forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

dm ioctl: allow message to return data

Browse source 
This patch introduces enhanced message support that allows the
device-mapper core to recognise messages that are common to all devices,
and for messages to return data to userspace.

Core messages are processed by the function "message_for_md".  If the
device mapper doesn't support the message, it is passed to the target
driver.

If the message returns data, the kernel sets the flag
DM_MESSAGE_OUT_FLAG.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mikulas Patocka 2013-03-01 22:45:49 +00:00 • committed by Alasdair G Kergon
parent 02cde50b7e
commit a26062416e
2 changed files with 40 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

5
include/uapi/linux/dm-ioctl.h
View file

@ -336,4 +336,9 @@ enum {
*/
#define DM_SECURE_DATA_FLAG (1 << 15) /* In */
/*
* If set, a message generated output data.
*/
#define DM_DATA_OUT_FLAG (1 << 16) /* Out */
#endif /* _LINUX_DM_IOCTL_H */