1457c8996SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 21da177e4SLinus Torvalds #include <linux/module.h> 31da177e4SLinus Torvalds #include <linux/sched.h> 41da177e4SLinus Torvalds #include <linux/ctype.h> 51da177e4SLinus Torvalds #include <linux/fd.h> 61da177e4SLinus Torvalds #include <linux/tty.h> 71da177e4SLinus Torvalds #include <linux/suspend.h> 81da177e4SLinus Torvalds #include <linux/root_dev.h> 91da177e4SLinus Torvalds #include <linux/security.h> 101da177e4SLinus Torvalds #include <linux/delay.h> 11dd2a345fSDave Gilbert #include <linux/genhd.h> 12d53d9f16SAndrew Morton #include <linux/mount.h> 13d779249eSGreg Kroah-Hartman #include <linux/device.h> 1446595390SAdrian Bunk #include <linux/init.h> 15011e3fcdSAdrian Bunk #include <linux/fs.h> 1682c8253aSAdrian Bunk #include <linux/initrd.h> 1722a9d645SArjan van de Ven #include <linux/async.h> 185ad4e53bSAl Viro #include <linux/fs_struct.h> 195a0e3ad6STejun Heo #include <linux/slab.h> 2057f150a5SRob Landley #include <linux/ramfs.h> 2116203a7aSRob Landley #include <linux/shmem_fs.h> 221da177e4SLinus Torvalds 231da177e4SLinus Torvalds #include <linux/nfs_fs.h> 241da177e4SLinus Torvalds #include <linux/nfs_fs_sb.h> 251da177e4SLinus Torvalds #include <linux/nfs_mount.h> 264f5b246bSChristoph Hellwig #include <linux/raid/detect.h> 27e262e32dSDavid Howells #include <uapi/linux/mount.h> 281da177e4SLinus Torvalds 291da177e4SLinus Torvalds #include "do_mounts.h" 301da177e4SLinus Torvalds 319b04c997STheodore Ts'o int root_mountflags = MS_RDONLY | MS_SILENT; 32f56f6d30SAdrian Bunk static char * __initdata root_device_name; 331da177e4SLinus Torvalds static char __initdata saved_root_name[64]; 3479975f13SWill Drewry static int root_wait; 351da177e4SLinus Torvalds 361da177e4SLinus Torvalds dev_t ROOT_DEV; 371da177e4SLinus Torvalds 381da177e4SLinus Torvalds static int __init load_ramdisk(char *str) 391da177e4SLinus Torvalds { 40c8376994SChristoph Hellwig pr_warn("ignoring the deprecated load_ramdisk= option\n"); 411da177e4SLinus Torvalds return 1; 421da177e4SLinus Torvalds } 431da177e4SLinus Torvalds __setup("load_ramdisk=", load_ramdisk); 441da177e4SLinus Torvalds 451da177e4SLinus Torvalds static int __init readonly(char *str) 461da177e4SLinus Torvalds { 471da177e4SLinus Torvalds if (*str) 481da177e4SLinus Torvalds return 0; 491da177e4SLinus Torvalds root_mountflags |= MS_RDONLY; 501da177e4SLinus Torvalds return 1; 511da177e4SLinus Torvalds } 521da177e4SLinus Torvalds 531da177e4SLinus Torvalds static int __init readwrite(char *str) 541da177e4SLinus Torvalds { 551da177e4SLinus Torvalds if (*str) 561da177e4SLinus Torvalds return 0; 571da177e4SLinus Torvalds root_mountflags &= ~MS_RDONLY; 581da177e4SLinus Torvalds return 1; 591da177e4SLinus Torvalds } 601da177e4SLinus Torvalds 611da177e4SLinus Torvalds __setup("ro", readonly); 621da177e4SLinus Torvalds __setup("rw", readwrite); 631da177e4SLinus Torvalds 646d0aed7aSJens Axboe #ifdef CONFIG_BLOCK 651ad7e899SStephen Warren struct uuidcmp { 661ad7e899SStephen Warren const char *uuid; 671ad7e899SStephen Warren int len; 681ad7e899SStephen Warren }; 691ad7e899SStephen Warren 70b5af921eSWill Drewry /** 71b5af921eSWill Drewry * match_dev_by_uuid - callback for finding a partition using its uuid 72b5af921eSWill Drewry * @dev: device passed in by the caller 731ad7e899SStephen Warren * @data: opaque pointer to the desired struct uuidcmp to match 74b5af921eSWill Drewry * 75b5af921eSWill Drewry * Returns 1 if the device matches, and 0 otherwise. 