diff options
Diffstat (limited to 'drivers/dax/kmem.c')
| -rw-r--r-- | drivers/dax/kmem.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 1e678bdf5aed..275aa5f87399 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -14,6 +14,11 @@ #include "dax-private.h" #include "bus.h" +/* Memory resource name used for add_memory_driver_managed(). */ +static const char *kmem_name; +/* Set if any memory will remain added when the driver will be unloaded. */ +static bool any_hotremove_failed; + int dev_dax_kmem_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); @@ -70,7 +75,12 @@ int dev_dax_kmem_probe(struct device *dev) */ new_res->flags = IORESOURCE_SYSTEM_RAM; - rc = add_memory(numa_node, new_res->start, resource_size(new_res)); + /* + * Ensure that future kexec'd kernels will not treat this as RAM + * automatically. + */ + rc = add_memory_driver_managed(numa_node, new_res->start, + resource_size(new_res), kmem_name); if (rc) { release_resource(new_res); kfree(new_res); @@ -100,6 +110,7 @@ static int dev_dax_kmem_remove(struct device *dev) */ rc = remove_memory(dev_dax->target_node, kmem_start, kmem_size); if (rc) { + any_hotremove_failed = true; dev_err(dev, "DAX region %pR cannot be hotremoved until the next reboot\n", res); @@ -124,6 +135,7 @@ static int dev_dax_kmem_remove(struct device *dev) * permanently pinned as reserved by the unreleased * request_mem_region(). */ + any_hotremove_failed = true; return 0; } #endif /* CONFIG_MEMORY_HOTREMOVE */ @@ -137,12 +149,24 @@ static struct dax_device_driver device_dax_kmem_driver = { static int __init dax_kmem_init(void) { - return dax_driver_register(&device_dax_kmem_driver); + int rc; + + /* Resource name is permanently allocated if any hotremove fails. */ + kmem_name = kstrdup_const("System RAM (kmem)", GFP_KERNEL); + if (!kmem_name) + return -ENOMEM; + + rc = dax_driver_register(&device_dax_kmem_driver); + if (rc) + kfree_const(kmem_name); + return rc; } static void __exit dax_kmem_exit(void) { dax_driver_unregister(&device_dax_kmem_driver); + if (!any_hotremove_failed) + kfree_const(kmem_name); } MODULE_AUTHOR("Intel Corporation"); |