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1da177e4 LT |
1 | /* |
2 | * logfile.c - NTFS kernel journal handling. Part of the Linux-NTFS project. | |
3 | * | |
3bd1f4a1 | 4 | * Copyright (c) 2002-2005 Anton Altaparmakov |
1da177e4 LT |
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 | ||
30 | #include "attrib.h" | |
31 | #include "aops.h" | |
32 | #include "debug.h" | |
33 | #include "logfile.h" | |
34 | #include "malloc.h" | |
35 | #include "volume.h" | |
36 | #include "ntfs.h" | |
37 | ||
38 | /** | |
39 | * ntfs_check_restart_page_header - check the page header for consistency | |
40 | * @vi: $LogFile inode to which the restart page header belongs | |
41 | * @rp: restart page header to check | |
42 | * @pos: position in @vi at which the restart page header resides | |
43 | * | |
44 | * Check the restart page header @rp for consistency and return TRUE if it is | |
45 | * consistent and FALSE otherwise. | |
46 | * | |
47 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
48 | * require the full restart page. | |
49 | */ | |
50 | static BOOL ntfs_check_restart_page_header(struct inode *vi, | |
51 | RESTART_PAGE_HEADER *rp, s64 pos) | |
52 | { | |
53 | u32 logfile_system_page_size, logfile_log_page_size; | |
54 | u16 usa_count, usa_ofs, usa_end, ra_ofs; | |
55 | ||
56 | ntfs_debug("Entering."); | |
57 | /* | |
58 | * If the system or log page sizes are smaller than the ntfs block size | |
59 | * or either is not a power of 2 we cannot handle this log file. | |
60 | */ | |
61 | logfile_system_page_size = le32_to_cpu(rp->system_page_size); | |
62 | logfile_log_page_size = le32_to_cpu(rp->log_page_size); | |
63 | if (logfile_system_page_size < NTFS_BLOCK_SIZE || | |
64 | logfile_log_page_size < NTFS_BLOCK_SIZE || | |
65 | logfile_system_page_size & | |
66 | (logfile_system_page_size - 1) || | |
67 | logfile_log_page_size & (logfile_log_page_size - 1)) { | |
68 | ntfs_error(vi->i_sb, "$LogFile uses unsupported page size."); | |
69 | return FALSE; | |
70 | } | |
71 | /* | |
72 | * We must be either at !pos (1st restart page) or at pos = system page | |
73 | * size (2nd restart page). | |
74 | */ | |
75 | if (pos && pos != logfile_system_page_size) { | |
76 | ntfs_error(vi->i_sb, "Found restart area in incorrect " | |
77 | "position in $LogFile."); | |
78 | return FALSE; | |
79 | } | |
80 | /* We only know how to handle version 1.1. */ | |
81 | if (sle16_to_cpu(rp->major_ver) != 1 || | |
82 | sle16_to_cpu(rp->minor_ver) != 1) { | |
83 | ntfs_error(vi->i_sb, "$LogFile version %i.%i is not " | |
84 | "supported. (This driver supports version " | |
85 | "1.1 only.)", (int)sle16_to_cpu(rp->major_ver), | |
86 | (int)sle16_to_cpu(rp->minor_ver)); | |
87 | return FALSE; | |
88 | } | |
89 | /* Verify the size of the update sequence array. */ | |
90 | usa_count = 1 + (logfile_system_page_size >> NTFS_BLOCK_SIZE_BITS); | |
91 | if (usa_count != le16_to_cpu(rp->usa_count)) { | |
92 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
93 | "inconsistent update sequence array count."); | |
94 | return FALSE; | |
95 | } | |
96 | /* Verify the position of the update sequence array. */ | |
97 | usa_ofs = le16_to_cpu(rp->usa_ofs); | |
98 | usa_end = usa_ofs + usa_count * sizeof(u16); | |
99 | if (usa_ofs < sizeof(RESTART_PAGE_HEADER) || | |
100 | usa_end > NTFS_BLOCK_SIZE - sizeof(u16)) { | |
101 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
102 | "inconsistent update sequence array offset."); | |
103 | return FALSE; | |
104 | } | |
105 | /* | |
106 | * Verify the position of the restart area. It must be: | |
107 | * - aligned to 8-byte boundary, | |
108 | * - after the update sequence array, and | |
109 | * - within the system page size. | |
110 | */ | |
111 | ra_ofs = le16_to_cpu(rp->restart_area_offset); | |
112 | if (ra_ofs & 7 || ra_ofs < usa_end || | |
113 | ra_ofs > logfile_system_page_size) { | |
114 | ntfs_error(vi->i_sb, "$LogFile restart page specifies " | |
115 | "inconsistent restart area offset."); | |
116 | return FALSE; | |
117 | } | |
118 | /* | |
119 | * Only restart pages modified by chkdsk are allowed to have chkdsk_lsn | |
120 | * set. | |
121 | */ | |
122 | if (!ntfs_is_chkd_record(rp->magic) && sle64_to_cpu(rp->chkdsk_lsn)) { | |
123 | ntfs_error(vi->i_sb, "$LogFile restart page is not modified " | |
e7a1033b | 124 | "by chkdsk but a chkdsk LSN is specified."); |
1da177e4 LT |
125 | return FALSE; |
126 | } | |
127 | ntfs_debug("Done."); | |
128 | return TRUE; | |
129 | } | |
130 | ||
131 | /** | |
132 | * ntfs_check_restart_area - check the restart area for consistency | |
133 | * @vi: $LogFile inode to which the restart page belongs | |
134 | * @rp: restart page whose restart area to check | |
135 | * | |
136 | * Check the restart area of the restart page @rp for consistency and return | |
137 | * TRUE if it is consistent and FALSE otherwise. | |
138 | * | |
139 | * This function assumes that the restart page header has already been | |
140 | * consistency checked. | |
141 | * | |
142 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
143 | * require the full restart page. | |
144 | */ | |
145 | static BOOL ntfs_check_restart_area(struct inode *vi, RESTART_PAGE_HEADER *rp) | |
146 | { | |
147 | u64 file_size; | |
148 | RESTART_AREA *ra; | |
149 | u16 ra_ofs, ra_len, ca_ofs; | |
150 | u8 fs_bits; | |
151 | ||
152 | ntfs_debug("Entering."); | |
153 | ra_ofs = le16_to_cpu(rp->restart_area_offset); | |
154 | ra = (RESTART_AREA*)((u8*)rp + ra_ofs); | |
155 | /* | |
156 | * Everything before ra->file_size must be before the first word | |
157 | * protected by an update sequence number. This ensures that it is | |
158 | * safe to access ra->client_array_offset. | |
159 | */ | |
160 | if (ra_ofs + offsetof(RESTART_AREA, file_size) > | |
161 | NTFS_BLOCK_SIZE - sizeof(u16)) { | |
162 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
163 | "inconsistent file offset."); | |
164 | return FALSE; | |
165 | } | |
166 | /* | |
167 | * Now that we can access ra->client_array_offset, make sure everything | |
168 | * up to the log client array is before the first word protected by an | |
169 | * update sequence number. This ensures we can access all of the | |
170 | * restart area elements safely. Also, the client array offset must be | |
171 | * aligned to an 8-byte boundary. | |
172 | */ | |
173 | ca_ofs = le16_to_cpu(ra->client_array_offset); | |
174 | if (((ca_ofs + 7) & ~7) != ca_ofs || | |
175 | ra_ofs + ca_ofs > NTFS_BLOCK_SIZE - sizeof(u16)) { | |
176 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
177 | "inconsistent client array offset."); | |
178 | return FALSE; | |
179 | } | |
180 | /* | |
181 | * The restart area must end within the system page size both when | |
182 | * calculated manually and as specified by ra->restart_area_length. | |
183 | * Also, the calculated length must not exceed the specified length. | |
184 | */ | |
185 | ra_len = ca_ofs + le16_to_cpu(ra->log_clients) * | |
186 | sizeof(LOG_CLIENT_RECORD); | |
187 | if (ra_ofs + ra_len > le32_to_cpu(rp->system_page_size) || | |
188 | ra_ofs + le16_to_cpu(ra->restart_area_length) > | |
189 | le32_to_cpu(rp->system_page_size) || | |
190 | ra_len > le16_to_cpu(ra->restart_area_length)) { | |
191 | ntfs_error(vi->i_sb, "$LogFile restart area is out of bounds " | |
192 | "of the system page size specified by the " | |
193 | "restart page header and/or the specified " | |
194 | "restart area length is inconsistent."); | |
195 | return FALSE; | |
196 | } | |
197 | /* | |
198 | * The ra->client_free_list and ra->client_in_use_list must be either | |
