diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/jffs2/compr.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/jffs2/compr.c')
-rw-r--r-- | fs/jffs2/compr.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/fs/jffs2/compr.c b/fs/jffs2/compr.c new file mode 100644 index 00000000000..af922a9618a --- /dev/null +++ b/fs/jffs2/compr.c | |||
@@ -0,0 +1,469 @@ | |||
1 | /* | ||
2 | * JFFS2 -- Journalling Flash File System, Version 2. | ||
3 | * | ||
4 | * Copyright (C) 2001-2003 Red Hat, Inc. | ||
5 | * Created by Arjan van de Ven <arjanv@redhat.com> | ||
6 | * | ||
7 | * Copyright (C) 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>, | ||
8 | * University of Szeged, Hungary | ||
9 | * | ||
10 | * For licensing information, see the file 'LICENCE' in this directory. | ||
11 | * | ||
12 | * $Id: compr.c,v 1.42 2004/08/07 21:56:08 dwmw2 Exp $ | ||
13 | * | ||
14 | */ | ||
15 | |||
16 | #include "compr.h" | ||
17 | |||
18 | static DEFINE_SPINLOCK(jffs2_compressor_list_lock); | ||
19 | |||
20 | /* Available compressors are on this list */ | ||
21 | static LIST_HEAD(jffs2_compressor_list); | ||
22 | |||
23 | /* Actual compression mode */ | ||
24 | static int jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; | ||
25 | |||
26 | /* Statistics for blocks stored without compression */ | ||
27 | static uint32_t none_stat_compr_blocks=0,none_stat_decompr_blocks=0,none_stat_compr_size=0; | ||
28 | |||
29 | /* jffs2_compress: | ||
30 | * @data: Pointer to uncompressed data | ||
31 | * @cdata: Pointer to returned pointer to buffer for compressed data | ||
32 | * @datalen: On entry, holds the amount of data available for compression. | ||
33 | * On exit, expected to hold the amount of data actually compressed. | ||
34 | * @cdatalen: On entry, holds the amount of space available for compressed | ||
35 | * data. On exit, expected to hold the actual size of the compressed | ||
36 | * data. | ||
37 | * | ||
38 | * Returns: Lower byte to be stored with data indicating compression type used. | ||
39 | * Zero is used to show that the data could not be compressed - the | ||
40 | * compressed version was actually larger than the original. | ||
41 | * Upper byte will be used later. (soon) | ||
42 | * | ||
43 | * If the cdata buffer isn't large enough to hold all the uncompressed data, | ||
44 | * jffs2_compress should compress as much as will fit, and should set | ||
45 | * *datalen accordingly to show the amount of data which were compressed. | ||
46 | */ | ||
47 | uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, | ||
48 | unsigned char *data_in, unsigned char **cpage_out, | ||
49 | uint32_t *datalen, uint32_t *cdatalen) | ||
50 | { | ||
51 | int ret = JFFS2_COMPR_NONE; | ||
52 | int compr_ret; | ||
53 | struct jffs2_compressor *this, *best=NULL; | ||
54 | unsigned char *output_buf = NULL, *tmp_buf; | ||
55 | uint32_t orig_slen, orig_dlen; | ||
56 | uint32_t best_slen=0, best_dlen=0; | ||
57 | |||
58 | switch (jffs2_compression_mode) { | ||
59 | case JFFS2_COMPR_MODE_NONE: | ||
60 | break; | ||
61 | case JFFS2_COMPR_MODE_PRIORITY: | ||
62 | output_buf = kmalloc(*cdatalen,GFP_KERNEL); | ||
63 | if (!output_buf) { | ||
64 | printk(KERN_WARNING "JFFS2: No memory for compressor allocation. Compression failed.\n"); | ||
65 | goto out; | ||
66 | } | ||
67 | orig_slen = *datalen; | ||
68 | orig_dlen = *cdatalen; | ||
69 | spin_lock(&jffs2_compressor_list_lock); | ||
70 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
71 | /* Skip decompress-only backwards-compatibility and disabled modules */ | ||
