Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
[pandora-kernel.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         nsg = blk_rq_map_sg(req->q, req, sg);
392
393         len = 0;
394         for (i = 0; i < nsg; i++)
395                 len += sg[i].length;
396
397         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
398                 blk_stop_queue(port->disk->queue);
399                 err = -ENOMEM;
400                 goto out;
401         }
402
403         desc = vio_dring_cur(dr);
404
405         err = ldc_map_sg(port->vio.lp, sg, nsg,
406                          desc->cookies, port->ring_cookies,
407                          map_perm);
408         if (err < 0) {
409                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
410                 return err;
411         }
412
413         rqe = &port->rq_arr[dr->prod];
414         rqe->req = req;
415
416         desc->hdr.ack = VIO_ACK_ENABLE;
417         desc->req_id = port->req_id;
418         desc->operation = op;
419         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
420                 desc->slice = 2;
421         } else {
422                 desc->slice = 0;
423         }
424         desc->status = ~0;
425         desc->offset = (req->sector << 9) / port->vdisk_block_size;
426         desc->size = len;
427         desc->ncookies = err;
428
429         /* This has to be a non-SMP write barrier because we are writing
430          * to memory which is shared with the peer LDOM.
431          */
432         wmb();
433         desc->hdr.state = VIO_DESC_READY;
434
435         err = __vdc_tx_trigger(port);
436         if (err < 0) {
437                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
438         } else {
439                 port->req_id++;
440                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
441         }
442 out:
443
444         return err;
445 }
446
447 static void do_vdc_request(request_queue_t *q)
448 {
449         while (1) {
450                 struct request *req = elv_next_request(q);
451
452                 if (!req)
453                         break;
454
455                 blkdev_dequeue_request(req);
456                 if (__send_request(req) < 0)
457                         vdc_end_request(req, 0, req->hard_nr_sectors);
458         }
459 }
460
461 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
462 {
463         struct vio_dring_state *dr;
464         struct vio_completion comp;
465         struct vio_disk_desc *desc;
466         unsigned int map_perm;
467         unsigned long flags;
468         int op_len, err;
469         void *req_buf;
470
471         if (!(((u64)1 << ((u64)op - 1)) & port->operations))
472                 return -EOPNOTSUPP;
473
474         switch (op) {
475         case VD_OP_BREAD:
476         case VD_OP_BWRITE:
477         default:
478                 return -EINVAL;
479
480         case VD_OP_FLUSH:
481                 op_len = 0;
482                 map_perm = 0;
483                 break;
484
485         case VD_OP_GET_WCE:
486                 op_len = sizeof(u32);
487                 map_perm = LDC_MAP_W;
488                 break;
489
490         case VD_OP_SET_WCE:
491                 op_len = sizeof(u32);
492                 map_perm = LDC_MAP_R;
493                 break;
494
495         case VD_OP_GET_VTOC:
496                 op_len = sizeof(struct vio_disk_vtoc);
497                 map_perm = LDC_MAP_W;
498                 break;
499
500         case VD_OP_SET_VTOC:
501                 op_len = sizeof(struct vio_disk_vtoc);
502                 map_perm = LDC_MAP_R;
503                 break;
504
505         case VD_OP_GET_DISKGEOM:
506                 op_len = sizeof(struct vio_disk_geom);
507                 map_perm = LDC_MAP_W;
508                 break;
509
510         case VD_OP_SET_DISKGEOM:
511                 op_len = sizeof(struct vio_disk_geom);
512                 map_perm = LDC_MAP_R;
513                 break;
514
515         case VD_OP_SCSICMD:
516                 op_len = 16;
517                 map_perm = LDC_MAP_RW;
518                 break;
519
520         case VD_OP_GET_DEVID:
521                 op_len = sizeof(struct vio_disk_devid);
522                 map_perm = LDC_MAP_W;
523                 break;
524
525         case VD_OP_GET_EFI:
526         case VD_OP_SET_EFI:
527                 return -EOPNOTSUPP;
528                 break;
529         };
530
531         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
532
533         op_len = (op_len + 7) & ~7;
534         req_buf = kzalloc(op_len, GFP_KERNEL);
535         if (!req_buf)
536                 return -ENOMEM;
537
538         if (len > op_len)
539                 len = op_len;
540
541         if (map_perm & LDC_MAP_R)
542                 memcpy(req_buf, buf, len);
543
544         spin_lock_irqsave(&port->vio.lock, flags);
545
546         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
547
548         /* XXX If we want to use this code generically we have to
549          * XXX handle TX ring exhaustion etc.
