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/mutex.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 DEFINE_MUTEX(i2o_block_mutex);
73static struct i2o_driver i2o_block_driver;
74
75/* global Block OSM request mempool */
76static struct i2o_block_mempool i2o_blk_req_pool;
77
78/* Block OSM class handling definition */
79static struct i2o_class_id i2o_block_class_id[] = {
80	{I2O_CLASS_RANDOM_BLOCK_STORAGE},
81	{I2O_CLASS_END}
82};
83
84/**
85 *	i2o_block_device_free - free the memory of the I2O Block device
86 *	@dev: I2O Block device, which should be cleaned up
87 *
88 *	Frees the request queue, gendisk and the i2o_block_device structure.
89 */
90static void i2o_block_device_free(struct i2o_block_device *dev)
91{
92	blk_cleanup_queue(dev->gd->queue);
93
94	put_disk(dev->gd);
95
96	kfree(dev);
97};
98
99/**
100 *	i2o_block_remove - remove the I2O Block device from the system again
101 *	@dev: I2O Block device which should be removed
102 *
103 *	Remove gendisk from system and free all allocated memory.
104 *
105 *	Always returns 0.
106 */
107static int i2o_block_remove(struct device *dev)
108{
109	struct i2o_device *i2o_dev = to_i2o_device(dev);
110	struct i2o_block_device *i2o_blk_dev = dev_get_drvdata(dev);
111
112	osm_info("device removed (TID: %03x): %s\n", i2o_dev->lct_data.tid,
113		 i2o_blk_dev->gd->disk_name);
114
115	i2o_event_register(i2o_dev, &i2o_block_driver, 0, 0);
116
117	del_gendisk(i2o_blk_dev->gd);
118
119	dev_set_drvdata(dev, NULL);
120
121	i2o_device_claim_release(i2o_dev);
122
123	i2o_block_device_free(i2o_blk_dev);
124
125	return 0;
126};
127
128/**
129 *	i2o_block_device flush - Flush all dirty data of I2O device dev
130 *	@dev: I2O device which should be flushed
131 *
132 *	Flushes all dirty data on device dev.
133 *
134 *	Returns 0 on success or negative error code on failure.
135 */
136static int i2o_block_device_flush(struct i2o_device *dev)
137{
138	struct i2o_message *msg;
139
140	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
141	if (IS_ERR(msg))
142		return PTR_ERR(msg);
143
144	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
145	msg->u.head[1] =
146	    cpu_to_le32(I2O_CMD_BLOCK_CFLUSH << 24 | HOST_TID << 12 | dev->
147			lct_data.tid);
148	msg->body[0] = cpu_to_le32(60 << 16);
149	osm_debug("Flushing...\n");
150
151	return i2o_msg_post_wait(dev->iop, msg, 60);
152};
153
154/**
155 *	i2o_block_device_mount - Mount (load) the media of device dev
156 *	@dev: I2O device which should receive the mount request
157 *	@media_id: Media Identifier
158 *
159 *	Load a media into drive. Identifier should be set to -1, because the
160 *	spec does not support any other value.
161 *
162 *	Returns 0 on success or negative error code on failure.
163 */
164static int i2o_block_device_mount(struct i2o_device *dev, u32 media_id)
165{
166	struct i2o_message *msg;
167
168	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
169	if (IS_ERR(msg))
170		return PTR_ERR(msg);
171
172	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
173	msg->u.head[1] =
174	    cpu_to_le32(I2O_CMD_BLOCK_MMOUNT << 24 | HOST_TID << 12 | dev->
175			lct_data.tid);
176	msg->body[0] = cpu_to_le32(-1);
177	msg->body[1] = cpu_to_le32(0x00000000);
178	osm_debug("Mounting...\n");
179
180	return i2o_msg_post_wait(dev->iop, msg, 2);
181};
182
183/**
184 *	i2o_block_device_lock - Locks the media of device dev
185 *	@dev: I2O device which should receive the lock request
186 *	@media_id: Media Identifier
187 *
188 *	Lock media of device dev to prevent removal. The media identifier
189 *	should be set to -1, because the spec does not support any other value.
190 *
191 *	Returns 0 on success or negative error code on failure.
192 */
193static int i2o_block_device_lock(struct i2o_device *dev, u32 media_id)
194{
195	struct i2o_message *msg;
196
197	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
198	if (IS_ERR(msg))
199		return PTR_ERR(msg);
200
201	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
202	msg->u.head[1] =
203	    cpu_to_le32(I2O_CMD_BLOCK_MLOCK << 24 | HOST_TID << 12 | dev->
204			lct_data.tid);
205	msg->body[0] = cpu_to_le32(-1);
206	osm_debug("Locking...\n");
207
208	return i2o_msg_post_wait(dev->iop, msg, 2);
209};
210
211/**
212 *	i2o_block_device_unlock - Unlocks the media of device dev
213 *	@dev: I2O device which should receive the unlocked request
214 *	@media_id: Media Identifier
215 *
216 *	Unlocks the media in device dev. The media identifier should be set to
217 *	-1, because the spec does not support any other value.
218 *
219 *	Returns 0 on success or negative error code on failure.
