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