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1da177e4 LT |
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 <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> | |
44 | #include <linux/kernel.h> | |
45 | ||
46 | #include <asm/uaccess.h> | |
47 | #include <asm/vio.h> | |
1ec65d76 | 48 | #include <asm/iseries/hv_types.h> |
e45423ea | 49 | #include <asm/iseries/hv_lp_event.h> |
15b17189 | 50 | #include <asm/iseries/hv_lp_config.h> |
b4206778 | 51 | #include <asm/iseries/vio.h> |
1da177e4 LT |
52 | |
53 | MODULE_DESCRIPTION("iSeries Virtual DASD"); | |
54 | MODULE_AUTHOR("Dave Boutcher"); | |
55 | MODULE_LICENSE("GPL"); | |
56 | ||
57 | /* | |
58 | * We only support 7 partitions per physical disk....so with minor | |
59 | * numbers 0-255 we get a maximum of 32 disks. | |
60 | */ | |
61 | #define VIOD_GENHD_NAME "iseries/vd" | |
62 | #define VIOD_GENHD_DEVFS_NAME "iseries/disc" | |
63 | ||
64 | #define VIOD_VERS "1.64" | |
65 | ||
66 | #define VIOD_KERN_WARNING KERN_WARNING "viod: " | |
67 | #define VIOD_KERN_INFO KERN_INFO "viod: " | |
68 | ||
69 | enum { | |
70 | PARTITION_SHIFT = 3, | |
71 | MAX_DISKNO = HVMAXARCHITECTEDVIRTUALDISKS, | |
72 | MAX_DISK_NAME = sizeof(((struct gendisk *)0)->disk_name) | |
73 | }; | |
74 | ||
75 | static DEFINE_SPINLOCK(viodasd_spinlock); | |
76 | ||
77 | #define VIOMAXREQ 16 | |
78 | #define VIOMAXBLOCKDMA 12 | |
79 | ||
80 | #define DEVICE_NO(cell) ((struct viodasd_device *)(cell) - &viodasd_devices[0]) | |
81 | ||
82 | struct open_data { | |
83 | u64 disk_size; | |
84 | u16 max_disk; | |
85 | u16 cylinders; | |
86 | u16 tracks; | |
87 | u16 sectors; | |
88 | u16 bytes_per_sector; | |
89 | }; | |
90 | ||
91 | struct rw_data { | |
92 | u64 offset; | |
93 | struct { | |
94 | u32 token; | |
95 | u32 reserved; | |
96 | u64 len; | |
97 | } dma_info[VIOMAXBLOCKDMA]; | |
98 | }; | |
99 | ||
100 | struct vioblocklpevent { | |
101 | struct HvLpEvent event; | |
102 | u32 reserved; | |
103 | u16 version; | |
104 | u16 sub_result; | |
105 | u16 disk; | |
106 | u16 flags; | |
107 | union { | |
108 | struct open_data open_data; | |
109 | struct rw_data rw_data; | |
110 | u64 changed; | |
111 | } u; | |
112 | }; | |
113 | ||
114 | #define vioblockflags_ro 0x0001 | |
115 | ||
116 | enum vioblocksubtype { | |
117 | vioblockopen = 0x0001, | |
118 | vioblockclose = 0x0002, | |
119 | vioblockread = 0x0003, | |
120 | vioblockwrite = 0x0004, | |
121 | vioblockflush = 0x0005, | |
122 | vioblockcheck = 0x0007 | |
123 | }; | |
124 | ||
125 | struct viodasd_waitevent { | |
126 | struct completion com; | |
127 | int rc; | |
128 | u16 sub_result; | |
129 | int max_disk; /* open */ | |
130 | }; | |
131 | ||
132 | static const struct vio_error_entry viodasd_err_table[] = { | |
133 | { 0x0201, EINVAL, "Invalid Range" }, | |
134 | { 0x0202, EINVAL, "Invalid Token" }, | |
135 | { 0x0203, EIO, "DMA Error" }, | |
136 | { 0x0204, EIO, "Use Error" }, | |
137 | { 0x0205, EIO, "Release Error" }, | |
138 | { 0x0206, EINVAL, "Invalid Disk" }, | |
139 | { 0x0207, EBUSY, "Cant Lock" }, | |
140 | { 0x0208, EIO, "Already Locked" }, | |
141 | { 0x0209, EIO, "Already Unlocked" }, | |
142 | { 0x020A, EIO, "Invalid Arg" }, | |
143 | { 0x020B, EIO, "Bad IFS File" }, | |
144 | { 0x020C, EROFS, "Read Only Device" }, | |
145 | { 0x02FF, EIO, "Internal Error" }, | |
146 | { 0x0000, 0, NULL }, | |
147 | }; | |
148 | ||
149 | /* | |
150 | * Figure out the biggest I/O request (in sectors) we can accept | |
