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1 | /* | |
2 | * logfile.c - NTFS kernel journal handling. Part of the Linux-NTFS project. | |
3 | * | |
4 | * Copyright (c) 2002-2007 Anton Altaparmakov | |
5 | * | |
6 | * This program/include file is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License as published | |
8 | * by the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program/include file is distributed in the hope that it will be | |
12 | * useful, but WITHOUT ANY WARRANTY; without even the implied warranty | |
13 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program (in the main directory of the Linux-NTFS | |
18 | * distribution in the file COPYING); if not, write to the Free Software | |
19 | * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | */ | |
21 | ||
22 | #ifdef NTFS_RW | |
23 | ||
24 | #include <linux/types.h> | |
25 | #include <linux/fs.h> | |
26 | #include <linux/highmem.h> | |
27 | #include <linux/buffer_head.h> | |
28 | #include <linux/bitops.h> | |
29 | #include <linux/log2.h> | |
30 | ||
31 | #include "attrib.h" | |
32 | #include "aops.h" | |
33 | #include "debug.h" | |
34 | #include "logfile.h" | |
35 | #include "malloc.h" | |
36 | #include "volume.h" | |
37 | #include "ntfs.h" | |
38 | ||
39 | /** | |
40 | * ntfs_check_restart_page_header - check the page header for consistency | |
41 | * @vi: $LogFile inode to which the restart page header belongs | |
42 | * @rp: restart page header to check | |
43 | * @pos: position in @vi at which the restart page header resides | |
44 | * | |
45 | * Check the restart page header @rp for consistency and return 'true' if it is | |
46 | * consistent and 'false' otherwise. | |
47 | * | |
48 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
49 | * require the full restart page. | |
50 | */ | |
51 | static bool ntfs_check_restart_page_header(struct inode *vi, | |
52 | RESTART_PAGE_HEADER *rp, s64 pos) | |
53 | { | |
54 | u32 logfile_system_page_size, logfile_log_page_size; | |
55 | u16 ra_ofs, usa_count, usa_ofs, usa_end = 0; | |
56 | bool have_usa = true; | |
57 | ||
58 | ntfs_debug("Entering."); | |
59 | /* | |
60 | * If the system or log page sizes are smaller than the ntfs block size | |
61 | * or either is not a power of 2 we cannot handle this log file. | |
62 | */ | |
63 | logfile_system_page_size = le32_to_cpu(rp->system_page_size); | |
64 | logfile_log_page_size = le32_to_cpu(rp->log_page_size); | |
65 | if (logfile_system_page_size < NTFS_BLOCK_SIZE || | |
66 | logfile_log_page_size < NTFS_BLOCK_SIZE || | |
67 | logfile_system_page_size & | |
68 | (logfile_system_page_size - 1) || | |
69 | !is_power_of_2(logfile_log_page_size)) { | |
70 | ntfs_error(vi->i_sb, "$LogFile uses unsupported page size."); | |
71 | return false; | |
72 | } | |
73 | /* | |
74 | * We must be either at !pos (1st restart page) or at pos = system page | |
75 | * size (2nd restart page). | |
76 | */ | |
77 | if (pos && pos != logfile_system_page_size) { | |
78 | ntfs_error(vi->i_sb, "Found restart area in incorrect " | |
79 | "position in $LogFile."); | |
80 | return false; | |
81 | } | |
82 | /* We only know how to handle version 1.1. */ | |
83 | if (sle16_to_cpu(rp->major_ver) != 1 || | |
84 | sle16_to_cpu(rp->minor_ver) != 1) { | |
85 | ntfs_error(vi->i_sb, "$LogFile version %i.%i is not " | |
86 | "supported. (This driver supports version " | |
87 | "1.1 only.)", (int)sle16_to_cpu(rp->major_ver), | |
88 | (int)sle16_to_cpu(rp->minor_ver)); | |
89 | return false; | |
90 | } | |
91 | /* | |
92 | * If chkdsk has been run the restart page may not be protected by an | |
93 | * update sequence array. | |
94 | */ | |
95 | if (ntfs_is_chkd_record(rp->magic) && !le16_to_cpu(rp->usa_count)) { | |
96 | have_usa = false; | |
97 | goto skip_usa_checks; | |
98 | } | |
99 | /* Verify the size of the update sequence array. */ | |
100 | usa_count = 1 + (logfile_system_page_size >> NTFS_BLOCK_SIZE_BITS); | |
101 | if (usa_count != le16_to_cpu(rp->usa_count)) { | |
102 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
103 | "inconsistent update sequence array count."); | |
104 | return false; | |
105 | } | |
106 | /* Verify the position of the update sequence array. */ | |
107 | usa_ofs = le16_to_cpu(rp->usa_ofs); | |
108 | usa_end = usa_ofs + usa_count * sizeof(u16); | |
109 | if (usa_ofs < sizeof(RESTART_PAGE_HEADER) || | |
110 | usa_end > NTFS_BLOCK_SIZE - sizeof(u16)) { | |
111 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
112 | "inconsistent update sequence array offset."); | |
113 | return false; | |
114 | } | |
115 | skip_usa_checks: | |
116 | /* | |
117 | * Verify the position of the restart area. It must be: | |
118 | * - aligned to 8-byte boundary, | |
119 | * - after the update sequence array, and | |
120 | * - within the system page size. | |
121 | */ | |
122 | ra_ofs = le16_to_cpu(rp->restart_area_offset); | |
123 | if (ra_ofs & 7 || (have_usa ? ra_ofs < usa_end : | |
124 | ra_ofs < sizeof(RESTART_PAGE_HEADER)) || | |
125 | ra_ofs > logfile_system_page_size) { | |
126 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
127 | "inconsistent restart area offset."); | |
128 | return false; | |
129 | } | |
130 | /* | |
131 | * Only restart pages modified by chkdsk are allowed to have chkdsk_lsn | |
132 | * set. | |
133 | */ | |
134 | if (!ntfs_is_chkd_record(rp->magic) && sle64_to_cpu(rp->chkdsk_lsn)) { | |
135 | ntfs_error(vi->i_sb, "$LogFile restart page is not modified " | |
136 | "by chkdsk but a chkdsk LSN is specified."); | |
137 | return false; | |
138 | } | |
139 | ntfs_debug("Done."); | |
140 | return true; | |
141 | } | |
142 | ||
143 | /** | |
144 | * ntfs_check_restart_area - check the restart area for consistency | |
145 | * @vi: $LogFile inode to which the restart page belongs | |
146 | * @rp: restart page whose restart area to check | |
147 | * | |
148 | * Check the restart area of the restart page @rp for consistency and return | |
149 | * 'true' if it is consistent and 'false' otherwise. | |
150 | * | |
151 | * This function assumes that the restart page header has already been | |
152 | * consistency checked. | |
153 | * | |
154 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
155 | * require the full restart page. | |
156 | */ | |
157 | static bool ntfs_check_restart_area(struct inode *vi, RESTART_PAGE_HEADER *rp) | |
158 | { | |
159 | u64 file_size; | |
160 | RESTART_AREA *ra; | |
161 | u16 ra_ofs, ra_len, ca_ofs; | |
162 | u8 fs_bits; | |
163 | ||
164 | ntfs_debug("Entering."); | |
165 | ra_ofs = le16_to_cpu(rp->restart_area_offset); | |
166 | ra = (RESTART_AREA*)((u8*)rp + ra_ofs); | |
167 | /* | |
168 | * Everything before ra->file_size must be before the first word | |
169 | * protected by an update sequence number. This ensures that it is | |
170 | * safe to access ra->client_array_offset. | |
171 | */ | |
172 | if (ra_ofs + offsetof(RESTART_AREA, file_size) > | |
173 | NTFS_BLOCK_SIZE - sizeof(u16)) { | |
174 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
175 | "inconsistent file offset."); | |
176 | return false; | |
177 | } | |
178 | /* | |
179 | * Now that we can access ra->client_array_offset, make sure everything | |
180 | * up to the log client array is before the first word protected by an | |
181 | * update sequence number. This ensures we can access all of the | |
182 | * restart area elements safely. Also, the client array offset must be | |
183 | * aligned to an 8-byte boundary. | |
184 | */ | |
185 | ca_ofs = le16_to_cpu(ra->client_array_offset); | |
186 | if (((ca_ofs + 7) & ~7) != ca_ofs || | |
187 | ra_ofs + ca_ofs > NTFS_BLOCK_SIZE - sizeof(u16)) { | |
188 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
189 | "inconsistent client array offset."); | |
190 | return false; | |
191 | } | |
192 | /* | |
193 | * The restart area must end within the system page size both when | |
194 | * calculated manually and as specified by ra->restart_area_length. | |
195 | * Also, the calculated length must not exceed the specified length. | |
196 | */ | |
197 | ra_len = ca_ofs + le16_to_cpu(ra->log_clients) * | |
198 | sizeof(LOG_CLIENT_RECORD); | |
199 | if (ra_ofs + ra_len > le32_to_cpu(rp->system_page_size) || | |
200 | ra_ofs + le16_to_cpu(ra->restart_area_length) > | |
201 | le32_to_cpu(rp->system_page_size) || | |
202 | ra_len > le16_to_cpu(ra->restart_area_length)) { | |
203 | ntfs_error(vi->i_sb, "$LogFile restart area is out of bounds " | |
204 | "of the system page size specified by the " | |
205 | "restart page header and/or the specified " | |
206 | "restart area length is inconsistent."); | |
207 | return false; | |
208 | } | |
209 | /* | |
210 | * The ra->client_free_list and ra->client_in_use_list must be either | |
211 | * LOGFILE_NO_CLIENT or less than ra->log_clients or they are | |
212 | * overflowing the client array. | |