72 | if ((!this->compress)||(this->disabled)) | ||
73 | continue; | ||
74 | |||
75 | this->usecount++; | ||
76 | spin_unlock(&jffs2_compressor_list_lock); | ||
77 | *datalen = orig_slen; | ||
78 | *cdatalen = orig_dlen; | ||
79 | compr_ret = this->compress(data_in, output_buf, datalen, cdatalen, NULL); | ||
80 | spin_lock(&jffs2_compressor_list_lock); | ||
81 | this->usecount--; | ||
82 | if (!compr_ret) { | ||
83 | ret = this->compr; | ||
84 | this->stat_compr_blocks++; | ||
85 | this->stat_compr_orig_size += *datalen; | ||
86 | this->stat_compr_new_size += *cdatalen; | ||
87 | break; | ||
88 | } | ||
89 | } | ||
90 | spin_unlock(&jffs2_compressor_list_lock); | ||
91 | if (ret == JFFS2_COMPR_NONE) kfree(output_buf); | ||
92 | break; | ||
93 | case JFFS2_COMPR_MODE_SIZE: | ||
94 | orig_slen = *datalen; | ||
95 | orig_dlen = *cdatalen; | ||
96 | spin_lock(&jffs2_compressor_list_lock); | ||
97 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
98 | /* Skip decompress-only backwards-compatibility and disabled modules */ | ||
99 | if ((!this->compress)||(this->disabled)) | ||
100 | continue; | ||
101 | /* Allocating memory for output buffer if necessary */ | ||
102 | if ((this->compr_buf_size<orig_dlen)&&(this->compr_buf)) { | ||
103 | spin_unlock(&jffs2_compressor_list_lock); | ||
104 | kfree(this->compr_buf); | ||
105 | spin_lock(&jffs2_compressor_list_lock); | ||
106 | this->compr_buf_size=0; | ||
107 | this->compr_buf=NULL; | ||
108 | } | ||
109 | if (!this->compr_buf) { | ||
110 | spin_unlock(&jffs2_compressor_list_lock); | ||
111 | tmp_buf = kmalloc(orig_dlen,GFP_KERNEL); | ||
112 | spin_lock(&jffs2_compressor_list_lock); | ||
113 | if (!tmp_buf) { | ||
114 | printk(KERN_WARNING "JFFS2: No memory for compressor allocation. (%d bytes)\n",orig_dlen); | ||
115 | continue; | ||
116 | } | ||
117 | else { | ||
118 | this->compr_buf = tmp_buf; | ||
119 | this->compr_buf_size = orig_dlen; | ||
120 | } | ||
121 | } | ||
122 | this->usecount++; | ||
123 | spin_unlock(&jffs2_compressor_list_lock); | ||
124 | *datalen = orig_slen; | ||
125 | *cdatalen = orig_dlen; | ||
126 | compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen, NULL); | ||
127 | spin_lock(&jffs2_compressor_list_lock); | ||
128 | this->usecount--; | ||
129 | if (!compr_ret) { | ||
130 | if ((!best_dlen)||(best_dlen>*cdatalen)) { | ||
131 | best_dlen = *cdatalen; | ||
132 | best_slen = *datalen; | ||
133 | best = this; | ||
134 | } | ||
135 | } | ||
136 | } | ||
137 | if (best_dlen) { | ||
138 | *cdatalen = best_dlen; | ||
139 | *datalen = best_slen; | ||
140 | output_buf = best->compr_buf; | ||
141 | best->compr_buf = NULL; | ||
142 | best->compr_buf_size = 0; | ||
143 | best->stat_compr_blocks++; | ||
144 | best->stat_compr_orig_size += best_slen; | ||
145 | best->stat_compr_new_size += best_dlen; | ||
146 | ret = best->compr; | ||
147 | } | ||
148 | spin_unlock(&jffs2_compressor_list_lock); | ||
149 | break; | ||
150 | default: | ||
151 | printk(KERN_ERR "JFFS2: unknow compression mode.\n"); | ||
152 | } | ||
153 | out: | ||
154 | if (ret == JFFS2_COMPR_NONE) { | ||
155 | *cpage_out = data_in; | ||
156 | *datalen = *cdatalen; | ||
157 | none_stat_compr_blocks++; | ||
158 | none_stat_compr_size += *datalen; | ||
159 | } | ||
160 | else { | ||
161 | *cpage_out = output_buf; | ||
162 | } | ||
163 | return ret; | ||
164 | } | ||
165 | |||
166 | int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, | ||
167 | uint16_t comprtype, unsigned char *cdata_in, | ||
