Commit | Line | Data |
---|---|---|
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> | |
20 | #include "nodelist.h" | |
21 | ||
733802d9 AB |
22 | static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *, |
23 | struct jffs2_inode_cache *, struct jffs2_full_dirent **); | |
1da177e4 LT |
24 | |
25 | static inline struct jffs2_inode_cache * | |
26 | first_inode_chain(int *i, struct jffs2_sb_info *c) | |
27 | { | |
65e5a0e1 | 28 | for (; *i < c->inocache_hashsize; (*i)++) { |
1da177e4 LT |
29 | if (c->inocache_list[*i]) |
30 | return c->inocache_list[*i]; | |
31 | } | |
32 | return NULL; | |
33 | } | |
34 | ||
35 | static inline struct jffs2_inode_cache * | |
36 | next_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 | ||
858119e1 | 51 | static void jffs2_build_inode_pass1(struct jffs2_sb_info *c, |
27c72b04 | 52 | struct jffs2_inode_cache *ic) |
1da177e4 LT |
53 | { |
54 | struct jffs2_full_dirent *fd; | |
55 | ||
733802d9 | 56 | dbg_fsbuild("building directory inode #%u\n", ic->ino); |
1da177e4 LT |
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 | ||
733802d9 | 64 | /* we can get high latency here with huge directories */ |
1da177e4 LT |
65 | |
66 | child_ic = jffs2_get_ino_cache(c, fd->ino); | |
67 | if (!child_ic) { | |
733802d9 | 68 | dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n", |
1da177e4 LT |
69 | fd->name, fd->ino, ic->ino); |
70 | jffs2_mark_node_obsolete(c, fd->raw); | |
71 | continue; | |
72 | } | |
73 | ||
27c72b04 DW |
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 | ||
733802d9 AB |
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 */ | |
1da177e4 LT |
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 | */ | |
95 | static 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 | ||
733802d9 AB |
103 | dbg_fsbuild("build FS data structures\n"); |
104 | ||
1da177e4 LT |
105 | /* First, scan the medium and build all the inode caches with |
106 | lists of physical nodes */ | |
107 | ||
31fbdf7a | 108 | c->flags |= JFFS2_SB_FLAG_SCANNING; |
1da177e4 | 109 | ret = jffs2_scan_medium(c); |
31fbdf7a | 110 | c->flags &= ~JFFS2_SB_FLAG_SCANNING; |
1da177e4 LT |
111 | if (ret) |
112 | goto exit; | |
113 | ||
733802d9 | 114 | dbg_fsbuild("scanned flash completely\n"); |
e0c8e42f | 115 | jffs2_dbg_dump_block_lists_nolock(c); |
1da177e4 | 116 | |
733802d9 | 117 | dbg_fsbuild("pass 1 starting\n"); |
31fbdf7a | 118 | c->flags |= JFFS2_SB_FLAG_BUILDING; |
1da177e4 LT |
119 | /* Now scan the directory tree, increasing nlink according to every dirent found. */ |
120 | for_each_inode(i, c, ic) { | |
1da177e4 LT |
121 | if (ic->scan_dents) { |
122 | jffs2_build_inode_pass1(c, ic); | |
123 | cond_resched(); | |
124 | } | |
125 | } | |
1da177e4 | 126 | |
733802d9 | 127 | dbg_fsbuild("pass 1 complete\n"); |
1da177e4 LT |
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. */ | |
733802d9 | 134 | dbg_fsbuild("pass 2 starting\n"); |
1da177e4 LT |
135 | |
136 | for_each_inode(i, c, ic) { | |
27c72b04 | 137 | if (ic->pino_nlink) |
1da177e4 | 138 | continue; |
182ec4ee | 139 | |
1da177e4 LT |
140 | jffs2_build_remove_unlinked_inode(c, ic, &dead_fds); |
141 | cond_resched(); | |
182ec4ee | 142 | } |
1da177e4 | 143 | |
