X-Git-Url: http://git.ipfire.org/?a=blobdiff_plain;f=mdopen.c;h=21baf5da8bb5532e2eff3f494598758f2624e7c6;hb=f58dd437412348b77bc09b79c656cf3472e9913d;hp=9250e4bacf3062b308157c83480de7561603ed1c;hpb=7b403fef7e97c16e1eb63773a278eb65c6dfd9a8;p=thirdparty%2Fmdadm.git diff --git a/mdopen.c b/mdopen.c index 9250e4ba..21baf5da 100644 --- a/mdopen.c +++ b/mdopen.c @@ -1,7 +1,7 @@ /* * mdadm - manage Linux "md" devices aka RAID arrays. * - * Copyright (C) 2001-2006 Neil Brown + * Copyright (C) 2001-2009 Neil Brown * * * This program is free software; you can redistribute it and/or modify @@ -19,12 +19,7 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Author: Neil Brown - * Email: - * Paper: Neil Brown - * School of Computer Science and Engineering - * The University of New South Wales - * Sydney, 2052 - * Australia + * Email: */ #include "mdadm.h" @@ -32,45 +27,44 @@ #include -void make_dev_symlink(char *dev) -{ - char *new = strdup(dev); - - if (!new) return; - /* /dev/md/0 -> /dev/md0 - * /dev/md/d0 -> /dev/md_d0 - */ - if (isdigit(new[8])) - strcpy(new+7, new+8); - else - new[7] = '_'; - if (symlink(dev+5, new)) - perror(new); -} - - -void make_parts(char *dev, int cnt, int symlinks) +void make_parts(char *dev, int cnt) { /* make 'cnt' partition devices for 'dev' - * We use the major/minor from dev and add 1..cnt + * If dev is a device name we use the + * major/minor from dev and add 1..cnt + * If it is a symlink, we make similar symlinks. * If dev ends with a digit, we add "p%d" else "%d" * If the name exists, we use it's owner/mode, * else that of dev */ struct stat stb; - int major_num, minor_num; + int major_num = major_num; /* quiet gcc -Os unitialized warning */ + int minor_num = minor_num; /* quiet gcc -Os unitialized warning */ + int odig = odig; /* quiet gcc -Os unitialized warning */ int i; int nlen = strlen(dev) + 20; - char *name = malloc(nlen); + char *name; int dig = isdigit(dev[strlen(dev)-1]); + char orig[1024]; + char sym[1024]; + int err; if (cnt==0) cnt=4; - if (stat(dev, &stb)!= 0) + if (lstat(dev, &stb)!= 0) return; - if (!S_ISBLK(stb.st_mode)) - return; - major_num = major(stb.st_rdev); - minor_num = minor(stb.st_rdev); + + if (S_ISLNK(stb.st_mode)) { + int len = readlink(dev, orig, sizeof(orig)); + if (len < 0 || len > 1000) + return; + orig[len] = 0; + odig = isdigit(orig[len-1]); + } else if (S_ISBLK(stb.st_mode)) { + major_num = major(stb.st_rdev); + minor_num = minor(stb.st_rdev); + } else + return; + name = malloc(nlen); for (i=1; i <= cnt ; i++) { struct stat stb2; snprintf(name, nlen, "%s%s%d", dev, dig?"p":"", i); @@ -83,39 +77,76 @@ void make_parts(char *dev, int cnt, int symlinks) } else { stb2 = stb; } - if (mknod(name, S_IFBLK | 0600, makedev(major_num, minor_num+i))) - perror("mknod"); - if (chown(name, stb2.st_uid, stb2.st_gid)) - perror("chown"); - if (chmod(name, stb2.st_mode & 07777)) - perror("chmod"); - if (symlinks && strncmp(name, "/dev/md/", 8) == 0) - make_dev_symlink(name); - stat(name, &stb2); - add_dev(name, &stb2, 0, NULL); + if (S_ISBLK(stb.st_mode)) { + if (mknod(name, S_IFBLK | 0600, + makedev(major_num, minor_num+i))) + perror("mknod"); + if (chown(name, stb2.st_uid, stb2.st_gid)) + perror("chown"); + if (chmod(name, stb2.st_mode & 07777)) + perror("chmod"); + err = 0; + } else { + snprintf(sym, sizeof(sym), "%s%s%d", orig, odig?"p":"", i); + err = symlink(sym, name); + } + + if (err == 0 && stat(name, &stb2) == 0) + add_dev(name, &stb2, 0, NULL); } + free(name); } /* - * Open a given md device, and check that it really is one. - * If 'autof' is given, then we need to