Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[linux-2.6] / drivers / block / sunvdc.c
1 /* sunvdc.c: Sun LDOM Virtual Disk Client.
2  *
3  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
4  */
5
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/blkdev.h>
10 #include <linux/hdreg.h>
11 #include <linux/genhd.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 #include <linux/completion.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/list.h>
18 #include <linux/scatterlist.h>
19
20 #include <asm/vio.h>
21 #include <asm/ldc.h>
22
23 #define DRV_MODULE_NAME         "sunvdc"
24 #define PFX DRV_MODULE_NAME     ": "
25 #define DRV_MODULE_VERSION      "1.0"
26 #define DRV_MODULE_RELDATE      "June 25, 2007"
27
28 static char version[] __devinitdata =
29         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
30 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
31 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
32 MODULE_LICENSE("GPL");
33 MODULE_VERSION(DRV_MODULE_VERSION);
34
35 #define VDC_TX_RING_SIZE        256
36
37 #define WAITING_FOR_LINK_UP     0x01
38 #define WAITING_FOR_TX_SPACE    0x02
39 #define WAITING_FOR_GEN_CMD     0x04
40 #define WAITING_FOR_ANY         -1
41
42 struct vdc_req_entry {
43         struct request          *req;
44 };
45
46 struct vdc_port {
47         struct vio_driver_state vio;
48
49         struct gendisk          *disk;
50
51         struct vdc_completion   *cmp;
52
53         u64                     req_id;
54         u64                     seq;
55         struct vdc_req_entry    rq_arr[VDC_TX_RING_SIZE];
56
57         unsigned long           ring_cookies;
58
59         u64                     max_xfer_size;
60         u32                     vdisk_block_size;
61
62         /* The server fills these in for us in the disk attribute
63          * ACK packet.
64          */
65         u64                     operations;
66         u32                     vdisk_size;
67         u8                      vdisk_type;
68
69         char                    disk_name[32];
70
71         struct vio_disk_geom    geom;
72         struct vio_disk_vtoc    label;
73 };
74
75 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
76 {
77         return container_of(vio, struct vdc_port, vio);
78 }
79
80 /* Ordered from largest major to lowest */
81 static struct vio_version vdc_versions[] = {
82         { .major = 1, .minor = 0 },
83 };
84
85 #define VDCBLK_NAME     "vdisk"
86 static int vdc_major;
87 #define PARTITION_SHIFT 3
88
89 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
90 {
91         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
92 }
93
94 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
95 {
96         struct gendisk *disk = bdev->bd_disk;
97         struct vdc_port *port = disk->private_data;
98
99         geo->heads = (u8) port->geom.num_hd;
100         geo->sectors = (u8) port->geom.num_sec;
101         geo->cylinders = port->geom.num_cyl;
102
103         return 0;
104 }
105
106 static struct block_device_operations vdc_fops = {
107         .owner          = THIS_MODULE,
108         .getgeo         = vdc_getgeo,
109 };
110
111 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
112 {
113         if (vio->cmp &&
114             (waiting_for == -1 ||
115              vio->cmp->waiting_for == waiting_for)) {
116                 vio->cmp->err = err;
117                 complete(&vio->cmp->com);
118                 vio->cmp = NULL;
119         }
120 }
121
122 static void vdc_handshake_complete(struct vio_driver_state *vio)
123 {
124         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
125 }
126
127 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
128 {
129         struct vio_msg_tag *pkt = arg;
130
131         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
132                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
133         printk(KERN_ERR PFX "Resetting connection.\n");
134
135         ldc_disconnect(port->vio.lp);
136
137         return -ECONNRESET;
138 }
139
140 static int vdc_send_attr(struct vio_driver_state *vio)
141 {
142         struct vdc_port *port = to_vdc_port(vio);
143         struct vio_disk_attr_info pkt;
144
145         memset(&pkt, 0, sizeof(pkt));
146
147         pkt.tag.type = VIO_TYPE_CTRL;
148         pkt.tag.stype = VIO_SUBTYPE_INFO;
149         pkt.tag.stype_env = VIO_ATTR_INFO;
150         pkt.tag.sid = vio_send_sid(vio);
151
152         pkt.xfer_mode = VIO_DRING_MODE;
153         pkt.vdisk_block_size = port->vdisk_block_size;
154         pkt.max_xfer_size = port->max_xfer_size;
155
156         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
157                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
158
159         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
160 }
161
162 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
163 {
164         struct vdc_port *port = to_vdc_port(vio);
