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
18 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
19 #define destroy_context destroy_context
20 extern void destroy_context(struct mm_struct *mm);
21 #ifdef CONFIG_SPAPR_TCE_IOMMU
22 struct mm_iommu_table_group_mem_t;
23 
24 extern int isolate_lru_page(struct page *page);	/* from internal.h */
25 extern bool mm_iommu_preregistered(struct mm_struct *mm);
26 extern long mm_iommu_new(struct mm_struct *mm,
27 		unsigned long ua, unsigned long entries,
28 		struct mm_iommu_table_group_mem_t **pmem);
29 extern 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);
32 extern long mm_iommu_put(struct mm_struct *mm,
33 		struct mm_iommu_table_group_mem_t *mem);
34 extern void mm_iommu_init(struct mm_struct *mm);
35 extern void mm_iommu_cleanup(struct mm_struct *mm);
36 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
37 		unsigned long ua, unsigned long size);
38 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
39 		struct mm_struct *mm, unsigned long ua, unsigned long size);
40 extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm,
41 		unsigned long ua, unsigned long entries);
42 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
43 		unsigned long ua, unsigned int pageshift, unsigned long *hpa);
44 extern 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);
46 extern void mm_iommu_ua_mark_dirty_rm(struct mm_struct *mm, unsigned long ua);
47 extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
48 		unsigned int pageshift, unsigned long *size);
49 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
50 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
51 #else
52 static 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 }
57 static inline void mm_iommu_init(struct mm_struct *mm) { }
58 #endif
59 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
60 
61 #ifdef CONFIG_PPC_BOOK3S_64
62 extern void radix__switch_mmu_context(struct mm_struct *prev,
63 				      struct mm_struct *next);
64 static inline void switch_mmu_context(struct mm_struct *prev,
65 				      struct mm_struct *next,
66 				      struct task_struct *tsk)
67 {
68 	if (radix_enabled())
69 		return radix__switch_mmu_context(prev, next);
70 	return switch_slb(tsk, next);
71 }
72 
73 extern int hash__alloc_context_id(void);
74 extern void hash__reserve_context_id(int id);
75 extern void __destroy_context(int context_id);
76 static inline void mmu_context_init(void) { }
77 
78 static inline int alloc_extended_context(struct mm_struct *mm,
79 					 unsigned long ea)
80 {
81 	int context_id;
82 
83 	int index = ea >> MAX_EA_BITS_PER_CONTEXT;
84 
85 	context_id = hash__alloc_context_id();
86 	if (context_id < 0)
87 		return context_id;
88 
89 	VM_WARN_ON(mm->context.extended_id[index]);
90 	mm->context.extended_id[index] = context_id;
91 	return context_id;
92 }
93 
94 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
95 {
96 	int context_id;
97 
98 	context_id = get_user_context(&mm->context, ea);
99 	if (!context_id)
100 		return true;
101 	return false;
102 }
103 
104 #else
105 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
106 			       struct task_struct *tsk);
107 extern unsigned long __init_new_context(void);
108 extern void __destroy_context(unsigned long context_id);
109 extern void mmu_context_init(void);
110 static inline int alloc_extended_context(struct mm_struct *mm,
111 					 unsigned long ea)
112 {
113 	/* non book3s_64 should never find this called */
114 	WARN_ON(1);
115 	return -ENOMEM;
116 }
117 
118 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
119 {
120 	return false;
121 }
122 #endif
123 
124 extern void switch_cop(struct mm_struct *next);
125 extern int use_cop(unsigned long acop, struct mm_struct *mm);
126 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
127 
128 #ifdef CONFIG_PPC_BOOK3S_64
129 static inline void inc_mm_active_cpus(struct mm_struct *mm)
130 {
131 	atomic_inc(&mm->context.active_cpus);
132 }
133 
134 static inline void dec_mm_active_cpus(struct mm_struct *mm)
135 {
136 	atomic_dec(&mm->context.active_cpus);
137 }
138 
139 static inline void mm_context_add_copro(struct mm_struct *mm)
140 {
141 	/*
142 	 * If any copro is in use, increment the active CPU count
143 	 * in order to force TLB invalidations to be global as to
144 	 * propagate to the Nest MMU.
145 	 */
146 	if (atomic_inc_return(&mm->context.copros) == 1)
147 		inc_mm_active_cpus(mm);
148 }
149 
150 static inline void mm_context_remove_copro(struct mm_struct *mm)
151 {
152 	int c;
153 
154 	/*
155 	 * When removing the last copro, we need to broadcast a global
156 	 * flush of the full mm, as the next TLBI may be local and the
157 	 * nMMU and/or PSL need to be cleaned up.
158 	 *
159 	 * Both the 'copros' and 'active_cpus' counts are looked at in
160 	 * flush_all_mm() to determine the scope (local/global) of the
161 	 * TLBIs, so we need to flush first before decrementing
162 	 * 'copros'. If this API is used by several callers for the
163 	 * same context, it can lead to over-flushing. It's hopefully
164 	 * not common enough to be a problem.