213 | */ | |
214 | if ((ra->client_free_list != LOGFILE_NO_CLIENT && | |
215 | le16_to_cpu(ra->client_free_list) >= | |
216 | le16_to_cpu(ra->log_clients)) || | |
217 | (ra->client_in_use_list != LOGFILE_NO_CLIENT && | |
218 | le16_to_cpu(ra->client_in_use_list) >= | |
219 | le16_to_cpu(ra->log_clients))) { | |
220 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
221 | "overflowing client free and/or in use lists."); | |
222 | return false; | |
223 | } | |
224 | /* | |
225 | * Check ra->seq_number_bits against ra->file_size for consistency. | |
226 | * We cannot just use ffs() because the file size is not a power of 2. | |
227 | */ | |
228 | file_size = (u64)sle64_to_cpu(ra->file_size); | |
229 | fs_bits = 0; | |
230 | while (file_size) { | |
231 | file_size >>= 1; | |
232 | fs_bits++; | |
233 | } | |
234 | if (le32_to_cpu(ra->seq_number_bits) != 67 - fs_bits) { | |
235 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
236 | "inconsistent sequence number bits."); | |
237 | return false; | |
238 | } | |
239 | /* The log record header length must be a multiple of 8. */ | |
240 | if (((le16_to_cpu(ra->log_record_header_length) + 7) & ~7) != | |
241 | le16_to_cpu(ra->log_record_header_length)) { | |
242 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
243 | "inconsistent log record header length."); | |
244 | return false; | |
245 | } | |
246 | /* Dito for the log page data offset. */ | |
247 | if (((le16_to_cpu(ra->log_page_data_offset) + 7) & ~7) != | |
248 | le16_to_cpu(ra->log_page_data_offset)) { | |
249 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
250 | "inconsistent log page data offset."); | |
251 | return false; | |
252 | } | |
253 | ntfs_debug("Done."); | |
254 | return true; | |
255 | } | |
256 | ||
257 | /** | |
258 | * ntfs_check_log_client_array - check the log client array for consistency | |
259 | * @vi: $LogFile inode to which the restart page belongs | |
260 | * @rp: restart page whose log client array to check | |
261 | * | |
262 | * Check the log client array of the restart page @rp for consistency and | |
263 | * return 'true' if it is consistent and 'false' otherwise. | |
264 | * | |
265 | * This function assumes that the restart page header and the restart area have | |
266 | * already been consistency checked. | |
267 | * | |
268 | * Unlike ntfs_check_restart_page_header() and ntfs_check_restart_area(), this | |
269 | * function needs @rp->system_page_size bytes in @rp, i.e. it requires the full | |
270 | * restart page and the page must be multi sector transfer deprotected. | |
271 | */ | |
272 | static bool ntfs_check_log_client_array(struct inode *vi, | |
273 | RESTART_PAGE_HEADER *rp) | |
274 | { | |
275 | RESTART_AREA *ra; | |
276 | LOG_CLIENT_RECORD *ca, *cr; | |
277 | u16 nr_clients, idx; | |
278 | bool in_free_list, idx_is_first; | |
279 | ||
280 | ntfs_debug("Entering."); | |
281 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); | |
282 | ca = (LOG_CLIENT_RECORD*)((u8*)ra + | |
283 | le16_to_cpu(ra->client_array_offset)); | |
284 | /* | |
285 | * Check the ra->client_free_list first and then check the | |
286 | * ra->client_in_use_list. Check each of the log client records in | |
287 | * each of the lists and check that the array does not overflow the | |
288 | * ra->log_clients value. Also keep track of the number of records | |
289 | * visited as there cannot be more than ra->log_clients records and | |
290 | * that way we detect eventual loops in within a list. | |
291 | */ | |
292 | nr_clients = le16_to_cpu(ra->log_clients); | |
293 | idx = le16_to_cpu(ra->client_free_list); | |
294 | in_free_list = true; | |
295 | check_list: | |
296 | for (idx_is_first = true; idx != LOGFILE_NO_CLIENT_CPU; nr_clients--, | |
297 | idx = le16_to_cpu(cr->next_client)) { | |
298 | if (!nr_clients || idx >= le16_to_cpu(ra->log_clients)) | |
299 | goto err_out; | |
300 | /* Set @cr to the current log client record. */ | |
301 | cr = ca + idx; | |
302 | /* The first log client record must not have a prev_client. */ | |
303 | if (idx_is_first) { | |
304 | if (cr->prev_client != LOGFILE_NO_CLIENT) | |
305 | goto err_out; | |
306 | idx_is_first = false; | |
307 | } | |
308 | } | |
309 | /* Switch to and check the in use list if we just did the free list. */ | |
310 | if (in_free_list) { | |
311 | in_free_list = false; | |
312 | idx = le16_to_cpu(ra->client_in_use_list); | |
313 | goto check_list; | |
