Commit aa129a22 authored by Milan Broz's avatar Milan Broz Committed by Linus Torvalds
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[PATCH] dm: support ioctls on mapped devices



Extend the core device-mapper infrastructure to accept arbitrary ioctls on a
mapped device provided that it has exactly one target and it is capable of
supporting ioctls.

[We can't use unlocked_ioctl because we need 'inode': 'file' might be NULL.
Is it worth changing this?]
Signed-off-by: default avatarMilan Broz <mbroz@redhat.com>
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>

Arnd Bergmann <arnd@arndb.de> wrote:

> Am Wednesday 21 June 2006 21:31 schrieb Alasdair G Kergon:
> > static struct block_device_operations dm_blk_dops = {
> > .open = dm_blk_open,
> > .release = dm_blk_close,
> > +.ioctl = dm_blk_ioctl,
> > .getgeo = dm_blk_getgeo,
> > .owner = THIS_MODULE
>
> I guess this also needs a ->compat_ioctl method, otherwise it won't
> work for ioctl numbers that have a compat_ioctl implementation in the
> low-level device driver.
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 70abac6e
......@@ -20,6 +20,7 @@
#include <linux/idr.h>
#include <linux/hdreg.h>
#include <linux/blktrace_api.h>
#include <linux/smp_lock.h>
#define DM_MSG_PREFIX "core"
......@@ -288,6 +289,45 @@ static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
return dm_get_geometry(md, geo);
}
static int dm_blk_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct mapped_device *md;
struct dm_table *map;
struct dm_target *tgt;
int r = -ENOTTY;
/* We don't really need this lock, but we do need 'inode'. */
unlock_kernel();
md = inode->i_bdev->bd_disk->private_data;
map = dm_get_table(md);
if (!map || !dm_table_get_size(map))
goto out;
/* We only support devices that have a single target */
if (dm_table_get_num_targets(map) != 1)
goto out;
tgt = dm_table_get_target(map, 0);
if (dm_suspended(md)) {
r = -EAGAIN;
goto out;
}
if (tgt->type->ioctl)
r = tgt->type->ioctl(tgt, inode, file, cmd, arg);
out:
dm_table_put(map);
lock_kernel();
return r;
}
static inline struct dm_io *alloc_io(struct mapped_device *md)
{
return mempool_alloc(md->io_pool, GFP_NOIO);
......@@ -1377,6 +1417,7 @@ int dm_suspended(struct mapped_device *md)
static struct block_device_operations dm_blk_dops = {
.open = dm_blk_open,
.release = dm_blk_close,
.ioctl = dm_blk_ioctl,
.getgeo = dm_blk_getgeo,
.owner = THIS_MODULE
};
......
......@@ -64,6 +64,10 @@ typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);
typedef int (*dm_ioctl_fn) (struct dm_target *ti, struct inode *inode,
struct file *filp, unsigned int cmd,
unsigned long arg);
void dm_error(const char *message);
/*
......@@ -91,6 +95,7 @@ struct target_type {
dm_resume_fn resume;
dm_status_fn status;
dm_message_fn message;
dm_ioctl_fn ioctl;
};
struct io_restrictions {
......
......@@ -285,7 +285,7 @@ typedef char ioctl_struct[308];
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
#define DM_VERSION_MINOR 7
#define DM_VERSION_MINOR 8
#define DM_VERSION_PATCHLEVEL 0
#define DM_VERSION_EXTRA "-ioctl (2006-06-24)"
......
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