[PATCH] device-mapper ioctl: add skip lock_fs flag

Add ioctl DM_SKIP_LOCKFS_FLAG for userspace to request that lock_fs is
bypassed when suspending a device.

There's no change to the behaviour of existing code that doesn't know about
the new flag.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Alasdair G Kergon 2006-01-06 00:20:07 -08:00 committed by Linus Torvalds
parent aa8d7c2fbe
commit 6da487dcc0
2 changed files with 17 additions and 5 deletions

View File

@ -693,14 +693,18 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
static int do_suspend(struct dm_ioctl *param)
{
int r = 0;
int do_lockfs = 1;
struct mapped_device *md;
md = find_device(param);
if (!md)
return -ENXIO;
if (param->flags & DM_SKIP_LOCKFS_FLAG)
do_lockfs = 0;
if (!dm_suspended(md))
r = dm_suspend(md, 1);
r = dm_suspend(md, do_lockfs);
if (!r)
r = __dev_status(md, param);
@ -712,6 +716,7 @@ static int do_suspend(struct dm_ioctl *param)
static int do_resume(struct dm_ioctl *param)
{
int r = 0;
int do_lockfs = 1;
struct hash_cell *hc;
struct mapped_device *md;
struct dm_table *new_map;
@ -737,8 +742,10 @@ static int do_resume(struct dm_ioctl *param)
/* Do we need to load a new map ? */
if (new_map) {
/* Suspend if it isn't already suspended */
if (param->flags & DM_SKIP_LOCKFS_FLAG)
do_lockfs = 0;
if (!dm_suspended(md))
dm_suspend(md, 1);
dm_suspend(md, do_lockfs);
r = dm_swap_table(md, new_map);
if (r) {

View File

@ -272,9 +272,9 @@ typedef char ioctl_struct[308];
#define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
#define DM_VERSION_MINOR 4
#define DM_VERSION_MINOR 5
#define DM_VERSION_PATCHLEVEL 0
#define DM_VERSION_EXTRA "-ioctl (2005-01-12)"
#define DM_VERSION_EXTRA "-ioctl (2005-10-04)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
@ -301,8 +301,13 @@ typedef char ioctl_struct[308];
#define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */
/*
* Set this to improve performance when you aren't going to use open_count
* Set this to improve performance when you aren't going to use open_count.
*/
#define DM_SKIP_BDGET_FLAG (1 << 9) /* In */
/*
* Set this to avoid attempting to freeze any filesystem when suspending.
*/
#define DM_SKIP_LOCKFS_FLAG (1 << 10) /* In */
#endif /* _LINUX_DM_IOCTL_H */