Merge branch 'hch.init_path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull init and set_fs() cleanups from Al Viro:
 "Christoph's 'getting rid of ksys_...() uses under KERNEL_DS' series"

* 'hch.init_path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (50 commits)
  init: add an init_dup helper
  init: add an init_utimes helper
  init: add an init_stat helper
  init: add an init_mknod helper
  init: add an init_mkdir helper
  init: add an init_symlink helper
  init: add an init_link helper
  init: add an init_eaccess helper
  init: add an init_chmod helper
  init: add an init_chown helper
  init: add an init_chroot helper
  init: add an init_chdir helper
  init: add an init_rmdir helper
  init: add an init_unlink helper
  init: add an init_umount helper
  init: add an init_mount helper
  init: mark create_dev as __init
  init: mark console_on_rootfs as __init
  init: initialize ramdisk_execute_command at compile time
  devtmpfs: refactor devtmpfsd()
  ...

35 files changed, 796 insertions, 768 deletions

diff --git a/arch/arm/kernel/atags_parse.c b/arch/arm/kernel/atags_parse.c
index ce02f92f4ab2..6c12d9fe694e 100644
--- a/arch/arm/kernel/atags_parse.c
+++ b/arch/arm/kernel/atags_parse.c
@@ -91,8 +91,6 @@ __tagtable(ATAG_VIDEOTEXT, parse_tag_videotext);
 static int __init parse_tag_ramdisk(const struct tag *tag)
 {
 	rd_image_start = tag->u.ramdisk.start;
-	rd_doload = (tag->u.ramdisk.flags & 1) == 0;
-	rd_prompt = (tag->u.ramdisk.flags & 2) == 0;
 
 	if (tag->u.ramdisk.size)
 		rd_size = tag->u.ramdisk.size;
diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index 67f5a3b44c2e..4144be650d41 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -290,8 +290,6 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_BLK_DEV_RAM
 	rd_image_start = RAMDISK_FLAGS & RAMDISK_IMAGE_START_MASK;
-	rd_prompt = ((RAMDISK_FLAGS & RAMDISK_PROMPT_FLAG) != 0);
-	rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
 #endif
 
 	if (!MOUNT_ROOT_RDONLY)
diff --git a/arch/sparc/kernel/setup_32.c b/arch/sparc/kernel/setup_32.c
index 6d07b85b9e24..eea43a1aef1b 100644
--- a/arch/sparc/kernel/setup_32.c
+++ b/arch/sparc/kernel/setup_32.c
@@ -353,8 +353,6 @@ void __init setup_arch(char **cmdline_p)
 	ROOT_DEV = old_decode_dev(root_dev);
 #ifdef CONFIG_BLK_DEV_RAM
 	rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
-	rd_prompt = ((ram_flags & RAMDISK_PROMPT_FLAG) != 0);
-	rd_doload = ((ram_flags & RAMDISK_LOAD_FLAG) != 0);	
 #endif
 
 	prom_setsync(prom_sync_me);
diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
index f765fda871eb..d87244197d5c 100644
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -659,8 +659,6 @@ void __init setup_arch(char **cmdline_p)
 	ROOT_DEV = old_decode_dev(root_dev);
 #ifdef CONFIG_BLK_DEV_RAM
 	rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
-	rd_prompt = ((ram_flags & RAMDISK_PROMPT_FLAG) != 0);
-	rd_doload = ((ram_flags & RAMDISK_LOAD_FLAG) != 0);
 #endif
 
 	task_thread_info(&init_task)->kregs = &fake_swapper_regs;
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index a3767e74c758..b9a68d8e06d8 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -870,8 +870,6 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_BLK_DEV_RAM
 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
-	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
-	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
 #endif
 #ifdef CONFIG_EFI
 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index c9017e0584c0..eac184e6d657 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -25,6 +25,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/kthread.h>
+#include <linux/init_syscalls.h>
 #include <uapi/linux/mount.h>
 #include "base.h"
 
@@ -359,7 +360,7 @@ int __init devtmpfs_mount(void)
 	if (!thread)
 		return 0;
 
