]>
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
28 int geo_map(int block
, unsigned long long stripe
, int raid_disks
,
29 int level
, int layout
);
30 void qsyndrome(uint8_t *p
, uint8_t *q
, uint8_t **sources
, int disks
, int size
);
31 void make_tables(void);
33 /* Collect per stripe consistency information */
34 void raid6_collect(int chunk_size
, uint8_t *p
, uint8_t *q
,
35 char *chunkP
, char *chunkQ
, int *results
)
40 extern uint8_t raid6_gflog
[];
42 for(i
= 0; i
< chunk_size
; i
++) {
43 Px
= (uint8_t)chunkP
[i
] ^ (uint8_t)p
[i
];
44 Qx
= (uint8_t)chunkQ
[i
] ^ (uint8_t)q
[i
];
46 if((Px
!= 0) && (Qx
== 0))
49 if((Px
== 0) && (Qx
!= 0))
52 if((Px
!= 0) && (Qx
!= 0)) {
53 data_id
= (raid6_gflog
[Qx
] - raid6_gflog
[Px
]);
54 if(data_id
< 0) data_id
+= 255;
58 if((Px
== 0) && (Qx
== 0))
63 /* Try to find out if a specific disk has problems */
64 int raid6_stats(int *results
, int raid_disks
, int chunk_size
)
67 int curr_broken_disk
= -255;
68 int prev_broken_disk
= -255;
69 int broken_status
= 0;
71 for(i
= 0; i
< chunk_size
; i
++) {
73 if(results
[i
] != -255)
74 curr_broken_disk
= results
[i
];
76 if(curr_broken_disk
>= raid_disks
)
79 switch(broken_status
) {
81 if(curr_broken_disk
!= -255) {
82 prev_broken_disk
= curr_broken_disk
;
88 if(curr_broken_disk
!= prev_broken_disk
)
94 curr_broken_disk
= prev_broken_disk
= -65535;
99 return curr_broken_disk
;
102 int check_stripes(int *source
, unsigned long long *offsets
,
103 int raid_disks
, int chunk_size
, int level
, int layout
,
104 unsigned long long start
, unsigned long long length
, char *name
[])
106 /* read the data and p and q blocks, and check we got them right */
107 char *stripe_buf
= malloc(raid_disks
* chunk_size
);
108 char **stripes
= malloc(raid_disks
* sizeof(char*));
109 char **blocks
= malloc(raid_disks
* sizeof(char*));
110 uint8_t *p
= malloc(chunk_size
);
111 uint8_t *q
= malloc(chunk_size
);
112 int *results
= malloc(chunk_size
* sizeof(int));
116 int data_disks
= raid_disks
- 2;
119 extern int tables_ready
;
121 if((stripe_buf
== NULL
) ||
134 for ( i
= 0 ; i
< raid_disks
; i
++)
135 stripes
[i
] = stripe_buf
+ i
* chunk_size
;
140 printf("pos --> %llu\n", start
);
142 for (i
= 0 ; i
< raid_disks
; i
++) {
143 lseek64(source
[i
], offsets
[i
] + start
* chunk_size
, 0);
144 read(source
[i
], stripes
[i
], chunk_size
);
146 for (i
= 0 ; i
< data_disks
; i
++) {
147 int disk
= geo_map(i
, start
, raid_disks
, level
, layout
);
148 blocks
[i
] = stripes
[disk
];
149 printf("%d->%d\n", i
, disk
);
152 qsyndrome(p
, q
, (uint8_t**)blocks
, data_disks
, chunk_size
);
153 diskP
= geo_map(-1, start
, raid_disks
, level
, layout
);
154 if (memcmp(p
, stripes
[diskP
], chunk_size
) != 0) {
155 printf("P(%d) wrong at %llu\n", diskP
, start
);
157 diskQ
= geo_map(-2, start
, raid_disks
, level
, layout
);
158 if (memcmp(q
, stripes
[diskQ
], chunk_size
) != 0) {
159 printf("Q(%d) wrong at %llu\n", diskQ
, start
);
161 raid6_collect(chunk_size
, p
, q
, stripes
[diskP
], stripes
[diskQ
], results
);
162 disk
= raid6_stats(results
, raid_disks
, chunk_size
);
165 disk
= geo_map(disk
, start
, raid_disks
, level
, layout
);
168 printf("Error detected at %llu: possible failed disk slot: %d --> %s\n",