76b5af921eSWill Drewry */ 779f3b795aSMichał Mirosław static int match_dev_by_uuid(struct device *dev, const void *data) 78b5af921eSWill Drewry { 799f3b795aSMichał Mirosław const struct uuidcmp *cmp = data; 80b5af921eSWill Drewry struct hd_struct *part = dev_to_part(dev); 81b5af921eSWill Drewry 82b5af921eSWill Drewry if (!part->info) 83b5af921eSWill Drewry goto no_match; 84b5af921eSWill Drewry 851ad7e899SStephen Warren if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len)) 86b5af921eSWill Drewry goto no_match; 87b5af921eSWill Drewry 88b5af921eSWill Drewry return 1; 89b5af921eSWill Drewry no_match: 90b5af921eSWill Drewry return 0; 91b5af921eSWill Drewry } 92b5af921eSWill Drewry 93b5af921eSWill Drewry /** 94b5af921eSWill Drewry * devt_from_partuuid - looks up the dev_t of a partition by its UUID 95a68b3108Schishanmingshen * @uuid_str: char array containing ascii UUID 96b5af921eSWill Drewry * 97b5af921eSWill Drewry * The function will return the first partition which contains a matching 98b5af921eSWill Drewry * UUID value in its partition_meta_info struct. This does not search 99b5af921eSWill Drewry * by filesystem UUIDs. 100b5af921eSWill Drewry * 101a68b3108Schishanmingshen * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be 10279975f13SWill Drewry * extracted and used as an offset from the partition identified by the UUID. 10379975f13SWill Drewry * 104b5af921eSWill Drewry * Returns the matching dev_t on success or 0 on failure. 105b5af921eSWill Drewry */ 1061ad7e899SStephen Warren static dev_t devt_from_partuuid(const char *uuid_str) 107b5af921eSWill Drewry { 108b5af921eSWill Drewry dev_t res = 0; 1091ad7e899SStephen Warren struct uuidcmp cmp; 110b5af921eSWill Drewry struct device *dev = NULL; 11179975f13SWill Drewry struct gendisk *disk; 11279975f13SWill Drewry struct hd_struct *part; 11379975f13SWill Drewry int offset = 0; 114283f8fc0SStephen Warren bool clear_root_wait = false; 115283f8fc0SStephen Warren char *slash; 11679975f13SWill Drewry 1171ad7e899SStephen Warren cmp.uuid = uuid_str; 1181ad7e899SStephen Warren 119283f8fc0SStephen Warren slash = strchr(uuid_str, '/'); 12079975f13SWill Drewry /* Check for optional partition number offset attributes. */ 121283f8fc0SStephen Warren if (slash) { 12279975f13SWill Drewry char c = 0; 12379975f13SWill Drewry /* Explicitly fail on poor PARTUUID syntax. */ 124283f8fc0SStephen Warren if (sscanf(slash + 1, 125283f8fc0SStephen Warren "PARTNROFF=%d%c", &offset, &c) != 1) { 126283f8fc0SStephen Warren clear_root_wait = true; 12779975f13SWill Drewry goto done; 12879975f13SWill Drewry } 129283f8fc0SStephen Warren cmp.len = slash - uuid_str; 130283f8fc0SStephen Warren } else { 131283f8fc0SStephen Warren cmp.len = strlen(uuid_str); 132283f8fc0SStephen Warren } 133283f8fc0SStephen Warren 134283f8fc0SStephen Warren if (!cmp.len) { 135283f8fc0SStephen Warren clear_root_wait = true; 136283f8fc0SStephen Warren goto done; 13779975f13SWill Drewry } 138b5af921eSWill Drewry 1391ad7e899SStephen Warren dev = class_find_device(&block_class, NULL, &cmp, 1401ad7e899SStephen Warren &match_dev_by_uuid); 141b5af921eSWill Drewry if (!dev) 142b5af921eSWill Drewry goto done; 143b5af921eSWill Drewry 144b5af921eSWill Drewry res = dev->devt; 145b5af921eSWill Drewry 14679975f13SWill Drewry /* Attempt to find the partition by offset. */ 14779975f13SWill Drewry if (!offset) 14879975f13SWill Drewry goto no_offset; 14979975f13SWill Drewry 15079975f13SWill Drewry res = 0; 15179975f13SWill Drewry disk = part_to_disk(dev_to_part(dev)); 15279975f13SWill Drewry part = disk_get_part(disk, dev_to_part(dev)->partno + offset); 15379975f13SWill Drewry if (part) { 15479975f13SWill Drewry res = part_devt(part); 15579975f13SWill Drewry put_device(part_to_dev(part)); 15679975f13SWill Drewry } 15779975f13SWill Drewry 15879975f13SWill Drewry no_offset: 15979975f13SWill Drewry put_device(dev); 160b5af921eSWill Drewry done: 161283f8fc0SStephen Warren if (clear_root_wait) { 162283f8fc0SStephen Warren pr_err("VFS: PARTUUID= is invalid.\n" 163283f8fc0SStephen Warren "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n"); 164283f8fc0SStephen Warren if (root_wait) 165283f8fc0SStephen Warren pr_err("Disabling rootwait; root= is invalid.\n"); 166283f8fc0SStephen Warren root_wait = 0; 167283f8fc0SStephen Warren } 168b5af921eSWill Drewry return res; 169b5af921eSWill Drewry } 170f027c34dSNikolaus Voss 171f027c34dSNikolaus Voss /** 172f027c34dSNikolaus Voss * match_dev_by_label - callback for finding a partition using its label 173f027c34dSNikolaus Voss * @dev: device passed in by the caller 174f027c34dSNikolaus Voss * @data: opaque pointer to the label to match 175f027c34dSNikolaus Voss * 176f027c34dSNikolaus Voss * Returns 1 if the device matches, and 0 otherwise. 177f027c34dSNikolaus Voss */ 178f027c34dSNikolaus Voss static int match_dev_by_label(struct device *dev, const void *data) 179f027c34dSNikolaus Voss { 180f027c34dSNikolaus Voss const char *label = data; 181f027c34dSNikolaus Voss struct hd_struct *part = dev_to_part(dev); 182f027c34dSNikolaus Voss 183f027c34dSNikolaus Voss if (part->info && !strcmp(label, part->info->volname)) 184f027c34dSNikolaus Voss return 1; 185f027c34dSNikolaus Voss 186f027c34dSNikolaus Voss return 0; 187f027c34dSNikolaus Voss } 188*c2637e80SChristoph Hellwig 189*c2637e80SChristoph Hellwig static dev_t devt_from_partlabel(const char *label) 190*c2637e80SChristoph Hellwig { 191*c2637e80SChristoph Hellwig struct device *dev; 192*c2637e80SChristoph Hellwig dev_t devt = 0; 193*c2637e80SChristoph Hellwig 194*c2637e80SChristoph Hellwig dev = class_find_device(&block_class, NULL, label, &match_dev_by_label); 195*c2637e80SChristoph Hellwig if (dev) { 196*c2637e80SChristoph Hellwig devt = dev->devt; 197*c2637e80SChristoph Hellwig put_device(dev); 198*c2637e80SChristoph Hellwig } 199*c2637e80SChristoph Hellwig 200*c2637e80SChristoph Hellwig return devt; 201*c2637e80SChristoph Hellwig } 202*c2637e80SChristoph Hellwig 203*c2637e80SChristoph Hellwig static dev_t devt_from_devname(const char *name) 204*c2637e80SChristoph Hellwig { 205*c2637e80SChristoph Hellwig dev_t devt = 0; 206*c2637e80SChristoph Hellwig int part; 207*c2637e80SChristoph Hellwig char s[32]; 208*c2637e80SChristoph Hellwig char *p; 209*c2637e80SChristoph Hellwig 210*c2637e80SChristoph Hellwig if (strlen(name) > 31) 211*c2637e80SChristoph Hellwig return 0; 212*c2637e80SChristoph Hellwig strcpy(s, name); 213*c2637e80SChristoph Hellwig for (p = s; *p; p++) { 214*c2637e80SChristoph Hellwig if (*p == '/') 215*c2637e80SChristoph Hellwig *p = '!'; 216*c2637e80SChristoph Hellwig } 217*c2637e80SChristoph Hellwig 218*c2637e80SChristoph Hellwig devt = blk_lookup_devt(s, 0); 219*c2637e80SChristoph Hellwig if (devt) 220*c2637e80SChristoph Hellwig return devt; 221*c2637e80SChristoph Hellwig 222*c2637e80SChristoph Hellwig /* 223*c2637e80SChristoph Hellwig * Try non-existent, but valid partition, which may only exist after 224*c2637e80SChristoph Hellwig * opening the device, like partitioned md devices. 225*c2637e80SChristoph Hellwig */ 226*c2637e80SChristoph Hellwig while (p > s && isdigit(p[-1])) 227*c2637e80SChristoph Hellwig p--; 228*c2637e80SChristoph Hellwig if (p == s || !*p || *p == '0') 229*c2637e80SChristoph Hellwig return 0; 230*c2637e80SChristoph Hellwig 231*c2637e80SChristoph Hellwig /* try disk name without <part number> */ 232*c2637e80SChristoph Hellwig part = simple_strtoul(p, NULL, 10); 233*c2637e80SChristoph Hellwig *p = '\0'; 234*c2637e80SChristoph Hellwig devt = blk_lookup_devt(s, part); 235*c2637e80SChristoph Hellwig if (devt) 236*c2637e80SChristoph Hellwig return devt; 237*c2637e80SChristoph Hellwig 238*c2637e80SChristoph Hellwig /* try disk name without p<part number> */ 239*c2637e80SChristoph Hellwig if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') 240*c2637e80SChristoph Hellwig return 0; 241*c2637e80SChristoph Hellwig p[-1] = '\0'; 242*c2637e80SChristoph Hellwig return blk_lookup_devt(s, part); 243*c2637e80SChristoph Hellwig } 244*c2637e80SChristoph Hellwig #endif /* CONFIG_BLOCK */ 245*c2637e80SChristoph Hellwig 246*c2637e80SChristoph Hellwig static dev_t devt_from_devnum(const char *name) 247*c2637e80SChristoph Hellwig { 248*c2637e80SChristoph Hellwig unsigned maj, min, offset; 249*c2637e80SChristoph Hellwig dev_t devt = 0; 250*c2637e80SChristoph Hellwig char *p, dummy; 251*c2637e80SChristoph Hellwig 252*c2637e80SChristoph Hellwig if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 || 253*c2637e80SChristoph Hellwig sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) { 254*c2637e80SChristoph Hellwig devt = MKDEV(maj, min); 255*c2637e80SChristoph Hellwig if (maj != MAJOR(devt) || min != MINOR(devt)) 256*c2637e80SChristoph Hellwig return 0; 257*c2637e80SChristoph Hellwig } else { 258*c2637e80SChristoph Hellwig devt = new_decode_dev(simple_strtoul(name, &p, 16)); 259*c2637e80SChristoph Hellwig if (*p) 260*c2637e80SChristoph Hellwig return 0; 261*c2637e80SChristoph Hellwig } 262*c2637e80SChristoph Hellwig 263*c2637e80SChristoph Hellwig return devt; 264*c2637e80SChristoph Hellwig } 265b5af921eSWill Drewry 2661da177e4SLinus Torvalds /* 2671da177e4SLinus Torvalds * Convert a name into device number. We accept the following variants: 2681da177e4SLinus Torvalds * 2690bf37ae4SPavel Machek * 1) <hex_major><hex_minor> device number in hexadecimal represents itself 2700bf37ae4SPavel Machek * no leading 0x, for example b302. 2711da177e4SLinus Torvalds * 2) /dev/nfs represents Root_NFS (0xff) 2721da177e4SLinus Torvalds * 3) /dev/<disk_name> represents the device number of disk 2731da177e4SLinus Torvalds * 4) /dev/<disk_name><decimal> represents the device number 2741da177e4SLinus Torvalds * of partition - device number of disk plus the partition number 2751da177e4SLinus Torvalds * 5) /dev/<disk_name>p<decimal> - same as the above, that form is 2761da177e4SLinus Torvalds * used when disk name of partitioned disk ends on a digit. 277b5af921eSWill Drewry * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the 278b5af921eSWill Drewry * unique id of a partition if the partition table provides it. 279d33b98fcSStephen Warren * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS 280d33b98fcSStephen Warren * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero- 281d33b98fcSStephen Warren * filled hex representation of the 32-bit "NT disk signature", and PP 282d33b98fcSStephen Warren * is a zero-filled hex representation of the 1-based partition number. 28379975f13SWill Drewry * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to 28479975f13SWill Drewry * a partition with a known unique id. 2856c251611SSebastian Capella * 8) <major>:<minor> major and minor number of the device separated by 2866c251611SSebastian Capella * a colon. 287f027c34dSNikolaus Voss * 9) PARTLABEL=<name> with name being the GPT partition label. 288f027c34dSNikolaus Voss * MSDOS partitions do not support labels! 2898902dd52SPaulo Alcantara (SUSE) * 10) /dev/cifs represents Root_CIFS (0xfe) 2901da177e4SLinus Torvalds * 291edfaa7c3SKay Sievers * If name doesn't have fall into the categories above, we return (0,0). 292edfaa7c3SKay Sievers * block_class is used to check if something is a disk name. If the disk 293edfaa7c3SKay Sievers * name contains slashes, the device name has them replaced with 294edfaa7c3SKay Sievers * bangs. 2951da177e4SLinus Torvalds */ 296e6e20a7aSDan Ehrenberg dev_t name_to_dev_t(const char *name) 2971da177e4SLinus Torvalds { 298*c2637e80SChristoph Hellwig if (strcmp(name, "/dev/nfs") == 0) 299*c2637e80SChristoph Hellwig return Root_NFS; 300*c2637e80SChristoph Hellwig if (strcmp(name, "/dev/cifs") == 0) 301*c2637e80SChristoph Hellwig return Root_CIFS; 302*c2637e80SChristoph Hellwig if (strcmp(name, "/dev/ram") == 0) 303*c2637e80SChristoph Hellwig return Root_RAM0; 3046d0aed7aSJens Axboe #ifdef CONFIG_BLOCK 305*c2637e80SChristoph Hellwig if (strncmp(name, "PARTUUID=", 9) == 0) 306*c2637e80SChristoph Hellwig return devt_from_partuuid(name + 9); 307*c2637e80SChristoph Hellwig if (strncmp(name, "PARTLABEL=", 10) == 0) 308*c2637e80SChristoph Hellwig return devt_from_partlabel(name + 10); 309*c2637e80SChristoph Hellwig if (strncmp(name, "/dev/", 5) == 0) 310*c2637e80SChristoph Hellwig return devt_from_devname(name + 5); 3116d0aed7aSJens Axboe #endif 312*c2637e80SChristoph Hellwig return devt_from_devnum(name); 3131da177e4SLinus Torvalds } 314e6e20a7aSDan Ehrenberg EXPORT_SYMBOL_GPL(name_to_dev_t); 3151da177e4SLinus Torvalds 3161da177e4SLinus Torvalds static int __init root_dev_setup(char *line) 3171da177e4SLinus Torvalds { 3181da177e4SLinus Torvalds strlcpy(saved_root_name, line, sizeof(saved_root_name)); 3191da177e4SLinus Torvalds return 1; 