-	err = do_mount("devtmpfs", "dev", "devtmpfs", MS_SILENT, NULL);
+	err = init_mount("devtmpfs", "dev", "devtmpfs", MS_SILENT, NULL);
 	if (err)
 		printk(KERN_INFO "devtmpfs: error mounting %i\n", err);
 	else
@@ -378,30 +379,8 @@ static int handle(const char *name, umode_t mode, kuid_t uid, kgid_t gid,
 		return handle_remove(name, dev);
 }
 
-static int devtmpfs_setup(void *p)
+static void __noreturn devtmpfs_work_loop(void)
 {
-	int err;
-
-	err = ksys_unshare(CLONE_NEWNS);
-	if (err)
-		goto out;
-	err = do_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, NULL);
-	if (err)
-		goto out;
-	ksys_chdir("/.."); /* will traverse into overmounted root */
-	ksys_chroot(".");
-out:
-	*(int *)p = err;
-	complete(&setup_done);
-	return err;
-}
-
-static int devtmpfsd(void *p)
-{
-	int err = devtmpfs_setup(p);
-
-	if (err)
-		return err;
 	while (1) {
 		spin_lock(&req_lock);
 		while (requests) {
@@ -421,6 +400,38 @@ static int devtmpfsd(void *p)
 		spin_unlock(&req_lock);
 		schedule();
 	}
+}
+
+static int __init devtmpfs_setup(void *p)
+{
+	int err;
+
+	err = ksys_unshare(CLONE_NEWNS);
+	if (err)
+		goto out;
+	err = init_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, NULL);
+	if (err)
+		goto out;
+	init_chdir("/.."); /* will traverse into overmounted root */
+	init_chroot(".");
+out:
+	*(int *)p = err;
+	complete(&setup_done);
+	return err;
+}
+
+/*
+ * The __ref is because devtmpfs_setup needs to be __init for the routines it
+ * calls.  That call is done while devtmpfs_init, which is marked __init,
+ * synchronously waits for it to complete.
+ */
+static int __ref devtmpfsd(void *p)
+{
+	int err = devtmpfs_setup(p);
+
+	if (err)
+		return err;
+	devtmpfs_work_loop();
 	return 0;
 }
 
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 31840f95cd40..6d3e234dc46a 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -43,6 +43,9 @@ obj-$(CONFIG_MD_FAULTY)		+= faulty.o
 obj-$(CONFIG_MD_CLUSTER)	+= md-cluster.o
 obj-$(CONFIG_BCACHE)		+= bcache/
 obj-$(CONFIG_BLK_DEV_MD)	+= md-mod.o
+ifeq ($(CONFIG_BLK_DEV_MD),y)
+obj-y				+= md-autodetect.o
+endif
 obj-$(CONFIG_BLK_DEV_DM)	+= dm-mod.o
 obj-$(CONFIG_BLK_DEV_DM_BUILTIN) += dm-builtin.o
 obj-$(CONFIG_DM_UNSTRIPED)	+= dm-unstripe.o
diff --git a/init/do_mounts_md.c b/drivers/md/md-autodetect.c
index b84031528dd4..6bbec89976a7 100644
--- a/init/do_mounts_md.c
+++ b/drivers/md/md-autodetect.c
@@ -1,9 +1,15 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#include <linux/mount.h>
+#include <linux/major.h>
 #include <linux/delay.h>
+#include <linux/init_syscalls.h>
+#include <linux/raid/detect.h>
 #include <linux/raid/md_u.h>
 #include <linux/raid/md_p.h>
-
-#include "do_mounts.h"
+#include "md.h"
 
 /*
  * When md (and any require personalities) are compiled into the kernel
@@ -21,7 +27,7 @@ static int __initdata raid_noautodetect=1;
 #endif
 static int __initdata raid_autopart;
 
-static struct {
+static struct md_setup_args {
 	int minor;
 	int partitioned;
 	int level;
@@ -114,132 +120,118 @@ static int __init md_setup(char *str)
 	return 1;
 }
 
