// 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);