/*
* mdadm - manage Linux "md" devices aka RAID arrays.
*
* Copyright (C) 2013 Neil Brown <neilb@suse.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* Author: Neil Brown
* Email: <neilb@suse.de>
*/
#include "mdadm.h"
#include <sys/dir.h>
int Dump_metadata(char *dev, char *dir, struct context *c,
struct supertype *st)
{
/* create a new file in 'dir' named for the basename of 'dev'.
* Truncate to the same size as 'dev' and ask the metadata
* handler to copy metadata there.
* For every name in /dev/disk/by-id that points to this device,
* create a hardlink in 'dir'.
* Complain if any of those hardlinks cannot be created.
*/
int fd, fl;
struct stat stb, dstb;
char *base;
char *fname = NULL;
unsigned long long size;
DIR *dirp;
struct dirent *de;
if (stat(dir, &stb) != 0 ||
(S_IFMT & stb.st_mode) != S_IFDIR) {
pr_err("--dump requires an existing directory, not: %s\n",
dir);
return 16;
}
fd = dev_open(dev, O_RDONLY);
if (fd < 0) {
pr_err("Cannot open %s to dump metadata: %s\n",
dev, strerror(errno));
return 1;
}
if (!get_dev_size(fd, dev, &size)) {
close(fd);
return 1;
}
if (st == NULL)
st = guess_super_type(fd, guess_array);
if (!st) {
pr_err("Cannot find RAID metadata on %s\n", dev);
close(fd);
return 1;
}
st->ignore_hw_compat = 1;
if (st->ss->load_super(st, fd, NULL) != 0) {
pr_err("No %s metadata found on %s\n",
st->ss->name, dev);
close(fd);
return 1;
}
if (st->ss->copy_metadata == NULL) {
pr_err("%s metadata on %s cannot be copied\n",
st->ss->name, dev);
close(fd);
return 1;
}
base = strrchr(dev, '/');
if (base)
base++;
else
base = dev;
xasprintf(&fname, "%s/%s", dir, base);
fl = open(fname, O_RDWR|O_CREAT|O_EXCL, 0666);
if (fl < 0) {
pr_err("Cannot create dump file %s: %s\n",
fname, strerror(errno));
close(fd);
free(fname);
return 1;
}
if (ftruncate(fl, size) < 0) {
pr_err("failed to set size of dump file: %s\n",
strerror(errno));
close(fd);
close(fl);
free(fname);
return 1;
}
if (st->ss->copy_metadata(st, fd, fl) != 0) {
pr_err("Failed to copy metadata from %s to %s\n",
dev, fname);
close(fd);
close(fl);
unlink(fname);
free(fname);
return 1;
}
if (c->verbose >= 0)
printf("%s saved as %s.\n", dev, fname);
fstat(fd, &dstb);
close(fd);
close(fl);
if ((dstb.st_mode & S_IFMT) != S_IFBLK) {
/* Not a block device, so cannot create links */
free(fname);
return 0;
}
/* mostly done: just want to find some other names */
dirp = opendir("/dev/disk/by-id");
if (!dirp) {
free(fname);
return 0;
}
while ((de = readdir(dirp)) != NULL) {
char *p = NULL;
if (de->d_name[0] == '.')
continue;
xasprintf(&p, "/dev/disk/by-id/%s", de->d_name);
if (stat(p, &stb) != 0 ||
(stb.st_mode & S_IFMT) != S_IFBLK ||
stb.st_rdev != dstb.st_rdev) {
/* Not this one */
free(p);
continue;
}
free(p);
xasprintf(&p, "%s/%s", dir, de->d_name);
if (link(fname, p) == 0) {
if (c->verbose >= 0)
printf("%s also saved as %s.\n",
dev, p);
} else {
pr_err("Could not save %s as %s!!\n",
dev, p);
}
free(p);
}
closedir(dirp);
free(fname);
return 0;
}
int Restore_metadata(char *dev, char *dir, struct context *c,
struct supertype *st, int only)
{
/* If 'dir' really is a directory we choose a name
* from it that matches a suitable name in /dev/disk/by-id,
* and copy metadata from the file to the device.
