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 void mm_iommu_cleanup(struct mm_struct *mm);
35 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
36 		unsigned long ua, unsigned long size);
37 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
38 		struct mm_struct *mm, unsigned long ua, unsigned long size);
39 extern struct mm_iommu_table_group_mem_t *mm_iommu_get(struct mm_struct *mm,
40 		unsigned long ua, unsigned long entries);
41 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
42 		unsigned long ua, unsigned int pageshift, unsigned long *hpa);
43 extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
44 		unsigned long ua, unsigned int pageshift, unsigned long *hpa);
45 extern void mm_iommu_ua_mark_dirty_rm(struct mm_struct *mm, unsigned long ua);
46 extern bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
47 		unsigned int pageshift, unsigned long *size);
48 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
49 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
50 #else
51 static inline bool mm_iommu_is_devmem(struct mm_struct *mm, unsigned long hpa,
52 		unsigned int pageshift, unsigned long *size)
53 {
54 	return false;
55 }
56 static inline void mm_iommu_init(struct mm_struct *mm) { }
57 #endif
58 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
59 
60 #ifdef CONFIG_PPC_BOOK3S_64
61 extern void radix__switch_mmu_context(struct mm_struct *prev,
62 				      struct mm_struct *next);
63 static inline void switch_mmu_context(struct mm_struct *prev,
64 				      struct mm_struct *next,
65 				      struct task_struct *tsk)
66 {
67 	if (radix_enabled())
68 		return radix__switch_mmu_context(prev, next);
69 	return switch_slb(tsk, next);
70 }
71 
72 extern int hash__alloc_context_id(void);
73 void __init hash__reserve_context_id(int id);
74 extern void __destroy_context(int context_id);
75 static inline void mmu_context_init(void) { }
76 
77 #ifdef CONFIG_PPC_64S_HASH_MMU
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 #endif
104 
105 #else
106 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
107 			       struct task_struct *tsk);
108 extern unsigned long __init_new_context(void);
109 extern void __destroy_context(unsigned long context_id);
110 extern void mmu_context_init(void);
111 static 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 
119 static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
120 {
121 	return false;
122 }
123 #endif
124 
125 extern void switch_cop(struct mm_struct *next);
126 extern int use_cop(unsigned long acop, struct mm_struct *mm);
127 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
128 
129 #ifdef CONFIG_PPC_BOOK3S_64
130 static inline void inc_mm_active_cpus(struct mm_struct *mm)
131 {
132 	atomic_inc(&mm->context.active_cpus);
133 }
134 
135 static inline void dec_mm_active_cpus(struct mm_struct *mm)
136 {
137 	atomic_dec(&mm->context.active_cpus);
138 }
139 
140 static inline void mm_context_add_copro(struct mm_struct *mm)
141 {
142 	/*
143 	 * If any copro is in use, increment the active CPU count
144 	 * in order to force TLB invalidations to be global as to
145 	 * propagate to the Nest MMU.
146 	 */
147 	if (atomic_inc_return(&mm->context.copros) == 1)
148 		inc_mm_active_cpus(mm);
149 }
150 
151 static inline void mm_context_remove_copro(struct mm_struct *mm)
152 {
153 	int c;
154 
155 	/*
156 	 * When removing the last copro, we need to broadcast a global
157 	 * flush of the full mm, as the next TLBI may be local and the
158 	 * nMMU and/or PSL need to be cleaned up.
159 	 *
160 	 * Both the 'copros' and 'active_cpus' counts are looked at in
161 	 * flush_all_mm() to determine the scope (local/global) of the
162 	 * TLBIs, so we need to flush first before decrementing
163 	 * 'copros'. If this API is used by several callers for the
164 	 * same context, it can lead to over-flushing. It's hopefully
165 	 * not common enough to be a problem.
166 	 *
167 	 * Skip on hash, as we don't know how to do the proper flush
168 	 * for the time being. Invalidations will remain global if
169 	 * used on hash. Note that we can't drop 'copros' either, as
170 	 * it could make some invalidations local with no flush
171 	 * in-between.