314 | } | |
315 | ntfs_debug("Done."); | |
316 | return true; | |
317 | err_out: | |
318 | ntfs_error(vi->i_sb, "$LogFile log client array is corrupt."); | |
319 | return false; | |
320 | } | |
321 | ||
322 | /** | |
323 | * ntfs_check_and_load_restart_page - check the restart page for consistency | |
324 | * @vi: $LogFile inode to which the restart page belongs | |
325 | * @rp: restart page to check | |
326 | * @pos: position in @vi at which the restart page resides | |
327 | * @wrp: [OUT] copy of the multi sector transfer deprotected restart page | |
328 | * @lsn: [OUT] set to the current logfile lsn on success | |
329 | * | |
330 | * Check the restart page @rp for consistency and return 0 if it is consistent | |
331 | * and -errno otherwise. The restart page may have been modified by chkdsk in | |
332 | * which case its magic is CHKD instead of RSTR. | |
333 | * | |
334 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
335 | * require the full restart page. | |
336 | * | |
337 | * If @wrp is not NULL, on success, *@wrp will point to a buffer containing a | |
338 | * copy of the complete multi sector transfer deprotected page. On failure, | |
339 | * *@wrp is undefined. | |
340 | * | |
341 | * Simillarly, if @lsn is not NULL, on success *@lsn will be set to the current | |
342 | * logfile lsn according to this restart page. On failure, *@lsn is undefined. | |
343 | * | |
344 | * The following error codes are defined: | |
345 | * -EINVAL - The restart page is inconsistent. | |
346 | * -ENOMEM - Not enough memory to load the restart page. | |
347 | * -EIO - Failed to reading from $LogFile. | |
348 | */ | |
349 | static int ntfs_check_and_load_restart_page(struct inode *vi, | |
350 | RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp, | |
351 | LSN *lsn) | |
352 | { | |
353 | RESTART_AREA *ra; | |
354 | RESTART_PAGE_HEADER *trp; | |
355 | int size, err; | |
356 | ||
357 | ntfs_debug("Entering."); | |
358 | /* Check the restart page header for consistency. */ | |
359 | if (!ntfs_check_restart_page_header(vi, rp, pos)) { | |
360 | /* Error output already done inside the function. */ | |
361 | return -EINVAL; | |
362 | } | |
363 | /* Check the restart area for consistency. */ | |
364 | if (!ntfs_check_restart_area(vi, rp)) { | |
365 | /* Error output already done inside the function. */ | |
366 | return -EINVAL; | |
367 | } | |
368 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); | |
369 | /* | |
370 | * Allocate a buffer to store the whole restart page so we can multi | |
371 | * sector transfer deprotect it. | |
372 | */ | |
373 | trp = ntfs_malloc_nofs(le32_to_cpu(rp->system_page_size)); | |
374 | if (!trp) { | |
375 | ntfs_error(vi->i_sb, "Failed to allocate memory for $LogFile " | |
376 | "restart page buffer."); | |
377 | return -ENOMEM; | |
378 | } | |
379 | /* | |
380 | * Read the whole of the restart page into the buffer. If it fits | |
381 | * completely inside @rp, just copy it from there. Otherwise map all | |
382 | * the required pages and copy the data from them. | |
383 | */ | |
384 | size = PAGE_CACHE_SIZE - (pos & ~PAGE_CACHE_MASK); | |
385 | if (size >= le32_to_cpu(rp->system_page_size)) { | |
386 | memcpy(trp, rp, le32_to_cpu(rp->system_page_size)); | |
387 | } else { | |
388 | pgoff_t idx; | |
389 | struct page *page; | |
390 | int have_read, to_read; | |
391 | ||
392 | /* First copy what we already have in @rp. */ | |
393 | memcpy(trp, rp, size); | |
394 | /* Copy the remaining data one page at a time. */ | |
395 | have_read = size; | |
396 | to_read = le32_to_cpu(rp->system_page_size) - size; | |
397 | idx = (pos + size) >> PAGE_CACHE_SHIFT; | |
398 | BUG_ON((pos + size) & ~PAGE_CACHE_MASK); | |
399 | do { | |
400 | page = ntfs_map_page(vi->i_mapping, idx); | |
401 | if (IS_ERR(page)) { | |
402 | ntfs_error(vi->i_sb, "Error mapping $LogFile " | |
403 | "page (index %lu).", idx); | |
404 | err = PTR_ERR(page); | |
405 | if (err != -EIO && err != -ENOMEM) | |
406 | err = -EIO; | |
407 | goto err_out; | |
408 | } | |
409 | size = min_t(int, to_read, PAGE_CACHE_SIZE); | |
410 | memcpy((u8*)trp + have_read, page_address(page), size); | |
411 | ntfs_unmap_page(page); | |
412 | have_read += size; | |
413 | to_read -= size; | |
414 | idx++; | |
415 | } while (to_read > 0); | |
416 | } | |
417 | /* | |
418 | * Perform the multi sector transfer deprotection on the buffer if the | |
419 | * restart page is protected. | |
