Arrange for dm to lookup the dax services available from member
devices. Update the dax-capable targets, linear and stripe, to route dax
operations to the underlying device.
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/md/dm-linear.c | 24 ++++++++++++++++++++++++
drivers/md/dm-snap.c | 12 ++++++++++++
drivers/md/dm-stripe.c | 30 ++++++++++++++++++++++++++++++
drivers/md/dm-target.c | 11 +++++++++++
drivers/md/dm.c | 16 ++++++++++++----
include/linux/device-mapper.h | 7 +++++++
6 files changed, 96 insertions(+), 4 deletions(-)
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 4788b0b989a9..e91ca8089333 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -159,6 +159,29 @@ static long linear_direct_access(struct dm_target *ti, sector_t sector,
return ret;
}
+static long linear_dax_direct_access(struct dm_target *ti, phys_addr_t dev_addr,
+ void **kaddr, pfn_t *pfn, long size)
+{
+ struct linear_c *lc = ti->private;
+ struct block_device *bdev = lc->dev->bdev;
+ struct dax_inode *dax_inode = lc->dev->dax_inode;
+ struct blk_dax_ctl dax = {
+ .sector = linear_map_sector(ti, dev_addr >> SECTOR_SHIFT),
+ .size = size,
+ };
+ long ret;
+
+ ret = bdev_dax_direct_access(bdev, dax_inode, &dax);
+ *kaddr = dax.addr;
+ *pfn = dax.pfn;
+
+ return ret;
+}
+
+static const struct dm_dax_operations linear_dax_ops = {
+ .dm_direct_access = linear_dax_direct_access,
+};
+
static struct target_type linear_target = {
.name = "linear",
.version = {1, 3, 0},
@@ -170,6 +193,7 @@ static struct target_type linear_target = {
.prepare_ioctl = linear_prepare_ioctl,
.iterate_devices = linear_iterate_devices,
.direct_access = linear_direct_access,
+ .dax_ops = &linear_dax_ops,
};
int __init dm_linear_init(void)
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index c65feeada864..1990e3bd6958 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -2309,6 +2309,13 @@ static long origin_direct_access(struct dm_target *ti, sector_t sector,
return -EIO;
}
+static long origin_dax_direct_access(struct dm_target *ti, phys_addr_t dev_addr,
+ void **kaddr, pfn_t *pfn, long size)
+{
+ DMWARN("device does not support dax.");
+ return -EIO;
+}
+
/*
* Set the target "max_io_len" field to the minimum of all the snapshots'
* chunk sizes.
@@ -2357,6 +2364,10 @@ static int origin_iterate_devices(struct dm_target *ti,
return fn(ti, o->dev, 0, ti->len, data);
}
+static const struct dm_dax_operations origin_dax_ops = {
+ .dm_direct_access = origin_dax_direct_access,
+};
+
static struct target_type origin_target = {
.name = "snapshot-origin",
.version = {1, 9, 0},
@@ -2369,6 +2380,7 @@ static struct target_type origin_target = {
.status = origin_status,
.iterate_devices = origin_iterate_devices,
.direct_access = origin_direct_access,
+ .dax_ops = &origin_dax_ops,
};
static struct target_type snapshot_target = {
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 28193a57bf47..47fb56a6184a 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -331,6 +331,31 @@ static long stripe_direct_access(struct dm_target *ti, sector_t sector,
return ret;
}
+static long stripe_dax_direct_access(struct dm_target *ti, phys_addr_t dev_addr,
+ void **kaddr, pfn_t *pfn, long size)
+{
+ struct stripe_c *sc = ti->private;
+ uint32_t stripe;
+ struct block_device *bdev;
+ struct dax_inode *dax_inode;
+ struct blk_dax_ctl dax = {
+ .size = size,
+ };
+ long ret;
+
+ stripe_map_sector(sc, dev_addr >> SECTOR_SHIFT, &stripe, &dax.sector);
+
+ dax.sector += sc->stripe[stripe].physical_start;
+ bdev = sc->stripe[stripe].dev->bdev;
+ dax_inode = sc->stripe[stripe].dev->dax_inode;
+
+ ret = bdev_dax_direct_access(bdev, dax_inode, &dax);
+ *kaddr = dax.addr;
+ *pfn = dax.pfn;
+
+ return ret;
+}
+
/*
* Stripe status:
*
@@ -437,6 +462,10 @@ static void stripe_io_hints(struct dm_target *ti,
blk_limits_io_opt(limits, chunk_size * sc->stripes);
}
+static const struct dm_dax_operations stripe_dax_ops = {
+ .dm_direct_access = stripe_dax_direct_access,
+};
+
static struct target_type stripe_target = {
.name = "striped",
.version = {1, 6, 0},
