firmware: Sigma: Fix endianess issues
[linux-2.6.git] / drivers / block / viodasd.c
1 /* -*- linux-c -*-
2  * viodasd.c
3  *  Authors: Dave Boutcher <boutcher@us.ibm.com>
4  *           Ryan Arnold <ryanarn@us.ibm.com>
5  *           Colin Devilbiss <devilbis@us.ibm.com>
6  *           Stephen Rothwell
7  *
8  * (C) Copyright 2000-2004 IBM Corporation
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of the
13  * License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  * This routine provides access to disk space (termed "DASD" in historical
25  * IBM terms) owned and managed by an OS/400 partition running on the
26  * same box as this Linux partition.
27  *
28  * All disk operations are performed by sending messages back and forth to
29  * the OS/400 partition.
30  */
31
32 #define pr_fmt(fmt) "viod: " fmt
33
34 #include <linux/major.h>
35 #include <linux/fs.h>
36 #include <linux/module.h>
37 #include <linux/kernel.h>
38 #include <linux/blkdev.h>
39 #include <linux/genhd.h>
40 #include <linux/hdreg.h>
41 #include <linux/errno.h>
42 #include <linux/init.h>
43 #include <linux/string.h>
44 #include <linux/mutex.h>
45 #include <linux/dma-mapping.h>
46 #include <linux/completion.h>
47 #include <linux/device.h>
48 #include <linux/scatterlist.h>
49
50 #include <asm/uaccess.h>
51 #include <asm/vio.h>
52 #include <asm/iseries/hv_types.h>
53 #include <asm/iseries/hv_lp_event.h>
54 #include <asm/iseries/hv_lp_config.h>
55 #include <asm/iseries/vio.h>
56 #include <asm/firmware.h>
57
58 MODULE_DESCRIPTION("iSeries Virtual DASD");
59 MODULE_AUTHOR("Dave Boutcher");
60 MODULE_LICENSE("GPL");
61
62 /*
63  * We only support 7 partitions per physical disk....so with minor
64  * numbers 0-255 we get a maximum of 32 disks.
65  */
66 #define VIOD_GENHD_NAME         "iseries/vd"
67
68 #define VIOD_VERS               "1.64"
69
70 enum {
71         PARTITION_SHIFT = 3,
72         MAX_DISKNO = HVMAXARCHITECTEDVIRTUALDISKS,
73         MAX_DISK_NAME = FIELD_SIZEOF(struct gendisk, disk_name)
74 };
75
76 static DEFINE_MUTEX(viodasd_mutex);
77 static DEFINE_SPINLOCK(viodasd_spinlock);
78
79 #define VIOMAXREQ               16
80
81 #define DEVICE_NO(cell) ((struct viodasd_device *)(cell) - &viodasd_devices[0])
82
83 struct viodasd_waitevent {
84         struct completion       com;
85         int                     rc;
86         u16                     sub_result;
87         int                     max_disk;       /* open */
88 };
89
90 static const struct vio_error_entry viodasd_err_table[] = {
91         { 0x0201, EINVAL, "Invalid Range" },
92         { 0x0202, EINVAL, "Invalid Token" },
93         { 0x0203, EIO, "DMA Error" },
94         { 0x0204, EIO, "Use Error" },
95         { 0x0205, EIO, "Release Error" },
96         { 0x0206, EINVAL, "Invalid Disk" },
97         { 0x0207, EBUSY, "Can't Lock" },
98         { 0x0208, EIO, "Already Locked" },
99         { 0x0209, EIO, "Already Unlocked" },
100         { 0x020A, EIO, "Invalid Arg" },
101         { 0x020B, EIO, "Bad IFS File" },
102         { 0x020C, EROFS, "Read Only Device" },
103         { 0x02FF, EIO, "Internal Error" },
104         { 0x0000, 0, NULL },
105 };
106
107 /*
108  * Figure out the biggest I/O request (in sectors) we can accept
109  */
110 #define VIODASD_MAXSECTORS (4096 / 512 * VIOMAXBLOCKDMA)
111
112 /*
113  * Number of disk I/O requests we've sent to OS/400
114  */
115 static int num_req_outstanding;
116
117 /*
118  * This is our internal structure for keeping track of disk devices
119  */
120 struct viodasd_device {
121         u16             cylinders;
122         u16             tracks;
123         u16             sectors;
124         u16             bytes_per_sector;
125         u64             size;
126         int             read_only;
127         spinlock_t      q_lock;
128         struct gendisk  *disk;
129         struct device   *dev;
130 } viodasd_devices[MAX_DISKNO];
131
132 /*
133  * External open entry point.
