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 */
36 DECLARE_PER_CPU(int, current_asid);
37
38 /* The hypervisor tells us what ASIDs are available to us. */
39 extern 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. */
local_flush_tlb_page(struct vm_area_struct * vma,unsigned long addr,unsigned long page_size)45 static 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. */
local_flush_tlb_pages(struct vm_area_struct * vma,unsigned long addr,unsigned long page_size,unsigned long len)58 static 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. */
local_flush_tlb(void)72 static 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 */
local_flush_tlb_all(void)84 static 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
111 extern void flush_tlb_all(void);
112 extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
113 extern void flush_tlb_current_task(void);
114 extern void flush_tlb_mm(struct mm_struct *);
115 extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
116 extern void flush_tlb_page_mm(struct vm_area_struct *,
117 struct mm_struct *, unsigned long);
118 extern 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