3201da177e4SLinus Torvalds } 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds __setup("root=", root_dev_setup); 3231da177e4SLinus Torvalds 324cc1ed754SPierre Ossman static int __init rootwait_setup(char *str) 325cc1ed754SPierre Ossman { 326cc1ed754SPierre Ossman if (*str) 327cc1ed754SPierre Ossman return 0; 328cc1ed754SPierre Ossman root_wait = 1; 329cc1ed754SPierre Ossman return 1; 330cc1ed754SPierre Ossman } 331cc1ed754SPierre Ossman 332cc1ed754SPierre Ossman __setup("rootwait", rootwait_setup); 333cc1ed754SPierre Ossman 3341da177e4SLinus Torvalds static char * __initdata root_mount_data; 3351da177e4SLinus Torvalds static int __init root_data_setup(char *str) 3361da177e4SLinus Torvalds { 3371da177e4SLinus Torvalds root_mount_data = str; 3381da177e4SLinus Torvalds return 1; 3391da177e4SLinus Torvalds } 3401da177e4SLinus Torvalds 3411da177e4SLinus Torvalds static char * __initdata root_fs_names; 3421da177e4SLinus Torvalds static int __init fs_names_setup(char *str) 3431da177e4SLinus Torvalds { 3441da177e4SLinus Torvalds root_fs_names = str; 3451da177e4SLinus Torvalds return 1; 3461da177e4SLinus Torvalds } 3471da177e4SLinus Torvalds 3481da177e4SLinus Torvalds static unsigned int __initdata root_delay; 3491da177e4SLinus Torvalds static int __init root_delay_setup(char *str) 3501da177e4SLinus Torvalds { 3511da177e4SLinus Torvalds root_delay = simple_strtoul(str, NULL, 0); 3521da177e4SLinus Torvalds return 1; 3531da177e4SLinus Torvalds } 3541da177e4SLinus Torvalds 3551da177e4SLinus Torvalds __setup("rootflags=", root_data_setup); 3561da177e4SLinus Torvalds __setup("rootfstype=", fs_names_setup); 3571da177e4SLinus Torvalds __setup("rootdelay=", root_delay_setup); 3581da177e4SLinus Torvalds 3591da177e4SLinus Torvalds static void __init get_fs_names(char *page) 3601da177e4SLinus Torvalds { 3611da177e4SLinus Torvalds char *s = page; 3621da177e4SLinus Torvalds 3631da177e4SLinus Torvalds if (root_fs_names) { 3641da177e4SLinus Torvalds strcpy(page, root_fs_names); 3651da177e4SLinus Torvalds while (*s++) { 3661da177e4SLinus Torvalds if (s[-1] == ',') 3671da177e4SLinus Torvalds s[-1] = '\0'; 3681da177e4SLinus Torvalds } 3691da177e4SLinus Torvalds } else { 3701da177e4SLinus Torvalds int len = get_filesystem_list(page); 3711da177e4SLinus Torvalds char *p, *next; 3721da177e4SLinus Torvalds 3731da177e4SLinus Torvalds page[len] = '\0'; 3741da177e4SLinus Torvalds for (p = page-1; p; p = next) { 3751da177e4SLinus Torvalds next = strchr(++p, '\n'); 3761da177e4SLinus Torvalds if (*p++ != '\t') 3771da177e4SLinus Torvalds continue; 3781da177e4SLinus Torvalds while ((*s++ = *p++) != '\n') 3791da177e4SLinus Torvalds ; 3801da177e4SLinus Torvalds s[-1] = '\0'; 3811da177e4SLinus Torvalds } 3821da177e4SLinus Torvalds } 3831da177e4SLinus Torvalds *s = '\0'; 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds 386cccaa5e3SDominik Brodowski static int __init do_mount_root(const char *name, const char *fs, 387cccaa5e3SDominik Brodowski const int flags, const void *data) 3881da177e4SLinus Torvalds { 389d8c9584eSAl Viro struct super_block *s; 3907de7de7cSLinus Torvalds struct page *p = NULL; 3917de7de7cSLinus Torvalds char *data_page = NULL; 392cccaa5e3SDominik Brodowski int ret; 393cccaa5e3SDominik Brodowski 3947de7de7cSLinus Torvalds if (data) { 395c60166f0SChristoph Hellwig /* init_mount() requires a full page as fifth argument */ 396cccaa5e3SDominik Brodowski p = alloc_page(GFP_KERNEL); 397cccaa5e3SDominik Brodowski if (!p) 398cccaa5e3SDominik Brodowski return -ENOMEM; 399cccaa5e3SDominik Brodowski data_page = page_address(p); 400c60166f0SChristoph Hellwig /* zero-pad. init_mount() will make sure it's terminated */ 4017de7de7cSLinus Torvalds strncpy(data_page, data, PAGE_SIZE); 4027de7de7cSLinus Torvalds } 403cccaa5e3SDominik Brodowski 404c60166f0SChristoph Hellwig ret = init_mount(name, "/root", fs, flags, data_page); 405cccaa5e3SDominik Brodowski if (ret) 406cccaa5e3SDominik Brodowski goto out; 4071da177e4SLinus Torvalds 408db63f1e3SChristoph Hellwig init_chdir("/root"); 409d8c9584eSAl Viro