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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_POWERPC_MMU_CONTEXT_H
3#define __ASM_POWERPC_MMU_CONTEXT_H
4#ifdef __KERNEL__
5
6#include <linux/kernel.h>
7#include <linux/mm.h>
8#include <linux/sched.h>
9#include <linux/spinlock.h>
10#include <asm/mmu.h>
11#include <asm/cputable.h>
12#include <asm/cputhreads.h>
13
14/*
15 * Most if the context management is out of line
16 */
17#define init_new_context init_new_context
18extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
19#define destroy_context destroy_context
20extern void destroy_context(struct mm_struct *mm);
21#ifdef CONFIG_SPAPR_TCE_IOMMU
22struct mm_iommu_table_group_mem_t;
23
24extern int isolate_lru_page(struct page *page); /* from internal.h */
25extern bool mm_iommu_preregistered(struct mm_struct *mm);
26extern long mm_iommu_new(struct mm_struct *mm,
27 unsigned long ua, unsigned long entries,
28 struct mm_iommu_table_group_mem_t **pmem);
29extern long mm_iommu_newdev(struct mm_struct *mm, unsigned long ua,
30 unsigned long entries, unsigned long dev_hpa,
31 struct mm_iommu_table_group_mem_t **pmem);
32extern long mm_iommu_put(struct mm_struct *mm,
33 struct mm_iommu_table_group_mem_t *mem);
34extern void mm_iommu_init(struct mm_struct *mm);
35extern void mm_iommu_cleanup(struct mm_struct *mm);
36extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
37 unsigned long ua, unsigned long size);
38extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
39 struct mm_struct *mm, unsigned long ua, unsigned long size);
40extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm,
41 unsigned long ua, unsigned long entries);
42extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
43 unsigned long ua, unsigned int pageshift, unsigned long *hpa);
44extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
45 unsigned long ua, unsigned int pageshift, unsigned long *hpa);
46extern void mm_iommu_ua_mark_dirty_rm(struct mm_struct *mm, unsigned long ua);
47extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
48 unsigned int pageshift, unsigned long *size);
49extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
50extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
51#else
52static inline bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
53 unsigned int pageshift, unsigned long *size)
54{
55 return false;
56}
57static inline void mm_iommu_init(struct mm_struct *mm) { }
58#endif
59extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
60extern void set_context(unsigned long id, pgd_t *pgd);
61
62#ifdef CONFIG_PPC_BOOK3S_64
63extern void radix__switch_mmu_context(struct mm_struct *prev,
64 struct mm_struct *next);
65static inline void switch_mmu_context(struct mm_struct *prev,
66 struct mm_struct *next,
67 struct task_struct *tsk)
68{
69 if (radix_enabled())
70 return radix__switch_mmu_context(prev, next);
71 return switch_slb(tsk, next);
72}
73
74extern int hash__alloc_context_id(void);
75extern void hash__reserve_context_id(int id);
76extern void __destroy_context(int context_id);
77static inline void mmu_context_init(void) { }
78
79static inline int alloc_extended_context(struct mm_struct *mm,
80 unsigned long ea)
81{
82 int context_id;
83
84 int index = ea >> MAX_EA_BITS_PER_CONTEXT;
85
86 context_id = hash__alloc_context_id();
87 if (context_id < 0)
88 return context_id;
89
90 VM_WARN_ON(mm->context.extended_id[index]);
91 mm->context.extended_id[index] = context_id;
92 return context_id;
93}
94
95static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
96{
97 int context_id;
98
99 context_id = get_user_context(&mm->context, ea);
100 if (!context_id)
101 return true;
102 return false;
103}
104
105#else
106extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
107 struct task_struct *tsk);
108extern unsigned long __init_new_context(void);
109extern void __destroy_context(unsigned long context_id);
110extern void mmu_context_init(void);
111static inline int alloc_extended_context(struct mm_struct *mm,
112 unsigned long ea)
113{
114 /* non book3s_64 should never find this called */
115 WARN_ON(1);
116 return -ENOMEM;
117}
118
119static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
120{
121 return false;
122}
123#endif
124
125#if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
126extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
127#else
128static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
129#endif
130
131extern void switch_cop(struct mm_struct *next);
132extern int use_cop(unsigned long acop, struct mm_struct *mm);
133extern void drop_cop(unsigned long acop, struct mm_struct *mm);
134
135#ifdef CONFIG_PPC_BOOK3S_64
136static inline void inc_mm_active_cpus(struct mm_struct *mm)
137{
138 atomic_inc(&mm->context.active_cpus);
139}
140
141static inline void dec_mm_active_cpus(struct mm_struct *mm)
142{
143 atomic_dec(&mm->context.active_cpus);
144}
145
146static inline void mm_context_add_copro(struct mm_struct *mm)
147{
148 /*
149 * If any copro is in use, increment the active CPU count
150 * in order to force TLB invalidations to be global as to
151 * propagate to the Nest MMU.