220 */
221static int i2o_block_device_unlock(struct i2o_device *dev, u32 media_id)
222{
223	struct i2o_message *msg;
224
225	msg = i2o_msg_get_wait(dev->iop, I2O_TIMEOUT_MESSAGE_GET);
226	if (IS_ERR(msg))
227		return PTR_ERR(msg);
228
229	msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
230	msg->u.head[1] =
231	    cpu_to_le32(I2O_CMD_BLOCK_MUNLOCK << 24 | HOST_TID << 12 | dev->
232			lct_data.tid);
233	msg->body[0] = cpu_to_le32(media_id);
234	osm_debug("Unlocking...\n");
235
236	return i2o_msg_post_wait(dev->iop, msg, 2);
237};
238
239/**
240 *	i2o_block_device_power - Power management for device dev
241 *	@dev: I2O device which should receive the power management request
242 *	@op: Operation to send
243 *
244 *	Send a power management request to the device dev.
245 *
246 *	Returns 0 on success or negative error code on failure.
247 */
248static int i2o_block_device_power(struct i2o_block_device *dev, u8 op)
249{
250	struct i2o_device *i2o_dev = dev->i2o_dev;
251	struct i2o_controller *c = i2o_dev->iop;
252	struct i2o_message *msg;
253	int rc;
254
255	msg = i2o_msg_get_wait(c, I2O_TIMEOUT_MESSAGE_GET);
256	if (IS_ERR(msg))
257		return PTR_ERR(msg);
258
259	msg->u.head[0] = cpu_to_le32(FOUR_WORD_MSG_SIZE | SGL_OFFSET_0);
260	msg->u.head[1] =
261	    cpu_to_le32(I2O_CMD_BLOCK_POWER << 24 | HOST_TID << 12 | i2o_dev->
262			lct_data.tid);
263	msg->body[0] = cpu_to_le32(op << 24);
264	osm_debug("Power...\n");
265
266	rc = i2o_msg_post_wait(c, msg, 60);
267	if (!rc)
268		dev->power = op;
269
270	return rc;
271};
272
273/**
274 *	i2o_block_request_alloc - Allocate an I2O block request struct
275 *
276 *	Allocates an I2O block request struct and initialize the list.
277 *
278 *	Returns a i2o_block_request pointer on success or negative error code
279 *	on failure.
280 */
281static inline struct i2o_block_request *i2o_block_request_alloc(void)
282{
283	struct i2o_block_request *ireq;
284
285	ireq = mempool_alloc(i2o_blk_req_pool.pool, GFP_ATOMIC);
286	if (!ireq)
287		return ERR_PTR(-ENOMEM);
288
289	INIT_LIST_HEAD(&ireq->queue);
290	sg_init_table(ireq->sg_table, I2O_MAX_PHYS_SEGMENTS);
291
292	return ireq;
293};
294
295/**
296 *	i2o_block_request_free - Frees a I2O block request
297 *	@ireq: I2O block request which should be freed
298 *
299 *	Frees the allocated memory (give it back to the request mempool).
300 */
301static inline void i2o_block_request_free(struct i2o_block_request *ireq)
302{
303	mempool_free(ireq, i2o_blk_req_pool.pool);
304};
305
306/**
307 *	i2o_block_sglist_alloc - Allocate the SG list and map it
308 *	@c: I2O controller to which the request belongs
309 *	@ireq: I2O block request
310 *	@mptr: message body pointer
311 *
312 *	Builds the SG list and map it to be accessible by the controller.
313 *
314 *	Returns 0 on failure or 1 on success.
315 */
316static inline int i2o_block_sglist_alloc(struct i2o_controller *c,
317					 struct i2o_block_request *ireq,
318					 u32 ** mptr)
319{
320	int nents;
321	enum dma_data_direction direction;
322
323	ireq->dev = &c->pdev->dev;
324	nents = blk_rq_map_sg(ireq->req->q, ireq->req, ireq->sg_table);
325
326	if (rq_data_dir(ireq->req) == READ)
327		direction = PCI_DMA_FROMDEVICE;
328	else
329		direction = PCI_DMA_TODEVICE;
330
331	ireq->sg_nents = nents;
332
333	return i2o_dma_map_sg(c, ireq->sg_table, nents, direction, mptr);
334};
335
336/**
337 *	i2o_block_sglist_free - Frees the SG list
338 *	@ireq: I2O block request from which the SG should be freed
339 *
340 *	Frees the SG list from the I2O block request.
341 */
342static inline void i2o_block_sglist_free(struct i2o_block_request *ireq)
343{
344	enum dma_data_direction direction;
345
346	if (rq_data_dir(ireq->req) == READ)
347		direction = PCI_DMA_FROMDEVICE;
348	else
349		direction = PCI_DMA_TODEVICE;
350
351	dma_unmap_sg(ireq->dev, ireq->sg_table, ireq->sg_nents, direction);
352};
353
354/**
355 *	i2o_block_prep_req_fn - Allocates I2O block device specific struct
356 *	@q: request queue for the request
357 *	@req: the request to prepare
358 *
359 *	Allocate the necessary i2o_block_request struct and connect it to
360 *	the request. This is needed that we not lose the SG list later on.
