blob: 9e61fca46117e618677483aa74c2ac90c310352c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- 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 <sfr@au1.ibm.com>
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#include <linux/major.h>
32#include <linux/fs.h>
33#include <linux/module.h>
34#include <linux/kernel.h>
35#include <linux/blkdev.h>
36#include <linux/genhd.h>
37#include <linux/hdreg.h>
38#include <linux/errno.h>
39#include <linux/init.h>
40#include <linux/string.h>
41#include <linux/dma-mapping.h>
42#include <linux/completion.h>
43#include <linux/device.h>
Jens Axboe45711f12007-10-22 21:19:53 +020044#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46#include <asm/uaccess.h>
47#include <asm/vio.h>
Kelly Daly1ec65d72005-11-02 13:46:07 +110048#include <asm/iseries/hv_types.h>
Kelly Dalye45423e2005-11-02 12:08:31 +110049#include <asm/iseries/hv_lp_event.h>
Kelly Daly15b17182005-11-02 11:55:28 +110050#include <asm/iseries/hv_lp_config.h>
Kelly Dalyb4206772005-11-02 15:13:57 +110051#include <asm/iseries/vio.h>
Stephen Rothwellfb8b5002006-12-15 15:40:08 +110052#include <asm/firmware.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54MODULE_DESCRIPTION("iSeries Virtual DASD");
55MODULE_AUTHOR("Dave Boutcher");
56MODULE_LICENSE("GPL");
57
58/*
59 * We only support 7 partitions per physical disk....so with minor
60 * numbers 0-255 we get a maximum of 32 disks.
61 */
62#define VIOD_GENHD_NAME "iseries/vd"
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
64#define VIOD_VERS "1.64"
65
66#define VIOD_KERN_WARNING KERN_WARNING "viod: "
67#define VIOD_KERN_INFO KERN_INFO "viod: "
68
69enum {
70 PARTITION_SHIFT = 3,
71 MAX_DISKNO = HVMAXARCHITECTEDVIRTUALDISKS,
72 MAX_DISK_NAME = sizeof(((struct gendisk *)0)->disk_name)
73};
74
75static DEFINE_SPINLOCK(viodasd_spinlock);
76
77#define VIOMAXREQ 16
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79#define DEVICE_NO(cell) ((struct viodasd_device *)(cell) - &viodasd_devices[0])
80
Linus Torvalds1da177e2005-04-16 15:20:36 -070081struct viodasd_waitevent {
82 struct completion com;
83 int rc;
84 u16 sub_result;
85 int max_disk; /* open */
86};
87
88static const struct vio_error_entry viodasd_err_table[] = {
89 { 0x0201, EINVAL, "Invalid Range" },
90 { 0x0202, EINVAL, "Invalid Token" },
91 { 0x0203, EIO, "DMA Error" },
92 { 0x0204, EIO, "Use Error" },
93 { 0x0205, EIO, "Release Error" },
94 { 0x0206, EINVAL, "Invalid Disk" },
95 { 0x0207, EBUSY, "Cant Lock" },
96 { 0x0208, EIO, "Already Locked" },
97 { 0x0209, EIO, "Already Unlocked" },
98 { 0x020A, EIO, "Invalid Arg" },
99 { 0x020B, EIO, "Bad IFS File" },
100 { 0x020C, EROFS, "Read Only Device" },
101 { 0x02FF, EIO, "Internal Error" },
102 { 0x0000, 0, NULL },
103};
104
105/*
106 * Figure out the biggest I/O request (in sectors) we can accept
107 */
108#define VIODASD_MAXSECTORS (4096 / 512 * VIOMAXBLOCKDMA)
109
110/*
111 * Number of disk I/O requests we've sent to OS/400
112 */
113static int num_req_outstanding;
114
115/*
116 * This is our internal structure for keeping track of disk devices
117 */
118struct viodasd_device {
119 u16 cylinders;
120 u16 tracks;
121 u16 sectors;
122 u16 bytes_per_sector;
123 u64 size;
124 int read_only;
125 spinlock_t q_lock;
126 struct gendisk *disk;
127 struct device *dev;
128} viodasd_devices[MAX_DISKNO];
129
130/*
131 * External open entry point.
