]>
git.ipfire.org Git - thirdparty/mdadm.git/blob - raid6check.c
2 * raid6check - extended consistency check for RAID-6
4 * Copyright (C) 2011 Piergiorgio Sartor
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 * Author: Piergiorgio Sartor
22 * Based on "restripe.c" from "mdadm" codebase
30 int geo_map(int block
, unsigned long long stripe
, int raid_disks
,
31 int level
, int layout
);
32 void qsyndrome(uint8_t *p
, uint8_t *q
, uint8_t **sources
, int disks
, int size
);
33 void make_tables(void);
34 void ensure_zero_has_size(int chunk_size
);
35 void raid6_datap_recov(int disks
, size_t bytes
, int faila
, uint8_t **ptrs
);
36 void raid6_2data_recov(int disks
, size_t bytes
, int faila
, int failb
,
38 void xor_blocks(char *target
, char **sources
, int disks
, int size
);
41 /* Collect per stripe consistency information */
42 void raid6_collect(int chunk_size
, uint8_t *p
, uint8_t *q
,
43 char *chunkP
, char *chunkQ
, int *results
)
48 extern uint8_t raid6_gflog
[];
50 for(i
= 0; i
< chunk_size
; i
++) {
51 Px
= (uint8_t)chunkP
[i
] ^ (uint8_t)p
[i
];
52 Qx
= (uint8_t)chunkQ
[i
] ^ (uint8_t)q
[i
];
54 if((Px
!= 0) && (Qx
== 0))
57 if((Px
== 0) && (Qx
!= 0))
60 if((Px
!= 0) && (Qx
!= 0)) {
61 data_id
= (raid6_gflog
[Qx
] - raid6_gflog
[Px
]);
62 if(data_id
< 0) data_id
+= 255;
66 if((Px
== 0) && (Qx
== 0))
71 /* Try to find out if a specific disk has problems */
72 int raid6_stats(int *results
, int raid_disks
, int chunk_size
)
75 int curr_broken_disk
= -255;
76 int prev_broken_disk
= -255;
77 int broken_status
= 0;
79 for(i
= 0; i
< chunk_size
; i
++) {
81 if(results
[i
] != -255)
82 curr_broken_disk
= results
[i
];
84 if(curr_broken_disk
>= raid_disks
)
87 switch(broken_status
) {
89 if(curr_broken_disk
!= -255) {
90 prev_broken_disk
= curr_broken_disk
;
96 if(curr_broken_disk
!= prev_broken_disk
)
102 curr_broken_disk
= prev_broken_disk
= -65535;
107 return curr_broken_disk
;
110 int check_stripes(struct mdinfo
*info
, int *source
, unsigned long long *offsets
,
111 int raid_disks
, int chunk_size
, int level
, int layout
,
112 unsigned long long start
, unsigned long long length
, char *name
[],
113 int repair
, int failed_disk1
, int failed_disk2
)
115 /* read the data and p and q blocks, and check we got them right */
116 char *stripe_buf
= xmalloc(raid_disks
* chunk_size
);
117 char **stripes
= xmalloc(raid_disks
* sizeof(char*));
118 char **blocks
= xmalloc(raid_disks
* sizeof(char*));
119 uint8_t *p
= xmalloc(chunk_size
);
120 uint8_t *q
= xmalloc(chunk_size
);
121 int *results
= xmalloc(chunk_size
* sizeof(int));
125 int data_disks
= raid_disks
- 2;
130 extern int tables_ready
;
135 for ( i
= 0 ; i
< raid_disks
; i
++)
136 stripes
[i
] = stripe_buf
+ i
* chunk_size
;
141 printf("pos --> %llu\n", start
);
143 if(mlockall(MCL_CURRENT
| MCL_FUTURE
) != 0) {
147 sig
[0] = signal(SIGTERM
, SIG_IGN
