| 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 | * memregion |
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| 30 | * @start: start physical address of the target memory region. |
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| 31 | * @len: length of the target memory region. -1 for all the regions of |
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| 32 | * the target type. |
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| 33 | * |
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| 34 | * Perform cache maintenance after a memory event / operation that |
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| 35 | * changes the contents of physical memory in a cache-incoherent manner. |
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| 36 | * For example, device memory technologies like NVDIMM and CXL have |
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| 37 | * device secure erase, and dynamic region provision that can replace |
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| 38 | * the memory mapped to a given physical address. |
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| 39 | * |
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| 40 | * Limit the functionality to architectures that have an efficient way |
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| 41 | * to writeback and invalidate potentially terabytes of address space at |
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| 42 | * once. Note that this routine may or may not write back any dirty |
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| 43 | * contents while performing the invalidation. It is only exported for |
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| 44 | * the explicit usage of the NVDIMM and CXL modules in the 'DEVMEM' |
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| 45 | * symbol namespace on bare platforms. |
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| 46 | * |
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| 47 | * Returns 0 on success or negative error code on a failure to perform |
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| 48 | * the cache maintenance. |
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| 49 | */ |
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| 50 | #ifdef CONFIG_ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION |
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| 51 | int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len); |
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| 52 | bool cpu_cache_has_invalidate_memregion(void); |
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| 53 | #else |
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| 54 | static inline bool cpu_cache_has_invalidate_memregion(void) |
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| 55 | { |
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| 56 | return false; |
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| 57 | } |
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| 58 | |
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| 59 | static inline int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len) |
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| 60 | { |
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| 61 | WARN_ON_ONCE("CPU cache invalidation required" ); |
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| 62 | return -ENXIO; |
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| 63 | } |
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| 64 | #endif |
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| 65 | |
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| 66 | static inline int cpu_cache_invalidate_all(void) |
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| 67 | { |
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| 68 | return cpu_cache_invalidate_memregion(start: 0, len: -1); |
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| 69 | } |
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| 70 | |
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| 71 | #endif /* _MEMREGION_H_ */ |
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| 72 | |
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