diff --git a/include/linux/raid/linear.h b/include/linux/raid/linear.h
new file mode 100644
index 0000000..e04c4fe
--- /dev/null
+++ b/include/linux/raid/linear.h
@@ -0,0 +1,27 @@
+#ifndef _LINEAR_H
+#define _LINEAR_H
+
+#include <linux/raid/md.h>
+
+struct dev_info {
+	mdk_rdev_t	*rdev;
+	sector_t	size;
+	sector_t	offset;
+};
+
+typedef struct dev_info dev_info_t;
+
+struct linear_private_data
+{
+	dev_info_t		**hash_table;
+	dev_info_t		*smallest;
+	int			nr_zones;
+	dev_info_t		disks[0];
+};
+
+
+typedef struct linear_private_data linear_conf_t;
+
+#define mddev_to_conf(mddev) ((linear_conf_t *) mddev->private)
+
+#endif
diff --git a/include/linux/raid/md.h b/include/linux/raid/md.h
new file mode 100644
index 0000000..a6a67d1
--- /dev/null
+++ b/include/linux/raid/md.h
@@ -0,0 +1,84 @@
+/*
+   md.h : Multiple Devices driver for Linux
+          Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
+          Copyright (C) 1994-96 Marc ZYNGIER
+	  <zyngier@ufr-info-p7.ibp.fr> or
+	  <maz@gloups.fdn.fr>
+	  
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+   
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+*/
+
+#ifndef _MD_H
+#define _MD_H
+
+#include <linux/blkdev.h>
+#include <asm/semaphore.h>
+#include <linux/major.h>
+#include <linux/ioctl.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/hdreg.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/smp_lock.h>
+#include <linux/delay.h>
+#include <net/checksum.h>
+#include <linux/random.h>
+#include <linux/kernel_stat.h>
+#include <asm/io.h>
+#include <linux/completion.h>
+#include <linux/mempool.h>
+#include <linux/list.h>
+#include <linux/reboot.h>
+#include <linux/vmalloc.h>
+#include <linux/blkpg.h>
+#include <linux/bio.h>
+
+/*
+ * 'md_p.h' holds the 'physical' layout of RAID devices
+ * 'md_u.h' holds the user <=> kernel API
+ *
+ * 'md_k.h' holds kernel internal definitions
+ */
+
+#include <linux/raid/md_p.h>
+#include <linux/raid/md_u.h>
+#include <linux/raid/md_k.h>
+
+/*
+ * Different major versions are not compatible.
+ * Different minor versions are only downward compatible.
+ * Different patchlevel versions are downward and upward compatible.
+ */
+#define MD_MAJOR_VERSION                0
+#define MD_MINOR_VERSION                90
+#define MD_PATCHLEVEL_VERSION           1
+
+extern int register_md_personality (int p_num, mdk_personality_t *p);
+extern int unregister_md_personality (int p_num);
+extern mdk_thread_t * md_register_thread (void (*run) (mddev_t *mddev),
+				mddev_t *mddev, const char *name);
+extern void md_unregister_thread (mdk_thread_t *thread);
+extern void md_wakeup_thread(mdk_thread_t *thread);
+extern void md_check_recovery(mddev_t *mddev);
+extern void md_write_start(mddev_t *mddev);
+extern void md_write_end(mddev_t *mddev);
+extern void md_handle_safemode(mddev_t *mddev);
+extern void md_done_sync(mddev_t *mddev, int blocks, int ok);
+extern void md_error (mddev_t *mddev, mdk_rdev_t *rdev);
+extern void md_unplug_mddev(mddev_t *mddev);
+
+extern void md_print_devices (void);
+
+#define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); }
+
+#endif 
+
diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h
new file mode 100644
index 0000000..c9a0d40
--- /dev/null
+++ b/include/linux/raid/md_k.h
@@ -0,0 +1,369 @@
+/*
+   md_k.h : kernel internal structure of the Linux MD driver
+          Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
+	  
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+   
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+*/
+
+#ifndef _MD_K_H
+#define _MD_K_H
+
+#define MD_RESERVED       0UL
+#define LINEAR            1UL
+#define RAID0             2UL
+#define RAID1             3UL
+#define RAID5             4UL
+#define TRANSLUCENT       5UL
+#define HSM               6UL
+#define MULTIPATH         7UL
+#define RAID6		  8UL
+#define	RAID10		  9UL
+#define FAULTY		  10UL
+#define MAX_PERSONALITY   11UL
+
+#define	LEVEL_MULTIPATH		(-4)
+#define	LEVEL_LINEAR		(-1)
+#define	LEVEL_FAULTY		(-5)
+
+#define MaxSector (~(sector_t)0)
+#define MD_THREAD_NAME_MAX 14
+
+static inline int pers_to_level (int pers)
+{
+	switch (pers) {
+		case FAULTY:		return LEVEL_FAULTY;
+		case MULTIPATH:		return LEVEL_MULTIPATH;
+		case HSM:		return -3;
+		case TRANSLUCENT:	return -2;
+		case LINEAR:		return LEVEL_LINEAR;
+		case RAID0:		return 0;
+		case RAID1:		return 1;
+		case RAID5:		return 5;
+		case RAID6:		return 6;
+		case RAID10:		return 10;
+	}
+	BUG();
+	return MD_RESERVED;
+}
+
+static inline int level_to_pers (int level)
+{
+	switch (level) {
+		case LEVEL_FAULTY: return FAULTY;
+		case LEVEL_MULTIPATH: return MULTIPATH;
+		case -3: return HSM;
+		case -2: return TRANSLUCENT;
+		case LEVEL_LINEAR: return LINEAR;
+		case 0: return RAID0;
+		case 1: return RAID1;
+		case 4:
+		case 5: return RAID5;
+		case 6: return RAID6;
+		case 10: return RAID10;
+	}
+	return MD_RESERVED;
+}
+
+typedef struct mddev_s mddev_t;
+typedef struct mdk_rdev_s mdk_rdev_t;
+
+#define MAX_MD_DEVS  256	/* Max number of md dev */
+
+/*
+ * options passed in raidrun:
+ */
+
+#define MAX_CHUNK_SIZE (4096*1024)
+
+/*
+ * default readahead
+ */
+
+static inline int disk_faulty(mdp_disk_t * d)
+{
+	return d->state & (1 << MD_DISK_FAULTY);
+}
+
+static inline int disk_active(mdp_disk_t * d)
+{
+	return d->state & (1 << MD_DISK_ACTIVE);
+}
+
+static inline int disk_sync(mdp_disk_t * d)
+{
+	return d->state & (1 << MD_DISK_SYNC);
+}
+
+static inline int disk_spare(mdp_disk_t * d)
+{
+	return !disk_sync(d) && !disk_active(d) && !disk_faulty(d);
+}
+
+static inline int disk_removed(mdp_disk_t * d)
+{
+	return d->state & (1 << MD_DISK_REMOVED);
+}
+