361 *
362 *	Returns BLKPREP_OK on success or BLKPREP_DEFER on failure.
363 */
364static int i2o_block_prep_req_fn(struct request_queue *q, struct request *req)
365{
366	struct i2o_block_device *i2o_blk_dev = q->queuedata;
367	struct i2o_block_request *ireq;
368
369	if (unlikely(!i2o_blk_dev)) {
370		osm_err("block device already removed\n");
371		return BLKPREP_KILL;
372	}
373
374	/* connect the i2o_block_request to the request */
375	if (!req->special) {
376		ireq = i2o_block_request_alloc();
377		if (IS_ERR(ireq)) {
378			osm_debug("unable to allocate i2o_block_request!\n");
379			return BLKPREP_DEFER;
380		}
381
382		ireq->i2o_blk_dev = i2o_blk_dev;
383		req->special = ireq;
384		ireq->req = req;
385	}
386	/* do not come back here */
387	req->cmd_flags |= REQ_DONTPREP;
388
389	return BLKPREP_OK;
390};
391
392/**
393 *	i2o_block_delayed_request_fn - delayed request queue function
394 *	@work: the delayed request with the queue to start
395 *
396 *	If the request queue is stopped for a disk, and there is no open
397 *	request, a new event is created, which calls this function to start
398 *	the queue after I2O_BLOCK_REQUEST_TIME. Otherwise the queue will never
399 *	be started again.
400 */
401static void i2o_block_delayed_request_fn(struct work_struct *work)
402{
403	struct i2o_block_delayed_request *dreq =
404		container_of(work, struct i2o_block_delayed_request,
405			     work.work);
406	struct request_queue *q = dreq->queue;
407	unsigned long flags;
408
409	spin_lock_irqsave(q->queue_lock, flags);
410	blk_start_queue(q);
411	spin_unlock_irqrestore(q->queue_lock, flags);
412	kfree(dreq);
413};
414
415/**
416 *	i2o_block_end_request - Post-processing of completed commands
417 *	@req: request which should be completed
418 *	@error: 0 for success, < 0 for error
419 *	@nr_bytes: number of bytes to complete
420 *
421 *	Mark the request as complete. The lock must not be held when entering.
422 *
423 */
424static void i2o_block_end_request(struct request *req, int error,
425				  int nr_bytes)
426{
427	struct i2o_block_request *ireq = req->special;
428	struct i2o_block_device *dev = ireq->i2o_blk_dev;
429	struct request_queue *q = req->q;
430	unsigned long flags;
431
432	if (blk_end_request(req, error, nr_bytes))
433		if (error)
434			blk_end_request_all(req, -EIO);
435
436	spin_lock_irqsave(q->queue_lock, flags);
437
438	if (likely(dev)) {
439		dev->open_queue_depth--;
440		list_del(&ireq->queue);
441	}
442
443	blk_start_queue(q);
444
445	spin_unlock_irqrestore(q->queue_lock, flags);
446
447	i2o_block_sglist_free(ireq);
448	i2o_block_request_free(ireq);
449};
450
451/**
452 *	i2o_block_reply - Block OSM reply handler.
453 *	@c: I2O controller from which the message arrives
454 *	@m: message id of reply
455 *	@msg: the actual I2O message reply
456 *
457 *	This function gets all the message replies.
458 *
459 */
460static int i2o_block_reply(struct i2o_controller *c, u32 m,
461			   struct i2o_message *msg)
462{
463	struct request *req;
464	int error = 0;
465
466	req = i2o_cntxt_list_get(c, le32_to_cpu(msg->u.s.tcntxt));
467	if (unlikely(!req)) {
468		osm_err("NULL reply received!\n");
469		return -1;
470	}
471
472	/*
473	 *      Lets see what is cooking. We stuffed the
474	 *      request in the context.
475	 */
476
477	if ((le32_to_cpu(msg->body[0]) >> 24) != 0) {
478		u32 status = le32_to_cpu(msg->body[0]);
479		/*
480		 *      Device not ready means two things. One is that the
481		 *      the thing went offline (but not a removal media)
482		 *
483		 *      The second is that you have a SuperTrak 100 and the
484		 *      firmware got constipated. Unlike standard i2o card
485		 *      setups the supertrak returns an error rather than
486		 *      blocking for the timeout in these cases.
487		 *
488		 *      Don't stick a supertrak100 into cache aggressive modes
489		 */
490
491		osm_err("TID %03x error status: 0x%02x, detailed status: "
492			"0x%04x\n", (le32_to_cpu(msg->u.head[1]) >> 12 & 0xfff),
493			status >> 24, status & 0xffff);
494
495		req->errors++;
496
497		error = -EIO;
498	}
499
500	i2o_block_end_request(req, error, le32_to_cpu(msg->body[1]));
501
502	return 1;
503};
504
505static void i2o_block_event(struct work_struct *work)
506{
507	struct i2o_event *evt = container_of(work, struct i2o_event, work);
508	osm_debug("event received\n");
509	kfree(evt);
510};
511
512/*
513 *	SCSI-CAM for ioctl geometry mapping
514 *	Duplicated with SCSI - this should be moved into somewhere common
515 *	perhaps genhd ?
