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1/*
2 *	Block OSM
3 *
4 * 	Copyright (C) 1999-2002	Red Hat Software
5 *
6 *	Written by Alan Cox, Building Number Three Ltd
7 *
8 *	This program is free software; you can redistribute it and/or modify it
9 *	under the terms of the GNU General Public License as published by the
10 *	Free Software Foundation; either version 2 of the License, or (at your
11 *	option) any later version.
12 *
13 *	This program is distributed in the hope that it will be useful, but
14 *	WITHOUT ANY WARRANTY; without even the implied warranty of
15 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 *	General Public License for more details.
17 *
18 *	For the purpose of avoiding doubt the preferred form of the work
19 *	for making modifications shall be a standards compliant form such
20 *	gzipped tar and not one requiring a proprietary or patent encumbered
21 *	tool to unpack.
22 *
23 *	Fixes/additions:
24 *		Steve Ralston:
25 *			Multiple device handling error fixes,
26 *			Added a queue depth.
27 *		Alan Cox:
28 *			FC920 has an rmw bug. Dont or in the end marker.
29 *			Removed queue walk, fixed for 64bitness.
30 *			Rewrote much of the code over time
31 *			Added indirect block lists
32 *			Handle 64K limits on many controllers
33 *			Don't use indirects on the Promise (breaks)
34 *			Heavily chop down the queue depths
35 *		Deepak Saxena:
36 *			Independent queues per IOP
37 *			Support for dynamic device creation/deletion
38 *			Code cleanup
39 *	    		Support for larger I/Os through merge* functions
40 *			(taken from DAC960 driver)
41 *		Boji T Kannanthanam:
42 *			Set the I2O Block devices to be detected in increasing
43 *			order of TIDs during boot.
44 *			Search and set the I2O block device that we boot off
45 *			from as the first device to be claimed (as /dev/i2o/hda)
46 *			Properly attach/detach I2O gendisk structure from the
47 *			system gendisk list. The I2O block devices now appear in
48 *			/proc/partitions.
49 *		Markus Lidel <Markus.Lidel@shadowconnect.com>:
50 *			Minor bugfixes for 2.6.
51 */
52
53#include <linux/module.h>
54#include <linux/slab.h>
55#include <linux/i2o.h>
56#include <linux/smp_lock.h>
57
58#include <linux/mempool.h>
59
60#include <linux/genhd.h>
61#include <linux/blkdev.h>
62#include <linux/hdreg.h>
63
64#include <scsi/scsi.h>
65
66#include "i2o_block.h"
67
68#define OSM_NAME	"block-osm"
69#define OSM_VERSION	"1.325"
70#define OSM_DESCRIPTION	"I2O Block Device OSM"
71
72static struct i2o_driver i2o_block_driver;
73
74/* global Block OSM request mempool */
75static struct i2o_block_mempool i2o_blk_req_pool;
76
77/* Block OSM class handling definition */
78static struct i2o_class_id i2o_block_class_id[] = {
79	{I2O_CLASS_RANDOM_BLOCK_STORAGE},
80	{I2O_CLASS_END}
81};
82
83/**
84 *	i2o_block_device_free - free the memory of the I2O Block device
85 *	@dev: I2O Block device, which should be cleaned up
86 *
87 *	Frees the request queue, gendisk and the i2o_block_device structure.
88 */
89static void i2o_block_device_free(struct i2o_block_device *dev)
90{
91	blk_cleanup_queue(dev->gd->queue);
92
93	put_disk(dev->gd);
94
95	kfree(dev);
96};
97
98/**
99 *	i2o_block_remove - remove the I2O Block device from the system again
100 *	@dev: I2O Block device which should be removed
101 *
102 *	Remove gendisk from system and free all allocated memory.
103 *
104 *	Always returns 0.
105 */
106static int i2o_block_remove(struct device *dev)
107{
108	struct i2o_device *i2o_dev = to_i2o_device(dev);
109	struct i2o_block_device *i2o_blk_dev = dev_get_drvdata(dev);
110
111	osm_info("device removed (TID: %03x): %s\n", i2o_dev->lct_data.tid,
112		 i2o_blk_dev->gd->disk_name);
113
114	i2o_event_register(i2o_dev, &i2o_block_driver, 0, 0);
115
116	del_gendisk(i2o_blk_dev->gd);
117
118	dev_set_drvdata(dev, NULL);
119
120	i2o_device_claim_release(i2o_dev);
121
122	i2o_block_device_free(i2o_blk_dev);
123
124	return 0;
125};
126
127/**
128 *	i2o_block_device flush - Flush all dirty data of I2O device dev
129 *	@dev: I2O device which should be flushed
130 *
131 *	Flushes all dirty data on device dev.
132 *
133 *	Returns 0 on success or negative error code on failure.
134 */
135static int i2o_block_device_flush(struct i2o_device *dev)
136{
137	struct i2o_message *msg;
138
139	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
140	if (IS_ERR(msg))
141		return PTR_ERR(msg);
142
143	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
144	msg->u.head[1] =
145	    cpu_to_le32(I2O_CMD_BLOCK_CFLUSH << 24 | HOST_TID << 12 | dev->
146			lct_data.tid);
147	msg->body[0] = cpu_to_le32(60 << 16);
148	osm_debug("Flushing...\n");
149
150	return i2o_msg_post_wait(dev->iop, msg, 60);
151};
152
153/**
154 *	i2o_block_device_mount - Mount (load) the media of device dev
155 *	@dev: I2O device which should receive the mount request
156 *	@media_id: Media Identifier
157 *
158 *	Load a media into drive. Identifier should be set to -1, because the
159 *	spec does not support any other value.
