Initial import

1 files changed, 733 insertions, 0 deletions

diff --git a/include/linux/genhd.h b/include/linux/genhd.h
new file mode 100644
index 000000000..ec274e0f4
--- /dev/null
+++ b/include/linux/genhd.h
@@ -0,0 +1,733 @@
+#ifndef _LINUX_GENHD_H
+#define _LINUX_GENHD_H
+
+/*
+ * 	genhd.h Copyright (C) 1992 Drew Eckhardt
+ *	Generic hard disk header file by  
+ * 		Drew Eckhardt
+ *
+ *		<drew@colorado.edu>
+ */
+
+#include <linux/types.h>
+#include <linux/kdev_t.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+
+#ifdef CONFIG_BLOCK
+
+#define dev_to_disk(device)	container_of((device), struct gendisk, part0.__dev)
+#define dev_to_part(device)	container_of((device), struct hd_struct, __dev)
+#define disk_to_dev(disk)	(&(disk)->part0.__dev)
+#define part_to_dev(part)	(&((part)->__dev))
+
+extern struct device_type part_type;
+extern struct kobject *block_depr;
+extern struct class block_class;
+
+enum {
+/* These three have identical behaviour; use the second one if DOS FDISK gets
+   confused about extended/logical partitions starting past cylinder 1023. */
+	DOS_EXTENDED_PARTITION = 5,
+	LINUX_EXTENDED_PARTITION = 0x85,
+	WIN98_EXTENDED_PARTITION = 0x0f,
+
+	SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
+
+	LINUX_SWAP_PARTITION = 0x82,
+	LINUX_DATA_PARTITION = 0x83,
+	LINUX_LVM_PARTITION = 0x8e,
+	LINUX_RAID_PARTITION = 0xfd,	/* autodetect RAID partition */
+
+	SOLARIS_X86_PARTITION =	LINUX_SWAP_PARTITION,
+	NEW_SOLARIS_X86_PARTITION = 0xbf,
+
+	DM6_AUX1PARTITION = 0x51,	/* no DDO:  use xlated geom */
+	DM6_AUX3PARTITION = 0x53,	/* no DDO:  use xlated geom */
+	DM6_PARTITION =	0x54,		/* has DDO: use xlated geom & offset */
+	EZD_PARTITION =	0x55,		/* EZ-DRIVE */
+
+	FREEBSD_PARTITION = 0xa5,	/* FreeBSD Partition ID */
+	OPENBSD_PARTITION = 0xa6,	/* OpenBSD Partition ID */
+	NETBSD_PARTITION = 0xa9,	/* NetBSD Partition ID */
+	BSDI_PARTITION = 0xb7,		/* BSDI Partition ID */
+	MINIX_PARTITION = 0x81,		/* Minix Partition ID */
+	UNIXWARE_PARTITION = 0x63,	/* Same as GNU_HURD and SCO Unix */
+};
+
+#define DISK_MAX_PARTS			256
+#define DISK_NAME_LEN			32
+
+#include <linux/major.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/workqueue.h>
+
+struct partition {
+	unsigned char boot_ind;		/* 0x80 - active */
+	unsigned char head;		/* starting head */
+	unsigned char sector;		/* starting sector */
+	unsigned char cyl;		/* starting cylinder */
+	unsigned char sys_ind;		/* What partition type */
+	unsigned char end_head;		/* end head */
+	unsigned char end_sector;	/* end sector */
+	unsigned char end_cyl;		/* end cylinder */
+	__le32 start_sect;	/* starting sector counting from 0 */
+	__le32 nr_sects;		/* nr of sectors in partition */
+} __attribute__((packed));
+
+struct disk_stats {
+	unsigned long sectors[2];	/* READs and WRITEs */
+	unsigned long ios[2];
+	unsigned long merges[2];
+	unsigned long ticks[2];
+	unsigned long io_ticks;
+	unsigned long time_in_queue;
+};
+
+#define PARTITION_META_INFO_VOLNAMELTH	64
+/*
+ * Enough for the string representation of any kind of UUID plus NULL.
+ * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
+ */
+#define PARTITION_META_INFO_UUIDLTH	37
+
+struct partition_meta_info {
+	char uuid[PARTITION_META_INFO_UUIDLTH];
+	u8 volname[PARTITION_META_INFO_VOLNAMELTH];
+};
+
+struct hd_struct {
+	sector_t start_sect;
+	/*
+	 * nr_sects is protected by sequence counter. One might extend a
+	 * partition while IO is happening to it and update of nr_sects
+	 * can be non-atomic on 32bit machines with 64bit sector_t.
