xref: /openbmc/linux/arch/s390/include/asm/tlbflush.h (revision afb46f79)
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 #ifndef CONFIG_64BIT
53 	if (!MACHINE_HAS_CSP) {
54 		smp_ptlb_all();
55 		return;
56 	}
57 #endif /* CONFIG_64BIT */
58 
59 	dummy = 0;
60 	reg2 = reg3 = 0;
61 	reg4 = ((unsigned long) &dummy) + 1;
62 	asm volatile(
63 		"	csp	%0,%2"
64 		: : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
65 }
66 
67 /*
68  * Flush TLB entries for a specific mm on all CPUs (in case gmap is used
69  * this implicates multiple ASCEs!).
70  */
71 static inline void __tlb_flush_full(struct mm_struct *mm)
72 {
73 	preempt_disable();
74 	atomic_add(0x10000, &mm->context.attach_count);
75 	if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
76 		/* Local TLB flush */
77 		__tlb_flush_local();
78 	} else {
79 		/* Global TLB flush */
80 		__tlb_flush_global();
81 		/* Reset TLB flush mask */
82 		if (MACHINE_HAS_TLB_LC)
83 			cpumask_copy(mm_cpumask(mm),
84 				     &mm->context.cpu_attach_mask);
85 	}
86 	atomic_sub(0x10000, &mm->context.attach_count);
87 	preempt_enable();
88 }
89 
90 /*
91  * Flush TLB entries for a specific ASCE on all CPUs.
92  */
93 static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
94 {
95 	int active, count;
96 
97 	preempt_disable();
98 	active = (mm == current->active_mm) ? 1 : 0;
99 	count = atomic_add_return(0x10000, &mm->context.attach_count);
100 	if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
101 	    cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
102 		__tlb_flush_idte_local(asce);
103 	} else {
104 		if (MACHINE_HAS_IDTE)
105 			__tlb_flush_idte(asce);
106 		else
107 			__tlb_flush_global();
108 		/* Reset TLB flush mask */
109 		if (MACHINE_HAS_TLB_LC)
110 			cpumask_copy(mm_cpumask(mm),
111 				     &mm->context.cpu_attach_mask);
112 	}
113 	atomic_sub(0x10000, &mm->context.attach_count);
114 	preempt_enable();
115 }
116 
117 static inline void __tlb_flush_kernel(void)
118 {
119 	if (MACHINE_HAS_IDTE)
120 		__tlb_flush_idte((unsigned long) init_mm.pgd |
121 				 init_mm.context.asce_bits);
122 	else
123 		__tlb_flush_global();
124 }
125 #else
126 #define __tlb_flush_global()	__tlb_flush_local()
127 #define __tlb_flush_full(mm)	__tlb_flush_local()
128 
129 /*
130  * Flush TLB entries for a specific ASCE on all CPUs.
131  */
132 static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
133 {
134 	if (MACHINE_HAS_TLB_LC)
135 		__tlb_flush_idte_local(asce);
136 	else
137 		__tlb_flush_local();
138 }
139 
140 static inline void __tlb_flush_kernel(void)
141 {
142 	if (MACHINE_HAS_TLB_LC)
143 		__tlb_flush_idte_local((unsigned long) init_mm.pgd |
144 				       init_mm.context.asce_bits);
145 	else
146 		__tlb_flush_local();
147 }
148 #endif
149 
150 static inline void __tlb_flush_mm(struct mm_struct * mm)
151 {
152 	/*
153 	 * If the machine has IDTE we prefer to do a per mm flush
154 	 * on all cpus instead of doing a local flush if the mm
155 	 * only ran on the local cpu.
156 	 */
157 	if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list))
158 		__tlb_flush_asce(mm, (unsigned long) mm->pgd |
159 				 mm->context.asce_bits);
160 	else
161 		__tlb_flush_full(mm);
162 }
163 
164 static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
165 {
166 	if (mm->context.flush_mm) {
167 		__tlb_flush_mm(mm);
168 		mm->context.flush_mm = 0;
169 	}
170 }
171 
172 /*
173  * TLB flushing:
174  *  flush_tlb() - flushes the current mm struct TLBs
175  *  flush_tlb_all() - flushes all processes TLBs
176  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
177  *  flush_tlb_page(vma, vmaddr) - flushes one page
178  *  flush_tlb_range(vma, start, end) - flushes a range of pages
179  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
180  */
181 
182 /*
183  * flush_tlb_mm goes together with ptep_set_wrprotect for the
184  * copy_page_range operation and flush_tlb_range is related to
185  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
186  * ptep_get_and_clear do not flush the TLBs directly if the mm has
187  * only one user. At the end of the update the flush_tlb_mm and
188  * flush_tlb_range functions need to do the flush.
189  */
190 #define flush_tlb()				do { } while (0)
191 #define flush_tlb_all()				do { } while (0)
192 #define flush_tlb_page(vma, addr)		do { } while (0)
193 
194 static inline void flush_tlb_mm(struct mm_struct *mm)
195 {
196 	__tlb_flush_mm_lazy(mm);
197 }
198 
199 static inline void flush_tlb_range(struct vm_area_struct *vma,
200 				   unsigned long start, unsigned long end)
201 {
202 	__tlb_flush_mm_lazy(vma->vm_mm);
203 }
204 
205 static inline void flush_tlb_kernel_range(unsigned long start,
206 					  unsigned long end)
207 {
208 	__tlb_flush_kernel();
209 }
210 
211 #endif /* _S390_TLBFLUSH_H */
212