ia64/xen-unstable

view linux-2.6-xen-sparse/include/asm-x86_64/mach-xen/asm/pgalloc.h @ 15225:ca62b4b4f762

LINUX/x86_64: Cleanup 15129:a40967e39652 by using __pgd rather than
abusing mk_kernel_pgd.

Also set the user bit on the vsyscall entry in the user pgd.

Both changes suggested by Jan Beulich.

Signed-off-by: Ian Campbell <ian.campbell@xensource.com>
author Ian Campbell <ian.campbell@xensource.com>
date Fri May 25 11:24:02 2007 +0100 (2007-05-25)
parents 8475a4e0425e
children
line source
1 #ifndef _X86_64_PGALLOC_H
2 #define _X86_64_PGALLOC_H
4 #include <asm/fixmap.h>
5 #include <asm/pda.h>
6 #include <linux/threads.h>
7 #include <linux/mm.h>
8 #include <asm/io.h> /* for phys_to_virt and page_to_pseudophys */
10 #include <xen/features.h>
11 void make_page_readonly(void *va, unsigned int feature);
12 void make_page_writable(void *va, unsigned int feature);
13 void make_pages_readonly(void *va, unsigned int nr, unsigned int feature);
14 void make_pages_writable(void *va, unsigned int nr, unsigned int feature);
16 #define __user_pgd(pgd) ((pgd) + PTRS_PER_PGD)
18 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
19 {
20 set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)));
21 }
23 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *pte)
24 {
25 if (unlikely((mm)->context.pinned)) {
26 BUG_ON(HYPERVISOR_update_va_mapping(
27 (unsigned long)__va(page_to_pfn(pte) << PAGE_SHIFT),
28 pfn_pte(page_to_pfn(pte), PAGE_KERNEL_RO), 0));
29 set_pmd(pmd, __pmd(_PAGE_TABLE | (page_to_pfn(pte) << PAGE_SHIFT)));
30 } else {
31 *(pmd) = __pmd(_PAGE_TABLE | (page_to_pfn(pte) << PAGE_SHIFT));
32 }
33 }
35 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
36 {
37 if (unlikely((mm)->context.pinned)) {
38 BUG_ON(HYPERVISOR_update_va_mapping(
39 (unsigned long)pmd,
40 pfn_pte(virt_to_phys(pmd)>>PAGE_SHIFT,
41 PAGE_KERNEL_RO), 0));
42 set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
43 } else {
44 *(pud) = __pud(_PAGE_TABLE | __pa(pmd));
45 }
46 }
48 /*
49 * We need to use the batch mode here, but pgd_pupulate() won't be
50 * be called frequently.
51 */
52 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
53 {
54 if (unlikely((mm)->context.pinned)) {
55 BUG_ON(HYPERVISOR_update_va_mapping(
56 (unsigned long)pud,
57 pfn_pte(virt_to_phys(pud)>>PAGE_SHIFT,
58 PAGE_KERNEL_RO), 0));
59 set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)));
60 set_pgd(__user_pgd(pgd), __pgd(_PAGE_TABLE | __pa(pud)));
61 } else {
62 *(pgd) = __pgd(_PAGE_TABLE | __pa(pud));
63 *(__user_pgd(pgd)) = *(pgd);
64 }
65 }
67 extern struct page *pte_alloc_one(struct mm_struct *mm, unsigned long addr);
68 extern void pte_free(struct page *pte);
70 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
71 {
72 struct page *pg;
74 pg = pte_alloc_one(mm, addr);
75 return pg ? page_address(pg) : NULL;
76 }
78 static inline void pmd_free(pmd_t *pmd)
79 {
80 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
81 pte_free(virt_to_page(pmd));
82 }
84 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
85 {
86 struct page *pg;
88 pg = pte_alloc_one(mm, addr);
89 return pg ? page_address(pg) : NULL;
90 }
92 static inline void pud_free(pud_t *pud)
93 {
94 BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
95 pte_free(virt_to_page(pud));
96 }
98 static inline void pgd_list_add(pgd_t *pgd)
99 {
100 struct page *page = virt_to_page(pgd);
102 spin_lock(&pgd_lock);
103 page->index = (pgoff_t)pgd_list;
104 if (pgd_list)
105 pgd_list->private = (unsigned long)&page->index;
106 pgd_list = page;
107 page->private = (unsigned long)&pgd_list;
108 spin_unlock(&pgd_lock);
109 }
111 static inline void pgd_list_del(pgd_t *pgd)
112 {
113 struct page *next, **pprev, *page = virt_to_page(pgd);
115 spin_lock(&pgd_lock);
116 next = (struct page *)page->index;
117 pprev = (struct page **)page->private;
118 *pprev = next;
119 if (next)
120 next->private = (unsigned long)pprev;
121 spin_unlock(&pgd_lock);
122 }
124 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
125 {
126 /*
127 * We allocate two contiguous pages for kernel and user.
128 */
129 unsigned boundary;
130 pgd_t *pgd = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_REPEAT, 1);
131 if (!pgd)
132 return NULL;
133 pgd_list_add(pgd);
134 /*
135 * Copy kernel pointers in from init.
136 * Could keep a freelist or slab cache of those because the kernel
137 * part never changes.
138 */
139 boundary = pgd_index(__PAGE_OFFSET);
140 memset(pgd, 0, boundary * sizeof(pgd_t));
141 memcpy(pgd + boundary,
142 init_level4_pgt + boundary,
143 (PTRS_PER_PGD - boundary) * sizeof(pgd_t));
145 memset(__user_pgd(pgd), 0, PAGE_SIZE); /* clean up user pgd */
146 /*
147 * Set level3_user_pgt for vsyscall area
148 */
149 set_pgd(__user_pgd(pgd) + pgd_index(VSYSCALL_START),
150 __pgd(__pa_symbol(level3_user_pgt) | _PAGE_TABLE));
151 return pgd;
152 }
154 static inline void pgd_free(pgd_t *pgd)
155 {
156 pte_t *ptep = virt_to_ptep(pgd);
158 if (!pte_write(*ptep)) {
159 xen_pgd_unpin(__pa(pgd));
160 BUG_ON(HYPERVISOR_update_va_mapping(
161 (unsigned long)pgd,
162 pfn_pte(virt_to_phys(pgd)>>PAGE_SHIFT, PAGE_KERNEL),
163 0));
164 }
166 ptep = virt_to_ptep(__user_pgd(pgd));
168 if (!pte_write(*ptep)) {
169 xen_pgd_unpin(__pa(__user_pgd(pgd)));
170 BUG_ON(HYPERVISOR_update_va_mapping(
171 (unsigned long)__user_pgd(pgd),
172 pfn_pte(virt_to_phys(__user_pgd(pgd))>>PAGE_SHIFT,
173 PAGE_KERNEL),
174 0));
175 }
177 pgd_list_del(pgd);
178 free_pages((unsigned long)pgd, 1);
179 }
181 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
182 {
183 pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
184 if (pte)
185 make_page_readonly(pte, XENFEAT_writable_page_tables);
187 return pte;
188 }
190 /* Should really implement gc for free page table pages. This could be
191 done with a reference count in struct page. */
193 static inline void pte_free_kernel(pte_t *pte)
194 {
195 BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
196 make_page_writable(pte, XENFEAT_writable_page_tables);
197 free_page((unsigned long)pte);
198 }
200 #define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
201 #define __pmd_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
202 #define __pud_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
204 #endif /* _X86_64_PGALLOC_H */