199 | * LOGFILE_NO_CLIENT or less than ra->log_clients or they are | |
200 | * overflowing the client array. | |
201 | */ | |
202 | if ((ra->client_free_list != LOGFILE_NO_CLIENT && | |
203 | le16_to_cpu(ra->client_free_list) >= | |
204 | le16_to_cpu(ra->log_clients)) || | |
205 | (ra->client_in_use_list != LOGFILE_NO_CLIENT && | |
206 | le16_to_cpu(ra->client_in_use_list) >= | |
207 | le16_to_cpu(ra->log_clients))) { | |
208 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
209 | "overflowing client free and/or in use lists."); | |
210 | return FALSE; | |
211 | } | |
212 | /* | |
213 | * Check ra->seq_number_bits against ra->file_size for consistency. | |
214 | * We cannot just use ffs() because the file size is not a power of 2. | |
215 | */ | |
216 | file_size = (u64)sle64_to_cpu(ra->file_size); | |
217 | fs_bits = 0; | |
218 | while (file_size) { | |
219 | file_size >>= 1; | |
220 | fs_bits++; | |
221 | } | |
222 | if (le32_to_cpu(ra->seq_number_bits) != 67 - fs_bits) { | |
223 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
224 | "inconsistent sequence number bits."); | |
225 | return FALSE; | |
226 | } | |
227 | /* The log record header length must be a multiple of 8. */ | |
228 | if (((le16_to_cpu(ra->log_record_header_length) + 7) & ~7) != | |
229 | le16_to_cpu(ra->log_record_header_length)) { | |
230 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
231 | "inconsistent log record header length."); | |
232 | return FALSE; | |
233 | } | |
234 | /* Dito for the log page data offset. */ | |
235 | if (((le16_to_cpu(ra->log_page_data_offset) + 7) & ~7) != | |
236 | le16_to_cpu(ra->log_page_data_offset)) { | |
237 | ntfs_error(vi->i_sb, "$LogFile restart area specifies " | |
238 | "inconsistent log page data offset."); | |
239 | return FALSE; | |
240 | } | |
241 | ntfs_debug("Done."); | |
242 | return TRUE; | |
243 | } | |
244 | ||
245 | /** | |
246 | * ntfs_check_log_client_array - check the log client array for consistency | |
247 | * @vi: $LogFile inode to which the restart page belongs | |
248 | * @rp: restart page whose log client array to check | |
249 | * | |
250 | * Check the log client array of the restart page @rp for consistency and | |
251 | * return TRUE if it is consistent and FALSE otherwise. | |
252 | * | |
253 | * This function assumes that the restart page header and the restart area have | |
254 | * already been consistency checked. | |
255 | * | |
256 | * Unlike ntfs_check_restart_page_header() and ntfs_check_restart_area(), this | |
257 | * function needs @rp->system_page_size bytes in @rp, i.e. it requires the full | |
258 | * restart page and the page must be multi sector transfer deprotected. | |
259 | */ | |
260 | static BOOL ntfs_check_log_client_array(struct inode *vi, | |
261 | RESTART_PAGE_HEADER *rp) | |
262 | { | |
263 | RESTART_AREA *ra; | |
264 | LOG_CLIENT_RECORD *ca, *cr; | |
265 | u16 nr_clients, idx; | |
266 | BOOL in_free_list, idx_is_first; | |
267 | ||
268 | ntfs_debug("Entering."); | |
269 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); | |
270 | ca = (LOG_CLIENT_RECORD*)((u8*)ra + | |
271 | le16_to_cpu(ra->client_array_offset)); | |
272 | /* | |
273 | * Check the ra->client_free_list first and then check the | |
274 | * ra->client_in_use_list. Check each of the log client records in | |
275 | * each of the lists and check that the array does not overflow the | |
276 | * ra->log_clients value. Also keep track of the number of records | |
277 | * visited as there cannot be more than ra->log_clients records and | |
278 | * that way we detect eventual loops in within a list. | |
279 | */ | |
280 | nr_clients = le16_to_cpu(ra->log_clients); | |
281 | idx = le16_to_cpu(ra->client_free_list); | |
282 | in_free_list = TRUE; | |
