[GitHub/mt8127/android_kernel_alcatel_ttab.git] / block / ioctl.c

#include <linux/capability.h>
#include <linux/blkdev.h>
#include <linux/blkpg.h>
#include <linux/hdreg.h>
#include <linux/backing-dev.h>
#include <linux/buffer_head.h>
#include <linux/smp_lock.h>
#include <linux/blktrace_api.h>
#include <asm/uaccess.h>

static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
{
	struct block_device *bdevp;
	struct gendisk *disk;
	struct hd_struct *part;
	struct blkpg_ioctl_arg a;
	struct blkpg_partition p;
	struct disk_part_iter piter;
	long long start, length;
	int partno;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
		return -EFAULT;
	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
		return -EFAULT;
	disk = bdev->bd_disk;
	if (bdev != bdev->bd_contains)
		return -EINVAL;
	partno = p.pno;
	if (partno <= 0)
		return -EINVAL;
	switch (a.op) {
		case BLKPG_ADD_PARTITION:
			start = p.start >> 9;
			length = p.length >> 9;
			/* check for fit in a hd_struct */ 
			if (sizeof(sector_t) == sizeof(long) && 
			    sizeof(long long) > sizeof(long)) {
				long pstart = start, plength = length;
				if (pstart != start || plength != length
				    || pstart < 0 || plength < 0)
					return -EINVAL;
			}

			mutex_lock(&bdev->bd_mutex);

			/* overlap? */
			disk_part_iter_init(&piter, disk,
					    DISK_PITER_INCL_EMPTY);
			while ((part = disk_part_iter_next(&piter))) {
				if (!(start + length <= part->start_sect ||
				      start >= part->start_sect + part->nr_sects)) {
					disk_part_iter_exit(&piter);
					mutex_unlock(&bdev->bd_mutex);
					return -EBUSY;
				}
			}
			disk_part_iter_exit(&piter);

			/* all seems OK */
			err = add_partition(disk, partno, start, length,
					    ADDPART_FLAG_NONE);
			mutex_unlock(&bdev->bd_mutex);
			return err;
		case BLKPG_DEL_PARTITION:
			part = disk_get_part(disk, partno);
			if (!part)
				return -ENXIO;

			bdevp = bdget(part_devt(part));
			disk_put_part(part);
			if (!bdevp)
				return -ENOMEM;

			mutex_lock(&bdevp->bd_mutex);
			if (bdevp->bd_openers) {
				mutex_unlock(&bdevp->bd_mutex);
				bdput(bdevp);
				return -EBUSY;
			}
			/* all seems OK */
			fsync_bdev(bdevp);
			invalidate_bdev(bdevp);

			mutex_lock_nested(&bdev->bd_mutex, 1);
			delete_partition(disk, partno);
			mutex_unlock(&bdev->bd_mutex);
			mutex_unlock(&bdevp->bd_mutex);
			bdput(bdevp);

			return 0;
		default:
			return -EINVAL;
	}
}

static int blkdev_reread_part(struct block_device *bdev)
{
	struct gendisk *disk = bdev->bd_disk;
	int res;

	if (!disk_partitionable(disk) || bdev != bdev->bd_contains)
		return -EINVAL;
	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if (!mutex_trylock(&bdev->bd_mutex))
		return -EBUSY;
	res = rescan_partitions(disk, bdev);
	mutex_unlock(&bdev->bd_mutex);
	return res;
}

static void blk_ioc_discard_endio(struct bio *bio, int err)
{
	if (err) {
		if (err == -EOPNOTSUPP)
			set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
		clear_bit(BIO_UPTODATE, &bio->bi_flags);
	}
	complete(bio->bi_private);
}

static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
			     uint64_t len)
{
	struct request_queue *q = bdev_get_queue(bdev);
	int ret = 0;

	if (start & 511)
		return -EINVAL;
	if (len & 511)
		return -EINVAL;
	start >>= 9;
	len >>= 9;

	if (start + len > (bdev->bd_inode->i_size >> 9))
		return -EINVAL;

	if (!q->prepare_discard_fn)
		return -EOPNOTSUPP;

	while (len && !ret) {
		DECLARE_COMPLETION_ONSTACK(wait);
		struct bio *bio;

