On Fri, 2023-02-10 at 01:07 -0800, Dan Williams wrote: > 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(-) Looks good, Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx> > > 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 >