-static void __init md_setup_drive(void)
+static void __init md_setup_drive(struct md_setup_args *args)
 {
-	int minor, i, ent, partitioned;
-	dev_t dev;
-	dev_t devices[MD_SB_DISKS+1];
-
-	for (ent = 0; ent < md_setup_ents ; ent++) {
-		int fd;
-		int err = 0;
-		char *devname;
-		mdu_disk_info_t dinfo;
-		char name[16];
-
-		minor = md_setup_args[ent].minor;
-		partitioned = md_setup_args[ent].partitioned;
-		devname = md_setup_args[ent].device_names;
-
-		sprintf(name, "/dev/md%s%d", partitioned?"_d":"", minor);
-		if (partitioned)
-			dev = MKDEV(mdp_major, minor << MdpMinorShift);
-		else
-			dev = MKDEV(MD_MAJOR, minor);
-		create_dev(name, dev);
-		for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) {
-			char *p;
-			char comp_name[64];
-			u32 rdev;
-
-			p = strchr(devname, ',');
-			if (p)
-				*p++ = 0;
-
-			dev = name_to_dev_t(devname);
-			if (strncmp(devname, "/dev/", 5) == 0)
-				devname += 5;
-			snprintf(comp_name, 63, "/dev/%s", devname);
-			rdev = bstat(comp_name);
-			if (rdev)
-				dev = new_decode_dev(rdev);
-			if (!dev) {
-				printk(KERN_WARNING "md: Unknown device name: %s\n", devname);
-				break;
-			}
-
-			devices[i] = dev;
+	char *devname = args->device_names;
+	dev_t devices[MD_SB_DISKS + 1], mdev;
+	struct mdu_array_info_s ainfo = { };
+	struct block_device *bdev;
+	struct mddev *mddev;
+	int err = 0, i;
+	char name[16];
+
+	if (args->partitioned) {
+		mdev = MKDEV(mdp_major, args->minor << MdpMinorShift);
+		sprintf(name, "md_d%d", args->minor);
+	} else {
+		mdev = MKDEV(MD_MAJOR, args->minor);
+		sprintf(name, "md%d", args->minor);
+	}
 
-			devname = p;
+	for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) {
+		struct kstat stat;
+		char *p;
+		char comp_name[64];
+		dev_t dev;
+
+		p = strchr(devname, ',');
+		if (p)
+			*p++ = 0;
+
+		dev = name_to_dev_t(devname);
+		if (strncmp(devname, "/dev/", 5) == 0)
+			devname += 5;
+		snprintf(comp_name, 63, "/dev/%s", devname);
+		if (init_stat(comp_name, &stat, 0) == 0 && S_ISBLK(stat.mode))
+			dev = new_decode_dev(stat.rdev);
+		if (!dev) {
+			pr_warn("md: Unknown device name: %s\n", devname);
+			break;
 		}
-		devices[i] = 0;
 
-		if (!i)
-			continue;
+		devices[i] = dev;
+		devname = p;
+	}
+	devices[i] = 0;
 
-		printk(KERN_INFO "md: Loading md%s%d: %s\n",
-			partitioned ? "_d" : "", minor,
-			md_setup_args[ent].device_names);
+	if (!i)
+		return;
 
-		fd = ksys_open(name, 0, 0);
-		if (fd < 0) {
-			printk(KERN_ERR "md: open failed - cannot start "
-					"array %s\n", name);
-			continue;
-		}
-		if (ksys_ioctl(fd, SET_ARRAY_INFO, 0) == -EBUSY) {
-			printk(KERN_WARNING
-			       "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",
-			       minor);
-			ksys_close(fd);
-			continue;
-		}
+	pr_info("md: Loading %s: %s\n", name, args->device_names);
 