		bio = bio_alloc(GFP_KERNEL, 0);
		if (!bio)
			return -ENOMEM;

		bio->bi_end_io = blk_ioc_discard_endio;
		bio->bi_bdev = bdev;
		bio->bi_private = &wait;
		bio->bi_sector = start;

		if (len > q->max_hw_sectors) {
			bio->bi_size = q->max_hw_sectors << 9;
			len -= q->max_hw_sectors;
			start += q->max_hw_sectors;
		} else {
			bio->bi_size = len << 9;
			len = 0;
		}
		submit_bio(DISCARD_NOBARRIER, bio);

		wait_for_completion(&wait);

		if (bio_flagged(bio, BIO_EOPNOTSUPP))
			ret = -EOPNOTSUPP;
		else if (!bio_flagged(bio, BIO_UPTODATE))
			ret = -EIO;
		bio_put(bio);
	}
	return ret;
}

static int put_ushort(unsigned long arg, unsigned short val)
{
	return put_user(val, (unsigned short __user *)arg);
}

static int put_int(unsigned long arg, int val)
{
	return put_user(val, (int __user *)arg);
}

static int put_long(unsigned long arg, long val)
{
	return put_user(val, (long __user *)arg);
}

static int put_ulong(unsigned long arg, unsigned long val)
{
	return put_user(val, (unsigned long __user *)arg);
}

static int put_u64(unsigned long arg, u64 val)
{
	return put_user(val, (u64 __user *)arg);
}

int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
			unsigned cmd, unsigned long arg)
{
	struct gendisk *disk = bdev->bd_disk;
	int ret;

	if (disk->fops->ioctl)
		return disk->fops->ioctl(bdev, mode, cmd, arg);

	if (disk->fops->locked_ioctl) {
		lock_kernel();
		ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg);
		unlock_kernel();
		return ret;
	}

	return -ENOTTY;
}
/*
 * For the record: _GPL here is only because somebody decided to slap it
 * on the previous export.  Sheer idiocy, since it wasn't copyrightable
 * at all and could be open-coded without any exports by anybody who cares.
 */
EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);

/*
 * always keep this in sync with compat_blkdev_ioctl() and
 * compat_blkdev_locked_ioctl()
 */
int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
			unsigned long arg)
{
	struct gendisk *disk = bdev->bd_disk;
	struct backing_dev_info *bdi;
	loff_t size;
	int ret, n;

	switch(cmd) {
	case BLKFLSBUF:
		if (!capable(CAP_SYS_ADMIN))
			return -EACCES;

		ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
		/* -EINVAL to handle old uncorrected drivers */
		if (ret != -EINVAL && ret != -ENOTTY)
			return ret;

		lock_kernel();
		fsync_bdev(bdev);
		invalidate_bdev(bdev);
		unlock_kernel();
		return 0;

	case BLKROSET:
		ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
		/* -EINVAL to handle old uncorrected drivers */
		if (ret != -EINVAL && ret != -ENOTTY)
			return ret;
		if (!capable(CAP_SYS_ADMIN))
			return -EACCES;
		if (get_user(n, (int __user *)(arg)))
			return -EFAULT;
		lock_kernel();
		set_device_ro(bdev, n);
		unlock_kernel();
		return 0;

	case BLKDISCARD: {
		uint64_t range[2];

		if (!(mode & FMODE_WRITE))
			return -EBADF;

		if (copy_from_user(range, (void __user *)arg, sizeof(range)))
			return -EFAULT;

		return blk_ioctl_discard(bdev, range[0], range[1]);
	}

	case HDIO_GETGEO: {
		struct hd_geometry geo;

		if (!arg)
			return -EINVAL;
		if (!disk->fops->getgeo)
			return -ENOTTY;

