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Diffstat (limited to 'arch/mips/mm/mmap.c')
-rw-r--r--arch/mips/mm/mmap.c111
1 files changed, 17 insertions, 94 deletions
diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c
index 302d779d5b0d..d9be7540a6be 100644
--- a/arch/mips/mm/mmap.c
+++ b/arch/mips/mm/mmap.c
@@ -45,18 +45,6 @@ static unsigned long mmap_base(unsigned long rnd)
45 return PAGE_ALIGN(TASK_SIZE - gap - rnd); 45 return PAGE_ALIGN(TASK_SIZE - gap - rnd);
46} 46}
47 47
48static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
49 unsigned long pgoff)
50{
51 unsigned long base = addr & ~shm_align_mask;
52 unsigned long off = (pgoff << PAGE_SHIFT) & shm_align_mask;
53
54 if (base + off <= addr)
55 return base + off;
56
57 return base - off;
58}
59
60#define COLOUR_ALIGN(addr, pgoff) \ 48#define COLOUR_ALIGN(addr, pgoff) \
61 ((((addr) + shm_align_mask) & ~shm_align_mask) + \ 49 ((((addr) + shm_align_mask) & ~shm_align_mask) + \
62 (((pgoff) << PAGE_SHIFT) & shm_align_mask)) 50 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
@@ -71,6 +59,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp,
71 struct vm_area_struct *vma; 59 struct vm_area_struct *vma;
72 unsigned long addr = addr0; 60 unsigned long addr = addr0;
73 int do_color_align; 61 int do_color_align;
62 struct vm_unmapped_area_info info;
74 63
75 if (unlikely(len > TASK_SIZE)) 64 if (unlikely(len > TASK_SIZE))
76 return -ENOMEM; 65 return -ENOMEM;
@@ -107,97 +96,31 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp,
107 return addr; 96 return addr;
108 } 97 }
109 98
110 if (dir == UP) { 99 info.length = len;
111 addr = mm->mmap_base; 100 info.align_mask = do_color_align ? (PAGE_MASK & shm_align_mask) : 0;
112 if (do_color_align) 101 info.align_offset = pgoff << PAGE_SHIFT;
113 addr = COLOUR_ALIGN(addr, pgoff);
114 else
115 addr = PAGE_ALIGN(addr);
116 102
117 for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) { 103 if (dir == DOWN) {
118 /* At this point: (!vma || addr < vma->vm_end). */ 104 info.flags = VM_UNMAPPED_AREA_TOPDOWN;
119 if (TASK_SIZE - len < addr) 105 info.low_limit = PAGE_SIZE;
120 return -ENOMEM; 106 info.high_limit = mm->mmap_base;
121 if (!vma || addr + len <= vma->vm_start) 107 addr = vm_unmapped_area(&info);
122 return addr; 108
123 addr = vma->vm_end; 109 if (!(addr & ~PAGE_MASK))
124 if (do_color_align) 110 return addr;
125 addr = COLOUR_ALIGN(addr, pgoff);
126 }
127 } else {
128 /* check if free_area_cache is useful for us */
129 if (len <= mm->cached_hole_size) {
130 mm->cached_hole_size = 0;
131 mm->free_area_cache = mm->mmap_base;
132 }
133 111
134 /*
135 * either no address requested, or the mapping can't fit into
136 * the requested address hole
137 */
138 addr = mm->free_area_cache;
139 if (do_color_align) {
140 unsigned long base =
141 COLOUR_ALIGN_DOWN(addr - len, pgoff);
142 addr = base + len;
143 }
144
145 /* make sure it can fit in the remaining address space */
146 if (likely(addr > len)) {
147 vma = find_vma(mm, addr - len);
148 if (!vma || addr <= vma->vm_start) {
149 /* cache the address as a hint for next time */
150 return mm->free_area_cache = addr - len;
151 }
152 }
153
154 if (unlikely(mm->mmap_base < len))
155 goto bottomup;
156
157 addr = mm->mmap_base - len;
158 if (do_color_align)
159 addr = COLOUR_ALIGN_DOWN(addr, pgoff);
160
161 do {
162 /*
163 * Lookup failure means no vma is above this address,
164 * else if new region fits below vma->vm_start,
165 * return with success:
166 */
167 vma = find_vma(mm, addr);
168 if (likely(!vma || addr + len <= vma->vm_start)) {
169 /* cache the address as a hint for next time */
170 return mm->free_area_cache = addr;
171 }
172
173 /* remember the largest hole we saw so far */
174 if (addr + mm->cached_hole_size < vma->vm_start)
175 mm->cached_hole_size = vma->vm_start - addr;
176
177 /* try just below the current vma->vm_start */
178 addr = vma->vm_start - len;
179 if (do_color_align)
180 addr = COLOUR_ALIGN_DOWN(addr, pgoff);
181 } while (likely(len < vma->vm_start));
182
183bottomup:
184 /* 112 /*
185 * A failed mmap() very likely causes application failure, 113 * A failed mmap() very likely causes application failure,
186 * so fall back to the bottom-up function here. This scenario 114 * so fall back to the bottom-up function here. This scenario
187 * can happen with large stack limits and large mmap() 115 * can happen with large stack limits and large mmap()
188 * allocations. 116 * allocations.
189 */ 117 */
190 mm->cached_hole_size = ~0UL;
191 mm->free_area_cache = TASK_UNMAPPED_BASE;
192 addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
193 /*
194 * Restore the topdown base:
195 */
196 mm->free_area_cache = mm->mmap_base;
197 mm->cached_hole_size = ~0UL;
198
199 return addr;
200 } 118 }
119
120 info.flags = 0;
121 info.low_limit = mm->mmap_base;
122 info.high_limit = TASK_SIZE;
123 return vm_unmapped_area(&info);
201} 124}
202 125
203unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0, 126unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0,
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-24 21:05:19 -0500