134  */
135 static int viodasd_open(struct block_device *bdev, fmode_t mode)
136 {
137         struct viodasd_device *d = bdev->bd_disk->private_data;
138         HvLpEvent_Rc hvrc;
139         struct viodasd_waitevent we;
140         u16 flags = 0;
141
142         if (d->read_only) {
143                 if (mode & FMODE_WRITE)
144                         return -EROFS;
145                 flags = vioblockflags_ro;
146         }
147
148         init_completion(&we.com);
149
150         /* Send the open event to OS/400 */
151         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
152                         HvLpEvent_Type_VirtualIo,
153                         viomajorsubtype_blockio | vioblockopen,
154                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
155                         viopath_sourceinst(viopath_hostLp),
156                         viopath_targetinst(viopath_hostLp),
157                         (u64)(unsigned long)&we, VIOVERSION << 16,
158                         ((u64)DEVICE_NO(d) << 48) | ((u64)flags << 32),
159                         0, 0, 0);
160         if (hvrc != 0) {
161                 pr_warning("HV open failed %d\n", (int)hvrc);
162                 return -EIO;
163         }
164
165         wait_for_completion(&we.com);
166
167         /* Check the return code */
168         if (we.rc != 0) {
169                 const struct vio_error_entry *err =
170                         vio_lookup_rc(viodasd_err_table, we.sub_result);
171
172                 pr_warning("bad rc opening disk: %d:0x%04x (%s)\n",
173                            (int)we.rc, we.sub_result, err->msg);
174                 return -EIO;
175         }
176
177         return 0;
178 }
179
180 static int viodasd_unlocked_open(struct block_device *bdev, fmode_t mode)
181 {
182         int ret;
183
184         mutex_lock(&viodasd_mutex);
185         ret = viodasd_open(bdev, mode);
186         mutex_unlock(&viodasd_mutex);
187
188         return ret;
189 }
190
191
192 /*
193  * External release entry point.
194  */
195 static int viodasd_release(struct gendisk *disk, fmode_t mode)
196 {
197         struct viodasd_device *d = disk->private_data;
198         HvLpEvent_Rc hvrc;
199
200         mutex_lock(&viodasd_mutex);
201         /* Send the event to OS/400.  We DON'T expect a response */
202         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
203                         HvLpEvent_Type_VirtualIo,
204                         viomajorsubtype_blockio | vioblockclose,
205                         HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
206                         viopath_sourceinst(viopath_hostLp),
207                         viopath_targetinst(viopath_hostLp),
208                         0, VIOVERSION << 16,
209                         ((u64)DEVICE_NO(d) << 48) /* | ((u64)flags << 32) */,
210                         0, 0, 0);
211         if (hvrc != 0)
212                 pr_warning("HV close call failed %d\n", (int)hvrc);
213
214         mutex_unlock(&viodasd_mutex);
215
216         return 0;
217 }
218
219
220 /* External ioctl entry point.
