block: Topology ioctls

Not all users of the topology information want to use libblkid.  Provide
the topology information through bdev ioctls.

Also clarify sector size comments for existing BLK ioctls.

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

1 files changed, 13 insertions, 0 deletions

diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 7865a34e0faa..9bd086c1a4d5 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -21,6 +21,11 @@ static int compat_put_int(unsigned long arg, int val)
         return put_user(val, (compat_int_t __user *)compat_ptr(arg));
 }
 
+static int compat_put_uint(unsigned long arg, unsigned int val)
+{
+        return put_user(val, (compat_uint_t __user *)compat_ptr(arg));
+}
+
 static int compat_put_long(unsigned long arg, long val)
 {
         return put_user(val, (compat_long_t __user *)compat_ptr(arg));
@@ -734,6 +739,14 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
         switch (cmd) {
         case HDIO_GETGEO:
                 return compat_hdio_getgeo(disk, bdev, compat_ptr(arg));
+        case BLKPBSZGET:
+                return compat_put_uint(arg, bdev_physical_block_size(bdev));
+        case BLKIOMIN:
+                return compat_put_uint(arg, bdev_io_min(bdev));
+        case BLKIOOPT:
+                return compat_put_uint(arg, bdev_io_opt(bdev));
+        case BLKALIGNOFF:
+                return compat_put_int(arg, bdev_alignment_offset(bdev));
         case BLKFLSBUF:
         case BLKROSET:
         case BLKDISCARD: