1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _MEMREGION_H_ |
3 | #define _MEMREGION_H_ |
4 | #include <linux/types.h> |
5 | #include <linux/errno.h> |
6 | #include <linux/range.h> |
7 | #include <linux/bug.h> |
8 | |
9 | struct memregion_info { |
10 | int target_node; |
11 | struct range range; |
12 | }; |
13 | |
14 | #ifdef CONFIG_MEMREGION |
15 | int memregion_alloc(gfp_t gfp); |
16 | void memregion_free(int id); |
17 | #else |
18 | static inline int memregion_alloc(gfp_t gfp) |
19 | { |
20 | return -ENOMEM; |
21 | } |
22 | static inline void memregion_free(int id) |
23 | { |
24 | } |
25 | #endif |
26 | |
27 | /** |
28 | * cpu_cache_invalidate_memregion - drop any CPU cached data for |
29 | * memregions described by @res_desc |
30 | * @res_desc: one of the IORES_DESC_* types |
31 | * |
32 | * Perform cache maintenance after a memory event / operation that |
33 | * changes the contents of physical memory in a cache-incoherent manner. |
34 | * For example, device memory technologies like NVDIMM and CXL have |
35 | * device secure erase, and dynamic region provision that can replace |
36 | * the memory mapped to a given physical address. |
37 | * |
38 | * Limit the functionality to architectures that have an efficient way |
39 | * to writeback and invalidate potentially terabytes of address space at |
40 | * once. Note that this routine may or may not write back any dirty |
41 | * contents while performing the invalidation. It is only exported for |
42 | * the explicit usage of the NVDIMM and CXL modules in the 'DEVMEM' |
43 | * symbol namespace on bare platforms. |
44 | * |
45 | * Returns 0 on success or negative error code on a failure to perform |
46 | * the cache maintenance. |
47 | */ |
48 | #ifdef CONFIG_ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION |
49 | int cpu_cache_invalidate_memregion(int res_desc); |
50 | bool cpu_cache_has_invalidate_memregion(void); |
51 | #else |
52 | static inline bool cpu_cache_has_invalidate_memregion(void) |
53 | { |
54 | return false; |
55 | } |
56 | |
57 | static inline int cpu_cache_invalidate_memregion(int res_desc) |
58 | { |
59 | WARN_ON_ONCE("CPU cache invalidation required" ); |
60 | return -ENXIO; |
61 | } |
62 | #endif |
63 | #endif /* _MEMREGION_H_ */ |
64 | |