420 | */ | |
421 | if ((!ntfs_is_chkd_record(trp->magic) || le16_to_cpu(trp->usa_count)) | |
422 | && post_read_mst_fixup((NTFS_RECORD*)trp, | |
423 | le32_to_cpu(rp->system_page_size))) { | |
424 | /* | |
425 | * A multi sector tranfer error was detected. We only need to | |
426 | * abort if the restart page contents exceed the multi sector | |
427 | * transfer fixup of the first sector. | |
428 | */ | |
429 | if (le16_to_cpu(rp->restart_area_offset) + | |
430 | le16_to_cpu(ra->restart_area_length) > | |
431 | NTFS_BLOCK_SIZE - sizeof(u16)) { | |
432 | ntfs_error(vi->i_sb, "Multi sector transfer error " | |
433 | "detected in $LogFile restart page."); | |
434 | err = -EINVAL; | |
435 | goto err_out; | |
436 | } | |
437 | } | |
438 | /* | |
439 | * If the restart page is modified by chkdsk or there are no active | |
440 | * logfile clients, the logfile is consistent. Otherwise, need to | |
441 | * check the log client records for consistency, too. | |
442 | */ | |
443 | err = 0; | |
444 | if (ntfs_is_rstr_record(rp->magic) && | |
445 | ra->client_in_use_list != LOGFILE_NO_CLIENT) { | |
446 | if (!ntfs_check_log_client_array(vi, trp)) { | |
447 | err = -EINVAL; | |
448 | goto err_out; | |
449 | } | |
450 | } | |
451 | if (lsn) { | |
452 | if (ntfs_is_rstr_record(rp->magic)) | |
453 | *lsn = sle64_to_cpu(ra->current_lsn); | |
454 | else /* if (ntfs_is_chkd_record(rp->magic)) */ | |
455 | *lsn = sle64_to_cpu(rp->chkdsk_lsn); | |
456 | } | |
457 | ntfs_debug("Done."); | |
458 | if (wrp) | |
459 | *wrp = trp; | |
460 | else { | |
461 | err_out: | |
462 | ntfs_free(trp); | |
463 | } | |
464 | return err; | |
465 | } | |
466 | ||
467 | /** | |
468 | * ntfs_check_logfile - check the journal for consistency | |
469 | * @log_vi: struct inode of loaded journal $LogFile to check | |
470 | * @rp: [OUT] on success this is a copy of the current restart page | |
471 | * | |
472 | * Check the $LogFile journal for consistency and return 'true' if it is | |
473 | * consistent and 'false' if not. On success, the current restart page is | |
474 | * returned in *@rp. Caller must call ntfs_free(*@rp) when finished with it. | |
475 | * | |
476 | * At present we only check the two restart pages and ignore the log record | |
477 | * pages. | |
478 | * | |
479 | * Note that the MstProtected flag is not set on the $LogFile inode and hence | |
480 | * when reading pages they are not deprotected. This is because we do not know | |
481 | * if the $LogFile was created on a system with a different page size to ours | |
482 | * yet and mst deprotection would fail if our page size is smaller. | |
483 | */ | |
484 | bool ntfs_check_logfile(struct inode *log_vi, RESTART_PAGE_HEADER **rp) | |
485 | { | |
486 | s64 size, pos; | |
487 | LSN rstr1_lsn, rstr2_lsn; | |
488 | ntfs_volume *vol = NTFS_SB(log_vi->i_sb); | |
489 | struct address_space *mapping = log_vi->i_mapping; | |
490 | struct page *page = NULL; | |
491 | u8 *kaddr = NULL; | |
492 | RESTART_PAGE_HEADER *rstr1_ph = NULL; | |
493 | RESTART_PAGE_HEADER *rstr2_ph = NULL; | |
494 | int log_page_size, log_page_mask, err; | |
495 | bool logfile_is_empty = true; | |
496 | u8 log_page_bits; | |
497 | ||
498 | ntfs_debug("Entering."); | |
499 | /* An empty $LogFile must have been clean before it got emptied. */ | |
500 | if (NVolLogFileEmpty(vol)) | |
501 | goto is_empty; | |
502 | size = i_size_read(log_vi); | |
503 | /* Make sure the file doesn't exceed the maximum allowed size. */ | |
504 | if (size > MaxLogFileSize) | |
505 | size = MaxLogFileSize; | |
506 | /* | |
507 | * Truncate size to a multiple of the page cache size or the default | |
508 | * log page size if the page cache size is between the default log page | |
509 | * log page size if the page cache size is between the default log page | |
510 | * size and twice that. | |
511 | */ | |
512 | if (PAGE_CACHE_SIZE >= DefaultLogPageSize && PAGE_CACHE_SIZE <= | |
513 | DefaultLogPageSize * 2) | |
514 | log_page_size = DefaultLogPageSize; | |
515 | else | |
516 | log_page_size = PAGE_CACHE_SIZE; | |
517 | log_page_mask = log_page_size - 1; | |
518 | /* | |
519 | * Use ntfs_ffs() instead of ffs() to enable the compiler to | |
520 | * optimize log_page_size and log_page_bits into constants. | |
521 | */ | |
522 | log_page_bits = ntfs_ffs(log_page_size) - 1; | |
523 | size &= ~(s64)(log_page_size - 1); | |
524 | /* | |
525 | * Ensure the log file is big enough to store at least the two restart | |
