fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / include / asm-sparc64 / mmu_context.h
blob9fc225ed5500d20c5372653389d8783ffc49ef4b
1 /* $Id: mmu_context.h,v 1.54 2002/02/09 19:49:31 davem Exp $ */
2 #ifndef __SPARC64_MMU_CONTEXT_H
3 #define __SPARC64_MMU_CONTEXT_H
5 /* Derived heavily from Linus's Alpha/AXP ASN code... */
7 #ifndef __ASSEMBLY__
9 #include <linux/spinlock.h>
10 #include <asm/system.h>
11 #include <asm/spitfire.h>
12 #include <asm-generic/mm_hooks.h>
14 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
18 extern spinlock_t ctx_alloc_lock;
19 extern unsigned long tlb_context_cache;
20 extern unsigned long mmu_context_bmap[];
22 extern void get_new_mmu_context(struct mm_struct *mm);
23 #ifdef CONFIG_SMP
24 extern void smp_new_mmu_context_version(void);
25 #else
26 #define smp_new_mmu_context_version() do { } while (0)
27 #endif
29 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
30 extern void destroy_context(struct mm_struct *mm);
32 extern void __tsb_context_switch(unsigned long pgd_pa,
33 struct tsb_config *tsb_base,
34 struct tsb_config *tsb_huge,
35 unsigned long tsb_descr_pa);
37 static inline void tsb_context_switch(struct mm_struct *mm)
39 __tsb_context_switch(__pa(mm->pgd),
40 &mm->context.tsb_block[0],
41 #ifdef CONFIG_HUGETLB_PAGE
42 (mm->context.tsb_block[1].tsb ?
43 &mm->context.tsb_block[1] :
44 NULL)
45 #else
46 NULL
47 #endif
48 , __pa(&mm->context.tsb_descr[0]));
51 extern void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long mm_rss);
52 #ifdef CONFIG_SMP
53 extern void smp_tsb_sync(struct mm_struct *mm);
54 #else
55 #define smp_tsb_sync(__mm) do { } while (0)
56 #endif
58 /* Set MMU context in the actual hardware. */
59 #define load_secondary_context(__mm) \
60 __asm__ __volatile__( \
61 "\n661: stxa %0, [%1] %2\n" \
62 " .section .sun4v_1insn_patch, \"ax\"\n" \
63 " .word 661b\n" \
64 " stxa %0, [%1] %3\n" \
65 " .previous\n" \
66 " flush %%g6\n" \
67 : /* No outputs */ \
68 : "r" (CTX_HWBITS((__mm)->context)), \
69 "r" (SECONDARY_CONTEXT), "i" (ASI_DMMU), "i" (ASI_MMU))
71 extern void __flush_tlb_mm(unsigned long, unsigned long);
73 /* Switch the current MM context. Interrupts are disabled. */
74 static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
76 unsigned long ctx_valid, flags;
77 int cpu;
79 if (unlikely(mm == &init_mm))
80 return;
82 spin_lock_irqsave(&mm->context.lock, flags);
83 ctx_valid = CTX_VALID(mm->context);
84 if (!ctx_valid)
85 get_new_mmu_context(mm);
87 /* We have to be extremely careful here or else we will miss
88 * a TSB grow if we switch back and forth between a kernel
89 * thread and an address space which has it's TSB size increased
90 * on another processor.
92 * It is possible to play some games in order to optimize the
93 * switch, but the safest thing to do is to unconditionally
94 * perform the secondary context load and the TSB context switch.
96 * For reference the bad case is, for address space "A":
98 * CPU 0 CPU 1
99 * run address space A
100 * set cpu0's bits in cpu_vm_mask
101 * switch to kernel thread, borrow
102 * address space A via entry_lazy_tlb
103 * run address space A
104 * set cpu1's bit in cpu_vm_mask
105 * flush_tlb_pending()
106 * reset cpu_vm_mask to just cpu1
107 * TSB grow
108 * run address space A
109 * context was valid, so skip
110 * TSB context switch
112 * At that point cpu0 continues to use a stale TSB, the one from
113 * before the TSB grow performed on cpu1. cpu1 did not cross-call
114 * cpu0 to update it's TSB because at that point the cpu_vm_mask
115 * only had cpu1 set in it.
117 load_secondary_context(mm);
118 tsb_context_switch(mm);
120 /* Any time a processor runs a context on an address space
121 * for the first time, we must flush that context out of the
122 * local TLB.
124 cpu = smp_processor_id();
125 if (!ctx_valid || !cpu_isset(cpu, mm->cpu_vm_mask)) {
126 cpu_set(cpu, mm->cpu_vm_mask);
127 __flush_tlb_mm(CTX_HWBITS(mm->context),
128 SECONDARY_CONTEXT);
130 spin_unlock_irqrestore(&mm->context.lock, flags);
133 #define deactivate_mm(tsk,mm) do { } while (0)
135 /* Activate a new MM instance for the current task. */
136 static inline void activate_mm(struct mm_struct *active_mm, struct mm_struct *mm)
138 unsigned long flags;
139 int cpu;
141 spin_lock_irqsave(&mm->context.lock, flags);
142 if (!CTX_VALID(mm->context))
143 get_new_mmu_context(mm);
144 cpu = smp_processor_id();
145 if (!cpu_isset(cpu, mm->cpu_vm_mask))
146 cpu_set(cpu, mm->cpu_vm_mask);
148 load_secondary_context(mm);
149 __flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT);
150 tsb_context_switch(mm);
151 spin_unlock_irqrestore(&mm->context.lock, flags);
154 #endif /* !(__ASSEMBLY__) */
156 #endif /* !(__SPARC64_MMU_CONTEXT_H) */