283 | check_list: | |
284 | for (idx_is_first = TRUE; idx != LOGFILE_NO_CLIENT_CPU; nr_clients--, | |
285 | idx = le16_to_cpu(cr->next_client)) { | |
286 | if (!nr_clients || idx >= le16_to_cpu(ra->log_clients)) | |
287 | goto err_out; | |
288 | /* Set @cr to the current log client record. */ | |
289 | cr = ca + idx; | |
290 | /* The first log client record must not have a prev_client. */ | |
291 | if (idx_is_first) { | |
292 | if (cr->prev_client != LOGFILE_NO_CLIENT) | |
293 | goto err_out; | |
294 | idx_is_first = FALSE; | |
295 | } | |
296 | } | |
297 | /* Switch to and check the in use list if we just did the free list. */ | |
298 | if (in_free_list) { | |
299 | in_free_list = FALSE; | |
300 | idx = le16_to_cpu(ra->client_in_use_list); | |
301 | goto check_list; | |
302 | } | |
303 | ntfs_debug("Done."); | |
304 | return TRUE; | |
305 | err_out: | |
306 | ntfs_error(vi->i_sb, "$LogFile log client array is corrupt."); | |
307 | return FALSE; | |
308 | } | |
309 | ||
310 | /** | |
311 | * ntfs_check_and_load_restart_page - check the restart page for consistency | |
312 | * @vi: $LogFile inode to which the restart page belongs | |
313 | * @rp: restart page to check | |
314 | * @pos: position in @vi at which the restart page resides | |
e7a1033b AA |
315 | * @wrp: [OUT] copy of the multi sector transfer deprotected restart page |
316 | * @lsn: [OUT] set to the current logfile lsn on success | |
1da177e4 | 317 | * |
e7a1033b AA |
318 | * Check the restart page @rp for consistency and return 0 if it is consistent |
319 | * and -errno otherwise. The restart page may have been modified by chkdsk in | |
320 | * which case its magic is CHKD instead of RSTR. | |
1da177e4 LT |
321 | * |
322 | * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not | |
323 | * require the full restart page. | |
324 | * | |
325 | * If @wrp is not NULL, on success, *@wrp will point to a buffer containing a | |
326 | * copy of the complete multi sector transfer deprotected page. On failure, | |
327 | * *@wrp is undefined. | |
e7a1033b AA |
328 | * |
329 | * Simillarly, if @lsn is not NULL, on succes *@lsn will be set to the current | |
330 | * logfile lsn according to this restart page. On failure, *@lsn is undefined. | |
331 | * | |
332 | * The following error codes are defined: | |
333 | * -EINVAL - The restart page is inconsistent. | |
334 | * -ENOMEM - Not enough memory to load the restart page. | |
335 | * -EIO - Failed to reading from $LogFile. | |
1da177e4 | 336 | */ |
e7a1033b AA |
337 | static int ntfs_check_and_load_restart_page(struct inode *vi, |
338 | RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp, | |
339 | LSN *lsn) | |
1da177e4 LT |
340 | { |
341 | RESTART_AREA *ra; | |
342 | RESTART_PAGE_HEADER *trp; | |
e7a1033b | 343 | int size, err; |
1da177e4 LT |
344 | |
345 | ntfs_debug("Entering."); | |
346 | /* Check the restart page header for consistency. */ | |
347 | if (!ntfs_check_restart_page_header(vi, rp, pos)) { | |
348 | /* Error output already done inside the function. */ | |
e7a1033b | 349 | return -EINVAL; |
1da177e4 LT |
350 | } |
351 | /* Check the restart area for consistency. */ | |
352 | if (!ntfs_check_restart_area(vi, rp)) { | |
353 | /* Error output already done inside the function. */ | |
e7a1033b | 354 | return -EINVAL; |
1da177e4 LT |
355 | } |
356 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); | |
357 | /* | |
358 | * Allocate a buffer to store the whole restart page so we can multi | |
359 | * sector transfer deprotect it. | |
360 | */ | |
361 | trp = ntfs_malloc_nofs(le32_to_cpu(rp->system_page_size)); | |
362 | if (!trp) { | |
363 | ntfs_error(vi->i_sb, "Failed to allocate memory for $LogFile " | |
364 | "restart page buffer."); | |
e7a1033b | 365 | return -ENOMEM; |
1da177e4 LT |
