[linux-2.6-block.git] / drivers / block / rsxx / dev.c

/*
* Filename: dev.c
*
*
* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
*
* (C) Copyright 2013 IBM Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/blkdev.h>
#include <linux/bio.h>

#include <linux/fs.h>

#include "rsxx_priv.h"

static unsigned int blkdev_minors = 64;
module_param(blkdev_minors, uint, 0444);
MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)");

/*
 * For now I'm making this tweakable in case any applications hit this limit.
 * If you see a "bio too big" error in the log you will need to raise this
 * value.
 */
static unsigned int blkdev_max_hw_sectors = 1024;
module_param(blkdev_max_hw_sectors, uint, 0444);
MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO");

static unsigned int enable_blkdev = 1;
module_param(enable_blkdev , uint, 0444);
MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");


struct rsxx_bio_meta {
	struct bio	*bio;
	atomic_t	pending_dmas;
	atomic_t	error;
	unsigned long	start_time;
};

static struct kmem_cache *bio_meta_pool;

/*----------------- Block Device Operations -----------------*/
static int rsxx_blkdev_ioctl(struct block_device *bdev,
				 fmode_t mode,
				 unsigned int cmd,
				 unsigned long arg)
{
	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;

	switch (cmd) {
	case RSXX_GETREG:
		return rsxx_reg_access(card, (void __user *)arg, 1);
	case RSXX_SETREG:
		return rsxx_reg_access(card, (void __user *)arg, 0);
	}

	return -ENOTTY;
}

static int rsxx_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
	u64 blocks = card->size8 >> 9;

	/*
	 * get geometry: Fake it. I haven't found any drivers that set
	 * geo->start, so we won't either.
	 */
	if (card->size8) {
		geo->heads = 64;
		geo->sectors = 16;
		do_div(blocks, (geo->heads * geo->sectors));
		geo->cylinders = blocks;
	} else {
		geo->heads = 0;
		geo->sectors = 0;
		geo->cylinders = 0;
	}
	return 0;
}

static const struct block_device_operations rsxx_fops = {
	.owner		= THIS_MODULE,
	.getgeo		= rsxx_getgeo,
	.ioctl		= rsxx_blkdev_ioctl,
};

static void disk_stats_start(struct rsxx_cardinfo *card, struct bio *bio)
{
	struct hd_struct *part0 = &card->gendisk->part0;
	int rw = bio_data_dir(bio);
	int cpu;

	cpu = part_stat_lock();

	part_round_stats(cpu, part0);
	part_inc_in_flight(part0, rw);

	part_stat_unlock();
}

static void disk_stats_complete(struct rsxx_cardinfo *card,
				struct bio *bio,
				unsigned long start_time)
{
	struct hd_struct *part0 = &card->gendisk->part0;
	unsigned long duration = jiffies - start_time;
	int rw = bio_data_dir(bio);
	int cpu;

	cpu = part_stat_lock();

	part_stat_add(cpu, part0, sectors[rw], bio_sectors(bio));
	part_stat_inc(cpu, part0, ios[rw]);
	part_stat_add(cpu, part0, ticks[rw], duration);

	part_round_stats(cpu, part0);
	part_dec_in_flight(part0, rw);

	part_stat_unlock();
}

static void bio_dma_done_cb(struct rsxx_cardinfo *card,
			    void *cb_data,
			    unsigned int error)
{
	struct rsxx_bio_meta *meta = cb_data;

	if (error)
		atomic_set(&meta->error, 1);

	if (atomic_dec_and_test(&meta->pending_dmas)) {
		if (!card->eeh_state && card->gendisk)
			disk_stats_complete(card, meta->bio, meta->start_time);

		bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
		kmem_cache_free(bio_meta_pool, meta);
	}
}

static void rsxx_make_request(struct request_queue *q, struct bio *bio)
{
	struct rsxx_cardinfo *card = q->queuedata;
	struct rsxx_bio_meta *bio_meta;
	int st = -EINVAL;

	might_sleep();

	if (!card)
		goto req_err;

	if (bio_end_sector(bio) > get_capacity(card->gendisk))
		goto req_err;

	if (unlikely(card->halt)) {
		st = -EFAULT;
		goto req_err;
	}

	if (unlikely(card->dma_fault)) {
		st = (-EFAULT);
		goto req_err;
	}

	if (bio->bi_iter.bi_size == 0) {
		dev_err(CARD_TO_DEV(card), "size zero BIO!\n");
		goto req_err;
	}

