blob: 02826967ab58918ac6fa6ec7723d5e81485c357e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright (C) 2001-2003 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
Thomas Gleixner182ec4e2005-11-07 11:16:07 +000010 * $Id: build.c,v 1.85 2005/11/07 11:14:38 gleixner Exp $
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 *
12 */
13
14#include <linux/kernel.h>
15#include <linux/sched.h>
16#include <linux/slab.h>
17#include <linux/vmalloc.h>
18#include <linux/mtd/mtd.h>
19#include "nodelist.h"
20
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010021static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *,
22 struct jffs2_inode_cache *, struct jffs2_full_dirent **);
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
24static inline struct jffs2_inode_cache *
25first_inode_chain(int *i, struct jffs2_sb_info *c)
26{
27 for (; *i < INOCACHE_HASHSIZE; (*i)++) {
28 if (c->inocache_list[*i])
29 return c->inocache_list[*i];
30 }
31 return NULL;
32}
33
34static inline struct jffs2_inode_cache *
35next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c)
36{
37 /* More in this chain? */
38 if (ic->next)
39 return ic->next;
40 (*i)++;
41 return first_inode_chain(i, c);
42}
43
44#define for_each_inode(i, c, ic) \
45 for (i = 0, ic = first_inode_chain(&i, (c)); \
46 ic; \
47 ic = next_inode(&i, ic, (c)))
48
49
Arjan van de Ven858119e2006-01-14 13:20:43 -080050static void jffs2_build_inode_pass1(struct jffs2_sb_info *c,
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010051 struct jffs2_inode_cache *ic)
Linus Torvalds1da177e2005-04-16 15:20:36 -070052{
53 struct jffs2_full_dirent *fd;
54
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010055 dbg_fsbuild("building directory inode #%u\n", ic->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57 /* For each child, increase nlink */
58 for(fd = ic->scan_dents; fd; fd = fd->next) {
59 struct jffs2_inode_cache *child_ic;
60 if (!fd->ino)
61 continue;
62
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010063 /* we can get high latency here with huge directories */
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65 child_ic = jffs2_get_ino_cache(c, fd->ino);
66 if (!child_ic) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010067 dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 fd->name, fd->ino, ic->ino);
69 jffs2_mark_node_obsolete(c, fd->raw);
70 continue;
71 }
72
73 if (child_ic->nlink++ && fd->type == DT_DIR) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010074 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? */
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 }
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010078 dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino);
79 /* Can't free scan_dents so far. We might need them in pass 2 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 }
81}
82
83/* Scan plan:
84 - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go
85 - Scan directory tree from top down, setting nlink in inocaches
86 - Scan inocaches for inodes with nlink==0
87*/
88static int jffs2_build_filesystem(struct jffs2_sb_info *c)
89{
90 int ret;
91 int i;
92 struct jffs2_inode_cache *ic;
93 struct jffs2_full_dirent *fd;
94 struct jffs2_full_dirent *dead_fds = NULL;
95
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010096 dbg_fsbuild("build FS data structures\n");
97
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 /* First, scan the medium and build all the inode caches with
99 lists of physical nodes */
100
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000101 c->flags |= JFFS2_SB_FLAG_SCANNING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 ret = jffs2_scan_medium(c);
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000103 c->flags &= ~JFFS2_SB_FLAG_SCANNING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 if (ret)
105 goto exit;
106
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100107 dbg_fsbuild("scanned flash completely\n");
Artem B. Bityutskiye0c8e422005-07-24 16:14:17 +0100108 jffs2_dbg_dump_block_lists_nolock(c);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100110 dbg_fsbuild("pass 1 starting\n");
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000111 c->flags |= JFFS2_SB_FLAG_BUILDING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 /* Now scan the directory tree, increasing nlink according to every dirent found. */
113 for_each_inode(i, c, ic) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 if (ic->scan_dents) {
115 jffs2_build_inode_pass1(c, ic);
116 cond_resched();
117 }
118 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100120 dbg_fsbuild("pass 1 complete\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
122 /* Next, scan for inodes with nlink == 0 and remove them. If
123 they were directories, then decrement the nlink of their
124 children too, and repeat the scan. As that's going to be
125 a fairly uncommon occurrence, it's not so evil to do it this
126 way. Recursion bad. */
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100127 dbg_fsbuild("pass 2 starting\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