+static inline void mark_disk_faulty(mdp_disk_t * d)
+{
+	d->state |= (1 << MD_DISK_FAULTY);
+}
+
+static inline void mark_disk_active(mdp_disk_t * d)
+{
+	d->state |= (1 << MD_DISK_ACTIVE);
+}
+
+static inline void mark_disk_sync(mdp_disk_t * d)
+{
+	d->state |= (1 << MD_DISK_SYNC);
+}
+
+static inline void mark_disk_spare(mdp_disk_t * d)
+{
+	d->state = 0;
+}
+
+static inline void mark_disk_removed(mdp_disk_t * d)
+{
+	d->state = (1 << MD_DISK_FAULTY) | (1 << MD_DISK_REMOVED);
+}
+
+static inline void mark_disk_inactive(mdp_disk_t * d)
+{
+	d->state &= ~(1 << MD_DISK_ACTIVE);
+}
+
+static inline void mark_disk_nonsync(mdp_disk_t * d)
+{
+	d->state &= ~(1 << MD_DISK_SYNC);
+}
+
+/*
+ * MD's 'extended' device
+ */
+struct mdk_rdev_s
+{
+	struct list_head same_set;	/* RAID devices within the same set */
+
+	sector_t size;			/* Device size (in blocks) */
+	mddev_t *mddev;			/* RAID array if running */
+	unsigned long last_events;	/* IO event timestamp */
+
+	struct block_device *bdev;	/* block device handle */
+
+	struct page	*sb_page;
+	int		sb_loaded;
+	sector_t	data_offset;	/* start of data in array */
+	sector_t	sb_offset;
+	int		preferred_minor;	/* autorun support */
+
+	/* A device can be in one of three states based on two flags:
+	 * Not working:   faulty==1 in_sync==0
+	 * Fully working: faulty==0 in_sync==1
+	 * Working, but not
+	 * in sync with array
+	 *                faulty==0 in_sync==0
+	 *
+	 * It can never have faulty==1, in_sync==1
+	 * This reduces the burden of testing multiple flags in many cases
+	 */
+	int faulty;			/* if faulty do not issue IO requests */
+	int in_sync;			/* device is a full member of the array */
+
+	int desc_nr;			/* descriptor index in the superblock */
+	int raid_disk;			/* role of device in array */
+
+	atomic_t	nr_pending;	/* number of pending requests.
+					 * only maintained for arrays that
+					 * support hot removal
+					 */
+};
+
+typedef struct mdk_personality_s mdk_personality_t;
+
+struct mddev_s
+{
+	void				*private;
+	mdk_personality_t		*pers;
+	dev_t				unit;
+	int				md_minor;
+	struct list_head 		disks;
+	int				sb_dirty;
+	int				ro;
+
+	struct gendisk			*gendisk;
+
+	/* Superblock information */
+	int				major_version,
+					minor_version,
+					patch_version;
+	int				persistent;
+	int				chunk_size;
+	time_t				ctime, utime;
+	int				level, layout;
+	int				raid_disks;
+	int				max_disks;
+	sector_t			size; /* used size of component devices */
+	sector_t			array_size; /* exported array size */
+	__u64				events;
+
+	char				uuid[16];
+
+	struct mdk_thread_s		*thread;	/* management thread */
+	struct mdk_thread_s		*sync_thread;	/* doing resync or reconstruct */
+	sector_t			curr_resync;	/* blocks scheduled */
+	unsigned long			resync_mark;	/* a recent timestamp */
+	sector_t			resync_mark_cnt;/* blocks written at resync_mark */
+
+	sector_t			resync_max_sectors; /* may be set by personality */
+	/* recovery/resync flags 
+	 * NEEDED:   we might need to start a resync/recover
+	 * RUNNING:  a thread is running, or about to be started
+	 * SYNC:     actually doing a resync, not a recovery
+	 * ERR:      and IO error was detected - abort the resync/recovery
+	 * INTR:     someone requested a (clean) early abort.
+	 * DONE:     thread is done and is waiting to be reaped
+	 */
+#define	MD_RECOVERY_RUNNING	0
+#define	MD_RECOVERY_SYNC	1
+#define	MD_RECOVERY_ERR		2
+#define	MD_RECOVERY_INTR	3
+#define	MD_RECOVERY_DONE	4
+#define	MD_RECOVERY_NEEDED	5
+	unsigned long			recovery;
+
+	int				in_sync;	/* know to not need resync */
+	struct semaphore		reconfig_sem;
+	atomic_t			active;
+
+	int				changed;	/* true if we might need to reread partition info */
+	int				degraded;	/* whether md should consider
+							 * adding a spare
+							 */
+
+	atomic_t			recovery_active; /* blocks scheduled, but not written */
+	wait_queue_head_t		recovery_wait;
+	sector_t			recovery_cp;
+	unsigned int			safemode;	/* if set, update "clean" superblock
+							 * when no writes pending.
+							 */ 
+	unsigned int			safemode_delay;
+	struct timer_list		safemode_timer;
+	atomic_t			writes_pending; 
+	request_queue_t			*queue;	/* for plugging ... */
+
+	struct list_head		all_mddevs;
+};
+
+
+static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev)
+{
+	int faulty = rdev->faulty;
+	if (atomic_dec_and_test(&rdev->nr_pending) && faulty)
+		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+}
+
+static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
+{
+        atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
+}
+
+struct mdk_personality_s
+{
+	char *name;
+	struct module *owner;
+	int (*make_request)(request_queue_t *q, struct bio *bio);
+	int (*run)(mddev_t *mddev);
+	int (*stop)(mddev_t *mddev);
+	void (*status)(struct seq_file *seq, mddev_t *mddev);
+	/* error_handler must set ->faulty and clear ->in_sync
+	 * if appropriate, and should abort recovery if needed 
+	 */
+	void (*error_handler)(mddev_t *mddev, mdk_rdev_t *rdev);
+	int (*hot_add_disk) (mddev_t *mddev, mdk_rdev_t *rdev);
+	int (*hot_remove_disk) (mddev_t *mddev, int number);
+	int (*spare_active) (mddev_t *mddev);
+	int (*sync_request)(mddev_t *mddev, sector_t sector_nr, int go_faster);
+	int (*resize) (mddev_t *mddev, sector_t sectors);
+	int (*reshape) (mddev_t *mddev, int raid_disks);
+	int (*reconfig) (mddev_t *mddev, int layout, int chunk_size);
+};
+
+
+static inline char * mdname (mddev_t * mddev)
+{
+	return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
+}
+
+extern mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr);
+
+/*
+ * iterates through some rdev ringlist. It's safe to remove the
+ * current 'rdev'. Dont touch 'tmp' though.