	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);
	if (!bio_meta) {
		st = -ENOMEM;
		goto req_err;
	}

	bio_meta->bio = bio;
	atomic_set(&bio_meta->error, 0);
	atomic_set(&bio_meta->pending_dmas, 0);
	bio_meta->start_time = jiffies;

	if (!unlikely(card->halt))
		disk_stats_start(card, bio);

	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",
		 bio_data_dir(bio) ? 'W' : 'R', bio_meta,
		 (u64)bio->bi_iter.bi_sector << 9, bio->bi_iter.bi_size);

	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,
				    bio_dma_done_cb, bio_meta);
	if (st)
		goto queue_err;

	return;

queue_err:
	kmem_cache_free(bio_meta_pool, bio_meta);
req_err:
	bio_endio(bio, st);
}

/*----------------- Device Setup -------------------*/
static bool rsxx_discard_supported(struct rsxx_cardinfo *card)
{
	unsigned char pci_rev;

	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev);

	return (pci_rev >= RSXX_DISCARD_SUPPORT);
}

int rsxx_attach_dev(struct rsxx_cardinfo *card)
{
	mutex_lock(&card->dev_lock);

	/* The block device requires the stripe size from the config. */
	if (enable_blkdev) {
		if (card->config_valid)
			set_capacity(card->gendisk, card->size8 >> 9);
		else
			set_capacity(card->gendisk, 0);
		add_disk(card->gendisk);

		card->bdev_attached = 1;
	}

	mutex_unlock(&card->dev_lock);

	return 0;
}

void rsxx_detach_dev(struct rsxx_cardinfo *card)
{
	mutex_lock(&card->dev_lock);

	if (card->bdev_attached) {
		del_gendisk(card->gendisk);
		card->bdev_attached = 0;
	}

	mutex_unlock(&card->dev_lock);
}

int rsxx_setup_dev(struct rsxx_cardinfo *card)
{
	unsigned short blk_size;

	mutex_init(&card->dev_lock);

	if (!enable_blkdev)
		return 0;

	card->major = register_blkdev(0, DRIVER_NAME);
	if (card->major < 0) {
		dev_err(CARD_TO_DEV(card), "Failed to get major number\n");
		return -ENOMEM;
	}

	card->queue = blk_alloc_queue(GFP_KERNEL);
	if (!card->queue) {
		dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");
		unregister_blkdev(card->major, DRIVER_NAME);
		return -ENOMEM;
	}

	card->gendisk = alloc_disk(blkdev_minors);
	if (!card->gendisk) {
		dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");
		blk_cleanup_queue(card->queue);
		unregister_blkdev(card->major, DRIVER_NAME);
		return -ENOMEM;
	}

	if (card->config_valid) {
		blk_size = card->config.data.block_size;
		blk_queue_dma_alignment(card->queue, blk_size - 1);
		blk_queue_logical_block_size(card->queue, blk_size);
	}

	blk_queue_make_request(card->queue, rsxx_make_request);
	blk_queue_bounce_limit(card->queue, BLK_BOUNCE_ANY);
	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);
	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE);

	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);
	if (rsxx_discard_supported(card)) {
		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);
		blk_queue_max_discard_sectors(card->queue,
						RSXX_HW_BLK_SIZE >> 9);
		card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;
		card->queue->limits.discard_alignment   = RSXX_HW_BLK_SIZE;
		card->queue->limits.discard_zeroes_data = 1;
	}

	card->queue->queuedata = card;

