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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/dax/hmem/device.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/dax/hmem/device.c')
-rw-r--r--drivers/dax/hmem/device.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c
new file mode 100644
index 000000000..903325aac
--- /dev/null
+++ b/drivers/dax/hmem/device.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/platform_device.h>
+#include <linux/memregion.h>
+#include <linux/module.h>
+#include <linux/dax.h>
+#include <linux/mm.h>
+
+static bool nohmem;
+module_param_named(disable, nohmem, bool, 0444);
+
+static struct resource hmem_active = {
+ .name = "HMEM devices",
+ .start = 0,
+ .end = -1,
+ .flags = IORESOURCE_MEM,
+};
+
+void hmem_register_device(int target_nid, struct resource *r)
+{
+ /* define a clean / non-busy resource for the platform device */
+ struct resource res = {
+ .start = r->start,
+ .end = r->end,
+ .flags = IORESOURCE_MEM,
+ .desc = IORES_DESC_SOFT_RESERVED,
+ };
+ struct platform_device *pdev;
+ struct memregion_info info;
+ int rc, id;
+
+ if (nohmem)
+ return;
+
+ rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
+ IORES_DESC_SOFT_RESERVED);
+ if (rc != REGION_INTERSECTS)
+ return;
+
+ id = memregion_alloc(GFP_KERNEL);
+ if (id < 0) {
+ pr_err("memregion allocation failure for %pr\n", &res);
+ return;
+ }
+
+ pdev = platform_device_alloc("hmem", id);
+ if (!pdev) {
+ pr_err("hmem device allocation failure for %pr\n", &res);
+ goto out_pdev;
+ }
+
+ if (!__request_region(&hmem_active, res.start, resource_size(&res),
+ dev_name(&pdev->dev), 0)) {
+ dev_dbg(&pdev->dev, "hmem range %pr already active\n", &res);
+ goto out_active;
+ }
+
+ pdev->dev.numa_node = numa_map_to_online_node(target_nid);
+ info = (struct memregion_info) {
+ .target_node = target_nid,
+ };
+ rc = platform_device_add_data(pdev, &info, sizeof(info));
+ if (rc < 0) {
+ pr_err("hmem memregion_info allocation failure for %pr\n", &res);
+ goto out_resource;
+ }
+
+ rc = platform_device_add_resources(pdev, &res, 1);
+ if (rc < 0) {
+ pr_err("hmem resource allocation failure for %pr\n", &res);
+ goto out_resource;
+ }
+
+ rc = platform_device_add(pdev);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "device add failed for %pr\n", &res);
+ goto out_resource;
+ }
+
+ return;
+
+out_resource:
+ __release_region(&hmem_active, res.start, resource_size(&res));
+out_active:
+ platform_device_put(pdev);
+out_pdev:
+ memregion_free(id);
+}
+
+static __init int hmem_register_one(struct resource *res, void *data)
+{
+ hmem_register_device(phys_to_target_node(res->start), res);
+
+ return 0;
+}
+
+static __init int hmem_init(void)
+{
+ walk_iomem_res_desc(IORES_DESC_SOFT_RESERVED,
+ IORESOURCE_MEM, 0, -1, NULL, hmem_register_one);
+ return 0;
+}
+
+/*
+ * As this is a fallback for address ranges unclaimed by the ACPI HMAT
+ * parsing it must be at an initcall level greater than hmat_init().
+ */
+late_initcall(hmem_init);