132 */
133static int viodasd_open(struct inode *ino, struct file *fil)
134{
135 struct viodasd_device *d = ino->i_bdev->bd_disk->private_data;
136 HvLpEvent_Rc hvrc;
137 struct viodasd_waitevent we;
138 u16 flags = 0;
139
140 if (d->read_only) {
141 if ((fil != NULL) && (fil->f_mode & FMODE_WRITE))
142 return -EROFS;
143 flags = vioblockflags_ro;
144 }
145
146 init_completion(&we.com);
147
148 /* Send the open event to OS/400 */
149 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
150 HvLpEvent_Type_VirtualIo,
151 viomajorsubtype_blockio | vioblockopen,
152 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
153 viopath_sourceinst(viopath_hostLp),
154 viopath_targetinst(viopath_hostLp),
155 (u64)(unsigned long)&we, VIOVERSION << 16,
156 ((u64)DEVICE_NO(d) << 48) | ((u64)flags << 32),
157 0, 0, 0);
158 if (hvrc != 0) {
159 printk(VIOD_KERN_WARNING "HV open failed %d\n", (int)hvrc);
160 return -EIO;
161 }
162
163 wait_for_completion(&we.com);
164
165 /* Check the return code */
166 if (we.rc != 0) {
167 const struct vio_error_entry *err =
168 vio_lookup_rc(viodasd_err_table, we.sub_result);
169
170 printk(VIOD_KERN_WARNING
171 "bad rc opening disk: %d:0x%04x (%s)\n",
172 (int)we.rc, we.sub_result, err->msg);
173 return -EIO;
174 }
175
176 return 0;
177}
178
179/*
180 * External release entry point.
181 */
182static int viodasd_release(struct inode *ino, struct file *fil)
183{
184 struct viodasd_device *d = ino->i_bdev->bd_disk->private_data;
185 HvLpEvent_Rc hvrc;
186
187 /* Send the event to OS/400. We DON'T expect a response */
188 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
189 HvLpEvent_Type_VirtualIo,
190 viomajorsubtype_blockio | vioblockclose,
191 HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
192 viopath_sourceinst(viopath_hostLp),
193 viopath_targetinst(viopath_hostLp),
194 0, VIOVERSION << 16,
195 ((u64)DEVICE_NO(d) << 48) /* | ((u64)flags << 32) */,
196 0, 0, 0);
197 if (hvrc != 0)
198 printk(VIOD_KERN_WARNING "HV close call failed %d\n",
199 (int)hvrc);
200 return 0;
201}
202
203
204/* External ioctl entry point.
205 */
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800206static int viodasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207{
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800208 struct gendisk *disk = bdev->bd_disk;
209 struct viodasd_device *d = disk->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
Stephen Rothwell36a70032007-05-29 16:06:54 +1000211 geo->sectors = d->sectors ? d->sectors : 32;
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800212 geo->heads = d->tracks ? d->tracks : 64;
213 geo->cylinders = d->cylinders ? d->cylinders :
Stephen Rothwell36a70032007-05-29 16:06:54 +1000214 get_capacity(disk) / (geo->sectors * geo->heads);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800216 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217}
218
219/*
220 * Our file operations table
221 */
222static struct block_device_operations viodasd_fops = {
223 .owner = THIS_MODULE,
224 .open = viodasd_open,
225 .release = viodasd_release,
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800226 .getgeo = viodasd_getgeo,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227};
228
229/*
230 * End a request
231 */
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500232static void viodasd_end_request(struct request *req, int error,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 int num_sectors)
234{
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500235 __blk_end_request(req, error, num_sectors << 9);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
238/*
239 * Send an actual I/O request to OS/400
240 */
241static int send_request(struct request *req)
242{
243 u64 start;
244 int direction;
245 int nsg;
246 u16 viocmd;
247 HvLpEvent_Rc hvrc;
248 struct vioblocklpevent *bevent;
