include/linux/execmem.h

Source file repositories/reference/linux-study-clean/include/linux/execmem.h

File Facts

System
Linux kernel
Corpus path
include/linux/execmem.h
Extension
.h
Size
6746 bytes
Lines
208
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

struct execmem_range {
	unsigned long   start;
	unsigned long   end;
	unsigned long   fallback_start;
	unsigned long   fallback_end;
	pgprot_t        pgprot;
	unsigned int	alignment;
	enum execmem_range_flags flags;
};

/**
 * struct execmem_info - architecture parameters for code allocations
 * @ranges: array of parameter sets defining architecture specific
 * parameters for executable memory allocations. The ranges that are not
 * explicitly initialized by an architecture use parameters defined for
 * @EXECMEM_DEFAULT.
 */
struct execmem_info {
	struct execmem_range	ranges[EXECMEM_TYPE_MAX];
};

/**
 * execmem_arch_setup - define parameters for allocations of executable memory
 *
 * A hook for architectures to define parameters for allocations of
 * executable memory. These parameters should be filled into the
 * @execmem_info structure.
 *
 * For architectures that do not implement this method a default set of
 * parameters will be used
 *
 * Return: a structure defining architecture parameters and restrictions
 * for allocations of executable memory
 */
struct execmem_info *execmem_arch_setup(void);

/**
 * execmem_alloc - allocate executable memory
 * @type: type of the allocation
 * @size: how many bytes of memory are required
 *
 * Allocates memory that will contain executable code, either generated or
 * loaded from kernel modules.
 *
 * Allocates memory that will contain data coupled with executable code,
 * like data sections in kernel modules.
 *
 * The memory will have protections defined by architecture for executable
 * region of the @type.
 *
 * Return: a pointer to the allocated memory or %NULL
 */
void *execmem_alloc(enum execmem_type type, size_t size);

/**
 * execmem_alloc_rw - allocate writable executable memory
 * @type: type of the allocation
 * @size: how many bytes of memory are required
 *
 * Allocates memory that will contain executable code, either generated or
 * loaded from kernel modules.
 *
 * Allocates memory that will contain data coupled with executable code,
 * like data sections in kernel modules.
 *
 * Forces writable permissions on the allocated memory and the caller is
 * responsible to manage the permissions afterwards.
 *
 * For architectures that use ROX cache the permissions will be set to R+W.
 * For architectures that don't use ROX cache the default permissions for @type
 * will be used as they must be writable.
 *
 * Return: a pointer to the allocated memory or %NULL
 */
void *execmem_alloc_rw(enum execmem_type type, size_t size);

/**
 * execmem_free - free executable memory
 * @ptr: pointer to the memory that should be freed
 */
void execmem_free(void *ptr);

DEFINE_FREE(execmem, void *, if (_T) execmem_free(_T));

#ifdef CONFIG_MMU
/**
 * execmem_vmap - create virtual mapping for EXECMEM_MODULE_DATA memory
 * @size: size of the virtual mapping in bytes
 *
 * Maps virtually contiguous area in the range suitable for EXECMEM_MODULE_DATA.

Annotation

Implementation Notes