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1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/kernel.h>
16#include <linux/sched.h>
17#include <linux/slab.h>
18#include <linux/vmalloc.h>
19#include <linux/mtd/mtd.h>
20#include "nodelist.h"
21
22static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *,
23 struct jffs2_inode_cache *, struct jffs2_full_dirent **);
24
25static inline struct jffs2_inode_cache *
26first_inode_chain(int *i, struct jffs2_sb_info *c)
27{
28 for (; *i < c->inocache_hashsize; (*i)++) {
29 if (c->inocache_list[*i])
30 return c->inocache_list[*i];
31 }
32 return NULL;
33}
34
35static inline struct jffs2_inode_cache *
36next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c)
37{
38 /* More in this chain? */
39 if (ic->next)
40 return ic->next;
41 (*i)++;
42 return first_inode_chain(i, c);
43}
44
45#define for_each_inode(i, c, ic) \
46 for (i = 0, ic = first_inode_chain(&i, (c)); \
47 ic; \
48 ic = next_inode(&i, ic, (c)))
49
50
51static void jffs2_build_inode_pass1(struct jffs2_sb_info *c,
52 struct jffs2_inode_cache *ic)
53{
54 struct jffs2_full_dirent *fd;
55
56 dbg_fsbuild("building directory inode #%u\n", ic->ino);
57
58 /* For each child, increase nlink */
59 for(fd = ic->scan_dents; fd; fd = fd->next) {
60 struct jffs2_inode_cache *child_ic;
61 if (!fd->ino)
62 continue;
63
64 /* we can get high latency here with huge directories */
65
66 child_ic = jffs2_get_ino_cache(c, fd->ino);
67 if (!child_ic) {
68 dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
69 fd->name, fd->ino, ic->ino);
70 jffs2_mark_node_obsolete(c, fd->raw);
71 continue;
72 }
73
74 if (fd->type == DT_DIR) {
75 if (child_ic->pino_nlink) {
76 JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n",
77 fd->name, fd->ino, ic->ino);
78 /* TODO: What do we do about it? */
79 } else {
80 child_ic->pino_nlink = ic->ino;
81 }
82 } else
83 child_ic->pino_nlink++;
84
85 dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino);
86 /* Can't free scan_dents so far. We might need them in pass 2 */
87 }
88}
89
90/* Scan plan:
91 - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go
92 - Scan directory tree from top down, setting nlink in inocaches
93 - Scan inocaches for inodes with nlink==0
94*/
95static int jffs2_build_filesystem(struct jffs2_sb_info *c)
96{
97 int ret;
98 int i;
99 struct jffs2_inode_cache *ic;
100 struct jffs2_full_dirent *fd;
101 struct jffs2_full_dirent *dead_fds = NULL;
102
103 dbg_fsbuild("build FS data structures\n");
104
105 /* First, scan the medium and build all the inode caches with
106 lists of physical nodes */
107
108 c->flags |= JFFS2_SB_FLAG_SCANNING;
109 ret = jffs2_scan_medium(c);
110 c->flags &= ~JFFS2_SB_FLAG_SCANNING;
111 if (ret)
112 goto exit;
113
114 dbg_fsbuild("scanned flash completely\n");
115 jffs2_dbg_dump_block_lists_nolock(c);
116
117 dbg_fsbuild("pass 1 starting\n");
118 c->flags |= JFFS2_SB_FLAG_BUILDING;
119 /* Now scan the directory tree, increasing nlink according to every dirent found. */
120 for_each_inode(i, c, ic) {
121 if (ic->scan_dents) {
122 jffs2_build_inode_pass1(c, ic);
123 cond_resched();
124 }
125 }
126
127 dbg_fsbuild("pass 1 complete\n");
128
129 /* Next, scan for inodes with nlink == 0 and remove them. If
130 they were directories, then decrement the nlink of their
131 children too, and repeat the scan. As that's going to be
132 a fairly uncommon occurrence, it's not so evil to do it this
133 way. Recursion bad. */
134 dbg_fsbuild("pass 2 starting\n");
135
136 for_each_inode(i, c, ic) {
137 if (ic->pino_nlink)
138 continue;
139