	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
		 "rsxx%d", card->disk_id);
	card->gendisk->driverfs_dev = &card->dev->dev;
	card->gendisk->major = card->major;
	card->gendisk->first_minor = 0;
	card->gendisk->fops = &rsxx_fops;
	card->gendisk->private_data = card;
	card->gendisk->queue = card->queue;

	return 0;
}

void rsxx_destroy_dev(struct rsxx_cardinfo *card)
{
	if (!enable_blkdev)
		return;

	put_disk(card->gendisk);
	card->gendisk = NULL;

	blk_cleanup_queue(card->queue);
	card->queue->queuedata = NULL;
	unregister_blkdev(card->major, DRIVER_NAME);
}

int rsxx_dev_init(void)
{
	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);
	if (!bio_meta_pool)
		return -ENOMEM;

	return 0;
}

void rsxx_dev_cleanup(void)
{
	kmem_cache_destroy(bio_meta_pool);
}
Commit	Line	Data
8722ff8c	1	/*
	2	* Filename: dev.c
	3	*
	4	*
	5	* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
	6	* Philip Kelleher <pjk1939@linux.vnet.ibm.com>
	7	*
	8	* (C) Copyright 2013 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, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* 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 Foundation,
	22	* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*/
	24
	25	#include <linux/kernel.h>
	26	#include <linux/interrupt.h>
	27	#include <linux/module.h>
	28	#include <linux/pci.h>
	29	#include <linux/slab.h>
	30
	31	#include <linux/hdreg.h>
	32	#include <linux/genhd.h>
	33	#include <linux/blkdev.h>
	34	#include <linux/bio.h>
	35
	36	#include <linux/fs.h>
	37
	38	#include "rsxx_priv.h"
	39
	40	static unsigned int blkdev_minors = 64;
	41	module_param(blkdev_minors, uint, 0444);
	42	MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)");
	43
	44	/*
	45	* For now I'm making this tweakable in case any applications hit this limit.
	46	* If you see a "bio too big" error in the log you will need to raise this
	47	* value.
	48	*/
	49	static unsigned int blkdev_max_hw_sectors = 1024;
	50	module_param(blkdev_max_hw_sectors, uint, 0444);
	51	MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO");
	52
	53	static unsigned int enable_blkdev = 1;
	54	module_param(enable_blkdev , uint, 0444);
	55	MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");
	56
	57
	58	struct rsxx_bio_meta {
	59	struct bio *bio;
	60	atomic_t pending_dmas;
	61	atomic_t error;
	62	unsigned long start_time;
	63	};
	64
65	static struct kmem_cache *bio_meta_pool;
66
67	/----------------- Block Device Operations -----------------/
68	static int rsxx_blkdev_ioctl(struct block_device *bdev,
69	fmode_t mode,
70	unsigned int cmd,
71	unsigned long arg)
72	{
73	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
74
75	switch (cmd) {
76	case RSXX_GETREG:
77	return rsxx_reg_access(card, (void __user *)arg, 1);
78	case RSXX_SETREG:
79	return rsxx_reg_access(card, (void __user *)arg, 0);
80	}
81
82	return -ENOTTY;
83	}
84
85	static int rsxx_getgeo(struct block_device bdev, struct hd_geometry geo)
86	{
87	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
88	u64 blocks = card->size8 >> 9;
89
90	/*
91	* get geometry: Fake it. I haven't found any drivers that set
92	* geo->start, so we won't either.
93	*/
94	if (card->size8) {
95	geo->heads = 64;
96	geo->sectors = 16;
97	do_div(blocks, (geo->heads * geo->sectors));
98	geo->cylinders = blocks;
99	} else {
100	geo->heads = 0;
101	geo->sectors = 0;
102	geo->cylinders = 0;
103	}
104	return 0;
105	}
106
107	static const struct block_device_operations rsxx_fops = {
