| Message ID | 147318057109.30325.17721163157375660986.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | a07b871 |
| Headers | show |
On Tue, Sep 6, 2016 at 9:49 AM, Dan Williams <dan.j.williams@intel.com> wrote: > In pgoff_to_phys() 'pgoff' is already relative to base of the dax > device, so we only need to compare if the current offset is within the > current resource extent. Otherwise, we are double accounting the > resource start offset when translating pgoff to a physical address. > > Cc: <stable@vger.kernel.org> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> On second look this results in the exact same translation, correct in both cases. This is also confirmed by a new ndctl unit test that does data verification by writing through a /dev/pmem device and the verifying via a /dev/dax device associated with the same namespace, so I'm dropping this patch.
diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c index 29f600f2c447..4653f84cabe7 100644 --- a/drivers/dax/dax.c +++ b/drivers/dax/dax.c @@ -357,16 +357,18 @@ static int check_vma(struct dax_dev *dax_dev, struct vm_area_struct *vma, static phys_addr_t pgoff_to_phys(struct dax_dev *dax_dev, pgoff_t pgoff, unsigned long size) { + phys_addr_t phys, offset; struct resource *res; - phys_addr_t phys; int i; + offset = pgoff * PAGE_SIZE; for (i = 0; i < dax_dev->num_resources; i++) { res = &dax_dev->res[i]; - phys = pgoff * PAGE_SIZE + res->start; - if (phys >= res->start && phys <= res->end) + if (offset < resource_size(res)) { + phys = offset + res->start; break; - pgoff -= PHYS_PFN(resource_size(res)); + } + offset -= resource_size(res); } if (i < dax_dev->num_resources) {
In pgoff_to_phys() 'pgoff' is already relative to base of the dax device, so we only need to compare if the current offset is within the current resource extent. Otherwise, we are double accounting the resource start offset when translating pgoff to a physical address. Cc: <stable@vger.kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- drivers/dax/dax.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)