From: Martin K. Petersen <martin.petersen@oracle.com>
Date: Wed, 11 Jan 2012 15:29:31 +0000 (+0100)
Subject: block: Add BLKROTATIONAL ioctl
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ef00f59c95fe6e002e7c6e3663cdea65e253f4cc;p=openwrt%2Fstaging%2Fblogic.git

block: Add BLKROTATIONAL ioctl

Introduce an ioctl which permits applications to query whether a block
device is rotational.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 7b725020823c..7c668c8a6f95 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -719,6 +719,9 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	case BLKSECTGET:
 		return compat_put_ushort(arg,
 					 queue_max_sectors(bdev_get_queue(bdev)));
+	case BLKROTATIONAL:
+		return compat_put_ushort(arg,
+					 !blk_queue_nonrot(bdev_get_queue(bdev)));
 	case BLKRASET: /* compatible, but no compat_ptr (!) */
 	case BLKFRASET:
 		if (!capable(CAP_SYS_ADMIN))
diff --git a/block/ioctl.c b/block/ioctl.c
index ca939fc1030f..337d207ab14d 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -278,6 +278,8 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 		return put_uint(arg, bdev_discard_zeroes_data(bdev));
 	case BLKSECTGET:
 		return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev)));
+	case BLKROTATIONAL:
+		return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev)));
 	case BLKRASET:
 	case BLKFRASET:
 		if(!capable(CAP_SYS_ADMIN))
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e0bc4ffb8e7f..95dd911506f1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -319,6 +319,7 @@ struct inodes_stat_t {
 #define BLKPBSZGET _IO(0x12,123)
 #define BLKDISCARDZEROES _IO(0x12,124)
 #define BLKSECDISCARD _IO(0x12,125)
+#define BLKROTATIONAL _IO(0x12,126)
 
 #define BMAP_IOCTL 1		/* obsolete - kept for compatibility */
 #define FIBMAP	   _IO(0x00,1)	/* bmap access */