libnvdimm, pmem: clear poison on write
If a write is directed at a known bad block perform the following:
1/ write the data
2/ send a clear poison command
3/ invalidate the poison out of the cache hierarchy
Cc: <x86@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index e7b86a7..adc3872 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -62,17 +62,40 @@
return false;
}
+static void pmem_clear_poison(struct pmem_device *pmem, phys_addr_t offset,
+ unsigned int len)
+{
+ struct device *dev = disk_to_dev(pmem->pmem_disk);
+ sector_t sector;
+ long cleared;
+
+ sector = (offset - pmem->data_offset) / 512;
+ cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
+
+ if (cleared > 0 && cleared / 512) {
+ dev_dbg(dev, "%s: %llx clear %ld sector%s\n",
+ __func__, (unsigned long long) sector,
+ cleared / 512, cleared / 512 > 1 ? "s" : "");
+ badblocks_clear(&pmem->bb, sector, cleared / 512);
+ }
+ invalidate_pmem(pmem->virt_addr + offset, len);
+}
+
static int pmem_do_bvec(struct pmem_device *pmem, struct page *page,
unsigned int len, unsigned int off, int rw,
sector_t sector)
{
int rc = 0;
+ bool bad_pmem = false;
void *mem = kmap_atomic(page);
phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
void __pmem *pmem_addr = pmem->virt_addr + pmem_off;
+ if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
+ bad_pmem = true;
+
if (rw == READ) {
- if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
+ if (unlikely(bad_pmem))
rc = -EIO;
else {
memcpy_from_pmem(mem + off, pmem_addr, len);
@@ -81,6 +104,10 @@
} else {
flush_dcache_page(page);
memcpy_to_pmem(pmem_addr, mem + off, len);
+ if (unlikely(bad_pmem)) {
+ pmem_clear_poison(pmem, pmem_off, len);
+ memcpy_to_pmem(pmem_addr, mem + off, len);
+ }
}
kunmap_atomic(mem);