165         struct vio_disk_attr_info *pkt = arg;
166
167         viodbg(HS, "GOT ATTR stype[0x%x] ops[%lx] disk_size[%lu] disk_type[%x] "
168                "xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
169                pkt->tag.stype, pkt->operations,
170                pkt->vdisk_size, pkt->vdisk_type,
171                pkt->xfer_mode, pkt->vdisk_block_size,
172                pkt->max_xfer_size);
173
174         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
175                 switch (pkt->vdisk_type) {
176                 case VD_DISK_TYPE_DISK:
177                 case VD_DISK_TYPE_SLICE:
178                         break;
179
180                 default:
181                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
182                                vio->name, pkt->vdisk_type);
183                         return -ECONNRESET;
184                 }
185
186                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
187                         printk(KERN_ERR PFX "%s: BLOCK size increased "
188                                "%u --> %u\n",
189                                vio->name,
190                                port->vdisk_block_size, pkt->vdisk_block_size);
191                         return -ECONNRESET;
192                 }
193
194                 port->operations = pkt->operations;
195                 port->vdisk_size = pkt->vdisk_size;
196                 port->vdisk_type = pkt->vdisk_type;
197                 if (pkt->max_xfer_size < port->max_xfer_size)
198                         port->max_xfer_size = pkt->max_xfer_size;
199                 port->vdisk_block_size = pkt->vdisk_block_size;
200                 return 0;
201         } else {
202                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
203
204                 return -ECONNRESET;
205         }
206 }
207
208 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
209 {
210         int err = desc->status;
211
212         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
213 }
214
215 static void vdc_end_request(struct request *req, int error, int num_sectors)
216 {
217         __blk_end_request(req, error, num_sectors << 9);
218 }
219
220 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
221                         unsigned int index)
222 {
223         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
224         struct vdc_req_entry *rqe = &port->rq_arr[index];
225         struct request *req;
226
227         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
228                 return;
229
230         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
231         desc->hdr.state = VIO_DESC_FREE;
232         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
233
234         req = rqe->req;
235         if (req == NULL) {
236                 vdc_end_special(port, desc);
237                 return;
238         }
239
240         rqe->req = NULL;
241
242         vdc_end_request(req, (desc->status ? -EIO : 0), desc->size >> 9);
243
244         if (blk_queue_stopped(port->disk->queue))
245                 blk_start_queue(port->disk->queue);
246 }
247
248 static int vdc_ack(struct vdc_port *port, void *msgbuf)
249 {
250         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
251         struct vio_dring_data *pkt = msgbuf;
252
253         if (unlikely(pkt->dring_ident != dr->ident ||
254                      pkt->start_idx != pkt->end_idx ||
255                      pkt->start_idx >= VDC_TX_RING_SIZE))
256                 return 0;
257
258         vdc_end_one(port, dr, pkt->start_idx);
259
260         return 0;
261 }
262
263 static int vdc_nack(struct vdc_port *port, void *msgbuf)
264 {
265         /* XXX Implement me XXX */
266         return 0;
267 }
268
269 static void vdc_event(void *arg, int event)
270 {
271         struct vdc_port *port = arg;
272         struct vio_driver_state *vio = &port->vio;
273         unsigned long flags;
274         int err;
275
276         spin_lock_irqsave(&vio->lock, flags);
277
278         if (unlikely(event == LDC_EVENT_RESET ||
279                      event == LDC_EVENT_UP)) {
280                 vio_link_state_change(vio, event);
281                 spin_unlock_irqrestore(&vio->lock, flags);
282                 return;
283         }
284
285         if (unlikely(event != LDC_EVENT_DATA_READY)) {
286                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
287                 spin_unlock_irqrestore(&vio->lock, flags);
288                 return;
289         }
290
291         err = 0;
292         while (1) {
293                 union {
294                         struct vio_msg_tag tag;
295                         u64 raw[8];
296                 } msgbuf;
297
298                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
299                 if (unlikely(err < 0)) {
300                         if (err == -ECONNRESET)