		/*
		 * We need to set the startsect first, the driver may
		 * want to override it.
		 */
		geo.start = get_start_sect(bdev);
		ret = disk->fops->getgeo(bdev, &geo);
		if (ret)
			return ret;
		if (copy_to_user((struct hd_geometry __user *)arg, &geo,
					sizeof(geo)))
			return -EFAULT;
		return 0;
	}
	case BLKRAGET:
	case BLKFRAGET:
		if (!arg)
			return -EINVAL;
		bdi = blk_get_backing_dev_info(bdev);
		if (bdi == NULL)
			return -ENOTTY;
		return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
	case BLKROGET:
		return put_int(arg, bdev_read_only(bdev) != 0);
	case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
		return put_int(arg, block_size(bdev));
	case BLKSSZGET: /* get block device hardware sector size */
		return put_int(arg, bdev_hardsect_size(bdev));
	case BLKSECTGET:
		return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
	case BLKRASET:
	case BLKFRASET:
		if(!capable(CAP_SYS_ADMIN))
			return -EACCES;
		bdi = blk_get_backing_dev_info(bdev);
		if (bdi == NULL)
			return -ENOTTY;
		lock_kernel();
		bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
		unlock_kernel();
		return 0;
	case BLKBSZSET:
		/* set the logical block size */
		if (!capable(CAP_SYS_ADMIN))
			return -EACCES;
		if (!arg)
			return -EINVAL;
		if (get_user(n, (int __user *) arg))
			return -EFAULT;
		if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0)
			return -EBUSY;
		ret = set_blocksize(bdev, n);
		if (!(mode & FMODE_EXCL))
			bd_release(bdev);
		return ret;
	case BLKPG:
		lock_kernel();
		ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
		unlock_kernel();
		break;
	case BLKRRPART:
		lock_kernel();
		ret = blkdev_reread_part(bdev);
		unlock_kernel();
		break;
	case BLKGETSIZE:
		size = bdev->bd_inode->i_size;
		if ((size >> 9) > ~0UL)
			return -EFBIG;
		return put_ulong(arg, size >> 9);
	case BLKGETSIZE64:
		return put_u64(arg, bdev->bd_inode->i_size);
	case BLKTRACESTART:
	case BLKTRACESTOP:
	case BLKTRACESETUP:
	case BLKTRACETEARDOWN:
		lock_kernel();
		ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
		unlock_kernel();
		break;
	default:
		ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
	}
	return ret;
}
EXPORT_SYMBOL_GPL(blkdev_ioctl);
Commit	Line	Data
c59ede7b	1	#include <linux/capability.h>
1da177e4 LT	2	#include <linux/blkdev.h>
1da177e4 LT	3	#include <linux/blkpg.h>
a885c8c4	4	#include <linux/hdreg.h>
1da177e4 LT	5	#include <linux/backing-dev.h>
	6	#include <linux/buffer_head.h>
	7	#include <linux/smp_lock.h>
2056a782	8	#include <linux/blktrace_api.h>
1da177e4 LT	9	#include <asm/uaccess.h>
	10
	11	static int blkpg_ioctl(struct block_device bdev, struct blkpg_ioctl_arg __user arg)
	12	{
	13	struct block_device *bdevp;
	14	struct gendisk *disk;
e71bf0d0	15	struct hd_struct *part;
1da177e4 LT	16	struct blkpg_ioctl_arg a;
1da177e4 LT	17	struct blkpg_partition p;
e71bf0d0	18	struct disk_part_iter piter;
1da177e4	19	long long start, length;
cf771cb5	20	int partno;
04ebd4ae	21	int err;
1da177e4 LT	22
	23	if (!capable(CAP_SYS_ADMIN))
	24	return -EACCES;
	25	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
	26	return -EFAULT;
	27	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
	28	return -EFAULT;
	29	disk = bdev->bd_disk;
	30	if (bdev != bdev->bd_contains)
	31	return -EINVAL;
cf771cb5	32	partno = p.pno;