140 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
141 cond_resched();
142 }
143
144 dbg_fsbuild("pass 2a starting\n");
145
146 while (dead_fds) {
147 fd = dead_fds;
148 dead_fds = fd->next;
149
150 ic = jffs2_get_ino_cache(c, fd->ino);
151
152 if (ic)
153 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
154 jffs2_free_full_dirent(fd);
155 }
156
157 dbg_fsbuild("pass 2a complete\n");
158 dbg_fsbuild("freeing temporary data structures\n");
159
160 /* Finally, we can scan again and free the dirent structs */
161 for_each_inode(i, c, ic) {
162 while(ic->scan_dents) {
163 fd = ic->scan_dents;
164 ic->scan_dents = fd->next;
165 jffs2_free_full_dirent(fd);
166 }
167 ic->scan_dents = NULL;
168 cond_resched();
169 }
170 jffs2_build_xattr_subsystem(c);
171 c->flags &= ~JFFS2_SB_FLAG_BUILDING;
172
173 dbg_fsbuild("FS build complete\n");
174
175 /* Rotate the lists by some number to ensure wear levelling */
176 jffs2_rotate_lists(c);
177
178 ret = 0;
179
180exit:
181 if (ret) {
182 for_each_inode(i, c, ic) {
183 while(ic->scan_dents) {
184 fd = ic->scan_dents;
185 ic->scan_dents = fd->next;
186 jffs2_free_full_dirent(fd);
187 }
188 }
189 jffs2_clear_xattr_subsystem(c);
190 }
191
192 return ret;
193}
194
195static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c,
196 struct jffs2_inode_cache *ic,
197 struct jffs2_full_dirent **dead_fds)
198{
199 struct jffs2_raw_node_ref *raw;
200 struct jffs2_full_dirent *fd;
201
202 dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino);
203
204 raw = ic->nodes;
205 while (raw != (void *)ic) {
206 struct jffs2_raw_node_ref *next = raw->next_in_ino;
207 dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw));
208 jffs2_mark_node_obsolete(c, raw);
209 raw = next;
210 }
211
212 if (ic->scan_dents) {
213 int whinged = 0;
214 dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino);
215
216 while(ic->scan_dents) {
217 struct jffs2_inode_cache *child_ic;
218
219 fd = ic->scan_dents;
220 ic->scan_dents = fd->next;
221
222 if (!fd->ino) {
223 /* It's a deletion dirent. Ignore it */
224 dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name);
225 jffs2_free_full_dirent(fd);
226 continue;
227 }
228 if (!whinged)
229 whinged = 1;
230
231 dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino);
232
233 child_ic = jffs2_get_ino_cache(c, fd->ino);
234 if (!child_ic) {
235 dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n",
236 fd->name, fd->ino);
237 jffs2_free_full_dirent(fd);
238 continue;
239 }
240
241 /* Reduce nlink of the child. If it's now zero, stick it on the
242 dead_fds list to be cleaned up later. Else just free the fd */
243
244 if (fd->type == DT_DIR)
245 child_ic->pino_nlink = 0;
246 else
247 child_ic->pino_nlink--;
248
249 if (!child_ic->pino_nlink) {
250 dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n",
251 fd->ino, fd->name);
252 fd->next = *dead_fds;
253 *dead_fds = fd;
254 } else {
255 dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
256 fd->ino, fd->name, child_ic->pino_nlink);
257 jffs2_free_full_dirent(fd);
258 }
259 }
260 }
261
262 /*
263 We don't delete the inocache from the hash list and free it yet.
264 The erase code will do that, when all the nodes are completely gone.
265 */
266}
267
268static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c)
269{
270 uint32_t size;
271
272 /* Deletion should almost _always_ be allowed. We're fairly
273 buggered once we stop allowing people to delete stuff
274 because there's not enough free space... */
275 c->resv_blocks_deletion = 2;
276
277 /* Be conservative about how much space we need before we allow writes.