-		if (md_setup_args[ent].level != LEVEL_NONE) {
-			/* non-persistent */
-			mdu_array_info_t ainfo;
-			ainfo.level = md_setup_args[ent].level;
-			ainfo.size = 0;
-			ainfo.nr_disks =0;
-			ainfo.raid_disks =0;
-			while (devices[ainfo.raid_disks])
-				ainfo.raid_disks++;
-			ainfo.md_minor =minor;
-			ainfo.not_persistent = 1;
-
-			ainfo.state = (1 << MD_SB_CLEAN);
-			ainfo.layout = 0;
-			ainfo.chunk_size = md_setup_args[ent].chunk;
-			err = ksys_ioctl(fd, SET_ARRAY_INFO, (long)&ainfo);
-			for (i = 0; !err && i <= MD_SB_DISKS; i++) {
-				dev = devices[i];
-				if (!dev)
-					break;
-				dinfo.number = i;
-				dinfo.raid_disk = i;
-				dinfo.state = (1<<MD_DISK_ACTIVE)|(1<<MD_DISK_SYNC);
-				dinfo.major = MAJOR(dev);
-				dinfo.minor = MINOR(dev);
-				err = ksys_ioctl(fd, ADD_NEW_DISK,
-						 (long)&dinfo);
-			}
-		} else {
-			/* persistent */
-			for (i = 0; i <= MD_SB_DISKS; i++) {
-				dev = devices[i];
-				if (!dev)
-					break;
-				dinfo.major = MAJOR(dev);
-				dinfo.minor = MINOR(dev);
-				ksys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);
-			}
-		}
-		if (!err)
-			err = ksys_ioctl(fd, RUN_ARRAY, 0);
-		if (err)
-			printk(KERN_WARNING "md: starting md%d failed\n", minor);
-		else {
-			/* reread the partition table.
-			 * I (neilb) and not sure why this is needed, but I cannot
-			 * boot a kernel with devfs compiled in from partitioned md
-			 * array without it
-			 */
-			ksys_close(fd);
-			fd = ksys_open(name, 0, 0);
-			ksys_ioctl(fd, BLKRRPART, 0);
+	bdev = blkdev_get_by_dev(mdev, FMODE_READ, NULL);
+	if (IS_ERR(bdev)) {
+		pr_err("md: open failed - cannot start array %s\n", name);
+		return;
+	}
+
+	err = -EIO;
+	if (WARN(bdev->bd_disk->fops != &md_fops,
+			"Opening block device %x resulted in non-md device\n",
+			mdev))
+		goto out_blkdev_put;
+
+	mddev = bdev->bd_disk->private_data;
+
+	err = mddev_lock(mddev);
+	if (err) {
+		pr_err("md: failed to lock array %s\n", name);
+		goto out_blkdev_put;
+	}
+
+	if (!list_empty(&mddev->disks) || mddev->raid_disks) {
+		pr_warn("md: Ignoring %s, already autodetected. (Use raid=noautodetect)\n",
+		       name);
+		goto out_unlock;
+	}
+
+	if (args->level != LEVEL_NONE) {
+		/* non-persistent */
+		ainfo.level = args->level;
+		ainfo.md_minor = args->minor;
+		ainfo.not_persistent = 1;
+		ainfo.state = (1 << MD_SB_CLEAN);
+		ainfo.chunk_size = args->chunk;
+		while (devices[ainfo.raid_disks])
+			ainfo.raid_disks++;
+	}
+
+	err = md_set_array_info(mddev, &ainfo);
+
+	for (i = 0; i <= MD_SB_DISKS && devices[i]; i++) {
+		struct mdu_disk_info_s dinfo = {
+			.major	= MAJOR(devices[i]),
+			.minor	= MINOR(devices[i]),
+		};
+
+		if (args->level != LEVEL_NONE) {
+			dinfo.number = i;
+			dinfo.raid_disk = i;
+			dinfo.state =
+				(1 << MD_DISK_ACTIVE) | (1 << MD_DISK_SYNC);
 		}
-		ksys_close(fd);
+
+		md_add_new_disk(mddev, &dinfo);
 	}
+
+	if (!err)
+		err = do_md_run(mddev);
+	if (err)
+		pr_warn("md: starting %s failed\n", name);
+out_unlock:
+	mddev_unlock(mddev);
+out_blkdev_put:
+	blkdev_put(bdev, FMODE_READ);
 }
 
