diff mbox

[v2,2/5] dax: fallback from pmd to pte on error

Message ID 1459303190-20072-3-git-send-email-vishal.l.verma@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Verma, Vishal L March 30, 2016, 1:59 a.m. UTC 
From: Dan Williams <dan.j.williams@intel.com>

In preparation for consulting a badblocks list in pmem_direct_access(),
teach dax_pmd_fault() to fallback rather than fail immediately upon
encountering an error.  The thought being that reducing the span of the
dax request may avoid the error region.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 fs/dax.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Jeff Moyer April 15, 2016, 2:55 p.m. UTC | #1 
Vishal Verma <vishal.l.verma@intel.com> writes:

> From: Dan Williams <dan.j.williams@intel.com>
>
> In preparation for consulting a badblocks list in pmem_direct_access(),
> teach dax_pmd_fault() to fallback rather than fail immediately upon
> encountering an error.  The thought being that reducing the span of the
> dax request may avoid the error region.
>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>

> ---
>  fs/dax.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index 90322eb..ec6417b 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -945,8 +945,8 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
>  		long length = dax_map_atomic(bdev, &dax);
>  
>  		if (length < 0) {
> -			result = VM_FAULT_SIGBUS;
> -			goto out;
> +			dax_pmd_dbg(&bh, address, "dax-error fallback");
> +			goto fallback;
>  		}
>  		if (length < PMD_SIZE) {
>  			dax_pmd_dbg(&bh, address, "dax-length too small");
diff mbox

Patch

diff --git a/fs/dax.c b/fs/dax.c
index 90322eb..ec6417b 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -945,8 +945,8 @@  int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 		long length = dax_map_atomic(bdev, &dax);
 
 		if (length < 0) {
-			result = VM_FAULT_SIGBUS;
-			goto out;
+			dax_pmd_dbg(&bh, address, "dax-error fallback");
+			goto fallback;
 		}
 		if (length < PMD_SIZE) {
 			dax_pmd_dbg(&bh, address, "dax-length too small");