151 | */ | |
152 | #define VIODASD_MAXSECTORS (4096 / 512 * VIOMAXBLOCKDMA) | |
153 | ||
154 | /* | |
155 | * Number of disk I/O requests we've sent to OS/400 | |
156 | */ | |
157 | static int num_req_outstanding; | |
158 | ||
159 | /* | |
160 | * This is our internal structure for keeping track of disk devices | |
161 | */ | |
162 | struct viodasd_device { | |
163 | u16 cylinders; | |
164 | u16 tracks; | |
165 | u16 sectors; | |
166 | u16 bytes_per_sector; | |
167 | u64 size; | |
168 | int read_only; | |
169 | spinlock_t q_lock; | |
170 | struct gendisk *disk; | |
171 | struct device *dev; | |
172 | } viodasd_devices[MAX_DISKNO]; | |
173 | ||
174 | /* | |
175 | * External open entry point. | |
176 | */ | |
177 | static int viodasd_open(struct inode *ino, struct file *fil) | |
178 | { | |
179 | struct viodasd_device *d = ino->i_bdev->bd_disk->private_data; | |
180 | HvLpEvent_Rc hvrc; | |
181 | struct viodasd_waitevent we; | |
182 | u16 flags = 0; | |
183 | ||
184 | if (d->read_only) { | |
185 | if ((fil != NULL) && (fil->f_mode & FMODE_WRITE)) | |
186 | return -EROFS; | |
187 | flags = vioblockflags_ro; | |
188 | } | |
189 | ||
190 | init_completion(&we.com); | |
191 | ||
192 | /* Send the open event to OS/400 */ | |
193 | hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp, | |
194 | HvLpEvent_Type_VirtualIo, | |
195 | viomajorsubtype_blockio | vioblockopen, | |
196 | HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck, | |
197 | viopath_sourceinst(viopath_hostLp), | |
198 | viopath_targetinst(viopath_hostLp), | |
199 | (u64)(unsigned long)&we, VIOVERSION << 16, | |
200 | ((u64)DEVICE_NO(d) << 48) | ((u64)flags << 32), | |
201 | 0, 0, 0); | |
202 | if (hvrc != 0) { | |
203 | printk(VIOD_KERN_WARNING "HV open failed %d\n", (int)hvrc); | |
204 | return -EIO; | |
205 | } | |
206 | ||
207 | wait_for_completion(&we.com); | |
208 | ||
209 | /* Check the return code */ | |
210 | if (we.rc != 0) { | |
211 | const struct vio_error_entry *err = | |
212 | vio_lookup_rc(viodasd_err_table, we.sub_result); | |
213 | ||
214 | printk(VIOD_KERN_WARNING | |
215 | "bad rc opening disk: %d:0x%04x (%s)\n", | |
216 | (int)we.rc, we.sub_result, err->msg); | |
217 | return -EIO; | |
218 | } | |
219 | ||
220 | return 0; | |
221 | } | |
222 | ||
223 | /* | |
224 | * External release entry point. | |
225 | */ | |
226 | static int viodasd_release(struct inode *ino, struct file *fil) | |
227 | { | |
228 | struct viodasd_device *d = ino->i_bdev->bd_disk->private_data; | |
229 | HvLpEvent_Rc hvrc; | |
230 | ||
231 | /* Send the event to OS/400. We DON'T expect a response */ | |
232 | hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp, | |
233 | HvLpEvent_Type_VirtualIo, | |
234 | viomajorsubtype_blockio | vioblockclose, | |
235 | HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck, | |
236 | viopath_sourceinst(viopath_hostLp), | |
237 | viopath_targetinst(viopath_hostLp), | |
238 | 0, VIOVERSION << 16, | |
239 | ((u64)DEVICE_NO(d) << 48) /* | ((u64)flags << 32) */, | |
240 | 0, 0, 0); | |
241 | if (hvrc != 0) | |
242 | printk(VIOD_KERN_WARNING "HV close call failed %d\n", | |
243 | (int)hvrc); | |
244 | return 0; | |
245 | } | |
246 | ||
247 | ||
248 | /* External ioctl entry point. | |
249 | */ | |
a885c8c4 | 250 | static int viodasd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1da177e4 | 251 | { |
a885c8c4 CH |
252 | struct gendisk *disk = bdev->bd_disk; |