301                                 vio_conn_reset(vio);
302                         break;
303                 }
304                 if (err == 0)
305                         break;
306                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
307                        msgbuf.tag.type,
308                        msgbuf.tag.stype,
309                        msgbuf.tag.stype_env,
310                        msgbuf.tag.sid);
311                 err = vio_validate_sid(vio, &msgbuf.tag);
312                 if (err < 0)
313                         break;
314
315                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
316                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
317                                 err = vdc_ack(port, &msgbuf);
318                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
319                                 err = vdc_nack(port, &msgbuf);
320                         else
321                                 err = vdc_handle_unknown(port, &msgbuf);
322                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
323                         err = vio_control_pkt_engine(vio, &msgbuf);
324                 } else {
325                         err = vdc_handle_unknown(port, &msgbuf);
326                 }
327                 if (err < 0)
328                         break;
329         }
330         if (err < 0)
331                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
332         spin_unlock_irqrestore(&vio->lock, flags);
333 }
334
335 static int __vdc_tx_trigger(struct vdc_port *port)
336 {
337         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
338         struct vio_dring_data hdr = {
339                 .tag = {
340                         .type           = VIO_TYPE_DATA,
341                         .stype          = VIO_SUBTYPE_INFO,
342                         .stype_env      = VIO_DRING_DATA,
343                         .sid            = vio_send_sid(&port->vio),
344                 },
345                 .dring_ident            = dr->ident,
346                 .start_idx              = dr->prod,
347                 .end_idx                = dr->prod,
348         };
349         int err, delay;
350
351         hdr.seq = dr->snd_nxt;
352         delay = 1;
353         do {
354                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
355                 if (err > 0) {
356                         dr->snd_nxt++;
357                         break;
358                 }
359                 udelay(delay);
360                 if ((delay <<= 1) > 128)
361                         delay = 128;
362         } while (err == -EAGAIN);
363
364         return err;
365 }
366
367 static int __send_request(struct request *req)
368 {
369         struct vdc_port *port = req->rq_disk->private_data;
370         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
371         struct scatterlist sg[port->ring_cookies];
372         struct vdc_req_entry *rqe;
373         struct vio_disk_desc *desc;
374         unsigned int map_perm;
375         int nsg, err, i;
376         u64 len;
377         u8 op;
378
379         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
380
381         if (rq_data_dir(req) == READ) {
382                 map_perm |= LDC_MAP_W;
383                 op = VD_OP_BREAD;
384         } else {
385                 map_perm |= LDC_MAP_R;
386                 op = VD_OP_BWRITE;
387         }
388
389         sg_init_table(sg, port->ring_cookies);
390         nsg = blk_rq_map_sg(req->q, req, sg);
391
392         len = 0;
393         for (i = 0; i < nsg; i++)
394                 len += sg[i].length;
395
396         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
397                 blk_stop_queue(port->disk->queue);
398                 err = -ENOMEM;
399                 goto out;
400         }
401
402         desc = vio_dring_cur(dr);
403
404         err = ldc_map_sg(port->vio.lp, sg, nsg,
405                          desc->cookies, port->ring_cookies,
406                          map_perm);
407         if (err < 0) {
408                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
409                 return err;
410         }
411
412         rqe = &port->rq_arr[dr->prod];
413         rqe->req = req;
414
415         desc->hdr.ack = VIO_ACK_ENABLE;
416         desc->req_id = port->req_id;
417         desc->operation = op;
418         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
419                 desc->slice = 0xff;
420         } else {
421                 desc->slice = 0;
422         }
423         desc->status = ~0;
424         desc->offset = (req->sector << 9) / port->vdisk_block_size;
425         desc->size = len;
426         desc->ncookies = err;
427
428         /* This has to be a non-SMP write barrier because we are writing
429          * to memory which is shared with the peer LDOM.