540eed56	33	if (partno <= 0)
1da177e4 LT	34	return -EINVAL;
	35	switch (a.op) {
	36	case BLKPG_ADD_PARTITION:
	37	start = p.start >> 9;
	38	length = p.length >> 9;
	39	/* check for fit in a hd_struct */
	40	if (sizeof(sector_t) == sizeof(long) &&
	41	sizeof(long long) > sizeof(long)) {
	42	long pstart = start, plength = length;
	43	if (pstart != start \|\| plength != length
	44	\|\| pstart < 0 \|\| plength < 0)
	45	return -EINVAL;
	46	}
88e34126	47
c039e313	48	mutex_lock(&bdev->bd_mutex);
88e34126	49
1da177e4	50	/* overlap? */
e71bf0d0 TH	51	disk_part_iter_init(&piter, disk,
	52	DISK_PITER_INCL_EMPTY);
	53	while ((part = disk_part_iter_next(&piter))) {
	54	if (!(start + length <= part->start_sect \|\|
	55	start >= part->start_sect + part->nr_sects)) {
	56	disk_part_iter_exit(&piter);
c039e313	57	mutex_unlock(&bdev->bd_mutex);
1da177e4 LT	58	return -EBUSY;
	59	}
	60	}
e71bf0d0 TH	61	disk_part_iter_exit(&piter);
e71bf0d0 TH	62
1da177e4	63	/* all seems OK */
cf771cb5 TH	64	err = add_partition(disk, partno, start, length,
cf771cb5 TH	65	ADDPART_FLAG_NONE);
c039e313	66	mutex_unlock(&bdev->bd_mutex);
04ebd4ae	67	return err;
1da177e4	68	case BLKPG_DEL_PARTITION:
e71bf0d0 TH	69	part = disk_get_part(disk, partno);
e71bf0d0 TH	70	if (!part)
1da177e4	71	return -ENXIO;
e71bf0d0 TH	72
	73	bdevp = bdget(part_devt(part));
	74	disk_put_part(part);
1da177e4 LT	75	if (!bdevp)
1da177e4 LT	76	return -ENOMEM;
e71bf0d0	77
2e7b651d	78	mutex_lock(&bdevp->bd_mutex);
1da177e4	79	if (bdevp->bd_openers) {
c039e313	80	mutex_unlock(&bdevp->bd_mutex);
1da177e4 LT	81	bdput(bdevp);
	82	return -EBUSY;
	83	}
	84	/* all seems OK */
	85	fsync_bdev(bdevp);
f98393a6	86	invalidate_bdev(bdevp);
1da177e4	87
6d740cd5	88	mutex_lock_nested(&bdev->bd_mutex, 1);
cf771cb5	89	delete_partition(disk, partno);
c039e313 AV	90	mutex_unlock(&bdev->bd_mutex);
c039e313 AV	91	mutex_unlock(&bdevp->bd_mutex);
1da177e4 LT	92	bdput(bdevp);
	93
	94	return 0;
	95	default:
	96	return -EINVAL;
	97	}
	98	}
	99
	100	static int blkdev_reread_part(struct block_device *bdev)
	101	{
	102	struct gendisk *disk = bdev->bd_disk;
	103	int res;
	104
b5d0b9df	105	if (!disk_partitionable(disk) \|\| bdev != bdev->bd_contains)
1da177e4 LT	106	return -EINVAL;
	107	if (!capable(CAP_SYS_ADMIN))
	108	return -EACCES;
c039e313	109	if (!mutex_trylock(&bdev->bd_mutex))
1da177e4 LT	110	return -EBUSY;
1da177e4 LT	111	res = rescan_partitions(disk, bdev);
c039e313	112	mutex_unlock(&bdev->bd_mutex);
1da177e4 LT	113	return res;
	114	}
	115
d30a2605 DW	116	static void blk_ioc_discard_endio(struct bio *bio, int err)
	117	{
	118	if (err) {
	119	if (err == -EOPNOTSUPP)
	120	set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
	121	clear_bit(BIO_UPTODATE, &bio->bi_flags);
	122	}
	123	complete(bio->bi_private);
	124	}
	125
	126	static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
	127	uint64_t len)
	128	{
	129	struct request_queue *q = bdev_get_queue(bdev);
	130	int ret = 0;
	131
	132	if (start & 511)
	133	return -EINVAL;
	134	if (len & 511)
	135	return -EINVAL;
	136	start >>= 9;
	137	len >>= 9;
	138
	139	if (start + len > (bdev->bd_inode->i_size >> 9))
	140	return -EINVAL;
	141
	142	if (!q->prepare_discard_fn)
	143	return -EOPNOTSUPP;
	144
	145	while (len && !ret) {
	146	DECLARE_COMPLETION_ONSTACK(wait);