172 	 */
173 	if (radix_enabled()) {
174 		flush_all_mm(mm);
175 
176 		c = atomic_dec_if_positive(&mm->context.copros);
177 		/* Detect imbalance between add and remove */
178 		WARN_ON(c < 0);
179 
180 		if (c == 0)
181 			dec_mm_active_cpus(mm);
182 	}
183 }
184 
185 /*
186  * vas_windows counter shows number of open windows in the mm
187  * context. During context switch, use this counter to clear the
188  * foreign real address mapping (CP_ABORT) for the thread / process
189  * that intend to use COPY/PASTE. When a process closes all windows,
190  * disable CP_ABORT which is expensive to run.
191  *
192  * For user context, register a copro so that TLBIs are seen by the
193  * nest MMU. mm_context_add/remove_vas_window() are used only for user
194  * space windows.
195  */
196 static inline void mm_context_add_vas_window(struct mm_struct *mm)
197 {
198 	atomic_inc(&mm->context.vas_windows);
199 	mm_context_add_copro(mm);
200 }
201 
202 static inline void mm_context_remove_vas_window(struct mm_struct *mm)
203 {
204 	int v;
205 
206 	mm_context_remove_copro(mm);
207 	v = atomic_dec_if_positive(&mm->context.vas_windows);
208 
209 	/* Detect imbalance between add and remove */
210 	WARN_ON(v < 0);
211 }
212 #else
213 static inline void inc_mm_active_cpus(struct mm_struct *mm) { }
214 static inline void dec_mm_active_cpus(struct mm_struct *mm) { }
215 static inline void mm_context_add_copro(struct mm_struct *mm) { }
216 static inline void mm_context_remove_copro(struct mm_struct *mm) { }
217 #endif
218 
219 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
220 void do_h_rpt_invalidate_prt(unsigned long pid, unsigned long lpid,
221 			     unsigned long type, unsigned long pg_sizes,
222 			     unsigned long start, unsigned long end);
223 #else
224 static inline void do_h_rpt_invalidate_prt(unsigned long pid,
225 					   unsigned long lpid,
226 					   unsigned long type,
227 					   unsigned long pg_sizes,
228 					   unsigned long start,
229 					   unsigned long end) { }
230 #endif
231 
232 extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
233 			       struct task_struct *tsk);
234 
235 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
236 			     struct task_struct *tsk)
237 {
238 	unsigned long flags;
239 
240 	local_irq_save(flags);
241 	switch_mm_irqs_off(prev, next, tsk);
242 	local_irq_restore(flags);
243 }
244 #define switch_mm_irqs_off switch_mm_irqs_off
245 
246 /*
247  * After we have set current->mm to a new value, this activates
248  * the context for the new mm so we see the new mappings.
249  */
250 #define activate_mm activate_mm
251 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
252 {
253 	switch_mm_irqs_off(prev, next, current);
254 }
255 
256 /* We don't currently use enter_lazy_tlb() for anything */
257 #ifdef CONFIG_PPC_BOOK3E_64
258 #define enter_lazy_tlb enter_lazy_tlb
259 static inline void enter_lazy_tlb(struct mm_struct *mm,
260 				  struct task_struct *tsk)
261 {
262 	/* 64-bit Book3E keeps track of current PGD in the PACA */
263 	get_paca()->pgd = NULL;
264 }
265 #endif
266 
267 extern void arch_exit_mmap(struct mm_struct *mm);
268 
269 static inline void arch_unmap(struct mm_struct *mm,
270 			      unsigned long start, unsigned long end)
271 {
272 	unsigned long vdso_base = (unsigned long)mm->context.vdso;
273 
274 	if (start <= vdso_base && vdso_base < end)
275 		mm->context.vdso = NULL;
276 }
277 
278 #ifdef CONFIG_PPC_MEM_KEYS
279 bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
280 			       bool execute, bool foreign);
281 void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm);
282 #else /* CONFIG_PPC_MEM_KEYS */
283 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
284 		bool write, bool execute, bool foreign)
285 {
286 	/* by default, allow everything */
287 	return true;
288 }
289 
290 #define pkey_mm_init(mm)
291 #define arch_dup_pkeys(oldmm, mm)
292 
293 static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
294 {
295 	return 0x0UL;
296 }
297 
298 #endif /* CONFIG_PPC_MEM_KEYS */
299 
300 static inline int arch_dup_mmap(struct mm_struct *oldmm,
301 				struct mm_struct *mm)
302 {
303 	arch_dup_pkeys(oldmm, mm);
304 	return 0;
305 }
306 
307 #include <asm-generic/mmu_context.h>
308 
309 #endif /* __KERNEL__ */
310 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
311