430          */
431         wmb();
432         desc->hdr.state = VIO_DESC_READY;
433
434         err = __vdc_tx_trigger(port);
435         if (err < 0) {
436                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
437         } else {
438                 port->req_id++;
439                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
440         }
441 out:
442
443         return err;
444 }
445
446 static void do_vdc_request(struct request_queue *q)
447 {
448         while (1) {
449                 struct request *req = elv_next_request(q);
450
451                 if (!req)
452                         break;
453
454                 blkdev_dequeue_request(req);
455                 if (__send_request(req) < 0)
456                         vdc_end_request(req, -EIO, req->hard_nr_sectors);
457         }
458 }
459
460 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
461 {
462         struct vio_dring_state *dr;
463         struct vio_completion comp;
464         struct vio_disk_desc *desc;
465         unsigned int map_perm;
466         unsigned long flags;
467         int op_len, err;
468         void *req_buf;
469
470         if (!(((u64)1 << ((u64)op - 1)) & port->operations))
471                 return -EOPNOTSUPP;
472
473         switch (op) {
474         case VD_OP_BREAD:
475         case VD_OP_BWRITE:
476         default:
477                 return -EINVAL;
478
479         case VD_OP_FLUSH:
480                 op_len = 0;
481                 map_perm = 0;
482                 break;
483
484         case VD_OP_GET_WCE:
485                 op_len = sizeof(u32);
486                 map_perm = LDC_MAP_W;
487                 break;
488
489         case VD_OP_SET_WCE:
490                 op_len = sizeof(u32);
491                 map_perm = LDC_MAP_R;
492                 break;
493
494         case VD_OP_GET_VTOC:
495                 op_len = sizeof(struct vio_disk_vtoc);
496                 map_perm = LDC_MAP_W;
497                 break;
498
499         case VD_OP_SET_VTOC:
500                 op_len = sizeof(struct vio_disk_vtoc);
501                 map_perm = LDC_MAP_R;
502                 break;
503
504         case VD_OP_GET_DISKGEOM:
505                 op_len = sizeof(struct vio_disk_geom);
506                 map_perm = LDC_MAP_W;
507                 break;
508
509         case VD_OP_SET_DISKGEOM:
510                 op_len = sizeof(struct vio_disk_geom);
511                 map_perm = LDC_MAP_R;
512                 break;
513
514         case VD_OP_SCSICMD:
515                 op_len = 16;
516                 map_perm = LDC_MAP_RW;
517                 break;
518
519         case VD_OP_GET_DEVID:
520                 op_len = sizeof(struct vio_disk_devid);
521                 map_perm = LDC_MAP_W;
522                 break;
523
524         case VD_OP_GET_EFI:
525         case VD_OP_SET_EFI:
526                 return -EOPNOTSUPP;
527                 break;
528         };
529
530         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
531
532         op_len = (op_len + 7) & ~7;
533         req_buf = kzalloc(op_len, GFP_KERNEL);
534         if (!req_buf)
535                 return -ENOMEM;
536
537         if (len > op_len)
538                 len = op_len;
539
540         if (map_perm & LDC_MAP_R)
541                 memcpy(req_buf, buf, len);
542
543         spin_lock_irqsave(&port->vio.lock, flags);
544
545         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
546
547         /* XXX If we want to use this code generically we have to
548          * XXX handle TX ring exhaustion etc.
549          */
550         desc = vio_dring_cur(dr);
551
552         err = ldc_map_single(port->vio.lp, req_buf, op_len,
553                              desc->cookies, port->ring_cookies,
554                              map_perm);
555         if (err < 0) {
556                 spin_unlock_irqrestore(&port->vio.lock, flags);
557                 kfree(req_buf);
558                 return err;
559         }
560
561         init_completion(&comp.com);
562         comp.waiting_for = WAITING_FOR_GEN_CMD;
563         port->vio.cmp = &comp;
564
565         desc->hdr.ack = VIO_ACK_ENABLE;
566         desc->req_id = port->req_id;
567         desc->operation = op;
568         desc->slice = 0;
569         desc->status = ~0;
570         desc->offset = 0;
571         desc->size = op_len;
572         desc->ncookies = err;
573
574         /* This has to be a non-SMP write barrier because we are writing
575          * to memory which is shared with the peer LDOM.
