Commit 82bf1037 authored by Dave Jiang's avatar Dave Jiang Committed by Dan Williams
Browse files

libnvdimm: check and clear poison before writing to pmem 



We need to clear any poison when we are writing to pmem. The granularity
will be sector size. If it's less then we can't do anything about it
barring corruption.

Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
Reviewed-by: default avatarVishal Verma <vishal.l.verma@intel.com>
[djbw: fixup 0-length write request to succeed]
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent dafb1048

drivers/nvdimm/claim.c

+26 −4
Original line number Diff line number Diff line
@@ -226,6 +226,12 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns, 
		resource_size_t offset, void *buf, size_t size, int rw)

{

	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);

	unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);

	sector_t sector = offset >> 9;

	int rc = 0;



	if (unlikely(!size))

		return 0;



	if (unlikely(offset + size > nsio->size)) {

		dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
@@ -233,17 +239,33 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns, 
	}



	if (rw == READ) {

		unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);



		if (unlikely(is_bad_pmem(&nsio->bb, offset / 512, sz_align)))

		if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align)))

			return -EIO;

		return memcpy_from_pmem(buf, nsio->addr + offset, size);

	} else {



		if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {

			if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)) {

				long cleared;



				cleared = nvdimm_clear_poison(&ndns->dev,

							      offset, size);

				if (cleared != size) {

					size = cleared;

					rc = -EIO;

				}



				badblocks_clear(&nsio->bb, sector,

						cleared >> 9);

			} else

				rc = -EIO;

		}



		memcpy_to_pmem(nsio->addr + offset, buf, size);

		nvdimm_flush(to_nd_region(ndns->dev.parent));

	}



	return 0;

	return rc;

}



int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio)

CRA Git | Maintained and supported by SUSTech CRA and CCSE