366 | } |
367 | /* | |
368 | * Read the whole of the restart page into the buffer. If it fits | |
369 | * completely inside @rp, just copy it from there. Otherwise map all | |
370 | * the required pages and copy the data from them. | |
371 | */ | |
372 | size = PAGE_CACHE_SIZE - (pos & ~PAGE_CACHE_MASK); | |
373 | if (size >= le32_to_cpu(rp->system_page_size)) { | |
374 | memcpy(trp, rp, le32_to_cpu(rp->system_page_size)); | |
375 | } else { | |
376 | pgoff_t idx; | |
377 | struct page *page; | |
378 | int have_read, to_read; | |
379 | ||
380 | /* First copy what we already have in @rp. */ | |
381 | memcpy(trp, rp, size); | |
382 | /* Copy the remaining data one page at a time. */ | |
383 | have_read = size; | |
384 | to_read = le32_to_cpu(rp->system_page_size) - size; | |
385 | idx = (pos + size) >> PAGE_CACHE_SHIFT; | |
386 | BUG_ON((pos + size) & ~PAGE_CACHE_MASK); | |
387 | do { | |
388 | page = ntfs_map_page(vi->i_mapping, idx); | |
389 | if (IS_ERR(page)) { | |
390 | ntfs_error(vi->i_sb, "Error mapping $LogFile " | |
391 | "page (index %lu).", idx); | |
e7a1033b AA |
392 | err = PTR_ERR(page); |
393 | if (err != -EIO && err != -ENOMEM) | |
394 | err = -EIO; | |
1da177e4 LT |
395 | goto err_out; |
396 | } | |
397 | size = min_t(int, to_read, PAGE_CACHE_SIZE); | |
398 | memcpy((u8*)trp + have_read, page_address(page), size); | |
399 | ntfs_unmap_page(page); | |
400 | have_read += size; | |
401 | to_read -= size; | |
402 | idx++; | |
403 | } while (to_read > 0); | |
404 | } | |
405 | /* Perform the multi sector transfer deprotection on the buffer. */ | |
406 | if (post_read_mst_fixup((NTFS_RECORD*)trp, | |
407 | le32_to_cpu(rp->system_page_size))) { | |
e7a1033b AA |
408 | /* |
409 | * A multi sector tranfer error was detected. We only need to | |
410 | * abort if the restart page contents exceed the multi sector | |
411 | * transfer fixup of the first sector. | |
412 | */ | |
413 | if (le16_to_cpu(rp->restart_area_offset) + | |
414 | le16_to_cpu(ra->restart_area_length) > | |
415 | NTFS_BLOCK_SIZE - sizeof(u16)) { | |
416 | ntfs_error(vi->i_sb, "Multi sector transfer error " | |
417 | "detected in $LogFile restart page."); | |
418 | err = -EINVAL; | |
419 | goto err_out; | |
420 | } | |
421 | } | |
422 | /* | |
423 | * If the restart page is modified by chkdsk or there are no active | |
424 | * logfile clients, the logfile is consistent. Otherwise, need to | |
425 | * check the log client records for consistency, too. | |
426 | */ | |
427 | err = 0; | |
428 | if (ntfs_is_rstr_record(rp->magic) && | |
429 | ra->client_in_use_list != LOGFILE_NO_CLIENT) { | |
430 | if (!ntfs_check_log_client_array(vi, trp)) { | |
431 | err = -EINVAL; | |
432 | goto err_out; | |
433 | } | |
434 | } | |
435 | if (lsn) { | |
436 | if (ntfs_is_rstr_record(rp->magic)) | |
437 | *lsn = sle64_to_cpu(ra->current_lsn); | |
438 | else /* if (ntfs_is_chkd_record(rp->magic)) */ | |
439 | *lsn = sle64_to_cpu(rp->chkdsk_lsn); | |
1da177e4 | 440 | } |
1da177e4 | 441 | ntfs_debug("Done."); |
e7a1033b AA |
442 | if (wrp) |
443 | *wrp = trp; | |
444 | else { | |
1da177e4 | 445 | err_out: |
e7a1033b AA |
446 | ntfs_free(trp); |
447 | } | |
448 | return err; | |
1da177e4 LT |
449 | } |
450 | ||
451 | /** | |
3bd1f4a1 | 452 | * ntfs_check_logfile - check the journal for consistency |
1da177e4 | 453 | * @log_vi: struct inode of loaded journal $LogFile to check |
e7a1033b | 454 | * @rp: [OUT] on success this is a copy of the current restart page |
1da177e4 LT |
455 | * |
456 | * Check the $LogFile journal for consistency and return TRUE if it is | |
e7a1033b AA |
457 | * consistent and FALSE if not. On success, the current restart page is |
458 | * returned in *@rp. Caller must call ntfs_free(*@rp) when finished with it. | |
1da177e4 LT |
459 | * |
