On 25.09.20 21:11, Dan Williams wrote:
> Towards removing the mode specific @dax_kmem_res attribute from the
> generic 'struct dev_dax', and preparing for multi-range support, move
> resource name tracking to driver data. The memory for the resource name
> needs to have its own lifetime separate from the device bind lifetime
> for cases where the driver is unbound, but the kmem range could not be
> unplugged from the page allocator.
>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
> Cc: Brice Goglin <Brice.Goglin@xxxxxxxx>
> Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
> Cc: Jia He <justin.he@xxxxxxx>
> Cc: Joao Martins <joao.m.martins@xxxxxxxxxx>
> Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
> drivers/dax/kmem.c | 16 +++++++++-------
> 1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
> index b0d6a99cf12d..6fe2cb1c5f7c 100644
> --- a/drivers/dax/kmem.c
> +++ b/drivers/dax/kmem.c
> @@ -34,7 +34,7 @@ int dev_dax_kmem_probe(struct device *dev)
> struct dev_dax *dev_dax = to_dev_dax(dev);
> struct range range = dax_kmem_range(dev_dax);
> struct resource *new_res;
> - const char *new_res_name;
> + char *res_name;
I wonder why that change ...
> int numa_node;
> int rc;
>
> @@ -51,15 +51,15 @@ int dev_dax_kmem_probe(struct device *dev)
> return -EINVAL;
> }
>
> - new_res_name = kstrdup(dev_name(dev), GFP_KERNEL);
> - if (!new_res_name)
> + res_name = kstrdup(dev_name(dev), GFP_KERNEL);
> + if (!res_name)
> return -ENOMEM;
>
> /* Region is permanently reserved if hotremove fails. */
> - new_res = request_mem_region(range.start, range_len(&range), new_res_name);
> + new_res = request_mem_region(range.start, range_len(&range), res_name);
> if (!new_res) {
> dev_warn(dev, "could not reserve region [%#llx-%#llx]\n", range.start, range.end);
> - kfree(new_res_name);
> + kfree(res_name);
> return -EBUSY;
> }
>
> @@ -80,9 +80,11 @@ int dev_dax_kmem_probe(struct device *dev)
> if (rc) {
> release_resource(new_res);
> kfree(new_res);
> - kfree(new_res_name);
> + kfree(res_name);
> return rc;
> }
> +
> + dev_set_drvdata(dev, res_name);
> dev_dax->dax_kmem_res = new_res;
>
> return 0;
> @@ -94,7 +96,7 @@ static int dev_dax_kmem_remove(struct device *dev)
> struct dev_dax *dev_dax = to_dev_dax(dev);
> struct range range = dax_kmem_range(dev_dax);
> struct resource *res = dev_dax->dax_kmem_res;
> - const char *res_name = res->name;
> + const char *res_name = dev_get_drvdata(dev);
... because here you're back to "const".
> int rc;
>
> /*
>
I do wonder if it wouldn't all be easier to just have some
struct {
const char *res_name;
struct resource *res;
};
allocating that and storing it as drvdata. But let's see what the next
patch brings :)
--
Thanks,
David / dhildenb