* If two names from by-id match and aren't both the same
* inode, we fail. If none match and basename of 'dev'
* can be found in dir, use that.
* If 'dir' is really a file then it is only permitted if
* 'only' is set (meaning there was only one device given)
* and the metadata is restored irrespective of file names.
*/
int fd, fl;
struct stat stb, dstb;
char *fname = NULL;
unsigned long long size;
if (stat(dir, &stb) != 0) {
pr_err("%s does not exist: cannot restore from there.\n",
dir);
return 16;
} else if ((S_IFMT & stb.st_mode) != S_IFDIR && !only) {
pr_err("--restore requires a directory when multiple devices given\n");
return 16;
}
fd = dev_open(dev, O_RDWR);
if (fd < 0) {
pr_err("Cannot open %s to restore metadata: %s\n",
dev, strerror(errno));
return 1;
}
if (!get_dev_size(fd, dev, &size)) {
close(fd);
return 1;
}
if ((S_IFMT & stb.st_mode) == S_IFDIR) {
/* choose one name from the directory. */
DIR *d = opendir(dir);
struct dirent *de;
char *chosen = NULL;
unsigned int chosen_inode = 0;
fstat(fd, &dstb);
while (d && (de = readdir(d)) != NULL) {
if (de->d_name[0] == '.')
continue;
xasprintf(&fname, "/dev/disk/by-id/%s", de->d_name);
if (stat(fname, &stb) != 0) {
free(fname);
continue;
}
free(fname);
if ((S_IFMT & stb.st_mode) != S_IFBLK)
continue;
if (stb.st_rdev != dstb.st_rdev)
continue;
/* This file is a good match for our device. */
xasprintf(&fname, "%s/%s", dir, de->d_name);
if (stat(fname, &stb) != 0) {
/* Weird! */
free(fname);
continue;
}
if (chosen == NULL) {
chosen = fname;
chosen_inode = stb.st_ino;
continue;
}
if (chosen_inode == stb.st_ino) {
/* same, no need to change */
free(fname);
continue;
}
/* Oh dear, two names both match. Must give up. */
pr_err("Both %s and %s seem suitable for %s. Please choose one.\n",
chosen, fname, dev);
free(fname);
free(chosen);
close(fd);
closedir(d);
return 1;
}
closedir(d);
if (!chosen) {
/* One last chance: try basename of device */
char *base = strrchr(dev, '/');
if (base)
base++;
else
base = dev;
xasprintf(&fname, "%s/%s", dir, base);
if (stat(fname, &stb) == 0)
chosen = fname;
else
free(fname);
}
fname = chosen;
} else
fname = strdup(dir);
if (!fname) {
pr_err("Cannot find suitable file in %s for %s\n",
dir, dev);
close(fd);
return 1;
}
fl = open(fname, O_RDONLY);
if (!fl) {
pr_err("Could not open %s for --restore.\n",
fname);
goto err;
}
if (stat(fname, &stb) != 0) {
pr_err("Could not stat %s for --restore.\n",
fname);
goto err;
}
if (((unsigned long long)stb.st_size) != size) {
pr_err("%s is not the same size as %s - cannot restore.\n",
fname, dev);
goto err;
}
if (st == NULL)
st = guess_super_type(fl, guess_array);
if (!st) {
pr_err("Cannot find metadata on %s\n", fname);
goto err;
}
st->ignore_hw_compat = 1;
if (st->ss->load_super(st, fl, NULL) != 0) {
pr_err("No %s metadata found on %s\n",
st->ss->name, fname);
goto err;
}
if (st->ss->copy_metadata == NULL) {
pr_err("%s metadata on %s cannot be copied\n",
st->ss->name, dev);
goto err;
}
if (st->ss->copy_metadata(st, fl, fd) != 0) {
pr_err("Failed to copy metadata from %s to %s\n",
fname, dev);
goto err;
}
if (c->verbose >= 0)
printf("%s restored from %s.\n", dev, fname);
close(fl);
close(fd);
free(fname);
return 0;
err:
close(fd);
close(fl);
free(fname);
return 1;
}