221  */
222 static int viodasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
223 {
224         struct gendisk *disk = bdev->bd_disk;
225         struct viodasd_device *d = disk->private_data;
226
227         geo->sectors = d->sectors ? d->sectors : 32;
228         geo->heads = d->tracks ? d->tracks  : 64;
229         geo->cylinders = d->cylinders ? d->cylinders :
230                 get_capacity(disk) / (geo->sectors * geo->heads);
231
232         return 0;
233 }
234
235 /*
236  * Our file operations table
237  */
238 static const struct block_device_operations viodasd_fops = {
239         .owner = THIS_MODULE,
240         .open = viodasd_unlocked_open,
241         .release = viodasd_release,
242         .getgeo = viodasd_getgeo,
243 };
244
245 /*
246  * End a request
247  */
248 static void viodasd_end_request(struct request *req, int error,
249                 int num_sectors)
250 {
251         __blk_end_request(req, error, num_sectors << 9);
252 }
253
254 /*
255  * Send an actual I/O request to OS/400
256  */
257 static int send_request(struct request *req)
258 {
259         u64 start;
260         int direction;
261         int nsg;
262         u16 viocmd;
263         HvLpEvent_Rc hvrc;
264         struct vioblocklpevent *bevent;
265         struct HvLpEvent *hev;
266         struct scatterlist sg[VIOMAXBLOCKDMA];
267         int sgindex;
268         struct viodasd_device *d;
269         unsigned long flags;
270
271         start = (u64)blk_rq_pos(req) << 9;
272
273         if (rq_data_dir(req) == READ) {
274                 direction = DMA_FROM_DEVICE;
275                 viocmd = viomajorsubtype_blockio | vioblockread;
276         } else {
277                 direction = DMA_TO_DEVICE;
278                 viocmd = viomajorsubtype_blockio | vioblockwrite;
279         }
280
281         d = req->rq_disk->private_data;
282
283         /* Now build the scatter-gather list */
284         sg_init_table(sg, VIOMAXBLOCKDMA);
285         nsg = blk_rq_map_sg(req->q, req, sg);
286         nsg = dma_map_sg(d->dev, sg, nsg, direction);
287
288         spin_lock_irqsave(&viodasd_spinlock, flags);
289         num_req_outstanding++;
290
291         /* This optimization handles a single DMA block */
292         if (nsg == 1)
293                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
294                                 HvLpEvent_Type_VirtualIo, viocmd,
295                                 HvLpEvent_AckInd_DoAck,
296                                 HvLpEvent_AckType_ImmediateAck,
297                                 viopath_sourceinst(viopath_hostLp),
298                                 viopath_targetinst(viopath_hostLp),
299                                 (u64)(unsigned long)req, VIOVERSION << 16,
300                                 ((u64)DEVICE_NO(d) << 48), start,
301                                 ((u64)sg_dma_address(&sg[0])) << 32,
302                                 sg_dma_len(&sg[0]));
303         else {
304                 bevent = (struct vioblocklpevent *)
305                         vio_get_event_buffer(viomajorsubtype_blockio);
306                 if (bevent == NULL) {
307                         pr_warning("error allocating disk event buffer\n");
308                         goto error_ret;
309                 }
310
311                 /*
312                  * Now build up the actual request.  Note that we store
313                  * the pointer to the request in the correlation
314                  * token so we can match the response up later
315                  */
316                 memset(bevent, 0, sizeof(struct vioblocklpevent));
317                 hev = &bevent->event;
318                 hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DO_ACK |
319                         HV_LP_EVENT_INT;
320                 hev->xType = HvLpEvent_Type_VirtualIo;
321                 hev->xSubtype = viocmd;
322                 hev->xSourceLp = HvLpConfig_getLpIndex();
323                 hev->xTargetLp = viopath_hostLp;
324                 hev->xSizeMinus1 =
325                         offsetof(struct vioblocklpevent, u.rw_data.dma_info) +
326                         (sizeof(bevent->u.rw_data.dma_info[0]) * nsg) - 1;
327                 hev->xSourceInstanceId = viopath_sourceinst(viopath_hostLp);
328                 hev->xTargetInstanceId = viopath_targetinst(viopath_hostLp);
329                 hev->xCorrelationToken = (u64)req;
330                 bevent->version = VIOVERSION;
331                 bevent->disk = DEVICE_NO(d);
332                 bevent->u.rw_data.offset = start;
333
334                 /*
335                  * Copy just the dma information from the sg list
336                  * into the request
337                  */
338                 for (sgindex = 0; sgindex < nsg; sgindex++) {
339                         bevent->u.rw_data.dma_info[sgindex].token =
340                                 sg_dma_address(&sg[sgindex]);
341                         bevent->u.rw_data.dma_info[sgindex].len =
342                                 sg_dma_len(&sg[sgindex]);
343                 }
344
345                 /* Send the request */
346                 hvrc = HvCallEvent_signalLpEvent(&bevent->event);
347                 vio_free_event_buffer(viomajorsubtype_blockio, bevent);
348         }
349
350         if (hvrc != HvLpEvent_Rc_Good) {
351                 pr_warning("error sending disk event to OS/400 (rc %d)\n",
352                            (int)hvrc);
353                 goto error_ret;
354         }
355         spin_unlock_irqrestore(&viodasd_spinlock, flags);
356         return 0;
357
358 error_ret:
359         num_req_outstanding--;
360         spin_unlock_irqrestore(&viodasd_spinlock, flags);
361         dma_unmap_sg(d->dev, sg, nsg, direction);
362         return -1;
363 }
364
365 /*
366  * This is the external request processing routine
367  */
368 static void do_viodasd_request(struct request_queue *q)
369 {
370         struct request *req;
371
372         /*
373          * If we already have the maximum number of requests
374          * outstanding to OS/400 just bail out. We'll come
375          * back later.
