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