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100249 struct HvLpEvent *hev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 struct scatterlist sg[VIOMAXBLOCKDMA];
251 int sgindex;
252 int statindex;
253 struct viodasd_device *d;
254 unsigned long flags;
255
256 start = (u64)req->sector << 9;
257
258 if (rq_data_dir(req) == READ) {
259 direction = DMA_FROM_DEVICE;
260 viocmd = viomajorsubtype_blockio | vioblockread;
261 statindex = 0;
262 } else {
263 direction = DMA_TO_DEVICE;
264 viocmd = viomajorsubtype_blockio | vioblockwrite;
265 statindex = 1;
266 }
267
268 d = req->rq_disk->private_data;
269
270 /* Now build the scatter-gather list */
Jens Axboe45711f12007-10-22 21:19:53 +0200271 sg_init_table(sg, VIOMAXBLOCKDMA);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 nsg = blk_rq_map_sg(req->q, req, sg);
273 nsg = dma_map_sg(d->dev, sg, nsg, direction);
274
275 spin_lock_irqsave(&viodasd_spinlock, flags);
276 num_req_outstanding++;
277
278 /* This optimization handles a single DMA block */
279 if (nsg == 1)
280 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
281 HvLpEvent_Type_VirtualIo, viocmd,
282 HvLpEvent_AckInd_DoAck,
283 HvLpEvent_AckType_ImmediateAck,
284 viopath_sourceinst(viopath_hostLp),
285 viopath_targetinst(viopath_hostLp),
286 (u64)(unsigned long)req, VIOVERSION << 16,
287 ((u64)DEVICE_NO(d) << 48), start,
288 ((u64)sg_dma_address(&sg[0])) << 32,
289 sg_dma_len(&sg[0]));
290 else {
291 bevent = (struct vioblocklpevent *)
292 vio_get_event_buffer(viomajorsubtype_blockio);
293 if (bevent == NULL) {
294 printk(VIOD_KERN_WARNING
295 "error allocating disk event buffer\n");
296 goto error_ret;
297 }
298
299 /*
300 * Now build up the actual request. Note that we store
301 * the pointer to the request in the correlation
302 * token so we can match the response up later
303 */
304 memset(bevent, 0, sizeof(struct vioblocklpevent));
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100305 hev = &bevent->event;
306 hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DO_ACK |
307 HV_LP_EVENT_INT;
308 hev->xType = HvLpEvent_Type_VirtualIo;
309 hev->xSubtype = viocmd;
310 hev->xSourceLp = HvLpConfig_getLpIndex();
311 hev->xTargetLp = viopath_hostLp;
312 hev->xSizeMinus1 =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 offsetof(struct vioblocklpevent, u.rw_data.dma_info) +
314 (sizeof(bevent->u.rw_data.dma_info[0]) * nsg) - 1;
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100315 hev->xSourceInstanceId = viopath_sourceinst(viopath_hostLp);
316 hev->xTargetInstanceId = viopath_targetinst(viopath_hostLp);
317 hev->xCorrelationToken = (u64)req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 bevent->version = VIOVERSION;
319 bevent->disk = DEVICE_NO(d);
320 bevent->u.rw_data.offset = start;
321
322 /*
323 * Copy just the dma information from the sg list
324 * into the request
325 */
326 for (sgindex = 0; sgindex < nsg; sgindex++) {
327 bevent->u.rw_data.dma_info[sgindex].token =
328 sg_dma_address(&sg[sgindex]);
329 bevent->u.rw_data.dma_info[sgindex].len =
330 sg_dma_len(&sg[sgindex]);
331 }
332
333 /* Send the request */
334 hvrc = HvCallEvent_signalLpEvent(&bevent->event);
335 vio_free_event_buffer(viomajorsubtype_blockio, bevent);
336 }
337
338 if (hvrc != HvLpEvent_Rc_Good) {
339 printk(VIOD_KERN_WARNING
340 "error sending disk event to OS/400 (rc %d)\n",
341 (int)hvrc);
342 goto error_ret;
343 }
344 spin_unlock_irqrestore(&viodasd_spinlock, flags);
345 return 0;
346
347error_ret:
348 num_req_outstanding--;
349 spin_unlock_irqrestore(&viodasd_spinlock, flags);
350 dma_unmap_sg(d->dev, sg, nsg, direction);
351 return -1;
352}
353
354/*
355 * This is the external request processing routine
356 */
Jens Axboe165125e2007-07-24 09:28:11 +0200357static void do_viodasd_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
359 struct request *req;
360
361 /*
362 * If we already have the maximum number of requests
363 * outstanding to OS/400 just bail out. We'll come
364 * back later.