160 *
161 *	Returns 0 on success or negative error code on failure.
162 */
163static int i2o_block_device_mount(struct i2o_device *dev, u32 media_id)
164{
165	struct i2o_message *msg;
166
167	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
168	if (IS_ERR(msg))
169		return PTR_ERR(msg);
170
171	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
172	msg->u.head[1] =
173	    cpu_to_le32(I2O_CMD_BLOCK_MMOUNT << 24 | HOST_TID << 12 | dev->
174			lct_data.tid);
175	msg->body[0] = cpu_to_le32(-1);
176	msg->body[1] = cpu_to_le32(0x00000000);
177	osm_debug("Mounting...\n");
178
179	return i2o_msg_post_wait(dev->iop, msg, 2);
180};
181
182/**
183 *	i2o_block_device_lock - Locks the media of device dev
184 *	@dev: I2O device which should receive the lock request
185 *	@media_id: Media Identifier
186 *
187 *	Lock media of device dev to prevent removal. The media identifier
188 *	should be set to -1, because the spec does not support any other value.
189 *
190 *	Returns 0 on success or negative error code on failure.
191 */
192static int i2o_block_device_lock(struct i2o_device *dev, u32 media_id)
193{
194	struct i2o_message *msg;
195
196	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
197	if (IS_ERR(msg))
198		return PTR_ERR(msg);
199
200	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
201	msg->u.head[1] =
202	    cpu_to_le32(I2O_CMD_BLOCK_MLOCK << 24 | HOST_TID << 12 | dev->
203			lct_data.tid);
204	msg->body[0] = cpu_to_le32(-1);
205	osm_debug("Locking...\n");
206
207	return i2o_msg_post_wait(dev->iop, msg, 2);
208};
209
210/**
211 *	i2o_block_device_unlock - Unlocks the media of device dev
212 *	@dev: I2O device which should receive the unlocked request
213 *	@media_id: Media Identifier
214 *
215 *	Unlocks the media in device dev. The media identifier should be set to
216 *	-1, because the spec does not support any other value.
217 *
218 *	Returns 0 on success or negative error code on failure.
219 */
220static int i2o_block_device_unlock(struct i2o_device *dev, u32 media_id)
221{
222	struct i2o_message *msg;
223
224	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
225	if (IS_ERR(msg))
226		return PTR_ERR(msg);
227
228	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
229	msg->u.head[1] =
230	    cpu_to_le32(I2O_CMD_BLOCK_MUNLOCK << 24 | HOST_TID << 12 | dev->
231			lct_data.tid);
232	msg->body[0] = cpu_to_le32(media_id);
233	osm_debug("Unlocking...\n");
234
235	return i2o_msg_post_wait(dev->iop, msg, 2);
236};
237
238/**
239 *	i2o_block_device_power - Power management for device dev
240 *	@dev: I2O device which should receive the power management request
241 *	@op: Operation to send
242 *
243 *	Send a power management request to the device dev.
244 *
245 *	Returns 0 on success or negative error code on failure.
246 */
247static int i2o_block_device_power(struct i2o_block_device *dev, u8 op)
248{
249	struct i2o_device *i2o_dev = dev->i2o_dev;
250	struct i2o_controller *c = i2o_dev->iop;
251	struct i2o_message *msg;
252	int rc;
253
254	msg = i2o_msg_get_wait(c, I2O_TIMEOUT_MESSAGE_GET);
255	if (IS_ERR(msg))
256		return PTR_ERR(msg);
257
258	msg->u.head[0] = cpu_to_le32(FOUR_WORD_MSG_SIZE | SGL_OFFSET_0);
259	msg->u.head[1] =
260	    cpu_to_le32(I2O_CMD_BLOCK_POWER << 24 | HOST_TID << 12 | i2o_dev->
261			lct_data.tid);
262	msg->body[0] = cpu_to_le32(op << 24);
263	osm_debug("Power...\n");
264
265	rc = i2o_msg_post_wait(c, msg, 60);
266	if (!rc)
267		dev->power = op;
268
269	return rc;
270};
271
272/**
273 *	i2o_block_request_alloc - Allocate an I2O block request struct
274 *
275 *	Allocates an I2O block request struct and initialize the list.
276 *
277 *	Returns a i2o_block_request pointer on success or negative error code
278 *	on failure.
279 */
280static inline struct i2o_block_request *i2o_block_request_alloc(void)
281{
282	struct i2o_block_request *ireq;
283
284	ireq = mempool_alloc(i2o_blk_req_pool.pool, GFP_ATOMIC);
285	if (!ireq)
286		return ERR_PTR(-ENOMEM);
287
288	INIT_LIST_HEAD(&ireq->queue);
289	sg_init_table(ireq->sg_table, I2O_MAX_PHYS_SEGMENTS);
290
291	return ireq;
292};
293
294/**
295 *	i2o_block_request_free - Frees a I2O block request
296 *	@ireq: I2O block request which should be freed
297 *
298 *	Frees the allocated memory (give it back to the request mempool).