168 | unsigned char *data_out, uint32_t cdatalen, uint32_t datalen) | ||
169 | { | ||
170 | struct jffs2_compressor *this; | ||
171 | int ret; | ||
172 | |||
173 | /* Older code had a bug where it would write non-zero 'usercompr' | ||
174 | fields. Deal with it. */ | ||
175 | if ((comprtype & 0xff) <= JFFS2_COMPR_ZLIB) | ||
176 | comprtype &= 0xff; | ||
177 | |||
178 | switch (comprtype & 0xff) { | ||
179 | case JFFS2_COMPR_NONE: | ||
180 | /* This should be special-cased elsewhere, but we might as well deal with it */ | ||
181 | memcpy(data_out, cdata_in, datalen); | ||
182 | none_stat_decompr_blocks++; | ||
183 | break; | ||
184 | case JFFS2_COMPR_ZERO: | ||
185 | memset(data_out, 0, datalen); | ||
186 | break; | ||
187 | default: | ||
188 | spin_lock(&jffs2_compressor_list_lock); | ||
189 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
190 | if (comprtype == this->compr) { | ||
191 | this->usecount++; | ||
192 | spin_unlock(&jffs2_compressor_list_lock); | ||
193 | ret = this->decompress(cdata_in, data_out, cdatalen, datalen, NULL); | ||
194 | spin_lock(&jffs2_compressor_list_lock); | ||
195 | if (ret) { | ||
196 | printk(KERN_WARNING "Decompressor \"%s\" returned %d\n", this->name, ret); | ||
197 | } | ||
198 | else { | ||
199 | this->stat_decompr_blocks++; | ||
200 | } | ||
201 | this->usecount--; | ||
202 | spin_unlock(&jffs2_compressor_list_lock); | ||
203 | return ret; | ||
204 | } | ||
205 | } | ||
206 | printk(KERN_WARNING "JFFS2 compression type 0x%02x not available.\n", comprtype); | ||
207 | spin_unlock(&jffs2_compressor_list_lock); | ||
208 | return -EIO; | ||
209 | } | ||
210 | return 0; | ||
211 | } | ||
212 | |||
213 | int jffs2_register_compressor(struct jffs2_compressor *comp) | ||
214 | { | ||
215 | struct jffs2_compressor *this; | ||
216 | |||
217 | if (!comp->name) { | ||
218 | printk(KERN_WARNING "NULL compressor name at registering JFFS2 compressor. Failed.\n"); | ||
219 | return -1; | ||
220 | } | ||
221 | comp->compr_buf_size=0; | ||
222 | comp->compr_buf=NULL; | ||
223 | comp->usecount=0; | ||
224 | comp->stat_compr_orig_size=0; | ||
225 | comp->stat_compr_new_size=0; | ||
226 | comp->stat_compr_blocks=0; | ||
227 | comp->stat_decompr_blocks=0; | ||
228 | D1(printk(KERN_DEBUG "Registering JFFS2 compressor \"%s\"\n", comp->name)); | ||
229 | |||
230 | spin_lock(&jffs2_compressor_list_lock); | ||
231 | |||
232 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
233 | if (this->priority < comp->priority) { | ||
234 | list_add(&comp->list, this->list.prev); | ||
235 | goto out; | ||
236 | } | ||
237 | } | ||
238 | list_add_tail(&comp->list, &jffs2_compressor_list); | ||
239 | out: | ||
240 | D2(list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
241 | printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); | ||
242 | }) | ||
243 | |||
244 | spin_unlock(&jffs2_compressor_list_lock); | ||
245 | |||
246 | return 0; | ||
247 | } | ||
248 | |||
249 | int jffs2_unregister_compressor(struct jffs2_compressor *comp) | ||
250 | { | ||
251 | D2(struct jffs2_compressor *this;) | ||
252 | |||
253 | D1(printk(KERN_DEBUG "Unregistering JFFS2 compressor \"%s\"\n", comp->name)); | ||
254 | |||
255 | spin_lock(&jffs2_compressor_list_lock); | ||
256 | |||
257 | if (comp->usecount) { | ||
258 | spin_unlock(&jffs2_compressor_list_lock); | ||
259 | printk(KERN_WARNING "JFFS2: Compressor modul is in use. Unregister failed.\n"); | ||
260 | return -1; | ||
261 | } | ||
262 | list_del(&comp->list); | ||
263 | |||
264 | D2(list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
