Hi Jonathan,
On 9/10/2025 6:41 AM, Jonathan Cameron wrote:
On Fri, 22 Aug 2025 03:42:01 +0000
Smita Koralahalli <[email protected]> wrote:
Reworked from a patch by Alison Schofield <[email protected]>
Reintroduce Soft Reserved range into the iomem_resource tree for dax_hmem
to consume.
This restores visibility in /proc/iomem for ranges actively in use, while
avoiding the early-boot conflicts that occurred when Soft Reserved was
published into iomem before CXL window and region discovery.
Link:
https://lore.kernel.org/linux-cxl/29312c0765224ae76862d59a17748c8188fb95f1.1692638817.git.alison.schofi...@intel.com/
Co-developed-by: Alison Schofield <[email protected]>
Signed-off-by: Alison Schofield <[email protected]>
Signed-off-by: Smita Koralahalli <[email protected]>
A few trivial things inline. Not are important enough to need a change though.
Reviewed-by: Jonathan Cameron <[email protected]>
---
drivers/dax/hmem/hmem.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c
index 90978518e5f4..24a6e7e3d916 100644
--- a/drivers/dax/hmem/hmem.c
+++ b/drivers/dax/hmem/hmem.c
@@ -93,6 +93,40 @@ static void process_defer_work(struct work_struct *_work)
walk_hmem_resources(&pdev->dev, handle_deferred_cxl);
}
+static void remove_soft_reserved(void *data)
+{
+ struct resource *r = data;
+
+ remove_resource(r);
Type doesn't really help us here so why not skip the local variable.
remove_resource(data);
kfree(data);
Though I'd rename data to r.
+ kfree(r);
Fixed in v2.
+}
+
+static int add_soft_reserve_into_iomem(struct device *host,
+ const struct resource *res)
+{
+ struct resource *soft = kzalloc(sizeof(*soft), GFP_KERNEL);
+ int rc;
+
+ if (!soft)
+ return -ENOMEM;
+
+ *soft = DEFINE_RES_NAMED_DESC(res->start, (res->end - res->start + 1),
+ "Soft Reserved", IORESOURCE_MEM,
+ IORES_DESC_SOFT_RESERVED);
+
+ rc = insert_resource(&iomem_resource, soft);
+ if (rc) {
+ kfree(soft);
Could use __free() magic here and steal the pointer when you setup the
devm action below. Only a small simplification in this case, so up to
you.
Sure, I have incorporated.
+ return rc;
+ }
+
+ rc = devm_add_action_or_reset(host, remove_soft_reserved, soft);
+ if (rc)
+ return rc;
+
+ return 0;
Trivial:
return dev_add_action_or_reset(host...)
Included.
Thanks,
Smita
+}
