xref: /openbmc/linux/arch/s390/include/asm/tlbflush.h (revision 5a244f48)
1 #ifndef _S390_TLBFLUSH_H
2 #define _S390_TLBFLUSH_H
3 
4 #include <linux/mm.h>
5 #include <linux/sched.h>
6 #include <asm/processor.h>
7 #include <asm/pgalloc.h>
8 #include <asm/pgtable.h>
9 
10 /*
11  * Flush all TLB entries on the local CPU.
12  */
13 static inline void __tlb_flush_local(void)
14 {
15 	asm volatile("ptlb" : : : "memory");
16 }
17 
18 /*
19  * Flush TLB entries for a specific ASCE on all CPUs
20  */
21 static inline void __tlb_flush_idte(unsigned long asce)
22 {
23 	unsigned long opt;
24 
25 	opt = IDTE_PTOA;
26 	if (MACHINE_HAS_TLB_GUEST)
27 		opt |= IDTE_GUEST_ASCE;
28 	/* Global TLB flush for the mm */
29 	asm volatile(
30 		"	.insn	rrf,0xb98e0000,0,%0,%1,0"
31 		: : "a" (opt), "a" (asce) : "cc");
32 }
33 
34 #ifdef CONFIG_SMP
35 void smp_ptlb_all(void);
36 
37 /*
38  * Flush all TLB entries on all CPUs.
39  */
40 static inline void __tlb_flush_global(void)
41 {
42 	unsigned int dummy = 0;
43 
44 	csp(&dummy, 0, 0);
45 }
46 
47 /*
48  * Flush TLB entries for a specific mm on all CPUs (in case gmap is used
49  * this implicates multiple ASCEs!).
50  */
51 static inline void __tlb_flush_mm(struct mm_struct *mm)
52 {
53 	unsigned long gmap_asce;
54 
55 	/*
56 	 * If the machine has IDTE we prefer to do a per mm flush
57 	 * on all cpus instead of doing a local flush if the mm
58 	 * only ran on the local cpu.
59 	 */
60 	preempt_disable();
61 	atomic_inc(&mm->context.flush_count);
62 	/* Reset TLB flush mask */
63 	cpumask_copy(mm_cpumask(mm), &mm->context.cpu_attach_mask);
64 	barrier();
65 	gmap_asce = READ_ONCE(mm->context.gmap_asce);
66 	if (MACHINE_HAS_IDTE && gmap_asce != -1UL) {
67 		if (gmap_asce)
68 			__tlb_flush_idte(gmap_asce);
69 		__tlb_flush_idte(mm->context.asce);
70 	} else {
71 		/* Global TLB flush */
72 		__tlb_flush_global();
73 	}
74 	atomic_dec(&mm->context.flush_count);
75 	preempt_enable();
76 }
77 
78 static inline void __tlb_flush_kernel(void)
79 {
80 	if (MACHINE_HAS_IDTE)
81 		__tlb_flush_idte(init_mm.context.asce);
82 	else
83 		__tlb_flush_global();
84 }
85 #else
86 #define __tlb_flush_global()	__tlb_flush_local()
87 
88 /*
89  * Flush TLB entries for a specific ASCE on all CPUs.
90  */
91 static inline void __tlb_flush_mm(struct mm_struct *mm)
92 {
93 	__tlb_flush_local();
94 }
95 
96 static inline void __tlb_flush_kernel(void)
97 {
98 	__tlb_flush_local();
99 }
100 #endif
101 
102 static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
103 {
104 	spin_lock(&mm->context.lock);
105 	if (mm->context.flush_mm) {
106 		mm->context.flush_mm = 0;
107 		__tlb_flush_mm(mm);
108 	}
109 	spin_unlock(&mm->context.lock);
110 }
111 
112 /*
113  * TLB flushing:
114  *  flush_tlb() - flushes the current mm struct TLBs
115  *  flush_tlb_all() - flushes all processes TLBs
116  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
117  *  flush_tlb_page(vma, vmaddr) - flushes one page
118  *  flush_tlb_range(vma, start, end) - flushes a range of pages
119  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
120  */
121 
122 /*
123  * flush_tlb_mm goes together with ptep_set_wrprotect for the
124  * copy_page_range operation and flush_tlb_range is related to
125  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
126  * ptep_get_and_clear do not flush the TLBs directly if the mm has
127  * only one user. At the end of the update the flush_tlb_mm and
128  * flush_tlb_range functions need to do the flush.
129  */
130 #define flush_tlb()				do { } while (0)
131 #define flush_tlb_all()				do { } while (0)
132 #define flush_tlb_page(vma, addr)		do { } while (0)
133 
134 static inline void flush_tlb_mm(struct mm_struct *mm)
135 {
136 	__tlb_flush_mm_lazy(mm);
137 }
138 
139 static inline void flush_tlb_range(struct vm_area_struct *vma,
140 				   unsigned long start, unsigned long end)
141 {
142 	__tlb_flush_mm_lazy(vma->vm_mm);
143 }
144 
145 static inline void flush_tlb_kernel_range(unsigned long start,
146 					  unsigned long end)
147 {
148 	__tlb_flush_kernel();
149 }
150 
151 #endif /* _S390_TLBFLUSH_H */
152