+ */
+#define ITERATE_RDEV_GENERIC(head,rdev,tmp)				\
+									\
+	for ((tmp) = (head).next;					\
+		(rdev) = (list_entry((tmp), mdk_rdev_t, same_set)),	\
+			(tmp) = (tmp)->next, (tmp)->prev != &(head)	\
+		; )
+/*
+ * iterates through the 'same array disks' ringlist
+ */
+#define ITERATE_RDEV(mddev,rdev,tmp)					\
+	ITERATE_RDEV_GENERIC((mddev)->disks,rdev,tmp)
+
+/*
+ * Iterates through 'pending RAID disks'
+ */
+#define ITERATE_RDEV_PENDING(rdev,tmp)					\
+	ITERATE_RDEV_GENERIC(pending_raid_disks,rdev,tmp)
+
+typedef struct mdk_thread_s {
+	void			(*run) (mddev_t *mddev);
+	mddev_t			*mddev;
+	wait_queue_head_t	wqueue;
+	unsigned long           flags;
+	struct completion	*event;
+	struct task_struct	*tsk;
+	const char		*name;
+} mdk_thread_t;
+
+#define THREAD_WAKEUP  0
+
+#define __wait_event_lock_irq(wq, condition, lock, cmd) 		\
+do {									\
+	wait_queue_t __wait;						\
+	init_waitqueue_entry(&__wait, current);				\
+									\
+	add_wait_queue(&wq, &__wait);					\
+	for (;;) {							\
+		set_current_state(TASK_UNINTERRUPTIBLE);		\
+		if (condition)						\
+			break;						\
+		spin_unlock_irq(&lock);					\
+		cmd;							\
+		schedule();						\
+		spin_lock_irq(&lock);					\
+	}								\
+	current->state = TASK_RUNNING;					\
+	remove_wait_queue(&wq, &__wait);				\
+} while (0)
+
+#define wait_event_lock_irq(wq, condition, lock, cmd) 			\
+do {									\
+	if (condition)	 						\
+		break;							\
+	__wait_event_lock_irq(wq, condition, lock, cmd);		\
+} while (0)
+
+#endif
+
diff --git a/include/linux/raid/md_p.h b/include/linux/raid/md_p.h
new file mode 100644
index 0000000..8ba95d6
--- /dev/null
+++ b/include/linux/raid/md_p.h
@@ -0,0 +1,230 @@
+/*
+   md_p.h : physical layout of Linux RAID devices
+          Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman
+	  
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+   
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+*/
+
+#ifndef _MD_P_H
+#define _MD_P_H
+
+/*
+ * RAID superblock.
+ *
+ * The RAID superblock maintains some statistics on each RAID configuration.
+ * Each real device in the RAID set contains it near the end of the device.
+ * Some of the ideas are copied from the ext2fs implementation.
+ *
+ * We currently use 4096 bytes as follows:
+ *
+ *	word offset	function
+ *
+ *	   0  -    31	Constant generic RAID device information.
+ *        32  -    63   Generic state information.
+ *	  64  -   127	Personality specific information.
+ *	 128  -   511	12 32-words descriptors of the disks in the raid set.
+ *	 512  -   911	Reserved.
+ *	 912  -  1023	Disk specific descriptor.
+ */
+
+/*
+ * If x is the real device size in bytes, we return an apparent size of:
+ *
+ *	y = (x & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES
+ *
+ * and place the 4kB superblock at offset y.
+ */
+#define MD_RESERVED_BYTES		(64 * 1024)
+#define MD_RESERVED_SECTORS		(MD_RESERVED_BYTES / 512)
+#define MD_RESERVED_BLOCKS		(MD_RESERVED_BYTES / BLOCK_SIZE)
+
+#define MD_NEW_SIZE_SECTORS(x)		((x & ~(MD_RESERVED_SECTORS - 1)) - MD_RESERVED_SECTORS)
+#define MD_NEW_SIZE_BLOCKS(x)		((x & ~(MD_RESERVED_BLOCKS - 1)) - MD_RESERVED_BLOCKS)
+
+#define MD_SB_BYTES			4096
+#define MD_SB_WORDS			(MD_SB_BYTES / 4)
+#define MD_SB_BLOCKS			(MD_SB_BYTES / BLOCK_SIZE)
+#define MD_SB_SECTORS			(MD_SB_BYTES / 512)
+
+/*
+ * The following are counted in 32-bit words
+ */
+#define	MD_SB_GENERIC_OFFSET		0
+#define MD_SB_PERSONALITY_OFFSET	64
+#define MD_SB_DISKS_OFFSET		128
+#define MD_SB_DESCRIPTOR_OFFSET		992
+
+#define MD_SB_GENERIC_CONSTANT_WORDS	32
+#define MD_SB_GENERIC_STATE_WORDS	32
+#define MD_SB_GENERIC_WORDS		(MD_SB_GENERIC_CONSTANT_WORDS + MD_SB_GENERIC_STATE_WORDS)
+#define MD_SB_PERSONALITY_WORDS		64
+#define MD_SB_DESCRIPTOR_WORDS		32
+#define MD_SB_DISKS			27
+#define MD_SB_DISKS_WORDS		(MD_SB_DISKS*MD_SB_DESCRIPTOR_WORDS)
+#define MD_SB_RESERVED_WORDS		(1024 - MD_SB_GENERIC_WORDS - MD_SB_PERSONALITY_WORDS - MD_SB_DISKS_WORDS - MD_SB_DESCRIPTOR_WORDS)
+#define MD_SB_EQUAL_WORDS		(MD_SB_GENERIC_WORDS + MD_SB_PERSONALITY_WORDS + MD_SB_DISKS_WORDS)
+
+/*
+ * Device "operational" state bits
+ */
+#define MD_DISK_FAULTY		0 /* disk is faulty / operational */
+#define MD_DISK_ACTIVE		1 /* disk is running or spare disk */
+#define MD_DISK_SYNC		2 /* disk is in sync with the raid set */
+#define MD_DISK_REMOVED		3 /* disk is in sync with the raid set */
+
+typedef struct mdp_device_descriptor_s {
+	__u32 number;		/* 0 Device number in the entire set	      */
+	__u32 major;		/* 1 Device major number		      */
+	__u32 minor;		/* 2 Device minor number		      */
+	__u32 raid_disk;	/* 3 The role of the device in the raid set   */
+	__u32 state;		/* 4 Operational state			      */
+	__u32 reserved[MD_SB_DESCRIPTOR_WORDS - 5];
+} mdp_disk_t;
+
+#define MD_SB_MAGIC		0xa92b4efc
+
+/*
+ * Superblock state bits
+ */
+#define MD_SB_CLEAN		0
+#define MD_SB_ERRORS		1
+
