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 bool mm_iommu_preregistered(struct mm_struct *mm);
25 extern long mm_iommu_new(struct mm_struct *mm,
26 		unsigned long ua, unsigned long entries,
27 		struct mm_iommu_table_group_mem_t **pmem);
28 extern long mm_iommu_newdev(struct mm_struct *mm, unsigned long ua,
29 		unsigned long entries, unsigned long dev_hpa,
30 		struct mm_iommu_table_group_mem_t **pmem);
31 extern long mm_iommu_put(struct mm_struct *mm,
32 		struct mm_iommu_table_group_mem_t *mem);
33 extern void mm_iommu_init(struct mm_struct *mm);
34 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
35 		unsigned long ua, unsigned long size);
36 extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm,
37 		unsigned long ua, unsigned long entries);
38 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
39 		unsigned long ua, unsigned int pageshift, unsigned long *hpa);
40 extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
41 		unsigned int pageshift, unsigned long *size);
42 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
43 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
44 #else
45 static inline bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
46 		unsigned int pageshift, unsigned long *size)
47 {
48 	return false;
49 }
50 static inline void mm_iommu_init(struct mm_struct *mm) { }
51 #endif
52 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
53 
54 #ifdef CONFIG_PPC_BOOK3S_64
55 extern void radix__switch_mmu_context(struct mm_struct *prev,
56 				      struct mm_struct *next);
57 static inline void switch_mmu_context(struct mm_struct *prev,
58 				      struct mm_struct *next,
59 				      struct task_struct *tsk)
60 {
61 	if (radix_enabled())
62 		return radix__switch_mmu_context(prev, next);
63 	return switch_slb(tsk, next);
64 }
65 
66 extern int hash__alloc_context_id(void);
67 void __init hash__reserve_context_id(int id);
68 extern void __destroy_context(int context_id);
69 static inline void mmu_context_init(void) { }
70 
71 #ifdef CONFIG_PPC_64S_HASH_MMU
72 static inline int alloc_extended_context(struct mm_struct *mm,
73 					 unsigned long ea)
74 {
75 	int context_id;
76 
77 	int index = ea >> MAX_EA_BITS_PER_CONTEXT;
78 
79 	context_id = hash__alloc_context_id();
80 	if (context_id < 0)
81 		return context_id;
82 
83 	VM_WARN_ON(mm->context.extended_id[index]);
84 	mm->context.extended_id[index] = context_id;
85 	return context_id;
86 }
87 
88 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
89 {
90 	int context_id;
91 
92 	context_id = get_user_context(&mm->context, ea);
93 	if (!context_id)
94 		return true;
95 	return false;
96 }
97 #endif
98 
99 #else
100 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
101 			       struct task_struct *tsk);
102 extern unsigned long __init_new_context(void);
103 extern void __destroy_context(unsigned long context_id);
104 extern void mmu_context_init(void);
105 static inline int alloc_extended_context(struct mm_struct *mm,
106 					 unsigned long ea)
107 {
108 	/* non book3s_64 should never find this called */
109 	WARN_ON(1);
110 	return -ENOMEM;
111 }
112 
113 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
114 {
115 	return false;
116 }
117 #endif
118 
119 extern int use_cop(unsigned long acop, struct mm_struct *mm);
120 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
121 
122 #ifdef CONFIG_PPC_BOOK3S_64
123 static inline void inc_mm_active_cpus(struct mm_struct *mm)
124 {
125 	atomic_inc(&mm->context.active_cpus);
126 }
127 
128 static inline void dec_mm_active_cpus(struct mm_struct *mm)
129 {
130 	atomic_dec(&mm->context.active_cpus);
131 }
132 
133 static inline void mm_context_add_copro(struct mm_struct *mm)
134 {
135 	/*
136 	 * If any copro is in use, increment the active CPU count
137 	 * in order to force TLB invalidations to be global as to
138 	 * propagate to the Nest MMU.
139 	 */
140 	if (atomic_inc_return(&mm->context.copros) == 1)
141 		inc_mm_active_cpus(mm);
142 }
143 
144 static inline void mm_context_remove_copro(struct mm_struct *mm)
145 {
146 	int c;
147 
148 	/*
149 	 * When removing the last copro, we need to broadcast a global
150 	 * flush of the full mm, as the next TLBI may be local and the
151 	 * nMMU and/or PSL need to be cleaned up.
152 	 *
153 	 * Both the 'copros' and 'active_cpus' counts are looked at in
154 	 * flush_all_mm() to determine the scope (local/global) of the
155 	 * TLBIs, so we need to flush first before decrementing
156 	 * 'copros'. If this API is used by several callers for the
157 	 * same context, it can lead to over-flushing. It's hopefully
158 	 * not common enough to be a problem.
159 	 *
160 	 * Skip on hash, as we don't know how to do the proper flush
161 	 * for the time being. Invalidations will remain global if
162 	 * used on hash. Note that we can't drop 'copros' either, as
163 	 * it could make some invalidations local with no flush
164 	 * in-between.
165 	 */
166 	if (radix_enabled()) {
167 		flush_all_mm(mm);
168 
169 		c = atomic_dec_if_positive(&mm->context.copros);
170 		/* Detect imbalance between add and remove */
171 		WARN_ON(c < 0);
172 
173 		if (c == 0)
174 			dec_mm_active_cpus(mm);
175 	}
176 }
177 
178 /*
179  * vas_windows counter shows number of open windows in the mm
180  * context. During context switch, use this counter to clear the
181  * foreign real address mapping (CP_ABORT) for the thread / process
182  * that intend to use COPY/PASTE. When a process closes all windows,
183  * disable CP_ABORT which is expensive to run.
184  *
185  * For user context, register a copro so that TLBIs are seen by the
186  * nest MMU. mm_context_add/remove_vas_window() are used only for user
187  * space windows.
188  */
189 static inline void mm_context_add_vas_window(struct mm_struct *mm)
190 {
191 	atomic_inc(&mm->context.vas_windows);
192 	mm_context_add_copro(mm);
193 }
194 
195 static inline void mm_context_remove_vas_window(struct mm_struct *mm)
196 {
197 	int v;
198 
199 	mm_context_remove_copro(mm);
200 	v = atomic_dec_if_positive(&mm->context.vas_windows);
201 
202 	/* Detect imbalance between add and remove */
203 	WARN_ON(v < 0);
204 }
205 #else
206 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
207 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
208 static inline void mm_context_add_copro(struct mm_struct *mm) { }
209 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
210 #endif
211 
212 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
213 void do_h_rpt_invalidate_prt(unsigned long pid, unsigned long lpid,
214 			     unsigned long type, unsigned long pg_sizes,
215 			     unsigned long start, unsigned long end);
216 #else
217 static inline void do_h_rpt_invalidate_prt(unsigned long pid,
218 					   unsigned long lpid,
219 					   unsigned long type,
220 					   unsigned long pg_sizes,
221 					   unsigned long start,
222 					   unsigned long end) { }
223 #endif
224 
225 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
226 			       struct task_struct *tsk);
227 
228 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
229 			     struct task_struct *tsk)
230 {
231 	unsigned long flags;
232 
233 	local_irq_save(flags);
234 	switch_mm_irqs_off(prev, next, tsk);
235 	local_irq_restore(flags);
236 }
237 #define switch_mm_irqs_off switch_mm_irqs_off
238 
239 /*
240  * After we have set current->mm to a new value, this activates
241  * the context for the new mm so we see the new mappings.
242  */
243 #define activate_mm activate_mm
244 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
245 {
246 	switch_mm_irqs_off(prev, next, current);
247 }
248 
249 /* We don't currently use enter_lazy_tlb() for anything */
250 #ifdef CONFIG_PPC_BOOK3E_64
251 #define enter_lazy_tlb enter_lazy_tlb
252 static inline void enter_lazy_tlb(struct mm_struct *mm,
253 				  struct task_struct *tsk)
254 {
255 	/* 64-bit Book3E keeps track of current PGD in the PACA */
256 	get_paca()->pgd = NULL;
257 }
258 #endif
259 
260 extern void arch_exit_mmap(struct mm_struct *mm);
261 
262 static inline void arch_unmap(struct mm_struct *mm,
263 			      unsigned long start, unsigned long end)
264 {
265 	unsigned long vdso_base = (unsigned long)mm->context.vdso;
266 
267 	if (start <= vdso_base && vdso_base < end)
268 		mm->context.vdso = NULL;
269 }
270 
271 #ifdef CONFIG_PPC_MEM_KEYS
272 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
273 			       bool execute, bool foreign);
274 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
275 #else /* CONFIG_PPC_MEM_KEYS */
276 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
277 		bool write, bool execute, bool foreign)
278 {
279 	/* by default, allow everything */
280 	return true;
281 }
282 
283 #define pkey_mm_init(mm)
284 #define arch_dup_pkeys(oldmm, mm)
285 
286 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
287 {
288 	return 0x0UL;
289 }
290 
291 #endif /* CONFIG_PPC_MEM_KEYS */
292 
293 static inline int arch_dup_mmap(struct mm_struct *oldmm,
294 				struct mm_struct *mm)
295 {
296 	arch_dup_pkeys(oldmm, mm);
297 	return 0;
298 }
299 
300 #include <asm-generic/mmu_context.h>
301 
302 #endif /* __KERNEL__ */
303 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
304