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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * JFFS2 -- Journalling Flash File System, Version 2. | |
3 | * | |
c00c310e | 4 | * Copyright © 2001-2007 Red Hat, Inc. |
6088c058 | 5 | * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org> |
1da177e4 LT |
6 | * |
7 | * Created by David Woodhouse <dwmw2@infradead.org> | |
8 | * | |
9 | * For licensing information, see the file 'LICENCE' in this directory. | |
10 | * | |
1da177e4 LT |
11 | */ |
12 | ||
5a528957 JP |
13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
14 | ||
1da177e4 LT |
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> | |
1d5cfdb0 | 20 | #include <linux/mm.h> /* kvfree() */ |
1da177e4 LT |
21 | #include "nodelist.h" |
22 | ||
733802d9 AB |
23 | static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *, |
24 | struct jffs2_inode_cache *, struct jffs2_full_dirent **); | |
1da177e4 LT |
25 | |
26 | static inline struct jffs2_inode_cache * | |
27 | first_inode_chain(int *i, struct jffs2_sb_info *c) | |
28 | { | |
65e5a0e1 | 29 | for (; *i < c->inocache_hashsize; (*i)++) { |
1da177e4 LT |
30 | if (c->inocache_list[*i]) |
31 | return c->inocache_list[*i]; | |
32 | } | |
33 | return NULL; | |
34 | } | |
35 | ||
36 | static inline struct jffs2_inode_cache * | |
37 | next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c) | |
38 | { | |
39 | /* More in this chain? */ | |
40 | if (ic->next) | |
41 | return ic->next; | |
42 | (*i)++; | |
43 | return first_inode_chain(i, c); | |
44 | } | |
45 | ||
46 | #define for_each_inode(i, c, ic) \ | |
47 | for (i = 0, ic = first_inode_chain(&i, (c)); \ | |
48 | ic; \ | |
49 | ic = next_inode(&i, ic, (c))) | |
50 | ||
51 | ||
858119e1 | 52 | static void jffs2_build_inode_pass1(struct jffs2_sb_info *c, |
27c72b04 | 53 | struct jffs2_inode_cache *ic) |
1da177e4 LT |
54 | { |
55 | struct jffs2_full_dirent *fd; | |
56 | ||
733802d9 | 57 | dbg_fsbuild("building directory inode #%u\n", ic->ino); |
1da177e4 LT |
58 | |
59 | /* For each child, increase nlink */ | |
60 | for(fd = ic->scan_dents; fd; fd = fd->next) { | |
61 | struct jffs2_inode_cache *child_ic; | |
62 | if (!fd->ino) | |
63 | continue; | |
64 | ||
733802d9 | 65 | /* we can get high latency here with huge directories */ |
1da177e4 LT |
66 | |
67 | child_ic = jffs2_get_ino_cache(c, fd->ino); | |
68 | if (!child_ic) { | |
733802d9 | 69 | dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n", |
1da177e4 LT |
70 | fd->name, fd->ino, ic->ino); |
71 | jffs2_mark_node_obsolete(c, fd->raw); | |
72 | continue; | |
73 | } | |
74 | ||
27c72b04 DW |
75 | if (fd->type == DT_DIR) { |
76 | if (child_ic->pino_nlink) { | |
77 | JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", | |
78 | fd->name, fd->ino, ic->ino); | |
79 | /* TODO: What do we do about it? */ | |
80 | } else { | |
81 | child_ic->pino_nlink = ic->ino; | |
82 | } | |
83 | } else | |
84 | child_ic->pino_nlink++; | |
85 | ||
733802d9 AB |
86 | dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino); |
87 | /* Can't free scan_dents so far. We might need them in pass 2 */ | |
1da177e4 LT |
88 | } |
89 | } | |
90 | ||
91 | /* Scan plan: | |
92 | - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go | |
93 | - Scan directory tree from top down, setting nlink in inocaches | |
94 | - Scan inocaches for inodes with nlink==0 | |
95 | */ | |
96 | static int jffs2_build_filesystem(struct jffs2_sb_info *c) | |
97 | { | |
98 | int ret; | |
99 | int i; | |
100 | struct jffs2_inode_cache *ic; | |
101 | struct jffs2_full_dirent *fd; | |
102 | struct jffs2_full_dirent *dead_fds = NULL; | |
103 | ||
733802d9 AB |
104 | dbg_fsbuild("build FS data structures\n"); |
105 | ||
1da177e4 LT |
106 | /* First, scan the medium and build all the inode caches with |
107 | lists of physical nodes */ | |