s = current->fs->pwd.dentry->d_sb; 410d8c9584eSAl Viro ROOT_DEV = s->s_dev; 41180cdc6daSMandeep Singh Baines printk(KERN_INFO 41280cdc6daSMandeep Singh Baines "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n", 413d8c9584eSAl Viro s->s_type->name, 414bc98a42cSDavid Howells sb_rdonly(s) ? " readonly" : "", 415d8c9584eSAl Viro MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); 416cccaa5e3SDominik Brodowski 417cccaa5e3SDominik Brodowski out: 4187de7de7cSLinus Torvalds if (p) 419cccaa5e3SDominik Brodowski put_page(p); 420cccaa5e3SDominik Brodowski return ret; 4211da177e4SLinus Torvalds } 4221da177e4SLinus Torvalds 4231da177e4SLinus Torvalds void __init mount_block_root(char *name, int flags) 4241da177e4SLinus Torvalds { 42575f296d9SLevin, Alexander (Sasha Levin) struct page *page = alloc_page(GFP_KERNEL); 426a608ca21SJeff Layton char *fs_names = page_address(page); 4271da177e4SLinus Torvalds char *p; 4281da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 4291da177e4SLinus Torvalds 430ea3edd4dSChristoph Hellwig scnprintf(b, BDEVNAME_SIZE, "unknown-block(%u,%u)", 431ea3edd4dSChristoph Hellwig MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); 4321da177e4SLinus Torvalds get_fs_names(fs_names); 4331da177e4SLinus Torvalds retry: 4341da177e4SLinus Torvalds for (p = fs_names; *p; p += strlen(p)+1) { 4351da177e4SLinus Torvalds int err = do_mount_root(name, p, flags, root_mount_data); 4361da177e4SLinus Torvalds switch (err) { 4371da177e4SLinus Torvalds case 0: 4381da177e4SLinus Torvalds goto out; 4391da177e4SLinus Torvalds case -EACCES: 4401da177e4SLinus Torvalds case -EINVAL: 4411da177e4SLinus Torvalds continue; 4421da177e4SLinus Torvalds } 4431da177e4SLinus Torvalds /* 4441da177e4SLinus Torvalds * Allow the user to distinguish between failed sys_open 4451da177e4SLinus Torvalds * and bad superblock on root device. 446dd2a345fSDave Gilbert * and give them a list of the available devices 4471da177e4SLinus Torvalds */ 4480e0cb892SBernhard Walle printk("VFS: Cannot open root device \"%s\" or %s: error %d\n", 4490e0cb892SBernhard Walle root_device_name, b, err); 450dd2a345fSDave Gilbert printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); 4511da177e4SLinus Torvalds 452dd2a345fSDave Gilbert printk_all_partitions(); 45355dc7db7STejun Heo #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT 45455dc7db7STejun Heo printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify " 45555dc7db7STejun Heo "explicit textual name for \"root=\" boot option.\n"); 45655dc7db7STejun Heo #endif 4571da177e4SLinus Torvalds panic("VFS: Unable to mount root fs on %s", b); 4581da177e4SLinus Torvalds } 459e462ec50SDavid Howells if (!(flags & SB_RDONLY)) { 460e462ec50SDavid Howells flags |= SB_RDONLY; 46110975933SMiklos Szeredi goto retry; 46210975933SMiklos Szeredi } 463be6e028bSAndy Whitcroft 464dd2a345fSDave Gilbert printk("List of all partitions:\n"); 465dd2a345fSDave Gilbert printk_all_partitions(); 466be6e028bSAndy Whitcroft printk("No filesystem could mount root, tried: "); 467be6e028bSAndy Whitcroft for (p = fs_names; *p; p += strlen(p)+1) 468be6e028bSAndy Whitcroft printk(" %s", p); 469be6e028bSAndy Whitcroft printk("\n"); 4709361401eSDavid Howells panic("VFS: Unable to mount root fs on %s", b); 4711da177e4SLinus Torvalds out: 472a608ca21SJeff Layton put_page(page); 4731da177e4SLinus Torvalds } 4741da177e4SLinus Torvalds 4751da177e4SLinus Torvalds #ifdef CONFIG_ROOT_NFS 47643717c7dSChuck Lever 47743717c7dSChuck Lever #define NFSROOT_TIMEOUT_MIN 5 47843717c7dSChuck Lever #define NFSROOT_TIMEOUT_MAX 30 47943717c7dSChuck Lever #define NFSROOT_RETRY_MAX 5 48043717c7dSChuck Lever 4811da177e4SLinus Torvalds static int __init mount_nfs_root(void) 4821da177e4SLinus Torvalds { 48356463e50SChuck Lever char *root_dev, *root_data; 48443717c7dSChuck Lever unsigned int timeout; 48543717c7dSChuck Lever int try, err; 4861da177e4SLinus Torvalds 48743717c7dSChuck Lever err = nfs_root_data(&root_dev, &root_data); 48843717c7dSChuck Lever if (err != 0) 4891da177e4SLinus Torvalds return 0; 49043717c7dSChuck Lever 49143717c7dSChuck Lever /* 49243717c7dSChuck Lever * The server or network may not be ready, so try several 49343717c7dSChuck Lever * times. Stop after a few tries in case the client wants 49443717c7dSChuck Lever * to fall back to other boot methods. 