2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2018 Aleph One Ltd.
6 * Created by Charles Manning <charles@aleph1.co.uk>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include "yaffs_allocator.h"
14 #include "yaffs_guts.h"
15 #include "yaffs_trace.h"
19 * Each entry in yaffs_tnode_list and yaffs_obj_list hold blocks
20 * of approx 100 objects that are themn allocated singly.
21 * This is basically a simplified slab allocator.
23 * We don't use the Linux slab allocator because slab does not allow
24 * us to dump all the objects in one hit when we do a umount and tear
25 * down all the tnodes and objects. slab requires that we first free
26 * the individual objects.
28 * Once yaffs has been mainlined I shall try to motivate for a change
29 * to slab to provide the extra features we need here.
32 struct yaffs_tnode_list {
33 struct yaffs_tnode_list *next;
34 struct yaffs_tnode *tnodes;
37 struct yaffs_obj_list {
38 struct yaffs_obj_list *next;
39 struct yaffs_obj *objects;
42 struct yaffs_allocator {
44 struct yaffs_tnode *free_tnodes;
46 struct yaffs_tnode_list *alloc_tnode_list;
49 struct list_head free_objs;
52 struct yaffs_obj_list *allocated_obj_list;
55 static void yaffs_deinit_raw_tnodes(struct yaffs_dev *dev)
57 struct yaffs_allocator *allocator =
58 (struct yaffs_allocator *)dev->allocator;
59 struct yaffs_tnode_list *tmp;
66 while (allocator->alloc_tnode_list) {
67 tmp = allocator->alloc_tnode_list->next;
69 kfree(allocator->alloc_tnode_list->tnodes);
70 kfree(allocator->alloc_tnode_list);
71 allocator->alloc_tnode_list = tmp;
74 allocator->free_tnodes = NULL;
75 allocator->n_free_tnodes = 0;
76 allocator->n_tnodes_created = 0;
79 static void yaffs_init_raw_tnodes(struct yaffs_dev *dev)
81 struct yaffs_allocator *allocator = dev->allocator;
88 allocator->alloc_tnode_list = NULL;
89 allocator->free_tnodes = NULL;
90 allocator->n_free_tnodes = 0;
91 allocator->n_tnodes_created = 0;
94 static int yaffs_create_tnodes(struct yaffs_dev *dev, int n_tnodes)
96 struct yaffs_allocator *allocator =
97 (struct yaffs_allocator *)dev->allocator;
99 struct yaffs_tnode *new_tnodes;
101 struct yaffs_tnode *curr;
102 struct yaffs_tnode *next;
103 struct yaffs_tnode_list *tnl;
113 /* make these things */
114 new_tnodes = kmalloc(n_tnodes * dev->tnode_size, GFP_NOFS);
115 mem = (u8 *) new_tnodes;
118 yaffs_trace(YAFFS_TRACE_ERROR,
119 "yaffs: Could not allocate Tnodes");
123 /* New hookup for wide tnodes */
124 for (i = 0; i < n_tnodes - 1; i++) {
125 curr = (struct yaffs_tnode *)&mem[i * dev->tnode_size];
126 next = (struct yaffs_tnode *)&mem[(i + 1) * dev->tnode_size];
127 curr->internal[0] = next;
130 curr = (struct yaffs_tnode *)&mem[(n_tnodes - 1) * dev->tnode_size];
131 curr->internal[0] = allocator->free_tnodes;
132 allocator->free_tnodes = (struct yaffs_tnode *)mem;
134 allocator->n_free_tnodes += n_tnodes;
135 allocator->n_tnodes_created += n_tnodes;
137 /* Now add this bunch of tnodes to a list for freeing up.
138 * NB If we can't add this to the management list it isn't fatal
139 * but it just means we can't free this bunch of tnodes later.
