dax: check resource alignment at dax region/device create

All the extents of a dax-device must match the alignment of the region.
Otherwise, we are unable to guarantee fault semantics of a given page
size.  The region must be self-consistent itself as well.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2016-07-19 16:17:58 -07:00
parent 9dc1e4927b
commit 9d2d01a031

View File

@ -206,8 +206,11 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
{
struct dax_region *dax_region;
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
if (!IS_ALIGNED(res->start, align)
|| !IS_ALIGNED(resource_size(res), align))
return NULL;
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
if (!dax_region)
return NULL;
@ -560,15 +563,29 @@ int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
{
struct device *parent = dax_region->dev;
struct dax_dev *dax_dev;
int rc = 0, minor, i;
struct device *dev;
struct cdev *cdev;
int rc, minor;
dev_t dev_t;
dax_dev = kzalloc(sizeof(*dax_dev) + sizeof(*res) * count, GFP_KERNEL);
if (!dax_dev)
return -ENOMEM;
for (i = 0; i < count; i++) {
if (!IS_ALIGNED(res[i].start, dax_region->align)
|| !IS_ALIGNED(resource_size(&res[i]),
dax_region->align)) {
rc = -EINVAL;
break;
}
dax_dev->res[i].start = res[i].start;
dax_dev->res[i].end = res[i].end;
}
if (i < count)
goto err_id;
dax_dev->id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
if (dax_dev->id < 0) {
rc = dax_dev->id;
@ -601,7 +618,6 @@ int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
goto err_cdev;
/* from here on we're committed to teardown via dax_dev_release() */
memcpy(dax_dev->res, res, sizeof(*res) * count);
dax_dev->num_resources = count;
dax_dev->alive = true;
dax_dev->region = dax_region;