108	.owner = THIS_MODULE,
109	.getgeo = rsxx_getgeo,
110	.ioctl = rsxx_blkdev_ioctl,
111	};
112
113	static void disk_stats_start(struct rsxx_cardinfo card, struct bio bio)
114	{
115	struct hd_struct *part0 = &card->gendisk->part0;
116	int rw = bio_data_dir(bio);
117	int cpu;
118
119	cpu = part_stat_lock();
120
121	part_round_stats(cpu, part0);
122	part_inc_in_flight(part0, rw);
123
124	part_stat_unlock();
125	}
126
127	static void disk_stats_complete(struct rsxx_cardinfo *card,
128	struct bio *bio,
129	unsigned long start_time)
130	{
131	struct hd_struct *part0 = &card->gendisk->part0;
132	unsigned long duration = jiffies - start_time;
133	int rw = bio_data_dir(bio);
134	int cpu;
135
136	cpu = part_stat_lock();
137
138	part_stat_add(cpu, part0, sectors[rw], bio_sectors(bio));
139	part_stat_inc(cpu, part0, ios[rw]);
140	part_stat_add(cpu, part0, ticks[rw], duration);
141
142	part_round_stats(cpu, part0);
143	part_dec_in_flight(part0, rw);
144
145	part_stat_unlock();
146	}
147
148	static void bio_dma_done_cb(struct rsxx_cardinfo *card,
149	void *cb_data,
150	unsigned int error)
151	{
c206c709	152	struct rsxx_bio_meta *meta = cb_data;
8722ff8c	153
	154	if (error)
	155	atomic_set(&meta->error, 1);
	156
	157	if (atomic_dec_and_test(&meta->pending_dmas)) {
0ab4743e PK	158	if (!card->eeh_state && card->gendisk)
0ab4743e PK	159	disk_stats_complete(card, meta->bio, meta->start_time);
8722ff8c	160
	161	bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
	162	kmem_cache_free(bio_meta_pool, meta);
	163	}
	164	}
	165
	166	static void rsxx_make_request(struct request_queue q, struct bio bio)
	167	{
	168	struct rsxx_cardinfo *card = q->queuedata;
	169	struct rsxx_bio_meta *bio_meta;
	170	int st = -EINVAL;
	171
	172	might_sleep();
	173
66bc6003 PK	174	if (!card)
	175	goto req_err;
	176
4f024f37	177	if (bio_end_sector(bio) > get_capacity(card->gendisk))
3eb8dcaf PK	178	goto req_err;
3eb8dcaf PK	179
8722ff8c	180	if (unlikely(card->halt)) {
	181	st = -EFAULT;
	182	goto req_err;
	183	}
	184
	185	if (unlikely(card->dma_fault)) {
	186	st = (-EFAULT);
	187	goto req_err;
	188	}
	189
4f024f37	190	if (bio->bi_iter.bi_size == 0) {
8722ff8c	191	dev_err(CARD_TO_DEV(card), "size zero BIO!\n");
	192	goto req_err;
	193	}
	194
	195	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);
	196	if (!bio_meta) {
	197	st = -ENOMEM;
	198	goto req_err;
	199	}
	200
	201	bio_meta->bio = bio;
	202	atomic_set(&bio_meta->error, 0);
	203	atomic_set(&bio_meta->pending_dmas, 0);
	204	bio_meta->start_time = jiffies;
	205
0ab4743e PK	206	if (!unlikely(card->halt))
0ab4743e PK	207	disk_stats_start(card, bio);
8722ff8c	208
	209	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",
	210	bio_data_dir(bio) ? 'W' : 'R', bio_meta,
4f024f37	211	(u64)bio->bi_iter.bi_sector << 9, bio->bi_iter.bi_size);
8722ff8c	212
	213	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,
	214	bio_dma_done_cb, bio_meta);
	215	if (st)
	216	goto queue_err;
	217
	218	return;
	219
	220	queue_err:
	221	kmem_cache_free(bio_meta_pool, bio_meta);
	222	req_err:
	223	bio_endio(bio, st);
	224	}
	225
	226	/----------------- Device Setup -------------------/
	227	static bool rsxx_discard_supported(struct rsxx_cardinfo *card)
	228	{
	229	unsigned char pci_rev;
	230
	231	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev);
	232
	233	return (pci_rev >= RSXX_DISCARD_SUPPORT);
	234	}
	235
8722ff8c	236	int rsxx_attach_dev(struct rsxx_cardinfo *card)