550          */
551         desc = vio_dring_cur(dr);
552
553         err = ldc_map_single(port->vio.lp, req_buf, op_len,
554                              desc->cookies, port->ring_cookies,
555                              map_perm);
556         if (err < 0) {
557                 spin_unlock_irqrestore(&port->vio.lock, flags);
558                 kfree(req_buf);
559                 return err;
560         }
561
562         init_completion(&comp.com);
563         comp.waiting_for = WAITING_FOR_GEN_CMD;
564         port->vio.cmp = &comp;
565
566         desc->hdr.ack = VIO_ACK_ENABLE;
567         desc->req_id = port->req_id;
568         desc->operation = op;
569         desc->slice = 0;
570         desc->status = ~0;
571         desc->offset = 0;
572         desc->size = op_len;
573         desc->ncookies = err;
574
575         /* This has to be a non-SMP write barrier because we are writing
576          * to memory which is shared with the peer LDOM.
577          */
578         wmb();
579         desc->hdr.state = VIO_DESC_READY;
580
581         err = __vdc_tx_trigger(port);
582         if (err >= 0) {
583                 port->req_id++;
584                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
585                 spin_unlock_irqrestore(&port->vio.lock, flags);
586
587                 wait_for_completion(&comp.com);
588                 err = comp.err;
589         } else {
590                 port->vio.cmp = NULL;
591                 spin_unlock_irqrestore(&port->vio.lock, flags);
592         }
593
594         if (map_perm & LDC_MAP_W)
595                 memcpy(buf, req_buf, len);
596
597         kfree(req_buf);
598
599         return err;
600 }
601
602 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
603 {
604         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
605         unsigned long len, entry_size;
606         int ncookies;
607         void *dring;
608
609         entry_size = sizeof(struct vio_disk_desc) +
610                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
611         len = (VDC_TX_RING_SIZE * entry_size);
612
613         ncookies = VIO_MAX_RING_COOKIES;
614         dring = ldc_alloc_exp_dring(port->vio.lp, len,
615                                     dr->cookies, &ncookies,
616                                     (LDC_MAP_SHADOW |
617                                      LDC_MAP_DIRECT |
618                                      LDC_MAP_RW));
619         if (IS_ERR(dring))
620                 return PTR_ERR(dring);
621
622         dr->base = dring;
623         dr->entry_size = entry_size;
624         dr->num_entries = VDC_TX_RING_SIZE;
625         dr->prod = dr->cons = 0;
626         dr->pending = VDC_TX_RING_SIZE;
627         dr->ncookies = ncookies;
628
629         return 0;
630 }
631
632 static void vdc_free_tx_ring(struct vdc_port *port)
633 {
634         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
635
636         if (dr->base) {
637                 ldc_free_exp_dring(port->vio.lp, dr->base,
638                                    (dr->entry_size * dr->num_entries),
639                                    dr->cookies, dr->ncookies);
640                 dr->base = NULL;
641                 dr->entry_size = 0;
642                 dr->num_entries = 0;
643                 dr->pending = 0;
644                 dr->ncookies = 0;
645         }
646 }
647
648 static int probe_disk(struct vdc_port *port)
649 {
650         struct vio_completion comp;
651         struct request_queue *q;
652         struct gendisk *g;
653         int err;
654
655         init_completion(&comp.com);
656         comp.err = 0;
657         comp.waiting_for = WAITING_FOR_LINK_UP;
658         port->vio.cmp = &comp;
659
660         vio_port_up(&port->vio);
661
662         wait_for_completion(&comp.com);
663         if (comp.err)
664                 return comp.err;
665
666         err = generic_request(port, VD_OP_GET_VTOC,
667                               &port->label, sizeof(port->label));
668         if (err < 0) {
669                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
670                 return err;
671         }
672
673         err = generic_request(port, VD_OP_GET_DISKGEOM,
674                               &port->geom, sizeof(port->geom));
675         if (err < 0) {
676                 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
677                        "error %d\n", err);
678                 return err;
679         }
680
681         port->vdisk_size = ((u64)port->geom.num_cyl *
682                             (u64)port->geom.num_hd *
683                             (u64)port->geom.num_sec);
684
685         q = blk_init_queue(do_vdc_request, &port->vio.lock);
686         if (!q) {
687                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
688                        port->vio.name);
689                 return -ENOMEM;
690         }
691         g = alloc_disk(1 << PARTITION_SHIFT);
692         if (!g) {
693                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
694                        port->vio.name);
695                 blk_cleanup_queue(q);
696                 return -ENOMEM;
697         }
698
699         port->disk = g;
700
701         blk_queue_max_hw_segments(q, port->ring_cookies);
702         blk_queue_max_phys_segments(q, port->ring_cookies);
703         blk_queue_max_sectors(q, port->max_xfer_size);
704         g->major = vdc_major;