create, or recreate, the md device. - * If the name already exists, and is not a block device, we fail. - * If it exists and is not an md device, is not the right type (partitioned or not), - * or is currently in-use, we remove the device, but remember the owner and mode. - * If it now doesn't exist, we find a new md array and create the device. - * Default ownership/mode comes from config file. + * We need a new md device to assemble/build/create an array. + * 'dev' is a name given us by the user (command line or mdadm.conf) + * It might start with /dev or /dev/md any might end with a digit + * string. + * If it starts with just /dev, it must be /dev/mdX or /dev/md_dX + * If it ends with a digit string, then it must be as above, or + * 'trustworthy' must be 'METADATA' and the 'dev' must be + * /dev/md/'name'NN or 'name'NN + * If it doesn't end with a digit string, it must be /dev/md/'name' + * or 'name' or must be NULL. + * If the digit string is present, it gives the minor number to use + * If not, we choose a high, unused minor number. + * If the 'dev' is a standard name, it devices whether 'md' or 'mdp'. + * else if the name is 'd[0-9]+' then we use mdp + * else if trustworthy is 'METADATA' we use md + * else the choice depends on 'autof'. + * If name is NULL it is assumed to match whatever dev provides. + * If both name and dev are NULL, we choose a name 'mdXX' or 'mdpXX' + * + * If 'name' is given, and 'trustworthy' is 'foreign' and name is not + * supported by 'dev', we add a "_%d" suffix based on the minor number + * use that. + * + * If udev is configured, we create a temporary device, open it, and + * unlink it. + * If not, we create the /dev/mdXX device, and is name is usable, + * /dev/md/name + * In any case we return /dev/md/name or (if that isn't available) + * /dev/mdXX in 'chosen'. + * + * When we create devices, we use uid/gid/umask from config file. */ -int open_mddev(char *dev, int autof) + +int create_mddev(char *dev, char *name, int autof, int trustworthy, + char *chosen) { int mdfd; struct stat stb; - int major_num = MD_MAJOR; - int minor_num = 0; - int must_remove = 0; - int num; + int num = -1; + int use_mdp = -1; struct createinfo *ci = conf_get_create_info(); int parts; + char *cname; + char devname[20]; + char cbuf[400]; + if (chosen == NULL) + chosen = cbuf; + if (autof == 0) autof = ci->autof; @@ -123,226 +154,254 @@ int open_mddev(char *dev, int autof) parts = autof >> 3; autof &= 7; - if (autof && autof != 1) { - /* autof is set, so we need to check that the name is ok, - * and possibly create one if not - */ - int std; - stb.st_mode = 0; - if (stat(dev, &stb)==0 && ! S_ISBLK(stb.st_mode)) { - fprintf(stderr, Name ": %s is not a block device.\n", - dev); - return -1; - } - /* check major number is correct */ - num = -1; - std = is_standard(dev, &num); - if (std>0) major_num = get_mdp_major(); - switch(autof) { - case 2: /* only create is_standard names */ - if (!std && !stb.st_mode) { - fprintf(stderr, Name - ": %s does not exist and is not a 'standard' name " - "so it cannot be created\n", dev); - return -1; - } - break; - case 3: /* create md, reject std>0 */ - if (std > 0) { - fprintf(stderr, Name ": that --auto option " - "not compatable with device named %s\n", dev); - return -1; - } - break; - case 4: /* create mdp, reject std<0 */ - if (std < 0) { - fprintf(stderr, Name ": that --auto option " - "not compatable with device named %s\n", dev); + strcpy(chosen, "/dev/md/"); + cname = chosen + strlen(chosen); + + + if (dev) { + if (strncmp(dev, "/dev/md/", 8) == 0) { + strcpy(cname, dev+8); + } else