299 */
300static inline void i2o_block_request_free(struct i2o_block_request *ireq)
301{
302	mempool_free(ireq, i2o_blk_req_pool.pool);
303};
304
305/**
306 *	i2o_block_sglist_alloc - Allocate the SG list and map it
307 *	@c: I2O controller to which the request belongs
308 *	@ireq: I2O block request
309 *	@mptr: message body pointer
310 *
311 *	Builds the SG list and map it to be accessable by the controller.
312 *
313 *	Returns 0 on failure or 1 on success.
314 */
315static inline int i2o_block_sglist_alloc(struct i2o_controller *c,
316					 struct i2o_block_request *ireq,
317					 u32 ** mptr)
318{
319	int nents;
320	enum dma_data_direction direction;
321
322	ireq->dev = &c->pdev->dev;
323	nents = blk_rq_map_sg(ireq->req->q, ireq->req, ireq->sg_table);
324
325	if (rq_data_dir(ireq->req) == READ)
326		direction = PCI_DMA_FROMDEVICE;
327	else
328		direction = PCI_DMA_TODEVICE;
329
330	ireq->sg_nents = nents;
331
332	return i2o_dma_map_sg(c, ireq->sg_table, nents, direction, mptr);
333};
334
335/**
336 *	i2o_block_sglist_free - Frees the SG list
337 *	@ireq: I2O block request from which the SG should be freed
338 *
339 *	Frees the SG list from the I2O block request.
340 */
341static inline void i2o_block_sglist_free(struct i2o_block_request *ireq)
342{
343	enum dma_data_direction direction;
344
345	if (rq_data_dir(ireq->req) == READ)
346		direction = PCI_DMA_FROMDEVICE;
347	else
348		direction = PCI_DMA_TODEVICE;
349
350	dma_unmap_sg(ireq->dev, ireq->sg_table, ireq->sg_nents, direction);
351};
352
353/**
354 *	i2o_block_prep_req_fn - Allocates I2O block device specific struct
355 *	@q: request queue for the request
356 *	@req: the request to prepare
357 *
358 *	Allocate the necessary i2o_block_request struct and connect it to
359 *	the request. This is needed that we not lose the SG list later on.
360 *
361 *	Returns BLKPREP_OK on success or BLKPREP_DEFER on failure.
362 */
363static int i2o_block_prep_req_fn(struct request_queue *q, struct request *req)
364{
365	struct i2o_block_device *i2o_blk_dev = q->queuedata;
366	struct i2o_block_request *ireq;
367
368	if (unlikely(!i2o_blk_dev)) {
369		osm_err("block device already removed\n");
370		return BLKPREP_KILL;
371	}
372
373	/* connect the i2o_block_request to the request */
374	if (!req->special) {
375		ireq = i2o_block_request_alloc();
376		if (IS_ERR(ireq)) {
377			osm_debug("unable to allocate i2o_block_request!\n");
378			return BLKPREP_DEFER;
379		}
380
381		ireq->i2o_blk_dev = i2o_blk_dev;
382		req->special = ireq;
383		ireq->req = req;
384	}
385	/* do not come back here */
386	req->cmd_flags |= REQ_DONTPREP;
387
388	return BLKPREP_OK;
389};
390
391/**
392 *	i2o_block_delayed_request_fn - delayed request queue function
393 *	@work: the delayed request with the queue to start
394 *
395 *	If the request queue is stopped for a disk, and there is no open
396 *	request, a new event is created, which calls this function to start
397 *	the queue after I2O_BLOCK_REQUEST_TIME. Otherwise the queue will never
398 *	be started again.
399 */
400static void i2o_block_delayed_request_fn(struct work_struct *work)
401{
402	struct i2o_block_delayed_request *dreq =
403		container_of(work, struct i2o_block_delayed_request,
404			     work.work);
405	struct request_queue *q = dreq->queue;
406	unsigned long flags;
407
408	spin_lock_irqsave(q->queue_lock, flags);
409	blk_start_queue(q);
410	spin_unlock_irqrestore(q->queue_lock, flags);
411	kfree(dreq);
412};
413
414/**
415 *	i2o_block_end_request - Post-processing of completed commands
416 *	@req: request which should be completed
417 *	@error: 0 for success, < 0 for error
418 *	@nr_bytes: number of bytes to complete
419 *
420 *	Mark the request as complete. The lock must not be held when entering.
421 *
422 */
423static void i2o_block_end_request(struct request *req, int error,
424				  int nr_bytes)
425{
426	struct i2o_block_request *ireq = req->special;
427	struct i2o_block_device *dev = ireq->i2o_blk_dev;
428	struct request_queue *q = req->q;
429	unsigned long flags;
430
431	if (blk_end_request(req, error, nr_bytes))
432		if (error)
433			blk_end_request_all(req, -EIO);
434
435	spin_lock_irqsave(q->queue_lock, flags);
436
437	if (likely(dev)) {
438		dev->open_queue_depth--;
439		list_del(&ireq->queue);
440	}
441
442	blk_start_queue(q);
443
444	spin_unlock_irqrestore(q->queue_lock, flags);
445
446	i2o_block_sglist_free(ireq);
447	i2o_block_request_free(ireq);
448};
449
450/**
451 *	i2o_block_reply - Block OSM reply handler.
452 *	@c: I2O controller from which the message arrives
453 *	@m: message id of reply
454 *	@msg: the actual I2O message reply
455 *
456 *	This function gets all the message replies.
