port)
1166 {
1167 int err;
1168
1169 assert_spin_locked(&port->vio.lock);
1170
1171 pr_warn(PFX "%s ldc link reset\n", port->disk_name);
1172 blk_mq_stop_hw_queues(port->disk->queue);
1173 vdc_requeue_inflight(port);
1174 vdc_port_down(port);
1175
1176 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1177 if (err) {
1178 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err);
1179 return;
1180 }
1181
1182 err = vdc_alloc_tx_ring(port);
1183 if (err) {
1184 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err);
1185 goto err_free_ldc;
1186 }
1187
1188 if (port->ldc_timeout)
1189 mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
1190 round_jiffies(jiffies + HZ * port->ldc_timeout));
1191 mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
1192 return;
1193
1194 err_free_ldc:
1195 vio_ldc_free(&port->vio);
1196 }
1197
1198 static const struct vio_device_id vdc_port_match[] = {
1199 {
1200 .type = "vdc-port",
1201 },
1202 {},
1203 };
1204 MODULE_DEVICE_TABLE(vio, vdc_port_match);
1205
1206 static struct vio_driver vdc_port_driver = {
1207 .id_table = vdc_port_match,
1208 .probe = vdc_port_probe,
1209 .remove = vdc_port_remove,
1210 .name = "vdc_port",
1211 };
1212
vdc_init(void)1213 static int __init vdc_init(void)
1214 {
1215 int err;
1216
1217 sunvdc_wq = alloc_workqueue("sunvdc", 0, 0);
1218 if (!sunvdc_wq)
1219 return -ENOMEM;
1220
1221 err = register_blkdev(0, VDCBLK_NAME);
1222 if (err < 0)
1223 goto out_free_wq;
1224
1225 vdc_major = err;
1226
1227 err = vio_register_driver(&vdc_port_driver);
1228 if (err)
1229 goto out_unregister_blkdev;
1230
1231 return 0;
1232
1233 out_unregister_blkdev:
1234 unregister_blkdev(vdc_major, VDCBLK_NAME);
1235 vdc_major = 0;
1236
1237 out_free_wq:
1238 destroy_workqueue(sunvdc_wq);
1239 return err;
1240 }
1241
vdc_exit(void)1242 static void __exit vdc_exit(void)
1243 {
1244 vio_unregister_driver(&vdc_port_driver);
1245 unregister_blkdev(vdc_major, VDCBLK_NAME);
1246 destroy_workqueue(sunvdc_wq);
1247 }
1248
1249 module_init(vdc_init);
1250 module_exit(vdc_exit);
1251