	147	struct bio *bio;
	148
	149	bio = bio_alloc(GFP_KERNEL, 0);
	150	if (!bio)
	151	return -ENOMEM;
	152
	153	bio->bi_end_io = blk_ioc_discard_endio;
	154	bio->bi_bdev = bdev;
	155	bio->bi_private = &wait;
	156	bio->bi_sector = start;
	157
	158	if (len > q->max_hw_sectors) {
	159	bio->bi_size = q->max_hw_sectors << 9;
	160	len -= q->max_hw_sectors;
	161	start += q->max_hw_sectors;
	162	} else {
	163	bio->bi_size = len << 9;
	164	len = 0;
	165	}
e17fc0a1	166	submit_bio(DISCARD_NOBARRIER, bio);
d30a2605 DW	167
	168	wait_for_completion(&wait);
	169
	170	if (bio_flagged(bio, BIO_EOPNOTSUPP))
	171	ret = -EOPNOTSUPP;
	172	else if (!bio_flagged(bio, BIO_UPTODATE))
	173	ret = -EIO;
	174	bio_put(bio);
	175	}
	176	return ret;
	177	}
	178
1da177e4 LT	179	static int put_ushort(unsigned long arg, unsigned short val)
	180	{
	181	return put_user(val, (unsigned short __user *)arg);
	182	}
	183
	184	static int put_int(unsigned long arg, int val)
	185	{
	186	return put_user(val, (int __user *)arg);
	187	}
	188
	189	static int put_long(unsigned long arg, long val)
	190	{
	191	return put_user(val, (long __user *)arg);
	192	}
	193
	194	static int put_ulong(unsigned long arg, unsigned long val)
	195	{
	196	return put_user(val, (unsigned long __user *)arg);
	197	}
	198
	199	static int put_u64(unsigned long arg, u64 val)
	200	{
	201	return put_user(val, (u64 __user *)arg);
	202	}
	203
633a08b8 AV	204	int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
	205	unsigned cmd, unsigned long arg)
	206	{
	207	struct gendisk *disk = bdev->bd_disk;
	208	int ret;
d4430d62 AV	209
	210	if (disk->fops->ioctl)
	211	return disk->fops->ioctl(bdev, mode, cmd, arg);
633a08b8	212
d4430d62	213	if (disk->fops->locked_ioctl) {
633a08b8	214	lock_kernel();
d4430d62	215	ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg);
633a08b8 AV	216	unlock_kernel();
	217	return ret;
	218	}
	219
	220	return -ENOTTY;
	221	}
	222	/*
	223	* For the record: _GPL here is only because somebody decided to slap it
	224	* on the previous export. Sheer idiocy, since it wasn't copyrightable
	225	* at all and could be open-coded without any exports by anybody who cares.
	226	*/
	227	EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
	228
f58c4c0a AB	229	/*
	230	* always keep this in sync with compat_blkdev_ioctl() and
	231	* compat_blkdev_locked_ioctl()
	232	*/
56b26add	233	int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
bb93e3a5 AB	234	unsigned long arg)
bb93e3a5 AB	235	{
bb93e3a5	236	struct gendisk *disk = bdev->bd_disk;
45048d09 AV	237	struct backing_dev_info *bdi;
45048d09 AV	238	loff_t size;
bb93e3a5 AB	239	int ret, n;
	240
	241	switch(cmd) {
1da177e4 LT	242	case BLKFLSBUF:
	243	if (!capable(CAP_SYS_ADMIN))
	244	return -EACCES;
bb93e3a5	245
e436fdae	246	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
bb93e3a5 AB	247	/* -EINVAL to handle old uncorrected drivers */
	248	if (ret != -EINVAL && ret != -ENOTTY)
	249	return ret;
	250
	251	lock_kernel();
1da177e4	252	fsync_bdev(bdev);
f98393a6	253	invalidate_bdev(bdev);
bb93e3a5	254	unlock_kernel();
1da177e4	255	return 0;
bb93e3a5	256
1da177e4	257	case BLKROSET:
e436fdae	258	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
bb93e3a5 AB	259	/* -EINVAL to handle old uncorrected drivers */
	260	if (ret != -EINVAL && ret != -ENOTTY)