);
148 sig
[1] = signal(SIGINT
, SIG_IGN
);
149 sig
[2] = signal(SIGQUIT
, SIG_IGN
);
150 rv
= sysfs_set_num(info
, NULL
, "suspend_lo", start
* chunk_size
* data_disks
);
151 rv
|= sysfs_set_num(info
, NULL
, "suspend_hi", (start
+ 1) * chunk_size
* data_disks
);
152 for (i
= 0 ; i
< raid_disks
; i
++) {
153 lseek64(source
[i
], offsets
[i
] + start
* chunk_size
, 0);
154 read(source
[i
], stripes
[i
], chunk_size
);
156 rv
|= sysfs_set_num(info
, NULL
, "suspend_lo", 0x7FFFFFFFFFFFFFFFULL
);
157 rv
|= sysfs_set_num(info
, NULL
, "suspend_hi", 0);
158 rv
|= sysfs_set_num(info
, NULL
, "suspend_lo", 0);
159 signal(SIGQUIT
, sig
[2]);
160 signal(SIGINT
, sig
[1]);
161 signal(SIGTERM
, sig
[0]);
162 if(munlockall() != 0) {
172 for (i
= 0 ; i
< data_disks
; i
++) {
173 int disk
= geo_map(i
, start
, raid_disks
, level
, layout
);
174 blocks
[i
] = stripes
[disk
];
175 printf("%d->%d\n", i
, disk
);
178 qsyndrome(p
, q
, (uint8_t**)blocks
, data_disks
, chunk_size
);
179 diskP
= geo_map(-1, start
, raid_disks
, level
, layout
);
180 diskQ
= geo_map(-2, start
, raid_disks
, level
, layout
);
181 blocks
[data_disks
] = stripes
[diskP
];
182 blocks
[data_disks
+1] = stripes
[diskQ
];
184 if (memcmp(p
, stripes
[diskP
], chunk_size
) != 0) {
185 printf("P(%d) wrong at %llu\n", diskP
, start
);
187 if (memcmp(q
, stripes
[diskQ
], chunk_size
) != 0) {
188 printf("Q(%d) wrong at %llu\n", diskQ
, start
);
190 raid6_collect(chunk_size
, p
, q
, stripes
[diskP
], stripes
[diskQ
], results
);
191 disk
= raid6_stats(results
, raid_disks
, chunk_size
);
194 disk
= geo_map(disk
, start
, raid_disks
, level
, layout
);
197 printf("Error detected at %llu: possible failed disk slot: %d --> %s\n",
198 start
, disk
, name
[disk
]);
201 printf("Error detected at %llu: disk slot unknown\n", start
);
204 printf("Repairing stripe %llu\n", start
);
205 printf("Assuming slots %d (%s) and %d (%s) are incorrect\n",
206 failed_disk1
, name
[failed_disk1
],
207 failed_disk2
, name
[failed_disk2
]);
209 if (failed_disk1
== diskQ
|| failed_disk2
== diskQ
) {
210 char *all_but_failed_blocks
[data_disks
];
212 int failed_block_index
;
214 if (failed_disk1
== diskQ
)
215 failed_data
= failed_disk2
;
217 failed_data
= failed_disk1
;
218 printf("Repairing D/P(%d) and Q\n", failed_data
);
219 failed_block_index
= geo_map(
220 failed_data
, start
, raid_disks
,
222 for (i
=0; i
< data_disks
; i
++)
223 if (failed_block_index
== i
)
224 all_but_failed_blocks
[i
] = stripes
[diskP
];
226 all_but_failed_blocks
[i
] = blocks
[i
];
227 xor_blocks(stripes
[failed_data
],
228 all_but_failed_blocks
, data_disks
, chunk_size
);
229 qsyndrome(p
, (uint8_t*)stripes
[diskQ
], (uint8_t**)blocks
, data_disks
, chunk_size
);
231 ensure_zero_has_size(chunk_size
);
232 if (failed_disk1
== diskP
|| failed_disk2
== diskP
) {
233 int failed_data
, failed_block_index
;
234 if (failed_disk1
== diskP
)
235 failed_data
= failed_disk2
;
237 failed_data
= failed_disk1
;
238 failed_block_index
= geo_map(failed_data
, start
, raid_disks
, level
, layout
);
239 printf("Repairing D(%d) and P\n", failed_data
);
240 raid6_datap_recov(raid_disks
, chunk_size
, failed_block_index
, (uint8_t**)blocks
);
242 printf("Repairing D and D\n");
243 int failed_block_index1
= geo_map(failed_disk1
, start
, raid_disks
, level
, layout
);
244 int failed_block_index2
= geo_map(failed_disk2
, start
, raid_disks
, level
, layout
);
245 if (failed_block_index1
> failed_block_index2
) {
246 int t
= failed_block_index1
;
247 failed_block_index1
= failed_block_index2
;
248 failed_block_index2
= t
;
250 raid6_2data_recov(raid_disks
, chunk_size
, failed_block_index1
, failed_block_index2
, (uint8_t**)blocks
);
253 if(mlockall(MCL_CURRENT
| MCL_FUTURE
) != 0) {
257 sig
[0] = signal(SIGTERM
, SIG_IGN
);
258 sig
[1] = signal(SIGINT
, SIG_IGN
);
259 sig
[2] = signal(SIGQUIT
, SIG_IGN
);
260 rv
= sysfs_set_num(info
, NULL
, "suspend_lo", start
* chunk_size
* data_disks
);
261 rv
|= sysfs_set_num(info
, NULL
, "suspend_hi", (start
+ 1) * chunk_size
* data_disks
);
262 lseek64(source
[failed_disk1
], offsets
[failed_disk1
] + start
* chunk_size
, 0);
263 write(source
[failed_disk1
], stripes
[failed_disk1
], chunk_size
);
264 lseek64(source
[failed_disk2
], offsets
[failed_disk2
] + start
* chunk_size
, 0);
265 write(source
[failed_disk2
], stripes
[failed_disk2
], chunk_size
);
266 rv
|= sysfs_set_num(info
, NULL
, "suspend_lo", 0x7FFFFFFFFFFFFFFFULL
);
267 rv
|= sysfs_set_num(info
, NULL
, "suspend_hi", 0);
268 rv
|= sysfs_set_num(info
, NULL
, "suspend_lo", 0);
269 signal(SIGQUIT
, sig
[2]);
270 signal(SIGINT
, sig
[1]);
271 signal(SIGTERM
, sig
[0]);
272 if(munlockall() != 0) {
300 unsigned long long getnum(char *str
, char **err
)
303 unsigned long long rv
= strtoull(str
, &e
, 10);
311 int main(int argc
, char *argv
[])
313 /* md_device start length */
316 char **disk_name
= NULL
;
317 unsigned long long *offsets
= NULL
;
324 int failed_disk1
, failed_disk2
;
325 unsigned long long start
, length
;
328 struct mdinfo
*info
= NULL
, *comp
= NULL
;
332 char *prg
= strrchr(argv
[0], '/');
340 fprintf(stderr
, "Usage: %s md_device start_stripe length_stripes\n", prg
);
341 fprintf(stderr
, " or: %s md_device repair stripe failed_slot_1 failed_slot_2\n", prg
);
346 mdfd
= open(argv
[1], O_RDONLY
);
349 fprintf(stderr
, "%s: cannot open %s\n", prg
, argv
[1]);
354 info
= sysfs_read(mdfd
, -1,
366 fprintf(stderr
, "%s: Error reading sysfs information of %s\n", prg
, argv
[1]);
371 if(info
->array
.level
!= level
) {
372 fprintf(stderr
, "%s: %s not a RAID-6\n", prg
, argv
[1]);
377 if(info
->array
.failed_disks
> 0) {
378 fprintf(stderr
, "%s: %s degraded array\n", prg
, argv
[1]);
383 printf("layout: %d\n", info
->array
.layout
);
384 printf("disks: %d\n", info
->array
.raid_disks
);
385 printf("component size: %llu\n", info
->component_size
* 512);
386 printf("total stripes: %llu\n", (info
->component_size
* 512) / info
->array
.chunk_size
);
387 printf("chunk size: %d\n", info
->array
.chunk_size
);
391 for(i
= 0, active_disks
= 0; active_disks
< info
->array
.raid_disks
; i
++) {
392 printf("disk: %d - offset: %llu - size: %llu - name: %s - slot: %d\n",
393 i
, comp
->data_offset
* 512, comp
->component_size
* 512,
394 map_dev(comp
->disk
.major
, comp
->disk
.minor
, 0),
395 comp
->disk
.raid_disk
);
396 if(comp
->disk
.raid_disk
>= 0)
404 raid_disks
= info
->array
.raid_disks
;
405 chunk_size
= info
->array
.chunk_size
;
406 layout
= info
->array
.layout
;
407 if (strcmp(argv
[2], "repair")==0) {
409 fprintf(stderr
, "For repair mode, call %s md_device repair stripe failed_slot_1 failed_slot_2\n", prg
);
414 start
= getnum(argv
[3], &err
);
416 failed_disk1
= getnum(argv
[4], &err
);
417 failed_disk2
= getnum(argv
[5], &err
);
419 if(failed_disk1
> info
->array
.raid_disks
) {
420 fprintf(stderr
, "%s: failed_slot_1 index is higher than number of devices in raid\n", prg
);
424 if(failed_disk2
> info
->array
.raid_disks
) {
425 fprintf(stderr
, "%s: failed_slot_2 index is higher than number of devices in raid\n", prg
);
429 if(failed_disk1
== failed_disk2
) {
430 fprintf(stderr
, "%s: failed_slot_1 and failed_slot_2 are the same\n", prg
);
436 start
= getnum(argv
[2], &err
);
437 length
= getnum(argv
[3], &err
);
441 fprintf(stderr
, "%s: Bad number: %s\n", prg
, err
);
446 if(start
> ((info
->component_size
* 512) / chunk_size
)) {
447 start
= (info
->component_size
* 512) / chunk_size
;
448 fprintf(stderr
, "%s: start beyond disks size\n", prg
);
452 ((length
+ start
) > ((info
->component_size
* 512) / chunk_size
))) {
453 length
= (info
->component_size
* 512) / chunk_size
- start
;
456 disk_name
= xmalloc(raid_disks
* sizeof(*disk_name
));
457 fds
= xmalloc(raid_disks
* sizeof(*fds
));
458 offsets
= xcalloc(raid_disks
, sizeof(*offsets
));
459 buf
= xmalloc(raid_disks
* chunk_size
);
461 for(i
=0; i
<raid_disks
; i
++) {
467 for (i
=0, active_disks
=0; active_disks
<raid_disks
; i
++) {
468 int disk_slot
= comp
->disk
.raid_disk
;
470 disk_name
[disk_slot
] = map_dev(comp
->disk
.major
, comp
->disk
.minor
, 0);
471 offsets
[disk_slot
] = comp
->data_offset
* 512;
472 fds
[disk_slot
] = open(disk_name
[disk_slot
], O_RDWR
);
473 if (fds
[disk_slot
] < 0) {
474 perror(disk_name
[disk_slot
]);
475 fprintf(stderr
,"%s: cannot open %s\n", prg
, disk_name
[disk_slot
]);
484 int rv
= check_stripes(info
, fds
, offsets
,
485 raid_disks
, chunk_size
, level
, layout
,
486 start
, length
, disk_name
, repair
, failed_disk1
, failed_disk2
);
489 "%s: check_stripes returned %d\n", prg
, rv
);
497 for(i
= 0; i
< raid_disks
; i
++)