278 On top of that which is required for deletia, require an extra 2%
279 of the medium to be available, for overhead caused by nodes being
280 split across blocks, etc. */
281
282 size = c->flash_size / 50; /* 2% of flash size */
283 size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */
284 size += c->sector_size - 1; /* ... and round up */
285
286 c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
287
288 /* When do we let the GC thread run in the background */
289
290 c->resv_blocks_gctrigger = c->resv_blocks_write + 1;
291
292 /* When do we allow garbage collection to merge nodes to make
293 long-term progress at the expense of short-term space exhaustion? */
294 c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1;
295
296 /* When do we allow garbage collection to eat from bad blocks rather
297 than actually making progress? */
298 c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2;
299
300 /* What number of 'very dirty' eraseblocks do we allow before we
301 trigger the GC thread even if we don't _need_ the space. When we
302 can't mark nodes obsolete on the medium, the old dirty nodes cause
303 performance problems because we have to inspect and discard them. */
304 c->vdirty_blocks_gctrigger = c->resv_blocks_gctrigger;
305 if (jffs2_can_mark_obsolete(c))
306 c->vdirty_blocks_gctrigger *= 10;
307
308 /* If there's less than this amount of dirty space, don't bother
309 trying to GC to make more space. It'll be a fruitless task */
310 c->nospc_dirty_size = c->sector_size + (c->flash_size / 100);
311
312 dbg_fsbuild("trigger levels (size %d KiB, block size %d KiB, %d blocks)\n",
313 c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks);
314 dbg_fsbuild("Blocks required to allow deletion: %d (%d KiB)\n",
315 c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024);
316 dbg_fsbuild("Blocks required to allow writes: %d (%d KiB)\n",
317 c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024);
318 dbg_fsbuild("Blocks required to quiesce GC thread: %d (%d KiB)\n",
319 c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024);
320 dbg_fsbuild("Blocks required to allow GC merges: %d (%d KiB)\n",
321 c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024);
322 dbg_fsbuild("Blocks required to GC bad blocks: %d (%d KiB)\n",
323 c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024);
324 dbg_fsbuild("Amount of dirty space required to GC: %d bytes\n",
325 c->nospc_dirty_size);
326 dbg_fsbuild("Very dirty blocks before GC triggered: %d\n",
327 c->vdirty_blocks_gctrigger);
328}
329
330int jffs2_do_mount_fs(struct jffs2_sb_info *c)
331{
332 int ret;
333 int i;
334 int size;
335
336 c->free_size = c->flash_size;
337 c->nr_blocks = c->flash_size / c->sector_size;
338 size = sizeof(struct jffs2_eraseblock) * c->nr_blocks;
339#ifndef __ECOS
340 if (jffs2_blocks_use_vmalloc(c))
341 c->blocks = vzalloc(size);
342 else
343#endif
344 c->blocks = kzalloc(size, GFP_KERNEL);
345 if (!c->blocks)
346 return -ENOMEM;
347
348 for (i=0; i<c->nr_blocks; i++) {
349 INIT_LIST_HEAD(&c->blocks[i].list);
350 c->blocks[i].offset = i * c->sector_size;
351 c->blocks[i].free_size = c->sector_size;
352 }
353
354 INIT_LIST_HEAD(&c->clean_list);
355 INIT_LIST_HEAD(&c->very_dirty_list);
356 INIT_LIST_HEAD(&c->dirty_list);
357 INIT_LIST_HEAD(&c->erasable_list);
358 INIT_LIST_HEAD(&c->erasing_list);
359 INIT_LIST_HEAD(&c->erase_checking_list);
360 INIT_LIST_HEAD(&c->erase_pending_list);
361 INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
362 INIT_LIST_HEAD(&c->erase_complete_list);
363 INIT_LIST_HEAD(&c->free_list);
364 INIT_LIST_HEAD(&c->bad_list);
365 INIT_LIST_HEAD(&c->bad_used_list);
366 c->highest_ino = 1;
367 c->summary = NULL;
368
369 ret = jffs2_sum_init(c);
370 if (ret)
371 goto out_free;
