diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc64/mm/imalloc.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/ppc64/mm/imalloc.c')
-rw-r--r-- | arch/ppc64/mm/imalloc.c | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/arch/ppc64/mm/imalloc.c b/arch/ppc64/mm/imalloc.c new file mode 100644 index 000000000000..9d92b0d9cde5 --- /dev/null +++ b/arch/ppc64/mm/imalloc.c | |||
@@ -0,0 +1,312 @@ | |||
1 | /* | ||
2 | * c 2001 PPC 64 Team, IBM Corp | ||
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; either version | ||
7 | * 2 of the License, or (at your option) any later version. | ||
8 | */ | ||
9 | |||
10 | #include <linux/slab.h> | ||
11 | #include <linux/vmalloc.h> | ||
12 | |||
13 | #include <asm/uaccess.h> | ||
14 | #include <asm/pgalloc.h> | ||
15 | #include <asm/pgtable.h> | ||
16 | #include <asm/semaphore.h> | ||
17 | |||
18 | static DECLARE_MUTEX(imlist_sem); | ||
19 | struct vm_struct * imlist = NULL; | ||
20 | |||
21 | static int get_free_im_addr(unsigned long size, unsigned long *im_addr) | ||
22 | { | ||
23 | unsigned long addr; | ||
24 | struct vm_struct **p, *tmp; | ||
25 | |||
26 | addr = IMALLOC_START; | ||
27 | for (p = &imlist; (tmp = *p) ; p = &tmp->next) { | ||
28 | if (size + addr < (unsigned long) tmp->addr) | ||
29 | break; | ||
30 | if ((unsigned long)tmp->addr >= IMALLOC_START) | ||
31 | addr = tmp->size + (unsigned long) tmp->addr; | ||
32 | if (addr > IMALLOC_END-size) | ||
33 | return 1; | ||
34 | } | ||
35 | *im_addr = addr; | ||
36 | |||
37 | return 0; | ||
38 | } | ||
39 | |||
40 | /* Return whether the region described by v_addr and size is a subset | ||
41 | * of the region described by parent | ||
42 | */ | ||
43 | static inline int im_region_is_subset(unsigned long v_addr, unsigned long size, | ||
44 | struct vm_struct *parent) | ||
45 | { | ||
46 | return (int) (v_addr >= (unsigned long) parent->addr && | ||
47 | v_addr < (unsigned long) parent->addr + parent->size && | ||
48 | size < parent->size); | ||
49 | } | ||
50 | |||
51 | /* Return whether the region described by v_addr and size is a superset | ||
52 | * of the region described by child | ||
53 | */ | ||
54 | static int im_region_is_superset(unsigned long v_addr, unsigned long size, | ||
55 | struct vm_struct *child) | ||
56 | { | ||
57 | struct vm_struct parent; | ||
58 | |||
59 | parent.addr = (void *) v_addr; | ||
60 | parent.size = size; | ||
61 | |||
62 | return im_region_is_subset((unsigned long) child->addr, child->size, | ||
63 | &parent); | ||
64 | } | ||
65 | |||
66 | /* Return whether the region described by v_addr and size overlaps | ||
67 | * the region described by vm. Overlapping regions meet the | ||
68 | * following conditions: | ||
69 | * 1) The regions share some part of the address space | ||
70 | * 2) The regions aren't identical | ||
71 | * 3) Neither region is a subset of the other | ||
72 | */ | ||
73 | static int im_region_overlaps(unsigned long v_addr, unsigned long size, | ||
74 | struct vm_struct *vm) | ||
75 | { | ||
76 | if (im_region_is_superset(v_addr, size, vm)) | ||
77 | return 0; | ||
78 | |||
79 | return (v_addr + size > (unsigned long) vm->addr + vm->size && | ||
80 | v_addr < (unsigned long) vm->addr + vm->size) || | ||
81 | (v_addr < (unsigned long) vm->addr && | ||
82 | v_addr + size > (unsigned long) vm->addr); | ||
83 | } | ||
84 | |||
85 | /* Determine imalloc status of region described by v_addr and size. | ||
86 | * Can return one of the following: | ||
87 | * IM_REGION_UNUSED - Entire region is unallocated in imalloc space. | ||
88 | * IM_REGION_SUBSET - Region is a subset of a region that is already | ||
89 | * allocated in imalloc space. | ||
90 | * vm will be assigned to a ptr to the parent region. | ||