526 | * pages and the minimum number of log record pages. | |
527 | */ | |
528 | if (size < log_page_size * 2 || (size - log_page_size * 2) >> | |
529 | log_page_bits < MinLogRecordPages) { | |
530 | ntfs_error(vol->sb, "$LogFile is too small."); | |
531 | return false; | |
532 | } | |
533 | /* | |
534 | * Read through the file looking for a restart page. Since the restart | |
535 | * page header is at the beginning of a page we only need to search at | |
536 | * what could be the beginning of a page (for each page size) rather | |
537 | * than scanning the whole file byte by byte. If all potential places | |
538 | * contain empty and uninitialzed records, the log file can be assumed | |
539 | * to be empty. | |
540 | */ | |
541 | for (pos = 0; pos < size; pos <<= 1) { | |
542 | pgoff_t idx = pos >> PAGE_CACHE_SHIFT; | |
543 | if (!page || page->index != idx) { | |
544 | if (page) | |
545 | ntfs_unmap_page(page); | |
546 | page = ntfs_map_page(mapping, idx); | |
547 | if (IS_ERR(page)) { | |
548 | ntfs_error(vol->sb, "Error mapping $LogFile " | |
549 | "page (index %lu).", idx); | |
550 | goto err_out; | |
551 | } | |
552 | } | |
553 | kaddr = (u8*)page_address(page) + (pos & ~PAGE_CACHE_MASK); | |
554 | /* | |
555 | * A non-empty block means the logfile is not empty while an | |
556 | * empty block after a non-empty block has been encountered | |
557 | * means we are done. | |
558 | */ | |
559 | if (!ntfs_is_empty_recordp((le32*)kaddr)) | |
560 | logfile_is_empty = false; | |
561 | else if (!logfile_is_empty) | |
562 | break; | |
563 | /* | |
564 | * A log record page means there cannot be a restart page after | |
565 | * this so no need to continue searching. | |
566 | */ | |
567 | if (ntfs_is_rcrd_recordp((le32*)kaddr)) | |
568 | break; | |
569 | /* If not a (modified by chkdsk) restart page, continue. */ | |
570 | if (!ntfs_is_rstr_recordp((le32*)kaddr) && | |
571 | !ntfs_is_chkd_recordp((le32*)kaddr)) { | |
572 | if (!pos) | |
573 | pos = NTFS_BLOCK_SIZE >> 1; | |
574 | continue; | |
575 | } | |
576 | /* | |
577 | * Check the (modified by chkdsk) restart page for consistency | |
578 | * and get a copy of the complete multi sector transfer | |
579 | * deprotected restart page. | |
580 | */ | |
581 | err = ntfs_check_and_load_restart_page(log_vi, | |
582 | (RESTART_PAGE_HEADER*)kaddr, pos, | |
583 | !rstr1_ph ? &rstr1_ph : &rstr2_ph, | |
584 | !rstr1_ph ? &rstr1_lsn : &rstr2_lsn); | |
585 | if (!err) { | |
586 | /* | |
587 | * If we have now found the first (modified by chkdsk) | |
588 | * restart page, continue looking for the second one. | |
589 | */ | |
590 | if (!pos) { | |
591 | pos = NTFS_BLOCK_SIZE >> 1; | |
592 | continue; | |
593 | } | |
594 | /* | |
595 | * We have now found the second (modified by chkdsk) | |
596 | * restart page, so we can stop looking. | |
597 | */ | |
598 | break; | |
599 | } | |
600 | /* | |
601 | * Error output already done inside the function. Note, we do | |
602 | * not abort if the restart page was invalid as we might still | |
603 | * find a valid one further in the file. | |
604 | */ | |
605 | if (err != -EINVAL) { | |
606 | ntfs_unmap_page(page); | |
607 | goto err_out; | |
608 | } | |
609 | /* Continue looking. */ | |
610 | if (!pos) | |
611 | pos = NTFS_BLOCK_SIZE >> 1; | |
612 | } | |
613 | if (page) | |
614 | ntfs_unmap_page(page); | |
615 | if (logfile_is_empty) { | |
616 | NVolSetLogFileEmpty(vol); | |
617 | is_empty: | |
618 | ntfs_debug("Done. ($LogFile is empty.)"); | |
619 | return true; | |
620 | } | |
621 | if (!rstr1_ph) { | |
622 | BUG_ON(rstr2_ph); | |
623 | ntfs_error(vol->sb, "Did not find any restart pages in " | |
624 | "$LogFile and it was not empty."); | |
625 | return false; | |
626 | } | |
627 | /* If both restart pages were found, use the more recent one. */ | |
628 | if (rstr2_ph) { | |
629 | /* | |
630 | * If the second restart area is more recent, switch to it. | |
631 | * Otherwise just throw it away. | |
632 | */ | |
633 | if (rstr2_lsn > rstr1_lsn) { | |
634 | ntfs_debug("Using second restart page as it is more " | |
635 | "recent."); | |
636 | ntfs_free(rstr1_ph); | |
637 | rstr1_ph = rstr2_ph; | |
638 | /* rstr1_lsn = rstr2_lsn; */ | |
639 | } else { | |
640 | ntfs_debug("Using first restart page as it is more " | |
641 | "recent."); | |
642 | ntfs_free(rstr2_ph); | |
643 | } | |
644 | rstr2_ph = NULL; | |
645 | } | |
