xref: /openbmc/linux/arch/s390/include/asm/tlbflush.h (revision 78700c0a)
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 /*
18  * Flush TLB entries for a specific ASCE on all CPUs
19  */
20 static inline void __tlb_flush_idte(unsigned long asce)
21 {
22 	/* Global TLB flush for the mm */
23 	asm volatile(
24 		"	.insn	rrf,0xb98e0000,0,%0,%1,0"
25 		: : "a" (2048), "a" (asce) : "cc");
26 }
27 
28 /*
29  * Flush TLB entries for a specific ASCE on the local CPU
30  */
31 static inline void __tlb_flush_idte_local(unsigned long asce)
32 {
33 	/* Local TLB flush for the mm */
34 	asm volatile(
35 		"	.insn	rrf,0xb98e0000,0,%0,%1,1"
36 		: : "a" (2048), "a" (asce) : "cc");
37 }
38 
39 #ifdef CONFIG_SMP
40 void smp_ptlb_all(void);
41 
42 /*
43  * Flush all TLB entries on all CPUs.
44  */
45 static inline void __tlb_flush_global(void)
46 {
47 	register unsigned long reg2 asm("2");
48 	register unsigned long reg3 asm("3");
49 	register unsigned long reg4 asm("4");
50 	long dummy;
51 
52 	dummy = 0;
53 	reg2 = reg3 = 0;
54 	reg4 = ((unsigned long) &dummy) + 1;
55 	asm volatile(
56 		"	csp	%0,%2"
57 		: : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
58 }
59 
60 /*
61  * Flush TLB entries for a specific mm on all CPUs (in case gmap is used
62  * this implicates multiple ASCEs!).
63  */
64 static inline void __tlb_flush_full(struct mm_struct *mm)
65 {
66 	preempt_disable();
67 	atomic_add(0x10000, &mm->context.attach_count);
68 	if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
69 		/* Local TLB flush */
70 		__tlb_flush_local();
71 	} else {
72 		/* Global TLB flush */
73 		__tlb_flush_global();
74 		/* Reset TLB flush mask */
75 		if (MACHINE_HAS_TLB_LC)
76 			cpumask_copy(mm_cpumask(mm),
77 				     &mm->context.cpu_attach_mask);
78 	}
79 	atomic_sub(0x10000, &mm->context.attach_count);
80 	preempt_enable();
81 }
82 
83 /*
84  * Flush TLB entries for a specific ASCE on all CPUs.
85  */
86 static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
87 {
88 	int active, count;
89 
90 	preempt_disable();
91 	active = (mm == current->active_mm) ? 1 : 0;
92 	count = atomic_add_return(0x10000, &mm->context.attach_count);
93 	if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
94 	    cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
95 		__tlb_flush_idte_local(asce);
96 	} else {
97 		if (MACHINE_HAS_IDTE)
98 			__tlb_flush_idte(asce);
99 		else
100 			__tlb_flush_global();
101 		/* Reset TLB flush mask */
102 		if (MACHINE_HAS_TLB_LC)
103 			cpumask_copy(mm_cpumask(mm),
104 				     &mm->context.cpu_attach_mask);
105 	}
106 	atomic_sub(0x10000, &mm->context.attach_count);
107 	preempt_enable();
108 }
109 
110 static inline void __tlb_flush_kernel(void)
111 {
112 	if (MACHINE_HAS_IDTE)
113 		__tlb_flush_idte(init_mm.context.asce);
114 	else
115 		__tlb_flush_global();
116 }
117 #else
118 #define __tlb_flush_global()	__tlb_flush_local()
119 #define __tlb_flush_full(mm)	__tlb_flush_local()
120 
121 /*
122  * Flush TLB entries for a specific ASCE on all CPUs.
123  */
124 static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
125 {
126 	if (MACHINE_HAS_TLB_LC)
127 		__tlb_flush_idte_local(asce);
128 	else
129 		__tlb_flush_local();
130 }
131 
132 static inline void __tlb_flush_kernel(void)
133 {
134 	if (MACHINE_HAS_TLB_LC)
135 		__tlb_flush_idte_local(init_mm.context.asce);
136 	else
137 		__tlb_flush_local();
138 }
139 #endif
140 
141 static inline void __tlb_flush_mm(struct mm_struct * mm)
142 {
143 	/*
144 	 * If the machine has IDTE we prefer to do a per mm flush
145 	 * on all cpus instead of doing a local flush if the mm
146 	 * only ran on the local cpu.
147 	 */
148 	if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list))
149 		__tlb_flush_asce(mm, mm->context.asce);
150 	else
151 		__tlb_flush_full(mm);
152 }
153 
154 static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
155 {
156 	if (mm->context.flush_mm) {
157 		__tlb_flush_mm(mm);
158 		mm->context.flush_mm = 0;
159 	}
160 }
161 
162 /*
163  * TLB flushing:
164  *  flush_tlb() - flushes the current mm struct TLBs
165  *  flush_tlb_all() - flushes all processes TLBs
166  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
167  *  flush_tlb_page(vma, vmaddr) - flushes one page
168  *  flush_tlb_range(vma, start, end) - flushes a range of pages
169  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
170  */
171 
172 /*
173  * flush_tlb_mm goes together with ptep_set_wrprotect for the
174  * copy_page_range operation and flush_tlb_range is related to
175  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
176  * ptep_get_and_clear do not flush the TLBs directly if the mm has
177  * only one user. At the end of the update the flush_tlb_mm and
178  * flush_tlb_range functions need to do the flush.
179  */
180 #define flush_tlb()				do { } while (0)
181 #define flush_tlb_all()				do { } while (0)
182 #define flush_tlb_page(vma, addr)		do { } while (0)
183 
184 static inline void flush_tlb_mm(struct mm_struct *mm)
185 {
186 	__tlb_flush_mm_lazy(mm);
187 }
188 
189 static inline void flush_tlb_range(struct vm_area_struct *vma,
190 				   unsigned long start, unsigned long end)
191 {
192 	__tlb_flush_mm_lazy(vma->vm_mm);
193 }
194 
195 static inline void flush_tlb_kernel_range(unsigned long start,
196 					  unsigned long end)
197 {
198 	__tlb_flush_kernel();
199 }
200 
201 #endif /* _S390_TLBFLUSH_H */
202