576          */
577         wmb();
578         desc->hdr.state = VIO_DESC_READY;
579
580         err = __vdc_tx_trigger(port);
581         if (err >= 0) {
582                 port->req_id++;
583                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
584                 spin_unlock_irqrestore(&port->vio.lock, flags);
585
586                 wait_for_completion(&comp.com);
587                 err = comp.err;
588         } else {
589                 port->vio.cmp = NULL;
590                 spin_unlock_irqrestore(&port->vio.lock, flags);
591         }
592
593         if (map_perm & LDC_MAP_W)
594                 memcpy(buf, req_buf, len);
595
596         kfree(req_buf);
597
598         return err;
599 }
600
601 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
602 {
603         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
604         unsigned long len, entry_size;
605         int ncookies;
606         void *dring;
607
608         entry_size = sizeof(struct vio_disk_desc) +
609                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
610         len = (VDC_TX_RING_SIZE * entry_size);
611
612         ncookies = VIO_MAX_RING_COOKIES;
613         dring = ldc_alloc_exp_dring(port->vio.lp, len,
614                                     dr->cookies, &ncookies,
615                                     (LDC_MAP_SHADOW |
616                                      LDC_MAP_DIRECT |
617                                      LDC_MAP_RW));
618         if (IS_ERR(dring))
619                 return PTR_ERR(dring);
620
621         dr->base = dring;
622         dr->entry_size = entry_size;
623         dr->num_entries = VDC_TX_RING_SIZE;
624         dr->prod = dr->cons = 0;
625         dr->pending = VDC_TX_RING_SIZE;
626         dr->ncookies = ncookies;
627
628         return 0;
629 }
630
631 static void vdc_free_tx_ring(struct vdc_port *port)
632 {
633         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
634
635         if (dr->base) {
636                 ldc_free_exp_dring(port->vio.lp, dr->base,
637                                    (dr->entry_size * dr->num_entries),
638                                    dr->cookies, dr->ncookies);
639                 dr->base = NULL;
640                 dr->entry_size = 0;
641                 dr->num_entries = 0;
642                 dr->pending = 0;
643                 dr->ncookies = 0;
644         }
645 }
646
647 static int probe_disk(struct vdc_port *port)
648 {
649         struct vio_completion comp;
650         struct request_queue *q;
651         struct gendisk *g;
652         int err;
653
654         init_completion(&comp.com);
655         comp.err = 0;
656         comp.waiting_for = WAITING_FOR_LINK_UP;
657         port->vio.cmp = &comp;
658
659         vio_port_up(&port->vio);
660
661         wait_for_completion(&comp.com);
662         if (comp.err)
663                 return comp.err;
664
665         err = generic_request(port, VD_OP_GET_VTOC,
666                               &port->label, sizeof(port->label));
667         if (err < 0) {
668                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
669                 return err;
670         }
671
672         err = generic_request(port, VD_OP_GET_DISKGEOM,
673                               &port->geom, sizeof(port->geom));
674         if (err < 0) {
675                 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
676                        "error %d\n", err);
677                 return err;
678         }
679
680         port->vdisk_size = ((u64)port->geom.num_cyl *
681                             (u64)port->geom.num_hd *
682                             (u64)port->geom.num_sec);
683
684         q = blk_init_queue(do_vdc_request, &port->vio.lock);
685         if (!q) {
686                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
687                        port->vio.name);
688                 return -ENOMEM;
689         }
690         g = alloc_disk(1 << PARTITION_SHIFT);
691         if (!g) {
692                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
693                        port->vio.name);
694                 blk_cleanup_queue(q);
695                 return -ENOMEM;
696         }
697
698         port->disk = g;
699
700         blk_queue_max_hw_segments(q, port->ring_cookies);
701         blk_queue_max_phys_segments(q, port->ring_cookies);
702         blk_queue_max_sectors(q, port->max_xfer_size);
703         g->major = vdc_major;
704         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
705         strcpy(g->disk_name, port->disk_name);
706
707         g->fops = &vdc_fops;
708         g->queue = q;
709         g->private_data = port;
710         g->driverfs_dev = &port->vio.vdev->dev;
711
712         set_capacity(g, port->vdisk_size);
713
714         printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
715                g->disk_name,
716                port->vdisk_size, (port->vdisk_size >> (20 - 9)));
