dax: enable dax in the presence of known media errors (badblocks)
1/ If a mapping overlaps a bad sector fail the request.
2/ Do not opportunistically report more dax-capable capacity than is
requested when errors present.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[vishal: fix a conflict with system RAM collision patches]
[vishal: add a 'size' parameter to ->direct_access]
[vishal: fix a conflict with DAX alignment check patches]
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index f798899..c447579 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -182,14 +182,22 @@
}
static long pmem_direct_access(struct block_device *bdev, sector_t sector,
- void __pmem **kaddr, pfn_t *pfn)
+ void __pmem **kaddr, pfn_t *pfn, long size)
{
struct pmem_device *pmem = bdev->bd_disk->private_data;
resource_size_t offset = sector * 512 + pmem->data_offset;
+ if (unlikely(is_bad_pmem(&pmem->bb, sector, size)))
+ return -EIO;
*kaddr = pmem->virt_addr + offset;
*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+ /*
+ * If badblocks are present, limit known good range to the
+ * requested range.
+ */
+ if (unlikely(pmem->bb.count))
+ return size;
return pmem->size - pmem->pfn_pad - offset;
}