516 *
517 * LBA -> CHS mapping table taken from:
518 *
519 * "Incorporating the I2O Architecture into BIOS for Intel Architecture
520 *  Platforms"
521 *
522 * This is an I2O document that is only available to I2O members,
523 * not developers.
524 *
525 * From my understanding, this is how all the I2O cards do this
526 *
527 * Disk Size      | Sectors | Heads | Cylinders
528 * ---------------+---------+-------+-------------------
529 * 1 < X <= 528M  | 63      | 16    | X/(63 * 16 * 512)
530 * 528M < X <= 1G | 63      | 32    | X/(63 * 32 * 512)
531 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
532 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
533 *
534 */
535#define	BLOCK_SIZE_528M		1081344
536#define	BLOCK_SIZE_1G		2097152
537#define	BLOCK_SIZE_21G		4403200
538#define	BLOCK_SIZE_42G		8806400
539#define	BLOCK_SIZE_84G		17612800
540
541static void i2o_block_biosparam(unsigned long capacity, unsigned short *cyls,
542				unsigned char *hds, unsigned char *secs)
543{
544	unsigned long heads, sectors, cylinders;
545
546	sectors = 63L;		/* Maximize sectors per track */
547	if (capacity <= BLOCK_SIZE_528M)
548		heads = 16;
549	else if (capacity <= BLOCK_SIZE_1G)
550		heads = 32;
551	else if (capacity <= BLOCK_SIZE_21G)
552		heads = 64;
553	else if (capacity <= BLOCK_SIZE_42G)
554		heads = 128;
555	else
556		heads = 255;
557
558	cylinders = (unsigned long)capacity / (heads * sectors);
559
560	*cyls = (unsigned short)cylinders;	/* Stuff return values */
561	*secs = (unsigned char)sectors;
562	*hds = (unsigned char)heads;
563}
564
565/**
566 *	i2o_block_open - Open the block device
567 *	@bdev: block device being opened
568 *	@mode: file open mode
569 *
570 *	Power up the device, mount and lock the media. This function is called,
571 *	if the block device is opened for access.
572 *
573 *	Returns 0 on success or negative error code on failure.
574 */
575static int i2o_block_open(struct block_device *bdev, fmode_t mode)
576{
577	struct i2o_block_device *dev = bdev->bd_disk->private_data;
578
579	if (!dev->i2o_dev)
580		return -ENODEV;
581
582	mutex_lock(&i2o_block_mutex);
583	if (dev->power > 0x1f)
584		i2o_block_device_power(dev, 0x02);
585
586	i2o_block_device_mount(dev->i2o_dev, -1);
587
588	i2o_block_device_lock(dev->i2o_dev, -1);
589
590	osm_debug("Ready.\n");
591	mutex_unlock(&i2o_block_mutex);
592
593	return 0;
594};
595
596/**
597 *	i2o_block_release - Release the I2O block device
598 *	@disk: gendisk device being released
599 *	@mode: file open mode
600 *
601 *	Unlock and unmount the media, and power down the device. Gets called if
602 *	the block device is closed.
603 *
604 *	Returns 0 on success or negative error code on failure.
605 */
606static int i2o_block_release(struct gendisk *disk, fmode_t mode)
607{
608	struct i2o_block_device *dev = disk->private_data;
609	u8 operation;
610
611	/*
612	 * This is to deail with the case of an application
613	 * opening a device and then the device disappears while
614	 * it's in use, and then the application tries to release
615	 * it.  ex: Unmounting a deleted RAID volume at reboot.
616	 * If we send messages, it will just cause FAILs since
617	 * the TID no longer exists.
618	 */
619	if (!dev->i2o_dev)
620		return 0;
621
622	mutex_lock(&i2o_block_mutex);
623	i2o_block_device_flush(dev->i2o_dev);
624
625	i2o_block_device_unlock(dev->i2o_dev, -1);
626
627	if (dev->flags & (1 << 3 | 1 << 4))	/* Removable */
628		operation = 0x21;
629	else
630		operation = 0x24;
631
632	i2o_block_device_power(dev, operation);
633	mutex_unlock(&i2o_block_mutex);
634
635	return 0;
636}
637
638static int i2o_block_getgeo(struct block_device *bdev, struct hd_geometry *geo)
639{
640	i2o_block_biosparam(get_capacity(bdev->bd_disk),
641			    &geo->cylinders, &geo->heads, &geo->sectors);
642	return 0;
643}
644
645/**
646 *	i2o_block_ioctl - Issue device specific ioctl calls.
647 *	@bdev: block device being opened
648 *	@mode: file open mode
649 *	@cmd: ioctl command
650 *	@arg: arg
651 *
652 *	Handles ioctl request for the block device.
653 *
654 *	Return 0 on success or negative error on failure.
