xref: /openbmc/linux/arch/s390/include/asm/tlbflush.h (revision 615c36f5)
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 __s390x__
31 	if (!MACHINE_HAS_CSP) {
32 		smp_ptlb_all();
33 		return;
34 	}
35 #endif /* __s390x__ */
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 	if (unlikely(cpumask_empty(mm_cpumask(mm))))
78 		return;
79 	/*
80 	 * If the machine has IDTE we prefer to do a per mm flush
81 	 * on all cpus instead of doing a local flush if the mm
82 	 * only ran on the local cpu.
83 	 */
84 	if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list))
85 		__tlb_flush_idte((unsigned long) mm->pgd |
86 				 mm->context.asce_bits);
87 	else
88 		__tlb_flush_full(mm);
89 }
90 
91 static inline void __tlb_flush_mm_cond(struct mm_struct * mm)
92 {
93 	spin_lock(&mm->page_table_lock);
94 	if (mm->context.flush_mm) {
95 		__tlb_flush_mm(mm);
96 		mm->context.flush_mm = 0;
97 	}
98 	spin_unlock(&mm->page_table_lock);
99 }
100 
101 /*
102  * TLB flushing:
103  *  flush_tlb() - flushes the current mm struct TLBs
104  *  flush_tlb_all() - flushes all processes TLBs
105  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
106  *  flush_tlb_page(vma, vmaddr) - flushes one page
107  *  flush_tlb_range(vma, start, end) - flushes a range of pages
108  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
109  */
110 
111 /*
112  * flush_tlb_mm goes together with ptep_set_wrprotect for the
113  * copy_page_range operation and flush_tlb_range is related to
114  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
115  * ptep_get_and_clear do not flush the TLBs directly if the mm has
116  * only one user. At the end of the update the flush_tlb_mm and
117  * flush_tlb_range functions need to do the flush.
118  */
119 #define flush_tlb()				do { } while (0)
120 #define flush_tlb_all()				do { } while (0)
121 #define flush_tlb_page(vma, addr)		do { } while (0)
122 
123 static inline void flush_tlb_mm(struct mm_struct *mm)
124 {
125 	__tlb_flush_mm_cond(mm);
126 }
127 
128 static inline void flush_tlb_range(struct vm_area_struct *vma,
129 				   unsigned long start, unsigned long end)
130 {
131 	__tlb_flush_mm_cond(vma->vm_mm);
132 }
133 
134 static inline void flush_tlb_kernel_range(unsigned long start,
135 					  unsigned long end)
136 {
137 	__tlb_flush_mm(&init_mm);
138 }
139 
140 #endif /* _S390_TLBFLUSH_H */
141