376          */
377         while (num_req_outstanding < VIOMAXREQ) {
378                 req = blk_fetch_request(q);
379                 if (req == NULL)
380                         return;
381                 /* check that request contains a valid command */
382                 if (req->cmd_type != REQ_TYPE_FS) {
383                         viodasd_end_request(req, -EIO, blk_rq_sectors(req));
384                         continue;
385                 }
386                 /* Try sending the request */
387                 if (send_request(req) != 0)
388                         viodasd_end_request(req, -EIO, blk_rq_sectors(req));
389         }
390 }
391
392 /*
393  * Probe a single disk and fill in the viodasd_device structure
394  * for it.
395  */
396 static int probe_disk(struct viodasd_device *d)
397 {
398         HvLpEvent_Rc hvrc;
399         struct viodasd_waitevent we;
400         int dev_no = DEVICE_NO(d);
401         struct gendisk *g;
402         struct request_queue *q;
403         u16 flags = 0;
404
405 retry:
406         init_completion(&we.com);
407
408         /* Send the open event to OS/400 */
409         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
410                         HvLpEvent_Type_VirtualIo,
411                         viomajorsubtype_blockio | vioblockopen,
412                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
413                         viopath_sourceinst(viopath_hostLp),
414                         viopath_targetinst(viopath_hostLp),
415                         (u64)(unsigned long)&we, VIOVERSION << 16,
416                         ((u64)dev_no << 48) | ((u64)flags<< 32),
417                         0, 0, 0);
418         if (hvrc != 0) {
419                 pr_warning("bad rc on HV open %d\n", (int)hvrc);
420                 return 0;
421         }
422
423         wait_for_completion(&we.com);
424
425         if (we.rc != 0) {
426                 if (flags != 0)
427                         return 0;
428                 /* try again with read only flag set */
429                 flags = vioblockflags_ro;
430                 goto retry;
431         }
432         if (we.max_disk > (MAX_DISKNO - 1)) {
433                 printk_once(KERN_INFO pr_fmt("Only examining the first %d of %d disks connected\n"),
434                             MAX_DISKNO, we.max_disk + 1);
435         }
436
437         /* Send the close event to OS/400.  We DON'T expect a response */
438         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
439                         HvLpEvent_Type_VirtualIo,
440                         viomajorsubtype_blockio | vioblockclose,
441                         HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
442                         viopath_sourceinst(viopath_hostLp),
443                         viopath_targetinst(viopath_hostLp),
444                         0, VIOVERSION << 16,
445                         ((u64)dev_no << 48) | ((u64)flags << 32),
446                         0, 0, 0);
447         if (hvrc != 0) {
448                 pr_warning("bad rc sending event to OS/400 %d\n", (int)hvrc);
449                 return 0;
450         }
451
452         if (d->dev == NULL) {
453                 /* this is when we reprobe for new disks */
454                 if (vio_create_viodasd(dev_no) == NULL) {
455                         pr_warning("cannot allocate virtual device for disk %d\n",
456                                    dev_no);
457                         return 0;
458                 }
459                 /*
460                  * The vio_create_viodasd will have recursed into this
461                  * routine with d->dev set to the new vio device and
462                  * will finish the setup of the disk below.
