In preparation for the CXL region driver to take over the responsibility of registering device-dax instances for CXL regions, move the registration of "hmem" devices to dax_hmem.ko. Previously the builtin component of this enabling (drivers/dax/hmem/device.o) would register platform devices for each address range and trigger the dax_hmem.ko module to load and attach device-dax instances to those devices. Now, the ranges are collected from the HMAT and EFI memory map walking, but the device creation is deferred. A new "hmem_platform" device is created which triggers dax_hmem.ko to load and register the platform devices. Tested-by: Fan Ni <fan.ni@xxxxxxxxxxx> Link: https://lore.kernel.org/r/167564543923.847146.9030380223622044744.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/acpi/numa/hmat.c | 2 - drivers/dax/Kconfig | 2 - drivers/dax/hmem/device.c | 91 +++++++++++++++++++-------------------- drivers/dax/hmem/hmem.c | 105 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 7 ++- 5 files changed, 155 insertions(+), 52 deletions(-) diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c index ff24282301ab..bba268ecd802 100644 --- a/drivers/acpi/numa/hmat.c +++ b/drivers/acpi/numa/hmat.c @@ -718,7 +718,7 @@ static void hmat_register_target_devices(struct memory_target *target) for (res = target->memregions.child; res; res = res->sibling) { int target_nid = pxm_to_node(target->memory_pxm); - hmem_register_device(target_nid, res); + hmem_register_resource(target_nid, res); } } diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig index 5fdf269a822e..d13c889c2a64 100644 --- a/drivers/dax/Kconfig +++ b/drivers/dax/Kconfig @@ -46,7 +46,7 @@ config DEV_DAX_HMEM Say M if unsure. config DEV_DAX_HMEM_DEVICES - depends on DEV_DAX_HMEM && DAX=y + depends on DEV_DAX_HMEM && DAX def_bool y config DEV_DAX_KMEM diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c index b1b339bccfe5..f9e1a76a04a9 100644 --- a/drivers/dax/hmem/device.c +++ b/drivers/dax/hmem/device.c @@ -8,6 +8,8 @@ static bool nohmem; module_param_named(disable, nohmem, bool, 0444); +static bool platform_initialized; +static DEFINE_MUTEX(hmem_resource_lock); static struct resource hmem_active = { .name = "HMEM devices", .start = 0, @@ -15,71 +17,66 @@ static struct resource hmem_active = { .flags = IORESOURCE_MEM, }; -void hmem_register_device(int target_nid, struct resource *res) +int walk_hmem_resources(struct device *host, walk_hmem_fn fn) +{ + struct resource *res; + int rc = 0; + + mutex_lock(&hmem_resource_lock); + for (res = hmem_active.child; res; res = res->sibling) { + rc = fn(host, (int) res->desc, res); + if (rc) + break; + } + mutex_unlock(&hmem_resource_lock); + return rc; +} +EXPORT_SYMBOL_GPL(walk_hmem_resources); + +static void __hmem_register_resource(int target_nid, struct resource *res) { struct platform_device *pdev; - struct memregion_info info; - int rc, id; + struct resource *new; + int rc; - if (nohmem) + new = __request_region(&hmem_active, res->start, resource_size(res), "", + 0); + if (!new) { + pr_debug("hmem range %pr already active\n", res); return; + } - rc = region_intersects(res->start, resource_size(res), IORESOURCE_MEM, - IORES_DESC_SOFT_RESERVED); - if (rc != REGION_INTERSECTS) - return; + new->desc = target_nid; - id = memregion_alloc(GFP_KERNEL); - if (id < 0) { - pr_err("memregion allocation failure for %pr\n", res); + if (platform_initialized) return; - } - pdev = platform_device_alloc("hmem", id); + pdev = platform_device_alloc("hmem_platform", 0); 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, - .range = { - .start = res->start, - .end = res->end, - }, - }; - 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; + pr_err_once("failed to register device-dax hmem_platform device\n"); + return; } rc = platform_device_add(pdev); - if (rc < 0) { - dev_err(&pdev->dev, "device add failed for %pr\n", res); - goto out_resource; - } + if (rc) + platform_device_put(pdev); + else + platform_initialized = true; +} - return; +void hmem_register_resource(int target_nid, struct resource *res) +{ + if (nohmem) + return; -out_resource: - __release_region(&hmem_active, res->start, resource_size(res)); -out_active: - platform_device_put(pdev); -out_pdev: - memregion_free(id); + mutex_lock(&hmem_resource_lock); + __hmem_register_resource(target_nid, res); + mutex_unlock(&hmem_resource_lock); } static __init int hmem_register_one(struct resource *res, void *data) { - hmem_register_device(phys_to_target_node(res->start), res); + hmem_register_resource(phys_to_target_node(res->start), res); return 0; } diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index 5025a8c9850b..e7bdff3132fa 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -3,6 +3,7 @@ #include <linux/memregion.h> #include <linux/module.h> #include <linux/pfn_t.h> +#include <linux/dax.h> #include "../bus.h" static bool region_idle; @@ -43,8 +44,110 @@ static struct platform_driver dax_hmem_driver = { }, }; -module_platform_driver(dax_hmem_driver); +static void release_memregion(void *data) +{ + memregion_free((long) data); +} + +static void release_hmem(void *pdev) +{ + platform_device_unregister(pdev); +} + +static int hmem_register_device(struct device *host, int target_nid, + const struct resource *res) +{ + struct platform_device *pdev; + struct memregion_info info; + long id; + int rc; + + rc = region_intersects(res->start, resource_size(res), IORESOURCE_MEM, + IORES_DESC_SOFT_RESERVED); + if (rc != REGION_INTERSECTS) + return 0; + + id = memregion_alloc(GFP_KERNEL); + if (id < 0) { + dev_err(host, "memregion allocation failure for %pr\n", res); + return -ENOMEM; + } + rc = devm_add_action_or_reset(host, release_memregion, (void *) id); + if (rc) + return rc; + + pdev = platform_device_alloc("hmem", id); + if (!pdev) { + dev_err(host, "device allocation failure for %pr\n", res); + return -ENOMEM; + } + + pdev->dev.numa_node = numa_map_to_online_node(target_nid); + info = (struct memregion_info) { + .target_node = target_nid, + .range = { + .start = res->start, + .end = res->end, + }, + }; + rc = platform_device_add_data(pdev, &info, sizeof(info)); + if (rc < 0) { + dev_err(host, "memregion_info allocation failure for %pr\n", + res); + goto out_put; + } + + rc = platform_device_add(pdev); + if (rc < 0) { + dev_err(host, "%s add failed for %pr\n", dev_name(&pdev->dev), + res); + goto out_put; + } + + return devm_add_action_or_reset(host, release_hmem, pdev); + +out_put: + platform_device_put(pdev); + return rc; +} + +static int dax_hmem_platform_probe(struct platform_device *pdev) +{ + return walk_hmem_resources(&pdev->dev, hmem_register_device); +} + +static struct platform_driver dax_hmem_platform_driver = { + .probe = dax_hmem_platform_probe, + .driver = { + .name = "hmem_platform", + }, +}; + +static __init int dax_hmem_init(void) +{ + int rc; + + rc = platform_driver_register(&dax_hmem_platform_driver); + if (rc) + return rc; + + rc = platform_driver_register(&dax_hmem_driver); + if (rc) + platform_driver_unregister(&dax_hmem_platform_driver); + + return rc; +} + +static __exit void dax_hmem_exit(void) +{ + platform_driver_unregister(&dax_hmem_driver); + platform_driver_unregister(&dax_hmem_platform_driver); +} + +module_init(dax_hmem_init); +module_exit(dax_hmem_exit); MODULE_ALIAS("platform:hmem*"); +MODULE_ALIAS("platform:hmem_platform*"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Intel Corporation"); diff --git a/include/linux/dax.h b/include/linux/dax.h index 2b5ecb591059..bf6258472e49 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -262,11 +262,14 @@ static inline bool dax_mapping(struct address_space *mapping) } #ifdef CONFIG_DEV_DAX_HMEM_DEVICES -void hmem_register_device(int target_nid, struct resource *r); +void hmem_register_resource(int target_nid, struct resource *r); #else -static inline void hmem_register_device(int target_nid, struct resource *r) +static inline void hmem_register_resource(int target_nid, struct resource *r) { } #endif +typedef int (*walk_hmem_fn)(struct device *dev, int target_nid, + const struct resource *res); +int walk_hmem_resources(struct device *dev, walk_hmem_fn fn); #endif