+	 */
+	sector_t nr_sects;
+	seqcount_t nr_sects_seq;
+	sector_t alignment_offset;
+	unsigned int discard_alignment;
+	struct device __dev;
+	struct kobject *holder_dir;
+	int policy, partno;
+	struct partition_meta_info *info;
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+	int make_it_fail;
+#endif
+	unsigned long stamp;
+	atomic_t in_flight[2];
+#ifdef	CONFIG_SMP
+	struct disk_stats __percpu *dkstats;
+#else
+	struct disk_stats dkstats;
+#endif
+	atomic_t ref;
+	struct rcu_head rcu_head;
+};
+
+#define GENHD_FL_REMOVABLE			1
+/* 2 is unused */
+#define GENHD_FL_MEDIA_CHANGE_NOTIFY		4
+#define GENHD_FL_CD				8
+#define GENHD_FL_UP				16
+#define GENHD_FL_SUPPRESS_PARTITION_INFO	32
+#define GENHD_FL_EXT_DEVT			64 /* allow extended devt */
+#define GENHD_FL_NATIVE_CAPACITY		128
+#define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE	256
+#define GENHD_FL_NO_PART_SCAN			512
+
+enum {
+	DISK_EVENT_MEDIA_CHANGE			= 1 << 0, /* media changed */
+	DISK_EVENT_EJECT_REQUEST		= 1 << 1, /* eject requested */
+};
+
+#define BLK_SCSI_MAX_CMDS	(256)
+#define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
+
+struct blk_scsi_cmd_filter {
+	unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
+	unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
+	struct kobject kobj;
+};
+
+struct disk_part_tbl {
+	struct rcu_head rcu_head;
+	int len;
+	struct hd_struct __rcu *last_lookup;
+	struct hd_struct __rcu *part[];
+};
+
+struct disk_events;
+
+struct gendisk {
+	/* major, first_minor and minors are input parameters only,
+	 * don't use directly.  Use disk_devt() and disk_max_parts().
+	 */
+	int major;			/* major number of driver */
+	int first_minor;
+	int minors;                     /* maximum number of minors, =1 for
+                                         * disks that can't be partitioned. */
+
+	char disk_name[DISK_NAME_LEN];	/* name of major driver */
+	char *(*devnode)(struct gendisk *gd, umode_t *mode);
+
+	unsigned int events;		/* supported events */
+	unsigned int async_events;	/* async events, subset of all */
+
+	/* Array of pointers to partitions indexed by partno.
+	 * Protected with matching bdev lock but stat and other
+	 * non-critical accesses use RCU.  Always access through
+	 * helpers.
+	 */
+	struct disk_part_tbl __rcu *part_tbl;
+	struct hd_struct part0;
+
+	const struct block_device_operations *fops;
+	struct request_queue *queue;
+	void *private_data;
+
+	int flags;
+	struct device *driverfs_dev;  // FIXME: remove
+	struct kobject *slave_dir;
+
+	struct timer_rand_state *random;
+	atomic_t sync_io;		/* RAID */
+	struct disk_events *ev;
+#ifdef  CONFIG_BLK_DEV_INTEGRITY
+	struct blk_integrity *integrity;
+#endif
+	int node_id;
+};
+
+static inline struct gendisk *part_to_disk(struct hd_struct *part)
+{
+	if (likely(part)) {
+		if (part->partno)
+			return dev_to_disk(part_to_dev(part)->parent);
+		else
+			return dev_to_disk(part_to_dev(part));
+	}
+	return NULL;
+}
+
+static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
+{
+	int i;
+	for (i = 0; i < 16; ++i) {
+		*to++ = (hex_to_bin(*uuid_str) << 4) |
+			(hex_to_bin(*(uuid_str + 1)));
+		uuid_str += 2;
+		switch (i) {
+		case 3:
+		case 5:
+		case 7:
+		case 9:
+			uuid_str++;
+			continue;
+		}
+	}
+}
+
+static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
+{
+	part_pack_uuid(uuid_str, to);
+	return 0;
+}
+
+static inline int disk_max_parts(struct gendisk *disk)
+{
+	if (disk->flags & GENHD_FL_EXT_DEVT)
+		return DISK_MAX_PARTS;
+	return disk->minors;
+}
+
+static inline bool disk_part_scan_enabled(struct gendisk *disk)
+{
+	return disk_max_parts(disk) > 1 &&
+		!(disk->flags & GENHD_FL_NO_PART_SCAN);
+}
+
+static inline dev_t disk_devt(struct gendisk *disk)
+{
+	return disk_to_dev(disk)->devt;
+}
+
+static inline dev_t part_devt(struct hd_struct *part)
+{
+	return part_to_dev(part)->devt;
+}
+
+extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
+
+static inline void disk_put_part(struct hd_struct *part)
+{
+	if (likely(part))
+		put_device(part_to_dev(part));
+}
+
+/*
+ * Smarter partition iterator without context limits.
+ */
+#define DISK_PITER_REVERSE	(1 << 0) /* iterate in the reverse direction */
+#define DISK_PITER_INCL_EMPTY	(1 << 1) /* include 0-sized parts */
+#define DISK_PITER_INCL_PART0	(1 << 2) /* include partition 0 */
+#define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
+
+struct disk_part_iter {
+	struct gendisk		*disk;
+	struct hd_struct	*part;
+	int			idx;
+	unsigned int		flags;
+};
+
+extern void disk_part_iter_init(struct disk_part_iter *piter,
+				 struct gendisk *disk, unsigned int flags);
+extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
+extern void disk_part_iter_exit(struct disk_part_iter *piter);
+
+extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
+					     sector_t sector);
+
+/*
+ * Macros to operate on percpu disk statistics:
+ *
+ * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
+ * and should be called between disk_stat_lock() and
+ * disk_stat_unlock().