152 */
153 if (atomic_inc_return(&mm->context.copros) == 1)
154 inc_mm_active_cpus(mm);
155}
156
157static inline void mm_context_remove_copro(struct mm_struct *mm)
158{
159 int c;
160
161 /*
162 * When removing the last copro, we need to broadcast a global
163 * flush of the full mm, as the next TLBI may be local and the
164 * nMMU and/or PSL need to be cleaned up.
165 *
166 * Both the 'copros' and 'active_cpus' counts are looked at in
167 * flush_all_mm() to determine the scope (local/global) of the
168 * TLBIs, so we need to flush first before decrementing
169 * 'copros'. If this API is used by several callers for the
170 * same context, it can lead to over-flushing. It's hopefully
171 * not common enough to be a problem.
172 *
173 * Skip on hash, as we don't know how to do the proper flush
174 * for the time being. Invalidations will remain global if
175 * used on hash. Note that we can't drop 'copros' either, as
176 * it could make some invalidations local with no flush
177 * in-between.
178 */
179 if (radix_enabled()) {
180 flush_all_mm(mm);
181
182 c = atomic_dec_if_positive(&mm->context.copros);
183 /* Detect imbalance between add and remove */
184 WARN_ON(c < 0);
185
186 if (c == 0)
187 dec_mm_active_cpus(mm);
188 }
189}
190
191/*
192 * vas_windows counter shows number of open windows in the mm
193 * context. During context switch, use this counter to clear the
194 * foreign real address mapping (CP_ABORT) for the thread / process
195 * that intend to use COPY/PASTE. When a process closes all windows,
196 * disable CP_ABORT which is expensive to run.
197 *
198 * For user context, register a copro so that TLBIs are seen by the
199 * nest MMU. mm_context_add/remove_vas_window() are used only for user
200 * space windows.
201 */
202static inline void mm_context_add_vas_window(struct mm_struct *mm)
203{
204 atomic_inc(&mm->context.vas_windows);
205 mm_context_add_copro(mm);
206}
207
208static inline void mm_context_remove_vas_window(struct mm_struct *mm)
209{
210 int v;
211
212 mm_context_remove_copro(mm);
213 v = atomic_dec_if_positive(&mm->context.vas_windows);
214
215 /* Detect imbalance between add and remove */
216 WARN_ON(v < 0);
217}
218#else
219static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
220static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
221static inline void mm_context_add_copro(struct mm_struct *mm) { }
222static inline void mm_context_remove_copro(struct mm_struct *mm) { }
223#endif
224
225
226extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
227 struct task_struct *tsk);
228
229static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
230 struct task_struct *tsk)
231{
232 unsigned long flags;
233
234 local_irq_save(flags);
235 switch_mm_irqs_off(prev, next, tsk);
236 local_irq_restore(flags);
237}
238#define switch_mm_irqs_off switch_mm_irqs_off
239
240/*
241 * After we have set current->mm to a new value, this activates
242 * the context for the new mm so we see the new mappings.
243 */
244#define activate_mm activate_mm
245static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
246{
247 switch_mm_irqs_off(prev, next, current);
248}
249
250/* We don't currently use enter_lazy_tlb() for anything */
251#ifdef CONFIG_PPC_BOOK3E_64
252#define enter_lazy_tlb enter_lazy_tlb
253static inline void enter_lazy_tlb(struct mm_struct *mm,
254 struct task_struct *tsk)
255{
256 /* 64-bit Book3E keeps track of current PGD in the PACA */
257 get_paca()->pgd = NULL;
258}
259#endif
260
261extern void arch_exit_mmap(struct mm_struct *mm);
262
263static inline void arch_unmap(struct mm_struct *mm,
264 unsigned long start, unsigned long end)
265{
266 unsigned long vdso_base = (unsigned long)mm->context.vdso;
267
268 if (start <= vdso_base && vdso_base < end)
269 mm->context.vdso = NULL;
270}
271
272#ifdef CONFIG_PPC_MEM_KEYS
273bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
274 bool execute, bool foreign);
275void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
276#else /* CONFIG_PPC_MEM_KEYS */
277static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
278 bool write, bool execute, bool foreign)
279{
280 /* by default, allow everything */
281 return true;
282}
283
284#define pkey_mm_init(mm)
285#define arch_dup_pkeys(oldmm, mm)
286
287static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
288{
289 return 0x0UL;
290}
291
292#endif /* CONFIG_PPC_MEM_KEYS */
293
294static inline int arch_dup_mmap(struct mm_struct *oldmm,
295 struct mm_struct *mm)
296{
297 arch_dup_pkeys(oldmm, mm);
298 return 0;
299}
300
301#include <asm-generic/mmu_context.h>
302
303#endif /* __KERNEL__ */
304#endif /* __ASM_POWERPC_MMU_CONTEXT_H */