xref: /openbmc/linux/arch/x86/include/asm/mmu.h (revision 6c33a6f4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_MMU_H
3 #define _ASM_X86_MMU_H
4 
5 #include <linux/spinlock.h>
6 #include <linux/rwsem.h>
7 #include <linux/mutex.h>
8 #include <linux/atomic.h>
9 
10 /*
11  * x86 has arch-specific MMU state beyond what lives in mm_struct.
12  */
13 typedef struct {
14 	/*
15 	 * ctx_id uniquely identifies this mm_struct.  A ctx_id will never
16 	 * be reused, and zero is not a valid ctx_id.
17 	 */
18 	u64 ctx_id;
19 
20 	/*
21 	 * Any code that needs to do any sort of TLB flushing for this
22 	 * mm will first make its changes to the page tables, then
23 	 * increment tlb_gen, then flush.  This lets the low-level
24 	 * flushing code keep track of what needs flushing.
25 	 *
26 	 * This is not used on Xen PV.
27 	 */
28 	atomic64_t tlb_gen;
29 
30 #ifdef CONFIG_MODIFY_LDT_SYSCALL
31 	struct rw_semaphore	ldt_usr_sem;
32 	struct ldt_struct	*ldt;
33 #endif
34 
35 #ifdef CONFIG_X86_64
36 	/* True if mm supports a task running in 32 bit compatibility mode. */
37 	unsigned short ia32_compat;
38 #endif
39 
40 	struct mutex lock;
41 	void __user *vdso;			/* vdso base address */
42 	const struct vdso_image *vdso_image;	/* vdso image in use */
43 
44 	atomic_t perf_rdpmc_allowed;	/* nonzero if rdpmc is allowed */
45 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
46 	/*
47 	 * One bit per protection key says whether userspace can
48 	 * use it or not.  protected by mmap_sem.
49 	 */
50 	u16 pkey_allocation_map;
51 	s16 execute_only_pkey;
52 #endif
53 } mm_context_t;
54 
55 #define INIT_MM_CONTEXT(mm)						\
56 	.context = {							\
57 		.ctx_id = 1,						\
58 		.lock = __MUTEX_INITIALIZER(mm.context.lock),		\
59 	}
60 
61 void leave_mm(int cpu);
62 
63 #endif /* _ASM_X86_MMU_H */
64