705         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
706         strcpy(g->disk_name, port->disk_name);
707
708         g->fops = &vdc_fops;
709         g->queue = q;
710         g->private_data = port;
711         g->driverfs_dev = &port->vio.vdev->dev;
712
713         set_capacity(g, port->vdisk_size);
714
715         printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
716                g->disk_name,
717                port->vdisk_size, (port->vdisk_size >> (20 - 9)));
718
719         add_disk(g);
720
721         return 0;
722 }
723
724 static struct ldc_channel_config vdc_ldc_cfg = {
725         .event          = vdc_event,
726         .mtu            = 64,
727         .mode           = LDC_MODE_UNRELIABLE,
728 };
729
730 static struct vio_driver_ops vdc_vio_ops = {
731         .send_attr              = vdc_send_attr,
732         .handle_attr            = vdc_handle_attr,
733         .handshake_complete     = vdc_handshake_complete,
734 };
735
736 static void print_version(void)
737 {
738         static int version_printed;
739
740         if (version_printed++ == 0)
741                 printk(KERN_INFO "%s", version);
742 }
743
744 static int __devinit vdc_port_probe(struct vio_dev *vdev,
745                                     const struct vio_device_id *id)
746 {
747         struct mdesc_handle *hp;
748         struct vdc_port *port;
749         int err;
750
751         print_version();
752
753         hp = mdesc_grab();
754
755         err = -ENODEV;
756         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
757                 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
758                        vdev->dev_no);
759                 goto err_out_release_mdesc;
760         }
761
762         port = kzalloc(sizeof(*port), GFP_KERNEL);
763         err = -ENOMEM;
764         if (!port) {
765                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
766                 goto err_out_release_mdesc;
767         }
768
769         if (vdev->dev_no >= 26)
770                 snprintf(port->disk_name, sizeof(port->disk_name),
771                          VDCBLK_NAME "%c%c",
772                          'a' + ((int)vdev->dev_no / 26) - 1,
773                          'a' + ((int)vdev->dev_no % 26));
774         else
775                 snprintf(port->disk_name, sizeof(port->disk_name),
776                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
777
778         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
779                               vdc_versions, ARRAY_SIZE(vdc_versions),
780                               &vdc_vio_ops, port->disk_name);
781         if (err)
782                 goto err_out_free_port;
783
784         port->vdisk_block_size = 512;
785         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
786         port->ring_cookies = ((port->max_xfer_size *
787                                port->vdisk_block_size) / PAGE_SIZE) + 2;
788
789         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
790         if (err)
791                 goto err_out_free_port;
792
793         err = vdc_alloc_tx_ring(port);
794         if (err)
795                 goto err_out_free_ldc;
796
797         err = probe_disk(port);
798         if (err)
799                 goto err_out_free_tx_ring;
800
801         dev_set_drvdata(&vdev->dev, port);
802
803         mdesc_release(hp);
804
805         return 0;
806
807 err_out_free_tx_ring:
808         vdc_free_tx_ring(port);
809
810 err_out_free_ldc:
811         vio_ldc_free(&port->vio);
812
813 err_out_free_port:
814         kfree(port);
815
816 err_out_release_mdesc:
817         mdesc_release(hp);
818         return err;
819 }
820
821 static int vdc_port_remove(struct vio_dev *vdev)
822 {
823         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
824
825         if (port) {
826                 del_timer_sync(&port->vio.timer);
827
828                 vdc_free_tx_ring(port);
829                 vio_ldc_free(&port->vio);
830
831                 dev_set_drvdata(&vdev->dev, NULL);
832
833                 kfree(port);
834         }
835         return 0;
836 }
837
838 static struct vio_device_id vdc_port_match[] = {
839         {
840                 .type = "vdc-port",
841         },
842         {},
843 };
844 MODULE_DEVICE_TABLE(vio, vdc_port_match);
845
846 static struct vio_driver vdc_port_driver = {
847         .id_table       = vdc_port_match,
848         .probe          = vdc_port_probe,
849         .remove         = vdc_port_remove,
850         .driver         = {
851                 .name   = "vdc_port",
852                 .owner  = THIS_MODULE,
853         }
854 };
855
856 static int __init vdc_init(void)
857 {
858         int err;
859
860         err = register_blkdev(0, VDCBLK_NAME);
861         if (err < 0)
862                 goto out_err;
863
864         vdc_major = err;
865
866         err = vio_register_driver(&vdc_port_driver);
867         if (err)
868                 goto out_unregister_blkdev;
869
870         return 0;
871
872 out_unregister_blkdev:
873         unregister_blkdev(vdc_major, VDCBLK_NAME);
874         vdc_major = 0;
875
876 out_err:
877         return err;
878 }
879
880 static void __exit vdc_exit(void)
881 {
882         vio_unregister_driver(&vdc_port_driver);
883         unregister_blkdev(vdc_major, VDCBLK_NAME);
884 }
885
886 module_init(vdc_init);
887 module_exit(vdc_exit);