129 for_each_inode(i, c, ic) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 if (ic->nlink)
131 continue;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000132
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
134 cond_resched();
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000135 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100137 dbg_fsbuild("pass 2a starting\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138
139 while (dead_fds) {
140 fd = dead_fds;
141 dead_fds = fd->next;
142
143 ic = jffs2_get_ino_cache(c, fd->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
145 if (ic)
146 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
147 jffs2_free_full_dirent(fd);
148 }
149
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100150 dbg_fsbuild("pass 2a complete\n");
151 dbg_fsbuild("freeing temporary data structures\n");
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 /* Finally, we can scan again and free the dirent structs */
154 for_each_inode(i, c, ic) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 while(ic->scan_dents) {
156 fd = ic->scan_dents;
157 ic->scan_dents = fd->next;
158 jffs2_free_full_dirent(fd);
159 }
160 ic->scan_dents = NULL;
161 cond_resched();
162 }
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900163 jffs2_build_xattr_subsystem(c);
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000164 c->flags &= ~JFFS2_SB_FLAG_BUILDING;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000165
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100166 dbg_fsbuild("FS build complete\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
168 /* Rotate the lists by some number to ensure wear levelling */
169 jffs2_rotate_lists(c);
170
171 ret = 0;
172
173exit:
174 if (ret) {
175 for_each_inode(i, c, ic) {
176 while(ic->scan_dents) {
177 fd = ic->scan_dents;
178 ic->scan_dents = fd->next;
179 jffs2_free_full_dirent(fd);
180 }
181 }
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900182 jffs2_clear_xattr_subsystem(c);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 }
184
185 return ret;
186}
187
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100188static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c,
189 struct jffs2_inode_cache *ic,
190 struct jffs2_full_dirent **dead_fds)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191{
192 struct jffs2_raw_node_ref *raw;
193 struct jffs2_full_dirent *fd;
194
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100195 dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000196
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 raw = ic->nodes;
198 while (raw != (void *)ic) {
199 struct jffs2_raw_node_ref *next = raw->next_in_ino;
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100200 dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 jffs2_mark_node_obsolete(c, raw);
202 raw = next;
203 }
204
205 if (ic->scan_dents) {
206 int whinged = 0;
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100207 dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
209 while(ic->scan_dents) {
210 struct jffs2_inode_cache *child_ic;
211
212 fd = ic->scan_dents;
213 ic->scan_dents = fd->next;
214
215 if (!fd->ino) {
216 /* It's a deletion dirent. Ignore it */
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100217 dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 jffs2_free_full_dirent(fd);
219 continue;
220 }
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100221 if (!whinged)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 whinged = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100224 dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000225
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 child_ic = jffs2_get_ino_cache(c, fd->ino);
227 if (!child_ic) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100228 dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n",
229 fd->name, fd->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 jffs2_free_full_dirent(fd);
231 continue;
232 }
233
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000234 /* Reduce nlink of the child. If it's now zero, stick it on the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 dead_fds list to be cleaned up later. Else just free the fd */
236
237 child_ic->nlink--;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000238
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 if (!child_ic->nlink) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100240 dbg_fsbuild("inode #%u (\"%s\") has now got zero nlink, adding to dead_fds list.\n",
241 fd->ino, fd->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 fd->next = *dead_fds;
243 *dead_fds = fd;
244 } else {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100245 dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
246 fd->ino, fd->name, child_ic->nlink);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 jffs2_free_full_dirent(fd);
248 }
249 }
250 }
251
252 /*
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000253 We don't delete the inocache from the hash list and free it yet.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 The erase code will do that, when all the nodes are completely gone.
