X-Git-Url: https://nv-tegra.nvidia.com/r/gitweb?p=linux-3.10.git;a=blobdiff_plain;f=init%2Fdo_mounts.c;h=0e93f92a0345a09a2aa84608a3bca34153a2eabb;hp=d055b1914c3d3b696237a04bb352ed5dbb7e14c6;hb=dcb0f22282e680ee5202ab7574ce78beb3803a9f;hpb=55dc7db70a73a3809a2334063c9b5b0d8ccebdaa diff --git a/init/do_mounts.c b/init/do_mounts.c index d055b1914c3..0e93f92a034 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -13,6 +13,9 @@ #include #include #include +#include +#include +#include #include #include @@ -25,7 +28,7 @@ int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */ int root_mountflags = MS_RDONLY | MS_SILENT; static char * __initdata root_device_name; static char __initdata saved_root_name[64]; -static int __initdata root_wait; +static int root_wait; dev_t ROOT_DEV; @@ -55,6 +58,100 @@ static int __init readwrite(char *str) __setup("ro", readonly); __setup("rw", readwrite); +#ifdef CONFIG_BLOCK +/** + * match_dev_by_uuid - callback for finding a partition using its uuid + * @dev: device passed in by the caller + * @data: opaque pointer to a 36 byte char array with a UUID + * + * Returns 1 if the device matches, and 0 otherwise. + */ +static int match_dev_by_uuid(struct device *dev, void *data) +{ + u8 *uuid = data; + struct hd_struct *part = dev_to_part(dev); + + if (!part->info) + goto no_match; + + if (memcmp(uuid, part->info->uuid, sizeof(part->info->uuid))) + goto no_match; + + return 1; +no_match: + return 0; +} + + +/** + * devt_from_partuuid - looks up the dev_t of a partition by its UUID + * @uuid: min 36 byte char array containing a hex 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 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(char *uuid_str) +{ + dev_t res = 0; + struct device *dev = NULL; + u8 uuid[16]; + struct gendisk *disk; + struct hd_struct *part; + int offset = 0; + + if (strlen(uuid_str) < 36) + goto done; + + /* Check for optional partition number offset attributes. */ + if (uuid_str[36]) { + char c = 0; + /* Explicitly fail on poor PARTUUID syntax. */ + if (sscanf(&uuid_str[36], + "/PARTNROFF=%d%c", &offset, &c) != 1) { + printk(KERN_ERR "VFS: PARTUUID= is invalid.\n" + "Expected PARTUUID=[/PARTNROFF=%%d]\n"); + if (root_wait) + printk(KERN_ERR + "Disabling rootwait; root= is invalid.\n"); + root_wait = 0; + goto done; + } + } + + /* Pack the requested UUID in the expected format. */ + part_pack_uuid(uuid_str, uuid); + + dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid); + if (!dev) + goto done; + + res = dev->devt; + + /* Attempt to find the partition by offset. */ + if (!offset) + goto no_offset; + + res = 0; + disk = part_to_disk(dev_to_part(dev)); + part = disk_get_part(disk, dev_to_part(dev)->partno + offset); + if (part) { + res = part_devt(part); + put_device(part_to_dev(part)); + } + +no_offset: + put_device(dev); +done: + return res; +} +#endif + /* * Convert a name into device number. We accept the following variants: * @@ -65,6 +162,10 @@ __setup("rw", readwrite); * 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. + * 7) PARTUUID=/PARTNROFF= to select a partition in relation to + * a partition with a known unique id. * * 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 @@ -79,6 +180,16 @@ dev_t name_to_dev_t(char *name) dev_t res = 0; int part; +#ifdef CONFIG_BLOCK + if (strncmp(name, "PARTUUID=", 9) == 0) { + name += 9; + res = devt_from_partuuid(name); + if (!res) + goto fail; + goto done; + } +#endif + if (strncmp(name, "/dev/", 5) != 0) { unsigned maj, min; @@ -113,7 +224,7 @@ dev_t name_to_dev_t(char *name) goto done; /* - * try non-existant, but valid partition, which may only exist + * try non-existent, but valid partition, which may only exist * after revalidating the disk, like partitioned md devices */ while (p > s && isdigit(p[-1])) @@ -214,22 +325,26 @@ static void __init get_fs_names(char *page) static int __init do_mount_root(char *name, char *fs, int flags, void *data) { + struct super_block *s; int err = sys_mount(name, "/root", fs, flags, data); if (err) return err; - sys_chdir("/root"); - ROOT_DEV = current->fs->pwd.mnt->mnt_sb->s_dev; - printk("VFS: Mounted root (%s filesystem)%s.\n", - current->fs->pwd.mnt->mnt_sb->s_type->name, - current->fs->pwd.mnt->mnt_sb->s_flags & MS_RDONLY ? - " readonly" : ""); + sys_chdir((const char __user __force *)"/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, + s->s_flags & MS_RDONLY ? " readonly" : "", + MAJOR(ROOT_DEV), MINOR(ROOT_DEV)); return 0; } void __init mount_block_root(char *name, int flags) { - char *fs_names = __getname(); + char *fs_names = __getname_gfp(GFP_KERNEL + | __GFP_NOTRACK_FALSE_POSITIVE); char *p; #ifdef CONFIG_BLOCK char b[BDEVNAME_SIZE]; @@ -258,8 +373,8 @@ retry: #ifdef CONFIG_BLOCK __bdevname(ROOT_DEV, b); #endif - printk("VFS: Cannot open root device \"%s\" or %s\n", - root_device_name, b); + 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(); @@ -285,14 +400,41 @@ out: } #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) { - void *data = nfs_root_data(); + char *root_dev, *root_data; + unsigned int timeout; + int try, err; - create_dev("/dev/root", ROOT_DEV); - if (data && - do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0) - return 1; + 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 @@ -369,9 +511,14 @@ void __init prepare_namespace(void) ssleep(root_delay); } - /* wait for the known devices to complete their probing */ - while (driver_probe_done() != 0) - msleep(100); + /* + * 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(); @@ -397,6 +544,7 @@ void __init prepare_namespace(void) while (driver_probe_done() != 0 || (ROOT_DEV = name_to_dev_t(saved_root_name)) == 0) msleep(100); + async_synchronize_full(); } is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR; @@ -406,7 +554,7 @@ void __init prepare_namespace(void) mount_root(); out: + devtmpfs_mount("dev"); sys_mount(".", "/", NULL, MS_MOVE, NULL); - sys_chroot("."); + sys_chroot((const char __user __force *)"."); } -