49543717c7dSChuck Lever */ 49643717c7dSChuck Lever timeout = NFSROOT_TIMEOUT_MIN; 49743717c7dSChuck Lever for (try = 1; ; try++) { 49843717c7dSChuck Lever err = do_mount_root(root_dev, "nfs", 49943717c7dSChuck Lever root_mountflags, root_data); 50043717c7dSChuck Lever if (err == 0) 50156463e50SChuck Lever return 1; 50243717c7dSChuck Lever if (try > NFSROOT_RETRY_MAX) 50343717c7dSChuck Lever break; 50443717c7dSChuck Lever 50543717c7dSChuck Lever /* Wait, in case the server refused us immediately */ 50643717c7dSChuck Lever ssleep(timeout); 50743717c7dSChuck Lever timeout <<= 1; 50843717c7dSChuck Lever if (timeout > NFSROOT_TIMEOUT_MAX) 50943717c7dSChuck Lever timeout = NFSROOT_TIMEOUT_MAX; 51043717c7dSChuck Lever } 51143717c7dSChuck Lever return 0; 5121da177e4SLinus Torvalds } 5131da177e4SLinus Torvalds #endif 5141da177e4SLinus Torvalds 5158902dd52SPaulo Alcantara (SUSE) #ifdef CONFIG_CIFS_ROOT 5168902dd52SPaulo Alcantara (SUSE) 5178902dd52SPaulo Alcantara (SUSE) extern int cifs_root_data(char **dev, char **opts); 5188902dd52SPaulo Alcantara (SUSE) 5198902dd52SPaulo Alcantara (SUSE) #define CIFSROOT_TIMEOUT_MIN 5 5208902dd52SPaulo Alcantara (SUSE) #define CIFSROOT_TIMEOUT_MAX 30 5218902dd52SPaulo Alcantara (SUSE) #define CIFSROOT_RETRY_MAX 5 5228902dd52SPaulo Alcantara (SUSE) 5238902dd52SPaulo Alcantara (SUSE) static int __init mount_cifs_root(void) 5248902dd52SPaulo Alcantara (SUSE) { 5258902dd52SPaulo Alcantara (SUSE) char *root_dev, *root_data; 5268902dd52SPaulo Alcantara (SUSE) unsigned int timeout; 5278902dd52SPaulo Alcantara (SUSE) int try, err; 5288902dd52SPaulo Alcantara (SUSE) 5298902dd52SPaulo Alcantara (SUSE) err = cifs_root_data(&root_dev, &root_data); 5308902dd52SPaulo Alcantara (SUSE) if (err != 0) 5318902dd52SPaulo Alcantara (SUSE) return 0; 5328902dd52SPaulo Alcantara (SUSE) 5338902dd52SPaulo Alcantara (SUSE) timeout = CIFSROOT_TIMEOUT_MIN; 5348902dd52SPaulo Alcantara (SUSE) for (try = 1; ; try++) { 5358902dd52SPaulo Alcantara (SUSE) err = do_mount_root(root_dev, "cifs", root_mountflags, 5368902dd52SPaulo Alcantara (SUSE) root_data); 5378902dd52SPaulo Alcantara (SUSE) if (err == 0) 5388902dd52SPaulo Alcantara (SUSE) return 1; 5398902dd52SPaulo Alcantara (SUSE) if (try > CIFSROOT_RETRY_MAX) 5408902dd52SPaulo Alcantara (SUSE) break; 5418902dd52SPaulo Alcantara (SUSE) 5428902dd52SPaulo Alcantara (SUSE) ssleep(timeout); 5438902dd52SPaulo Alcantara (SUSE) timeout <<= 1; 5448902dd52SPaulo Alcantara (SUSE) if (timeout > CIFSROOT_TIMEOUT_MAX) 5458902dd52SPaulo Alcantara (SUSE) timeout = CIFSROOT_TIMEOUT_MAX; 5468902dd52SPaulo Alcantara (SUSE) } 5478902dd52SPaulo Alcantara (SUSE) return 0; 5488902dd52SPaulo Alcantara (SUSE) } 5498902dd52SPaulo Alcantara (SUSE) #endif 5508902dd52SPaulo Alcantara (SUSE) 5511da177e4SLinus Torvalds void __init mount_root(void) 5521da177e4SLinus Torvalds { 5531da177e4SLinus Torvalds #ifdef CONFIG_ROOT_NFS 554377485f6SSasha Levin if (ROOT_DEV == Root_NFS) { 555c8376994SChristoph Hellwig if (!mount_nfs_root()) 556c8376994SChristoph Hellwig printk(KERN_ERR "VFS: Unable to mount root fs via NFS.\n"); 5571da177e4SLinus Torvalds return; 5581da177e4SLinus Torvalds } 5591da177e4SLinus Torvalds #endif 5608902dd52SPaulo Alcantara (SUSE) #ifdef CONFIG_CIFS_ROOT 5618902dd52SPaulo Alcantara (SUSE) if (ROOT_DEV == Root_CIFS) { 562c8376994SChristoph Hellwig if (!mount_cifs_root()) 563c8376994SChristoph Hellwig printk(KERN_ERR "VFS: Unable to mount root fs via SMB.