summaryrefslogtreecommitdiff
path: root/drivers/md/dm-stripe.c
diff options
context:
space:
mode:
authorDan Williams <dan.j.williams@intel.com>2018-05-02 06:46:33 -0700
committerDan Williams <dan.j.williams@intel.com>2018-05-22 23:18:31 -0700
commitb3a9a0c36e1f7b9e2e6cf965c2bb973624f2b3b9 (patch)
tree54f43a8720a29159310b112cf21e7d3a3b5dce85 /drivers/md/dm-stripe.c
parent522239b445a2de988edb81672963708a6aaf9046 (diff)
dax: Introduce a ->copy_to_iter dax operation
Similar to the ->copy_from_iter() operation, a platform may want to deploy an architecture or device specific routine for handling reads from a dax_device like /dev/pmemX. On x86 this routine will point to a machine check safe version of copy_to_iter(). For now, add the plumbing to device-mapper and the dax core. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/md/dm-stripe.c')
-rw-r--r--drivers/md/dm-stripe.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index fe7fb9b1aec3..8547d7594338 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -354,9 +354,29 @@ static size_t stripe_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff,
return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i);
}
+static size_t stripe_dax_copy_to_iter(struct dm_target *ti, pgoff_t pgoff,
+ void *addr, size_t bytes, struct iov_iter *i)
+{
+ sector_t dev_sector, sector = pgoff * PAGE_SECTORS;
+ struct stripe_c *sc = ti->private;
+ struct dax_device *dax_dev;
+ struct block_device *bdev;
+ uint32_t stripe;
+
+ stripe_map_sector(sc, sector, &stripe, &dev_sector);
+ dev_sector += sc->stripe[stripe].physical_start;
+ dax_dev = sc->stripe[stripe].dev->dax_dev;
+ bdev = sc->stripe[stripe].dev->bdev;
+
+ if (bdev_dax_pgoff(bdev, dev_sector, ALIGN(bytes, PAGE_SIZE), &pgoff))
+ return 0;
+ return dax_copy_to_iter(dax_dev, pgoff, addr, bytes, i);
+}
+
#else
#define stripe_dax_direct_access NULL
#define stripe_dax_copy_from_iter NULL
+#define stripe_dax_copy_to_iter NULL
#endif
/*
@@ -478,6 +498,7 @@ static struct target_type stripe_target = {
.io_hints = stripe_io_hints,
.direct_access = stripe_dax_direct_access,
.dax_copy_from_iter = stripe_dax_copy_from_iter,
+ .dax_copy_to_iter = stripe_dax_copy_to_iter,
};
int __init dm_stripe_init(void)