717
718         add_disk(g);
719
720         return 0;
721 }
722
723 static struct ldc_channel_config vdc_ldc_cfg = {
724         .event          = vdc_event,
725         .mtu            = 64,
726         .mode           = LDC_MODE_UNRELIABLE,
727 };
728
729 static struct vio_driver_ops vdc_vio_ops = {
730         .send_attr              = vdc_send_attr,
731         .handle_attr            = vdc_handle_attr,
732         .handshake_complete     = vdc_handshake_complete,
733 };
734
735 static void __devinit print_version(void)
736 {
737         static int version_printed;
738
739         if (version_printed++ == 0)
740                 printk(KERN_INFO "%s", version);
741 }
742
743 static int __devinit vdc_port_probe(struct vio_dev *vdev,
744                                     const struct vio_device_id *id)
745 {
746         struct mdesc_handle *hp;
747         struct vdc_port *port;
748         int err;
749
750         print_version();
751
752         hp = mdesc_grab();
753
754         err = -ENODEV;
755         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
756                 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
757                        vdev->dev_no);
758                 goto err_out_release_mdesc;
759         }
760
761         port = kzalloc(sizeof(*port), GFP_KERNEL);
762         err = -ENOMEM;
763         if (!port) {
764                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
765                 goto err_out_release_mdesc;
766         }
767
768         if (vdev->dev_no >= 26)
769                 snprintf(port->disk_name, sizeof(port->disk_name),
770                          VDCBLK_NAME "%c%c",
771                          'a' + ((int)vdev->dev_no / 26) - 1,
772                          'a' + ((int)vdev->dev_no % 26));
773         else
774                 snprintf(port->disk_name, sizeof(port->disk_name),
775                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
776
777         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
778                               vdc_versions, ARRAY_SIZE(vdc_versions),
779                               &vdc_vio_ops, port->disk_name);
780         if (err)
781                 goto err_out_free_port;
782
783         port->vdisk_block_size = 512;
784         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
785         port->ring_cookies = ((port->max_xfer_size *
786                                port->vdisk_block_size) / PAGE_SIZE) + 2;
787
788         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
789         if (err)
790                 goto err_out_free_port;
791
792         err = vdc_alloc_tx_ring(port);
793         if (err)
794                 goto err_out_free_ldc;
795
796         err = probe_disk(port);
797         if (err)
798                 goto err_out_free_tx_ring;
799
800         dev_set_drvdata(&vdev->dev, port);
801
802         mdesc_release(hp);
803
804         return 0;
805
806 err_out_free_tx_ring:
807         vdc_free_tx_ring(port);
808
809 err_out_free_ldc:
810         vio_ldc_free(&port->vio);
811
812 err_out_free_port:
813         kfree(port);
814
815 err_out_release_mdesc:
816         mdesc_release(hp);
817         return err;
818 }
819
820 static int vdc_port_remove(struct vio_dev *vdev)
821 {
822         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
823
824         if (port) {
825                 del_timer_sync(&port->vio.timer);
826
827                 vdc_free_tx_ring(port);
828                 vio_ldc_free(&port->vio);
829
830                 dev_set_drvdata(&vdev->dev, NULL);
831
832                 kfree(port);
833         }
834         return 0;
835 }
836
837 static struct vio_device_id vdc_port_match[] = {
838         {
839                 .type = "vdc-port",
840         },
841         {},
842 };
843 MODULE_DEVICE_TABLE(vio, vdc_port_match);
844
845 static struct vio_driver vdc_port_driver = {
846         .id_table       = vdc_port_match,
847         .probe          = vdc_port_probe,
848         .remove         = vdc_port_remove,
849         .driver         = {
850                 .name   = "vdc_port",
851                 .owner  = THIS_MODULE,
852         }
853 };
854
855 static int __init vdc_init(void)
856 {
857         int err;
858
859         err = register_blkdev(0, VDCBLK_NAME);
860         if (err < 0)
861                 goto out_err;
862
863         vdc_major = err;
864
865         err = vio_register_driver(&vdc_port_driver);
866         if (err)
867                 goto out_unregister_blkdev;
868
869         return 0;
870
871 out_unregister_blkdev:
872         unregister_blkdev(vdc_major, VDCBLK_NAME);
873         vdc_major = 0;
874
875 out_err:
876         return err;
877 }
878
879 static void __exit vdc_exit(void)
880 {
881         vio_unregister_driver(&vdc_port_driver);
882         unregister_blkdev(vdc_major, VDCBLK_NAME);
883 }
884
885 module_init(vdc_init);
886 module_exit(vdc_exit);