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-rw-r--r--usr/kinit/do_mounts.c533
1 files changed, 533 insertions, 0 deletions
diff --git a/usr/kinit/do_mounts.c b/usr/kinit/do_mounts.c
new file mode 100644
index 0000000..b648299
--- /dev/null
+++ b/usr/kinit/do_mounts.c
@@ -0,0 +1,533 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <mntent.h>
+
+#include "do_mounts.h"
+#include "kinit.h"
+#include "fstype.h"
+#include "zlib.h"
+
+#ifndef MS_RELATIME
+# define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */
+#endif
+
+#ifndef MS_STRICTATIME
+# define MS_STRICTATIME (1<<24) /* Always perform atime updates */
+#endif
+
+/*
+ * The following mount option parsing was stolen from
+ *
+ * usr/utils/mount_opts.c
+ *
+ * and adapted to add some later mount flags.
+ */
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
+
+struct mount_opts {
+ const char str[16];
+ unsigned long rwmask;
+ unsigned long rwset;
+ unsigned long rwnoset;
+};
+
+struct extra_opts {
+ char *str;
+ char *end;
+ int used_size;
+ int alloc_size;
+};
+
+/*
+ * These options define the function of "mount(2)".
+ */
+#define MS_TYPE (MS_REMOUNT|MS_BIND|MS_MOVE)
+
+
+/* These must be in alphabetic order! */
+static const struct mount_opts options[] = {
+ /* name mask set noset */
+ {"async", MS_SYNCHRONOUS, 0, MS_SYNCHRONOUS},
+ {"atime", MS_NOATIME, 0, MS_NOATIME},
+ {"bind", MS_TYPE, MS_BIND, 0,},
+ {"dev", MS_NODEV, 0, MS_NODEV},
+ {"diratime", MS_NODIRATIME, 0, MS_NODIRATIME},
+ {"dirsync", MS_DIRSYNC, MS_DIRSYNC, 0},
+ {"exec", MS_NOEXEC, 0, MS_NOEXEC},
+ {"move", MS_TYPE, MS_MOVE, 0},
+ {"nodev", MS_NODEV, MS_NODEV, 0},
+ {"noexec", MS_NOEXEC, MS_NOEXEC, 0},
+ {"nosuid", MS_NOSUID, MS_NOSUID, 0},
+ {"recurse", MS_REC, MS_REC, 0},
+ {"relatime", MS_RELATIME, MS_RELATIME, 0},
+ {"remount", MS_TYPE, MS_REMOUNT, 0},
+ {"ro", MS_RDONLY, MS_RDONLY, 0},
+ {"rw", MS_RDONLY, 0, MS_RDONLY},
+ {"strictatime", MS_STRICTATIME, MS_STRICTATIME, 0},
+ {"suid", MS_NOSUID, 0, MS_NOSUID},
+ {"sync", MS_SYNCHRONOUS, MS_SYNCHRONOUS, 0},
+ {"verbose", MS_VERBOSE, MS_VERBOSE, 0},
+};
+
+/*
+ * Append 's' to 'extra->str'. 's' is a mount option that can't be turned into
+ * a flag. Return 0 on success, -1 on error.
+ */
+static int add_extra_option(struct extra_opts *extra, char *s)
+{
+ int len = strlen(s);
+ int newlen = extra->used_size + len;
+
+ if (extra->str)
+ len++; /* +1 for ',' */
+
+ if (newlen >= extra->alloc_size) {
+ char *new;
+
+ new = realloc(extra->str, newlen + 1); /* +1 for NUL */
+ if (!new) {
+ if (extra->str)
+ free(extra->str);
+ return -1;
+ }
+
+ extra->str = new;
+ extra->end = extra->str + extra->used_size;
+ extra->alloc_size = newlen;
+ }
+
+ if (extra->used_size) {
+ *extra->end = ',';
+ extra->end++;
+ }
+ strcpy(extra->end, s);
+ extra->used_size += len;
+
+ return 0;
+}
+
+/*
+ * Parse the options in 'arg'; put numeric mount flags into 'flags' and
+ * the rest into 'extra'. Return 0 on success, -1 on error.