	261	return ret;
1da177e4 LT	262	if (!capable(CAP_SYS_ADMIN))
	263	return -EACCES;
	264	if (get_user(n, (int __user *)(arg)))
	265	return -EFAULT;
bb93e3a5	266	lock_kernel();
1da177e4	267	set_device_ro(bdev, n);
bb93e3a5	268	unlock_kernel();
1da177e4	269	return 0;
d30a2605 DW	270
	271	case BLKDISCARD: {
	272	uint64_t range[2];
	273
e436fdae	274	if (!(mode & FMODE_WRITE))
d30a2605 DW	275	return -EBADF;
	276
	277	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
	278	return -EFAULT;
	279
	280	return blk_ioctl_discard(bdev, range[0], range[1]);
	281	}
	282
a885c8c4 CH	283	case HDIO_GETGEO: {
	284	struct hd_geometry geo;
	285
	286	if (!arg)
	287	return -EINVAL;
	288	if (!disk->fops->getgeo)
	289	return -ENOTTY;
	290
	291	/*
	292	* We need to set the startsect first, the driver may
	293	* want to override it.
	294	*/
	295	geo.start = get_start_sect(bdev);
	296	ret = disk->fops->getgeo(bdev, &geo);
	297	if (ret)
	298	return ret;
	299	if (copy_to_user((struct hd_geometry __user *)arg, &geo,
	300	sizeof(geo)))
	301	return -EFAULT;
	302	return 0;
	303	}
45048d09 AV	304	case BLKRAGET:
	305	case BLKFRAGET:
	306	if (!arg)
	307	return -EINVAL;
	308	bdi = blk_get_backing_dev_info(bdev);
	309	if (bdi == NULL)
	310	return -ENOTTY;
	311	return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
	312	case BLKROGET:
	313	return put_int(arg, bdev_read_only(bdev) != 0);
	314	case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
	315	return put_int(arg, block_size(bdev));
	316	case BLKSSZGET: /* get block device hardware sector size */
	317	return put_int(arg, bdev_hardsect_size(bdev));
	318	case BLKSECTGET:
	319	return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
	320	case BLKRASET:
	321	case BLKFRASET:
	322	if(!capable(CAP_SYS_ADMIN))
	323	return -EACCES;
	324	bdi = blk_get_backing_dev_info(bdev);
	325	if (bdi == NULL)
	326	return -ENOTTY;
	327	lock_kernel();
	328	bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
	329	unlock_kernel();
	330	return 0;
	331	case BLKBSZSET:
	332	/* set the logical block size */
	333	if (!capable(CAP_SYS_ADMIN))
	334	return -EACCES;
	335	if (!arg)
	336	return -EINVAL;
	337	if (get_user(n, (int __user *) arg))
	338	return -EFAULT;
6af3a56e	339	if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0)
45048d09 AV	340	return -EBUSY;
45048d09 AV	341	ret = set_blocksize(bdev, n);
6af3a56e AV	342	if (!(mode & FMODE_EXCL))
6af3a56e AV	343	bd_release(bdev);
bb93e3a5	344	return ret;
45048d09 AV	345	case BLKPG:
	346	lock_kernel();
	347	ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
	348	unlock_kernel();
	349	break;
	350	case BLKRRPART:
	351	lock_kernel();
	352	ret = blkdev_reread_part(bdev);
	353	unlock_kernel();
	354	break;
	355	case BLKGETSIZE:
	356	size = bdev->bd_inode->i_size;
	357	if ((size >> 9) > ~0UL)
	358	return -EFBIG;
	359	return put_ulong(arg, size >> 9);
	360	case BLKGETSIZE64:
	361	return put_u64(arg, bdev->bd_inode->i_size);
	362	case BLKTRACESTART:
	363	case BLKTRACESTOP:
	364	case BLKTRACESETUP:
	365	case BLKTRACETEARDOWN:
	366	lock_kernel();
	367	ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
	368	unlock_kernel();
	369	break;
	370	default:
	371	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
	372	}
	373	return ret;
1da177e4	374	}
68f66feb	375	EXPORT_SYMBOL_GPL(blkdev_ioctl);