253 | struct viodasd_device *d = disk->private_data; | |
254 | ||
255 | geo->sectors = d->sectors ? d->sectors : 0; | |
256 | geo->heads = d->tracks ? d->tracks : 64; | |
257 | geo->cylinders = d->cylinders ? d->cylinders : | |
258 | get_capacity(disk) / (geo->cylinders * geo->heads); | |
1da177e4 | 259 | |
a885c8c4 | 260 | return 0; |
1da177e4 LT |
261 | } |
262 | ||
263 | /* | |
264 | * Our file operations table | |
265 | */ | |
266 | static struct block_device_operations viodasd_fops = { | |
267 | .owner = THIS_MODULE, | |
268 | .open = viodasd_open, | |
269 | .release = viodasd_release, | |
a885c8c4 | 270 | .getgeo = viodasd_getgeo, |
1da177e4 LT |
271 | }; |
272 | ||
273 | /* | |
274 | * End a request | |
275 | */ | |
276 | static void viodasd_end_request(struct request *req, int uptodate, | |
277 | int num_sectors) | |
278 | { | |
279 | if (end_that_request_first(req, uptodate, num_sectors)) | |
280 | return; | |
281 | add_disk_randomness(req->rq_disk); | |
8ffdc655 | 282 | end_that_request_last(req, uptodate); |
1da177e4 LT |
283 | } |
284 | ||
285 | /* | |
286 | * Send an actual I/O request to OS/400 | |
287 | */ | |
288 | static int send_request(struct request *req) | |
289 | { | |
290 | u64 start; | |
291 | int direction; | |
292 | int nsg; | |
293 | u16 viocmd; | |
294 | HvLpEvent_Rc hvrc; | |
295 | struct vioblocklpevent *bevent; | |
677f8c0d | 296 | struct HvLpEvent *hev; |
1da177e4 LT |
297 | struct scatterlist sg[VIOMAXBLOCKDMA]; |
298 | int sgindex; | |
299 | int statindex; | |
300 | struct viodasd_device *d; | |
301 | unsigned long flags; | |
302 | ||
303 | start = (u64)req->sector << 9; | |
304 | ||
305 | if (rq_data_dir(req) == READ) { | |
306 | direction = DMA_FROM_DEVICE; | |
307 | viocmd = viomajorsubtype_blockio | vioblockread; | |
308 | statindex = 0; | |
309 | } else { | |
310 | direction = DMA_TO_DEVICE; | |
311 | viocmd = viomajorsubtype_blockio | vioblockwrite; | |
312 | statindex = 1; | |
313 | } | |
314 | ||
315 | d = req->rq_disk->private_data; | |
316 | ||
317 | /* Now build the scatter-gather list */ | |
318 | nsg = blk_rq_map_sg(req->q, req, sg); | |
319 | nsg = dma_map_sg(d->dev, sg, nsg, direction); | |
320 | ||
321 | spin_lock_irqsave(&viodasd_spinlock, flags); | |
322 | num_req_outstanding++; | |
323 | ||
324 | /* This optimization handles a single DMA block */ | |
325 | if (nsg == 1) | |
326 | hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp, | |
327 | HvLpEvent_Type_VirtualIo, viocmd, | |
328 | HvLpEvent_AckInd_DoAck, | |
329 | HvLpEvent_AckType_ImmediateAck, | |
330 | viopath_sourceinst(viopath_hostLp), | |
331 | viopath_targetinst(viopath_hostLp), | |
332 | (u64)(unsigned long)req, VIOVERSION << 16, | |
333 | ((u64)DEVICE_NO(d) << 48), start, | |
334 | ((u64)sg_dma_address(&sg[0])) << 32, | |
335 | sg_dma_len(&sg[0])); | |
336 | else { | |
337 | bevent = (struct vioblocklpevent *) | |
338 | vio_get_event_buffer(viomajorsubtype_blockio); | |
339 | if (bevent == NULL) { | |
340 | printk(VIOD_KERN_WARNING | |
341 | "error allocating disk event buffer\n"); | |
342 | goto error_ret; | |
343 | } | |
344 | ||
345 | /* | |
346 | * Now build up the actual request. Note that we store | |
347 | * the pointer to the request in the correlation | |
348 | * token so we can match the response up later | |
349 | */ | |
350 | memset(bevent, 0, sizeof(struct vioblocklpevent)); | |
677f8c0d SR |
351 | hev = &bevent->event; |
352 | hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DO_ACK | | |
