diff options
| author | Davidlohr Bueso | 2011-04-09 02:20:49 +0200 |
|---|---|---|
| committer | Karel Zak | 2011-04-12 13:08:52 +0200 |
| commit | ba326929706ec4dc8ab8bc0a09868bcd6fd6d75f (patch) | |
| tree | 645e388dc4cfa9867db938b5fdf038718964ea70 | |
| parent | hexdump: don't include err.h directly (diff) | |
| download | kernel-qcow2-util-linux-ba326929706ec4dc8ab8bc0a09868bcd6fd6d75f.tar.gz kernel-qcow2-util-linux-ba326929706ec4dc8ab8bc0a09868bcd6fd6d75f.tar.xz kernel-qcow2-util-linux-ba326929706ec4dc8ab8bc0a09868bcd6fd6d75f.zip | |
blkdev: add blkdev_is_misaligned()
This functions returns the status of the device's alignment. It will
be 0 when aligned, otherwise return the offset.
[kzak@redhat.com: - returns 0 if the ioctl failed]
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
| -rw-r--r-- | include/blkdev.h | 3 | ||||
| -rw-r--r-- | lib/blkdev.c | 12 |
2 files changed, 15 insertions, 0 deletions
diff --git a/include/blkdev.h b/include/blkdev.h index b6c46edde..6a641723f 100644 --- a/include/blkdev.h +++ b/include/blkdev.h @@ -92,4 +92,7 @@ int blkdev_get_sectors(int fd, unsigned long long *sectors); /* get hardware sector size */ int blkdev_get_sector_size(int fd, int *sector_size); +/* specifies whether or not the device is misaligned */ +int blkdev_is_misaligned(int fd); + #endif /* BLKDEV_H */ diff --git a/lib/blkdev.c b/lib/blkdev.c index 0c27a6df9..fb69e88b5 100644 --- a/lib/blkdev.c +++ b/lib/blkdev.c @@ -205,6 +205,18 @@ blkdev_get_sector_size(int fd, int *sector_size) } +/* + * Return the alignment status of a device + */ +int blkdev_is_misaligned(int fd) +{ + int aligned; + + if (ioctl(fd, BLKALIGNOFF, &aligned) < 0) + return 0; /* probably kernel < 2.6.32 */ + return aligned; +} + #ifdef TEST_PROGRAM #include <stdio.h> #include <stdlib.h> |