if (strncmp(dev, "/dev/", 5) == 0) { + char *e = dev + strlen(dev); + while (e > dev && isdigit(e[-1])) + e--; + if (e[0]) + num = strtoul(e, NULL, 10); + strcpy(cname, dev+5); + cname[e-(dev+5)] = 0; + /* name *must* be mdXX or md_dXX in this context */ + if (num < 0 || + (strcmp(cname, "md") != 0 && strcmp(cname, "md_d") != 0)) { + fprintf(stderr, Name ": %s is an invalid name " + "for an md device. Try /dev/md/%s\n", + dev, dev+5); return -1; } - major_num = get_mdp_major(); - break; - case 5: /* default to md if not standard */ - break; - case 6: /* default to mdp if not standard */ - if (std == 0) major_num = get_mdp_major(); - break; + if (strcmp(cname, "md") == 0) + use_mdp = 0; + else + use_mdp = 1; + /* recreate name: /dev/md/0 or /dev/md/d0 */ + sprintf(cname, "%s%d", use_mdp?"d":"", num); + } else + strcpy(cname, dev); + + /* 'cname' must not contain a slash, and may not be + * empty. + */ + if (strchr(cname, '/') != NULL) { + fprintf(stderr, Name ": %s is an invalid name " + "for an md device.\n", dev); + return -1; } - /* major is final. num is -1 if not standard */ - if (stb.st_mode && major(stb.st_rdev) != major_num) - must_remove = 1; - if (stb.st_mode && !must_remove) { - /* looks ok, see if it is available */ - mdfd = open(dev, O_RDWR); - if (mdfd < 0) { - fprintf(stderr, Name ": error opening %s: %s\n", - dev, strerror(errno)); - return -1; - } else if (md_get_version(mdfd) <= 0) { - fprintf(stderr, Name ": %s does not appear to be an md device\n", - dev); - close(mdfd); - return -1; - } - if (major_num != MD_MAJOR && parts > 0) - make_parts(dev, parts, ci->symlinks); - return mdfd; + if (cname[0] == 0) { + fprintf(stderr, Name ": %s is an invalid name " + "for an md device (empty!).", dev); + return -1; } - /* Ok, need to find a minor that is not in use. - * If the device name is in a 'standard' format, - * intuit the minor from that, else - * easiest to read /proc/mdstat, and hunt through for - * an unused number - */ if (num < 0) { - /* need to pick an unused number */ - int num = find_free_devnum(major_num != MD_MAJOR); - - if (major_num == MD_MAJOR) - minor_num = num; + /* If cname is 'N' or 'dN', we get dev number + * from there. + */ + char *sp = cname; + char *ep; + if (cname[0] == 'd') + sp++; + num = strtoul(sp, &ep, 10); + if (ep == sp || *ep || num < 0) + num = -1; + else if (cname[0] == 'd') + use_mdp = 1; else - minor_num = (-1-num) << MdpMinorShift; - } else if (major_num == MD_MAJOR) - minor_num = num; - else - minor_num = num << MdpMinorShift; - /* major and minor have been chosen */ - - /* If it was a 'standard' name and it is in-use, then - * the device could already be correct - */ - if (stb.st_mode && major(stb.st_rdev) == major_num && - minor(stb.st_rdev) == minor_num) - ; - else { - if (major(makedev(major_num,minor_num)) != major_num || - minor(makedev(major_num,minor_num)) != minor_num) { - fprintf(stderr, Name ": Need newer C library to use more than 4 partitionable md devices, sorry\n"); - return -1; - } - if (must_remove) - unlink(dev); - - if (strncmp(dev, "/dev/md/", 8) == 0) { - if (mkdir("/dev/md",0700)==0) { - if (chown("/dev/md", ci->uid, ci->gid)) - perror("chown /dev/md"); - if (chmod("/dev/md", ci->mode| ((ci->mode>>2) & 0111))) - perror("chmod /dev/md"); - } - } - if (mknod(dev, S_IFBLK|0600, makedev(major_num, minor_num))!