141 tnl = kmalloc(sizeof(struct yaffs_tnode_list), GFP_NOFS);
143 yaffs_trace(YAFFS_TRACE_ERROR,
144 "Could not add tnodes to management list");
147 tnl->tnodes = new_tnodes;
148 tnl->next = allocator->alloc_tnode_list;
149 allocator->alloc_tnode_list = tnl;
152 yaffs_trace(YAFFS_TRACE_ALLOCATE, "Tnodes added");
157 struct yaffs_tnode *yaffs_alloc_raw_tnode(struct yaffs_dev *dev)
159 struct yaffs_allocator *allocator =
160 (struct yaffs_allocator *)dev->allocator;
161 struct yaffs_tnode *tn = NULL;
168 /* If there are none left make more */
169 if (!allocator->free_tnodes)
170 yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);
172 if (allocator->free_tnodes) {
173 tn = allocator->free_tnodes;
174 allocator->free_tnodes = allocator->free_tnodes->internal[0];
175 allocator->n_free_tnodes--;
181 /* FreeTnode frees up a tnode and puts it back on the free list */
182 void yaffs_free_raw_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
184 struct yaffs_allocator *allocator = dev->allocator;
192 tn->internal[0] = allocator->free_tnodes;
193 allocator->free_tnodes = tn;
194 allocator->n_free_tnodes++;
196 dev->checkpoint_blocks_required = 0; /* force recalculation */
199 /*--------------- yaffs_obj alloaction ------------------------
201 * Free yaffs_objs are stored in a list using obj->siblings.
202 * The blocks of allocated objects are stored in a linked list.
205 static void yaffs_init_raw_objs(struct yaffs_dev *dev)
207 struct yaffs_allocator *allocator = dev->allocator;
214 allocator->allocated_obj_list = NULL;
215 INIT_LIST_HEAD(&allocator->free_objs);
216 allocator->n_free_objects = 0;
219 static void yaffs_deinit_raw_objs(struct yaffs_dev *dev)
221 struct yaffs_allocator *allocator = dev->allocator;
222 struct yaffs_obj_list *tmp;
229 while (allocator->allocated_obj_list) {
230 tmp = allocator->allocated_obj_list->next;
231 kfree(allocator->allocated_obj_list->objects);
232 kfree(allocator->allocated_obj_list);
233 allocator->allocated_obj_list = tmp;
236 INIT_LIST_HEAD(&allocator->free_objs);
237 allocator->n_free_objects = 0;
238 allocator->n_obj_created = 0;
241 static int yaffs_create_free_objs(struct yaffs_dev *dev, int n_obj)
243 struct yaffs_allocator *allocator = dev->allocator;
245 struct yaffs_obj *new_objs;
246 struct yaffs_obj_list *list;
256 /* make these things */
257 new_objs = kmalloc(n_obj * sizeof(struct yaffs_obj), GFP_NOFS);
258 list = kmalloc(sizeof(struct yaffs_obj_list), GFP_NOFS);
260 if (!new_objs || !list) {
265 yaffs_trace(YAFFS_TRACE_ALLOCATE,
266 "Could not allocate more objects");
270 /* Hook them into the free list */
271 for (i = 0; i < n_obj; i++)
272 list_add(&new_objs[i].siblings, &allocator->free_objs);
274 allocator->n_free_objects += n_obj;
275 allocator->n_obj_created += n_obj;
277 /* Now add this bunch of Objects to a list for freeing up. */
279 list->objects = new_objs;
280 list->next = allocator->allocated_obj_list;
281 allocator->allocated_obj_list = list;
286 struct yaffs_obj *yaffs_alloc_raw_obj(struct yaffs_dev *dev)
288 struct yaffs_obj *obj = NULL;
289 struct list_head *lh;
290 struct yaffs_allocator *allocator = dev->allocator;
297 /* If there are none left make more */
298 if (list_empty(&allocator->free_objs))
299 yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);
301 if (!list_empty(&allocator->free_objs)) {
302 lh = allocator->free_objs.next;
303 obj = list_entry(lh, struct yaffs_obj, siblings);
305 allocator->n_free_objects--;
311 void yaffs_free_raw_obj(struct yaffs_dev *dev, struct yaffs_obj *obj)
314 struct yaffs_allocator *allocator = dev->allocator;
321 /* Link into the free list. */
322 list_add(&obj->siblings, &allocator->free_objs);
323 allocator->n_free_objects++;
326 void yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev *dev)
329 if (!dev->allocator) {
334 yaffs_deinit_raw_tnodes(dev);
335 yaffs_deinit_raw_objs(dev);
336 kfree(dev->allocator);
337 dev->allocator = NULL;
340 void yaffs_init_raw_tnodes_and_objs(struct yaffs_dev *dev)
342 struct yaffs_allocator *allocator;
344 if (dev->allocator) {
349 allocator = kmalloc(sizeof(struct yaffs_allocator), GFP_NOFS);
351 dev->allocator = allocator;
352 yaffs_init_raw_tnodes(dev);
353 yaffs_init_raw_objs(dev);