265 | printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); | ||
266 | }) | ||
267 | spin_unlock(&jffs2_compressor_list_lock); | ||
268 | return 0; | ||
269 | } | ||
270 | |||
271 | #ifdef CONFIG_JFFS2_PROC | ||
272 | |||
273 | #define JFFS2_STAT_BUF_SIZE 16000 | ||
274 | |||
275 | char *jffs2_list_compressors(void) | ||
276 | { | ||
277 | struct jffs2_compressor *this; | ||
278 | char *buf, *act_buf; | ||
279 | |||
280 | act_buf = buf = kmalloc(JFFS2_STAT_BUF_SIZE,GFP_KERNEL); | ||
281 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
282 | act_buf += sprintf(act_buf, "%10s priority:%d ", this->name, this->priority); | ||
283 | if ((this->disabled)||(!this->compress)) | ||
284 | act_buf += sprintf(act_buf,"disabled"); | ||
285 | else | ||
286 | act_buf += sprintf(act_buf,"enabled"); | ||
287 | act_buf += sprintf(act_buf,"\n"); | ||
288 | } | ||
289 | return buf; | ||
290 | } | ||
291 | |||
292 | char *jffs2_stats(void) | ||
293 | { | ||
294 | struct jffs2_compressor *this; | ||
295 | char *buf, *act_buf; | ||
296 | |||
297 | act_buf = buf = kmalloc(JFFS2_STAT_BUF_SIZE,GFP_KERNEL); | ||
298 | |||
299 | act_buf += sprintf(act_buf,"JFFS2 compressor statistics:\n"); | ||
300 | act_buf += sprintf(act_buf,"%10s ","none"); | ||
301 | act_buf += sprintf(act_buf,"compr: %d blocks (%d) decompr: %d blocks\n", none_stat_compr_blocks, | ||
302 | none_stat_compr_size, none_stat_decompr_blocks); | ||
303 | spin_lock(&jffs2_compressor_list_lock); | ||
304 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
305 | act_buf += sprintf(act_buf,"%10s ",this->name); | ||
306 | if ((this->disabled)||(!this->compress)) | ||
307 | act_buf += sprintf(act_buf,"- "); | ||
308 | else | ||
309 | act_buf += sprintf(act_buf,"+ "); | ||
310 | act_buf += sprintf(act_buf,"compr: %d blocks (%d/%d) decompr: %d blocks ", this->stat_compr_blocks, | ||
311 | this->stat_compr_new_size, this->stat_compr_orig_size, | ||
312 | this->stat_decompr_blocks); | ||
313 | act_buf += sprintf(act_buf,"\n"); | ||
314 | } | ||
315 | spin_unlock(&jffs2_compressor_list_lock); | ||
316 | |||
317 | return buf; | ||
318 | } | ||
319 | |||
320 | char *jffs2_get_compression_mode_name(void) | ||
321 | { | ||
322 | switch (jffs2_compression_mode) { | ||
323 | case JFFS2_COMPR_MODE_NONE: | ||
324 | return "none"; | ||
325 | case JFFS2_COMPR_MODE_PRIORITY: | ||
326 | return "priority"; | ||
327 | case JFFS2_COMPR_MODE_SIZE: | ||
328 | return "size"; | ||
329 | } | ||
330 | return "unkown"; | ||
331 | } | ||
332 | |||
333 | int jffs2_set_compression_mode_name(const char *name) | ||
334 | { | ||
335 | if (!strcmp("none",name)) { | ||
336 | jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; | ||
337 | return 0; | ||
338 | } | ||
339 | if (!strcmp("priority",name)) { | ||
340 | jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; | ||
341 | return 0; | ||
342 | } | ||
343 | if (!strcmp("size",name)) { | ||
344 | jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; | ||
345 | return 0; | ||
346 | } | ||
347 | return 1; | ||
348 | } | ||
349 | |||
350 | static int jffs2_compressor_Xable(const char *name, int disabled) | ||
351 | { | ||
352 | struct jffs2_compressor *this; | ||
353 | spin_lock(&jffs2_compressor_list_lock); | ||
354 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
355 | if (!strcmp(this->name, name)) { | ||
356 | this->disabled = disabled; | ||
357 | spin_unlock(&jffs2_compressor_list_lock); | ||
358 | return 0; | ||
359 | } | ||
360 | } | ||
361 | spin_unlock(&jffs2_compressor_list_lock); | ||