353 | HV_LP_EVENT_INT; | |
354 | hev->xType = HvLpEvent_Type_VirtualIo; | |
355 | hev->xSubtype = viocmd; | |
356 | hev->xSourceLp = HvLpConfig_getLpIndex(); | |
357 | hev->xTargetLp = viopath_hostLp; | |
358 | hev->xSizeMinus1 = | |
1da177e4 LT |
359 | offsetof(struct vioblocklpevent, u.rw_data.dma_info) + |
360 | (sizeof(bevent->u.rw_data.dma_info[0]) * nsg) - 1; | |
677f8c0d SR |
361 | hev->xSourceInstanceId = viopath_sourceinst(viopath_hostLp); |
362 | hev->xTargetInstanceId = viopath_targetinst(viopath_hostLp); | |
363 | hev->xCorrelationToken = (u64)req; | |
1da177e4 LT |
364 | bevent->version = VIOVERSION; |
365 | bevent->disk = DEVICE_NO(d); | |
366 | bevent->u.rw_data.offset = start; | |
367 | ||
368 | /* | |
369 | * Copy just the dma information from the sg list | |
370 | * into the request | |
371 | */ | |
372 | for (sgindex = 0; sgindex < nsg; sgindex++) { | |
373 | bevent->u.rw_data.dma_info[sgindex].token = | |
374 | sg_dma_address(&sg[sgindex]); | |
375 | bevent->u.rw_data.dma_info[sgindex].len = | |
376 | sg_dma_len(&sg[sgindex]); | |
377 | } | |
378 | ||
379 | /* Send the request */ | |
380 | hvrc = HvCallEvent_signalLpEvent(&bevent->event); | |
381 | vio_free_event_buffer(viomajorsubtype_blockio, bevent); | |
382 | } | |
383 | ||
384 | if (hvrc != HvLpEvent_Rc_Good) { | |
385 | printk(VIOD_KERN_WARNING | |
386 | "error sending disk event to OS/400 (rc %d)\n", | |
387 | (int)hvrc); | |
388 | goto error_ret; | |
389 | } | |
390 | spin_unlock_irqrestore(&viodasd_spinlock, flags); | |
391 | return 0; | |
392 | ||
393 | error_ret: | |
394 | num_req_outstanding--; | |
395 | spin_unlock_irqrestore(&viodasd_spinlock, flags); | |
396 | dma_unmap_sg(d->dev, sg, nsg, direction); | |
397 | return -1; | |
398 | } | |
399 | ||
400 | /* | |
401 | * This is the external request processing routine | |
402 | */ | |
403 | static void do_viodasd_request(request_queue_t *q) | |
404 | { | |
405 | struct request *req; | |
406 | ||
407 | /* | |
408 | * If we already have the maximum number of requests | |
409 | * outstanding to OS/400 just bail out. We'll come | |
410 | * back later. | |
411 | */ | |
412 | while (num_req_outstanding < VIOMAXREQ) { | |
413 | req = elv_next_request(q); | |
414 | if (req == NULL) | |
415 | return; | |
416 | /* dequeue the current request from the queue */ | |
417 | blkdev_dequeue_request(req); | |
418 | /* check that request contains a valid command */ | |
419 | if (!blk_fs_request(req)) { | |
420 | viodasd_end_request(req, 0, req->hard_nr_sectors); | |
421 | continue; | |
422 | } | |
423 | /* Try sending the request */ | |
424 | if (send_request(req) != 0) | |
425 | viodasd_end_request(req, 0, req->hard_nr_sectors); | |
426 | } | |
427 | } | |
428 | ||
429 | /* | |
430 | * Probe a single disk and fill in the viodasd_device structure | |
431 | * for it. | |
432 | */ | |
433 | static void probe_disk(struct viodasd_device *d) | |
434 | { | |
435 | HvLpEvent_Rc hvrc; | |
436 | struct viodasd_waitevent we; | |
437 | int dev_no = DEVICE_NO(d); | |
438 | struct gendisk *g; | |
439 | struct request_queue *q; | |
440 | u16 flags = 0; | |
441 | ||
442 | retry: | |
443 | init_completion(&we.com); | |
444 | ||
445 | /* Send the open event to OS/400 */ | |
446 | hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp, | |
447 | HvLpEvent_Type_VirtualIo, | |
448 | viomajorsubtype_blockio | vioblockopen, | |
449 | HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck, | |