460 | * At present we only check the two restart pages and ignore the log record | |
461 | * pages. | |
462 | * | |
463 | * Note that the MstProtected flag is not set on the $LogFile inode and hence | |
464 | * when reading pages they are not deprotected. This is because we do not know | |
465 | * if the $LogFile was created on a system with a different page size to ours | |
466 | * yet and mst deprotection would fail if our page size is smaller. | |
467 | */ | |
e7a1033b | 468 | BOOL ntfs_check_logfile(struct inode *log_vi, RESTART_PAGE_HEADER **rp) |
1da177e4 | 469 | { |
e7a1033b AA |
470 | s64 size, pos; |
471 | LSN rstr1_lsn, rstr2_lsn; | |
1da177e4 LT |
472 | ntfs_volume *vol = NTFS_SB(log_vi->i_sb); |
473 | struct address_space *mapping = log_vi->i_mapping; | |
474 | struct page *page = NULL; | |
475 | u8 *kaddr = NULL; | |
476 | RESTART_PAGE_HEADER *rstr1_ph = NULL; | |
477 | RESTART_PAGE_HEADER *rstr2_ph = NULL; | |
e7a1033b | 478 | int log_page_size, log_page_mask, err; |
1da177e4 | 479 | BOOL logfile_is_empty = TRUE; |
1da177e4 LT |
480 | u8 log_page_bits; |
481 | ||
482 | ntfs_debug("Entering."); | |
483 | /* An empty $LogFile must have been clean before it got emptied. */ | |
484 | if (NVolLogFileEmpty(vol)) | |
485 | goto is_empty; | |
66129f88 | 486 | size = i_size_read(log_vi); |
1da177e4 LT |
487 | /* Make sure the file doesn't exceed the maximum allowed size. */ |
488 | if (size > MaxLogFileSize) | |
489 | size = MaxLogFileSize; | |
490 | /* | |
491 | * Truncate size to a multiple of the page cache size or the default | |
492 | * log page size if the page cache size is between the default log page | |
493 | * log page size if the page cache size is between the default log page | |
494 | * size and twice that. | |
495 | */ | |
496 | if (PAGE_CACHE_SIZE >= DefaultLogPageSize && PAGE_CACHE_SIZE <= | |
497 | DefaultLogPageSize * 2) | |
498 | log_page_size = DefaultLogPageSize; | |
499 | else | |
500 | log_page_size = PAGE_CACHE_SIZE; | |
501 | log_page_mask = log_page_size - 1; | |
502 | /* | |
503 | * Use generic_ffs() instead of ffs() to enable the compiler to | |
504 | * optimize log_page_size and log_page_bits into constants. | |
505 | */ | |
506 | log_page_bits = generic_ffs(log_page_size) - 1; | |
3bd1f4a1 | 507 | size &= ~(s64)(log_page_size - 1); |
1da177e4 LT |
508 | /* |
509 | * Ensure the log file is big enough to store at least the two restart | |
510 | * pages and the minimum number of log record pages. | |
511 | */ | |
512 | if (size < log_page_size * 2 || (size - log_page_size * 2) >> | |
513 | log_page_bits < MinLogRecordPages) { | |
514 | ntfs_error(vol->sb, "$LogFile is too small."); | |
515 | return FALSE; | |
516 | } | |
517 | /* | |
518 | * Read through the file looking for a restart page. Since the restart | |
519 | * page header is at the beginning of a page we only need to search at | |
520 | * what could be the beginning of a page (for each page size) rather | |
521 | * than scanning the whole file byte by byte. If all potential places | |
522 | * contain empty and uninitialzed records, the log file can be assumed | |
523 | * to be empty. | |
524 | */ | |
525 | for (pos = 0; pos < size; pos <<= 1) { | |
526 | pgoff_t idx = pos >> PAGE_CACHE_SHIFT; | |
527 | if (!page || page->index != idx) { | |
528 | if (page) | |
529 | ntfs_unmap_page(page); | |
530 | page = ntfs_map_page(mapping, idx); | |
531 | if (IS_ERR(page)) { | |
532 | ntfs_error(vol->sb, "Error mapping $LogFile " | |
533 | "page (index %lu).", idx); | |
e7a1033b | 534 | goto err_out; |
1da177e4 LT |
535 | } |
536 | } | |
537 | kaddr = (u8*)page_address(page) + (pos & ~PAGE_CACHE_MASK); | |
538 | /* | |
539 | * A non-empty block means the logfile is not empty while an | |
540 | * empty block after a non-empty block has been encountered | |