362 | printk(KERN_WARNING "JFFS2: compressor %s not found.\n",name); | ||
363 | return 1; | ||
364 | } | ||
365 | |||
366 | int jffs2_enable_compressor_name(const char *name) | ||
367 | { | ||
368 | return jffs2_compressor_Xable(name, 0); | ||
369 | } | ||
370 | |||
371 | int jffs2_disable_compressor_name(const char *name) | ||
372 | { | ||
373 | return jffs2_compressor_Xable(name, 1); | ||
374 | } | ||
375 | |||
376 | int jffs2_set_compressor_priority(const char *name, int priority) | ||
377 | { | ||
378 | struct jffs2_compressor *this,*comp; | ||
379 | spin_lock(&jffs2_compressor_list_lock); | ||
380 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
381 | if (!strcmp(this->name, name)) { | ||
382 | this->priority = priority; | ||
383 | comp = this; | ||
384 | goto reinsert; | ||
385 | } | ||
386 | } | ||
387 | spin_unlock(&jffs2_compressor_list_lock); | ||
388 | printk(KERN_WARNING "JFFS2: compressor %s not found.\n",name); | ||
389 | return 1; | ||
390 | reinsert: | ||
391 | /* list is sorted in the order of priority, so if | ||
392 | we change it we have to reinsert it into the | ||
393 | good place */ | ||
394 | list_del(&comp->list); | ||
395 | list_for_each_entry(this, &jffs2_compressor_list, list) { | ||
396 | if (this->priority < comp->priority) { | ||
397 | list_add(&comp->list, this->list.prev); | ||
398 | spin_unlock(&jffs2_compressor_list_lock); | ||
399 | return 0; | ||
400 | } | ||
401 | } | ||
402 | list_add_tail(&comp->list, &jffs2_compressor_list); | ||
403 | spin_unlock(&jffs2_compressor_list_lock); | ||
404 | return 0; | ||
405 | } | ||
406 | |||
407 | #endif | ||
408 | |||
409 | void jffs2_free_comprbuf(unsigned char *comprbuf, unsigned char *orig) | ||
410 | { | ||
411 | if (orig != comprbuf) | ||
412 | kfree(comprbuf); | ||
413 | } | ||
414 | |||
415 | int jffs2_compressors_init(void) | ||
416 | { | ||
417 | /* Registering compressors */ | ||
418 | #ifdef CONFIG_JFFS2_ZLIB | ||
419 | jffs2_zlib_init(); | ||
420 | #endif | ||
421 | #ifdef CONFIG_JFFS2_RTIME | ||
422 | jffs2_rtime_init(); | ||
423 | #endif | ||
424 | #ifdef CONFIG_JFFS2_RUBIN | ||
425 | jffs2_rubinmips_init(); | ||
426 | jffs2_dynrubin_init(); | ||
427 | #endif | ||
428 | #ifdef CONFIG_JFFS2_LZARI | ||
429 | jffs2_lzari_init(); | ||
430 | #endif | ||
431 | #ifdef CONFIG_JFFS2_LZO | ||
432 | jffs2_lzo_init(); | ||
433 | #endif | ||
434 | /* Setting default compression mode */ | ||
435 | #ifdef CONFIG_JFFS2_CMODE_NONE | ||
436 | jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; | ||
437 | D1(printk(KERN_INFO "JFFS2: default compression mode: none\n");) | ||
438 | #else | ||
439 | #ifdef CONFIG_JFFS2_CMODE_SIZE | ||
440 | jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; | ||
441 | D1(printk(KERN_INFO "JFFS2: default compression mode: size\n");) | ||
442 | #else | ||
443 | D1(printk(KERN_INFO "JFFS2: default compression mode: priority\n");) | ||
444 | #endif | ||
445 | #endif | ||
446 | return 0; | ||
447 | } | ||
448 | |||
449 | int jffs2_compressors_exit(void) | ||
450 | { | ||
451 | /* Unregistering compressors */ | ||
452 | #ifdef CONFIG_JFFS2_LZO | ||
453 | jffs2_lzo_exit(); | ||
454 | #endif | ||
455 | #ifdef CONFIG_JFFS2_LZARI | ||
456 | jffs2_lzari_exit(); | ||
457 | #endif | ||
458 | #ifdef CONFIG_JFFS2_RUBIN | ||
459 | jffs2_dynrubin_exit(); | ||
460 | jffs2_rubinmips_exit(); | ||
461 | #endif | ||
462 | #ifdef CONFIG_JFFS2_RTIME | ||
463 | jffs2_rtime_exit(); | ||
464 | #endif | ||
465 | #ifdef CONFIG_JFFS2_ZLIB | ||
466 | jffs2_zlib_exit(); | ||
467 | #endif | ||
468 | return 0; | ||
469 | } | ||