+ */
+static int
+parse_mount_options(char *arg, unsigned long *flags, struct extra_opts *extra)
+{
+ char *s;
+
+ while ((s = strsep(&arg, ",")) != NULL) {
+ char *opt = s;
+ unsigned int i;
+ int res;
+ int no = (s[0] == 'n' && s[1] == 'o');
+ int found = 0;
+
+ if (no)
+ s += 2;
+
+ for (i = 0; i < ARRAY_SIZE(options); i++) {
+
+ res = strcmp(s, options[i].str);
+ if (res == 0) {
+ found = 1;
+ *flags &= ~options[i].rwmask;
+ if (no)
+ *flags |= options[i].rwnoset;
+ else
+ *flags |= options[i].rwset;
+ break;
+
+ /* If we're beyond 's' alphabetically, we're done */
+ } else if (res < 0)
+ break;
+ }
+ if (! found)
+ if (add_extra_option(extra, opt) != 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Create the device node "name" */
+int create_dev(const char *name, dev_t dev)
+{
+ unlink(name);
+ return mknod(name, S_IFBLK | 0600, dev);
+}
+
+
+/*
+ * If there is not a block device for the input 'name', try to create one; if
+ * we can't that's okay.
+ */
+static void create_dev_if_not_present(const char *name)
+{
+ struct stat st;
+ dev_t dev;
+
+ if (stat(name, &st) == 0) /* file present; we're done */
+ return;
+ dev = name_to_dev_t(name);
+ if (dev)
+ (void) create_dev(name, dev);
+}
+
+
+/* mount a filesystem, possibly trying a set of different types */
+const char *mount_block(const char *source, const char *target,
+ const char *type, unsigned long flags,
+ const void *data)
+{
+ char *fslist, *p, *ep;
+ const char *rp;
+ ssize_t fsbytes;
+ int fd;
+
+ if (type) {
+ dprintf("kinit: trying to mount %s on %s "
+ "with type %s, flags 0x%lx, data '%s'\n",
+ source, target, type, flags, (char *)data);
+ int rv = mount(source, target, type, flags, data);
+
+ if (rv != 0)
+ dprintf("kinit: mount %s on %s failed "
+ "with errno = %d\n",
+ source, target, errno);
+ /* Mount readonly if necessary */
+ if (rv == -1 && errno == EACCES && !(flags & MS_RDONLY))
+ rv = mount(source, target, type, flags | MS_RDONLY,
+ data);
+ return rv ? NULL : type;
+ }
+
+ /* If no type given, try to identify the type first; this
+ also takes care of specific ordering requirements, like
+ ext3 before ext2... */
+ fd = open(source, O_RDONLY);
+ if (fd >= 0) {
+ int err = identify_fs(fd, &type, NULL, 0);
+ close(fd);
+
+ if (!err && type) {
+ dprintf("kinit: %s appears to be a %s filesystem\n",
+ source, type);
+ type = mount_block(source, target, type, flags, data);
+ if (type)
+ return type;
+ }
+ }
+
+ dprintf("kinit: failed to identify filesystem %s, trying all\n",
+ source);
+
+ fsbytes = readfile("/proc/filesystems", &fslist);
+
+ errno = EINVAL;
+ if (fsbytes < 0)
+ return NULL;
+
+ p = fslist;
+ ep = fslist + fsbytes;
+
+ rp = NULL;
+
+ while (p < ep) {
+ type = p;
+ p = strchr(p, '\n');
+ if (!p)
+ break;
+ *p++ = '\0';
+ /* We can't mount a block device as a "nodev" fs */
+ if (*type != '\t')
+ continue;
+
+ type++;
+ rp = mount_block(source, target, type, flags, data);
+ if (rp)
+ break;
+ if (errno != EINVAL)
+ break;
+ }
+
+ free(fslist);
+ return rp;
+}
+
+/* mount the root filesystem from a block device */
+static int
+mount_block_root(int argc, char *argv[], dev_t root_dev,
+ const char *type, unsigned long flags)
+{
+ const char *data, *rp;
+
+ data = get_arg(argc, argv, "rootflags=");
+ create_dev("/dev/root", root_dev);
+
+ errno = 0;
+
+ if (type) {
+ if ((rp = mount_block("/dev/root", "/root", type, flags, data)))
+ goto ok;
+ if (errno != EINVAL)
+ goto bad;
+ }
+
+ if (!errno
+ && (rp = mount_block("/dev/root", "/root", NULL, flags, data)))
+ goto ok;
+
+bad:
+ if (errno != EINVAL) {
+ /*
+ * Allow the user to distinguish between failed open
+ * and bad superblock on root device.