\n"); 5648902dd52SPaulo Alcantara (SUSE) return; 5651da177e4SLinus Torvalds } 5661da177e4SLinus Torvalds #endif 5679361401eSDavid Howells #ifdef CONFIG_BLOCK 568c69e3c3aSVishnu Pratap Singh { 569c69e3c3aSVishnu Pratap Singh int err = create_dev("/dev/root", ROOT_DEV); 570c69e3c3aSVishnu Pratap Singh 571c69e3c3aSVishnu Pratap Singh if (err < 0) 572c69e3c3aSVishnu Pratap Singh pr_emerg("Failed to create /dev/root: %d\n", err); 5731da177e4SLinus Torvalds mount_block_root("/dev/root", root_mountflags); 574c69e3c3aSVishnu Pratap Singh } 5759361401eSDavid Howells #endif 5761da177e4SLinus Torvalds } 5771da177e4SLinus Torvalds 5781da177e4SLinus Torvalds /* 5791da177e4SLinus Torvalds * Prepare the namespace - decide what/where to mount, load ramdisks, etc. 5801da177e4SLinus Torvalds */ 5811da177e4SLinus Torvalds void __init prepare_namespace(void) 5821da177e4SLinus Torvalds { 5831da177e4SLinus Torvalds if (root_delay) { 5841da177e4SLinus Torvalds printk(KERN_INFO "Waiting %d sec before mounting root device...\n", 5851da177e4SLinus Torvalds root_delay); 5861da177e4SLinus Torvalds ssleep(root_delay); 5871da177e4SLinus Torvalds } 5881da177e4SLinus Torvalds 589216773a7SArjan van de Ven /* 590216773a7SArjan van de Ven * wait for the known devices to complete their probing 591216773a7SArjan van de Ven * 592216773a7SArjan van de Ven * Note: this is a potential source of long boot delays. 593216773a7SArjan van de Ven * For example, it is not atypical to wait 5 seconds here 594216773a7SArjan van de Ven * for the touchpad of a laptop to initialize. 595216773a7SArjan van de Ven */ 596216773a7SArjan van de Ven wait_for_device_probe(); 597d779249eSGreg Kroah-Hartman 5981da177e4SLinus Torvalds md_run_setup(); 5991da177e4SLinus Torvalds 6001da177e4SLinus Torvalds if (saved_root_name[0]) { 6011da177e4SLinus Torvalds root_device_name = saved_root_name; 6022d62f488SAdrian Hunter if (!strncmp(root_device_name, "mtd", 3) || 6032d62f488SAdrian Hunter !strncmp(root_device_name, "ubi", 3)) { 604e9482b43SJoern Engel mount_block_root(root_device_name, root_mountflags); 605e9482b43SJoern Engel goto out; 606e9482b43SJoern Engel } 6071da177e4SLinus Torvalds ROOT_DEV = name_to_dev_t(root_device_name); 6081da177e4SLinus Torvalds if (strncmp(root_device_name, "/dev/", 5) == 0) 6091da177e4SLinus Torvalds root_device_name += 5; 6101da177e4SLinus Torvalds } 6111da177e4SLinus Torvalds 6121da177e4SLinus Torvalds if (initrd_load()) 6131da177e4SLinus Torvalds goto out; 6141da177e4SLinus Torvalds 615cc1ed754SPierre Ossman /* wait for any asynchronous scanning to complete */ 616cc1ed754SPierre Ossman if ((ROOT_DEV == 0) && root_wait) { 617cc1ed754SPierre Ossman printk(KERN_INFO "Waiting for root device %s...\n", 618cc1ed754SPierre Ossman saved_root_name); 619cc1ed754SPierre Ossman while (driver_probe_done() != 0 || 620cc1ed754SPierre Ossman (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) 62139a0e975SJungseung Lee msleep(5); 622216773a7SArjan van de Ven async_synchronize_full(); 623cc1ed754SPierre Ossman } 624cc1ed754SPierre Ossman 6251da177e4SLinus Torvalds mount_root(); 6261da177e4SLinus Torvalds out: 6275e787dbfSDominik Brodowski devtmpfs_mount(); 628c60166f0SChristoph Hellwig init_mount(".", "/", NULL, MS_MOVE, NULL); 6294b7ca501SChristoph Hellwig init_chroot("."); 6301da177e4SLinus Torvalds } 63157f150a5SRob Landley 6326e19ededSRob Landley static bool is_tmpfs; 633f3235626SDavid Howells static int rootfs_init_fs_context(struct fs_context *fc) 63457f150a5SRob Landley { 6356e19ededSRob Landley if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs) 636f3235626SDavid Howells return shmem_init_fs_context(fc); 6376e19ededSRob Landley 638f3235626SDavid Howells return ramfs_init_fs_context(fc); 63957f150a5SRob Landley } 64057f150a5SRob Landley 641fd3e007fSAl Viro struct file_system_type rootfs_fs_type = { 64257f150a5SRob Landley .name = "rootfs", 643f3235626SDavid Howells .init_fs_context = rootfs_init_fs_context, 64457f150a5SRob Landley .kill_sb = kill_litter_super, 64557f150a5SRob Landley }; 64657f150a5SRob Landley 647037f11b4SAl Viro void __init init_rootfs(void) 64857f150a5SRob Landley { 6496e19ededSRob Landley if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] && 650037f11b4SAl Viro (!root_fs_names || strstr(root_fs_names, "tmpfs"))) 6516e19ededSRob Landley is_tmpfs = true; 65257f150a5SRob Landley } 653