mirror_ubuntu-kernels/include/linux/memregion.h

64 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _MEMREGION_H_
#define _MEMREGION_H_
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/range.h>
#include <linux/bug.h>
struct memregion_info {
int target_node;
struct range range;
};
#ifdef CONFIG_MEMREGION
int memregion_alloc(gfp_t gfp);
void memregion_free(int id);
#else
static inline int memregion_alloc(gfp_t gfp)
{
return -ENOMEM;
}
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_ */