165 	 *
166 	 * Skip on hash, as we don't know how to do the proper flush
167 	 * for the time being. Invalidations will remain global if
168 	 * used on hash. Note that we can't drop 'copros' either, as
169 	 * it could make some invalidations local with no flush
170 	 * in-between.
171 	 */
172 	if (radix_enabled()) {
173 		flush_all_mm(mm);
174 
175 		c = atomic_dec_if_positive(&mm->context.copros);
176 		/* Detect imbalance between add and remove */
177 		WARN_ON(c < 0);
178 
179 		if (c == 0)
180 			dec_mm_active_cpus(mm);
181 	}
182 }
183 
184 /*
185  * vas_windows counter shows number of open windows in the mm
186  * context. During context switch, use this counter to clear the
187  * foreign real address mapping (CP_ABORT) for the thread / process
188  * that intend to use COPY/PASTE. When a process closes all windows,
189  * disable CP_ABORT which is expensive to run.
190  *
191  * For user context, register a copro so that TLBIs are seen by the
192  * nest MMU. mm_context_add/remove_vas_window() are used only for user
193  * space windows.
194  */
195 static inline void mm_context_add_vas_window(struct mm_struct *mm)
196 {
197 	atomic_inc(&mm->context.vas_windows);
198 	mm_context_add_copro(mm);
199 }
200 
201 static inline void mm_context_remove_vas_window(struct mm_struct *mm)
202 {
203 	int v;
204 
205 	mm_context_remove_copro(mm);
206 	v = atomic_dec_if_positive(&mm->context.vas_windows);
207 
208 	/* Detect imbalance between add and remove */
209 	WARN_ON(v < 0);
210 }
211 #else
212 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
213 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
214 static inline void mm_context_add_copro(struct mm_struct *mm) { }
215 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
216 #endif
217 
218 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
219 void do_h_rpt_invalidate_prt(unsigned long pid, unsigned long lpid,
220 			     unsigned long type, unsigned long pg_sizes,
221 			     unsigned long start, unsigned long end);
222 #else
223 static inline void do_h_rpt_invalidate_prt(unsigned long pid,
224 					   unsigned long lpid,
225 					   unsigned long type,
226 					   unsigned long pg_sizes,
227 					   unsigned long start,
228 					   unsigned long end) { }
229 #endif
230 
231 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
232 			       struct task_struct *tsk);
233 
234 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
235 			     struct task_struct *tsk)
236 {
237 	unsigned long flags;
238 
239 	local_irq_save(flags);
240 	switch_mm_irqs_off(prev, next, tsk);
241 	local_irq_restore(flags);
242 }
243 #define switch_mm_irqs_off switch_mm_irqs_off
244 
245 /*
246  * After we have set current->mm to a new value, this activates
247  * the context for the new mm so we see the new mappings.
248  */
249 #define activate_mm activate_mm
250 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
251 {
252 	switch_mm_irqs_off(prev, next, current);
253 }
254 
255 /* We don't currently use enter_lazy_tlb() for anything */
256 #ifdef CONFIG_PPC_BOOK3E_64
257 #define enter_lazy_tlb enter_lazy_tlb
258 static inline void enter_lazy_tlb(struct mm_struct *mm,
259 				  struct task_struct *tsk)
260 {
261 	/* 64-bit Book3E keeps track of current PGD in the PACA */
262 	get_paca()->pgd = NULL;
263 }
264 #endif
265 
266 extern void arch_exit_mmap(struct mm_struct *mm);
267 
268 static inline void arch_unmap(struct mm_struct *mm,
269 			      unsigned long start, unsigned long end)
270 {
271 	unsigned long vdso_base = (unsigned long)mm->context.vdso;
272 
273 	if (start <= vdso_base && vdso_base < end)
274 		mm->context.vdso = NULL;
275 }
276 
277 #ifdef CONFIG_PPC_MEM_KEYS
278 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
279 			       bool execute, bool foreign);
280 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
281 #else /* CONFIG_PPC_MEM_KEYS */
282 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
283 		bool write, bool execute, bool foreign)
284 {
285 	/* by default, allow everything */
286 	return true;
287 }
288 
289 #define pkey_mm_init(mm)
290 #define arch_dup_pkeys(oldmm, mm)
291 
292 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
293 {
294 	return 0x0UL;
295 }
296 
297 #endif /* CONFIG_PPC_MEM_KEYS */
298 
299 static inline int arch_dup_mmap(struct mm_struct *oldmm,
300 				struct mm_struct *mm)
301 {
302 	arch_dup_pkeys(oldmm, mm);
303 	return 0;
304 }
305 
306 #include <asm-generic/mmu_context.h>
307 
308 #endif /* __KERNEL__ */
309 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
310