From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- init/do_mounts.c | 674 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 674 insertions(+) create mode 100644 init/do_mounts.c (limited to 'init/do_mounts.c') diff --git a/init/do_mounts.c b/init/do_mounts.c new file mode 100644 index 000000000..2d705b9c8 --- /dev/null +++ b/init/do_mounts.c @@ -0,0 +1,674 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#include "do_mounts.h" + +int root_mountflags = MS_RDONLY | MS_SILENT; +static char * __initdata root_device_name; +static char __initdata saved_root_name[64]; +static int root_wait; + +dev_t ROOT_DEV; + +static int __init load_ramdisk(char *str) +{ + pr_warn("ignoring the deprecated load_ramdisk= option\n"); + return 1; +} +__setup("load_ramdisk=", load_ramdisk); + +static int __init readonly(char *str) +{ + if (*str) + return 0; + root_mountflags |= MS_RDONLY; + return 1; +} + +static int __init readwrite(char *str) +{ + if (*str) + return 0; + root_mountflags &= ~MS_RDONLY; + return 1; +} + +__setup("ro", readonly); +__setup("rw", readwrite); + +#ifdef CONFIG_BLOCK +struct uuidcmp { + const char *uuid; + int len; +}; + +/** + * match_dev_by_uuid - callback for finding a partition using its uuid + * @dev: device passed in by the caller + * @data: opaque pointer to the desired struct uuidcmp to match + * + * Returns 1 if the device matches, and 0 otherwise. + */ +static int match_dev_by_uuid(struct device *dev, const void *data) +{ + struct block_device *bdev = dev_to_bdev(dev); + const struct uuidcmp *cmp = data; + + if (!bdev->bd_meta_info || + strncasecmp(cmp->uuid, bdev->bd_meta_info->uuid, cmp->len)) + return 0; + return 1; +} + +/** + * devt_from_partuuid - looks up the dev_t of a partition by its UUID + * @uuid_str: char array containing ascii UUID + * + * The function will return the first partition which contains a matching + * UUID value in its partition_meta_info struct. This does not search + * by filesystem UUIDs. + * + * If @uuid_str is followed by a "/PARTNROFF=%d", then the number will be + * extracted and used as an offset from the partition identified by the UUID. + * + * Returns the matching dev_t on success or 0 on failure. + */ +static dev_t devt_from_partuuid(const char *uuid_str) +{ + struct uuidcmp cmp; + struct device *dev = NULL; + dev_t devt = 0; + int offset = 0; + char *slash; + + cmp.uuid = uuid_str; + + slash = strchr(uuid_str, '/'); + /* Check for optional partition number offset attributes. */ + if (slash) { + char c = 0; + + /* Explicitly fail on poor PARTUUID syntax. */ + if (sscanf(slash + 1, "PARTNROFF=%d%c", &offset, &c) != 1) + goto clear_root_wait; + cmp.len = slash - uuid_str; + } else { + cmp.len = strlen(uuid_str); + } + + if (!cmp.len) + goto clear_root_wait; + + dev = class_find_device(&block_class, NULL, &cmp, &match_dev_by_uuid); + if (!dev) + return 0; + + if (offset) { + /* + * Attempt to find the requested partition by adding an offset + * to the partition number found by UUID. + */ + devt = part_devt(dev_to_disk(dev), + dev_to_bdev(dev)->bd_partno + offset); + } else { + devt = dev->devt; + } + + put_device(dev); + return devt; + +clear_root_wait: + pr_err("VFS: PARTUUID= is invalid.\n" + "Expected PARTUUID=[/PARTNROFF=%%d]\n"); + if (root_wait) + pr_err("Disabling rootwait; root= is invalid.\n"); + root_wait = 0; + return 0; +} + +/** + * match_dev_by_label - callback for finding a partition using its label + * @dev: device passed in by the caller + * @data: opaque pointer to the label to match + * + * Returns 1 if the device matches, and 0 otherwise. + */ +static int match_dev_by_label(struct device *dev, const void *data) +{ + struct block_device *bdev = dev_to_bdev(dev); + const char *label = data; + + if (!bdev->bd_meta_info || strcmp(label, bdev->bd_meta_info->volname)) + return 0; + return 1; +} + +static dev_t devt_from_partlabel(const char *label) +{ + struct device *dev; + dev_t devt = 0; + + dev = class_find_device(&block_class, NULL, label, &match_dev_by_label); + if (dev) { + devt = dev->devt; + put_device(dev); + } + + return devt; +} + +static dev_t devt_from_devname(const char *name) +{ + dev_t devt = 0; + int part; + char s[32]; + char *p; + + if (strlen(name) > 31) + return 0; + strcpy(s, name); + for (p = s; *p; p++) { + if (*p == '/') + *p = '!'; + } + + devt = blk_lookup_devt(s, 0); + if (devt) + return devt; + + /* + * Try non-existent, but valid partition, which may only exist after + * opening the device, like partitioned md devices. + */ + while (p > s && isdigit(p[-1])) + p--; + if (p == s || !*p || *p == '0') + return 0; + + /* try disk name without */ + part = simple_strtoul(p, NULL, 10); + *p = '\0'; + devt = blk_lookup_devt(s, part); + if (devt) + return devt; + + /* try disk name without p */ + if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p') + return 0; + p[-1] = '\0'; + return blk_lookup_devt(s, part); +} +#endif /* CONFIG_BLOCK */ + +static dev_t devt_from_devnum(const char *name) +{ + unsigned maj, min, offset; + dev_t devt = 0; + char *p, dummy; + + if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 || + sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) { + devt = MKDEV(maj, min); + if (maj != MAJOR(devt) || min != MINOR(devt)) + return 0; + } else { + devt = new_decode_dev(simple_strtoul(name, &p, 16)); + if (*p) + return 0; + } + + return devt; +} + +/* + * Convert a name into device number. We accept the following variants: + * + * 1) device number in hexadecimal represents itself + * no leading 0x, for example b302. + * 2) /dev/nfs represents Root_NFS (0xff) + * 3) /dev/ represents the device number of disk + * 4) /dev/ represents the device number + * of partition - device number of disk plus the partition number + * 5) /dev/p - same as the above, that form is + * used when disk name of partitioned disk ends on a digit. + * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the + * unique id of a partition if the partition table provides it. + * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS + * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero- + * filled hex representation of the 32-bit "NT disk signature", and PP + * is a zero-filled hex representation of the 1-based partition number. + * 7) PARTUUID=/PARTNROFF= to select a partition in relation to + * a partition with a known unique id. + * 8) : major and minor number of the device separated by + * a colon. + * 9) PARTLABEL= with name being the GPT partition label. + * MSDOS partitions do not support labels! + * 10) /dev/cifs represents Root_CIFS (0xfe) + * + * If name doesn't have fall into the categories above, we return (0,0). + * block_class is used to check if something is a disk name. If the disk + * name contains slashes, the device name has them replaced with + * bangs. + */ +dev_t name_to_dev_t(const char *name) +{ + if (strcmp(name, "/dev/nfs") == 0) + return Root_NFS; + if (strcmp(name, "/dev/cifs") == 0) + return Root_CIFS; + if (strcmp(name, "/dev/ram") == 0) + return Root_RAM0; +#ifdef CONFIG_BLOCK + if (strncmp(name, "PARTUUID=", 9) == 0) + return devt_from_partuuid(name + 9); + if (strncmp(name, "PARTLABEL=", 10) == 0) + return devt_from_partlabel(name + 10); + if (strncmp(name, "/dev/", 5) == 0) + return devt_from_devname(name + 5); +#endif + return devt_from_devnum(name); +} +EXPORT_SYMBOL_GPL(name_to_dev_t); + +static int __init root_dev_setup(char *line) +{ + strscpy(saved_root_name, line, sizeof(saved_root_name)); + return 1; +} + +__setup("root=", root_dev_setup); + +static int __init rootwait_setup(char *str) +{ + if (*str) + return 0; + root_wait = 1; + return 1; +} + +__setup("rootwait", rootwait_setup); + +static char * __initdata root_mount_data; +static int __init root_data_setup(char *str) +{ + root_mount_data = str; + return 1; +} + +static char * __initdata root_fs_names; +static int __init fs_names_setup(char *str) +{ + root_fs_names = str; + return 1; +} + +static