LXR linux/arch/tile/include/asm/tlbflush.h

   1/*
   2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3 *
   4 *   This program is free software; you can redistribute it and/or
   5 *   modify it under the terms of the GNU General Public License
   6 *   as published by the Free Software Foundation, version 2.
   7 *
   8 *   This program is distributed in the hope that it will be useful, but
   9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11 *   NON INFRINGEMENT.  See the GNU General Public License for
  12 *   more details.
  13 */
  14
  15#ifndef _ASM_TILE_TLBFLUSH_H
  16#define _ASM_TILE_TLBFLUSH_H
  17
  18#include <linux/mm.h>
  19#include <linux/sched.h>
  20#include <linux/smp.h>
  21#include <asm/cacheflush.h>
  22#include <asm/page.h>
  23#include <hv/hypervisor.h>
  24
  25/*
  26 * Rather than associating each mm with its own ASID, we just use
  27 * ASIDs to allow us to lazily flush the TLB when we switch mms.
  28 * This way we only have to do an actual TLB flush on mm switch
  29 * every time we wrap ASIDs, not every single time we switch.
  30 *
  31 * FIXME: We might improve performance by keeping ASIDs around
  32 * properly, though since the hypervisor direct-maps VAs to TSB
  33 * entries, we're likely to have lost at least the executable page
  34 * mappings by the time we switch back to the original mm.
  35 */
  36DECLARE_PER_CPU(int, current_asid);
  37
  38/* The hypervisor tells us what ASIDs are available to us. */
  39extern int min_asid, max_asid;
  40
  41/* Pass as vma pointer for non-executable mapping, if no vma available. */
  42#define FLUSH_NONEXEC ((struct vm_area_struct *)-1UL)
  43
  44/* Flush a single user page on this cpu. */
  45static inline void local_flush_tlb_page(struct vm_area_struct *vma,
  46                                        unsigned long addr,
  47                                        unsigned long page_size)
  48{
  49        int rc = hv_flush_page(addr, page_size);
  50        if (rc < 0)
  51                panic("hv_flush_page(%#lx,%#lx) failed: %d",
  52                      addr, page_size, rc);
  53        if (!vma || (vma != FLUSH_NONEXEC && (vma->vm_flags & VM_EXEC)))
  54                __flush_icache();
  55}
  56
  57/* Flush range of user pages on this cpu. */
  58static inline void local_flush_tlb_pages(struct vm_area_struct *vma,
  59                                         unsigned long addr,
  60                                         unsigned long page_size,
  61                                         unsigned long len)
  62{
  63        int rc = hv_flush_pages(addr, page_size, len);
  64        if (rc < 0)
  65                panic("hv_flush_pages(%#lx,%#lx,%#lx) failed: %d",
  66                      addr, page_size, len, rc);
  67        if (!vma || (vma != FLUSH_NONEXEC && (vma->vm_flags & VM_EXEC)))
  68                __flush_icache();
  69}
  70
  71/* Flush all user pages on this cpu. */
  72static inline void local_flush_tlb(void)
  73{
  74        int rc = hv_flush_all(1);   /* preserve global mappings */
  75        if (rc < 0)
  76                panic("hv_flush_all(1) failed: %d", rc);
  77        __flush_icache();
  78}
  79
  80/*
  81 * Global pages have to be flushed a bit differently. Not a real
  82 * performance problem because this does not happen often.
  83 */
  84static inline void local_flush_tlb_all(void)
  85{
  86        int i;
  87        for (i = 0; ; ++i) {
  88                HV_VirtAddrRange r = hv_inquire_virtual(i);
  89                if (r.size == 0)
  90                        break;
  91                local_flush_tlb_pages(NULL, r.start, PAGE_SIZE, r.size);
  92                local_flush_tlb_pages(NULL, r.start, HPAGE_SIZE, r.size);
  93        }
  94}
  95
  96/*
  97 * TLB flushing:
  98 *
  99 *  - flush_tlb() flushes the current mm struct TLBs
 100 *  - flush_tlb_all() flushes all processes TLBs
 101 *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
 102 *  - flush_tlb_page(vma, vmaddr) flushes one page
 103 *  - flush_tlb_range(vma, start, end) flushes a range of pages
 104 *  - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
 105 *  - flush_tlb_others(cpumask, mm, va) flushes TLBs on other cpus
 106 *
 107 * Here (as in vm_area_struct), "end" means the first byte after
 108 * our end address.
 109 */
 110
 111extern void flush_tlb_all(void);
 112extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
 113extern void flush_tlb_current_task(void);
 114extern void flush_tlb_mm(struct mm_struct *);
 115extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
 116extern void flush_tlb_page_mm(struct vm_area_struct *,
 117                              struct mm_struct *, unsigned long);
 118extern void flush_tlb_range(struct vm_area_struct *,
 119                            unsigned long start, unsigned long end);
 120
 121#define flush_tlb()     flush_tlb_current_task()
 122
 123#endif /* _ASM_TILE_TLBFLUSH_H */
 124