365 */
366 while (num_req_outstanding < VIOMAXREQ) {
367 req = elv_next_request(q);
368 if (req == NULL)
369 return;
370 /* dequeue the current request from the queue */
371 blkdev_dequeue_request(req);
372 /* check that request contains a valid command */
373 if (!blk_fs_request(req)) {
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500374 viodasd_end_request(req, -EIO, req->hard_nr_sectors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 continue;
376 }
377 /* Try sending the request */
378 if (send_request(req) != 0)
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500379 viodasd_end_request(req, -EIO, req->hard_nr_sectors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 }
381}
382
383/*
384 * Probe a single disk and fill in the viodasd_device structure
385 * for it.
386 */
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000387static int probe_disk(struct viodasd_device *d)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
389 HvLpEvent_Rc hvrc;
390 struct viodasd_waitevent we;
391 int dev_no = DEVICE_NO(d);
392 struct gendisk *g;
393 struct request_queue *q;
394 u16 flags = 0;
395
396retry:
397 init_completion(&we.com);
398
399 /* Send the open event to OS/400 */
400 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
401 HvLpEvent_Type_VirtualIo,
402 viomajorsubtype_blockio | vioblockopen,
403 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
404 viopath_sourceinst(viopath_hostLp),
405 viopath_targetinst(viopath_hostLp),
406 (u64)(unsigned long)&we, VIOVERSION << 16,
407 ((u64)dev_no << 48) | ((u64)flags<< 32),
408 0, 0, 0);
409 if (hvrc != 0) {
410 printk(VIOD_KERN_WARNING "bad rc on HV open %d\n", (int)hvrc);
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000411 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 }
413
414 wait_for_completion(&we.com);
415
416 if (we.rc != 0) {
417 if (flags != 0)
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000418 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 /* try again with read only flag set */
420 flags = vioblockflags_ro;
421 goto retry;
422 }
423 if (we.max_disk > (MAX_DISKNO - 1)) {
424 static int warned;
425
426 if (warned == 0) {
427 warned++;
428 printk(VIOD_KERN_INFO
429 "Only examining the first %d "
430 "of %d disks connected\n",
431 MAX_DISKNO, we.max_disk + 1);
432 }
433 }
434
435 /* Send the close event to OS/400. We DON'T expect a response */
436 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
437 HvLpEvent_Type_VirtualIo,
438 viomajorsubtype_blockio | vioblockclose,
439 HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
440 viopath_sourceinst(viopath_hostLp),
441 viopath_targetinst(viopath_hostLp),
442 0, VIOVERSION << 16,
443 ((u64)dev_no << 48) | ((u64)flags << 32),
444 0, 0, 0);
445 if (hvrc != 0) {
446 printk(VIOD_KERN_WARNING
447 "bad rc sending event to OS/400 %d\n", (int)hvrc);
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000448 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 }
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000450
451 if (d->dev == NULL) {
452 /* this is when we reprobe for new disks */
453 if (vio_create_viodasd(dev_no) == NULL) {
454 printk(VIOD_KERN_WARNING