unsigned int __initdata root_delay; +static int __init root_delay_setup(char *str) +{ + root_delay = simple_strtoul(str, NULL, 0); + return 1; +} + +__setup("rootflags=", root_data_setup); +__setup("rootfstype=", fs_names_setup); +__setup("rootdelay=", root_delay_setup); + +/* This can return zero length strings. Caller should check */ +static int __init split_fs_names(char *page, size_t size, char *names) +{ + int count = 1; + char *p = page; + + strscpy(p, root_fs_names, size); + while (*p++) { + if (p[-1] == ',') { + p[-1] = '\0'; + count++; + } + } + + return count; +} + +static int __init do_mount_root(const char *name, const char *fs, + const int flags, const void *data) +{ + struct super_block *s; + struct page *p = NULL; + char *data_page = NULL; + int ret; + + if (data) { + /* init_mount() requires a full page as fifth argument */ + p = alloc_page(GFP_KERNEL); + if (!p) + return -ENOMEM; + data_page = page_address(p); + /* zero-pad. init_mount() will make sure it's terminated */ + strncpy(data_page, data, PAGE_SIZE); + } + + ret = init_mount(name, "/root", fs, flags, data_page); + if (ret) + goto out; + + init_chdir("/root"); + s = current->fs->pwd.dentry->d_sb; + ROOT_DEV = s->s_dev; + printk(KERN_INFO + "VFS: Mounted root (%s filesystem)%s on device %u:%u.\n", + s->s_type->name, + sb_rdonly(s) ? " readonly" : "", + MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); + +out: + if (p) + put_page(p); + return ret; +} + +void __init mount_block_root(char *name, int flags) +{ + struct page *page = alloc_page(GFP_KERNEL); + char *fs_names = page_address(page); + char *p; + char b[BDEVNAME_SIZE]; + int num_fs, i; + + scnprintf(b, BDEVNAME_SIZE, "unknown-block(%u,%u)", + MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); + if (root_fs_names) + num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names); + else + num_fs = list_bdev_fs_names(fs_names, PAGE_SIZE); +retry: + for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1) { + int err; + + if (!*p) + continue; + err = do_mount_root(name, p, flags, root_mount_data); + switch (err) { + case 0: + goto out; + case -EACCES: + case -EINVAL: + continue; + } + /* + * Allow the user to distinguish between failed sys_open + * and bad superblock on root device. + * and give them a list of the available devices + */ + printk("VFS: Cannot open root device \"%s\" or %s: error %d\n", + root_device_name, b, err); + printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); + + printk_all_partitions(); + panic("VFS: Unable to mount root fs on %s", b); + } + if (!(flags & SB_RDONLY)) { + flags |= SB_RDONLY; + goto retry; + } + + printk("List of all partitions:\n"); + printk_all_partitions(); + printk("No filesystem could mount root, tried: "); + for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1) + printk(" %s", p); + printk("\n"); + panic("VFS: Unable to mount root fs on %s", b); +out: + put_page(page); +} + +#ifdef CONFIG_ROOT_NFS + +#define NFSROOT_TIMEOUT_MIN 5 +#define NFSROOT_TIMEOUT_MAX 30 +#define NFSROOT_RETRY_MAX 5 + +static int __init mount_nfs_root(void) +{ + char *root_dev, *root_data; + unsigned int timeout; + int try, err; + + err = nfs_root_data(&root_dev, &root_data); + if (err != 0) + return 0; + + /* + * The server or network may not be ready, so try several + * times. Stop after a few tries in case the client wants + * to fall back to other boot methods. + */ + timeout = NFSROOT_TIMEOUT_MIN; + for (try = 1; ; try++) { + err = do_mount_root(root_dev, "nfs", + root_mountflags, root_data); + if (err == 0) + return 1; + if (try > NFSROOT_RETRY_MAX) + break; + + /* Wait, in case the server refused us immediately */ + ssleep(timeout); + timeout <<= 1; + if (timeout > NFSROOT_TIMEOUT_MAX) + timeout = NFSROOT_TIMEOUT_MAX; + } + return 0; +} +#endif + +#ifdef CONFIG_CIFS_ROOT + +extern int cifs_root_data(char **dev, char **opts); + +#define CIFSROOT_TIMEOUT_MIN 5 +#define CIFSROOT_TIMEOUT_MAX 30 +#define CIFSROOT_RETRY_MAX 5 + +static int __init mount_cifs_root(void) +{ + char *root_dev, *root_data; + unsigned int timeout; + int try, err; + + err = cifs_root_data(&root_dev, &root_data); + if (err != 0) + return 0; + + timeout = CIFSROOT_TIMEOUT_MIN; + for (try = 1; ; try++) { + err = do_mount_root(root_dev, "cifs", root_mountflags, + root_data); + if (err == 0) + return 1; + if (try > CIFSROOT_RETRY_MAX) + break; + + ssleep(timeout); + timeout <<= 1; + if (timeout > CIFSROOT_TIMEOUT_MAX) + timeout = CIFSROOT_TIMEOUT_MAX; + } + return 0; +} +#endif + +static bool __init fs_is_nodev(char *fstype) +{ + struct file_system_type *fs = get_fs_type(fstype); + bool ret = false; + + if (fs) { + ret = !(fs->fs_flags & FS_REQUIRES_DEV); + put_filesystem(fs); + } + + return ret; +} + +static int __init mount_nodev_root(void) +{ + char *fs_names, *fstype; + int err = -EINVAL; + int num_fs, i; + + fs_names = (void *)__get_free_page(GFP_KERNEL); + if (!fs_names) + return -EINVAL; + num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names); + + for (i = 0, fstype = fs_names; i < num_fs; + i++, fstype += strlen(fstype) + 1) { + if (!*fstype) + continue; + if (!fs_is_nodev(fstype)) + continue; + err = do_mount_root(root_device_name, fstype, root_mountflags, + root_mount_data); + if (!err) + break; + } + + free_page((unsigned long)fs_names); + return err; +} + +void __init mount_root(void) +{ +#ifdef CONFIG_ROOT_NFS + if (ROOT_DEV == Root_NFS) { + if (!mount_nfs_root()) + printk(KERN_ERR "VFS: Unable to mount root fs via NFS.\n"); + return; + } +#endif +#ifdef CONFIG_CIFS_ROOT + if (ROOT_DEV == Root_CIFS) { + if (!mount_cifs_root()) + printk(KERN_ERR "VFS: Unable to mount root fs via SMB.\n"); + return; + } +#endif + if (ROOT_DEV == 0 && root_device_name && root_fs_names) { + if (mount_nodev_root() == 0) + return; + } +#ifdef CONFIG_BLOCK + { + int err = create_dev("/dev/root", ROOT_DEV); + + if (err < 0) + pr_emerg("Failed to create /dev/root: %d\n", err); + mount_block_root("/dev/root", root_mountflags); + } +#endif +} + +/* + * Prepare the namespace - decide what/where to mount, load ramdisks, etc. + */ +void __init prepare_namespace(void) +{ + if (root_delay) { + printk(KERN_INFO "Waiting %d sec before mounting root device...\n", + root_delay); + ssleep(root_delay); + } + + /* + * wait for the known devices to complete their probing + * + * Note: this is a potential source of long boot delays. + * For example, it is not atypical to wait 5 seconds here + * for the touchpad of a laptop to initialize. + */ + wait_for_device_probe(); + + md_run_setup(); + + if (saved_root_name[0]) { + root_device_name = saved_root_name; + if (!strncmp(root_device_name, "mtd", 3) || + !strncmp(root_device_name, "ubi", 3)) { + mount_block_root(root_device_name, root_mountflags); + goto out; + } + ROOT_DEV = name_to_dev_t(root_device_name); + if (strncmp(root_device_name, "/dev/", 5) == 0) + root_device_name += 5; + } + + if (initrd_load()) + goto out; + + /* wait for any asynchronous scanning to complete */ + if ((ROOT_DEV == 0) && root_wait) { + printk(KERN_INFO "Waiting for root device %s...\n", + saved_root_name); + while (driver_probe_done() != 0 || + (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) + msleep(5); + async_synchronize_full(); + } + + mount_root(); +out: + devtmpfs_mount(); + init_mount(".", "/", NULL, MS_MOVE, NULL); + init_chroot("."); +} + +static bool is_tmpfs; +static int rootfs_init_fs_context(struct fs_context *fc) +{ + if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs) + return shmem_init_fs_context(fc); + + return ramfs_init_fs_context(fc); +} + +struct file_system_type rootfs_fs_type = { + .name = "rootfs", + .init_fs_context = rootfs_init_fs_context, + .kill_sb = kill_litter_super, +}; + +void __init init_rootfs(void) +{ + if (IS_ENABLED(CONFIG_TMPFS)) { + if (!saved_root_name[0] && !root_fs_names) + is_tmpfs = true; + else if (root_fs_names && !!strstr(root_fs_names, "tmpfs")) + is_tmpfs = true; + } +} -- cgit v1.2.3