xref: /openbmc/linux/arch/s390/include/asm/tlbflush.h (revision b34081f1)
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 
9 /*
10  * Flush all tlb entries on the local cpu.
11  */
12 static inline void __tlb_flush_local(void)
13 {
14 	asm volatile("ptlb" : : : "memory");
15 }
16 
17 #ifdef CONFIG_SMP
18 /*
19  * Flush all tlb entries on all cpus.
20  */
21 void smp_ptlb_all(void);
22 
23 static inline void __tlb_flush_global(void)
24 {
25 	register unsigned long reg2 asm("2");
26 	register unsigned long reg3 asm("3");
27 	register unsigned long reg4 asm("4");
28 	long dummy;
29 
30 #ifndef CONFIG_64BIT
31 	if (!MACHINE_HAS_CSP) {
32 		smp_ptlb_all();
33 		return;
34 	}
35 #endif /* CONFIG_64BIT */
36 
37 	dummy = 0;
38 	reg2 = reg3 = 0;
39 	reg4 = ((unsigned long) &dummy) + 1;
40 	asm volatile(
41 		"	csp	%0,%2"
42 		: : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
43 }
44 
45 static inline void __tlb_flush_full(struct mm_struct *mm)
46 {
47 	cpumask_t local_cpumask;
48 
49 	preempt_disable();
50 	/*
51 	 * If the process only ran on the local cpu, do a local flush.
52 	 */
53 	cpumask_copy(&local_cpumask, cpumask_of(smp_processor_id()));
54 	if (cpumask_equal(mm_cpumask(mm), &local_cpumask))
55 		__tlb_flush_local();
56 	else
57 		__tlb_flush_global();
58 	preempt_enable();
59 }
60 #else
61 #define __tlb_flush_full(mm)	__tlb_flush_local()
62 #define __tlb_flush_global()	__tlb_flush_local()
63 #endif
64 
65 /*
66  * Flush all tlb entries of a page table on all cpus.
67  */
68 static inline void __tlb_flush_idte(unsigned long asce)
69 {
70 	asm volatile(
71 		"	.insn	rrf,0xb98e0000,0,%0,%1,0"
72 		: : "a" (2048), "a" (asce) : "cc" );
73 }
74 
75 static inline void __tlb_flush_mm(struct mm_struct * mm)
76 {
77 	/*
78 	 * If the machine has IDTE we prefer to do a per mm flush
79 	 * on all cpus instead of doing a local flush if the mm
80 	 * only ran on the local cpu.
81 	 */
82 	if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list))
83 		__tlb_flush_idte((unsigned long) mm->pgd |
84 				 mm->context.asce_bits);
85 	else
86 		__tlb_flush_full(mm);
87 }
88 
89 static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
90 {
91 	if (mm->context.flush_mm) {
92 		__tlb_flush_mm(mm);
93 		mm->context.flush_mm = 0;
94 	}
95 }
96 
97 /*
98  * TLB flushing:
99  *  flush_tlb() - flushes the current mm struct TLBs
100  *  flush_tlb_all() - flushes all processes TLBs
101  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
102  *  flush_tlb_page(vma, vmaddr) - flushes one page
103  *  flush_tlb_range(vma, start, end) - flushes a range of pages
104  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
105  */
106 
107 /*
108  * flush_tlb_mm goes together with ptep_set_wrprotect for the
109  * copy_page_range operation and flush_tlb_range is related to
110  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
111  * ptep_get_and_clear do not flush the TLBs directly if the mm has
112  * only one user. At the end of the update the flush_tlb_mm and
113  * flush_tlb_range functions need to do the flush.
114  */
115 #define flush_tlb()				do { } while (0)
116 #define flush_tlb_all()				do { } while (0)
117 #define flush_tlb_page(vma, addr)		do { } while (0)
118 
119 static inline void flush_tlb_mm(struct mm_struct *mm)
120 {
121 	__tlb_flush_mm_lazy(mm);
122 }
123 
124 static inline void flush_tlb_range(struct vm_area_struct *vma,
125 				   unsigned long start, unsigned long end)
126 {
127 	__tlb_flush_mm_lazy(vma->vm_mm);
128 }
129 
130 static inline void flush_tlb_kernel_range(unsigned long start,
131 					  unsigned long end)
132 {
133 	__tlb_flush_mm(&init_mm);
134 }
135 
136 #endif /* _S390_TLBFLUSH_H */
137