646 | /* All consistency checks passed. */ | |
647 | if (rp) | |
648 | *rp = rstr1_ph; | |
649 | else | |
650 | ntfs_free(rstr1_ph); | |
651 | ntfs_debug("Done."); | |
652 | return true; | |
653 | err_out: | |
654 | if (rstr1_ph) | |
655 | ntfs_free(rstr1_ph); | |
656 | return false; | |
657 | } | |
658 | ||
659 | /** | |
660 | * ntfs_is_logfile_clean - check in the journal if the volume is clean | |
661 | * @log_vi: struct inode of loaded journal $LogFile to check | |
662 | * @rp: copy of the current restart page | |
663 | * | |
664 | * Analyze the $LogFile journal and return 'true' if it indicates the volume was | |
665 | * shutdown cleanly and 'false' if not. | |
666 | * | |
667 | * At present we only look at the two restart pages and ignore the log record | |
668 | * pages. This is a little bit crude in that there will be a very small number | |
669 | * of cases where we think that a volume is dirty when in fact it is clean. | |
670 | * This should only affect volumes that have not been shutdown cleanly but did | |
671 | * not have any pending, non-check-pointed i/o, i.e. they were completely idle | |
672 | * at least for the five seconds preceeding the unclean shutdown. | |
673 | * | |
674 | * This function assumes that the $LogFile journal has already been consistency | |
675 | * checked by a call to ntfs_check_logfile() and in particular if the $LogFile | |
676 | * is empty this function requires that NVolLogFileEmpty() is true otherwise an | |
677 | * empty volume will be reported as dirty. | |
678 | */ | |
679 | bool ntfs_is_logfile_clean(struct inode *log_vi, const RESTART_PAGE_HEADER *rp) | |
680 | { | |
681 | ntfs_volume *vol = NTFS_SB(log_vi->i_sb); | |
682 | RESTART_AREA *ra; | |
683 | ||
684 | ntfs_debug("Entering."); | |
685 | /* An empty $LogFile must have been clean before it got emptied. */ | |
686 | if (NVolLogFileEmpty(vol)) { | |
687 | ntfs_debug("Done. ($LogFile is empty.)"); | |
688 | return true; | |
689 | } | |
690 | BUG_ON(!rp); | |
691 | if (!ntfs_is_rstr_record(rp->magic) && | |
692 | !ntfs_is_chkd_record(rp->magic)) { | |
693 | ntfs_error(vol->sb, "Restart page buffer is invalid. This is " | |
694 | "probably a bug in that the $LogFile should " | |
695 | "have been consistency checked before calling " | |
696 | "this function."); | |
697 | return false; | |
698 | } | |
699 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); | |
700 | /* | |
701 | * If the $LogFile has active clients, i.e. it is open, and we do not | |
702 | * have the RESTART_VOLUME_IS_CLEAN bit set in the restart area flags, | |
703 | * we assume there was an unclean shutdown. | |
704 | */ | |
705 | if (ra->client_in_use_list != LOGFILE_NO_CLIENT && | |
706 | !(ra->flags & RESTART_VOLUME_IS_CLEAN)) { | |
707 | ntfs_debug("Done. $LogFile indicates a dirty shutdown."); | |
708 | return false; | |
709 | } | |
710 | /* $LogFile indicates a clean shutdown. */ | |
711 | ntfs_debug("Done. $LogFile indicates a clean shutdown."); | |
712 | return true; | |
713 | } | |
714 | ||
715 | /** | |
716 | * ntfs_empty_logfile - empty the contents of the $LogFile journal | |
717 | * @log_vi: struct inode of loaded journal $LogFile to empty | |
718 | * | |
719 | * Empty the contents of the $LogFile journal @log_vi and return 'true' on | |
720 | * success and 'false' on error. | |
721 | * | |
722 | * This function assumes that the $LogFile journal has already been consistency | |
723 | * checked by a call to ntfs_check_logfile() and that ntfs_is_logfile_clean() | |
724 | * has been used to ensure that the $LogFile is clean. | |
725 | */ | |
726 | bool ntfs_empty_logfile(struct inode *log_vi) | |
727 | { | |
728 | VCN vcn, end_vcn; | |
729 | ntfs_inode *log_ni = NTFS_I(log_vi); | |
730 | ntfs_volume *vol = log_ni->vol; | |
731 | struct super_block *sb = vol->sb; | |
732 | runlist_element *rl; | |
733 | unsigned long flags; | |
734 | unsigned block_size, block_size_bits; | |
735 | int err; | |
736 | bool should_wait = true; | |
737 | ||
738 | ntfs_debug("Entering."); | |
739 | if (NVolLogFileEmpty(vol)) { | |
740 | ntfs_debug("Done."); | |
741 | return true; | |
742 | } | |
743 | /* | |
744 | * We cannot use ntfs_attr_set() because we may be still in the middle | |
745 | * of a mount operation. Thus we do the emptying by hand by first | |
746 | * zapping the page cache pages for the $LogFile/$DATA attribute and | |
747 | * then emptying each of the buffers in each of the clusters specified | |