733802d9 | 144 | dbg_fsbuild("pass 2a starting\n"); |
1da177e4 LT |
145 | |
146 | while (dead_fds) { | |
147 | fd = dead_fds; | |
148 | dead_fds = fd->next; | |
149 | ||
150 | ic = jffs2_get_ino_cache(c, fd->ino); | |
1da177e4 LT |
151 | |
152 | if (ic) | |
153 | jffs2_build_remove_unlinked_inode(c, ic, &dead_fds); | |
154 | jffs2_free_full_dirent(fd); | |
155 | } | |
156 | ||
733802d9 AB |
157 | dbg_fsbuild("pass 2a complete\n"); |
158 | dbg_fsbuild("freeing temporary data structures\n"); | |
182ec4ee | 159 | |
1da177e4 LT |
160 | /* Finally, we can scan again and free the dirent structs */ |
161 | for_each_inode(i, c, ic) { | |
1da177e4 LT |
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 | } | |
aa98d7cf | 170 | jffs2_build_xattr_subsystem(c); |
31fbdf7a | 171 | c->flags &= ~JFFS2_SB_FLAG_BUILDING; |
182ec4ee | 172 | |
733802d9 | 173 | dbg_fsbuild("FS build complete\n"); |
1da177e4 LT |
174 | |
175 | /* Rotate the lists by some number to ensure wear levelling */ | |
176 | jffs2_rotate_lists(c); | |
177 | ||
178 | ret = 0; | |
179 | ||
180 | exit: | |
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 | } | |
aa98d7cf | 189 | jffs2_clear_xattr_subsystem(c); |
1da177e4 LT |
190 | } |
191 | ||
192 | return ret; | |
193 | } | |
194 | ||
733802d9 AB |
195 | static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, |
196 | struct jffs2_inode_cache *ic, | |
197 | struct jffs2_full_dirent **dead_fds) | |
1da177e4 LT |
198 | { |
199 | struct jffs2_raw_node_ref *raw; | |
200 | struct jffs2_full_dirent *fd; | |
201 | ||
733802d9 | 202 | dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino); |
182ec4ee | 203 | |
1da177e4 LT |
204 | raw = ic->nodes; |
205 | while (raw != (void *)ic) { | |
206 | struct jffs2_raw_node_ref *next = raw->next_in_ino; | |
733802d9 | 207 | dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw)); |
1da177e4 LT |
208 | jffs2_mark_node_obsolete(c, raw); |
209 | raw = next; | |
210 | } | |
211 | ||
212 | if (ic->scan_dents) { | |
213 | int whinged = 0; | |
733802d9 | 214 | dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino); |
1da177e4 LT |
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 */ | |
733802d9 | 224 | dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name); |
1da177e4 LT |
225 | jffs2_free_full_dirent(fd); |
226 | continue; | |
227 | } | |
733802d9 | 228 | if (!whinged) |
1da177e4 | 229 | whinged = 1; |
1da177e4 | 230 | |
733802d9 | 231 | dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino); |
182ec4ee | 232 | |
1da177e4 LT |
233 | child_ic = jffs2_get_ino_cache(c, fd->ino); |
234 | if (!child_ic) { | |
733802d9 AB |
235 | dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n", |
236 | fd->name, fd->ino); | |
1da177e4 LT |
237 | jffs2_free_full_dirent(fd); |
238 | continue; | |
239 | } | |
240 | ||
182ec4ee | 241 | /* Reduce nlink of the child. If it's now zero, stick it on the |
1da177e4 LT |
242 | dead_fds list to be cleaned up later. Else just free the fd */ |
243 | ||
27c72b04 DW |
244 | if (fd->type == DT_DIR) |
245 | child_ic->pino_nlink = 0; | |
246 | else | |
247 | child_ic->pino_nlink--; | |
182ec4ee | 248 | |
27c72b04 DW |
249 | if (!child_ic->pino_nlink) { |
250 | dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n", | |
733802d9 | 251 | fd->ino, fd->name); |
1da177e4 LT |
252 | fd->next = *dead_fds; |
253 | *dead_fds = fd; | |
254 | } else { | |
733802d9 | 255 | dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n", |
27c72b04 | 256 | fd->ino, fd->name, child_ic->pino_nlink); |
1da177e4 LT |
257 | jffs2_free_full_dirent(fd); |
258 | } | |
259 | } | |
260 | } | |
261 | ||
262 | /* | |
182ec4ee | 263 | We don't delete the inocache from the hash list and free it yet. |
1da177e4 LT |
264 | The erase code will do that, when all the nodes are completely gone. |
265 | */ | |
266 | } | |
267 | ||
268 | static 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 | ||
182ec4ee | 277 | /* Be conservative about how much space we need before we allow writes. |
1da177e4 LT |
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 | ||
182ec4ee | 292 | /* When do we allow garbage collection to merge nodes to make |
1da177e4 LT |
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 | ||
8fb870df DW |
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. */ | |
85becc53 | 304 | c->vdirty_blocks_gctrigger = c->resv_blocks_gctrigger; |
8fb870df DW |
305 | if (jffs2_can_mark_obsolete(c)) |
306 | c->vdirty_blocks_gctrigger *= 10; | |
307 | ||
1da177e4 LT |
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 | ||
5a528957 JP |
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); | |
733802d9 AB |
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); | |
8fb870df DW |
326 | dbg_fsbuild("Very dirty blocks before GC triggered: %d\n", |
327 | c->vdirty_blocks_gctrigger); | |
182ec4ee | 328 | } |
1da177e4 LT |
329 | |
330 | int jffs2_do_mount_fs(struct jffs2_sb_info *c) | |
331 | { | |
c617e842 | 332 | int ret; |
1da177e4 | 333 | int i; |
d55849aa | 334 | int size; |
1da177e4 LT |
335 | |
336 | c->free_size = c->flash_size; | |
337 | c->nr_blocks = c->flash_size / c->sector_size; | |
d55849aa | 338 | size = sizeof(struct jffs2_eraseblock) * c->nr_blocks; |
737b7661 | 339 | #ifndef __ECOS |
4ce1f562 | 340 | if (jffs2_blocks_use_vmalloc(c)) |
7ddbead6 | 341 | c->blocks = vzalloc(size); |
1da177e4 | 342 | else |
737b7661 | 343 | #endif |
7ddbead6 | 344 | c->blocks = kzalloc(size, GFP_KERNEL); |
1da177e4 LT |
345 | if (!c->blocks) |
346 | return -ENOMEM; | |
d55849aa | 347 | |
1da177e4 LT |
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; | |
1da177e4 LT |
352 | } |
353 | ||
1da177e4 LT |
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); | |
e2bc322b | 359 | INIT_LIST_HEAD(&c->erase_checking_list); |
1da177e4 LT |
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; | |
e631ddba FH |
367 | c->summary = NULL; |
368 | ||
c617e842 FH |
369 | ret = jffs2_sum_init(c); |
370 | if (ret) | |
cfa72397 | 371 | goto out_free; |
1da177e4 LT |
372 | |
373 | if (jffs2_build_filesystem(c)) { | |
733802d9 | 374 | dbg_fsbuild("build_fs failed\n"); |
1da177e4 LT |
375 | jffs2_free_ino_caches(c); |
376 | jffs2_free_raw_node_refs(c); | |
cfa72397 DA |
377 | ret = -EIO; |
378 | goto out_free; | |
1da177e4 LT |
379 | } |
380 | ||
381 | jffs2_calc_trigger_levels(c); | |
382 | ||
383 | return 0; | |
cfa72397 DA |
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; | |
1da177e4 | 394 | } |