 static int __init raid_setup(char *str)
@@ -274,8 +266,6 @@ __setup("md=", md_setup);
 
 static void __init autodetect_raid(void)
 {
-	int fd;
-
 	/*
 	 * Since we don't want to detect and use half a raid array, we need to
 	 * wait for the known devices to complete their probing
@@ -284,21 +274,18 @@ static void __init autodetect_raid(void)
 	printk(KERN_INFO "md: If you don't use raid, use raid=noautodetect\n");
 
 	wait_for_device_probe();
-
-	fd = ksys_open("/dev/md0", 0, 0);
-	if (fd >= 0) {
-		ksys_ioctl(fd, RAID_AUTORUN, raid_autopart);
-		ksys_close(fd);
-	}
+	md_autostart_arrays(raid_autopart);
 }
 
 void __init md_run_setup(void)
 {
-	create_dev("/dev/md0", MKDEV(MD_MAJOR, 0));
+	int ent;
 
 	if (raid_noautodetect)
 		printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=autodetect will force)\n");
 	else
 		autodetect_raid();
-	md_setup_drive();
+
+	for (ent = 0; ent < md_setup_ents; ent++)
+		md_setup_drive(&md_setup_args[ent]);
 }
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 153bc766bc5a..15bbdc1630ed 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -68,10 +68,6 @@
 #include "md-bitmap.h"
 #include "md-cluster.h"
 
-#ifndef MODULE
-static void autostart_arrays(int part);
-#endif
-
 /* pers_list is a list of registered personalities protected
  * by pers_lock.
  * pers_lock does extra service to protect accesses to
@@ -332,8 +328,6 @@ static struct ctl_table raid_root_table[] = {
 	{  }
 };
 
-static const struct block_device_operations md_fops;
-
 static int start_readonly;
 
 /*
@@ -4426,7 +4420,6 @@ array_state_show(struct mddev *mddev, char *page)
 
 static int do_md_stop(struct mddev *mddev, int ro, struct block_device *bdev);
 static int md_set_readonly(struct mddev *mddev, struct block_device *bdev);
-static int do_md_run(struct mddev *mddev);
 static int restart_array(struct mddev *mddev);
 
 static ssize_t
@@ -6089,7 +6082,7 @@ abort:
 }
 EXPORT_SYMBOL_GPL(md_run);
 
-static int do_md_run(struct mddev *mddev)
+int do_md_run(struct mddev *mddev)
 {
 	int err;
 
@@ -6724,7 +6717,7 @@ static int get_disk_info(struct mddev *mddev, void __user * arg)
 	return 0;
 }
 
-static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info)
+int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info)
 {
 	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
 	struct md_rdev *rdev;
@@ -6770,7 +6763,7 @@ static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info)
 	}
 
 	/*
-	 * add_new_disk can be used once the array is assembled
+	 * md_add_new_disk can be used once the array is assembled
 	 * to add "hot spares".  They must already have a superblock
 	 * written
 	 */
@@ -6883,7 +6876,7 @@ static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info)
 		return err;
 	}
 
-	/* otherwise, add_new_disk is only allowed
+	/* otherwise, md_add_new_disk is only allowed
 	 * for major_version==0 superblocks
 	 */
 	if (mddev->major_version != 0) {
@@ -7128,7 +7121,7 @@ static int set_bitmap_file(struct mddev *mddev, int fd)
 }
 
