On Tue, 2016-03-08 at 14:47 -0800, Dan Williams wrote:
> 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: <[email protected]>
> Cc: Vishal Verma <[email protected]>
> Cc: Ross Zwisler <[email protected]>
> Signed-off-by: Dan Williams <[email protected]>
> ---
> arch/x86/include/asm/pmem.h | 5 +++++
> drivers/nvdimm/bus.c | 46
> +++++++++++++++++++++++++++++++++++++++++++
> drivers/nvdimm/nd.h | 2 ++
> drivers/nvdimm/pmem.c | 29 ++++++++++++++++++++++++++-
> include/linux/pmem.h | 19 ++++++++++++++++++
> 5 files changed, 100 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/pmem.h b/arch/x86/include/asm/pmem.h
> index c57fd1ea9689..bf8b35d2035a 100644
> --- a/arch/x86/include/asm/pmem.h
> +++ b/arch/x86/include/asm/pmem.h
<>
> 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 @@ static int pmem_do_bvec(struct pmem_device *pmem,
> struct page *page,
> } 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);
> + }
> }
Just noticed this -- why do we memcpy_to_pmem twice in the error case?
Sh
ouldn't it be:
if (unlikely(bad_pmem))
pmem_clear_poison(pmem, pmem_off, len);
memcpy_to_pmem(pmem_addr, mem + off, len);
