blob: 85c6be2db02f7fc5c9b0152cc723ec39e6c25584 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
David Woodhousec00c3102007-04-25 14:16:47 +01004 * Copyright © 2001-2007 Red Hat, Inc.
David Woodhouse6088c052010-08-08 14:15:22 +01005 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 */
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
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010020static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *,
21 struct jffs2_inode_cache *, struct jffs2_full_dirent **);
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
23static inline struct jffs2_inode_cache *
24first_inode_chain(int *i, struct jffs2_sb_info *c)
25{
Daniel Drake65e5a0e2010-10-07 19:14:02 +010026 for (; *i < c->inocache_hashsize; (*i)++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 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
Arjan van de Ven858119e2006-01-14 13:20:43 -080049static void jffs2_build_inode_pass1(struct jffs2_sb_info *c,
David Woodhouse27c72b02008-05-01 18:47:17 +010050 struct jffs2_inode_cache *ic)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
52 struct jffs2_full_dirent *fd;
53
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010054 dbg_fsbuild("building directory inode #%u\n", ic->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
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
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010062 /* we can get high latency here with huge directories */
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
64 child_ic = jffs2_get_ino_cache(c, fd->ino);
65 if (!child_ic) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010066 dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 fd->name, fd->ino, ic->ino);
68 jffs2_mark_node_obsolete(c, fd->raw);
69 continue;
70 }
71
David Woodhouse27c72b02008-05-01 18:47:17 +010072 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
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +010083 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 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 }
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
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100101 dbg_fsbuild("build FS data structures\n");
102
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 /* First, scan the medium and build all the inode caches with
104 lists of physical nodes */
105
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000106 c->flags |= JFFS2_SB_FLAG_SCANNING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 ret = jffs2_scan_medium(c);
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000108 c->flags &= ~JFFS2_SB_FLAG_SCANNING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 if (ret)
110 goto exit;
111
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100112 dbg_fsbuild("scanned flash completely\n");
Artem B. Bityutskiye0c8e422005-07-24 16:14:17 +0100113 jffs2_dbg_dump_block_lists_nolock(c);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100115 dbg_fsbuild("pass 1 starting\n");
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000116 c->flags |= JFFS2_SB_FLAG_BUILDING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 /* Now scan the directory tree, increasing nlink according to every dirent found. */
118 for_each_inode(i, c, ic) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 if (ic->scan_dents) {
120 jffs2_build_inode_pass1(c, ic);
121 cond_resched();
122 }
123 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100125 dbg_fsbuild("pass 1 complete\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126
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. */
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100132 dbg_fsbuild("pass 2 starting\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
134 for_each_inode(i, c, ic) {
David Woodhouse27c72b02008-05-01 18:47:17 +0100135 if (ic->pino_nlink)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 continue;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000137
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
139 cond_resched();
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000140 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100142 dbg_fsbuild("pass 2a starting\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
144 while (dead_fds) {
145 fd = dead_fds;
146 dead_fds = fd->next;
147
148 ic = jffs2_get_ino_cache(c, fd->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
150 if (ic)
151 jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
152 jffs2_free_full_dirent(fd);
153 }
154
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100155 dbg_fsbuild("pass 2a complete\n");
156 dbg_fsbuild("freeing temporary data structures\n");
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000157
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 /* Finally, we can scan again and free the dirent structs */
159 for_each_inode(i, c, ic) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 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 }
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900168 jffs2_build_xattr_subsystem(c);
Artem B. Bityuckiy31fbdf72005-02-28 08:21:09 +0000169 c->flags &= ~JFFS2_SB_FLAG_BUILDING;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000170
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100171 dbg_fsbuild("FS build complete\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
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 }
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +0900187 jffs2_clear_xattr_subsystem(c);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 }
189
190 return ret;
191}
192
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100193static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c,
194 struct jffs2_inode_cache *ic,
195 struct jffs2_full_dirent **dead_fds)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196{
197 struct jffs2_raw_node_ref *raw;
198 struct jffs2_full_dirent *fd;
199
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100200 dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000201
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 raw = ic->nodes;
203 while (raw != (void *)ic) {
204 struct jffs2_raw_node_ref *next = raw->next_in_ino;
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100205 dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 jffs2_mark_node_obsolete(c, raw);
207 raw = next;
208 }
209
210 if (ic->scan_dents) {
211 int whinged = 0;