 /*
- * set_array_info is used two different ways
+ * md_set_array_info is used two different ways
  * The original usage is when creating a new array.
  * In this usage, raid_disks is > 0 and it together with
  *  level, size, not_persistent,layout,chunksize determine the
@@ -7140,9 +7133,8 @@ static int set_bitmap_file(struct mddev *mddev, int fd)
  *  The minor and patch _version numbers are also kept incase the
  *  super_block handler wishes to interpret them.
  */
-static int set_array_info(struct mddev *mddev, mdu_array_info_t *info)
+int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info)
 {
-
 	if (info->raid_disks == 0) {
 		/* just setting version number for superblock loading */
 		if (info->major_version < 0 ||
@@ -7492,7 +7484,6 @@ static inline bool md_ioctl_valid(unsigned int cmd)
 	case GET_DISK_INFO:
 	case HOT_ADD_DISK:
 	case HOT_REMOVE_DISK:
-	case RAID_AUTORUN:
 	case RAID_VERSION:
 	case RESTART_ARRAY_RW:
 	case RUN_ARRAY:
@@ -7538,13 +7529,6 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 	case RAID_VERSION:
 		err = get_version(argp);
 		goto out;
-
-#ifndef MODULE
-	case RAID_AUTORUN:
-		err = 0;
-		autostart_arrays(arg);
-		goto out;
-#endif
 	default:;
 	}
 
@@ -7643,7 +7627,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 			err = -EBUSY;
 			goto unlock;
 		}
-		err = set_array_info(mddev, &info);
+		err = md_set_array_info(mddev, &info);
 		if (err) {
 			pr_warn("md: couldn't set array info. %d\n", err);
 			goto unlock;
@@ -7697,7 +7681,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 				/* Need to clear read-only for this */
 				break;
 			else
-				err = add_new_disk(mddev, &info);
+				err = md_add_new_disk(mddev, &info);
 			goto unlock;
 		}
 		break;
@@ -7765,7 +7749,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 		if (copy_from_user(&info, argp, sizeof(info)))
 			err = -EFAULT;
 		else
-			err = add_new_disk(mddev, &info);
+			err = md_add_new_disk(mddev, &info);
 		goto unlock;
 	}
 
@@ -7888,7 +7872,7 @@ static unsigned int md_check_events(struct gendisk *disk, unsigned int clearing)
 	return ret;
 }
 
-static const struct block_device_operations md_fops =
+const struct block_device_operations md_fops =
 {
 	.owner		= THIS_MODULE,
 	.submit_bio	= md_submit_bio,
@@ -9791,7 +9775,7 @@ void md_autodetect_dev(dev_t dev)
 	}
 }
 
-static void autostart_arrays(int part)
+void md_autostart_arrays(int part)
 {
 	struct md_rdev *rdev;
 	struct detected_devices_node *node_detected_dev;
diff --git a/drivers/md/md.h b/drivers/md/md.h
index f79b5b4101ef..d9c4e6b7e939 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -803,4 +803,16 @@ static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio
 	    !bio->bi_disk->queue->limits.max_write_zeroes_sectors)
 		mddev->queue->limits.max_write_zeroes_sectors = 0;
 }
+
+struct mdu_array_info_s;
+struct mdu_disk_info_s;
+
+extern int mdp_major;
+void md_autostart_arrays(int part);
+int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
+int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
+int do_md_run(struct mddev *mddev);
+
+extern const struct block_device_operations md_fops;
+
 #endif /* _MD_MD_H */
diff --git a/fs/Makefile b/fs/Makefile
index 2ce5112b02c8..1c7b0e3f6daa 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -13,7 +13,7 @@ obj-y :=	open.o read_write.o file_table.o super.o \
 		seq_file.o xattr.o libfs.o fs-writeback.o \
 		pnode.o splice.o sync.o utimes.o d_path.o \
 		stack.o fs_struct.o statfs.o fs_pin.o nsfs.o \
-		fs_types.o fs_context.o fs_parser.o fsopen.o
+		fs_types.o fs_context.o fs_parser.o fsopen.o init.o
 
 ifeq ($(CONFIG_BLOCK),y)
 obj-y +=	buffer.o block_dev.o direct-io.o mpage.o
diff --git a/fs/file.c b/fs/file.c
index 4cb9ef4d8571..21c0893f2f1d 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -1145,7 +1145,7 @@ SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd)
 	return ksys_dup3(oldfd, newfd, 0);
 }
 
-int ksys_dup(unsigned int fildes)
+SYSCALL_DEFINE1(dup, unsigned int, fildes)
 {
 	int ret = -EBADF;
 	struct file *file = fget_raw(fildes);
@@ -1160,11 +1160,6 @@ int ksys_dup(unsigned int fildes)
 	return ret;
 }
 
-SYSCALL_DEFINE1(dup, unsigned int, fildes)
-{
-	return ksys_dup(fildes);
-}
-
 int f_dupfd(unsigned int from, struct file *file, unsigned flags)
 {
 	int err;
diff --git a/fs/init.c b/fs/init.c
new file mode 100644
index 000000000000..e9c320a48cf1
--- /dev/null
+++ b/fs/init.c
@@ -0,0 +1,265 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Routines that mimic syscalls, but don't use the user address space or file
+ * descriptors.  Only for init/ and related early init code.
+ */
+#include <linux/init.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/fs.h>
+#include <linux/fs_struct.h>
+#include <linux/file.h>
+#include <linux/init_syscalls.h>
+#include <linux/security.h>
+#include "internal.h"
+
+int __init init_mount(const char *dev_name, const char *dir_name,
+		const char *type_page, unsigned long flags, void *data_page)
+{
+	struct path path;
+	int ret;
+
+	ret = kern_path(dir_name, LOOKUP_FOLLOW, &path);
+	if (ret)
+		return ret;
+	ret = path_mount(dev_name, &path, type_page, flags, data_page);
+	path_put(&path);
+	return ret;
+}
+
+int __init init_umount(const char *name, int flags)
+{
+	int lookup_flags = LOOKUP_MOUNTPOINT;
+	struct path path;
+	int ret;
+
+	if (!(flags & UMOUNT_NOFOLLOW))
+		lookup_flags |= LOOKUP_FOLLOW;
+	ret = kern_path(name, lookup_flags, &path);
+	if (ret)
+		return ret;
+	return path_umount(&path, flags);
+}
+
+int __init init_chdir(const char *filename)
+{
+	struct path path;
+	int error;
+
+	error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+	if (error)
+		return error;
+	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	if (!error)
+		set_fs_pwd(current->fs, &path);
+	path_put(&path);
+	return error;
+}
+
+int __init init_chroot(const char *filename)
+{
+	struct path path;
+	int error;
+
+	error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+	if (error)
+		return error;
+	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	if (error)
+		goto dput_and_out;
+	error = -EPERM;
+	if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
+		goto dput_and_out;
+	error = security_path_chroot(&path);
+	if (error)
+		goto dput_and_out;
+	set_fs_root(current->fs, &path);
+dput_and_out:
+	path_put(&path);
+	return error;
+}
+
+int __init init_chown(const char *filename, uid_t user, gid_t group, int flags)
+{
+	int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
+	struct path path;
+	int error;
+
+	error = kern_path(filename, lookup_flags, &path);
+	if (error)
+		return error;
+	error = mnt_want_write(path.mnt);
+	if (!error) {
+		error = chown_common(&path, user, group);
+		mnt_drop_write(path.mnt);
+	}
+	path_put(&path);
+	return error;
+}
+
+int __init init_chmod(const char *filename, umode_t mode)
+{
+	struct path path;
+	int error;
+
+	error = kern_path(filename, LOOKUP_FOLLOW, &path);
+	if (error)
+		return error;
+	error = chmod_common(&path, mode);
+	path_put(&path);
+	return error;
+}
+
+int __init init_eaccess(const char *filename)
+{
+	struct path path;
+	int error;
+
+	error = kern_path(filename, LOOKUP_FOLLOW, &path);
+	if (error)
+		return error;
+	error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
+	path_put(&path);
+	return error;
+}
+
+int __init init_stat(const char *filename, struct kstat *stat, int flags)
+{
+	int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
+	struct path path;
+	int error;
+
+	error = kern_path(filename, lookup_flags, &path);
+	if (error)
+		return error;
+	error = vfs_getattr(&path, stat, STATX_BASIC_STATS,
+			    flags | AT_NO_AUTOMOUNT);