+typedef struct mdp_superblock_s {
+	/*
+	 * Constant generic information
+	 */
+	__u32 md_magic;		/*  0 MD identifier 			      */
+	__u32 major_version;	/*  1 major version to which the set conforms */
+	__u32 minor_version;	/*  2 minor version ...			      */
+	__u32 patch_version;	/*  3 patchlevel version ...		      */
+	__u32 gvalid_words;	/*  4 Number of used words in this section    */
+	__u32 set_uuid0;	/*  5 Raid set identifier		      */
+	__u32 ctime;		/*  6 Creation time			      */
+	__u32 level;		/*  7 Raid personality			      */
+	__u32 size;		/*  8 Apparent size of each individual disk   */
+	__u32 nr_disks;		/*  9 total disks in the raid set	      */
+	__u32 raid_disks;	/* 10 disks in a fully functional raid set    */
+	__u32 md_minor;		/* 11 preferred MD minor device number	      */
+	__u32 not_persistent;	/* 12 does it have a persistent superblock    */
+	__u32 set_uuid1;	/* 13 Raid set identifier #2		      */
+	__u32 set_uuid2;	/* 14 Raid set identifier #3		      */
+	__u32 set_uuid3;	/* 15 Raid set identifier #4		      */
+	__u32 gstate_creserved[MD_SB_GENERIC_CONSTANT_WORDS - 16];
+
+	/*
+	 * Generic state information
+	 */
+	__u32 utime;		/*  0 Superblock update time		      */
+	__u32 state;		/*  1 State bits (clean, ...)		      */
+	__u32 active_disks;	/*  2 Number of currently active disks	      */
+	__u32 working_disks;	/*  3 Number of working disks		      */
+	__u32 failed_disks;	/*  4 Number of failed disks		      */
+	__u32 spare_disks;	/*  5 Number of spare disks		      */
+	__u32 sb_csum;		/*  6 checksum of the whole superblock        */
+#ifdef __BIG_ENDIAN
+	__u32 events_hi;	/*  7 high-order of superblock update count   */
+	__u32 events_lo;	/*  8 low-order of superblock update count    */
+	__u32 cp_events_hi;	/*  9 high-order of checkpoint update count   */
+	__u32 cp_events_lo;	/* 10 low-order of checkpoint update count    */
+#else
+	__u32 events_lo;	/*  7 low-order of superblock update count    */
+	__u32 events_hi;	/*  8 high-order of superblock update count   */
+	__u32 cp_events_lo;	/*  9 low-order of checkpoint update count    */
+	__u32 cp_events_hi;	/* 10 high-order of checkpoint update count   */
+#endif
+	__u32 recovery_cp;	/* 11 recovery checkpoint sector count	      */
+	__u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 12];
+
+	/*
+	 * Personality information
+	 */
+	__u32 layout;		/*  0 the array's physical layout	      */
+	__u32 chunk_size;	/*  1 chunk size in bytes		      */
+	__u32 root_pv;		/*  2 LV root PV */
+	__u32 root_block;	/*  3 LV root block */
+	__u32 pstate_reserved[MD_SB_PERSONALITY_WORDS - 4];
+
+	/*
+	 * Disks information
+	 */
+	mdp_disk_t disks[MD_SB_DISKS];
+
+	/*
+	 * Reserved
+	 */
+	__u32 reserved[MD_SB_RESERVED_WORDS];
+
+	/*
+	 * Active descriptor
+	 */
+	mdp_disk_t this_disk;
+
+} mdp_super_t;
+
+static inline __u64 md_event(mdp_super_t *sb) {
+	__u64 ev = sb->events_hi;
+	return (ev<<32)| sb->events_lo;
+}
+
+/*
+ * The version-1 superblock :
+ * All numeric fields are little-endian.
+ *
+ * total size: 256 bytes plus 2 per device.
+ *  1K allows 384 devices.
+ */
+struct mdp_superblock_1 {
+	/* constant array information - 128 bytes */
+	__u32	magic;		/* MD_SB_MAGIC: 0xa92b4efc - little endian */
+	__u32	major_version;	/* 1 */
+	__u32	feature_map;	/* 0 for now */
+	__u32	pad0;		/* always set to 0 when writing */
+
+	__u8	set_uuid[16];	/* user-space generated. */
+	char	set_name[32];	/* set and interpreted by user-space */
+
+	__u64	ctime;		/* lo 40 bits are seconds, top 24 are microseconds or 0*/
+	__u32	level;		/* -4 (multipath), -1 (linear), 0,1,4,5 */
+	__u32	layout;		/* only for raid5 currently */
+	__u64	size;		/* used size of component devices, in 512byte sectors */
+
+	__u32	chunksize;	/* in 512byte sectors */
+	__u32	raid_disks;
+	__u8	pad1[128-96];	/* set to 0 when written */
+
+	/* constant this-device information - 64 bytes */
+	__u64	data_offset;	/* sector start of data, often 0 */
+	__u64	data_size;	/* sectors in this device that can be used for data */
+	__u64	super_offset;	/* sector start of this superblock */
+	__u64	recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
+	__u32	dev_number;	/* permanent identifier of this  device - not role in raid */
+	__u32	cnt_corrected_read; /* number of read errors that were corrected by re-writing */
+	__u8	device_uuid[16]; /* user-space setable, ignored by kernel */
+	__u8	pad2[64-56];	/* set to 0 when writing */
+
+	/* array state information - 64 bytes */
+	__u64	utime;		/* 40 bits second, 24 btes microseconds */
+	__u64	events;		/* incremented when superblock updated */
+	__u64	resync_offset;	/* data before this offset (from data_offset) known to be in sync */
+	__u32	sb_csum;	/* checksum upto devs[max_dev] */
+	__u32	max_dev;	/* size of devs[] array to consider */
+	__u8	pad3[64-32];	/* set to 0 when writing */
+
+	/* device state information. Indexed by dev_number.
+	 * 2 bytes per device
+	 * Note there are no per-device state flags. State information is rolled
+	 * into the 'roles' value.  If a device is spare or faulty, then it doesn't
+	 * have a meaningful role.
+	 */
+	__u16	dev_roles[0];	/* role in array, or 0xffff for a spare, or 0xfffe for faulty */
+};
+
+#endif 
+
diff --git a/include/linux/raid/md_u.h b/include/linux/raid/md_u.h
new file mode 100644
index 0000000..a2df5c2
--- /dev/null
+++ b/include/linux/raid/md_u.h
@@ -0,0 +1,117 @@
+/*
+   md_u.h : user <=> kernel API between Linux raidtools and RAID drivers
+          Copyright (C) 1998 Ingo Molnar
+	  
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+   
+   You should have received a copy of the GNU General Public License
+   (for example /usr/src/linux/COPYING); if not, write to the Free
+   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
+*/
+
+#ifndef _MD_U_H
+#define _MD_U_H
+
+/* ioctls */
+
+/* status */
+#define RAID_VERSION		_IOR (MD_MAJOR, 0x10, mdu_version_t)
+#define GET_ARRAY_INFO		_IOR (MD_MAJOR, 0x11, mdu_array_info_t)
+#define GET_DISK_INFO		_IOR (MD_MAJOR, 0x12, mdu_disk_info_t)
+#define PRINT_RAID_DEBUG	_IO (MD_MAJOR, 0x13)
+#define RAID_AUTORUN		_IO (MD_MAJOR, 0x14)
+
+/* configuration */
+#define CLEAR_ARRAY		_IO (MD_MAJOR, 0x20)
+#define ADD_NEW_DISK		_IOW (MD_MAJOR, 0x21, mdu_disk_info_t)
+#define HOT_REMOVE_DISK		_IO (MD_MAJOR, 0x22)
+#define SET_ARRAY_INFO		_IOW (MD_MAJOR, 0x23, mdu_array_info_t)
+#define SET_DISK_INFO		_IO (MD_MAJOR, 0x24)
+#define WRITE_RAID_INFO		_IO (MD_MAJOR, 0x25)
+#define UNPROTECT_ARRAY		_IO (MD_MAJOR, 0x26)
+#define PROTECT_ARRAY		_IO (MD_MAJOR, 0x27)
+#define HOT_ADD_DISK		_IO (MD_MAJOR, 0x28)
+#define SET_DISK_FAULTY		_IO (MD_MAJOR, 0x29)
+#define HOT_GENERATE_ERROR	_IO (MD_MAJOR, 0x2a)
+
+/* usage */
+#define RUN_ARRAY		_IOW (MD_MAJOR, 0x30, mdu_param_t)
+#define START_ARRAY		_IO (MD_MAJOR, 0x31)
+#define STOP_ARRAY		_IO (MD_MAJOR, 0x32)
+#define STOP_ARRAY_RO		_IO (MD_MAJOR, 0x33)
+#define RESTART_ARRAY_RW	_IO (MD_MAJOR, 0x34)
+
+typedef struct mdu_version_s {
+	int major;
+	int minor;
+	int patchlevel;
+} mdu_version_t;
+
+typedef struct mdu_array_info_s {
+	/*
+	 * Generic constant information
+	 */
+	int major_version;
+	int minor_version;
+	int patch_version;
+	int ctime;
+	int level;
+	int size;
+	int nr_disks;
+	int raid_disks;
+	int md_minor;
+	int not_persistent;
+
+	/*
+	 * Generic state information
+	 */
+	int utime;		/*  0 Superblock update time		      */
+	int state;		/*  1 State bits (clean, ...)		      */
+	int active_disks;	/*  2 Number of currently active disks	      */
+	int working_disks;	/*  3 Number of working disks		      */
+	int failed_disks;	/*  4 Number of failed disks		      */
+	int spare_disks;	/*  5 Number of spare disks		      */
+
+	/*
+	 * Personality information
+	 */
+	int layout;		/*  0 the array's physical layout	      */
+	int chunk_size;	/*  1 chunk size in bytes		      */
+
+} mdu_array_info_t;
+
+typedef struct mdu_disk_info_s {
+	/*
+	 * configuration/status of one particular disk
+	 */
+	int number;
+	int major;
+	int minor;
+	int raid_disk;
+	int state;
+
+} mdu_disk_info_t;
+
+typedef struct mdu_start_info_s {
+	/*
+	 * configuration/status of one particular disk
+	 */
+	int major;
+	int minor;
+	int raid_disk;
+	int state;
+
+} mdu_start_info_t;
+
+typedef struct mdu_param_s
+{
+	int			personality;	/* 1,2,3,4 */
+	int			chunk_size;	/* in bytes */
+	int			max_fault;	/* unused for now */
+} mdu_param_t;
+
+#endif 
+
diff --git a/include/linux/raid/multipath.h b/include/linux/raid/multipath.h
new file mode 100644
index 0000000..6f53fc1
--- /dev/null
+++ b/include/linux/raid/multipath.h
@@ -0,0 +1,42 @@
+#ifndef _MULTIPATH_H
+#define _MULTIPATH_H
+
+#include <linux/raid/md.h>
+
+struct multipath_info {
+	mdk_rdev_t	*rdev;
+};
+
+struct multipath_private_data {
+	mddev_t			*mddev;
+	struct multipath_info	*multipaths;
+	int			raid_disks;
+	int			working_disks;
+	spinlock_t		device_lock;
+	struct list_head	retry_list;
+
+	mempool_t		*pool;
+};
+
+typedef struct multipath_private_data multipath_conf_t;
+
+/*
+ * this is the only point in the RAID code where we violate
+ * C type safety. mddev->private is an 'opaque' pointer.
+ */
+#define mddev_to_conf(mddev) ((multipath_conf_t *) mddev->private)
+
+/*
+ * this is our 'private' 'collective' MULTIPATH buffer head.
+ * it contains information about what kind of IO operations were started
+ * for this MULTIPATH operation, and about their status:
+ */
+
+struct multipath_bh {
+	mddev_t			*mddev;
+	struct bio		*master_bio;
+	struct bio		bio;
+	int			path;
+	struct list_head	retry_list;
+};
+#endif
diff --git a/include/linux/raid/raid0.h b/include/linux/raid/raid0.h
new file mode 100644
index 0000000..1b2dda0
--- /dev/null
+++ b/include/linux/raid/raid0.h
@@ -0,0 +1,30 @@
+#ifndef _RAID0_H
+#define _RAID0_H
+
+#include <linux/raid/md.h>
+
+struct strip_zone
+{
+	sector_t zone_offset;	/* Zone offset in md_dev */
+	sector_t dev_offset;	/* Zone offset in real dev */
+	sector_t size;		/* Zone size */
+	int nb_dev;		/* # of devices attached to the zone */
+	mdk_rdev_t **dev;	/* Devices attached to the zone */
+};
+
+struct raid0_private_data
+{
+	struct strip_zone **hash_table; /* Table of indexes into strip_zone */
+	struct strip_zone *strip_zone;
+	mdk_rdev_t **devlist; /* lists of rdevs, pointed to by strip_zone->dev */
+	int nr_strip_zones;
+
+	sector_t hash_spacing;
+	int preshift;			/* shift this before divide by hash_spacing */
+};
+
+typedef struct raid0_private_data raid0_conf_t;
+
+#define mddev_to_conf(mddev) ((raid0_conf_t *) mddev->private)
+
+#endif
diff --git a/include/linux/raid/raid1.h b/include/linux/raid/raid1.h
new file mode 100644
index 0000000..abbfdd9
--- /dev/null
+++ b/include/linux/raid/raid1.h
@@ -0,0 +1,98 @@
+#ifndef _RAID1_H
+#define _RAID1_H
+
+#include <linux/raid/md.h>
+
+typedef struct mirror_info mirror_info_t;
+
+struct mirror_info {
+	mdk_rdev_t	*rdev;
+	sector_t	head_position;
+};
+
+/*
+ * memory pools need a pointer to the mddev, so they can force an unplug
+ * when memory is tight, and a count of the number of drives that the
+ * pool was allocated for, so they know how much to allocate and free.
+ * mddev->raid_disks cannot be used, as it can change while a pool is active
+ * These two datums are stored in a kmalloced struct.
+ */
+
+struct pool_info {
+	mddev_t *mddev;
+	int	raid_disks;
+};
+
+
+typedef struct r1bio_s r1bio_t;
+
+struct r1_private_data_s {
+	mddev_t			*mddev;
+	mirror_info_t		*mirrors;
+	int			raid_disks;
+	int			working_disks;
+	int			last_used;
+	sector_t		next_seq_sect;
+	spinlock_t		device_lock;
+
+	struct list_head	retry_list;
+	/* for use when syncing mirrors: */
+
+	spinlock_t		resync_lock;
+	int nr_pending;
+	int barrier;
+	sector_t		next_resync;
+
+	wait_queue_head_t	wait_idle;
+	wait_queue_head_t	wait_resume;
+
+	struct pool_info	*poolinfo;
+
+	mempool_t *r1bio_pool;
+	mempool_t *r1buf_pool;
+};
+
+typedef struct r1_private_data_s conf_t;
+
+/*
+ * this is the only point in the RAID code where we violate
+ * C type safety. mddev->private is an 'opaque' pointer.
+ */
+#define mddev_to_conf(mddev) ((conf_t *) mddev->private)
+
+/*
+ * this is our 'private' RAID1 bio.
+ *
+ * it contains information about what kind of IO operations were started
+ * for this RAID1 operation, and about their status:
+ */
+
+struct r1bio_s {
+	atomic_t		remaining; /* 'have we finished' count,
+					    * used from IRQ handlers
+					    */
+	sector_t		sector;
+	int			sectors;
+	unsigned long		state;
+	mddev_t			*mddev;
+	/*
+	 * original bio going to /dev/mdx
+	 */
+	struct bio		*master_bio;
+	/*
+	 * if the IO is in READ direction, then this is where we read
+	 */
+	int			read_disk;
+
+	struct list_head	retry_list;
+	/*
+	 * if the IO is in WRITE direction, then multiple bios are used.
+	 * We choose the number when they are allocated.
+	 */
+	struct bio		*bios[0];
+};
+
+/* bits for r1bio.state */
+#define	R1BIO_Uptodate	0
+#define	R1BIO_IsSync	1
+#endif
diff --git a/include/linux/raid/raid10.h b/include/linux/raid/raid10.h
new file mode 100644
index 0000000..6070878
--- /dev/null
+++ b/include/linux/raid/raid10.h
@@ -0,0 +1,103 @@
+#ifndef _RAID10_H
+#define _RAID10_H
+
+#include <linux/raid/md.h>
+
+typedef struct mirror_info mirror_info_t;
+
+struct mirror_info {
+	mdk_rdev_t	*rdev;
+	sector_t	head_position;
+};
+
+typedef struct r10bio_s r10bio_t;
+
+struct r10_private_data_s {
+	mddev_t			*mddev;
+	mirror_info_t		*mirrors;
+	int			raid_disks;
+	int			working_disks;
+	spinlock_t		device_lock;
+
+	/* geometry */
+	int			near_copies;  /* number of copies layed out raid0 style */
+	int 			far_copies;   /* number of copies layed out
+					       * at large strides across drives
+					       */
+	int			copies;	      /* near_copies * far_copies.
+					       * must be <= raid_disks
+					       */
+	sector_t		stride;	      /* distance between far copies.
+					       * This is size / far_copies
+					       */
+
+	int chunk_shift; /* shift from chunks to sectors */
+	sector_t chunk_mask;
+
+	struct list_head	retry_list;
+	/* for use when syncing mirrors: */
+
+	spinlock_t		resync_lock;
+	int nr_pending;
+	int barrier;
+	sector_t		next_resync;
+
+	wait_queue_head_t	wait_idle;
+	wait_queue_head_t	wait_resume;
+
+	mempool_t *r10bio_pool;
+	mempool_t *r10buf_pool;
+};
+
+typedef struct r10_private_data_s conf_t;
+
+/*
+ * this is the only point in the RAID code where we violate
+ * C type safety. mddev->private is an 'opaque' pointer.
+ */
+#define mddev_to_conf(mddev) ((conf_t *) mddev->private)
+
+/*
+ * this is our 'private' RAID10 bio.
+ *
+ * it contains information about what kind of IO operations were started
+ * for this RAID10 operation, and about their status:
+ */
+
+struct r10bio_s {
+	atomic_t		remaining; /* 'have we finished' count,
+					    * used from IRQ handlers
+					    */
+	sector_t		sector;	/* virtual sector number */
+	int			sectors;
+	unsigned long		state;
+	mddev_t			*mddev;
+	/*
+	 * original bio going to /dev/mdx
+	 */
+	struct bio		*master_bio;
+	/*
+	 * if the IO is in READ direction, then this is where we read
+	 */
+	int			read_slot;
+
+	struct list_head	retry_list;
+	/*
+	 * if the IO is in WRITE direction, then multiple bios are used,
+	 * one for each copy.