463                  */
464                 return 1;
465         }
466
467         /* create the request queue for the disk */
468         spin_lock_init(&d->q_lock);
469         q = blk_init_queue(do_viodasd_request, &d->q_lock);
470         if (q == NULL) {
471                 pr_warning("cannot allocate queue for disk %d\n", dev_no);
472                 return 0;
473         }
474         g = alloc_disk(1 << PARTITION_SHIFT);
475         if (g == NULL) {
476                 pr_warning("cannot allocate disk structure for disk %d\n",
477                            dev_no);
478                 blk_cleanup_queue(q);
479                 return 0;
480         }
481
482         d->disk = g;
483         blk_queue_max_segments(q, VIOMAXBLOCKDMA);
484         blk_queue_max_hw_sectors(q, VIODASD_MAXSECTORS);
485         g->major = VIODASD_MAJOR;
486         g->first_minor = dev_no << PARTITION_SHIFT;
487         if (dev_no >= 26)
488                 snprintf(g->disk_name, sizeof(g->disk_name),
489                                 VIOD_GENHD_NAME "%c%c",
490                                 'a' + (dev_no / 26) - 1, 'a' + (dev_no % 26));
491         else
492                 snprintf(g->disk_name, sizeof(g->disk_name),
493                                 VIOD_GENHD_NAME "%c", 'a' + (dev_no % 26));
494         g->fops = &viodasd_fops;
495         g->queue = q;
496         g->private_data = d;
497         g->driverfs_dev = d->dev;
498         set_capacity(g, d->size >> 9);
499
500         pr_info("disk %d: %lu sectors (%lu MB) CHS=%d/%d/%d sector size %d%s\n",
501                 dev_no, (unsigned long)(d->size >> 9),
502                 (unsigned long)(d->size >> 20),
503                 (int)d->cylinders, (int)d->tracks,
504                 (int)d->sectors, (int)d->bytes_per_sector,
505                 d->read_only ? " (RO)" : "");
506
507         /* register us in the global list */
508         add_disk(g);
509         return 1;
510 }
511
512 /* returns the total number of scatterlist elements converted */
513 static int block_event_to_scatterlist(const struct vioblocklpevent *bevent,
514                 struct scatterlist *sg, int *total_len)
515 {
516         int i, numsg;
517         const struct rw_data *rw_data = &bevent->u.rw_data;
518         static const int offset =
519                 offsetof(struct vioblocklpevent, u.rw_data.dma_info);
520         static const int element_size = sizeof(rw_data->dma_info[0]);
521
522         numsg = ((bevent->event.xSizeMinus1 + 1) - offset) / element_size;
523         if (numsg > VIOMAXBLOCKDMA)
524                 numsg = VIOMAXBLOCKDMA;
525
526         *total_len = 0;
527         sg_init_table(sg, VIOMAXBLOCKDMA);
528         for (i = 0; (i < numsg) && (rw_data->dma_info[i].len > 0); ++i) {
529                 sg_dma_address(&sg[i]) = rw_data->dma_info[i].token;
530                 sg_dma_len(&sg[i]) = rw_data->dma_info[i].len;
531                 *total_len += rw_data->dma_info[i].len;
532         }
533         return i;
534 }
535
536 /*
537  * Restart all queues, starting with the one _after_ the disk given,
538  * thus reducing the chance of starvation of higher numbered disks.
539  */
540 static void viodasd_restart_all_queues_starting_from(int first_index)
541 {
542         int i;
543
544         for (i = first_index + 1; i < MAX_DISKNO; ++i)
545                 if (viodasd_devices[i].disk)
546                         blk_run_queue(viodasd_devices[i].disk->queue);
547         for (i = 0; i <= first_index; ++i)
548                 if (viodasd_devices[i].disk)
549                         blk_run_queue(viodasd_devices[i].disk->queue);
550 }
551
552 /*
553  * For read and write requests, decrement the number of outstanding requests,
554  * Free the DMA buffers we allocated.