748 | * by the runlist by hand. | |
749 | */ | |
750 | block_size = sb->s_blocksize; | |
751 | block_size_bits = sb->s_blocksize_bits; | |
752 | vcn = 0; | |
753 | read_lock_irqsave(&log_ni->size_lock, flags); | |
754 | end_vcn = (log_ni->initialized_size + vol->cluster_size_mask) >> | |
755 | vol->cluster_size_bits; | |
756 | read_unlock_irqrestore(&log_ni->size_lock, flags); | |
757 | truncate_inode_pages(log_vi->i_mapping, 0); | |
758 | down_write(&log_ni->runlist.lock); | |
759 | rl = log_ni->runlist.rl; | |
760 | if (unlikely(!rl || vcn < rl->vcn || !rl->length)) { | |
761 | map_vcn: | |
762 | err = ntfs_map_runlist_nolock(log_ni, vcn, NULL); | |
763 | if (err) { | |
764 | ntfs_error(sb, "Failed to map runlist fragment (error " | |
765 | "%d).", -err); | |
766 | goto err; | |
767 | } | |
768 | rl = log_ni->runlist.rl; | |
769 | BUG_ON(!rl || vcn < rl->vcn || !rl->length); | |
770 | } | |
771 | /* Seek to the runlist element containing @vcn. */ | |
772 | while (rl->length && vcn >= rl[1].vcn) | |
773 | rl++; | |
774 | do { | |
775 | LCN lcn; | |
776 | sector_t block, end_block; | |
777 | s64 len; | |
778 | ||
779 | /* | |
780 | * If this run is not mapped map it now and start again as the | |
781 | * runlist will have been updated. | |
782 | */ | |
783 | lcn = rl->lcn; | |
784 | if (unlikely(lcn == LCN_RL_NOT_MAPPED)) { | |
785 | vcn = rl->vcn; | |
786 | goto map_vcn; | |
787 | } | |
788 | /* If this run is not valid abort with an error. */ | |
789 | if (unlikely(!rl->length || lcn < LCN_HOLE)) | |
790 | goto rl_err; | |
791 | /* Skip holes. */ | |
792 | if (lcn == LCN_HOLE) | |
793 | continue; | |
794 | block = lcn << vol->cluster_size_bits >> block_size_bits; | |
795 | len = rl->length; | |
796 | if (rl[1].vcn > end_vcn) | |
797 | len = end_vcn - rl->vcn; | |
798 | end_block = (lcn + len) << vol->cluster_size_bits >> | |
799 | block_size_bits; | |
800 | /* Iterate over the blocks in the run and empty them. */ | |
801 | do { | |
802 | struct buffer_head *bh; | |
803 | ||
804 | /* Obtain the buffer, possibly not uptodate. */ | |
805 | bh = sb_getblk(sb, block); | |
806 | BUG_ON(!bh); | |
807 | /* Setup buffer i/o submission. */ | |
808 | lock_buffer(bh); | |
809 | bh->b_end_io = end_buffer_write_sync; | |
810 | get_bh(bh); | |
811 | /* Set the entire contents of the buffer to 0xff. */ | |
812 | memset(bh->b_data, -1, block_size); | |
813 | if (!buffer_uptodate(bh)) | |
814 | set_buffer_uptodate(bh); | |
815 | if (buffer_dirty(bh)) | |
816 | clear_buffer_dirty(bh); | |
817 | /* | |
818 | * Submit the buffer and wait for i/o to complete but | |
819 | * only for the first buffer so we do not miss really | |
820 | * serious i/o errors. Once the first buffer has | |
821 | * completed ignore errors afterwards as we can assume | |
822 | * that if one buffer worked all of them will work. | |
823 | */ | |
824 | submit_bh(WRITE, bh); | |
825 | if (should_wait) { | |
826 | should_wait = false; | |
827 | wait_on_buffer(bh); | |
828 | if (unlikely(!buffer_uptodate(bh))) | |
829 | goto io_err; | |
830 | } | |
831 | brelse(bh); | |
832 | } while (++block < end_block); | |
833 | } while ((++rl)->vcn < end_vcn); | |
834 | up_write(&log_ni->runlist.lock); | |
835 | /* | |
836 | * Zap the pages again just in case any got instantiated whilst we were | |
837 | * emptying the blocks by hand. FIXME: We may not have completed | |
838 | * writing to all the buffer heads yet so this may happen too early. | |
839 | * We really should use a kernel thread to do the emptying | |
840 | * asynchronously and then we can also set the volume dirty and output | |
841 | * an error message if emptying should fail. | |
842 | */ | |
843 | truncate_inode_pages(log_vi->i_mapping, 0); | |
844 | /* Set the flag so we do not have to do it again on remount. */ | |
845 | NVolSetLogFileEmpty(vol); | |
846 | ntfs_debug("Done."); | |
847 | return true; | |
848 | io_err: | |
849 | ntfs_error(sb, "Failed to write buffer. Unmount and run chkdsk."); | |
850 | goto dirty_err; | |
851 | rl_err: | |
852 | ntfs_error(sb, "Runlist is corrupt. Unmount and run chkdsk."); | |
853 | dirty_err: | |
854 | NVolSetErrors(vol); | |
855 | err = -EIO; | |
856 | err: | |
857 | up_write(&log_ni->runlist.lock); | |
858 | ntfs_error(sb, "Failed to fill $LogFile with 0xff bytes (error %d).", | |
859 | -err); | |
860 | return false; | |
861 | } | |
862 | ||
863 | #endif /* NTFS_RW */ |