Currently pmem_clear_poison() expects offset and len to be sector aligned.
Atleast that seems to be the assumption with which code has been written.
It is called only from pmem_do_bvec() which is called only from pmem_rw_page()
and pmem_make_request() which will only passe sector aligned offset and len.
Soon we want use this function from dax_zero_page_range() code path which
can try to zero arbitrary range of memory with-in a page. So update this
function to assume that offset and length can be arbitrary and do the
necessary alignments as needed.
nvdimm_clear_poison() seems to assume offset and len to be aligned to
clear_err_unit boundary. But this is currently internal detail and is
not exported for others to use. So for now, continue to align offset and
length to SECTOR_SIZE boundary. Improving it further and to align it
to clear_err_unit boundary is a TODO item for future.
Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
---
drivers/nvdimm/pmem.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 075b11682192..e72959203253 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -74,14 +74,28 @@ static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
sector_t sector;
long cleared;
blk_status_t rc = BLK_STS_OK;
+ phys_addr_t start_aligned, end_aligned;
+ unsigned int len_aligned;
- sector = (offset - pmem->data_offset) / 512;
+ /*
+ * Callers can pass arbitrary offset and len. But nvdimm_clear_poison()
+ * expects memory offset and length to meet certain alignment
+ * restrction (clear_err_unit). Currently nvdimm does not export
+ * required alignment. So align offset and length to sector boundary
+ * before passing it to nvdimm_clear_poison().
+ */
+ start_aligned = ALIGN(offset, SECTOR_SIZE);
+ end_aligned = ALIGN_DOWN((offset + len), SECTOR_SIZE) - 1;
+ len_aligned = end_aligned - start_aligned + 1;
+
+ sector = (start_aligned - pmem->data_offset) / 512;
- cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
- if (cleared < len)
+ cleared = nvdimm_clear_poison(dev, pmem->phys_addr + start_aligned,
+ len_aligned);
+ if (cleared < len_aligned)
rc = BLK_STS_IOERR;
if (cleared > 0 && cleared / 512) {
- hwpoison_clear(pmem, pmem->phys_addr + offset, cleared);
+ hwpoison_clear(pmem, pmem->phys_addr + start_aligned, cleared);
cleared /= 512;
dev_dbg(dev, "%#llx clear %ld sector%s\n",
(unsigned long long) sector, cleared,
--
2.20.1