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100212 dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
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 */
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100222 dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 jffs2_free_full_dirent(fd);
224 continue;
225 }
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100226 if (!whinged)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 whinged = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100229 dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000230
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 child_ic = jffs2_get_ino_cache(c, fd->ino);
232 if (!child_ic) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100233 dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n",
234 fd->name, fd->ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 jffs2_free_full_dirent(fd);
236 continue;
237 }
238
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000239 /* Reduce nlink of the child. If it's now zero, stick it on the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 dead_fds list to be cleaned up later. Else just free the fd */
241
David Woodhouse27c72b02008-05-01 18:47:17 +0100242 if (fd->type == DT_DIR)
243 child_ic->pino_nlink = 0;
244 else
245 child_ic->pino_nlink--;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000246
David Woodhouse27c72b02008-05-01 18:47:17 +0100247 if (!child_ic->pino_nlink) {
248 dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n",
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100249 fd->ino, fd->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 fd->next = *dead_fds;
251 *dead_fds = fd;
252 } else {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100253 dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
David Woodhouse27c72b02008-05-01 18:47:17 +0100254 fd->ino, fd->name, child_ic->pino_nlink);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 jffs2_free_full_dirent(fd);
256 }
257 }
258 }
259
260 /*
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000261 We don't delete the inocache from the hash list and free it yet.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 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
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000275 /* Be conservative about how much space we need before we allow writes.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 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
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000290 /* When do we allow garbage collection to merge nodes to make
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 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
David Woodhouse8fb870df2007-10-06 15:12:58 -0400298 /* 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. */
David Woodhouse85becc52007-10-13 11:29:07 +0100302 c->vdirty_blocks_gctrigger = c->resv_blocks_gctrigger;
David Woodhouse8fb870df2007-10-06 15:12:58 -0400303 if (jffs2_can_mark_obsolete(c))
304 c->vdirty_blocks_gctrigger *= 10;
305
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 /* 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
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100310 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);
David Woodhouse8fb870df2007-10-06 15:12:58 -0400324 dbg_fsbuild("Very dirty blocks before GC triggered: %d\n",
325 c->vdirty_blocks_gctrigger);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000326}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327
328int jffs2_do_mount_fs(struct jffs2_sb_info *c)
329{
Ferenc Havasic617e842005-09-07 12:22:01 +0100330 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 int i;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100332 int size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
334 c->free_size = c->flash_size;
335 c->nr_blocks = c->flash_size / c->sector_size;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100336 size = sizeof(struct jffs2_eraseblock) * c->nr_blocks;
Andrew Lunn737b7662005-07-30 16:29:30 +0100337#ifndef __ECOS
Ferenc Havasi4ce1f562005-08-31 14:51:04 +0100338 if (jffs2_blocks_use_vmalloc(c))
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100339 c->blocks = vmalloc(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 else
Andrew Lunn737b7662005-07-30 16:29:30 +0100341#endif
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100342 c->blocks = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 if (!c->blocks)
344 return -ENOMEM;
Artem B. Bityutskiyd55849a2005-09-27 14:40:52 +0100345
346 memset(c->blocks, 0, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 for (i=0; i<c->nr_blocks; i++) {
348 INIT_LIST_HEAD(&c->blocks[i].list);
349 c->blocks[i].offset = i * c->sector_size;
350 c->blocks[i].free_size = c->sector_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 }
352
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 INIT_LIST_HEAD(&c->clean_list);
354 INIT_LIST_HEAD(&c->very_dirty_list);
355 INIT_LIST_HEAD(&c->dirty_list);
356 INIT_LIST_HEAD(&c->erasable_list);
357 INIT_LIST_HEAD(&c->erasing_list);
David Woodhousee2bc3222008-04-23 14:15:24 +0100358 INIT_LIST_HEAD(&c->erase_checking_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 INIT_LIST_HEAD(&c->erase_pending_list);
360 INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
361 INIT_LIST_HEAD(&c->erase_complete_list);
362 INIT_LIST_HEAD(&c->free_list);
363 INIT_LIST_HEAD(&c->bad_list);
364 INIT_LIST_HEAD(&c->bad_used_list);
365 c->highest_ino = 1;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100366 c->summary = NULL;
367
Ferenc Havasic617e842005-09-07 12:22:01 +0100368 ret = jffs2_sum_init(c);
369 if (ret)
Dmitry Adamushkocfa72392007-01-19 01:20:30 +0100370 goto out_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371
372 if (jffs2_build_filesystem(c)) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100373 dbg_fsbuild("build_fs failed\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 jffs2_free_ino_caches(c);
375 jffs2_free_raw_node_refs(c);
Dmitry Adamushkocfa72392007-01-19 01:20:30 +0100376 ret = -EIO;
377 goto out_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 }
379
380 jffs2_calc_trigger_levels(c);
381
382 return 0;
Dmitry Adamushkocfa72392007-01-19 01:20:30 +0100383
384 out_free:
385#ifndef __ECOS
386 if (jffs2_blocks_use_vmalloc(c))
387 vfree(c->blocks);
388 else
389#endif
390 kfree(c->blocks);
391
392 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393}