~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/xtensa/include/asm/mmu_context.h

Version: ~ [ linux-5.15-rc5 ] ~ [ linux-5.14.11 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.72 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.152 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.210 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.250 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.286 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.288 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Switch an MMU context.
  3  *
  4  * This file is subject to the terms and conditions of the GNU General Public
  5  * License.  See the file "COPYING" in the main directory of this archive
  6  * for more details.
  7  *
  8  * Copyright (C) 2001 - 2013 Tensilica Inc.
  9  */
 10 
 11 #ifndef _XTENSA_MMU_CONTEXT_H
 12 #define _XTENSA_MMU_CONTEXT_H
 13 
 14 #ifndef CONFIG_MMU
 15 #include <asm/nommu_context.h>
 16 #else
 17 
 18 #include <linux/stringify.h>
 19 #include <linux/sched.h>
 20 #include <linux/mm_types.h>
 21 #include <linux/pgtable.h>
 22 
 23 #include <asm/vectors.h>
 24 
 25 #include <asm/cacheflush.h>
 26 #include <asm/tlbflush.h>
 27 #include <asm-generic/mm_hooks.h>
 28 #include <asm-generic/percpu.h>
 29 
 30 #if (XCHAL_HAVE_TLBS != 1)
 31 # error "Linux must have an MMU!"
 32 #endif
 33 
 34 DECLARE_PER_CPU(unsigned long, asid_cache);
 35 #define cpu_asid_cache(cpu) per_cpu(asid_cache, cpu)
 36 
 37 /*
 38  * NO_CONTEXT is the invalid ASID value that we don't ever assign to
 39  * any user or kernel context.  We use the reserved values in the
 40  * ASID_INSERT macro below.
 41  *
 42  * 0 invalid
 43  * 1 kernel
 44  * 2 reserved
 45  * 3 reserved
 46  * 4...255 available
 47  */
 48 
 49 #define NO_CONTEXT      0
 50 #define ASID_USER_FIRST 4
 51 #define ASID_MASK       ((1 << XCHAL_MMU_ASID_BITS) - 1)
 52 #define ASID_INSERT(x)  (0x03020001 | (((x) & ASID_MASK) << 8))
 53 
 54 void init_mmu(void);
 55 void init_kio(void);
 56 
 57 static inline void set_rasid_register (unsigned long val)
 58 {
 59         __asm__ __volatile__ (" wsr %0, rasid\n\t"
 60                               " isync\n" : : "a" (val));
 61 }
 62 
 63 static inline unsigned long get_rasid_register (void)
 64 {
 65         unsigned long tmp;
 66         __asm__ __volatile__ (" rsr %0, rasid\n\t" : "=a" (tmp));
 67         return tmp;
 68 }
 69 
 70 static inline void get_new_mmu_context(struct mm_struct *mm, unsigned int cpu)
 71 {
 72         unsigned long asid = cpu_asid_cache(cpu);
 73         if ((++asid & ASID_MASK) == 0) {
 74                 /*
 75                  * Start new asid cycle; continue counting with next
 76                  * incarnation bits; skipping over 0, 1, 2, 3.
 77                  */
 78                 local_flush_tlb_all();
 79                 asid += ASID_USER_FIRST;
 80         }
 81         cpu_asid_cache(cpu) = asid;
 82         mm->context.asid[cpu] = asid;
 83         mm->context.cpu = cpu;
 84 }
 85 
 86 static inline void get_mmu_context(struct mm_struct *mm, unsigned int cpu)
 87 {
 88         /*
 89          * Check if our ASID is of an older version and thus invalid.
 90          */
 91 
 92         if (mm) {
 93                 unsigned long asid = mm->context.asid[cpu];
 94 
 95                 if (asid == NO_CONTEXT ||
 96                                 ((asid ^ cpu_asid_cache(cpu)) & ~ASID_MASK))
 97                         get_new_mmu_context(mm, cpu);
 98         }
 99 }
100 
101 static inline void activate_context(struct mm_struct *mm, unsigned int cpu)
102 {
103         get_mmu_context(mm, cpu);
104         set_rasid_register(ASID_INSERT(mm->context.asid[cpu]));
105         invalidate_page_directory();
106 }
107 
108 /*
109  * Initialize the context related info for a new mm_struct
110  * instance.  Valid cpu values are 0..(NR_CPUS-1), so initializing
111  * to -1 says the process has never run on any core.
112  */
113 
114 #define init_new_context init_new_context
115 static inline int init_new_context(struct task_struct *tsk,
116                 struct mm_struct *mm)
117 {
118         int cpu;
119         for_each_possible_cpu(cpu) {
120                 mm->context.asid[cpu] = NO_CONTEXT;
121         }
122         mm->context.cpu = -1;
123         return 0;
124 }
125 
126 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
127                              struct task_struct *tsk)
128 {
129         unsigned int cpu = smp_processor_id();
130         int migrated = next->context.cpu != cpu;
131         /* Flush the icache if we migrated to a new core. */
132         if (migrated) {
133                 __invalidate_icache_all();
134                 next->context.cpu = cpu;
135         }
136         if (migrated || prev != next)
137                 activate_context(next, cpu);
138 }
139 
140 /*
141  * Destroy context related info for an mm_struct that is about
142  * to be put to rest.
143  */
144 #define destroy_context destroy_context
145 static inline void destroy_context(struct mm_struct *mm)
146 {
147         invalidate_page_directory();
148 }
149 
150 
151 #include <asm-generic/mmu_context.h>
152 
153 #endif /* CONFIG_MMU */
154 #endif /* _XTENSA_MMU_CONTEXT_H */
155 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp