1 /*
2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
3 *
4 * Copyright (C) 2002-2011 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
6 *
7 * Created by Charles Manning <charles@aleph1.co.uk>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14 #include "yaffs_allocator.h"
15 #include "yaffs_guts.h"
16 #include "yaffs_trace.h"
17 #include "yportenv.h"
18 #include <dm/devres.h>
19
20 /*
21 * Each entry in yaffs_tnode_list and yaffs_obj_list hold blocks
22 * of approx 100 objects that are themn allocated singly.
23 * This is basically a simplified slab allocator.
24 *
25 * We don't use the Linux slab allocator because slab does not allow
26 * us to dump all the objects in one hit when we do a umount and tear
27 * down all the tnodes and objects. slab requires that we first free
28 * the individual objects.
29 *
30 * Once yaffs has been mainlined I shall try to motivate for a change
31 * to slab to provide the extra features we need here.
32 */
33
34 struct yaffs_tnode_list {
35 struct yaffs_tnode_list *next;
36 struct yaffs_tnode *tnodes;
37 };
38
39 struct yaffs_obj_list {
40 struct yaffs_obj_list *next;
41 struct yaffs_obj *objects;
42 };
43
44 struct yaffs_allocator {
45 int n_tnodes_created;
46 struct yaffs_tnode *free_tnodes;
47 int n_free_tnodes;
48 struct yaffs_tnode_list *alloc_tnode_list;
49
50 int n_obj_created;
51 struct list_head free_objs;
52 int n_free_objects;
53
54 struct yaffs_obj_list *allocated_obj_list;
55 };
56
yaffs_deinit_raw_tnodes(struct yaffs_dev * dev)57 static void yaffs_deinit_raw_tnodes(struct yaffs_dev *dev)
58 {
59 struct yaffs_allocator *allocator =
60 (struct yaffs_allocator *)dev->allocator;
61 struct yaffs_tnode_list *tmp;
62
63 if (!allocator) {
64 BUG();
65 return;
66 }
67
68 while (allocator->alloc_tnode_list) {
69 tmp = allocator->alloc_tnode_list->next;
70
71 kfree(allocator->alloc_tnode_list->tnodes);
72 kfree(allocator->alloc_tnode_list);
73 allocator->alloc_tnode_list = tmp;
74 }
75
76 allocator->free_tnodes = NULL;
77 allocator->n_free_tnodes = 0;
78 allocator->n_tnodes_created = 0;
79 }
80
yaffs_init_raw_tnodes(struct yaffs_dev * dev)81 static void yaffs_init_raw_tnodes(struct yaffs_dev *dev)
82 {
83 struct yaffs_allocator *allocator = dev->allocator;
84
85 if (!allocator) {
86 BUG();
87 return;
88 }
89
90 allocator->alloc_tnode_list = NULL;
91 allocator->free_tnodes = NULL;
92 allocator->n_free_tnodes = 0;
93 allocator->n_tnodes_created = 0;
94 }
95
yaffs_create_tnodes(struct yaffs_dev * dev,int n_tnodes)96 static int yaffs_create_tnodes(struct yaffs_dev *dev, int n_tnodes)
97 {
98 struct yaffs_allocator *allocator =
99 (struct yaffs_allocator *)dev->allocator;
100 int i;
101 struct yaffs_tnode *new_tnodes;
102 u8 *mem;
103 struct yaffs_tnode *curr;
104 struct yaffs_tnode *next;
105 struct yaffs_tnode_list *tnl;
106
107 if (!allocator) {
108 BUG();
109 return YAFFS_FAIL;
110 }
111
112 if (n_tnodes < 1)
113 return YAFFS_OK;
114
115 /* make these things */
116 new_tnodes = kmalloc(n_tnodes * dev->tnode_size, GFP_NOFS);
117 mem = (u8 *) new_tnodes;
118
119 if (!new_tnodes) {
120 yaffs_trace(YAFFS_TRACE_ERROR,
121 "yaffs: Could not allocate Tnodes");
122 return YAFFS_FAIL;
123 }
124
125 /* New hookup for wide tnodes */
126 for (i = 0; i < n_tnodes - 1; i++) {
127 curr = (struct yaffs_tnode *)&mem[i * dev->tnode_size];
128 next = (struct yaffs_tnode *)&mem[(i + 1) * dev->tnode_size];
129 curr->internal[0] = next;
130 }
131
132 curr = (struct yaffs_tnode *)&mem[(n_tnodes - 1) * dev->tnode_size];
133 curr->internal[0] = allocator->free_tnodes;
134 allocator->free_tnodes = (struct yaffs_tnode *)mem;
135
136 allocator->n_free_tnodes += n_tnodes;
137 allocator->n_tnodes_created += n_tnodes;
138
139 /* Now add this bunch of tnodes to a list for freeing up.
140 * NB If we can't add this to the management list it isn't fatal
141 * but it just means we can't free this bunch of tnodes later.
142 */
143 tnl = kmalloc(sizeof(struct yaffs_tnode_list), GFP_NOFS);
144 if (!tnl) {
145 yaffs_trace(YAFFS_TRACE_ERROR,
146 "Could not add tnodes to management list");
147 return YAFFS_FAIL;
148 } else {
149 tnl->tnodes = new_tnodes;
150 tnl->next = allocator->alloc_tnode_list;
151 allocator->alloc_tnode_list = tnl;
152 }
153
154 yaffs_trace(YAFFS_TRACE_ALLOCATE, "Tnodes added");
155
156 return YAFFS_OK;
157 }
158
yaffs_alloc_raw_tnode(struct yaffs_dev * dev)159 struct yaffs_tnode *yaffs_alloc_raw_tnode(struct yaffs_dev *dev)
160 {
161 struct yaffs_allocator *allocator =
162 (struct yaffs_allocator *)dev->allocator;
163 struct yaffs_tnode *tn = NULL;
164
165 if (!allocator) {
166 BUG();
167 return NULL;
168 }
169
170 /* If there are none left make more */
171 if (!allocator->free_tnodes)
172 yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);
173
174 if (allocator->free_tnodes) {
175 tn = allocator->free_tnodes;
176 allocator->free_tnodes = allocator->free_tnodes->internal[0];
177 allocator->n_free_tnodes--;
178 }
179
180 return tn;
181 }
182
183 /* FreeTnode frees up a tnode and puts it back on the free list */
yaffs_free_raw_tnode(struct yaffs_dev * dev,struct yaffs_tnode * tn)184 void yaffs_free_raw_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
185 {
186 struct yaffs_allocator *allocator = dev->allocator;
187
188 if (!allocator) {
189 BUG();
190 return;
191 }
192
193 if (tn) {
194 tn->internal[0] = allocator->free_tnodes;
195 allocator->free_tnodes = tn;
196 allocator->n_free_tnodes++;
197 }
198 dev->checkpoint_blocks_required = 0; /* force recalculation */
199 }
200
201 /*--------------- yaffs_obj alloaction ------------------------
202 *
203 * Free yaffs_objs are stored in a list using obj->siblings.
204 * The blocks of allocated objects are stored in a linked list.