91 | * IM_REGION_EXISTS - Exact region already allocated in imalloc space. | ||
92 | * vm will be assigned to a ptr to the existing imlist | ||
93 | * member. | ||
94 | * IM_REGION_OVERLAPS - Region overlaps an allocated region in imalloc space. | ||
95 | * IM_REGION_SUPERSET - Region is a superset of a region that is already | ||
96 | * allocated in imalloc space. | ||
97 | */ | ||
98 | static int im_region_status(unsigned long v_addr, unsigned long size, | ||
99 | struct vm_struct **vm) | ||
100 | { | ||
101 | struct vm_struct *tmp; | ||
102 | |||
103 | for (tmp = imlist; tmp; tmp = tmp->next) | ||
104 | if (v_addr < (unsigned long) tmp->addr + tmp->size) | ||
105 | break; | ||
106 | |||
107 | if (tmp) { | ||
108 | if (im_region_overlaps(v_addr, size, tmp)) | ||
109 | return IM_REGION_OVERLAP; | ||
110 | |||
111 | *vm = tmp; | ||
112 | if (im_region_is_subset(v_addr, size, tmp)) { | ||
113 | /* Return with tmp pointing to superset */ | ||
114 | return IM_REGION_SUBSET; | ||
115 | } | ||
116 | if (im_region_is_superset(v_addr, size, tmp)) { | ||
117 | /* Return with tmp pointing to first subset */ | ||
118 | return IM_REGION_SUPERSET; | ||
119 | } | ||
120 | else if (v_addr == (unsigned long) tmp->addr && | ||
121 | size == tmp->size) { | ||
122 | /* Return with tmp pointing to exact region */ | ||
123 | return IM_REGION_EXISTS; | ||
124 | } | ||
125 | } | ||
126 | |||
127 | *vm = NULL; | ||
128 | return IM_REGION_UNUSED; | ||
129 | } | ||
130 | |||
131 | static struct vm_struct * split_im_region(unsigned long v_addr, | ||
132 | unsigned long size, struct vm_struct *parent) | ||
133 | { | ||
134 | struct vm_struct *vm1 = NULL; | ||
135 | struct vm_struct *vm2 = NULL; | ||
136 | struct vm_struct *new_vm = NULL; | ||
137 | |||
138 | vm1 = (struct vm_struct *) kmalloc(sizeof(*vm1), GFP_KERNEL); | ||
139 | if (vm1 == NULL) { | ||
140 | printk(KERN_ERR "%s() out of memory\n", __FUNCTION__); | ||
141 | return NULL; | ||
142 | } | ||
143 | |||
144 | if (v_addr == (unsigned long) parent->addr) { | ||
145 | /* Use existing parent vm_struct to represent child, allocate | ||
146 | * new one for the remainder of parent range | ||
147 | */ | ||
148 | vm1->size = parent->size - size; | ||
149 | vm1->addr = (void *) (v_addr + size); | ||
150 | vm1->next = parent->next; | ||
151 | |||
152 | parent->size = size; | ||
153 | parent->next = vm1; | ||
154 | new_vm = parent; | ||
155 | } else if (v_addr + size == (unsigned long) parent->addr + | ||
156 | parent->size) { | ||
157 | /* Allocate new vm_struct to represent child, use existing | ||
158 | * parent one for remainder of parent range | ||
159 | */ | ||
160 | vm1->size = size; | ||
161 | vm1->addr = (void *) v_addr; | ||
162 | vm1->next = parent->next; | ||
163 | new_vm = vm1; | ||
164 | |||
165 | parent->size -= size; | ||
166 | parent->next = vm1; | ||
167 | } else { | ||
168 | /* Allocate two new vm_structs for the new child and | ||
169 | * uppermost remainder, and use existing parent one for the | ||
170 | * lower remainder of parent range | ||
171 | */ | ||
172 | vm2 = (struct vm_struct *) kmalloc(sizeof(*vm2), GFP_KERNEL); | ||
173 | if (vm2 == NULL) { | ||
174 | printk(KERN_ERR "%s() out of memory\n", __FUNCTION__); | ||
175 | kfree(vm1); | ||
176 | return NULL; | ||
177 | } | ||
178 | |||
179 | vm1->size = size; | ||
180 | vm1->addr = (void *) v_addr; | ||
181 | vm1->next = vm2; | ||
182 | new_vm = vm1; | ||
183 | |||
184 | vm2->size = ((unsigned long) parent->addr + parent->size) - | ||
185 | (v_addr + size); | ||
186 | vm2->addr = (void *) v_addr + size; | ||
187 | vm2->next = parent->next; | ||
188 | |||
189 | parent->size = v_addr - (unsigned long) parent->addr; | ||