372
373 if (jffs2_build_filesystem(c)) {
374 dbg_fsbuild("build_fs failed\n");
375 jffs2_free_ino_caches(c);
376 jffs2_free_raw_node_refs(c);
377 ret = -EIO;
378 goto out_free;
379 }
380
381 jffs2_calc_trigger_levels(c);
382
383 return 0;
384
385 out_free:
386#ifndef __ECOS
387 if (jffs2_blocks_use_vmalloc(c))
388 vfree(c->blocks);
389 else
390#endif
391 kfree(c->blocks);
392
393 return ret;
394}
1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
11 */
12
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/slab.h>
16#include <linux/vmalloc.h>
17#include <linux/mtd/mtd.h>
18#include "nodelist.h"
19
20static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *,
21 struct jffs2_inode_cache *, struct jffs2_full_dirent **);
22
23static inline struct jffs2_inode_cache *
24first_inode_chain(int *i, struct jffs2_sb_info *c)
25{
26 for (; *i < c->inocache_hashsize; (*i)++) {
27 if (c->inocache_list[*i])
28 return c->inocache_list[*i];
29 }
30 return NULL;
31}
32
33static inline struct jffs2_inode_cache *
34next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c)
35{
36 /* More in this chain? */
37 if (ic->next)
38 return ic->next;
39 (*i)++;
40 return first_inode_chain(i, c);
41}
42
43#define for_each_inode(i, c, ic) \
44 for (i = 0, ic = first_inode_chain(&i, (c)); \
45 ic; \
46 ic = next_inode(&i, ic, (c)))
47
48
49static void jffs2_build_inode_pass1(struct jffs2_sb_info *c,
50 struct jffs2_inode_cache *ic)
51{
52 struct jffs2_full_dirent *fd;
53
54 dbg_fsbuild("building directory inode #%u\n", ic->ino);
55
56 /* For each child, increase nlink */
57 for(fd = ic->scan_dents; fd; fd = fd->next) {
58 struct jffs2_inode_cache *child_ic;
59 if (!fd->ino)
60 continue;
61
62 /* we can get high latency here with huge directories */
63
64 child_ic = jffs2_get_ino_cache(c, fd->ino);
65 if (!child_ic) {
66 dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
67 fd->name, fd->ino, ic->ino);
68 jffs2_mark_node_obsolete(c, fd->raw);
69 continue;
70 }
71
72 if (fd->type == DT_DIR) {
73 if (child_ic->pino_nlink) {
74 JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n",
75 fd->name, fd->ino, ic->ino);
76 /* TODO: What do we do about it? */
77 } else {
78 child_ic->pino_nlink = ic->ino;
79 }
80 } else
81 child_ic->pino_nlink++;
82
83 dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino);
84 /* Can't free scan_dents so far. We might need them in pass 2 */
85 }
86}
87
88/* Scan plan:
89 - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go
90 - Scan directory tree from top down, setting nlink in inocaches
91 - Scan inocaches for inodes with nlink==0
92*/
93static int jffs2_build_filesystem(struct jffs2_sb_info *c)
94{
95 int ret;
96 int i;
97 struct jffs2_inode_cache *ic;
98 struct jffs2_full_dirent *fd;
99 struct jffs2_full_dirent *dead_fds = NULL;
100
101 dbg_fsbuild("build FS data structures\n");
102
103 /* First, scan the medium and build all the inode caches with
104 lists of physical nodes */
105
106 c->flags |= JFFS2_SB_FLAG_SCANNING;
107 ret = jffs2_scan_medium(c);
108 c->flags &= ~JFFS2_SB_FLAG_SCANNING;
109 if (ret)
110 goto exit;
111
112 dbg_fsbuild("scanned flash completely\n");
113 jffs2_dbg_dump_block_lists_nolock(c);
114
115 dbg_fsbuild("pass 1 starting\n");
116 c->flags |= JFFS2_SB_FLAG_BUILDING;
117 /* Now scan the directory tree, increasing nlink according to every dirent found. */
118 for_each_inode(i, c, ic) {
119 if (ic->scan_dents) {
120 jffs2_build_inode_pass1(c, ic);
121 cond_resched();
122 }
123 }
124
125 dbg_fsbuild("pass 1 complete\n");
126
127 /* Next, scan for inodes with nlink == 0 and remove them. If
128 they were directories, then decrement the nlink of their
129 children too, and repeat the scan. As that's going to be
130 a fairly uncommon occurrence, it's not so evil to do it this