108 | ||
31fbdf7a | 109 | c->flags |= JFFS2_SB_FLAG_SCANNING; |
1da177e4 | 110 | ret = jffs2_scan_medium(c); |
31fbdf7a | 111 | c->flags &= ~JFFS2_SB_FLAG_SCANNING; |
1da177e4 LT |
112 | if (ret) |
113 | goto exit; | |
114 | ||
733802d9 | 115 | dbg_fsbuild("scanned flash completely\n"); |
e0c8e42f | 116 | jffs2_dbg_dump_block_lists_nolock(c); |
1da177e4 | 117 | |
733802d9 | 118 | dbg_fsbuild("pass 1 starting\n"); |
31fbdf7a | 119 | c->flags |= JFFS2_SB_FLAG_BUILDING; |
1da177e4 LT |
120 | /* Now scan the directory tree, increasing nlink according to every dirent found. */ |
121 | for_each_inode(i, c, ic) { | |
1da177e4 LT |
122 | if (ic->scan_dents) { |
123 | jffs2_build_inode_pass1(c, ic); | |
124 | cond_resched(); | |
125 | } | |
126 | } | |
1da177e4 | 127 | |
733802d9 | 128 | dbg_fsbuild("pass 1 complete\n"); |
1da177e4 LT |
129 | |
130 | /* Next, scan for inodes with nlink == 0 and remove them. If | |
131 | they were directories, then decrement the nlink of their | |
132 | children too, and repeat the scan. As that's going to be | |
133 | a fairly uncommon occurrence, it's not so evil to do it this | |
134 | way. Recursion bad. */ | |
733802d9 | 135 | dbg_fsbuild("pass 2 starting\n"); |
1da177e4 LT |
136 | |
137 | for_each_inode(i, c, ic) { | |
27c72b04 | 138 | if (ic->pino_nlink) |
1da177e4 | 139 | continue; |
182ec4ee | 140 | |
1da177e4 LT |
141 | jffs2_build_remove_unlinked_inode(c, ic, &dead_fds); |
142 | cond_resched(); | |
182ec4ee | 143 | } |
1da177e4 | 144 | |
733802d9 | 145 | dbg_fsbuild("pass 2a starting\n"); |
1da177e4 LT |
146 | |
147 | while (dead_fds) { | |
148 | fd = dead_fds; | |
149 | dead_fds = fd->next; | |
150 | ||
151 | ic = jffs2_get_ino_cache(c, fd->ino); | |
1da177e4 LT |
152 | |
153 | if (ic) | |
154 | jffs2_build_remove_unlinked_inode(c, ic, &dead_fds); | |
155 | jffs2_free_full_dirent(fd); | |
156 | } | |
157 | ||
733802d9 AB |
158 | dbg_fsbuild("pass 2a complete\n"); |
159 | dbg_fsbuild("freeing temporary data structures\n"); | |
182ec4ee | 160 | |
1da177e4 LT |
161 | /* Finally, we can scan again and free the dirent structs */ |
162 | for_each_inode(i, c, ic) { | |
1da177e4 LT |
163 | while(ic->scan_dents) { |
164 | fd = ic->scan_dents; | |
165 | ic->scan_dents = fd->next; | |
166 | jffs2_free_full_dirent(fd); | |
167 | } | |
168 | ic->scan_dents = NULL; | |
169 | cond_resched(); | |
170 | } | |
aa98d7cf | 171 | jffs2_build_xattr_subsystem(c); |
31fbdf7a | 172 | c->flags &= ~JFFS2_SB_FLAG_BUILDING; |
182ec4ee | 173 | |
733802d9 | 174 | dbg_fsbuild("FS build complete\n"); |
1da177e4 LT |
175 | |
176 | /* Rotate the lists by some number to ensure wear levelling */ | |
177 | jffs2_rotate_lists(c); | |
178 | ||
179 | ret = 0; | |
180 | ||
181 | exit: | |
182 | if (ret) { | |
183 | for_each_inode(i, c, ic) { | |
184 | while(ic->scan_dents) { | |
185 | fd = ic->scan_dents; | |
186 | ic->scan_dents = fd->next; | |
187 | jffs2_free_full_dirent(fd); | |
188 | } | |
189 | } | |
aa98d7cf | 190 | jffs2_clear_xattr_subsystem(c); |
1da177e4 LT |
191 | } |
192 | ||
193 | return ret; | |
194 | } | |
195 | ||
733802d9 AB |
196 | static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, |
197 | struct jffs2_inode_cache *ic, | |
198 | struct jffs2_full_dirent **dead_fds) | |
1da177e4 LT |
199 | { |
200 | struct jffs2_raw_node_ref *raw; | |
201 | struct jffs2_full_dirent *fd; | |
202 | ||
733802d9 | 203 | dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino); |
182ec4ee | 204 | |
1da177e4 LT |
205 | raw = ic->nodes; |
206 | while (raw != (void *)ic) { | |
207 | struct jffs2_raw_node_ref *next = raw->next_in_ino; | |
733802d9 | 208 | dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw)); |
1da177e4 LT |
209 | jffs2_mark_node_obsolete(c, raw); |
210 | raw = next; | |
211 | } | |
212 | ||
213 | if (ic->scan_dents) { | |
214 | int whinged = 0; | |
733802d9 | 215 | dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino); |
1da177e4 LT |
216 | |
217 | while(ic->scan_dents) { | |
218 | struct jffs2_inode_cache *child_ic; | |
219 | ||
220 | fd = ic->scan_dents; | |
221 | ic->scan_dents = fd->next; | |
222 | ||
223 | if (!fd->ino) { | |
224 | /* It's a deletion dirent. Ignore it */ | |
733802d9 | 225 | dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name); |
1da177e4 LT |
226 | jffs2_free_full_dirent(fd); |
227 | continue; | |
228 | } | |
733802d9 | 229 | if (!whinged) |
1da177e4 | 230 | whinged = 1; |
1da177e4 | 231 | |
733802d9 | 232 | dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino); |
182ec4ee | 233 | |
1da177e4 LT |
234 | child_ic = jffs2_get_ino_cache(c, fd->ino); |
235 | if (!child_ic) { | |
733802d9 AB |
236 | dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n", |
237 | fd->name, fd->ino); | |
1da177e4 LT |
238 | jffs2_free_full_dirent(fd); |
239 | continue; | |
240 | } | |
241 | ||
182ec4ee | 242 | /* Reduce nlink of the child. If it's now zero, stick it on the |
1da177e4 LT |
243 | dead_fds list to be cleaned up later. Else just free the fd */ |
244 | ||
27c72b04 DW |
245 | if (fd->type == DT_DIR) |
246 | child_ic->pino_nlink = 0; | |
247 | else | |
248 | child_ic->pino_nlink--; | |
182ec4ee | 249 | |
27c72b04 DW |
250 | if (!child_ic->pino_nlink) { |
251 | dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n", | |
733802d9 | 252 | fd->ino, fd->name); |
1da177e4 LT |
253 | fd->next = *dead_fds; |
254 | *dead_fds = fd; | |
255 | } else { | |
733802d9 | 256 | dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n", |
27c72b04 | 257 | fd->ino, fd->name, child_ic->pino_nlink); |
1da177e4 LT |
258 | jffs2_free_full_dirent(fd); |
259 | } | |
260 | } | |
261 | } | |
262 | ||
263 | /* | |
182ec4ee | 264 | We don't delete the inocache from the hash list and free it yet. |
1da177e4 LT |
265 | The erase code will do that, when all the nodes are completely gone. |
266 | */ | |
267 | } | |
268 | ||
269 | static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c) | |
270 | { | |
271 | uint32_t size; | |
272 | ||
273 | /* Deletion should almost _always_ be allowed. We're fairly | |
274 | buggered once we stop allowing people to delete stuff | |
275 | because there's not enough free space... */ | |
276 | c->resv_blocks_deletion = 2; | |
277 | ||
182ec4ee | 278 | /* Be conservative about how much space we need before we allow writes. |
1da177e4 LT |
279 | On top of that which is required for deletia, require an extra 2% |
280 | of the medium to be available, for overhead caused by nodes being | |
281 | split across blocks, etc. */ | |
282 | ||
283 | size = c->flash_size / 50; /* 2% of flash size */ | |
284 | size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */ | |
285 | size += c->sector_size - 1; /* ... and round up */ | |
286 | ||
287 | c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size); | |
288 | ||
289 | /* When do we let the GC thread run in the background */ | |
290 | ||
291 | c->resv_blocks_gctrigger = c->resv_blocks_write + 1; | |
292 | ||
182ec4ee | 293 | /* When do we allow garbage collection to merge nodes to make |
1da177e4 LT |
294 | long-term progress at the expense of short-term space exhaustion? */ |
295 | c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1; | |
296 | ||
297 | /* When do we allow garbage collection to eat from bad blocks rather | |
298 | than actually making progress? */ | |
299 | c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2; | |
300 | ||
8fb870df DW |
301 | /* What number of 'very dirty' eraseblocks do we allow before we |
302 | trigger the GC thread even if we don't _need_ the space. When we | |
303 | can't mark nodes obsolete on the medium, the old dirty nodes cause | |