@@ -449,6 +478,7 @@ static struct target_type stripe_target = {
.iterate_devices = stripe_iterate_devices,
.io_hints = stripe_io_hints,
.direct_access = stripe_direct_access,
+ .dax_ops = &stripe_dax_ops,
};
int __init dm_stripe_init(void)
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 710ae28fd618..ab072f53cf24 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -154,6 +154,16 @@ static long io_err_direct_access(struct dm_target *ti, sector_t sector,
return -EIO;
}
+static long io_err_dax_direct_access(struct dm_target *ti, phys_addr_t dev_addr,
+ void **kaddr, pfn_t *pfn, long size)
+{
+ return -EIO;
+}
+
+static const struct dm_dax_operations err_dax_ops = {
+ .dm_direct_access = io_err_dax_direct_access,
+};
+
static struct target_type error_target = {
.name = "error",
.version = {1, 5, 0},
@@ -165,6 +175,7 @@ static struct target_type error_target = {
.clone_and_map_rq = io_err_clone_and_map_rq,
.release_clone_rq = io_err_release_clone_rq,
.direct_access = io_err_direct_access,
+ .dax_ops = &err_dax_ops,
};
int __init dm_target_init(void)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 1b3d9253e92c..5c5eeda0eb0a 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -627,6 +627,7 @@ static int open_table_device(struct table_device *td, dev_t dev,
}
td->dm_dev.bdev = bdev;
+ td->dm_dev.dax_inode = dax_get_by_host(bdev->bd_disk->disk_name);
return 0;
}
@@ -640,7 +641,9 @@ static void close_table_device(struct table_device *td, struct mapped_device *md
bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md));
blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL);
+ put_dax_inode(td->dm_dev.dax_inode);
td->dm_dev.bdev = NULL;
+ td->dm_dev.dax_inode = NULL;
}
static struct table_device *find_table_device(struct list_head *l, dev_t dev,
@@ -907,7 +910,7 @@ 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_direct_access(struct mapped_device *md, phys_addr_t dev_addr,
- void **kaddr, pfn_t *pfn, long size)
+ void **kaddr, pfn_t *pfn, long size, bool blk)
{
sector_t sector = dev_addr >> SECTOR_SHIFT;
struct dm_table *map;
@@ -926,8 +929,11 @@ static long __dm_direct_access(struct mapped_device *md, phys_addr_t dev_addr,
len = max_io_len(sector, ti) << SECTOR_SHIFT;
size = min(len, size);
- if (ti->type->direct_access)
+ if (blk && ti->type->direct_access)
ret = ti->type->direct_access(ti, sector, kaddr, pfn, size);
+ else if (ti->type->dax_ops)
+ ret = ti->type->dax_ops->dm_direct_access(ti, dev_addr, kaddr,
+ pfn, size);
out:
dm_put_live_table(md, srcu_idx);
return min(ret, size);
@@ -938,7 +944,8 @@ static long dm_blk_direct_access(struct block_device *bdev, sector_t sector,
{
struct mapped_device *md = bdev->bd_disk->private_data;
- return __dm_direct_access(md, sector << SECTOR_SHIFT, kaddr, pfn, size);
+ return __dm_direct_access(md, sector << SECTOR_SHIFT, kaddr, pfn, size,
+ true);
}
static long dm_dax_direct_access(struct dax_inode *dax_inode,
@@ -947,7 +954,8 @@ static long dm_dax_direct_access(struct dax_inode *dax_inode,
{
struct mapped_device *md = dax_inode_get_private(dax_inode);
- return __dm_direct_access(md, dev_addr, kaddr, pfn, size);
+ return __dm_direct_access(md, dev_addr, kaddr, pfn, size,
+ false);
}
/*
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index ef7962e84444..1b64f412bb45 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -137,12 +137,18 @@ void dm_error(const char *message);
struct dm_dev {
struct block_device *bdev;
+ struct dax_inode *dax_inode;
fmode_t mode;
char name[16];
};
dev_t dm_get_dev_t(const char *path);
+struct dm_dax_operations {
+ long (*dm_direct_access)(struct dm_target *ti, phys_addr_t dev_addr,
+ void **kaddr, pfn_t *pfn, long size);
+};
+
/*
* Constructors should call these functions to ensure destination devices
* are opened/closed correctly.
@@ -180,6 +186,7 @@ struct target_type {
dm_iterate_devices_fn iterate_devices;
dm_io_hints_fn io_hints;
dm_direct_access_fn direct_access;
+ const struct dm_dax_operations *dax_ops;
/* For internal device-mapper use. */
struct list_head list;
--
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