arch/powerpc/include/asm/pkeys.h

Source file repositories/reference/linux-study-clean/arch/powerpc/include/asm/pkeys.h

File Facts

System
Linux kernel
Corpus path
arch/powerpc/include/asm/pkeys.h
Extension
.h
Size
4218 bytes
Lines
171
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _ASM_POWERPC_KEYS_H
#define _ASM_POWERPC_KEYS_H

#include <linux/jump_label.h>
#include <asm/firmware.h>

extern int num_pkey;
extern u32 reserved_allocation_mask; /* bits set for reserved keys */

#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
			    VM_PKEY_BIT3 | VM_PKEY_BIT4)

/* Override any generic PKEY permission defines */
#define PKEY_DISABLE_EXECUTE   0x4
#define PKEY_ACCESS_MASK       (PKEY_DISABLE_ACCESS | \
				PKEY_DISABLE_WRITE  | \
				PKEY_DISABLE_EXECUTE)

#ifdef CONFIG_PPC_BOOK3S_64
#include <asm/book3s/64/pkeys.h>
#else
#error "Not supported"
#endif


static inline vm_flags_t pkey_to_vmflag_bits(u16 pkey)
{
	return (((vm_flags_t)pkey << VM_PKEY_SHIFT) & ARCH_VM_PKEY_FLAGS);
}

static inline int vma_pkey(struct vm_area_struct *vma)
{
	if (!mmu_has_feature(MMU_FTR_PKEY))
		return 0;
	return (vma->vm_flags & ARCH_VM_PKEY_FLAGS) >> VM_PKEY_SHIFT;
}

static inline int arch_max_pkey(void)
{
	return num_pkey;
}

#define pkey_alloc_mask(pkey) (0x1 << pkey)

#define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map)

#define __mm_pkey_allocated(mm, pkey) {	\
	mm_pkey_allocation_map(mm) |= pkey_alloc_mask(pkey); \
}

#define __mm_pkey_free(mm, pkey) {	\
	mm_pkey_allocation_map(mm) &= ~pkey_alloc_mask(pkey);	\
}

#define __mm_pkey_is_allocated(mm, pkey)	\
	(mm_pkey_allocation_map(mm) & pkey_alloc_mask(pkey))

#define __mm_pkey_is_reserved(pkey) (reserved_allocation_mask & \
				       pkey_alloc_mask(pkey))

static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
{
	if (pkey < 0 || pkey >= arch_max_pkey())
		return false;

	/* Reserved keys are never allocated. */
	if (__mm_pkey_is_reserved(pkey))
		return false;

	return __mm_pkey_is_allocated(mm, pkey);
}

/*
 * Returns a positive, 5-bit key on success, or -1 on failure.
 * Relies on the mmap_lock to protect against concurrency in mm_pkey_alloc() and
 * mm_pkey_free().
 */
static inline int mm_pkey_alloc(struct mm_struct *mm)
{
	/*
	 * Note: this is the one and only place we make sure that the pkey is
	 * valid as far as the hardware is concerned. The rest of the kernel
	 * trusts that only good, valid pkeys come out of here.
	 */
	u32 all_pkeys_mask = (u32)(~(0x0));
	int ret;

	if (!mmu_has_feature(MMU_FTR_PKEY))
		return -1;
	/*

Annotation

Implementation Notes