= 0) { - fprintf(stderr, Name ": failed to create %s\n", dev); - return -1; - } - if (must_remove) { - if (chown(dev, stb.st_uid, stb.st_gid)) - perror("chown"); - if (chmod(dev, stb.st_mode & 07777)) - perror("chmod"); - } else { - if (chown(dev, ci->uid, ci->gid)) - perror("chown"); - if (chmod(dev, ci->mode)) - perror("chmod"); - } - stat(dev, &stb); - add_dev(dev, &stb, 0, NULL); - if (ci->symlinks && strncmp(dev, "/dev/md/", 8) == 0) - make_dev_symlink(dev); - if (major_num != MD_MAJOR) - make_parts(dev,parts, ci->symlinks); + use_mdp = 0; } } - mdfd = open(dev, O_RDWR); - if (mdfd < 0) - fprintf(stderr, Name ": error opening %s: %s\n", - dev, strerror(errno)); - else if (md_get_version(mdfd) <= 0) { - fprintf(stderr, Name ": %s does not appear to be an md device\n", - dev); - close(mdfd); - mdfd = -1; - } - return mdfd; -} - -int open_mddev_devnum(char *devname, int devnum, char *name, - char *chosen_name, int parts) -{ - /* Open the md device with number 'devnum', possibly using 'devname', - * possibly constructing a name with 'name', but in any case, copying - * the name into 'chosen_name' - */ - int major_num, minor_num; - struct stat stb; - int i; - struct createinfo *ci = conf_get_create_info(); - - if (devname) - strcpy(chosen_name, devname); - else if (name && *name && strchr(name,'/') == NULL) { - char *n = strchr(name, ':'); - if (n) n++; else n = name; - if (isdigit(*n) && devnum < 0) - sprintf(chosen_name, "/dev/md/d%s", n); - else - sprintf(chosen_name, "/dev/md/%s", n); - } else { - if (devnum >= 0) - sprintf(chosen_name, "/dev/md%d", devnum); + /* Now determine device number */ + /* named 'METADATA' cannot use 'mdp'. */ + if (name && name[0] == 0) + name = NULL; + if (name && trustworthy == METADATA && use_mdp == 1) { + fprintf(stderr, Name ": %s is not allowed for a %s container. " + "Consider /dev/md%d.\n", dev, name, num); + return -1; + } + if (name && trustworthy == METADATA) + use_mdp = 0; + if (use_mdp == -1) { + if (autof == 4 || autof == 6) + use_mdp = 1; else - sprintf(chosen_name, "/dev/md/d%d", -1-devnum); + use_mdp = 0; } - if (devnum >= 0) { - major_num = MD_MAJOR; - minor_num = devnum; - } else { - major_num = get_mdp_major(); - minor_num = (-1-devnum) << 6; + if (num < 0 && trustworthy == LOCAL && name) { + /* if name is numeric, possibly prefixed by + * 'md' or '/dev/md', use that for num + * if it is not already in use */ + char *ep; + char *n2 = name; + if (strncmp(n2, "/dev/", 5) == 0) + n2 += 5; + if (strncmp(n2, "md", 2) == 0) + n2 += 2; + if (*n2 == '/') + n2++; + num = strtoul(n2, &ep, 10); + if (ep == n2 || *ep) + num = -1; + else if (mddev_busy(use_mdp ? (-1-num) : num)) + num = -1; } - if (stat(chosen_name, &stb) == 0) { - /* It already exists. Check it is right. */ - if ( ! S_ISBLK(stb.st_mode) || - stb.st_rdev != makedev(major_num, minor_num)) { - errno = EEXIST; + + if (num < 0) { + /* need to choose a free number. */ + num = find_free_devnum(use_mdp); + if (num == NoMdDev) { + fprintf(stderr, Name ": No avail md devices - aborting\n"); return -1; } } else { - /* special case: if --incremental is suggesting a name - * in /dev/md/, we make sure the directory exists. + num = use_mdp ? (-1-num) : num; + if (mddev_busy(num)) { + fprintf(stderr, Name ": %s is already in use.\n", + dev); + return -1; + } + } + + if (num < 0) + sprintf(devname, "/dev/md_d%d", -1-num); + else + sprintf(devname, "/dev/md%d", num); + + if (cname[0] == 0 && name) { + /* Need to find a name if we can + * We don't completely trust 'name'. Truncate to + * reasonable length and remove '/' */ - if (strncmp(chosen_name, "/dev/md/", 8) == 0) { + char *cp; + struct map_ent *map = NULL; + int conflict = 1; + int unum = 0; + int cnlen; + strncpy(cname, name, 200); + cname[200] = 0; + while ((cp = strchr(cname, '/')) != NULL) + *cp = '-'; + if (trustworthy == LOCAL || + (trustworthy == FOREIGN && strchr(cname, ':') != NULL)) { + /* Only need suffix if there is a conflict */ + if (map_by_name(&map, cname) == NULL) + conflict = 0; + } + cnlen = strlen(cname); + while (conflict) { + if (trustworthy == METADATA && !isdigit(cname[cnlen-1])) + sprintf(cname+cnlen, "%d", unum); + else + /* add _%d to FOREIGN array that don't + * a 'host:' prefix + */ + sprintf(cname+cnlen, "_%d", unum); + unum++; + if (map_by_name(&map, cname) == NULL) + conflict = 0; + } + } + + if (dev && dev[0] == '/') + strcpy(chosen, dev); + else if (cname[0] == 0) + strcpy(chosen, devname); + + /* We have a device number and name. + * If we cannot detect udev, we need to make + * devices and links ourselves. + */ + if (stat("/dev/.udev", &stb) != 0 || + check_env("MDADM_NO_UDEV")) { + /* Make sure 'devname' exists and 'chosen' is a symlink to it */ + if (lstat(devname, &stb) == 0) { + /* Must be the correct device, else error */ + if ((stb.st_mode&S_IFMT) != S_IFBLK || + stb.st_rdev != makedev(dev2major(num),dev2minor(num))) { + fprintf(stderr, Name ": %s exists but looks wrong, please fix\n", + devname); + return -1; + } + } else { + if (mknod(devname, S_IFBLK|0600, + makedev(dev2major(num),dev2minor(num))) != 0) { + fprintf(stderr, Name ": failed to create %s\n", + devname); + return -1; + } + if (chown(devname, ci->uid, ci->gid)) + perror("chown"); + if (chmod(devname, ci->mode)) + perror("chmod"); + stat(devname, &stb); + add_dev(devname, &stb, 0, NULL); + } + if (use_mdp == 1) + make_parts(devname, parts); + if (strcmp(chosen, devname) != 0) { + if (mkdir("/dev/md",0700)==0) { if (chown("/dev/md", ci->uid, ci->gid)) perror("chown /dev/md"); - if (chmod("/dev/md", ci->mode| - ((ci->mode>>2) & 0111))) + if (chmod("/dev/md", ci->mode| ((ci->mode>>2) & 0111))) perror("chmod /dev/md"); } - } - if (mknod(chosen_name, S_IFBLK | 0600, - makedev(major_num, minor_num)) != 0) { - return -1; + if (dev && strcmp(chosen, dev) == 0) + /* We know we are allowed to use this name */ + unlink(chosen); + + if (lstat(chosen, &stb) == 0) { + char buf[300]; + if ((stb.st_mode & S_IFMT) != S_IFLNK || + readlink(chosen, buf, 300) <0 || + strcmp(buf, devname) != 0) { + fprintf(stderr, Name ": %s exists - ignoring\n", + chosen); + strcpy(chosen, devname); + } + } else if (symlink(devname, chosen) != 0) + fprintf(stderr, Name ": failed to create %s: %s\n", + chosen, strerror(errno)); + if (use_mdp && strcmp(chosen, devname) != 0) + make_parts(chosen, parts); } - /* FIXME chown/chmod ?? */ } + mdfd = open_dev_excl(num); + if (mdfd < 0) + fprintf(stderr, Name ": unexpected failure opening %s\n", + devname); + return mdfd; +} - /* Simple locking to avoid --incr being called for the same - * array multiple times in parallel. - */ - for (i = 0; i < 25 ; i++) { - int fd; - fd = open(chosen_name, O_RDWR|O_EXCL); - if (fd >= 0 || errno != EBUSY) { - if (devnum < 0) - make_parts(chosen_name, parts, ci->symlinks); - return fd; - } - usleep(200000); +/* Open this and check that it is an md device. + * On success, return filedescriptor. + * On failure, return -1 if it doesn't exist, + * or -2 if it exists but is not an md device. + */ +int open_mddev(char *dev, int report_errors) +{ + int mdfd = open(dev, O_RDWR); + if (mdfd < 0) { + if (report_errors) + fprintf(stderr, Name ": error opening %s: %s\n", + dev, strerror(errno)); + return -1; } - return -1; + if (md_get_version(mdfd) <= 0) { + close(mdfd); + if (report_errors) + fprintf(stderr, Name ": %s does not appear to be " + "an md device\n", dev); + return -2; + } + return mdfd; }