457 *
458 */
459static int i2o_block_reply(struct i2o_controller *c, u32 m,
460			   struct i2o_message *msg)
461{
462	struct request *req;
463	int error = 0;
464
465	req = i2o_cntxt_list_get(c, le32_to_cpu(msg->u.s.tcntxt));
466	if (unlikely(!req)) {
467		osm_err("NULL reply received!\n");
468		return -1;
469	}
470
471	/*
472	 *      Lets see what is cooking. We stuffed the
473	 *      request in the context.
474	 */
475
476	if ((le32_to_cpu(msg->body[0]) >> 24) != 0) {
477		u32 status = le32_to_cpu(msg->body[0]);
478		/*
479		 *      Device not ready means two things. One is that the
480		 *      the thing went offline (but not a removal media)
481		 *
482		 *      The second is that you have a SuperTrak 100 and the
483		 *      firmware got constipated. Unlike standard i2o card
484		 *      setups the supertrak returns an error rather than
485		 *      blocking for the timeout in these cases.
486		 *
487		 *      Don't stick a supertrak100 into cache aggressive modes
488		 */
489
490		osm_err("TID %03x error status: 0x%02x, detailed status: "
491			"0x%04x\n", (le32_to_cpu(msg->u.head[1]) >> 12 & 0xfff),
492			status >> 24, status & 0xffff);
493
494		req->errors++;
495
496		error = -EIO;
497	}
498
499	i2o_block_end_request(req, error, le32_to_cpu(msg->body[1]));
500
501	return 1;
502};
503
504static void i2o_block_event(struct work_struct *work)
505{
506	struct i2o_event *evt = container_of(work, struct i2o_event, work);
507	osm_debug("event received\n");
508	kfree(evt);
509};
510
511/*
512 *	SCSI-CAM for ioctl geometry mapping
513 *	Duplicated with SCSI - this should be moved into somewhere common
514 *	perhaps genhd ?
515 *
516 * LBA -> CHS mapping table taken from:
517 *
518 * "Incorporating the I2O Architecture into BIOS for Intel Architecture
519 *  Platforms"
520 *
521 * This is an I2O document that is only available to I2O members,
522 * not developers.
523 *
524 * From my understanding, this is how all the I2O cards do this
525 *
526 * Disk Size      | Sectors | Heads | Cylinders
527 * ---------------+---------+-------+-------------------
528 * 1 < X <= 528M  | 63      | 16    | X/(63 * 16 * 512)
529 * 528M < X <= 1G | 63      | 32    | X/(63 * 32 * 512)
530 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
531 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
532 *
533 */
534#define	BLOCK_SIZE_528M		1081344
535#define	BLOCK_SIZE_1G		2097152
536#define	BLOCK_SIZE_21G		4403200
537#define	BLOCK_SIZE_42G		8806400
538#define	BLOCK_SIZE_84G		17612800
539
540static void i2o_block_biosparam(unsigned long capacity, unsigned short *cyls,
541				unsigned char *hds, unsigned char *secs)
542{
543	unsigned long heads, sectors, cylinders;
544
545	sectors = 63L;		/* Maximize sectors per track */
546	if (capacity <= BLOCK_SIZE_528M)
547		heads = 16;
548	else if (capacity <= BLOCK_SIZE_1G)
549		heads = 32;
550	else if (capacity <= BLOCK_SIZE_21G)
551		heads = 64;
552	else if (capacity <= BLOCK_SIZE_42G)
553		heads = 128;
554	else
555		heads = 255;
556
557	cylinders = (unsigned long)capacity / (heads * sectors);
558
559	*cyls = (unsigned short)cylinders;	/* Stuff return values */
560	*secs = (unsigned char)sectors;
561	*hds = (unsigned char)heads;
562}
563
564/**
565 *	i2o_block_open - Open the block device
566 *	@bdev: block device being opened
567 *	@mode: file open mode
568 *
569 *	Power up the device, mount and lock the media. This function is called,
570 *	if the block device is opened for access.
571 *
572 *	Returns 0 on success or negative error code on failure.
573 */
574static int i2o_block_open(struct block_device *bdev, fmode_t mode)
575{
576	struct i2o_block_device *dev = bdev->bd_disk->private_data;
577
578	if (!dev->i2o_dev)
579		return -ENODEV;
580
581	lock_kernel();
582	if (dev->power > 0x1f)
583		i2o_block_device_power(dev, 0x02);
584
585	i2o_block_device_mount(dev->i2o_dev, -1);
586
587	i2o_block_device_lock(dev->i2o_dev, -1);
588
589	osm_debug("Ready.\n");
590	unlock_kernel();
591
592	return 0;
593};
594
595/**
596 *	i2o_block_release - Release the I2O block device
597 *	@disk: gendisk device being released
598 *	@mode: file open mode
599 *
600 *	Unlock and unmount the media, and power down the device. Gets called if
601 *	the block device is closed.
602 *
603 *	Returns 0 on success or negative error code on failure.
604 */
605static int i2o_block_release(struct gendisk *disk, fmode_t mode)
606{
607	struct i2o_block_device *dev = disk->private_data;
608	u8 operation;
609
610	/*
611	 * This is to deail with the case of an application
612	 * opening a device and then the device dissapears while
613	 * it's in use, and then the application tries to release
614	 * it.  ex: Unmounting a deleted RAID volume at reboot.
615	 * If we send messages, it will just cause FAILs since
616	 * the TID no longer exists.