455 "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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 /* 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 printk(VIOD_KERN_WARNING "cannot allocate queue for disk %d\n",
472 dev_no);
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000473 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 }
475 g = alloc_disk(1 << PARTITION_SHIFT);
476 if (g == NULL) {
477 printk(VIOD_KERN_WARNING
478 "cannot allocate disk structure for disk %d\n",
479 dev_no);
480 blk_cleanup_queue(q);
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000481 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 }
483
484 d->disk = g;
485 blk_queue_max_hw_segments(q, VIOMAXBLOCKDMA);
486 blk_queue_max_phys_segments(q, VIOMAXBLOCKDMA);
487 blk_queue_max_sectors(q, VIODASD_MAXSECTORS);
488 g->major = VIODASD_MAJOR;
489 g->first_minor = dev_no << PARTITION_SHIFT;
490 if (dev_no >= 26)
491 snprintf(g->disk_name, sizeof(g->disk_name),
492 VIOD_GENHD_NAME "%c%c",
493 'a' + (dev_no / 26) - 1, 'a' + (dev_no % 26));
494 else
495 snprintf(g->disk_name, sizeof(g->disk_name),
496 VIOD_GENHD_NAME "%c", 'a' + (dev_no % 26));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 g->fops = &viodasd_fops;
498 g->queue = q;
499 g->private_data = d;
500 g->driverfs_dev = d->dev;
501 set_capacity(g, d->size >> 9);
502
503 printk(VIOD_KERN_INFO "disk %d: %lu sectors (%lu MB) "
504 "CHS=%d/%d/%d sector size %d%s\n",
505 dev_no, (unsigned long)(d->size >> 9),
506 (unsigned long)(d->size >> 20),
507 (int)d->cylinders, (int)d->tracks,
508 (int)d->sectors, (int)d->bytes_per_sector,
509 d->read_only ? " (RO)" : "");
510
511 /* register us in the global list */
512 add_disk(g);
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000513 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514}
515
516/* returns the total number of scatterlist elements converted */
517static int block_event_to_scatterlist(const struct vioblocklpevent *bevent,
518 struct scatterlist *sg, int *total_len)
519{
520 int i, numsg;
521 const struct rw_data *rw_data = &bevent->u.rw_data;
522 static const int offset =
523 offsetof(struct vioblocklpevent, u.rw_data.dma_info);
524 static const int element_size = sizeof(rw_data->dma_info[0]);
525
526 numsg = ((bevent->event.xSizeMinus1 + 1) - offset) / element_size;
527 if (numsg > VIOMAXBLOCKDMA)
528 numsg = VIOMAXBLOCKDMA;
529
530 *total_len = 0;
531 memset(sg, 0, sizeof(sg[0]) * VIOMAXBLOCKDMA);
532
533 for (i = 0; (i < numsg) && (rw_data->dma_info[i].len > 0); ++i) {
534 sg_dma_address(&sg[i]) = rw_data->dma_info[i].token;
535 sg_dma_len(&sg[i]) = rw_data->dma_info[i].len;
536 *total_len += rw_data->dma_info[i].len;
537 }
538 return i;
539}
540
541/*
542 * Restart all queues, starting with the one _after_ the disk given,
543 * thus reducing the chance of starvation of higher numbered disks.
544 */
545static void viodasd_restart_all_queues_starting_from(int first_index)
546{
547 int i;
548
549 for (i = first_index + 1; i < MAX_DISKNO; ++i)
550 if (viodasd_devices[i].disk)
551 blk_run_queue(viodasd_devices[i].disk->queue);
552 for (i = 0; i <= first_index; ++i)
553 if (viodasd_devices[i].disk)
554 blk_run_queue(viodasd_devices[i].disk->queue);
555}
556
557/*
558 * For read and write requests, decrement the number of outstanding requests,
559 * Free the DMA buffers we allocated.