655 */
656static int i2o_block_ioctl(struct block_device *bdev, fmode_t mode,
657			   unsigned int cmd, unsigned long arg)
658{
659	struct gendisk *disk = bdev->bd_disk;
660	struct i2o_block_device *dev = disk->private_data;
661	int ret = -ENOTTY;
662
663	/* Anyone capable of this syscall can do *real bad* things */
664
665	if (!capable(CAP_SYS_ADMIN))
666		return -EPERM;
667
668	mutex_lock(&i2o_block_mutex);
669	switch (cmd) {
670	case BLKI2OGRSTRAT:
671		ret = put_user(dev->rcache, (int __user *)arg);
672		break;
673	case BLKI2OGWSTRAT:
674		ret = put_user(dev->wcache, (int __user *)arg);
675		break;
676	case BLKI2OSRSTRAT:
677		ret = -EINVAL;
678		if (arg < 0 || arg > CACHE_SMARTFETCH)
679			break;
680		dev->rcache = arg;
681		ret = 0;
682		break;
683	case BLKI2OSWSTRAT:
684		ret = -EINVAL;
685		if (arg != 0
686		    && (arg < CACHE_WRITETHROUGH || arg > CACHE_SMARTBACK))
687			break;
688		dev->wcache = arg;
689		ret = 0;
690		break;
691	}
692	mutex_unlock(&i2o_block_mutex);
693
694	return ret;
695};
696
697/**
698 *	i2o_block_check_events - Have we seen a media change?
699 *	@disk: gendisk which should be verified
700 *	@clearing: events being cleared
701 *
702 *	Verifies if the media has changed.
703 *
704 *	Returns 1 if the media was changed or 0 otherwise.
705 */
706static unsigned int i2o_block_check_events(struct gendisk *disk,
707					   unsigned int clearing)
708{
709	struct i2o_block_device *p = disk->private_data;
710
711	if (p->media_change_flag) {
712		p->media_change_flag = 0;
713		return DISK_EVENT_MEDIA_CHANGE;
714	}
715	return 0;
716}
717
718/**
719 *	i2o_block_transfer - Transfer a request to/from the I2O controller
720 *	@req: the request which should be transferred
721 *
722 *	This function converts the request into a I2O message. The necessary
723 *	DMA buffers are allocated and after everything is setup post the message
724 *	to the I2O controller. No cleanup is done by this function. It is done
725 *	on the interrupt side when the reply arrives.
726 *
727 *	Return 0 on success or negative error code on failure.
728 */
729static int i2o_block_transfer(struct request *req)
730{
731	struct i2o_block_device *dev = req->rq_disk->private_data;
732	struct i2o_controller *c;
733	u32 tid;
734	struct i2o_message *msg;
735	u32 *mptr;
736	struct i2o_block_request *ireq = req->special;
737	u32 tcntxt;
738	u32 sgl_offset = SGL_OFFSET_8;
739	u32 ctl_flags = 0x00000000;
740	int rc;
741	u32 cmd;
742
743	if (unlikely(!dev->i2o_dev)) {
744		osm_err("transfer to removed drive\n");
745		rc = -ENODEV;
746		goto exit;
747	}
748
749	tid = dev->i2o_dev->lct_data.tid;
750	c = dev->i2o_dev->iop;
751
752	msg = i2o_msg_get(c);
753	if (IS_ERR(msg)) {
754		rc = PTR_ERR(msg);
755		goto exit;
756	}
757
758	tcntxt = i2o_cntxt_list_add(c, req);
759	if (!tcntxt) {
760		rc = -ENOMEM;
761		goto nop_msg;
762	}
763
764	msg->u.s.icntxt = cpu_to_le32(i2o_block_driver.context);
765	msg->u.s.tcntxt = cpu_to_le32(tcntxt);
766
767	mptr = &msg->body[0];
768
769	if (rq_data_dir(req) == READ) {
770		cmd = I2O_CMD_BLOCK_READ << 24;
771
772		switch (dev->rcache) {
773		case CACHE_PREFETCH:
774			ctl_flags = 0x201F0008;
775			break;
776
777		case CACHE_SMARTFETCH:
778			if (blk_rq_sectors(req) > 16)
779				ctl_flags = 0x201F0008;
780			else
781				ctl_flags = 0x001F0000;
782			break;
783
784		default:
785			break;
786		}
787	} else {
788		cmd = I2O_CMD_BLOCK_WRITE << 24;
789
790		switch (dev->wcache) {
791		case CACHE_WRITETHROUGH:
792			ctl_flags = 0x001F0008;
793			break;
794		case CACHE_WRITEBACK:
795			ctl_flags = 0x001F0010;
796			break;
797		case CACHE_SMARTBACK:
798			if (blk_rq_sectors(req) > 16)
799				ctl_flags = 0x001F0004;
800			else
801				ctl_flags = 0x001F0010;
802			break;
803		case CACHE_SMARTTHROUGH:
804			if (blk_rq_sectors(req) > 16)
805				ctl_flags = 0x001F0004;
806			else
807				ctl_flags = 0x001F0010;
808		default:
809			break;
810		}
811	}
812
813#ifdef CONFIG_I2O_EXT_ADAPTEC