617	 */
618	if (!dev->i2o_dev)
619		return 0;
620
621	lock_kernel();
622	i2o_block_device_flush(dev->i2o_dev);
623
624	i2o_block_device_unlock(dev->i2o_dev, -1);
625
626	if (dev->flags & (1 << 3 | 1 << 4))	/* Removable */
627		operation = 0x21;
628	else
629		operation = 0x24;
630
631	i2o_block_device_power(dev, operation);
632	unlock_kernel();
633
634	return 0;
635}
636
637static int i2o_block_getgeo(struct block_device *bdev, struct hd_geometry *geo)
638{
639	i2o_block_biosparam(get_capacity(bdev->bd_disk),
640			    &geo->cylinders, &geo->heads, &geo->sectors);
641	return 0;
642}
643
644/**
645 *	i2o_block_ioctl - Issue device specific ioctl calls.
646 *	@bdev: block device being opened
647 *	@mode: file open mode
648 *	@cmd: ioctl command
649 *	@arg: arg
650 *
651 *	Handles ioctl request for the block device.
652 *
653 *	Return 0 on success or negative error on failure.
654 */
655static int i2o_block_ioctl(struct block_device *bdev, fmode_t mode,
656			   unsigned int cmd, unsigned long arg)
657{
658	struct gendisk *disk = bdev->bd_disk;
659	struct i2o_block_device *dev = disk->private_data;
660	int ret = -ENOTTY;
661
662	/* Anyone capable of this syscall can do *real bad* things */
663
664	if (!capable(CAP_SYS_ADMIN))
665		return -EPERM;
666
667	lock_kernel();
668	switch (cmd) {
669	case BLKI2OGRSTRAT:
670		ret = put_user(dev->rcache, (int __user *)arg);
671		break;
672	case BLKI2OGWSTRAT:
673		ret = put_user(dev->wcache, (int __user *)arg);
674		break;
675	case BLKI2OSRSTRAT:
676		ret = -EINVAL;
677		if (arg < 0 || arg > CACHE_SMARTFETCH)
678			break;
679		dev->rcache = arg;
680		ret = 0;
681		break;
682	case BLKI2OSWSTRAT:
683		ret = -EINVAL;
684		if (arg != 0
685		    && (arg < CACHE_WRITETHROUGH || arg > CACHE_SMARTBACK))
686			break;
687		dev->wcache = arg;
688		ret = 0;
689		break;
690	}
691	unlock_kernel();
692
693	return ret;
694};
695
696/**
697 *	i2o_block_media_changed - Have we seen a media change?
698 *	@disk: gendisk which should be verified
699 *
700 *	Verifies if the media has changed.
701 *
702 *	Returns 1 if the media was changed or 0 otherwise.
703 */
704static int i2o_block_media_changed(struct gendisk *disk)
705{
706	struct i2o_block_device *p = disk->private_data;
707
708	if (p->media_change_flag) {
709		p->media_change_flag = 0;
710		return 1;
711	}
712	return 0;
713}
714
715/**
716 *	i2o_block_transfer - Transfer a request to/from the I2O controller
717 *	@req: the request which should be transfered
718 *
719 *	This function converts the request into a I2O message. The necessary
720 *	DMA buffers are allocated and after everything is setup post the message
721 *	to the I2O controller. No cleanup is done by this function. It is done
722 *	on the interrupt side when the reply arrives.
723 *
724 *	Return 0 on success or negative error code on failure.
725 */
726static int i2o_block_transfer(struct request *req)
727{
728	struct i2o_block_device *dev = req->rq_disk->private_data;
729	struct i2o_controller *c;
730	u32 tid;
731	struct i2o_message *msg;
732	u32 *mptr;
733	struct i2o_block_request *ireq = req->special;
734	u32 tcntxt;
735	u32 sgl_offset = SGL_OFFSET_8;
736	u32 ctl_flags = 0x00000000;
737	int rc;
738	u32 cmd;
739
740	if (unlikely(!dev->i2o_dev)) {
741		osm_err("transfer to removed drive\n");
742		rc = -ENODEV;
743		goto exit;
744	}
745
746	tid = dev->i2o_dev->lct_data.tid;
747	c = dev->i2o_dev->iop;
748
749	msg = i2o_msg_get(c);
750	if (IS_ERR(msg)) {
751		rc = PTR_ERR(msg);
752		goto exit;
753	}
754
755	tcntxt = i2o_cntxt_list_add(c, req);
756	if (!tcntxt) {
757		rc = -ENOMEM;
758		goto nop_msg;
759	}
760
761	msg->u.s.icntxt = cpu_to_le32(i2o_block_driver.context);
762	msg->u.s.tcntxt = cpu_to_le32(tcntxt);
763
764	mptr = &msg->body[0];
765
766	if (rq_data_dir(req) == READ) {
767		cmd = I2O_CMD_BLOCK_READ << 24;
768
769		switch (dev->rcache) {
770		case CACHE_PREFETCH:
771			ctl_flags = 0x201F0008;
772			break;
773
774		case CACHE_SMARTFETCH:
775			if (blk_rq_sectors(req) > 16)
776				ctl_flags = 0x201F0008;
777			else
778				ctl_flags = 0x001F0000;
779			break;
780
781		default:
782			break;
783		}
784	} else {
785		cmd = I2O_CMD_BLOCK_WRITE << 24;
786
787		switch (dev->wcache) {
788		case CACHE_WRITETHROUGH:
789			ctl_flags = 0x001F0008;
790			break;
791		case CACHE_WRITEBACK:
792			ctl_flags = 0x001F0010;
793			break;