541 | * means we are done. | |
542 | */ | |
543 | if (!ntfs_is_empty_recordp((le32*)kaddr)) | |
544 | logfile_is_empty = FALSE; | |
545 | else if (!logfile_is_empty) | |
546 | break; | |
547 | /* | |
548 | * A log record page means there cannot be a restart page after | |
549 | * this so no need to continue searching. | |
550 | */ | |
551 | if (ntfs_is_rcrd_recordp((le32*)kaddr)) | |
552 | break; | |
e7a1033b AA |
553 | /* If not a (modified by chkdsk) restart page, continue. */ |
554 | if (!ntfs_is_rstr_recordp((le32*)kaddr) && | |
555 | !ntfs_is_chkd_recordp((le32*)kaddr)) { | |
1da177e4 LT |
556 | if (!pos) |
557 | pos = NTFS_BLOCK_SIZE >> 1; | |
558 | continue; | |
559 | } | |
1da177e4 | 560 | /* |
e7a1033b AA |
561 | * Check the (modified by chkdsk) restart page for consistency |
562 | * and get a copy of the complete multi sector transfer | |
563 | * deprotected restart page. | |
1da177e4 | 564 | */ |
e7a1033b | 565 | err = ntfs_check_and_load_restart_page(log_vi, |
1da177e4 | 566 | (RESTART_PAGE_HEADER*)kaddr, pos, |
e7a1033b AA |
567 | !rstr1_ph ? &rstr1_ph : &rstr2_ph, |
568 | !rstr1_ph ? &rstr1_lsn : &rstr2_lsn); | |
569 | if (!err) { | |
570 | /* | |
571 | * If we have now found the first (modified by chkdsk) | |
572 | * restart page, continue looking for the second one. | |
573 | */ | |
574 | if (!pos) { | |
575 | pos = NTFS_BLOCK_SIZE >> 1; | |
576 | continue; | |
577 | } | |
578 | /* | |
579 | * We have now found the second (modified by chkdsk) | |
580 | * restart page, so we can stop looking. | |
581 | */ | |
582 | break; | |
1da177e4 LT |
583 | } |
584 | /* | |
e7a1033b AA |
585 | * Error output already done inside the function. Note, we do |
586 | * not abort if the restart page was invalid as we might still | |
587 | * find a valid one further in the file. | |
1da177e4 | 588 | */ |
e7a1033b AA |
589 | if (err != -EINVAL) { |
590 | ntfs_unmap_page(page); | |
591 | goto err_out; | |
592 | } | |
593 | /* Continue looking. */ | |
1da177e4 | 594 | if (!pos) |
e7a1033b | 595 | pos = NTFS_BLOCK_SIZE >> 1; |
1da177e4 | 596 | } |
e7a1033b | 597 | if (page) |
1da177e4 | 598 | ntfs_unmap_page(page); |
1da177e4 LT |
599 | if (logfile_is_empty) { |
600 | NVolSetLogFileEmpty(vol); | |
601 | is_empty: | |
602 | ntfs_debug("Done. ($LogFile is empty.)"); | |
603 | return TRUE; | |
604 | } | |
e7a1033b AA |
605 | if (!rstr1_ph) { |
606 | BUG_ON(rstr2_ph); | |
607 | ntfs_error(vol->sb, "Did not find any restart pages in " | |
608 | "$LogFile and it was not empty."); | |
609 | return FALSE; | |
610 | } | |
611 | /* If both restart pages were found, use the more recent one. */ | |
612 | if (rstr2_ph) { | |
613 | /* | |
614 | * If the second restart area is more recent, switch to it. | |
615 | * Otherwise just throw it away. | |
616 | */ | |
617 | if (rstr2_lsn > rstr1_lsn) { | |
618 | ntfs_free(rstr1_ph); | |
619 | rstr1_ph = rstr2_ph; | |
620 | /* rstr1_lsn = rstr2_lsn; */ | |
621 | } else | |
622 | ntfs_free(rstr2_ph); | |
623 | rstr2_ph = NULL; | |
1da177e4 | 624 | } |
1da177e4 | 625 | /* All consistency checks passed. */ |
e7a1033b AA |
626 | if (rp) |
627 | *rp = rstr1_ph; | |
628 | else | |
629 | ntfs_free(rstr1_ph); | |
1da177e4 LT |
630 | ntfs_debug("Done."); |
631 | return TRUE; | |
632 | err_out: | |
1da177e4 LT |
633 | if (rstr1_ph) |
634 | ntfs_free(rstr1_ph); | |
1da177e4 LT |
635 | return FALSE; |
636 | } | |
637 | ||
638 | /** | |
639 | * ntfs_is_logfile_clean - check in the journal if the volume is clean | |
640 | * @log_vi: struct inode of loaded journal $LogFile to check | |
e7a1033b | 641 | * @rp: copy of the current restart page |
1da177e4 LT |
642 | * |
643 | * Analyze the $LogFile journal and return TRUE if it indicates the volume was | |
644 | * shutdown cleanly and FALSE if not. | |