+ */
+ fprintf(stderr, "%s: Cannot open root device %s\n",
+ progname, bdevname(root_dev));
+ return -errno;
+ } else {
+ fprintf(stderr, "%s: Unable to mount root fs on device %s\n",
+ progname, bdevname(root_dev));
+ return -ESRCH;
+ }
+
+ok:
+ printf("%s: Mounted root (%s filesystem)%s.\n",
+ progname, rp, (flags & MS_RDONLY) ? " readonly" : "");
+ return 0;
+}
+
+static int
+mount_roots(int argc, char *argv[], const char *root_dev_name)
+{
+ char *roots = strdup(root_dev_name);
+ char *root;
+ const char *sep = ",";
+ char *saveptr;
+ int ret = -ESRCH;
+
+ root = strtok_r(roots, sep, &saveptr);
+ while (root) {
+ dev_t root_dev;
+
+ dprintf("kinit: trying to mount %s\n", root);
+ root_dev = name_to_dev_t(root);
+ ret = mount_root(argc, argv, root_dev, root);
+ if (!ret)
+ break;
+ root = strtok_r(NULL, sep, &saveptr);
+ }
+ free(roots);
+ return ret;
+}
+
+int
+mount_root(int argc, char *argv[], dev_t root_dev, const char *root_dev_name)
+{
+ unsigned long flags = MS_RDONLY | MS_VERBOSE;
+ int ret;
+ const char *type = get_arg(argc, argv, "rootfstype=");
+
+ if (get_flag(argc, argv, "rw") > get_flag(argc, argv, "ro")) {
+ dprintf("kinit: mounting root rw\n");
+ flags &= ~MS_RDONLY;
+ }
+
+ if (type) {
+ if (!strcmp(type, "nfs"))
+ root_dev = Root_NFS;
+ else if (!strcmp(type, "jffs2") && !major(root_dev))
+ root_dev = Root_MTD;
+ }
+
+ switch (root_dev) {
+ case Root_NFS:
+ ret = mount_nfs_root(argc, argv, flags);
+ break;
+ case Root_MTD:
+ ret = mount_mtd_root(argc, argv, root_dev_name, type, flags);
+ break;
+ default:
+ ret = mount_block_root(argc, argv, root_dev, type, flags);
+ break;
+ }
+
+ if (!ret)
+ chdir("/root");
+
+ return ret;
+}
+
+/* Allocate a buffer and prepend '/root' onto 'src'. */
+static char *prepend_root_dir(const char *src)
+{
+ size_t len = strlen(src) + 6; /* "/root" */
+ char *p = malloc(len);
+
+ if (!p)
+ return NULL;
+
+ strcpy(p, "/root");
+ strcat(p, src);
+ return p;
+}
+
+int do_cmdline_mounts(int argc, char *argv[])
+{
+ int arg_i;
+ int ret = 0;
+
+ for (arg_i = 0; arg_i < argc; arg_i++) {
+ const char *fs_dev, *fs_dir, *fs_type;
+ char *fs_opts;
+ unsigned long flags = 0;
+ char *saveptr = NULL;
+ char *new_dir;
+ struct extra_opts extra = { 0, 0, 0, 0 };
+
+ if (strncmp(argv[arg_i], "kinit_mount=", 12))
+ continue;
+ /*
+ * Format:
+ * <fs_dev>;<dir>;<fs_type>;[opt1],[optn...]