794		case CACHE_SMARTBACK:
795			if (blk_rq_sectors(req) > 16)
796				ctl_flags = 0x001F0004;
797			else
798				ctl_flags = 0x001F0010;
799			break;
800		case CACHE_SMARTTHROUGH:
801			if (blk_rq_sectors(req) > 16)
802				ctl_flags = 0x001F0004;
803			else
804				ctl_flags = 0x001F0010;
805		default:
806			break;
807		}
808	}
809
810#ifdef CONFIG_I2O_EXT_ADAPTEC
811	if (c->adaptec) {
812		u8 cmd[10];
813		u32 scsi_flags;
814		u16 hwsec;
815
816		hwsec = queue_logical_block_size(req->q) >> KERNEL_SECTOR_SHIFT;
817		memset(cmd, 0, 10);
818
819		sgl_offset = SGL_OFFSET_12;
820
821		msg->u.head[1] =
822		    cpu_to_le32(I2O_CMD_PRIVATE << 24 | HOST_TID << 12 | tid);
823
824		*mptr++ = cpu_to_le32(I2O_VENDOR_DPT << 16 | I2O_CMD_SCSI_EXEC);
825		*mptr++ = cpu_to_le32(tid);
826
827		/*
828		 * ENABLE_DISCONNECT
829		 * SIMPLE_TAG
830		 * RETURN_SENSE_DATA_IN_REPLY_MESSAGE_FRAME
831		 */
832		if (rq_data_dir(req) == READ) {
833			cmd[0] = READ_10;
834			scsi_flags = 0x60a0000a;
835		} else {
836			cmd[0] = WRITE_10;
837			scsi_flags = 0xa0a0000a;
838		}
839
840		*mptr++ = cpu_to_le32(scsi_flags);
841
842		*((u32 *) & cmd[2]) = cpu_to_be32(blk_rq_pos(req) * hwsec);
843		*((u16 *) & cmd[7]) = cpu_to_be16(blk_rq_sectors(req) * hwsec);
844
845		memcpy(mptr, cmd, 10);
846		mptr += 4;
847		*mptr++ = cpu_to_le32(blk_rq_bytes(req));
848	} else
849#endif
850	{
851		msg->u.head[1] = cpu_to_le32(cmd | HOST_TID << 12 | tid);
852		*mptr++ = cpu_to_le32(ctl_flags);
853		*mptr++ = cpu_to_le32(blk_rq_bytes(req));
854		*mptr++ =
855		    cpu_to_le32((u32) (blk_rq_pos(req) << KERNEL_SECTOR_SHIFT));
856		*mptr++ =
857		    cpu_to_le32(blk_rq_pos(req) >> (32 - KERNEL_SECTOR_SHIFT));
858	}
859
860	if (!i2o_block_sglist_alloc(c, ireq, &mptr)) {
861		rc = -ENOMEM;
862		goto context_remove;
863	}
864
865	msg->u.head[0] =
866	    cpu_to_le32(I2O_MESSAGE_SIZE(mptr - &msg->u.head[0]) | sgl_offset);
867
868	list_add_tail(&ireq->queue, &dev->open_queue);
869	dev->open_queue_depth++;
870
871	i2o_msg_post(c, msg);
872
873	return 0;
874
875      context_remove:
876	i2o_cntxt_list_remove(c, req);
877
878      nop_msg:
879	i2o_msg_nop(c, msg);
880
881      exit:
882	return rc;
883};
884
885/**
886 *	i2o_block_request_fn - request queue handling function
887 *	@q: request queue from which the request could be fetched
888 *
889 *	Takes the next request from the queue, transfers it and if no error
890 *	occurs dequeue it from the queue. On arrival of the reply the message
891 *	will be processed further. If an error occurs requeue the request.
892 */
893static void i2o_block_request_fn(struct request_queue *q)
894{
895	struct request *req;
896
897	while (!blk_queue_plugged(q)) {
898		req = blk_peek_request(q);
899		if (!req)
900			break;
901
902		if (req->cmd_type == REQ_TYPE_FS) {
903			struct i2o_block_delayed_request *dreq;
904			struct i2o_block_request *ireq = req->special;
905			unsigned int queue_depth;
906
907			queue_depth = ireq->i2o_blk_dev->open_queue_depth;
908
909			if (queue_depth < I2O_BLOCK_MAX_OPEN_REQUESTS) {
910				if (!i2o_block_transfer(req)) {
911					blk_start_request(req);
912					continue;
913				} else
914					osm_info("transfer error\n");
915			}
916
917			if (queue_depth)
918				break;
919
920			/* stop the queue and retry later */
921			dreq = kmalloc(sizeof(*dreq), GFP_ATOMIC);
922			if (!dreq)
923				continue;
924
925			dreq->queue = q;
926			INIT_DELAYED_WORK(&dreq->work,
927					  i2o_block_delayed_request_fn);
928
929			if (!queue_delayed_work(i2o_block_driver.event_queue,
930						&dreq->work,
931						I2O_BLOCK_RETRY_TIME))
932				kfree(dreq);
933			else {
934				blk_stop_queue(q);
935				break;
936			}
937		} else {
938			blk_start_request(req);
939			__blk_end_request_all(req, -EIO);
940		}
941	}
942};
943
944/* I2O Block device operations definition */
945static const struct block_device_operations i2o_block_fops = {
946	.owner = THIS_MODULE,
947	.open = i2o_block_open,
948	.release = i2o_block_release,
949	.ioctl = i2o_block_ioctl,
950	.compat_ioctl = i2o_block_ioctl,
951	.getgeo = i2o_block_getgeo,
952	.media_changed = i2o_block_media_changed
953};
954
955/**
956 *	i2o_block_device_alloc - Allocate memory for a I2O Block device
957 *
958 *	Allocate memory for the i2o_block_device struct, gendisk and request
959 *	queue and initialize them as far as no additional information is needed.