814	if (c->adaptec) {
815		u8 cmd[10];
816		u32 scsi_flags;
817		u16 hwsec;
818
819		hwsec = queue_logical_block_size(req->q) >> KERNEL_SECTOR_SHIFT;
820		memset(cmd, 0, 10);
821
822		sgl_offset = SGL_OFFSET_12;
823
824		msg->u.head[1] =
825		    cpu_to_le32(I2O_CMD_PRIVATE << 24 | HOST_TID << 12 | tid);
826
827		*mptr++ = cpu_to_le32(I2O_VENDOR_DPT << 16 | I2O_CMD_SCSI_EXEC);
828		*mptr++ = cpu_to_le32(tid);
829
830		/*
831		 * ENABLE_DISCONNECT
832		 * SIMPLE_TAG
833		 * RETURN_SENSE_DATA_IN_REPLY_MESSAGE_FRAME
834		 */
835		if (rq_data_dir(req) == READ) {
836			cmd[0] = READ_10;
837			scsi_flags = 0x60a0000a;
838		} else {
839			cmd[0] = WRITE_10;
840			scsi_flags = 0xa0a0000a;
841		}
842
843		*mptr++ = cpu_to_le32(scsi_flags);
844
845		*((u32 *) & cmd[2]) = cpu_to_be32(blk_rq_pos(req) * hwsec);
846		*((u16 *) & cmd[7]) = cpu_to_be16(blk_rq_sectors(req) * hwsec);
847
848		memcpy(mptr, cmd, 10);
849		mptr += 4;
850		*mptr++ = cpu_to_le32(blk_rq_bytes(req));
851	} else
852#endif
853	{
854		msg->u.head[1] = cpu_to_le32(cmd | HOST_TID << 12 | tid);
855		*mptr++ = cpu_to_le32(ctl_flags);
856		*mptr++ = cpu_to_le32(blk_rq_bytes(req));
857		*mptr++ =
858		    cpu_to_le32((u32) (blk_rq_pos(req) << KERNEL_SECTOR_SHIFT));
859		*mptr++ =
860		    cpu_to_le32(blk_rq_pos(req) >> (32 - KERNEL_SECTOR_SHIFT));
861	}
862
863	if (!i2o_block_sglist_alloc(c, ireq, &mptr)) {
864		rc = -ENOMEM;
865		goto context_remove;
866	}
867
868	msg->u.head[0] =
869	    cpu_to_le32(I2O_MESSAGE_SIZE(mptr - &msg->u.head[0]) | sgl_offset);
870
871	list_add_tail(&ireq->queue, &dev->open_queue);
872	dev->open_queue_depth++;
873
874	i2o_msg_post(c, msg);
875
876	return 0;
877
878      context_remove:
879	i2o_cntxt_list_remove(c, req);
880
881      nop_msg:
882	i2o_msg_nop(c, msg);
883
884      exit:
885	return rc;
886};
887
888/**
889 *	i2o_block_request_fn - request queue handling function
890 *	@q: request queue from which the request could be fetched
891 *
892 *	Takes the next request from the queue, transfers it and if no error
893 *	occurs dequeue it from the queue. On arrival of the reply the message
894 *	will be processed further. If an error occurs requeue the request.
895 */
896static void i2o_block_request_fn(struct request_queue *q)
897{
898	struct request *req;
899
900	while ((req = blk_peek_request(q)) != NULL) {
901		if (req->cmd_type == REQ_TYPE_FS) {
902			struct i2o_block_delayed_request *dreq;
903			struct i2o_block_request *ireq = req->special;
904			unsigned int queue_depth;
905
906			queue_depth = ireq->i2o_blk_dev->open_queue_depth;
907
908			if (queue_depth < I2O_BLOCK_MAX_OPEN_REQUESTS) {
909				if (!i2o_block_transfer(req)) {
910					blk_start_request(req);
911					continue;
912				} else
913					osm_info("transfer error\n");
914			}
915
916			if (queue_depth)
917				break;
918
919			/* stop the queue and retry later */
920			dreq = kmalloc(sizeof(*dreq), GFP_ATOMIC);
921			if (!dreq)
922				continue;
923
924			dreq->queue = q;
925			INIT_DELAYED_WORK(&dreq->work,
926					  i2o_block_delayed_request_fn);
927
928			if (!queue_delayed_work(i2o_block_driver.event_queue,
929						&dreq->work,
930						I2O_BLOCK_RETRY_TIME))
931				kfree(dreq);
932			else {
933				blk_stop_queue(q);
934				break;
935			}
936		} else {
937			blk_start_request(req);
938			__blk_end_request_all(req, -EIO);
939		}
940	}
941};
942
943/* I2O Block device operations definition */
944static const struct block_device_operations i2o_block_fops = {
945	.owner = THIS_MODULE,
946	.open = i2o_block_open,
947	.release = i2o_block_release,
948	.ioctl = i2o_block_ioctl,
949	.compat_ioctl = i2o_block_ioctl,
950	.getgeo = i2o_block_getgeo,
951	.check_events = i2o_block_check_events,
952};
953
954/**
955 *	i2o_block_device_alloc - Allocate memory for a I2O Block device
956 *
957 *	Allocate memory for the i2o_block_device struct, gendisk and request
958 *	queue and initialize them as far as no additional information is needed.
