From: Mike Snitzer <[email protected]> [BF: Condensed to single function.]
Signed-off-by: Mike Snitzer <[email protected]> --- drivers/md/dm.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/device-mapper.h | 5 +++++ 2 files changed, 46 insertions(+) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index be49057..8f95e78 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -664,6 +664,46 @@ out: return r; } +/* + * FIXME: factor out common helper that can be used by + * multiple block_device_operations -> target methods + * (including dm_blk_ioctl above) + */ + +static int dm_blk_reserve_space(struct block_device *bdev, int mode, + sector_t offset, sector_t len, sector_t *res) +{ + struct mapped_device *md = bdev->bd_disk->private_data; + int srcu_idx; + struct dm_table *map; + struct dm_target *tgt; + int r = -EINVAL; + + map = dm_get_live_table(md, &srcu_idx); + + 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 (!tgt->type->reserve_space) + goto out; + + if (dm_suspended_md(md)) { + r = -EAGAIN; + goto out; + } + + r = tgt->type->reserve_space(tgt, mode, offset, len, res); +out: + dm_put_live_table(md, srcu_idx); + + return r; +} + static struct dm_io *alloc_io(struct mapped_device *md) { return mempool_alloc(md->io_pool, GFP_NOIO); @@ -3723,6 +3763,7 @@ static const struct block_device_operations dm_blk_dops = { .ioctl = dm_blk_ioctl, .getgeo = dm_blk_getgeo, .pr_ops = &dm_pr_ops, + .reserve_space = dm_blk_reserve_space, .owner = THIS_MODULE }; diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 0830c9e..b4825db 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -116,6 +116,10 @@ typedef void (*dm_io_hints_fn) (struct dm_target *ti, */ typedef int (*dm_busy_fn) (struct dm_target *ti); +typedef int (*dm_reserve_space_fn) (struct dm_target *ti, int mode, + sector_t offset, sector_t len, + sector_t *res); + void dm_error(const char *message); struct dm_dev { @@ -162,6 +166,7 @@ struct target_type { dm_busy_fn busy; dm_iterate_devices_fn iterate_devices; dm_io_hints_fn io_hints; + dm_reserve_space_fn reserve_space; /* For internal device-mapper use. */ struct list_head list; -- 2.4.11 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