450 | viopath_sourceinst(viopath_hostLp), | |
451 | viopath_targetinst(viopath_hostLp), | |
452 | (u64)(unsigned long)&we, VIOVERSION << 16, | |
453 | ((u64)dev_no << 48) | ((u64)flags<< 32), | |
454 | 0, 0, 0); | |
455 | if (hvrc != 0) { | |
456 | printk(VIOD_KERN_WARNING "bad rc on HV open %d\n", (int)hvrc); | |
457 | return; | |
458 | } | |
459 | ||
460 | wait_for_completion(&we.com); | |
461 | ||
462 | if (we.rc != 0) { | |
463 | if (flags != 0) | |
464 | return; | |
465 | /* try again with read only flag set */ | |
466 | flags = vioblockflags_ro; | |
467 | goto retry; | |
468 | } | |
469 | if (we.max_disk > (MAX_DISKNO - 1)) { | |
470 | static int warned; | |
471 | ||
472 | if (warned == 0) { | |
473 | warned++; | |
474 | printk(VIOD_KERN_INFO | |
475 | "Only examining the first %d " | |
476 | "of %d disks connected\n", | |
477 | MAX_DISKNO, we.max_disk + 1); | |
478 | } | |
479 | } | |
480 | ||
481 | /* Send the close event to OS/400. We DON'T expect a response */ | |
482 | hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp, | |
483 | HvLpEvent_Type_VirtualIo, | |
484 | viomajorsubtype_blockio | vioblockclose, | |
485 | HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck, | |
486 | viopath_sourceinst(viopath_hostLp), | |
487 | viopath_targetinst(viopath_hostLp), | |
488 | 0, VIOVERSION << 16, | |
489 | ((u64)dev_no << 48) | ((u64)flags << 32), | |
490 | 0, 0, 0); | |
491 | if (hvrc != 0) { | |
492 | printk(VIOD_KERN_WARNING | |
493 | "bad rc sending event to OS/400 %d\n", (int)hvrc); | |
494 | return; | |
495 | } | |
496 | /* create the request queue for the disk */ | |
497 | spin_lock_init(&d->q_lock); | |
498 | q = blk_init_queue(do_viodasd_request, &d->q_lock); | |
499 | if (q == NULL) { | |
500 | printk(VIOD_KERN_WARNING "cannot allocate queue for disk %d\n", | |
501 | dev_no); | |
502 | return; | |
503 | } | |
504 | g = alloc_disk(1 << PARTITION_SHIFT); | |
505 | if (g == NULL) { | |
506 | printk(VIOD_KERN_WARNING | |
507 | "cannot allocate disk structure for disk %d\n", | |
508 | dev_no); | |
509 | blk_cleanup_queue(q); | |
510 | return; | |
511 | } | |
512 | ||
513 | d->disk = g; | |
514 | blk_queue_max_hw_segments(q, VIOMAXBLOCKDMA); | |
515 | blk_queue_max_phys_segments(q, VIOMAXBLOCKDMA); | |
516 | blk_queue_max_sectors(q, VIODASD_MAXSECTORS); | |
517 | g->major = VIODASD_MAJOR; | |
518 | g->first_minor = dev_no << PARTITION_SHIFT; | |
519 | if (dev_no >= 26) | |
520 | snprintf(g->disk_name, sizeof(g->disk_name), | |
521 | VIOD_GENHD_NAME "%c%c", | |
522 | 'a' + (dev_no / 26) - 1, 'a' + (dev_no % 26)); | |
523 | else | |
524 | snprintf(g->disk_name, sizeof(g->disk_name), | |
525 | VIOD_GENHD_NAME "%c", 'a' + (dev_no % 26)); | |
526 | snprintf(g->devfs_name, sizeof(g->devfs_name), | |
527 | "%s%d", VIOD_GENHD_DEVFS_NAME, dev_no); | |
528 | g->fops = &viodasd_fops; | |
529 | g->queue = q; | |
530 | g->private_data = d; | |
531 | g->driverfs_dev = d->dev; | |
532 | set_capacity(g, d->size >> 9); | |
533 | ||
534 | printk(VIOD_KERN_INFO "disk %d: %lu sectors (%lu MB) " | |
535 | "CHS=%d/%d/%d sector size %d%s\n", | |
536 | dev_no, (unsigned long)(d->size >> 9), | |
537 | (unsigned long)(d->size >> 20), | |
538 | (int)d->cylinders, (int)d->tracks, | |
539 | (int)d->sectors, (int)d->bytes_per_sector, | |
540 | d->read_only ? " (RO)" : ""); | |
541 | ||
542 | /* register us in the global list */ | |
543 | add_disk(g); | |
544 | } | |