959 *
960 *	Returns a pointer to the allocated I2O Block device on success or a
961 *	negative error code on failure.
962 */
963static struct i2o_block_device *i2o_block_device_alloc(void)
964{
965	struct i2o_block_device *dev;
966	struct gendisk *gd;
967	struct request_queue *queue;
968	int rc;
969
970	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
971	if (!dev) {
972		osm_err("Insufficient memory to allocate I2O Block disk.\n");
973		rc = -ENOMEM;
974		goto exit;
975	}
976
977	INIT_LIST_HEAD(&dev->open_queue);
978	spin_lock_init(&dev->lock);
979	dev->rcache = CACHE_PREFETCH;
980	dev->wcache = CACHE_WRITEBACK;
981
982	/* allocate a gendisk with 16 partitions */
983	gd = alloc_disk(16);
984	if (!gd) {
985		osm_err("Insufficient memory to allocate gendisk.\n");
986		rc = -ENOMEM;
987		goto cleanup_dev;
988	}
989
990	/* initialize the request queue */
991	queue = blk_init_queue(i2o_block_request_fn, &dev->lock);
992	if (!queue) {
993		osm_err("Insufficient memory to allocate request queue.\n");
994		rc = -ENOMEM;
995		goto cleanup_queue;
996	}
997
998	blk_queue_prep_rq(queue, i2o_block_prep_req_fn);
999
1000	gd->major = I2O_MAJOR;
1001	gd->queue = queue;
1002	gd->fops = &i2o_block_fops;
1003	gd->private_data = dev;
1004
1005	dev->gd = gd;
1006
1007	return dev;
1008
1009      cleanup_queue:
1010	put_disk(gd);
1011
1012      cleanup_dev:
1013	kfree(dev);
1014
1015      exit:
1016	return ERR_PTR(rc);
1017};
1018
1019/**
1020 *	i2o_block_probe - verify if dev is a I2O Block device and install it
1021 *	@dev: device to verify if it is a I2O Block device
1022 *
1023 *	We only verify if the user_tid of the device is 0xfff and then install
1024 *	the device. Otherwise it is used by some other device (e. g. RAID).
1025 *
1026 *	Returns 0 on success or negative error code on failure.
1027 */
1028static int i2o_block_probe(struct device *dev)
1029{
1030	struct i2o_device *i2o_dev = to_i2o_device(dev);
1031	struct i2o_controller *c = i2o_dev->iop;
1032	struct i2o_block_device *i2o_blk_dev;
1033	struct gendisk *gd;
1034	struct request_queue *queue;
1035	static int unit = 0;
1036	int rc;
1037	u64 size;
1038	u32 blocksize;
1039	u16 body_size = 4;
1040	u16 power;
1041	unsigned short max_sectors;
1042
1043#ifdef CONFIG_I2O_EXT_ADAPTEC
1044	if (c->adaptec)
1045		body_size = 8;
1046#endif
1047
1048	if (c->limit_sectors)
1049		max_sectors = I2O_MAX_SECTORS_LIMITED;
1050	else
1051		max_sectors = I2O_MAX_SECTORS;
1052
1053	/* skip devices which are used by IOP */
1054	if (i2o_dev->lct_data.user_tid != 0xfff) {
1055		osm_debug("skipping used device %03x\n", i2o_dev->lct_data.tid);
1056		return -ENODEV;
1057	}
1058
1059	if (i2o_device_claim(i2o_dev)) {
1060		osm_warn("Unable to claim device. Installation aborted\n");
1061		rc = -EFAULT;
1062		goto exit;
1063	}
1064
1065	i2o_blk_dev = i2o_block_device_alloc();
1066	if (IS_ERR(i2o_blk_dev)) {
1067		osm_err("could not alloc a new I2O block device");
1068		rc = PTR_ERR(i2o_blk_dev);
1069		goto claim_release;
1070	}
1071
1072	i2o_blk_dev->i2o_dev = i2o_dev;
1073	dev_set_drvdata(dev, i2o_blk_dev);
1074
1075	/* setup gendisk */
1076	gd = i2o_blk_dev->gd;
1077	gd->first_minor = unit << 4;
1078	sprintf(gd->disk_name, "i2o/hd%c", 'a' + unit);
1079	gd->driverfs_dev = &i2o_dev->device;
1080
1081	/* setup request queue */
1082	queue = gd->queue;
1083	queue->queuedata = i2o_blk_dev;
1084
1085	blk_queue_max_hw_sectors(queue, max_sectors);
1086	blk_queue_max_segments(queue, i2o_sg_tablesize(c, body_size));
1087
1088	osm_debug("max sectors = %d\n", queue->max_sectors);
1089	osm_debug("phys segments = %d\n", queue->max_phys_segments);
1090	osm_debug("max hw segments = %d\n", queue->max_hw_segments);
1091
1092	/*
1093	 *      Ask for the current media data. If that isn't supported
1094	 *      then we ask for the device capacity data
1095	 */
1096	if (!i2o_parm_field_get(i2o_dev, 0x0004, 1, &blocksize, 4) ||
