[PATCH] dm store geometry

Allow drive geometry to be stored with a new DM_DEV_SET_GEOMETRY ioctl.
Device-mapper will now respond to HDIO_GETGEO.  If the geometry information is
not available, zero will be returned for all of the parameters.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
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:
Darrick J. Wong 2006-03-27 01:17:54 -08:00 committed by Linus Torvalds
parent 1134e5ae79
commit 3ac51e741a
5 changed files with 121 additions and 3 deletions

View File

@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/dm-ioctl.h>
#include <linux/hdreg.h>
#include <asm/uaccess.h>
@ -700,6 +701,54 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
return dm_hash_rename(param->name, new_name);
}
static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
{
int r = -EINVAL, x;
struct mapped_device *md;
struct hd_geometry geometry;
unsigned long indata[4];
char *geostr = (char *) param + param->data_start;
md = find_device(param);
if (!md)
return -ENXIO;
if (geostr < (char *) (param + 1) ||
invalid_str(geostr, (void *) param + param_size)) {
DMWARN("Invalid geometry supplied.");
goto out;
}
x = sscanf(geostr, "%lu %lu %lu %lu", indata,
indata + 1, indata + 2, indata + 3);
if (x != 4) {
DMWARN("Unable to interpret geometry settings.");
goto out;
}
if (indata[0] > 65535 || indata[1] > 255 ||
indata[2] > 255 || indata[3] > ULONG_MAX) {
DMWARN("Geometry exceeds range limits.");
goto out;
}
geometry.cylinders = indata[0];
geometry.heads = indata[1];
geometry.sectors = indata[2];
geometry.start = indata[3];
r = dm_set_geometry(md, &geometry);
if (!r)
r = __dev_status(md, param);
param->data_size = 0;
out:
dm_put(md);
return r;
}
static int do_suspend(struct dm_ioctl *param)
{
int r = 0;
@ -1234,7 +1283,8 @@ static ioctl_fn lookup_ioctl(unsigned int cmd)
{DM_LIST_VERSIONS_CMD, list_versions},
{DM_TARGET_MSG_CMD, target_message}
{DM_TARGET_MSG_CMD, target_message},
{DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
};
return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;

View File

@ -17,6 +17,7 @@
#include <linux/mempool.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/hdreg.h>
#include <linux/blktrace_api.h>
static const char *_name = DM_NAME;
@ -102,6 +103,9 @@ struct mapped_device {
*/
struct super_block *frozen_sb;
struct block_device *suspended_bdev;
/* forced geometry settings */
struct hd_geometry geometry;
};
#define MIN_IOS 256
@ -227,6 +231,13 @@ static int dm_blk_close(struct inode *inode, struct file *file)
return 0;
}
static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct mapped_device *md = bdev->bd_disk->private_data;
return dm_get_geometry(md, geo);
}
static inline struct dm_io *alloc_io(struct mapped_device *md)
{
return mempool_alloc(md->io_pool, GFP_NOIO);
@ -313,6 +324,33 @@ struct dm_table *dm_get_table(struct mapped_device *md)
return t;
}
/*
* Get the geometry associated with a dm device
*/
int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo)
{
*geo = md->geometry;
return 0;
}
/*
* Set the geometry of a device.
*/
int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo)
{
sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors;
if (geo->start > sz) {
DMWARN("Start sector is beyond the geometry limits.");
return -EINVAL;
}
md->geometry = *geo;
return 0;
}
/*-----------------------------------------------------------------
* CRUD START:
* A more elegant soln is in the works that uses the queue
@ -906,6 +944,13 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
sector_t size;
size = dm_table_get_size(t);
/*
* Wipe any geometry if the size of the table changed.
*/
if (size != get_capacity(md->disk))
memset(&md->geometry, 0, sizeof(md->geometry));
__set_size(md, size);
if (size == 0)
return 0;
@ -1261,6 +1306,7 @@ int dm_suspended(struct mapped_device *md)
static struct block_device_operations dm_blk_dops = {
.open = dm_blk_open,
.release = dm_blk_close,
.getgeo = dm_blk_getgeo,
.owner = THIS_MODULE
};

View File

@ -14,6 +14,7 @@
#include <linux/device-mapper.h>
#include <linux/list.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#define DM_NAME "device-mapper"
#define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x)
@ -85,6 +86,12 @@ int dm_wait_event(struct mapped_device *md, int event_nr);
struct gendisk *dm_disk(struct mapped_device *md);
int dm_suspended(struct mapped_device *md);
/*
* Geometry functions.
*/
int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo);
int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo);
/*-----------------------------------------------------------------
* Functions for manipulating a table. Tables are also reference
* counted.

View File

@ -140,6 +140,7 @@ COMPATIBLE_IOCTL(DM_TABLE_DEPS_32)
COMPATIBLE_IOCTL(DM_TABLE_STATUS_32)
COMPATIBLE_IOCTL(DM_LIST_VERSIONS_32)
COMPATIBLE_IOCTL(DM_TARGET_MSG_32)
COMPATIBLE_IOCTL(DM_DEV_SET_GEOMETRY_32)
COMPATIBLE_IOCTL(DM_VERSION)
COMPATIBLE_IOCTL(DM_REMOVE_ALL)
COMPATIBLE_IOCTL(DM_LIST_DEVICES)
@ -155,6 +156,7 @@ COMPATIBLE_IOCTL(DM_TABLE_DEPS)
COMPATIBLE_IOCTL(DM_TABLE_STATUS)
COMPATIBLE_IOCTL(DM_LIST_VERSIONS)
COMPATIBLE_IOCTL(DM_TARGET_MSG)
COMPATIBLE_IOCTL(DM_DEV_SET_GEOMETRY)
/* Big K */
COMPATIBLE_IOCTL(PIO_FONT)
COMPATIBLE_IOCTL(GIO_FONT)

View File

@ -80,6 +80,16 @@
*
* DM_TARGET_MSG:
* Pass a message string to the target at a specific offset of a device.
*
* DM_DEV_SET_GEOMETRY:
* Set the geometry of a device by passing in a string in this format:
*
* "cylinders heads sectors_per_track start_sector"
*
* Beware that CHS geometry is nearly obsolete and only provided
* for compatibility with dm devices that can be booted by a PC
* BIOS. See struct hd_geometry for range limits. Also note that
* the geometry is erased if the device size changes.
*/
/*
@ -218,6 +228,7 @@ enum {
/* Added later */
DM_LIST_VERSIONS_CMD,
DM_TARGET_MSG_CMD,
DM_DEV_SET_GEOMETRY_CMD
};
/*
@ -247,6 +258,7 @@ typedef char ioctl_struct[308];
#define DM_TABLE_STATUS_32 _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, ioctl_struct)
#define DM_LIST_VERSIONS_32 _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, ioctl_struct)
#define DM_TARGET_MSG_32 _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, ioctl_struct)
#define DM_DEV_SET_GEOMETRY_32 _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, ioctl_struct)
#endif
#define DM_IOCTL 0xfd
@ -270,11 +282,12 @@ typedef char ioctl_struct[308];
#define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl)
#define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl)
#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 5
#define DM_VERSION_MINOR 6
#define DM_VERSION_PATCHLEVEL 0
#define DM_VERSION_EXTRA "-ioctl (2005-10-04)"
#define DM_VERSION_EXTRA "-ioctl (2006-02-17)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */