Revert "CHROMIUM: dm: boot time specification of dm="

This reverts commit 0cc78aab2839588831e7b148596fa7a931f6e256.

Bug: 129143048
Test: Boot cuttlefish from AOSP

Signed-off-by: Sandeep Patil <sspatil@android.com>

Documentation/admin-guide/kernel-parameters.txt

@@ -837,9 +837,6 @@
 
 	dis_ucode_ldr	[X86] Disable the microcode loader.
 
-	dm=		[DM] Allows early creation of a device-mapper device.
-			See Documentation/device-mapper/boot.txt.
-
 	dma_debug=off	If the kernel is compiled with DMA_API_DEBUG support,
 			this option disables the debugging code at boot.
 

Documentation/device-mapper/boot.txt

@@ -1,42 +0,0 @@
-Boot time creation of mapped devices
-===================================
-
-It is possible to configure a device mapper device to act as the root
-device for your system in two ways.
-
-The first is to build an initial ramdisk which boots to a minimal
-userspace which configures the device, then pivot_root(8) in to it.
-
-For simple device mapper configurations, it is possible to boot directly
-using the following kernel command line:
-
-dm="<name> <uuid> <ro>,table line 1,...,table line n"
-
-name = the name to associate with the device
-	after boot, udev, if used, will use that name to label
-	the device node.
-uuid = may be 'none' or the UUID desired for the device.
-ro = may be "ro" or "rw".  If "ro", the device and device table will be
-	marked read-only.
-
-Each table line may be as normal when using the dmsetup tool except for
-two variations:
-1. Any use of commas will be interpreted as a newline
-2. Quotation marks cannot be escaped and cannot be used without
-   terminating the dm= argument.
-
-Unless renamed by udev, the device node created will be dm-0 as the
-first minor number for the device-mapper is used during early creation.
-
-Example
-=======
-
-- Booting to a linear array made up of user-mode linux block devices:
-
-  dm="lroot none 0, 0 4096 linear 98:16 0, 4096 4096 linear 98:32 0" \
-  root=/dev/dm-0
-
-Will boot to a rw dm-linear target of 8192 sectors split across two
-block devices identified by their major:minor numbers.  After boot, udev
-will rename this target to /dev/mapper/lroot (depending on the rules).
-No uuid was assigned.

drivers/md/dm-ioctl.c

@@ -1986,45 +1986,6 @@ void dm_interface_exit(void)
 	dm_hash_exit();
 }
 
-
-/**
- * dm_ioctl_export - Permanently export a mapped device via the ioctl interface
- * @md: Pointer to mapped_device
- * @name: Buffer (size DM_NAME_LEN) for name
- * @uuid: Buffer (size DM_UUID_LEN) for uuid or NULL if not desired
- */
-int dm_ioctl_export(struct mapped_device *md, const char *name,
-		    const char *uuid)
-{
-	int r = 0;
-	struct hash_cell *hc;
-
-	if (!md) {
-		r = -ENXIO;
-		goto out;
-	}
-
-	/* The name and uuid can only be set once. */
-	mutex_lock(&dm_hash_cells_mutex);
-	hc = dm_get_mdptr(md);
-	mutex_unlock(&dm_hash_cells_mutex);
-	if (hc) {
-		DMERR("%s: already exported", dm_device_name(md));
-		r = -ENXIO;
-		goto out;
-	}
-
-	r = dm_hash_insert(name, uuid, md);
-	if (r) {
-		DMERR("%s: could not bind to '%s'", dm_device_name(md), name);
-		goto out;
-	}
-
-	/* Let udev know we've changed. */
-	dm_kobject_uevent(md, KOBJ_CHANGE, dm_get_event_nr(md));
-out:
-	return r;
-}
 /**
  * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
  * @md: Pointer to mapped_device

drivers/md/dm-table.c

@@ -11,7 +11,6 @@
 #include <linux/vmalloc.h>
 #include <linux/blkdev.h>
 #include <linux/namei.h>
-#include <linux/mount.h>
 #include <linux/ctype.h>
 #include <linux/string.h>
 #include <linux/slab.h>

include/linux/device-mapper.h

@@ -430,12 +430,6 @@ void dm_put(struct mapped_device *md);
 void dm_set_mdptr(struct mapped_device *md, void *ptr);
 void *dm_get_mdptr(struct mapped_device *md);
 
-/*
- * Export the device via the ioctl interface (uses mdptr).
- */
-int dm_ioctl_export(struct mapped_device *md, const char *name,
-		    const char *uuid);
-
 /*
  * A device can still be used while suspended, but I/O is deferred.
  */

init/Makefile

@@ -18,7 +18,6 @@ mounts-y			:= do_mounts.o
 mounts-$(CONFIG_BLK_DEV_RAM)	+= do_mounts_rd.o
 mounts-$(CONFIG_BLK_DEV_INITRD)	+= do_mounts_initrd.o
 mounts-$(CONFIG_BLK_DEV_MD)	+= do_mounts_md.o
-mounts-$(CONFIG_BLK_DEV_DM)	+= do_mounts_dm.o
 
 # dependencies on generated files need to be listed explicitly
 $(obj)/version.o: include/generated/compile.h

init/do_mounts.c

@@ -565,7 +565,6 @@ void __init prepare_namespace(void)
 	wait_for_device_probe();
 
 	md_run_setup();
-	dm_run_setup();
 
 	if (saved_root_name[0]) {
 		root_device_name = saved_root_name;

init/do_mounts.h

@@ -61,13 +61,3 @@ void md_run_setup(void);
 static inline void md_run_setup(void) {}
 
 #endif
-
-#ifdef CONFIG_BLK_DEV_DM
-
-void dm_run_setup(void);
-
-#else
-
-static inline void dm_run_setup(void) {}
-
-#endif