545 | ||
546 | /* returns the total number of scatterlist elements converted */ | |
547 | static int block_event_to_scatterlist(const struct vioblocklpevent *bevent, | |
548 | struct scatterlist *sg, int *total_len) | |
549 | { | |
550 | int i, numsg; | |
551 | const struct rw_data *rw_data = &bevent->u.rw_data; | |
552 | static const int offset = | |
553 | offsetof(struct vioblocklpevent, u.rw_data.dma_info); | |
554 | static const int element_size = sizeof(rw_data->dma_info[0]); | |
555 | ||
556 | numsg = ((bevent->event.xSizeMinus1 + 1) - offset) / element_size; | |
557 | if (numsg > VIOMAXBLOCKDMA) | |
558 | numsg = VIOMAXBLOCKDMA; | |
559 | ||
560 | *total_len = 0; | |
561 | memset(sg, 0, sizeof(sg[0]) * VIOMAXBLOCKDMA); | |
562 | ||
563 | for (i = 0; (i < numsg) && (rw_data->dma_info[i].len > 0); ++i) { | |
564 | sg_dma_address(&sg[i]) = rw_data->dma_info[i].token; | |
565 | sg_dma_len(&sg[i]) = rw_data->dma_info[i].len; | |
566 | *total_len += rw_data->dma_info[i].len; | |
567 | } | |
568 | return i; | |
569 | } | |
570 | ||
571 | /* | |
572 | * Restart all queues, starting with the one _after_ the disk given, | |
573 | * thus reducing the chance of starvation of higher numbered disks. | |
574 | */ | |
575 | static void viodasd_restart_all_queues_starting_from(int first_index) | |
576 | { | |
577 | int i; | |
578 | ||
579 | for (i = first_index + 1; i < MAX_DISKNO; ++i) | |
580 | if (viodasd_devices[i].disk) | |
581 | blk_run_queue(viodasd_devices[i].disk->queue); | |
582 | for (i = 0; i <= first_index; ++i) | |
583 | if (viodasd_devices[i].disk) | |
584 | blk_run_queue(viodasd_devices[i].disk->queue); | |
585 | } | |
586 | ||
587 | /* | |
588 | * For read and write requests, decrement the number of outstanding requests, | |
589 | * Free the DMA buffers we allocated. | |
590 | */ | |
591 | static int viodasd_handle_read_write(struct vioblocklpevent *bevent) | |
592 | { | |
593 | int num_sg, num_sect, pci_direction, total_len; | |
594 | struct request *req; | |
595 | struct scatterlist sg[VIOMAXBLOCKDMA]; | |
596 | struct HvLpEvent *event = &bevent->event; | |
597 | unsigned long irq_flags; | |
598 | struct viodasd_device *d; | |
599 | int error; | |
600 | spinlock_t *qlock; | |
601 | ||
602 | num_sg = block_event_to_scatterlist(bevent, sg, &total_len); | |
603 | num_sect = total_len >> 9; | |
604 | if (event->xSubtype == (viomajorsubtype_blockio | vioblockread)) | |
605 | pci_direction = DMA_FROM_DEVICE; | |
606 | else | |
607 | pci_direction = DMA_TO_DEVICE; | |
608 | req = (struct request *)bevent->event.xCorrelationToken; | |
609 | d = req->rq_disk->private_data; | |
610 | ||
611 | dma_unmap_sg(d->dev, sg, num_sg, pci_direction); | |
612 | ||
613 | /* | |
614 | * Since this is running in interrupt mode, we need to make sure | |
615 | * we're not stepping on any global I/O operations | |
616 | */ | |
617 | spin_lock_irqsave(&viodasd_spinlock, irq_flags); | |
618 | num_req_outstanding--; | |
619 | spin_unlock_irqrestore(&viodasd_spinlock, irq_flags); | |
620 | ||
621 | error = event->xRc != HvLpEvent_Rc_Good; | |
622 | if (error) { | |
623 | const struct vio_error_entry *err; | |
624 | err = vio_lookup_rc(viodasd_err_table, bevent->sub_result); | |
625 | printk(VIOD_KERN_WARNING "read/write error %d:0x%04x (%s)\n", | |
626 | event->xRc, bevent->sub_result, err->msg); | |
627 | num_sect = req->hard_nr_sectors; | |
628 | } | |
629 | qlock = req->q->queue_lock; | |