560 */
561static int viodasd_handle_read_write(struct vioblocklpevent *bevent)
562{
563 int num_sg, num_sect, pci_direction, total_len;
564 struct request *req;
565 struct scatterlist sg[VIOMAXBLOCKDMA];
566 struct HvLpEvent *event = &bevent->event;
567 unsigned long irq_flags;
568 struct viodasd_device *d;
569 int error;
570 spinlock_t *qlock;
571
572 num_sg = block_event_to_scatterlist(bevent, sg, &total_len);
573 num_sect = total_len >> 9;
574 if (event->xSubtype == (viomajorsubtype_blockio | vioblockread))
575 pci_direction = DMA_FROM_DEVICE;
576 else
577 pci_direction = DMA_TO_DEVICE;
578 req = (struct request *)bevent->event.xCorrelationToken;
579 d = req->rq_disk->private_data;
580
581 dma_unmap_sg(d->dev, sg, num_sg, pci_direction);
582
583 /*
584 * Since this is running in interrupt mode, we need to make sure
585 * we're not stepping on any global I/O operations
586 */
587 spin_lock_irqsave(&viodasd_spinlock, irq_flags);
588 num_req_outstanding--;
589 spin_unlock_irqrestore(&viodasd_spinlock, irq_flags);
590
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500591 error = (event->xRc == HvLpEvent_Rc_Good) ? 0 : -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 if (error) {
593 const struct vio_error_entry *err;
594 err = vio_lookup_rc(viodasd_err_table, bevent->sub_result);
595 printk(VIOD_KERN_WARNING "read/write error %d:0x%04x (%s)\n",
596 event->xRc, bevent->sub_result, err->msg);
597 num_sect = req->hard_nr_sectors;
598 }
599 qlock = req->q->queue_lock;
600 spin_lock_irqsave(qlock, irq_flags);
Kiyoshi Uedab2aec242007-12-11 17:47:14 -0500601 viodasd_end_request(req, error, num_sect);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 spin_unlock_irqrestore(qlock, irq_flags);
603
604 /* Finally, try to get more requests off of this device's queue */
605 viodasd_restart_all_queues_starting_from(DEVICE_NO(d));
606
607 return 0;
608}
609
610/* This routine handles incoming block LP events */
611static void handle_block_event(struct HvLpEvent *event)
612{
613 struct vioblocklpevent *bevent = (struct vioblocklpevent *)event;
614 struct viodasd_waitevent *pwe;
615
616 if (event == NULL)
617 /* Notification that a partition went away! */
618 return;
619 /* First, we should NEVER get an int here...only acks */
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100620 if (hvlpevent_is_int(event)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 printk(VIOD_KERN_WARNING
622 "Yikes! got an int in viodasd event handler!\n");
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100623 if (hvlpevent_need_ack(event)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 event->xRc = HvLpEvent_Rc_InvalidSubtype;
625 HvCallEvent_ackLpEvent(event);
626 }
627 }
628
629 switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) {
630 case vioblockopen:
631 /*
632 * Handle a response to an open request. We get all the
633 * disk information in the response, so update it. The
634 * correlation token contains a pointer to a waitevent
635 * structure that has a completion in it. update the
636 * return code in the waitevent structure and post the
637 * completion to wake up the guy who sent the request
638 */
639 pwe = (struct viodasd_waitevent *)event->xCorrelationToken;
640 pwe->rc = event->xRc;
641 pwe->sub_result = bevent->sub_result;
642 if (event->xRc == HvLpEvent_Rc_Good) {
643 const struct open_data *data = &bevent->u.open_data;
644 struct viodasd_device *device =
645 &viodasd_devices[bevent->disk];
646 device->read_only =
647 bevent->flags & vioblockflags_ro;
648 device->size = data->disk_size;
649 device->cylinders = data->cylinders;
650 device->tracks = data->tracks;
651 device->sectors = data->sectors;
652 device->bytes_per_sector = data->bytes_per_sector;
653 pwe->max_disk = data->max_disk;
654 }
655 complete(&pwe->com);
656 break;
657 case vioblockclose:
658 break;
659 case vioblockread:
660 case vioblockwrite:
661 viodasd_handle_read_write(bevent);
662 break;
663
664 default:
665 printk(VIOD_KERN_WARNING "invalid subtype!");
Stephen Rothwell677f8c02006-01-12 13:47:43 +1100666 if (hvlpevent_need_ack(event)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 event->xRc = HvLpEvent_Rc_InvalidSubtype;
668 HvCallEvent_ackLpEvent(event);
669 }
670 }
671}
672
673/*
674 * Get the driver to reprobe for more disks.
675 */
676static ssize_t probe_disks(struct device_driver *drv, const char *buf,
677 size_t count)
678{
679 struct viodasd_device *d;
680
681 for (d = viodasd_devices; d < &viodasd_devices[MAX_DISKNO]; d++) {
682 if (d->disk == NULL)
683 probe_disk(d);
684 }
685 return count;
686}
687static DRIVER_ATTR(probe, S_IWUSR, NULL, probe_disks);
688
689static int viodasd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
690{
691 struct viodasd_device *d = &viodasd_devices[vdev->unit_address];
692
693 d->dev = &vdev->dev;
Stephen Rothwell8251b4c2007-10-11 14:59:54 +1000694 if (!probe_disk(d))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 return -ENODEV;
696 return 0;
697}
698
699static int viodasd_remove(struct vio_dev *vdev)
700{
701 struct viodasd_device *d;
702
703 d = &viodasd_devices[vdev->unit_address];
704 if (d->disk) {
705 del_gendisk(d->disk);
706 blk_cleanup_queue(d->disk->queue);
707 put_disk(d->disk);
708 d->disk = NULL;
709 }
710 d->dev = NULL;
711 return 0;
712}
713
714/**
715 * viodasd_device_table: Used by vio.c to match devices that we
716 * support.