+	 * When resyncing we also use one for each copy.
+	 * When reconstructing, we use 2 bios, one for read, one for write.
+	 * We choose the number when they are allocated.
+	 */
+	struct {
+		struct bio		*bio;
+		sector_t addr;
+		int devnum;
+	} devs[0];
+};
+
+/* bits for r10bio.state */
+#define	R10BIO_Uptodate	0
+#define	R10BIO_IsSync	1
+#define	R10BIO_IsRecover 2
+#endif
diff --git a/include/linux/raid/raid5.h b/include/linux/raid/raid5.h
new file mode 100644
index 0000000..d63ddcb
--- /dev/null
+++ b/include/linux/raid/raid5.h
@@ -0,0 +1,243 @@
+#ifndef _RAID5_H
+#define _RAID5_H
+
+#include <linux/raid/md.h>
+#include <linux/raid/xor.h>
+
+/*
+ *
+ * Each stripe contains one buffer per disc.  Each buffer can be in
+ * one of a number of states stored in "flags".  Changes between
+ * these states happen *almost* exclusively under a per-stripe
+ * spinlock.  Some very specific changes can happen in bi_end_io, and
+ * these are not protected by the spin lock.
+ *
+ * The flag bits that are used to represent these states are:
+ *   R5_UPTODATE and R5_LOCKED
+ *
+ * State Empty == !UPTODATE, !LOCK
+ *        We have no data, and there is no active request
+ * State Want == !UPTODATE, LOCK
+ *        A read request is being submitted for this block
+ * State Dirty == UPTODATE, LOCK
+ *        Some new data is in this buffer, and it is being written out
+ * State Clean == UPTODATE, !LOCK
+ *        We have valid data which is the same as on disc
+ *
+ * The possible state transitions are:
+ *
+ *  Empty -> Want   - on read or write to get old data for  parity calc
+ *  Empty -> Dirty  - on compute_parity to satisfy write/sync request.(RECONSTRUCT_WRITE)
+ *  Empty -> Clean  - on compute_block when computing a block for failed drive
+ *  Want  -> Empty  - on failed read
+ *  Want  -> Clean  - on successful completion of read request
+ *  Dirty -> Clean  - on successful completion of write request
+ *  Dirty -> Clean  - on failed write
+ *  Clean -> Dirty  - on compute_parity to satisfy write/sync (RECONSTRUCT or RMW)
+ *
+ * The Want->Empty, Want->Clean, Dirty->Clean, transitions
+ * all happen in b_end_io at interrupt time.
+ * Each sets the Uptodate bit before releasing the Lock bit.
+ * This leaves one multi-stage transition:
+ *    Want->Dirty->Clean
+ * This is safe because thinking that a Clean buffer is actually dirty
+ * will at worst delay some action, and the stripe will be scheduled
+ * for attention after the transition is complete.
+ *
+ * There is one possibility that is not covered by these states.  That
+ * is if one drive has failed and there is a spare being rebuilt.  We
+ * can't distinguish between a clean block that has been generated
+ * from parity calculations, and a clean block that has been
+ * successfully written to the spare ( or to parity when resyncing).
+ * To distingush these states we have a stripe bit STRIPE_INSYNC that
+ * is set whenever a write is scheduled to the spare, or to the parity
+ * disc if there is no spare.  A sync request clears this bit, and
+ * when we find it set with no buffers locked, we know the sync is
+ * complete.
+ *
+ * Buffers for the md device that arrive via make_request are attached
+ * to the appropriate stripe in one of two lists linked on b_reqnext.
+ * One list (bh_read) for read requests, one (bh_write) for write.
+ * There should never be more than one buffer on the two lists
+ * together, but we are not guaranteed of that so we allow for more.
+ *
+ * If a buffer is on the read list when the associated cache buffer is
+ * Uptodate, the data is copied into the read buffer and it's b_end_io
+ * routine is called.  This may happen in the end_request routine only
+ * if the buffer has just successfully been read.  end_request should
+ * remove the buffers from the list and then set the Uptodate bit on
+ * the buffer.  Other threads may do this only if they first check
+ * that the Uptodate bit is set.  Once they have checked that they may
+ * take buffers off the read queue.
+ *
+ * When a buffer on the write list is committed for write it is copied
+ * into the cache buffer, which is then marked dirty, and moved onto a
+ * third list, the written list (bh_written).  Once both the parity
+ * block and the cached buffer are successfully written, any buffer on
+ * a written list can be returned with b_end_io.
+ *
+ * The write list and read list both act as fifos.  The read list is
+ * protected by the device_lock.  The write and written lists are
+ * protected by the stripe lock.  The device_lock, which can be
+ * claimed while the stipe lock is held, is only for list
+ * manipulations and will only be held for a very short time.  It can
+ * be claimed from interrupts.
+ *
+ *
+ * Stripes in the stripe cache can be on one of two lists (or on
+ * neither).  The "inactive_list" contains stripes which are not
+ * currently being used for any request.  They can freely be reused
+ * for another stripe.  The "handle_list" contains stripes that need
+ * to be handled in some way.  Both of these are fifo queues.  Each
+ * stripe is also (potentially) linked to a hash bucket in the hash
+ * table so that it can be found by sector number.  Stripes that are
+ * not hashed must be on the inactive_list, and will normally be at
+ * the front.  All stripes start life this way.
+ *
+ * The inactive_list, handle_list and hash bucket lists are all protected by the
+ * device_lock.
+ *  - stripes on the inactive_list never have their stripe_lock held.
+ *  - stripes have a reference counter. If count==0, they are on a list.
+ *  - If a stripe might need handling, STRIPE_HANDLE is set.
+ *  - When refcount reaches zero, then if STRIPE_HANDLE it is put on
+ *    handle_list else inactive_list
+ *
+ * This, combined with the fact that STRIPE_HANDLE is only ever
+ * cleared while a stripe has a non-zero count means that if the
+ * refcount is 0 and STRIPE_HANDLE is set, then it is on the
+ * handle_list and if recount is 0 and STRIPE_HANDLE is not set, then
+ * the stripe is on inactive_list.
