diff options
| -rw-r--r-- | drivers/md/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/md/dm-core.h | 1 | ||||
| -rw-r--r-- | drivers/md/dm.c | 84 | ||||
| -rw-r--r-- | include/linux/device-mapper.h | 1 |
4 files changed, 73 insertions, 14 deletions
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index b7767da50c26..1de8372d9459 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -200,6 +200,7 @@ config BLK_DEV_DM_BUILTIN config BLK_DEV_DM tristate "Device mapper support" select BLK_DEV_DM_BUILTIN + select DAX ---help--- Device-mapper is a low level volume manager. It works by allowing people to specify mappings for ranges of logical sectors. Various diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index 136fda3ff9e5..538630190f66 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -58,6 +58,7 @@ struct mapped_device { struct target_type *immutable_target_type; struct gendisk *disk; + struct dax_device *dax_dev; char name[16]; void *interface_ptr; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index dfb75979e455..bd56dfe43a99 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -16,6 +16,7 @@ #include <linux/blkpg.h> #include <linux/bio.h> #include <linux/mempool.h> +#include <linux/dax.h> #include <linux/slab.h> #include <linux/idr.h> #include <linux/hdreg.h> @@ -908,31 +909,68 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) } EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); -static long dm_blk_direct_access(struct block_device *bdev, sector_t sector, - void **kaddr, pfn_t *pfn, long size) +static struct dm_target *dm_dax_get_live_target(struct mapped_device *md, + sector_t sector, int *srcu_idx) { - struct mapped_device *md = bdev->bd_disk->private_data; struct dm_table *map; struct dm_target *ti; - int srcu_idx; - long len, ret = -EIO; - map = dm_get_live_table(md, &srcu_idx); + map = dm_get_live_table(md, srcu_idx); if (!map) - goto out; + return NULL; ti = dm_table_find_target(map, sector); if (!dm_target_is_valid(ti)) - goto out; + return NULL; - len = max_io_len(sector, ti) << SECTOR_SHIFT; - size = min(len, size); + return ti; +} - if (ti->type->direct_access) - ret = ti->type->direct_access(ti, sector, kaddr, pfn, size); -out: +static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, + long nr_pages, void **kaddr, pfn_t *pfn) +{ + struct mapped_device *md = dax_get_private(dax_dev); + sector_t sector = pgoff * PAGE_SECTORS; + struct dm_target *ti; + long len, ret = -EIO; + int srcu_idx; + + ti = dm_dax_get_live_target(md, sector, &srcu_idx); + + if (!ti) + goto out; + if (!ti->type->direct_access) + goto out; + len = max_io_len(sector, ti) / PAGE_SECTORS; + if (len < 1) + goto out; + nr_pages = min(len, nr_pages); + if (ti->type->direct_access) { + ret = ti->type->direct_access(ti, sector, kaddr, pfn, + nr_pages * PAGE_SIZE); + /* + * FIXME: convert ti->type->direct_access to return + * nr_pages directly. + */ + if (ret >= 0) + ret /= PAGE_SIZE; + } + out: dm_put_live_table(md, srcu_idx); - return min(ret, size); + + return ret; +} + +static long dm_blk_direct_access(struct block_device *bdev, sector_t sector, + void **kaddr, pfn_t *pfn, long size) +{ + struct mapped_device *md = bdev->bd_disk->private_data; + struct dax_device *dax_dev = md->dax_dev; + long nr_pages = size / PAGE_SIZE; + + nr_pages = dm_dax_direct_access(dax_dev, sector / PAGE_SECTORS, + nr_pages, kaddr, pfn); + return nr_pages < 0 ? nr_pages : nr_pages * PAGE_SIZE; } /* @@ -1437,6 +1475,7 @@ static int next_free_minor(int *minor) } static const struct block_device_operations dm_blk_dops; +static const struct dax_operations dm_dax_ops; static void dm_wq_work(struct work_struct *work); @@ -1483,6 +1522,12 @@ static void cleanup_mapped_device(struct mapped_device *md) if (md->bs) bioset_free(md->bs); + if (md->dax_dev) { + kill_dax(md->dax_dev); + put_dax(md->dax_dev); + md->dax_dev = NULL; + } + if (md->disk) { spin_lock(&_minor_lock); md->disk->private_data = NULL; @@ -1510,6 +1555,7 @@ static void cleanup_mapped_device(struct mapped_device *md) static struct mapped_device *alloc_dev(int minor) { int r, numa_node_id = dm_get_numa_node(); + struct dax_device *dax_dev; struct mapped_device *md; void *old_md; @@ -1574,6 +1620,12 @@ static struct mapped_device *alloc_dev(int minor) md->disk->queue = md->queue; md->disk->private_data = md; sprintf(md->disk->disk_name, "dm-%d", minor); + + dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); + if (!dax_dev) + goto bad; + md->dax_dev = dax_dev; + add_disk(md->disk); format_dev_t(md->name, MKDEV(_major, minor)); @@ -2781,6 +2833,10 @@ static const struct block_device_operations dm_blk_dops = { .owner = THIS_MODULE }; +static const struct dax_operations dm_dax_ops = { + .direct_access = dm_dax_direct_access, +}; + /* * module hooks */ diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index a7e6903866fd..bcba4d89089c 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -130,6 +130,7 @@ typedef int (*dm_busy_fn) (struct dm_target *ti); */ typedef long (*dm_direct_access_fn) (struct dm_target *ti, sector_t sector, void **kaddr, pfn_t *pfn, long size); +#define PAGE_SECTORS (PAGE_SIZE / 512) void dm_error(const char *message); |