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| author |   Dan Williams <dan.j.williams@intel.com> | 2018-05-02 06:46:33 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2018-05-22 23:18:31 -0700 |
| commit | b3a9a0c36e1f7b9e2e6cf965c2bb973624f2b3b9 (patch) | |
| tree | 54f43a8720a29159310b112cf21e7d3a3b5dce85 /drivers/md/dm-stripe.c | |
| parent | uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation (diff) | |
| download | linux-dev-b3a9a0c36e1f7b9e2e6cf965c2bb973624f2b3b9.tar.xz linux-dev-b3a9a0c36e1f7b9e2e6cf965c2bb973624f2b3b9.zip | |
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.c | 21 |
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) |