255 */
256}
257
258static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c)
259{
260 uint32_t size;
261
262 /* Deletion should almost _always_ be allowed. We're fairly
263 buggered once we stop allowing people to delete stuff
264 because there's not enough free space... */
265 c->resv_blocks_deletion = 2;
266
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000267 /* Be conservative about how much space we need before we allow writes.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 On top of that which is required for deletia, require an extra 2%
269 of the medium to be available, for overhead caused by nodes being
270 split across blocks, etc. */
271
272 size = c->flash_size / 50; /* 2% of flash size */
273 size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */
274 size += c->sector_size - 1; /* ... and round up */
275
276 c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
277
278 /* When do we let the GC thread run in the background */
279
280 c->resv_blocks_gctrigger = c->resv_blocks_write + 1;
281
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000282 /* When do we allow garbage collection to merge nodes to make
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 long-term progress at the expense of short-term space exhaustion? */
284 c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1;
285
286 /* When do we allow garbage collection to eat from bad blocks rather
287 than actually making progress? */
288 c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2;
289
290 /* If there's less than this amount of dirty space, don't bother
291 trying to GC to make more space. It'll be a fruitless task */
292 c->nospc_dirty_size = c->sector_size + (c->flash_size / 100);
293
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100294 dbg_fsbuild("JFFS2 trigger levels (size %d KiB, block size %d KiB, %d blocks)\n",
295 c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks);
296 dbg_fsbuild("Blocks required to allow deletion: %d (%d KiB)\n",
297 c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024);
298 dbg_fsbuild("Blocks required to allow writes: %d (%d KiB)\n",
299 c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024);
300 dbg_fsbuild("Blocks required to quiesce GC thread: %d (%d KiB)\n",
301 c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024);
302 dbg_fsbuild("Blocks required to allow GC merges: %d (%d KiB)\n",
303 c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024);
304 dbg_fsbuild("Blocks required to GC bad blocks: %d (%d KiB)\n",
305 c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024);
306 dbg_fsbuild("Amount of dirty space required to GC: %d bytes\n",
307 c->nospc_dirty_size);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000308}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
310int jffs2_do_mount_fs(struct jffs2_sb_info *c)
311{
Ferenc Havasic617e842005-09-07 12:22:01 +0100312 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 int i;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100314 int size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315
316 c->free_size = c->flash_size;
317 c->nr_blocks = c->flash_size / c->sector_size;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100318 size = sizeof(struct jffs2_eraseblock) * c->nr_blocks;
Andrew Lunn737b7662005-07-30 16:29:30 +0100319#ifndef __ECOS
Ferenc Havasi4ce1f562005-08-31 14:51:04 +0100320 if (jffs2_blocks_use_vmalloc(c))
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100321 c->blocks = vmalloc(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 else
Andrew Lunn737b7662005-07-30 16:29:30 +0100323#endif
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100324 c->blocks = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 if (!c->blocks)
326 return -ENOMEM;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100327
328 memset(c->blocks, 0, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 for (i=0; i<c->nr_blocks; i++) {
330 INIT_LIST_HEAD(&c->blocks[i].list);
331 c->blocks[i].offset = i * c->sector_size;
332 c->blocks[i].free_size = c->sector_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 }
334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 INIT_LIST_HEAD(&c->clean_list);
336 INIT_LIST_HEAD(&c->very_dirty_list);
337 INIT_LIST_HEAD(&c->dirty_list);
338 INIT_LIST_HEAD(&c->erasable_list);
339 INIT_LIST_HEAD(&c->erasing_list);
340 INIT_LIST_HEAD(&c->erase_pending_list);
341 INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
342 INIT_LIST_HEAD(&c->erase_complete_list);
343 INIT_LIST_HEAD(&c->free_list);
344 INIT_LIST_HEAD(&c->bad_list);
345 INIT_LIST_HEAD(&c->bad_used_list);
346 c->highest_ino = 1;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100347 c->summary = NULL;
348
Ferenc Havasic617e842005-09-07 12:22:01 +0100349 ret = jffs2_sum_init(c);
350 if (ret)
351 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
353 if (jffs2_build_filesystem(c)) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100354 dbg_fsbuild("build_fs failed\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 jffs2_free_ino_caches(c);
356 jffs2_free_raw_node_refs(c);
Andrew Lunn737b7662005-07-30 16:29:30 +0100357#ifndef __ECOS
Ferenc Havasi4ce1f562005-08-31 14:51:04 +0100358 if (jffs2_blocks_use_vmalloc(c))
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100359 vfree(c->blocks);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000360 else
Andrew Lunn737b7662005-07-30 16:29:30 +0100361#endif
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100362 kfree(c->blocks);
363
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 return -EIO;
365 }
366
367 jffs2_calc_trigger_levels(c);
368
369 return 0;
370}