xref: /linux/arch/x86/include/asm/mmu.h (revision d26270061ae66b915138af7cd73ca6f8b85e6b44)
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 #include <linux/bits.h>
10 
11 /* Uprobes on this MM assume 32-bit code */
12 #define MM_CONTEXT_UPROBE_IA32		0
13 /* vsyscall page is accessible on this MM */
14 #define MM_CONTEXT_HAS_VSYSCALL		1
15 /* Do not allow changing LAM mode */
16 #define MM_CONTEXT_LOCK_LAM		2
17 /* Allow LAM and SVA coexisting */
18 #define MM_CONTEXT_FORCE_TAGGED_SVA	3
19 
20 /*
21  * x86 has arch-specific MMU state beyond what lives in mm_struct.
22  */
23 typedef struct {
24 	/*
25 	 * ctx_id uniquely identifies this mm_struct.  A ctx_id will never
26 	 * be reused, and zero is not a valid ctx_id.
27 	 */
28 	u64 ctx_id;
29 
30 	/*
31 	 * Any code that needs to do any sort of TLB flushing for this
32 	 * mm will first make its changes to the page tables, then
33 	 * increment tlb_gen, then flush.  This lets the low-level
34 	 * flushing code keep track of what needs flushing.
35 	 *
36 	 * This is not used on Xen PV.
37 	 */
38 	atomic64_t tlb_gen;
39 
40 #ifdef CONFIG_MODIFY_LDT_SYSCALL
41 	struct rw_semaphore	ldt_usr_sem;
42 	struct ldt_struct	*ldt;
43 #endif
44 
45 #ifdef CONFIG_X86_64
46 	unsigned long flags;
47 #endif
48 
49 #ifdef CONFIG_ADDRESS_MASKING
50 	/* Active LAM mode:  X86_CR3_LAM_U48 or X86_CR3_LAM_U57 or 0 (disabled) */
51 	unsigned long lam_cr3_mask;
52 
53 	/* Significant bits of the virtual address. Excludes tag bits. */
54 	u64 untag_mask;
55 #endif
56 
57 	struct mutex lock;
58 	void __user *vdso;			/* vdso base address */
59 	const struct vdso_image *vdso_image;	/* vdso image in use */
60 
61 	atomic_t perf_rdpmc_allowed;	/* nonzero if rdpmc is allowed */
62 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
63 	/*
64 	 * One bit per protection key says whether userspace can
65 	 * use it or not.  protected by mmap_lock.
66 	 */
67 	u16 pkey_allocation_map;
68 	s16 execute_only_pkey;
69 #endif
70 } mm_context_t;
71 
72 #define INIT_MM_CONTEXT(mm)						\
73 	.context = {							\
74 		.ctx_id = 1,						\
75 		.lock = __MUTEX_INITIALIZER(mm.context.lock),		\
76 	}
77 
78 void leave_mm(int cpu);
79 #define leave_mm leave_mm
80 
81 #endif /* _ASM_X86_MMU_H */
82