+ */
+ fs_dev = strtok_r(&argv[arg_i][12], ";", &saveptr);
+ if (!fs_dev) {
+ fprintf(stderr, "Failed to parse fs_dev\n");
+ continue;
+ }
+ fs_dir = strtok_r(NULL, ";", &saveptr);
+ if (!fs_dir) {
+ fprintf(stderr, "Failed to parse fs_dir\n");
+ continue;
+ }
+ fs_type = strtok_r(NULL, ";", &saveptr);
+ if (!fs_type) {
+ fprintf(stderr, "Failed to parse fs_type\n");
+ continue;
+ }
+ fs_opts = strtok_r(NULL, ";", &saveptr);
+ /* Don't error if there is no option string sent */
+
+ new_dir = prepend_root_dir(fs_dir);
+ if (! new_dir)
+ return -ENOMEM;
+ create_dev_if_not_present(fs_dev);
+ ret = parse_mount_options(fs_opts, &flags, &extra);
+ if (ret != 0)
+ break;
+
+ if (!mount_block(fs_dev, new_dir, fs_type,
+ flags, extra.str))
+ fprintf(stderr, "Skipping failed mount '%s'\n", fs_dev);
+ free(new_dir);
+ if (extra.str)
+ free(extra.str);
+ }
+ return ret;
+}
+
+int do_fstab_mounts(FILE *fp)
+{
+ struct mntent *ent = NULL;
+ char *new_dir;
+ int ret = 0;
+
+ while ((ent = getmntent(fp))) {
+ unsigned long flags = 0;
+ struct extra_opts extra = { 0, 0, 0, 0 };
+
+ new_dir = prepend_root_dir(ent->mnt_dir);
+ if (! new_dir)
+ return -ENOMEM;
+ create_dev_if_not_present(ent->mnt_fsname);
+ ret = parse_mount_options(ent->mnt_opts, &flags, &extra);
+ if (ret != 0)
+ break;
+
+ if (!mount_block(ent->mnt_fsname,
+ new_dir,
+ ent->mnt_type,
+ flags,
+ extra.str)) {
+ fprintf(stderr, "Skipping failed mount '%s'\n",
+ ent->mnt_fsname);
+ }
+ free(new_dir);
+ if (extra.str)
+ free(extra.str);
+ }
+ return 0;
+}
+
+int do_mounts(int argc, char *argv[])
+{
+ const char *root_dev_name = get_arg(argc, argv, "root=");
+ const char *root_delay = get_arg(argc, argv, "rootdelay=");
+ const char *load_ramdisk = get_arg(argc, argv, "load_ramdisk=");
+ dev_t root_dev = 0;
+ int err;
+ FILE *fp;
+
+ dprintf("kinit: do_mounts\n");
+
+ if (root_delay) {
+ int delay = atoi(root_delay);
+ fprintf(stderr, "Waiting %d s before mounting root device...\n",
+ delay);
+ sleep(delay);
+ }
+
+ md_run(argc, argv);
+
+ if (root_dev_name) {
+ root_dev = name_to_dev_t(root_dev_name);
+ } else if (get_arg(argc, argv, "nfsroot=") ||
+ get_arg(argc, argv, "nfsaddrs=")) {
+ root_dev = Root_NFS;
+ } else {
+ long rootdev;
+ getintfile("/proc/sys/kernel/real-root-dev", &rootdev);
+ root_dev = (dev_t) rootdev;
+ }
+
+ dprintf("kinit: root_dev = %s\n", bdevname(root_dev));
+
+ if (initrd_load(argc, argv, root_dev)) {
+ dprintf("initrd loaded\n");
+ return 0;
+ }
+
+ if (load_ramdisk && atoi(load_ramdisk)) {
+ if (ramdisk_load(argc, argv))
+ root_dev = Root_RAM0;
+ }
+
+ if (root_dev == Root_MULTI)
+ err = mount_roots(argc, argv, root_dev_name);
+ else
+ err = mount_root(argc, argv, root_dev, root_dev_name);
+
+ if (err)
+ return err;
+
+ if ((fp = setmntent("/etc/fstab", "r"))) {
+ err = do_fstab_mounts(fp);
+ fclose(fp);
+ }
+
+ if (err)
+ return err;
+
+ if (get_arg(argc, argv, "kinit_mount="))
+ err = do_cmdline_mounts(argc, argv);
+ return err;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-10 22:21:41 +0000