	237	{
	238	mutex_lock(&card->dev_lock);
	239
	240	/* The block device requires the stripe size from the config. */
	241	if (enable_blkdev) {
	242	if (card->config_valid)
	243	set_capacity(card->gendisk, card->size8 >> 9);
	244	else
	245	set_capacity(card->gendisk, 0);
	246	add_disk(card->gendisk);
	247
	248	card->bdev_attached = 1;
	249	}
	250
	251	mutex_unlock(&card->dev_lock);
	252
	253	return 0;
	254	}
	255
	256	void rsxx_detach_dev(struct rsxx_cardinfo *card)
	257	{
	258	mutex_lock(&card->dev_lock);
	259
	260	if (card->bdev_attached) {
	261	del_gendisk(card->gendisk);
	262	card->bdev_attached = 0;
	263	}
	264
	265	mutex_unlock(&card->dev_lock);
	266	}
	267
	268	int rsxx_setup_dev(struct rsxx_cardinfo *card)
	269	{
	270	unsigned short blk_size;
	271
	272	mutex_init(&card->dev_lock);
	273
	274	if (!enable_blkdev)
	275	return 0;
	276
	277	card->major = register_blkdev(0, DRIVER_NAME);
	278	if (card->major < 0) {
	279	dev_err(CARD_TO_DEV(card), "Failed to get major number\n");
	280	return -ENOMEM;
	281	}
	282
	283	card->queue = blk_alloc_queue(GFP_KERNEL);
	284	if (!card->queue) {
	285	dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");
	286	unregister_blkdev(card->major, DRIVER_NAME);
	287	return -ENOMEM;
	288	}
	289
	290	card->gendisk = alloc_disk(blkdev_minors);
	291	if (!card->gendisk) {
	292	dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");
	293	blk_cleanup_queue(card->queue);
	294	unregister_blkdev(card->major, DRIVER_NAME);
	295	return -ENOMEM;
	296	}
	297
8c49a77c PK	298	if (card->config_valid) {
	299	blk_size = card->config.data.block_size;
	300	blk_queue_dma_alignment(card->queue, blk_size - 1);
	301	blk_queue_logical_block_size(card->queue, blk_size);
	302	}
8722ff8c	303
	304	blk_queue_make_request(card->queue, rsxx_make_request);
	305	blk_queue_bounce_limit(card->queue, BLK_BOUNCE_ANY);
8722ff8c	306	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);
8722ff8c	307	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE);
	308
	309	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);
	310	if (rsxx_discard_supported(card)) {
	311	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);
	312	blk_queue_max_discard_sectors(card->queue,
	313	RSXX_HW_BLK_SIZE >> 9);
	314	card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;
	315	card->queue->limits.discard_alignment = RSXX_HW_BLK_SIZE;
	316	card->queue->limits.discard_zeroes_data = 1;
	317	}
	318
	319	card->queue->queuedata = card;
	320
	321	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
	322	"rsxx%d", card->disk_id);
	323	card->gendisk->driverfs_dev = &card->dev->dev;
	324	card->gendisk->major = card->major;
	325	card->gendisk->first_minor = 0;
	326	card->gendisk->fops = &rsxx_fops;
	327	card->gendisk->private_data = card;
	328	card->gendisk->queue = card->queue;
	329
	330	return 0;
	331	}
	332
	333	void rsxx_destroy_dev(struct rsxx_cardinfo *card)
	334	{
	335	if (!enable_blkdev)
	336	return;
	337
	338	put_disk(card->gendisk);
	339	card->gendisk = NULL;
	340
	341	blk_cleanup_queue(card->queue);
66bc6003	342	card->queue->queuedata = NULL;
8722ff8c	343	unregister_blkdev(card->major, DRIVER_NAME);
	344	}
	345
	346	int rsxx_dev_init(void)
	347	{
	348	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);
	349	if (!bio_meta_pool)
	350	return -ENOMEM;
	351
	352	return 0;
	353	}
	354
	355	void rsxx_dev_cleanup(void)
	356	{
	357	kmem_cache_destroy(bio_meta_pool);
	358	}
	359
	360