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Diffstat (limited to 'init/do_mounts.c')
-rw-r--r--init/do_mounts.c141
1 files changed, 109 insertions, 32 deletions
diff --git a/init/do_mounts.c b/init/do_mounts.c
index 2974c8b3b35..82f22885c87 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -1,3 +1,13 @@
+/*
+ * Many of the syscalls used in this file expect some of the arguments
+ * to be __user pointers not __kernel pointers. To limit the sparse
+ * noise, turn off sparse checking for this file.
+ */
+#ifdef __CHECKER__
+#undef __CHECKER__
+#warning "Sparse checking disabled for this file"
+#endif
+
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/ctype.h>
@@ -16,6 +26,8 @@
#include <linux/async.h>
#include <linux/fs_struct.h>
#include <linux/slab.h>
+#include <linux/ramfs.h>
+#include <linux/shmem_fs.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_fs_sb.h>
@@ -59,23 +71,28 @@ __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 a 36 byte char array with a UUID
+ * @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, void *data)
+static int match_dev_by_uuid(struct device *dev, const void *data)
{
- u8 *uuid = data;
+ const struct uuidcmp *cmp = 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;
+ if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
+ goto no_match;
return 1;
no_match:
@@ -85,49 +102,52 @@ no_match:
/**
* 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
+ * @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 is followed by a "/PARTNROFF=%d", then the number will be
+ * 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(char *uuid_str)
+static dev_t devt_from_partuuid(const char *uuid_str)
{
dev_t res = 0;
+ struct uuidcmp cmp;
struct device *dev = NULL;
- u8 uuid[16];
struct gendisk *disk;
struct hd_struct *part;
int offset = 0;
+ bool clear_root_wait = false;
+ char *slash;
- if (strlen(uuid_str) < 36)
- goto done;
+ cmp.uuid = uuid_str;
+ slash = strchr(uuid_str, '/');
/* Check for optional partition number offset attributes. */
- if (uuid_str[36]) {
+ if (slash) {
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=<valid-uuid-id>[/PARTNROFF=%%d]\n");
- if (root_wait)
- printk(KERN_ERR
- "Disabling rootwait; root= is invalid.\n");
- root_wait = 0;
+ if (sscanf(slash + 1,
+ "PARTNROFF=%d%c", &offset, &c) != 1) {
+ clear_root_wait = true;
goto done;
}
+ cmp.len = slash - uuid_str;
+ } else {
+ cmp.len = strlen(uuid_str);
}
- /* Pack the requested UUID in the expected format. */
- part_pack_uuid(uuid_str, uuid);
+ if (!cmp.len) {
+ clear_root_wait = true;
+ goto done;
+ }
- dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid);
+ dev = class_find_device(&block_class, NULL, &cmp,
+ &match_dev_by_uuid);
if (!dev)
goto done;
@@ -148,6 +168,13 @@ static dev_t devt_from_partuuid(char *uuid_str)
no_offset:
put_device(dev);
done:
+ if (clear_root_wait) {
+ pr_err("VFS: PARTUUID= is invalid.\n"
+ "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
+ if (root_wait)
+ pr_err("Disabling rootwait; root= is invalid.\n");
+ root_wait = 0;
+ }
return res;
}
#endif
@@ -164,8 +191,14 @@ done:
* 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=<UUID>/PARTNROFF=<int> to select a partition in relation to
* a partition with a known unique id.
+ * 8) <major>:<minor> major and minor number of the device separated by
+ * a colon.
*
* 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
@@ -330,7 +363,7 @@ static int __init do_mount_root(char *name, char *fs, int flags, void *data)
if (err)
return err;
- sys_chdir((const char __user __force *)"/root");
+ sys_chdir("/root");
s = current->fs->pwd.dentry->d_sb;
ROOT_DEV = s->s_dev;
printk(KERN_INFO
@@ -343,8 +376,9 @@ static int __init do_mount_root(char *name, char *fs, int flags, void *data)
void __init mount_block_root(char *name, int flags)
{
- char *fs_names = __getname_gfp(GFP_KERNEL
- | __GFP_NOTRACK_FALSE_POSITIVE);
+ struct page *page = alloc_page(GFP_KERNEL |
+ __GFP_NOTRACK_FALSE_POSITIVE);
+ char *fs_names = page_address(page);
char *p;
#ifdef CONFIG_BLOCK
char b[BDEVNAME_SIZE];
@@ -373,8 +407,8 @@ 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();
@@ -396,7 +430,7 @@ retry:
#endif
panic("VFS: Unable to mount root fs on %s", b);
out:
- putname(fs_names);
+ put_page(page);
}
#ifdef CONFIG_ROOT_NFS
@@ -472,7 +506,7 @@ void __init change_floppy(char *fmt, ...)
void __init mount_root(void)
{
#ifdef CONFIG_ROOT_NFS
- if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
+ if (ROOT_DEV == Root_NFS) {
if (mount_nfs_root())
return;
@@ -506,7 +540,7 @@ void __init prepare_namespace(void)
int is_floppy;
if (root_delay) {
- printk(KERN_INFO "Waiting %dsec before mounting root device...\n",
+ printk(KERN_INFO "Waiting %d sec before mounting root device...\n",
root_delay);
ssleep(root_delay);
}
@@ -556,5 +590,48 @@ void __init prepare_namespace(void)
out:
devtmpfs_mount("dev");
sys_mount(".", "/", NULL, MS_MOVE, NULL);
- sys_chroot((const char __user __force *)".");
+ sys_chroot(".");
+}
+
+static bool is_tmpfs;
+static struct dentry *rootfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ static unsigned long once;
+ void *fill = ramfs_fill_super;
+
+ if (test_and_set_bit(0, &once))
+ return ERR_PTR(-ENODEV);
+
+ if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
+ fill = shmem_fill_super;
+
+ return mount_nodev(fs_type, flags, data, fill);
+}
+
+static struct file_system_type rootfs_fs_type = {
+ .name = "rootfs",
+ .mount = rootfs_mount,
+ .kill_sb = kill_litter_super,
+};
+
+int __init init_rootfs(void)
+{
+ int err = register_filesystem(&rootfs_fs_type);
+
+ if (err)
+ return err;
+
+ if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
+ (!root_fs_names || strstr(root_fs_names, "tmpfs"))) {
+ err = shmem_init();
+ is_tmpfs = true;
+ } else {
+ err = init_ramfs_fs();
+ }
+
+ if (err)
+ unregister_filesystem(&rootfs_fs_type);
+
+ return err;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 22:55:32 +0000