960 *
961 *	Returns a pointer to the allocated I2O Block device on success or a
962 *	negative error code on failure.
963 */
964static struct i2o_block_device *i2o_block_device_alloc(void)
965{
966	struct i2o_block_device *dev;
967	struct gendisk *gd;
968	struct request_queue *queue;
969	int rc;
970
971	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
972	if (!dev) {
973		osm_err("Insufficient memory to allocate I2O Block disk.\n");
974		rc = -ENOMEM;
975		goto exit;
976	}
977
978	INIT_LIST_HEAD(&dev->open_queue);
979	spin_lock_init(&dev->lock);
980	dev->rcache = CACHE_PREFETCH;
981	dev->wcache = CACHE_WRITEBACK;
982
983	/* allocate a gendisk with 16 partitions */
984	gd = alloc_disk(16);
985	if (!gd) {
986		osm_err("Insufficient memory to allocate gendisk.\n");
987		rc = -ENOMEM;
988		goto cleanup_dev;
989	}
990
991	/* initialize the request queue */
992	queue = blk_init_queue(i2o_block_request_fn, &dev->lock);
993	if (!queue) {
994		osm_err("Insufficient memory to allocate request queue.\n");
995		rc = -ENOMEM;
996		goto cleanup_queue;
997	}
998
999	blk_queue_prep_rq(queue, i2o_block_prep_req_fn);
1000
1001	gd->major = I2O_MAJOR;
1002	gd->queue = queue;
1003	gd->fops = &i2o_block_fops;
1004	gd->private_data = dev;
1005
1006	dev->gd = gd;
1007
1008	return dev;
1009
1010      cleanup_queue:
1011	put_disk(gd);
1012
1013      cleanup_dev:
1014	kfree(dev);
1015
1016      exit:
1017	return ERR_PTR(rc);
1018};
1019
1020/**
1021 *	i2o_block_probe - verify if dev is a I2O Block device and install it
1022 *	@dev: device to verify if it is a I2O Block device
1023 *
1024 *	We only verify if the user_tid of the device is 0xfff and then install
1025 *	the device. Otherwise it is used by some other device (e. g. RAID).
1026 *
1027 *	Returns 0 on success or negative error code on failure.
1028 */
1029static int i2o_block_probe(struct device *dev)
1030{
1031	struct i2o_device *i2o_dev = to_i2o_device(dev);
1032	struct i2o_controller *c = i2o_dev->iop;
1033	struct i2o_block_device *i2o_blk_dev;
1034	struct gendisk *gd;
1035	struct request_queue *queue;
1036	static int unit = 0;
1037	int rc;
1038	u64 size;
1039	u32 blocksize;
1040	u16 body_size = 4;
1041	u16 power;
1042	unsigned short max_sectors;
1043
1044#ifdef CONFIG_I2O_EXT_ADAPTEC
1045	if (c->adaptec)
1046		body_size = 8;
1047#endif
1048
1049	if (c->limit_sectors)
1050		max_sectors = I2O_MAX_SECTORS_LIMITED;
1051	else
1052		max_sectors = I2O_MAX_SECTORS;
1053
1054	/* skip devices which are used by IOP */
1055	if (i2o_dev->lct_data.user_tid != 0xfff) {
1056		osm_debug("skipping used device %03x\n", i2o_dev->lct_data.tid);
1057		return -ENODEV;
1058	}
1059
1060	if (i2o_device_claim(i2o_dev)) {
1061		osm_warn("Unable to claim device. Installation aborted\n");
1062		rc = -EFAULT;
1063		goto exit;
1064	}
1065
1066	i2o_blk_dev = i2o_block_device_alloc();
1067	if (IS_ERR(i2o_blk_dev)) {
1068		osm_err("could not alloc a new I2O block device");
1069		rc = PTR_ERR(i2o_blk_dev);
1070		goto claim_release;
1071	}
1072
1073	i2o_blk_dev->i2o_dev = i2o_dev;
1074	dev_set_drvdata(dev, i2o_blk_dev);
1075
1076	/* setup gendisk */
1077	gd = i2o_blk_dev->gd;
1078	gd->first_minor = unit << 4;
1079	sprintf(gd->disk_name, "i2o/hd%c", 'a' + unit);
1080	gd->driverfs_dev = &i2o_dev->device;
1081
1082	/* setup request queue */
1083	queue = gd->queue;
1084	queue->queuedata = i2o_blk_dev;
1085
1086	blk_queue_max_hw_sectors(queue, max_sectors);
1087	blk_queue_max_segments(queue, i2o_sg_tablesize(c, body_size));
1088
1089	osm_debug("max sectors = %d\n", queue->max_sectors);
1090	osm_debug("phys segments = %d\n", queue->max_phys_segments);
1091	osm_debug("max hw segments = %d\n", queue->max_hw_segments);
1092
1093	/*
1094	 *      Ask for the current media data. If that isn't supported
1095	 *      then we ask for the device capacity data
1096	 */
1097	if (!i2o_parm_field_get(i2o_dev, 0x0004, 1, &blocksize, 4) ||