131 way. Recursion bad. */
132 dbg_fsbuild("pass 2 starting\n");
133
134 for_each_inode(i, c, ic) {
135 if (ic->pino_nlink)
136 continue;
137
138 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
139 cond_resched();
140 }
141
142 dbg_fsbuild("pass 2a starting\n");
143
144 while (dead_fds) {
145 fd = dead_fds;
146 dead_fds = fd->next;
147
148 ic = jffs2_get_ino_cache(c, fd->ino);
149
150 if (ic)
151 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
152 jffs2_free_full_dirent(fd);
153 }
154
155 dbg_fsbuild("pass 2a complete\n");
156 dbg_fsbuild("freeing temporary data structures\n");
157
158 /* Finally, we can scan again and free the dirent structs */
159 for_each_inode(i, c, ic) {
160 while(ic->scan_dents) {
161 fd = ic->scan_dents;
162 ic->scan_dents = fd->next;
163 jffs2_free_full_dirent(fd);
164 }
165 ic->scan_dents = NULL;
166 cond_resched();
167 }
168 jffs2_build_xattr_subsystem(c);
169 c->flags &= ~JFFS2_SB_FLAG_BUILDING;
170
171 dbg_fsbuild("FS build complete\n");
172
173 /* Rotate the lists by some number to ensure wear levelling */
174 jffs2_rotate_lists(c);
175
176 ret = 0;
177
178exit:
179 if (ret) {
180 for_each_inode(i, c, ic) {
181 while(ic->scan_dents) {
182 fd = ic->scan_dents;
183 ic->scan_dents = fd->next;
184 jffs2_free_full_dirent(fd);
185 }
186 }
187 jffs2_clear_xattr_subsystem(c);
188 }
189
190 return ret;
191}
192
193static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c,
194 struct jffs2_inode_cache *ic,
195 struct jffs2_full_dirent **dead_fds)
196{
197 struct jffs2_raw_node_ref *raw;
198 struct jffs2_full_dirent *fd;
199
200 dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino);
201
202 raw = ic->nodes;
203 while (raw != (void *)ic) {
204 struct jffs2_raw_node_ref *next = raw->next_in_ino;
205 dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw));
206 jffs2_mark_node_obsolete(c, raw);
207 raw = next;
208 }
209
210 if (ic->scan_dents) {
211 int whinged = 0;
212 dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino);
213
214 while(ic->scan_dents) {
215 struct jffs2_inode_cache *child_ic;
216
217 fd = ic->scan_dents;
218 ic->scan_dents = fd->next;
219
220 if (!fd->ino) {
221 /* It's a deletion dirent. Ignore it */
222 dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name);
223 jffs2_free_full_dirent(fd);
224 continue;
225 }
226 if (!whinged)
227 whinged = 1;
228
229 dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino);
230
231 child_ic = jffs2_get_ino_cache(c, fd->ino);
232 if (!child_ic) {
233 dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n",
234 fd->name, fd->ino);
235 jffs2_free_full_dirent(fd);
236 continue;
237 }
238
239 /* Reduce nlink of the child. If it's now zero, stick it on the
240 dead_fds list to be cleaned up later. Else just free the fd */
241
242 if (fd->type == DT_DIR)
243 child_ic->pino_nlink = 0;
244 else
245 child_ic->pino_nlink--;
246
247 if (!child_ic->pino_nlink) {
248 dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n",
249 fd->ino, fd->name);
250 fd->next = *dead_fds;
251 *dead_fds = fd;
252 } else {
253 dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
254 fd->ino, fd->name, child_ic->pino_nlink);
255 jffs2_free_full_dirent(fd);
256 }
257 }
258 }
259
260 /*
261 We don't delete the inocache from the hash list and free it yet.
262 The erase code will do that, when all the nodes are completely gone.
263 */
264}
265
266static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c)
267{
268 uint32_t size;
269
270 /* Deletion should almost _always_ be allowed. We're fairly
271 buggered once we stop allowing people to delete stuff
272 because there's not enough free space... */
273 c->resv_blocks_deletion = 2;
274
275 /* Be conservative about how much space we need before we allow writes.