205 */
206
yaffs_init_raw_objs(struct yaffs_dev * dev)207 static void yaffs_init_raw_objs(struct yaffs_dev *dev)
208 {
209 struct yaffs_allocator *allocator = dev->allocator;
210
211 if (!allocator) {
212 BUG();
213 return;
214 }
215
216 allocator->allocated_obj_list = NULL;
217 INIT_LIST_HEAD(&allocator->free_objs);
218 allocator->n_free_objects = 0;
219 }
220
yaffs_deinit_raw_objs(struct yaffs_dev * dev)221 static void yaffs_deinit_raw_objs(struct yaffs_dev *dev)
222 {
223 struct yaffs_allocator *allocator = dev->allocator;
224 struct yaffs_obj_list *tmp;
225
226 if (!allocator) {
227 BUG();
228 return;
229 }
230
231 while (allocator->allocated_obj_list) {
232 tmp = allocator->allocated_obj_list->next;
233 kfree(allocator->allocated_obj_list->objects);
234 kfree(allocator->allocated_obj_list);
235 allocator->allocated_obj_list = tmp;
236 }
237
238 INIT_LIST_HEAD(&allocator->free_objs);
239 allocator->n_free_objects = 0;
240 allocator->n_obj_created = 0;
241 }
242
yaffs_create_free_objs(struct yaffs_dev * dev,int n_obj)243 static int yaffs_create_free_objs(struct yaffs_dev *dev, int n_obj)
244 {
245 struct yaffs_allocator *allocator = dev->allocator;
246 int i;
247 struct yaffs_obj *new_objs;
248 struct yaffs_obj_list *list;
249
250 if (!allocator) {
251 BUG();
252 return YAFFS_FAIL;
253 }
254
255 if (n_obj < 1)
256 return YAFFS_OK;
257
258 /* make these things */
259 new_objs = kmalloc(n_obj * sizeof(struct yaffs_obj), GFP_NOFS);
260 list = kmalloc(sizeof(struct yaffs_obj_list), GFP_NOFS);
261
262 if (!new_objs || !list) {
263 kfree(new_objs);
264 new_objs = NULL;
265 kfree(list);
266 list = NULL;
267 yaffs_trace(YAFFS_TRACE_ALLOCATE,
268 "Could not allocate more objects");
269 return YAFFS_FAIL;
270 }
271
272 /* Hook them into the free list */
273 for (i = 0; i < n_obj; i++)
274 list_add(&new_objs[i].siblings, &allocator->free_objs);
275
276 allocator->n_free_objects += n_obj;
277 allocator->n_obj_created += n_obj;
278
279 /* Now add this bunch of Objects to a list for freeing up. */
280
281 list->objects = new_objs;
282 list->next = allocator->allocated_obj_list;
283 allocator->allocated_obj_list = list;
284
285 return YAFFS_OK;
286 }
287
yaffs_alloc_raw_obj(struct yaffs_dev * dev)288 struct yaffs_obj *yaffs_alloc_raw_obj(struct yaffs_dev *dev)
289 {
290 struct yaffs_obj *obj = NULL;
291 struct list_head *lh;
292 struct yaffs_allocator *allocator = dev->allocator;
293
294 if (!allocator) {
295 BUG();
296 return obj;
297 }
298
299 /* If there are none left make more */
300 if (list_empty(&allocator->free_objs))
301 yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);
302
303 if (!list_empty(&allocator->free_objs)) {
304 lh = allocator->free_objs.next;
305 obj = list_entry(lh, struct yaffs_obj, siblings);
306 list_del_init(lh);
307 allocator->n_free_objects--;
308 }
309
310 return obj;
311 }
312
yaffs_free_raw_obj(struct yaffs_dev * dev,struct yaffs_obj * obj)313 void yaffs_free_raw_obj(struct yaffs_dev *dev, struct yaffs_obj *obj)
314 {
315
316 struct yaffs_allocator *allocator = dev->allocator;
317
318 if (!allocator) {
319 BUG();
320 return;
321 }
322
323 /* Link into the free list. */
324 list_add(&obj->siblings, &allocator->free_objs);
325 allocator->n_free_objects++;
326 }
327
yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev * dev)328 void yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev *dev)
329 {
330
331 if (!dev->allocator) {
332 BUG();
333 return;
334 }
335
336 yaffs_deinit_raw_tnodes(dev);
337 yaffs_deinit_raw_objs(dev);
338 kfree(dev->allocator);
339 dev->allocator = NULL;
340 }
341
yaffs_init_raw_tnodes_and_objs(struct yaffs_dev * dev)342 void yaffs_init_raw_tnodes_and_objs(struct yaffs_dev *dev)
343 {
344 struct yaffs_allocator *allocator;
345
346 if (dev->allocator) {
347 BUG();
348 return;
349 }
350
351 allocator = kmalloc(sizeof(struct yaffs_allocator), GFP_NOFS);
352 if (allocator) {
353 dev->allocator = allocator;
354 yaffs_init_raw_tnodes(dev);
355 yaffs_init_raw_objs(dev);
356 }
357 }
358