630 | spin_lock_irqsave(qlock, irq_flags); | |
631 | viodasd_end_request(req, !error, num_sect); | |
632 | spin_unlock_irqrestore(qlock, irq_flags); | |
633 | ||
634 | /* Finally, try to get more requests off of this device's queue */ | |
635 | viodasd_restart_all_queues_starting_from(DEVICE_NO(d)); | |
636 | ||
637 | return 0; | |
638 | } | |
639 | ||
640 | /* This routine handles incoming block LP events */ | |
641 | static void handle_block_event(struct HvLpEvent *event) | |
642 | { | |
643 | struct vioblocklpevent *bevent = (struct vioblocklpevent *)event; | |
644 | struct viodasd_waitevent *pwe; | |
645 | ||
646 | if (event == NULL) | |
647 | /* Notification that a partition went away! */ | |
648 | return; | |
649 | /* First, we should NEVER get an int here...only acks */ | |
677f8c0d | 650 | if (hvlpevent_is_int(event)) { |
1da177e4 LT |
651 | printk(VIOD_KERN_WARNING |
652 | "Yikes! got an int in viodasd event handler!\n"); | |
677f8c0d | 653 | if (hvlpevent_need_ack(event)) { |
1da177e4 LT |
654 | event->xRc = HvLpEvent_Rc_InvalidSubtype; |
655 | HvCallEvent_ackLpEvent(event); | |
656 | } | |
657 | } | |
658 | ||
659 | switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) { | |
660 | case vioblockopen: | |
661 | /* | |
662 | * Handle a response to an open request. We get all the | |
663 | * disk information in the response, so update it. The | |
664 | * correlation token contains a pointer to a waitevent | |
665 | * structure that has a completion in it. update the | |
666 | * return code in the waitevent structure and post the | |
667 | * completion to wake up the guy who sent the request | |
668 | */ | |
669 | pwe = (struct viodasd_waitevent *)event->xCorrelationToken; | |
670 | pwe->rc = event->xRc; | |
671 | pwe->sub_result = bevent->sub_result; | |
672 | if (event->xRc == HvLpEvent_Rc_Good) { | |
673 | const struct open_data *data = &bevent->u.open_data; | |
674 | struct viodasd_device *device = | |
675 | &viodasd_devices[bevent->disk]; | |
676 | device->read_only = | |
677 | bevent->flags & vioblockflags_ro; | |
678 | device->size = data->disk_size; | |
679 | device->cylinders = data->cylinders; | |
680 | device->tracks = data->tracks; | |
681 | device->sectors = data->sectors; | |
682 | device->bytes_per_sector = data->bytes_per_sector; | |
683 | pwe->max_disk = data->max_disk; | |
684 | } | |
685 | complete(&pwe->com); | |
686 | break; | |
687 | case vioblockclose: | |
688 | break; | |
689 | case vioblockread: | |
690 | case vioblockwrite: | |
691 | viodasd_handle_read_write(bevent); | |
692 | break; | |
693 | ||
694 | default: | |
695 | printk(VIOD_KERN_WARNING "invalid subtype!"); | |
677f8c0d | 696 | if (hvlpevent_need_ack(event)) { |
1da177e4 LT |
697 | event->xRc = HvLpEvent_Rc_InvalidSubtype; |
698 | HvCallEvent_ackLpEvent(event); | |
699 | } | |
700 | } | |
701 | } | |
702 | ||
703 | /* | |
704 | * Get the driver to reprobe for more disks. | |
705 | */ | |
706 | static ssize_t probe_disks(struct device_driver *drv, const char *buf, | |
707 | size_t count) | |
708 | { | |
709 | struct viodasd_device *d; | |
710 | ||
711 | for (d = viodasd_devices; d < &viodasd_devices[MAX_DISKNO]; d++) { | |
712 | if (d->disk == NULL) | |
713 | probe_disk(d); | |
714 | } | |
715 | return count; | |
716 | } | |
717 | static DRIVER_ATTR(probe, S_IWUSR, NULL, probe_disks); | |
718 | ||
719 | static int viodasd_probe(struct vio_dev *vdev, const struct vio_device_id *id) | |
720 | { | |