555  */
556 static int viodasd_handle_read_write(struct vioblocklpevent *bevent)
557 {
558         int num_sg, num_sect, pci_direction, total_len;
559         struct request *req;
560         struct scatterlist sg[VIOMAXBLOCKDMA];
561         struct HvLpEvent *event = &bevent->event;
562         unsigned long irq_flags;
563         struct viodasd_device *d;
564         int error;
565         spinlock_t *qlock;
566
567         num_sg = block_event_to_scatterlist(bevent, sg, &total_len);
568         num_sect = total_len >> 9;
569         if (event->xSubtype == (viomajorsubtype_blockio | vioblockread))
570                 pci_direction = DMA_FROM_DEVICE;
571         else
572                 pci_direction = DMA_TO_DEVICE;
573         req = (struct request *)bevent->event.xCorrelationToken;
574         d = req->rq_disk->private_data;
575
576         dma_unmap_sg(d->dev, sg, num_sg, pci_direction);
577
578         /*
579          * Since this is running in interrupt mode, we need to make sure
580          * we're not stepping on any global I/O operations
581          */
582         spin_lock_irqsave(&viodasd_spinlock, irq_flags);
583         num_req_outstanding--;
584         spin_unlock_irqrestore(&viodasd_spinlock, irq_flags);
585
586         error = (event->xRc == HvLpEvent_Rc_Good) ? 0 : -EIO;
587         if (error) {
588                 const struct vio_error_entry *err;
589                 err = vio_lookup_rc(viodasd_err_table, bevent->sub_result);
590                 pr_warning("read/write error %d:0x%04x (%s)\n",
591                            event->xRc, bevent->sub_result, err->msg);
592                 num_sect = blk_rq_sectors(req);
593         }
594         qlock = req->q->queue_lock;
595         spin_lock_irqsave(qlock, irq_flags);
596         viodasd_end_request(req, error, num_sect);
597         spin_unlock_irqrestore(qlock, irq_flags);
598
599         /* Finally, try to get more requests off of this device's queue */
600         viodasd_restart_all_queues_starting_from(DEVICE_NO(d));
601
602         return 0;
603 }
604
605 /* This routine handles incoming block LP events */
606 static void handle_block_event(struct HvLpEvent *event)
607 {
608         struct vioblocklpevent *bevent = (struct vioblocklpevent *)event;
609         struct viodasd_waitevent *pwe;
610
611         if (event == NULL)
612                 /* Notification that a partition went away! */
613                 return;
614         /* First, we should NEVER get an int here...only acks */
615         if (hvlpevent_is_int(event)) {
616                 pr_warning("Yikes! got an int in viodasd event handler!\n");
617                 if (hvlpevent_need_ack(event)) {
618                         event->xRc = HvLpEvent_Rc_InvalidSubtype;
619                         HvCallEvent_ackLpEvent(event);
620                 }
621         }
622
623         switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) {
624         case vioblockopen:
625                 /*
626                  * Handle a response to an open request.  We get all the
627                  * disk information in the response, so update it.  The
628                  * correlation token contains a pointer to a waitevent
629                  * structure that has a completion in it.  update the
630                  * return code in the waitevent structure and post the
631                  * completion to wake up the guy who sent the request
632                  */
633                 pwe = (struct viodasd_waitevent *)event->xCorrelationToken;
634                 pwe->rc = event->xRc;
635                 pwe->sub_result = bevent->sub_result;
636                 if (event->xRc == HvLpEvent_Rc_Good) {
637                         const struct open_data *data = &bevent->u.open_data;
638                         struct viodasd_device *device =
639                                 &viodasd_devices[bevent->disk];
640                         device->read_only =
641                                 bevent->flags & vioblockflags_ro;
642                         device->size = data->disk_size;
643                         device->cylinders = data->cylinders;
644                         device->tracks = data->tracks;
645                         device->sectors = data->sectors;
646                         device->bytes_per_sector = data->bytes_per_sector;
647                         pwe->max_disk = data->max_disk;
648                 }
649                 complete(&pwe->com);
650                 break;
651         case vioblockclose:
652                 break;
653         case vioblockread:
654         case vioblockwrite:
655                 viodasd_handle_read_write(bevent);
656                 break;
657
658         default:
659                 pr_warning("invalid subtype!");
660                 if (hvlpevent_need_ack(event)) {
661                         event->xRc = HvLpEvent_Rc_InvalidSubtype;
662                         HvCallEvent_ackLpEvent(event);
663                 }
664         }
665 }
666
667 /*
668  * Get the driver to reprobe for more disks.