276 On top of that which is required for deletia, require an extra 2%
277 of the medium to be available, for overhead caused by nodes being
278 split across blocks, etc. */
279
280 size = c->flash_size / 50; /* 2% of flash size */
281 size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */
282 size += c->sector_size - 1; /* ... and round up */
283
284 c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
285
286 /* When do we let the GC thread run in the background */
287
288 c->resv_blocks_gctrigger = c->resv_blocks_write + 1;
289
290 /* When do we allow garbage collection to merge nodes to make
291 long-term progress at the expense of short-term space exhaustion? */
292 c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1;
293
294 /* When do we allow garbage collection to eat from bad blocks rather
295 than actually making progress? */
296 c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2;
297
298 /* What number of 'very dirty' eraseblocks do we allow before we
299 trigger the GC thread even if we don't _need_ the space. When we
300 can't mark nodes obsolete on the medium, the old dirty nodes cause
301 performance problems because we have to inspect and discard them. */
302 c->vdirty_blocks_gctrigger = c->resv_blocks_gctrigger;
303 if (jffs2_can_mark_obsolete(c))
304 c->vdirty_blocks_gctrigger *= 10;
305
306 /* If there's less than this amount of dirty space, don't bother
307 trying to GC to make more space. It'll be a fruitless task */
308 c->nospc_dirty_size = c->sector_size + (c->flash_size / 100);
309
310 dbg_fsbuild("JFFS2 trigger levels (size %d KiB, block size %d KiB, %d blocks)\n",
311 c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks);
312 dbg_fsbuild("Blocks required to allow deletion: %d (%d KiB)\n",
313 c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024);
314 dbg_fsbuild("Blocks required to allow writes: %d (%d KiB)\n",
315 c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024);
316 dbg_fsbuild("Blocks required to quiesce GC thread: %d (%d KiB)\n",
317 c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024);
318 dbg_fsbuild("Blocks required to allow GC merges: %d (%d KiB)\n",
319 c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024);
320 dbg_fsbuild("Blocks required to GC bad blocks: %d (%d KiB)\n",
321 c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024);
322 dbg_fsbuild("Amount of dirty space required to GC: %d bytes\n",
323 c->nospc_dirty_size);
324 dbg_fsbuild("Very dirty blocks before GC triggered: %d\n",
325 c->vdirty_blocks_gctrigger);
326}
327
328int jffs2_do_mount_fs(struct jffs2_sb_info *c)
329{
330 int ret;
331 int i;
332 int size;
333
334 c->free_size = c->flash_size;
335 c->nr_blocks = c->flash_size / c->sector_size;
336 size = sizeof(struct jffs2_eraseblock) * c->nr_blocks;
337#ifndef __ECOS
338 if (jffs2_blocks_use_vmalloc(c))
339 c->blocks = vzalloc(size);
340 else
341#endif
342 c->blocks = kzalloc(size, GFP_KERNEL);
343 if (!c->blocks)
344 return -ENOMEM;
345
346 for (i=0; i<c->nr_blocks; i++) {
347 INIT_LIST_HEAD(&c->blocks[i].list);
348 c->blocks[i].offset = i * c->sector_size;
349 c->blocks[i].free_size = c->sector_size;
350 }
351
352 INIT_LIST_HEAD(&c->clean_list);
353 INIT_LIST_HEAD(&c->very_dirty_list);
354 INIT_LIST_HEAD(&c->dirty_list);
355 INIT_LIST_HEAD(&c->erasable_list);
356 INIT_LIST_HEAD(&c->erasing_list);
357 INIT_LIST_HEAD(&c->erase_checking_list);
358 INIT_LIST_HEAD(&c->erase_pending_list);
359 INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
360 INIT_LIST_HEAD(&c->erase_complete_list);
361 INIT_LIST_HEAD(&c->free_list);
362 INIT_LIST_HEAD(&c->bad_list);
363 INIT_LIST_HEAD(&c->bad_used_list);
364 c->highest_ino = 1;
365 c->summary = NULL;
366
367 ret = jffs2_sum_init(c);
368 if (ret)
369 goto out_free;
370
371 if (jffs2_build_filesystem(c)) {
372 dbg_fsbuild("build_fs failed\n");
373 jffs2_free_ino_caches(c);
374 jffs2_free_raw_node_refs(c);
375 ret = -EIO;
376 goto out_free;
377 }
378
379 jffs2_calc_trigger_levels(c);
380
381 return 0;
382
383 out_free:
384#ifndef __ECOS
385 if (jffs2_blocks_use_vmalloc(c))
386 vfree(c->blocks);
387 else
388#endif
389 kfree(c->blocks);
390
391 return ret;
392}