diff options
Diffstat (limited to 'include/linux/memregion.h')
| -rw-r--r-- | include/linux/memregion.h | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/include/linux/memregion.h b/include/linux/memregion.h index c04c4fd2e209..bf83363807ac 100644 --- a/include/linux/memregion.h +++ b/include/linux/memregion.h @@ -3,6 +3,7 @@ #define _MEMREGION_H_ #include <linux/types.h> #include <linux/errno.h> +#include <linux/bug.h> struct memregion_info { int target_node; @@ -20,4 +21,41 @@ static inline void memregion_free(int id) { } #endif + +/** + * cpu_cache_invalidate_memregion - drop any CPU cached data for + * memregions described by @res_desc + * @res_desc: one of the IORES_DESC_* types + * + * Perform cache maintenance after a memory event / operation that + * changes the contents of physical memory in a cache-incoherent manner. + * For example, device memory technologies like NVDIMM and CXL have + * device secure erase, and dynamic region provision that can replace + * the memory mapped to a given physical address. + * + * Limit the functionality to architectures that have an efficient way + * to writeback and invalidate potentially terabytes of address space at + * once. Note that this routine may or may not write back any dirty + * contents while performing the invalidation. It is only exported for + * the explicit usage of the NVDIMM and CXL modules in the 'DEVMEM' + * symbol namespace on bare platforms. + * + * Returns 0 on success or negative error code on a failure to perform + * the cache maintenance. + */ +#ifdef CONFIG_ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION +int cpu_cache_invalidate_memregion(int res_desc); +bool cpu_cache_has_invalidate_memregion(void); +#else +static inline bool cpu_cache_has_invalidate_memregion(void) +{ + return false; +} + +static inline int cpu_cache_invalidate_memregion(int res_desc) +{ + WARN_ON_ONCE("CPU cache invalidation required"); + return -ENXIO; +} +#endif #endif /* _MEMREGION_H_ */ |