669  */
670 static ssize_t probe_disks(struct device_driver *drv, const char *buf,
671                 size_t count)
672 {
673         struct viodasd_device *d;
674
675         for (d = viodasd_devices; d < &viodasd_devices[MAX_DISKNO]; d++) {
676                 if (d->disk == NULL)
677                         probe_disk(d);
678         }
679         return count;
680 }
681 static DRIVER_ATTR(probe, S_IWUSR, NULL, probe_disks);
682
683 static int viodasd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
684 {
685         struct viodasd_device *d = &viodasd_devices[vdev->unit_address];
686
687         d->dev = &vdev->dev;
688         if (!probe_disk(d))
689                 return -ENODEV;
690         return 0;
691 }
692
693 static int viodasd_remove(struct vio_dev *vdev)
694 {
695         struct viodasd_device *d;
696
697         d = &viodasd_devices[vdev->unit_address];
698         if (d->disk) {
699                 del_gendisk(d->disk);
700                 blk_cleanup_queue(d->disk->queue);
701                 put_disk(d->disk);
702                 d->disk = NULL;
703         }
704         d->dev = NULL;
705         return 0;
706 }
707
708 /**
709  * viodasd_device_table: Used by vio.c to match devices that we
710  * support.
711  */
712 static struct vio_device_id viodasd_device_table[] __devinitdata = {
713         { "block", "IBM,iSeries-viodasd" },
714         { "", "" }
715 };
716 MODULE_DEVICE_TABLE(vio, viodasd_device_table);
717
718 static struct vio_driver viodasd_driver = {
719         .id_table = viodasd_device_table,
720         .probe = viodasd_probe,
721         .remove = viodasd_remove,
722         .driver = {
723                 .name = "viodasd",
724                 .owner = THIS_MODULE,
725         }
726 };
727
728 static int need_delete_probe;
729
730 /*
731  * Initialize the whole device driver.  Handle module and non-module
732  * versions
733  */
734 static int __init viodasd_init(void)
735 {
736         int rc;
737
738         if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
739                 rc = -ENODEV;
740                 goto early_fail;
741         }
742
743         /* Try to open to our host lp */
744         if (viopath_hostLp == HvLpIndexInvalid)
745                 vio_set_hostlp();
746
747         if (viopath_hostLp == HvLpIndexInvalid) {
748                 pr_warning("invalid hosting partition\n");
749                 rc = -EIO;
750                 goto early_fail;
751         }
752
753         pr_info("vers " VIOD_VERS ", hosting partition %d\n", viopath_hostLp);
754
755         /* register the block device */
756         rc =  register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
757         if (rc) {
758                 pr_warning("Unable to get major number %d for %s\n",
759                            VIODASD_MAJOR, VIOD_GENHD_NAME);
760                 goto early_fail;
761         }
762         /* Actually open the path to the hosting partition */
763         rc = viopath_open(viopath_hostLp, viomajorsubtype_blockio,
764                                 VIOMAXREQ + 2);
765         if (rc) {
766                 pr_warning("error opening path to host partition %d\n",
767                            viopath_hostLp);
768                 goto unregister_blk;
769         }
770
771         /* Initialize our request handler */
772         vio_setHandler(viomajorsubtype_blockio, handle_block_event);
773
774         rc = vio_register_driver(&viodasd_driver);
775         if (rc) {
776                 pr_warning("vio_register_driver failed\n");
777                 goto unset_handler;
778         }
779
780         /*
781          * If this call fails, it just means that we cannot dynamically
782          * add virtual disks, but the driver will still work fine for
783          * all existing disk, so ignore the failure.
784          */
785         if (!driver_create_file(&viodasd_driver.driver, &driver_attr_probe))
786                 need_delete_probe = 1;
787
788         return 0;
789
790 unset_handler:
791         vio_clearHandler(viomajorsubtype_blockio);
792         viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
793 unregister_blk:
794         unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
795 early_fail:
796         return rc;
797 }
798 module_init(viodasd_init);
799
800 void __exit viodasd_exit(void)
801 {
802         if (need_delete_probe)
803                 driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
804         vio_unregister_driver(&viodasd_driver);
805         vio_clearHandler(viomajorsubtype_blockio);
806         viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
807         unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
808 }
809 module_exit(viodasd_exit);