645 | * | |
646 | * At present we only look at the two restart pages and ignore the log record | |
647 | * pages. This is a little bit crude in that there will be a very small number | |
648 | * of cases where we think that a volume is dirty when in fact it is clean. | |
649 | * This should only affect volumes that have not been shutdown cleanly but did | |
650 | * not have any pending, non-check-pointed i/o, i.e. they were completely idle | |
651 | * at least for the five seconds preceeding the unclean shutdown. | |
652 | * | |
653 | * This function assumes that the $LogFile journal has already been consistency | |
654 | * checked by a call to ntfs_check_logfile() and in particular if the $LogFile | |
655 | * is empty this function requires that NVolLogFileEmpty() is true otherwise an | |
656 | * empty volume will be reported as dirty. | |
657 | */ | |
e7a1033b | 658 | BOOL ntfs_is_logfile_clean(struct inode *log_vi, const RESTART_PAGE_HEADER *rp) |
1da177e4 LT |
659 | { |
660 | ntfs_volume *vol = NTFS_SB(log_vi->i_sb); | |
1da177e4 LT |
661 | RESTART_AREA *ra; |
662 | ||
663 | ntfs_debug("Entering."); | |
664 | /* An empty $LogFile must have been clean before it got emptied. */ | |
665 | if (NVolLogFileEmpty(vol)) { | |
666 | ntfs_debug("Done. ($LogFile is empty.)"); | |
667 | return TRUE; | |
668 | } | |
e7a1033b AA |
669 | BUG_ON(!rp); |
670 | if (!ntfs_is_rstr_record(rp->magic) && | |
671 | !ntfs_is_chkd_record(rp->magic)) { | |
672 | ntfs_error(vol->sb, "Restart page buffer is invalid. This is " | |
673 | "probably a bug in that the $LogFile should " | |
674 | "have been consistency checked before calling " | |
675 | "this function."); | |
1da177e4 LT |
676 | return FALSE; |
677 | } | |
1da177e4 LT |
678 | ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); |
679 | /* | |
680 | * If the $LogFile has active clients, i.e. it is open, and we do not | |
681 | * have the RESTART_VOLUME_IS_CLEAN bit set in the restart area flags, | |
682 | * we assume there was an unclean shutdown. | |
683 | */ | |
684 | if (ra->client_in_use_list != LOGFILE_NO_CLIENT && | |
685 | !(ra->flags & RESTART_VOLUME_IS_CLEAN)) { | |
686 | ntfs_debug("Done. $LogFile indicates a dirty shutdown."); | |
e7a1033b | 687 | return FALSE; |
1da177e4 | 688 | } |
1da177e4 LT |
689 | /* $LogFile indicates a clean shutdown. */ |
690 | ntfs_debug("Done. $LogFile indicates a clean shutdown."); | |
691 | return TRUE; | |
1da177e4 LT |
692 | } |
693 | ||
694 | /** | |
695 | * ntfs_empty_logfile - empty the contents of the $LogFile journal | |
696 | * @log_vi: struct inode of loaded journal $LogFile to empty | |
697 | * | |
698 | * Empty the contents of the $LogFile journal @log_vi and return TRUE on | |
699 | * success and FALSE on error. | |
700 | * | |
701 | * This function assumes that the $LogFile journal has already been consistency | |
702 | * checked by a call to ntfs_check_logfile() and that ntfs_is_logfile_clean() | |
703 | * has been used to ensure that the $LogFile is clean. | |
704 | */ | |
705 | BOOL ntfs_empty_logfile(struct inode *log_vi) | |
706 | { | |
707 | ntfs_volume *vol = NTFS_SB(log_vi->i_sb); | |
708 | ||
709 | ntfs_debug("Entering."); | |
710 | if (!NVolLogFileEmpty(vol)) { | |
711 | int err; | |
712 | ||
66129f88 AA |
713 | err = ntfs_attr_set(NTFS_I(log_vi), 0, i_size_read(log_vi), |
714 | 0xff); | |
1da177e4 LT |
715 | if (unlikely(err)) { |
716 | ntfs_error(vol->sb, "Failed to fill $LogFile with " | |
717 | "0xff bytes (error code %i).", err); | |
718 | return FALSE; | |
719 | } | |
720 | /* Set the flag so we do not have to do it again on remount. */ | |
721 | NVolSetLogFileEmpty(vol); | |
722 | } | |
723 | ntfs_debug("Done."); | |
724 | return TRUE; | |
725 | } | |
726 | ||
727 | #endif /* NTFS_RW */ |