190 | parent->next = vm1; | ||
191 | } | ||
192 | |||
193 | return new_vm; | ||
194 | } | ||
195 | |||
196 | static struct vm_struct * __add_new_im_area(unsigned long req_addr, | ||
197 | unsigned long size) | ||
198 | { | ||
199 | struct vm_struct **p, *tmp, *area; | ||
200 | |||
201 | for (p = &imlist; (tmp = *p) ; p = &tmp->next) { | ||
202 | if (req_addr + size <= (unsigned long)tmp->addr) | ||
203 | break; | ||
204 | } | ||
205 | |||
206 | area = (struct vm_struct *) kmalloc(sizeof(*area), GFP_KERNEL); | ||
207 | if (!area) | ||
208 | return NULL; | ||
209 | area->flags = 0; | ||
210 | area->addr = (void *)req_addr; | ||
211 | area->size = size; | ||
212 | area->next = *p; | ||
213 | *p = area; | ||
214 | |||
215 | return area; | ||
216 | } | ||
217 | |||
218 | static struct vm_struct * __im_get_area(unsigned long req_addr, | ||
219 | unsigned long size, | ||
220 | int criteria) | ||
221 | { | ||
222 | struct vm_struct *tmp; | ||
223 | int status; | ||
224 | |||
225 | status = im_region_status(req_addr, size, &tmp); | ||
226 | if ((criteria & status) == 0) { | ||
227 | return NULL; | ||
228 | } | ||
229 | |||
230 | switch (status) { | ||
231 | case IM_REGION_UNUSED: | ||
232 | tmp = __add_new_im_area(req_addr, size); | ||
233 | break; | ||
234 | case IM_REGION_SUBSET: | ||
235 | tmp = split_im_region(req_addr, size, tmp); | ||
236 | break; | ||
237 | case IM_REGION_EXISTS: | ||
238 | /* Return requested region */ | ||
239 | break; | ||
240 | case IM_REGION_SUPERSET: | ||
241 | /* Return first existing subset of requested region */ | ||
242 | break; | ||
243 | default: | ||
244 | printk(KERN_ERR "%s() unexpected imalloc region status\n", | ||
245 | __FUNCTION__); | ||
246 | tmp = NULL; | ||
247 | } | ||
248 | |||
249 | return tmp; | ||
250 | } | ||
251 | |||
252 | struct vm_struct * im_get_free_area(unsigned long size) | ||
253 | { | ||
254 | struct vm_struct *area; | ||
255 | unsigned long addr; | ||
256 | |||
257 | down(&imlist_sem); | ||
258 | if (get_free_im_addr(size, &addr)) { | ||
259 | printk(KERN_ERR "%s() cannot obtain addr for size 0x%lx\n", | ||
260 | __FUNCTION__, size); | ||
261 | area = NULL; | ||
262 | goto next_im_done; | ||
263 | } | ||
264 | |||
265 | area = __im_get_area(addr, size, IM_REGION_UNUSED); | ||
266 | if (area == NULL) { | ||
267 | printk(KERN_ERR | ||
268 | "%s() cannot obtain area for addr 0x%lx size 0x%lx\n", | ||
269 | __FUNCTION__, addr, size); | ||
270 | } | ||
271 | next_im_done: | ||
272 | up(&imlist_sem); | ||
273 | return area; | ||
274 | } | ||
275 | |||
276 | struct vm_struct * im_get_area(unsigned long v_addr, unsigned long size, | ||
277 | int criteria) | ||
278 | { | ||
279 | struct vm_struct *area; | ||
280 | |||
281 | down(&imlist_sem); | ||
282 | area = __im_get_area(v_addr, size, criteria); | ||
283 | up(&imlist_sem); | ||
284 | return area; | ||
285 | } | ||
286 | |||
287 | unsigned long im_free(void * addr) | ||
288 | { | ||
289 | struct vm_struct **p, *tmp; | ||
290 | unsigned long ret_size = 0; | ||
291 | |||
292 | if (!addr) | ||
293 | return ret_size; | ||
294 | if ((PAGE_SIZE-1) & (unsigned long) addr) { | ||
295 | printk(KERN_ERR "Trying to %s bad address (%p)\n", __FUNCTION__, addr); | ||
296 | return ret_size; | ||
297 | } | ||
298 | down(&imlist_sem); | ||
299 | for (p = &imlist ; (tmp = *p) ; p = &tmp->next) { | ||
300 | if (tmp->addr == addr) { | ||
301 | ret_size = tmp->size; | ||
302 | *p = tmp->next; | ||
303 | kfree(tmp); | ||
304 | up(&imlist_sem); | ||
305 | return ret_size; | ||
306 | } | ||
307 | } | ||
308 | up(&imlist_sem); | ||
309 | printk(KERN_ERR "Trying to %s nonexistent area (%p)\n", __FUNCTION__, | ||
310 | addr); | ||
311 | return ret_size; | ||
312 | } | ||