304 | performance problems because we have to inspect and discard them. */ | |
85becc53 | 305 | c->vdirty_blocks_gctrigger = c->resv_blocks_gctrigger; |
8fb870df DW |
306 | if (jffs2_can_mark_obsolete(c)) |
307 | c->vdirty_blocks_gctrigger *= 10; | |
308 | ||
1da177e4 LT |
309 | /* If there's less than this amount of dirty space, don't bother |
310 | trying to GC to make more space. It'll be a fruitless task */ | |
311 | c->nospc_dirty_size = c->sector_size + (c->flash_size / 100); | |
312 | ||
5a528957 JP |
313 | dbg_fsbuild("trigger levels (size %d KiB, block size %d KiB, %d blocks)\n", |
314 | c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks); | |
733802d9 AB |
315 | dbg_fsbuild("Blocks required to allow deletion: %d (%d KiB)\n", |
316 | c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024); | |
317 | dbg_fsbuild("Blocks required to allow writes: %d (%d KiB)\n", | |
318 | c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024); | |
319 | dbg_fsbuild("Blocks required to quiesce GC thread: %d (%d KiB)\n", | |
320 | c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024); | |
321 | dbg_fsbuild("Blocks required to allow GC merges: %d (%d KiB)\n", | |
322 | c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024); | |
323 | dbg_fsbuild("Blocks required to GC bad blocks: %d (%d KiB)\n", | |
324 | c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024); | |
325 | dbg_fsbuild("Amount of dirty space required to GC: %d bytes\n", | |
326 | c->nospc_dirty_size); | |
8fb870df DW |
327 | dbg_fsbuild("Very dirty blocks before GC triggered: %d\n", |
328 | c->vdirty_blocks_gctrigger); | |
182ec4ee | 329 | } |
1da177e4 LT |
330 | |
331 | int jffs2_do_mount_fs(struct jffs2_sb_info *c) | |
332 | { | |
c617e842 | 333 | int ret; |
1da177e4 | 334 | int i; |
d55849aa | 335 | int size; |
1da177e4 LT |
336 | |
337 | c->free_size = c->flash_size; | |
338 | c->nr_blocks = c->flash_size / c->sector_size; | |
d55849aa | 339 | size = sizeof(struct jffs2_eraseblock) * c->nr_blocks; |
737b7661 | 340 | #ifndef __ECOS |
4ce1f562 | 341 | if (jffs2_blocks_use_vmalloc(c)) |
7ddbead6 | 342 | c->blocks = vzalloc(size); |
1da177e4 | 343 | else |
737b7661 | 344 | #endif |
7ddbead6 | 345 | c->blocks = kzalloc(size, GFP_KERNEL); |
1da177e4 LT |
346 | if (!c->blocks) |
347 | return -ENOMEM; | |
d55849aa | 348 | |
1da177e4 LT |
349 | for (i=0; i<c->nr_blocks; i++) { |
350 | INIT_LIST_HEAD(&c->blocks[i].list); | |
351 | c->blocks[i].offset = i * c->sector_size; | |
352 | c->blocks[i].free_size = c->sector_size; | |
1da177e4 LT |
353 | } |
354 | ||
1da177e4 LT |
355 | INIT_LIST_HEAD(&c->clean_list); |
356 | INIT_LIST_HEAD(&c->very_dirty_list); | |
357 | INIT_LIST_HEAD(&c->dirty_list); | |
358 | INIT_LIST_HEAD(&c->erasable_list); | |
359 | INIT_LIST_HEAD(&c->erasing_list); | |
e2bc322b | 360 | INIT_LIST_HEAD(&c->erase_checking_list); |
1da177e4 LT |
361 | INIT_LIST_HEAD(&c->erase_pending_list); |
362 | INIT_LIST_HEAD(&c->erasable_pending_wbuf_list); | |
363 | INIT_LIST_HEAD(&c->erase_complete_list); | |
364 | INIT_LIST_HEAD(&c->free_list); | |
365 | INIT_LIST_HEAD(&c->bad_list); | |
366 | INIT_LIST_HEAD(&c->bad_used_list); | |
367 | c->highest_ino = 1; | |
e631ddba FH |
368 | c->summary = NULL; |
369 | ||
c617e842 FH |
370 | ret = jffs2_sum_init(c); |
371 | if (ret) | |
cfa72397 | 372 | goto out_free; |
1da177e4 LT |
373 | |
374 | if (jffs2_build_filesystem(c)) { | |
733802d9 | 375 | dbg_fsbuild("build_fs failed\n"); |
1da177e4 LT |
376 | jffs2_free_ino_caches(c); |
377 | jffs2_free_raw_node_refs(c); | |
cfa72397 DA |
378 | ret = -EIO; |
379 | goto out_free; | |
1da177e4 LT |
380 | } |
381 | ||
382 | jffs2_calc_trigger_levels(c); | |
383 | ||
384 | return 0; | |
cfa72397 DA |
385 | |
386 | out_free: | |
1d5cfdb0 | 387 | kvfree(c->blocks); |
cfa72397 DA |
388 | |
389 | return ret; | |
1da177e4 | 390 | } |