717 */
718static struct vio_device_id viodasd_device_table[] __devinitdata = {
Stephen Rothwellfbabeb62006-05-15 13:41:22 +1000719 { "block", "IBM,iSeries-viodasd" },
Stephen Rothwellfb120da2005-08-17 16:42:59 +1000720 { "", "" }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722MODULE_DEVICE_TABLE(vio, viodasd_device_table);
Stephen Rothwell915124d2005-10-24 15:12:22 +1000723
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724static struct vio_driver viodasd_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 .id_table = viodasd_device_table,
726 .probe = viodasd_probe,
Stephen Rothwell6fdf5392005-10-24 14:53:21 +1000727 .remove = viodasd_remove,
728 .driver = {
729 .name = "viodasd",
Stephen Rothwell915124d2005-10-24 15:12:22 +1000730 .owner = THIS_MODULE,
Stephen Rothwell6fdf5392005-10-24 14:53:21 +1000731 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732};
733
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100734static int need_delete_probe;
735
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736/*
737 * Initialize the whole device driver. Handle module and non-module
738 * versions
739 */
740static int __init viodasd_init(void)
741{
742 int rc;
743
Stephen Rothwellfb8b5002006-12-15 15:40:08 +1100744 if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
745 rc = -ENODEV;
746 goto early_fail;
747 }
748
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749 /* Try to open to our host lp */
750 if (viopath_hostLp == HvLpIndexInvalid)
751 vio_set_hostlp();
752
753 if (viopath_hostLp == HvLpIndexInvalid) {
754 printk(VIOD_KERN_WARNING "invalid hosting partition\n");
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100755 rc = -EIO;
756 goto early_fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 }
758
759 printk(VIOD_KERN_INFO "vers " VIOD_VERS ", hosting partition %d\n",
760 viopath_hostLp);
761
762 /* register the block device */
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100763 rc = register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
764 if (rc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 printk(VIOD_KERN_WARNING
766 "Unable to get major number %d for %s\n",
767 VIODASD_MAJOR, VIOD_GENHD_NAME);
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100768 goto early_fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 }
770 /* Actually open the path to the hosting partition */
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100771 rc = viopath_open(viopath_hostLp, viomajorsubtype_blockio,
772 VIOMAXREQ + 2);
773 if (rc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774 printk(VIOD_KERN_WARNING
775 "error opening path to host partition %d\n",
776 viopath_hostLp);
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100777 goto unregister_blk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 }
779
780 /* Initialize our request handler */
781 vio_setHandler(viomajorsubtype_blockio, handle_block_event);
782
783 rc = vio_register_driver(&viodasd_driver);
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100784 if (rc) {
785 printk(VIOD_KERN_WARNING "vio_register_driver failed\n");
786 goto unset_handler;
787 }
788
789 /*
790 * If this call fails, it just means that we cannot dynamically
791 * add virtual disks, but the driver will still work fine for
792 * all existing disk, so ignore the failure.
793 */
794 if (!driver_create_file(&viodasd_driver.driver, &driver_attr_probe))
795 need_delete_probe = 1;
796
797 return 0;
798
799unset_handler:
800 vio_clearHandler(viomajorsubtype_blockio);
801 viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
802unregister_blk:
803 unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
804early_fail:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 return rc;
806}
807module_init(viodasd_init);
808
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100809void __exit viodasd_exit(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810{
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100811 if (need_delete_probe)
812 driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 vio_unregister_driver(&viodasd_driver);
814 vio_clearHandler(viomajorsubtype_blockio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815 viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
Stephen Rothwellf9df68e2006-11-13 14:43:17 +1100816 unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818module_exit(viodasd_exit);