721 | struct viodasd_device *d = &viodasd_devices[vdev->unit_address]; | |
722 | ||
723 | d->dev = &vdev->dev; | |
724 | probe_disk(d); | |
725 | if (d->disk == NULL) | |
726 | return -ENODEV; | |
727 | return 0; | |
728 | } | |
729 | ||
730 | static int viodasd_remove(struct vio_dev *vdev) | |
731 | { | |
732 | struct viodasd_device *d; | |
733 | ||
734 | d = &viodasd_devices[vdev->unit_address]; | |
735 | if (d->disk) { | |
736 | del_gendisk(d->disk); | |
737 | blk_cleanup_queue(d->disk->queue); | |
738 | put_disk(d->disk); | |
739 | d->disk = NULL; | |
740 | } | |
741 | d->dev = NULL; | |
742 | return 0; | |
743 | } | |
744 | ||
745 | /** | |
746 | * viodasd_device_table: Used by vio.c to match devices that we | |
747 | * support. | |
748 | */ | |
749 | static struct vio_device_id viodasd_device_table[] __devinitdata = { | |
fbabeb60 | 750 | { "block", "IBM,iSeries-viodasd" }, |
fb120da6 | 751 | { "", "" } |
1da177e4 | 752 | }; |
1da177e4 | 753 | MODULE_DEVICE_TABLE(vio, viodasd_device_table); |
915124d8 | 754 | |
1da177e4 | 755 | static struct vio_driver viodasd_driver = { |
1da177e4 LT |
756 | .id_table = viodasd_device_table, |
757 | .probe = viodasd_probe, | |
6fdf5392 SR |
758 | .remove = viodasd_remove, |
759 | .driver = { | |
760 | .name = "viodasd", | |
915124d8 | 761 | .owner = THIS_MODULE, |
6fdf5392 | 762 | } |
1da177e4 LT |
763 | }; |
764 | ||
765 | /* | |
766 | * Initialize the whole device driver. Handle module and non-module | |
767 | * versions | |
768 | */ | |
769 | static int __init viodasd_init(void) | |
770 | { | |
771 | int rc; | |
772 | ||
773 | /* Try to open to our host lp */ | |
774 | if (viopath_hostLp == HvLpIndexInvalid) | |
775 | vio_set_hostlp(); | |
776 | ||
777 | if (viopath_hostLp == HvLpIndexInvalid) { | |
778 | printk(VIOD_KERN_WARNING "invalid hosting partition\n"); | |
779 | return -EIO; | |
780 | } | |
781 | ||
782 | printk(VIOD_KERN_INFO "vers " VIOD_VERS ", hosting partition %d\n", | |
783 | viopath_hostLp); | |
784 | ||
785 | /* register the block device */ | |
786 | if (register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME)) { | |
787 | printk(VIOD_KERN_WARNING | |
788 | "Unable to get major number %d for %s\n", | |
789 | VIODASD_MAJOR, VIOD_GENHD_NAME); | |
790 | return -EIO; | |
791 | } | |
792 | /* Actually open the path to the hosting partition */ | |
793 | if (viopath_open(viopath_hostLp, viomajorsubtype_blockio, | |
794 | VIOMAXREQ + 2)) { | |
795 | printk(VIOD_KERN_WARNING | |
796 | "error opening path to host partition %d\n", | |
797 | viopath_hostLp); | |
798 | unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME); | |
799 | return -EIO; | |
800 | } | |
801 | ||
802 | /* Initialize our request handler */ | |
803 | vio_setHandler(viomajorsubtype_blockio, handle_block_event); | |
804 | ||
805 | rc = vio_register_driver(&viodasd_driver); | |
806 | if (rc == 0) | |
807 | driver_create_file(&viodasd_driver.driver, &driver_attr_probe); | |
808 | return rc; | |
809 | } | |
810 | module_init(viodasd_init); | |
811 | ||
812 | void viodasd_exit(void) | |
813 | { | |
814 | driver_remove_file(&viodasd_driver.driver, &driver_attr_probe); | |
815 | vio_unregister_driver(&viodasd_driver); | |
816 | vio_clearHandler(viomajorsubtype_blockio); | |
817 | unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME); | |
818 | viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2); | |
819 | } | |
820 | ||
821 | module_exit(viodasd_exit); |