169 start
, disk
, name
[disk
]);
172 printf("Error detected at %llu: disk slot unknown\n", start
);
191 unsigned long long getnum(char *str
, char **err
)
194 unsigned long long rv
= strtoull(str
, &e
, 10);
202 int main(int argc
, char *argv
[])
204 /* md_device start length */
207 char **disk_name
= NULL
;
208 unsigned long long *offsets
= NULL
;
214 unsigned long long start
, length
;
217 struct mdinfo
*info
, *comp
;
221 char *prg
= strrchr(argv
[0], '/');
229 fprintf(stderr
, "Usage: %s md_device start_stripe length_stripes\n", prg
);
234 mdfd
= open(argv
[1], O_RDONLY
);
237 fprintf(stderr
,"%s: cannot open %s\n", prg
, argv
[1]);
242 info
= sysfs_read(mdfd
, -1,
253 if(info
->array
.level
!= level
) {
254 fprintf(stderr
, "%s: %s not a RAID-6\n", prg
, argv
[1]);
259 if(info
->array
.failed_disks
> 0) {
260 fprintf(stderr
, "%s: %s degraded array\n", prg
, argv
[1]);
265 printf("layout: %d\n", info
->array
.layout
);
266 printf("disks: %d\n", info
->array
.raid_disks
);
267 printf("component size: %llu\n", info
->component_size
* 512);
268 printf("total stripes: %llu\n", (info
->component_size
* 512) / info
->array
.chunk_size
);
269 printf("chunk size: %d\n", info
->array
.chunk_size
);
273 for(i
= 0, active_disks
= 0; active_disks
< info
->array
.raid_disks
; i
++) {
274 printf("disk: %d - offset: %llu - size: %llu - name: %s - slot: %d\n",
275 i
, comp
->data_offset
* 512, comp
->component_size
* 512,
276 map_dev(comp
->disk
.major
, comp
->disk
.minor
, 0),
277 comp
->disk
.raid_disk
);
278 if(comp
->disk
.raid_disk
>= 0)
286 raid_disks
= info
->array
.raid_disks
;
287 chunk_size
= info
->array
.chunk_size
;
288 layout
= info
->array
.layout
;
289 start
= getnum(argv
[2], &err
);
290 length
= getnum(argv
[3], &err
);
293 fprintf(stderr
, "%s: Bad number: %s\n", prg
, err
);
298 if(start
> ((info
->component_size
* 512) / chunk_size
)) {
299 start
= (info
->component_size
* 512) / chunk_size
;
300 fprintf(stderr
, "%s: start beyond disks size\n", prg
);
304 ((length
+ start
) > ((info
->component_size
* 512) / chunk_size
))) {
305 length
= (info
->component_size
* 512) / chunk_size
- start
;
308 disk_name
= malloc(raid_disks
* sizeof(*disk_name
));
309 fds
= malloc(raid_disks
* sizeof(*fds
));
310 offsets
= malloc(raid_disks
* sizeof(*offsets
));
311 buf
= malloc(raid_disks
* chunk_size
);
313 if((disk_name
== NULL
) ||
317 fprintf(stderr
, "%s: allocation fail\n", prg
);
322 memset(offsets
, 0, raid_disks
* sizeof(*offsets
));
323 for(i
=0; i
<raid_disks
; i
++) {
329 for (i
=0, active_disks
=0; active_disks
<raid_disks
; i
++) {
330 int disk_slot
= comp
->disk
.raid_disk
;
332 disk_name
[disk_slot
] = map_dev(comp
->disk
.major
, comp
->disk
.minor
, 0);
333 offsets
[disk_slot
] = comp
->data_offset
* 512;
334 fds
[disk_slot
] = open(disk_name
[disk_slot
], O_RDWR
);
335 if (fds
[disk_slot
] < 0) {
336 perror(disk_name
[disk_slot
]);
337 fprintf(stderr
,"%s: cannot open %s\n", prg
, disk_name
[disk_slot
]);
346 int rv
= check_stripes(fds
, offsets
,
347 raid_disks
, chunk_size
, level
, layout
,
348 start
, length
, disk_name
);
351 "%s: check_stripes returned %d\n", prg
, rv
);
359 for(i
= 0; i
< raid_disks
; i
++)