+ *
+ * The possible transitions are:
+ *  activate an unhashed/inactive stripe (get_active_stripe())
+ *     lockdev check-hash unlink-stripe cnt++ clean-stripe hash-stripe unlockdev
+ *  activate a hashed, possibly active stripe (get_active_stripe())
+ *     lockdev check-hash if(!cnt++)unlink-stripe unlockdev
+ *  attach a request to an active stripe (add_stripe_bh())
+ *     lockdev attach-buffer unlockdev
+ *  handle a stripe (handle_stripe())
+ *     lockstripe clrSTRIPE_HANDLE ... (lockdev check-buffers unlockdev) .. change-state .. record io needed unlockstripe schedule io
+ *  release an active stripe (release_stripe())
+ *     lockdev if (!--cnt) { if  STRIPE_HANDLE, add to handle_list else add to inactive-list } unlockdev
+ *
+ * The refcount counts each thread that have activated the stripe,
+ * plus raid5d if it is handling it, plus one for each active request
+ * on a cached buffer.
+ */
+
+struct stripe_head {
+	struct stripe_head	*hash_next, **hash_pprev; /* hash pointers */
+	struct list_head	lru;			/* inactive_list or handle_list */
+	struct raid5_private_data	*raid_conf;
+	sector_t		sector;			/* sector of this row */
+	int			pd_idx;			/* parity disk index */
+	unsigned long		state;			/* state flags */
+	atomic_t		count;			/* nr of active thread/requests */
+	spinlock_t		lock;
+	struct r5dev {
+		struct bio	req;
+		struct bio_vec	vec;
+		struct page	*page;
+		struct bio	*toread, *towrite, *written;
+		sector_t	sector;			/* sector of this page */
+		unsigned long	flags;
+	} dev[1]; /* allocated with extra space depending of RAID geometry */
+};
+/* Flags */
+#define	R5_UPTODATE	0	/* page contains current data */
+#define	R5_LOCKED	1	/* IO has been submitted on "req" */
+#define	R5_OVERWRITE	2	/* towrite covers whole page */
+/* and some that are internal to handle_stripe */
+#define	R5_Insync	3	/* rdev && rdev->in_sync at start */
+#define	R5_Wantread	4	/* want to schedule a read */
+#define	R5_Wantwrite	5
+#define	R5_Syncio	6	/* this io need to be accounted as resync io */
+#define	R5_Overlap	7	/* There is a pending overlapping request on this block */
+
+/*
+ * Write method
+ */
+#define RECONSTRUCT_WRITE	1
+#define READ_MODIFY_WRITE	2
+/* not a write method, but a compute_parity mode */
+#define	CHECK_PARITY		3
+
+/*
+ * Stripe state
+ */
+#define STRIPE_ERROR		1
+#define STRIPE_HANDLE		2
+#define	STRIPE_SYNCING		3
+#define	STRIPE_INSYNC		4
+#define	STRIPE_PREREAD_ACTIVE	5
+#define	STRIPE_DELAYED		6
+
+/*
+ * Plugging:
+ *
+ * To improve write throughput, we need to delay the handling of some
+ * stripes until there has been a chance that several write requests
+ * for the one stripe have all been collected.
+ * In particular, any write request that would require pre-reading
+ * is put on a "delayed" queue until there are no stripes currently
+ * in a pre-read phase.  Further, if the "delayed" queue is empty when
+ * a stripe is put on it then we "plug" the queue and do not process it
+ * until an unplug call is made. (the unplug_io_fn() is called).
+ *
+ * When preread is initiated on a stripe, we set PREREAD_ACTIVE and add
+ * it to the count of prereading stripes.
+ * When write is initiated, or the stripe refcnt == 0 (just in case) we
+ * clear the PREREAD_ACTIVE flag and decrement the count
+ * Whenever the delayed queue is empty and the device is not plugged, we
+ * move any strips from delayed to handle and clear the DELAYED flag and set PREREAD_ACTIVE.
+ * In stripe_handle, if we find pre-reading is necessary, we do it if
+ * PREREAD_ACTIVE is set, else we set DELAYED which will send it to the delayed queue.
+ * HANDLE gets cleared if stripe_handle leave nothing locked.
+ */
+ 
+
+struct disk_info {
+	mdk_rdev_t	*rdev;
+};
+
+struct raid5_private_data {
+	struct stripe_head	**stripe_hashtbl;
+	mddev_t			*mddev;
+	struct disk_info	*spare;
+	int			chunk_size, level, algorithm;
+	int			raid_disks, working_disks, failed_disks;
+	int			max_nr_stripes;
+
+	struct list_head	handle_list; /* stripes needing handling */
+	struct list_head	delayed_list; /* stripes that have plugged requests */
+	atomic_t		preread_active_stripes; /* stripes with scheduled io */
+
+	char			cache_name[20];
+	kmem_cache_t		*slab_cache; /* for allocating stripes */
+	/*
+	 * Free stripes pool
+	 */
+	atomic_t		active_stripes;
+	struct list_head	inactive_list;
+	wait_queue_head_t	wait_for_stripe;
+	wait_queue_head_t	wait_for_overlap;
+	int			inactive_blocked;	/* release of inactive stripes blocked,
+							 * waiting for 25% to be free
+							 */        
+	spinlock_t		device_lock;
+	struct disk_info	disks[0];
+};
+
+typedef struct raid5_private_data raid5_conf_t;
+
+#define mddev_to_conf(mddev) ((raid5_conf_t *) mddev->private)
+
+/*
+ * Our supported algorithms
+ */
+#define ALGORITHM_LEFT_ASYMMETRIC	0
+#define ALGORITHM_RIGHT_ASYMMETRIC	1
+#define ALGORITHM_LEFT_SYMMETRIC	2
+#define ALGORITHM_RIGHT_SYMMETRIC	3
+
+#endif
diff --git a/include/linux/raid/xor.h b/include/linux/raid/xor.h
new file mode 100644
index 0000000..f0d67cb
--- /dev/null
+++ b/include/linux/raid/xor.h
@@ -0,0 +1,23 @@
+#ifndef _XOR_H
+#define _XOR_H
+
+#include <linux/raid/md.h>
+
+#define MAX_XOR_BLOCKS 5
+
+extern void xor_block(unsigned int count, unsigned int bytes, void **ptr);
+
+struct xor_block_template {
+        struct xor_block_template *next;
+        const char *name;
+        int speed;
+	void (*do_2)(unsigned long, unsigned long *, unsigned long *);
+	void (*do_3)(unsigned long, unsigned long *, unsigned long *,
+		     unsigned long *);
+	void (*do_4)(unsigned long, unsigned long *, unsigned long *,
+		     unsigned long *, unsigned long *);
+	void (*do_5)(unsigned long, unsigned long *, unsigned long *,
+		     unsigned long *, unsigned long *, unsigned long *);
+};
+
+#endif