1098	    !i2o_parm_field_get(i2o_dev, 0x0000, 3, &blocksize, 4)) {
1099		blk_queue_logical_block_size(queue, le32_to_cpu(blocksize));
1100	} else
1101		osm_warn("unable to get blocksize of %s\n", gd->disk_name);
1102
1103	if (!i2o_parm_field_get(i2o_dev, 0x0004, 0, &size, 8) ||
1104	    !i2o_parm_field_get(i2o_dev, 0x0000, 4, &size, 8)) {
1105		set_capacity(gd, le64_to_cpu(size) >> KERNEL_SECTOR_SHIFT);
1106	} else
1107		osm_warn("could not get size of %s\n", gd->disk_name);
1108
1109	if (!i2o_parm_field_get(i2o_dev, 0x0000, 2, &power, 2))
1110		i2o_blk_dev->power = power;
1111
1112	i2o_event_register(i2o_dev, &i2o_block_driver, 0, 0xffffffff);
1113
1114	add_disk(gd);
1115
1116	unit++;
1117
1118	osm_info("device added (TID: %03x): %s\n", i2o_dev->lct_data.tid,
1119		 i2o_blk_dev->gd->disk_name);
1120
1121	return 0;
1122
1123      claim_release:
1124	i2o_device_claim_release(i2o_dev);
1125
1126      exit:
1127	return rc;
1128};
1129
1130/* Block OSM driver struct */
1131static struct i2o_driver i2o_block_driver = {
1132	.name = OSM_NAME,
1133	.event = i2o_block_event,
1134	.reply = i2o_block_reply,
1135	.classes = i2o_block_class_id,
1136	.driver = {
1137		   .probe = i2o_block_probe,
1138		   .remove = i2o_block_remove,
1139		   },
1140};
1141
1142/**
1143 *	i2o_block_init - Block OSM initialization function
1144 *
1145 *	Allocate the slab and mempool for request structs, registers i2o_block
1146 *	block device and finally register the Block OSM in the I2O core.
1147 *
1148 *	Returns 0 on success or negative error code on failure.
1149 */
1150static int __init i2o_block_init(void)
1151{
1152	int rc;
1153	int size;
1154
1155	printk(KERN_INFO OSM_DESCRIPTION " v" OSM_VERSION "\n");
1156
1157	/* Allocate request mempool and slab */
1158	size = sizeof(struct i2o_block_request);
1159	i2o_blk_req_pool.slab = kmem_cache_create("i2o_block_req", size, 0,
1160						  SLAB_HWCACHE_ALIGN, NULL);
1161	if (!i2o_blk_req_pool.slab) {
1162		osm_err("can't init request slab\n");
1163		rc = -ENOMEM;
1164		goto exit;
1165	}
1166
1167	i2o_blk_req_pool.pool =
1168		mempool_create_slab_pool(I2O_BLOCK_REQ_MEMPOOL_SIZE,
1169					 i2o_blk_req_pool.slab);
1170	if (!i2o_blk_req_pool.pool) {
1171		osm_err("can't init request mempool\n");
1172		rc = -ENOMEM;
1173		goto free_slab;
1174	}
1175
1176	/* Register the block device interfaces */
1177	rc = register_blkdev(I2O_MAJOR, "i2o_block");
1178	if (rc) {
1179		osm_err("unable to register block device\n");
1180		goto free_mempool;
1181	}
1182#ifdef MODULE
1183	osm_info("registered device at major %d\n", I2O_MAJOR);
1184#endif
1185
1186	/* Register Block OSM into I2O core */
1187	rc = i2o_driver_register(&i2o_block_driver);
1188	if (rc) {
1189		osm_err("Could not register Block driver\n");
1190		goto unregister_blkdev;
1191	}
1192
1193	return 0;
1194
1195      unregister_blkdev:
1196	unregister_blkdev(I2O_MAJOR, "i2o_block");
1197
1198      free_mempool:
1199	mempool_destroy(i2o_blk_req_pool.pool);
1200
1201      free_slab:
1202	kmem_cache_destroy(i2o_blk_req_pool.slab);
1203
1204      exit:
1205	return rc;
1206};
1207
1208/**
1209 *	i2o_block_exit - Block OSM exit function
1210 *
1211 *	Unregisters Block OSM from I2O core, unregisters i2o_block block device
1212 *	and frees the mempool and slab.
1213 */
1214static void __exit i2o_block_exit(void)
1215{
1216	/* Unregister I2O Block OSM from I2O core */
1217	i2o_driver_unregister(&i2o_block_driver);
1218
1219	/* Unregister block device */
1220	unregister_blkdev(I2O_MAJOR, "i2o_block");
1221
1222	/* Free request mempool and slab */
1223	mempool_destroy(i2o_blk_req_pool.pool);
1224	kmem_cache_destroy(i2o_blk_req_pool.slab);
1225};
1226
1227MODULE_AUTHOR("Red Hat");
1228MODULE_LICENSE("GPL");
1229MODULE_DESCRIPTION(OSM_DESCRIPTION);
1230MODULE_VERSION(OSM_VERSION);
1231
1232module_init(i2o_block_init);
1233module_exit(i2o_block_exit);
1234