1097	    !i2o_parm_field_get(i2o_dev, 0x0000, 3, &blocksize, 4)) {
1098		blk_queue_logical_block_size(queue, le32_to_cpu(blocksize));
1099	} else
1100		osm_warn("unable to get blocksize of %s\n", gd->disk_name);
1101
1102	if (!i2o_parm_field_get(i2o_dev, 0x0004, 0, &size, 8) ||
1103	    !i2o_parm_field_get(i2o_dev, 0x0000, 4, &size, 8)) {
1104		set_capacity(gd, le64_to_cpu(size) >> KERNEL_SECTOR_SHIFT);
1105	} else
1106		osm_warn("could not get size of %s\n", gd->disk_name);
1107
1108	if (!i2o_parm_field_get(i2o_dev, 0x0000, 2, &power, 2))
1109		i2o_blk_dev->power = power;
1110
1111	i2o_event_register(i2o_dev, &i2o_block_driver, 0, 0xffffffff);
1112
1113	add_disk(gd);
1114
1115	unit++;
1116
1117	osm_info("device added (TID: %03x): %s\n", i2o_dev->lct_data.tid,
1118		 i2o_blk_dev->gd->disk_name);
1119
1120	return 0;
1121
1122      claim_release:
1123	i2o_device_claim_release(i2o_dev);
1124
1125      exit:
1126	return rc;
1127};
1128
1129/* Block OSM driver struct */
1130static struct i2o_driver i2o_block_driver = {
1131	.name = OSM_NAME,
1132	.event = i2o_block_event,
1133	.reply = i2o_block_reply,
1134	.classes = i2o_block_class_id,
1135	.driver = {
1136		   .probe = i2o_block_probe,
1137		   .remove = i2o_block_remove,
1138		   },
1139};
1140
1141/**
1142 *	i2o_block_init - Block OSM initialization function
1143 *
1144 *	Allocate the slab and mempool for request structs, registers i2o_block
1145 *	block device and finally register the Block OSM in the I2O core.
1146 *
1147 *	Returns 0 on success or negative error code on failure.
1148 */
1149static int __init i2o_block_init(void)
1150{
1151	int rc;
1152	int size;
1153
1154	printk(KERN_INFO OSM_DESCRIPTION " v" OSM_VERSION "\n");
1155
1156	/* Allocate request mempool and slab */
1157	size = sizeof(struct i2o_block_request);
1158	i2o_blk_req_pool.slab = kmem_cache_create("i2o_block_req", size, 0,
1159						  SLAB_HWCACHE_ALIGN, NULL);
1160	if (!i2o_blk_req_pool.slab) {
1161		osm_err("can't init request slab\n");
1162		rc = -ENOMEM;
1163		goto exit;
1164	}
1165
1166	i2o_blk_req_pool.pool =
1167		mempool_create_slab_pool(I2O_BLOCK_REQ_MEMPOOL_SIZE,
1168					 i2o_blk_req_pool.slab);
1169	if (!i2o_blk_req_pool.pool) {
1170		osm_err("can't init request mempool\n");
1171		rc = -ENOMEM;
1172		goto free_slab;
1173	}
1174
1175	/* Register the block device interfaces */
1176	rc = register_blkdev(I2O_MAJOR, "i2o_block");
1177	if (rc) {
1178		osm_err("unable to register block device\n");
1179		goto free_mempool;
1180	}
1181#ifdef MODULE
1182	osm_info("registered device at major %d\n", I2O_MAJOR);
1183#endif
1184
1185	/* Register Block OSM into I2O core */
1186	rc = i2o_driver_register(&i2o_block_driver);
1187	if (rc) {
1188		osm_err("Could not register Block driver\n");
1189		goto unregister_blkdev;
1190	}
1191
1192	return 0;
1193
1194      unregister_blkdev:
1195	unregister_blkdev(I2O_MAJOR, "i2o_block");
1196
1197      free_mempool:
1198	mempool_destroy(i2o_blk_req_pool.pool);
1199
1200      free_slab:
1201	kmem_cache_destroy(i2o_blk_req_pool.slab);
1202
1203      exit:
1204	return rc;
1205};
1206
1207/**
1208 *	i2o_block_exit - Block OSM exit function
1209 *
1210 *	Unregisters Block OSM from I2O core, unregisters i2o_block block device
1211 *	and frees the mempool and slab.
1212 */
1213static void __exit i2o_block_exit(void)
1214{
1215	/* Unregister I2O Block OSM from I2O core */
1216	i2o_driver_unregister(&i2o_block_driver);
1217
1218	/* Unregister block device */
1219	unregister_blkdev(I2O_MAJOR, "i2o_block");
1220
1221	/* Free request mempool and slab */
1222	mempool_destroy(i2o_blk_req_pool.pool);
1223	kmem_cache_destroy(i2o_blk_req_pool.slab);
1224};
1225
1226MODULE_AUTHOR("Red Hat");
1227MODULE_LICENSE("GPL");
1228MODULE_DESCRIPTION(OSM_DESCRIPTION);
1229MODULE_VERSION(OSM_VERSION);
1230
1231module_init(i2o_block_init);
1232module_exit(i2o_block_exit);
1233