From 66ba32dc167202c3cf8c86806581a9393ec7f488 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Tue, 18 Sep 2012 12:19:29 -0400 Subject: block: ioctl to zero block ranges Introduce a BLKZEROOUT ioctl which can be used to clear block ranges by way of blkdev_issue_zeroout(). Signed-off-by: Martin K. Petersen Acked-by: Mike Snitzer Signed-off-by: Jens Axboe --- block/ioctl.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'block/ioctl.c') diff --git a/block/ioctl.c b/block/ioctl.c index 4476e0e85d16..769d2960c0a6 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -185,6 +185,22 @@ static int blk_ioctl_discard(struct block_device *bdev, uint64_t start, return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags); } +static int blk_ioctl_zeroout(struct block_device *bdev, uint64_t start, + uint64_t len) +{ + if (start & 511) + return -EINVAL; + if (len & 511) + return -EINVAL; + start >>= 9; + len >>= 9; + + if (start + len > (i_size_read(bdev->bd_inode) >> 9)) + return -EINVAL; + + return blkdev_issue_zeroout(bdev, start, len, GFP_KERNEL); +} + static int put_ushort(unsigned long arg, unsigned short val) { return put_user(val, (unsigned short __user *)arg); @@ -300,6 +316,17 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, return blk_ioctl_discard(bdev, range[0], range[1], cmd == BLKSECDISCARD); } + case BLKZEROOUT: { + 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_zeroout(bdev, range[0], range[1]); + } case HDIO_GETGEO: { struct hd_geometry geo; -- cgit v1.2.2