+ *
+ * part_stat_read() can be called at any time.
+ *
+ * part_stat_{add|set_all}() and {init|free}_part_stats are for
+ * internal use only.
+ */
+#ifdef	CONFIG_SMP
+#define part_stat_lock()	({ rcu_read_lock(); get_cpu(); })
+#define part_stat_unlock()	do { put_cpu(); rcu_read_unlock(); } while (0)
+
+#define __part_stat_add(cpu, part, field, addnd)			\
+	(per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
+
+#define part_stat_read(part, field)					\
+({									\
+	typeof((part)->dkstats->field) res = 0;				\
+	unsigned int _cpu;						\
+	for_each_possible_cpu(_cpu)					\
+		res += per_cpu_ptr((part)->dkstats, _cpu)->field;	\
+	res;								\
+})
+
+static inline void part_stat_set_all(struct hd_struct *part, int value)
+{
+	int i;
+
+	for_each_possible_cpu(i)
+		memset(per_cpu_ptr(part->dkstats, i), value,
+				sizeof(struct disk_stats));
+}
+
+static inline int init_part_stats(struct hd_struct *part)
+{
+	part->dkstats = alloc_percpu(struct disk_stats);
+	if (!part->dkstats)
+		return 0;
+	return 1;
+}
+
+static inline void free_part_stats(struct hd_struct *part)
+{
+	free_percpu(part->dkstats);
+}
+
+#else /* !CONFIG_SMP */
+#define part_stat_lock()	({ rcu_read_lock(); 0; })
+#define part_stat_unlock()	rcu_read_unlock()
+
+#define __part_stat_add(cpu, part, field, addnd)				\
+	((part)->dkstats.field += addnd)
+
+#define part_stat_read(part, field)	((part)->dkstats.field)
+
+static inline void part_stat_set_all(struct hd_struct *part, int value)
+{
+	memset(&part->dkstats, value, sizeof(struct disk_stats));
+}
+
+static inline int init_part_stats(struct hd_struct *part)
+{
+	return 1;
+}
+
+static inline void free_part_stats(struct hd_struct *part)
+{
+}
+
+#endif /* CONFIG_SMP */
+
+#define part_stat_add(cpu, part, field, addnd)	do {			\
+	__part_stat_add((cpu), (part), field, addnd);			\
+	if ((part)->partno)						\
+		__part_stat_add((cpu), &part_to_disk((part))->part0,	\
+				field, addnd);				\
+} while (0)
+
+#define part_stat_dec(cpu, gendiskp, field)				\
+	part_stat_add(cpu, gendiskp, field, -1)
+#define part_stat_inc(cpu, gendiskp, field)				\
+	part_stat_add(cpu, gendiskp, field, 1)
+#define part_stat_sub(cpu, gendiskp, field, subnd)			\
+	part_stat_add(cpu, gendiskp, field, -subnd)
+
+static inline void part_inc_in_flight(struct hd_struct *part, int rw)
+{
+	atomic_inc(&part->in_flight[rw]);
+	if (part->partno)
+		atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
+}
+
+static inline void part_dec_in_flight(struct hd_struct *part, int rw)
+{
+	atomic_dec(&part->in_flight[rw]);
+	if (part->partno)
+		atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
+}
+
+static inline int part_in_flight(struct hd_struct *part)
+{
+	return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
+}
+
+static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
+{
+	if (disk)
+		return kzalloc_node(sizeof(struct partition_meta_info),
+				    GFP_KERNEL, disk->node_id);
+	return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
+}
+
+static inline void free_part_info(struct hd_struct *part)
+{
+	kfree(part->info);
+}
+
+/* block/blk-core.c */
+extern void part_round_stats(int cpu, struct hd_struct *part);
+
+/* block/genhd.c */
+extern void add_disk(struct gendisk *disk);
+extern void del_gendisk(struct gendisk *gp);
+extern struct gendisk *get_gendisk(dev_t dev, int *partno);
+extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
+
+extern void set_device_ro(struct block_device *bdev, int flag);
+extern void set_disk_ro(struct gendisk *disk, int flag);
+
+static inline int get_disk_ro(struct gendisk *disk)
+{
+	return disk->part0.policy;
+}
+
+extern void disk_block_events(struct gendisk *disk);
+extern void disk_unblock_events(struct gendisk *disk);
+extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
+extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
+
+/* drivers/char/random.c */
+extern void add_disk_randomness(struct gendisk *disk);
+extern void rand_initialize_disk(struct gendisk *disk);
+
+static inline sector_t get_start_sect(struct block_device *bdev)
+{
+	return bdev->bd_part->start_sect;
+}
+static inline sector_t get_capacity(struct gendisk *disk)
+{
+	return disk->part0.nr_sects;
+}
+static inline void set_capacity(struct gendisk *disk, sector_t size)
+{
+	disk->part0.nr_sects = size;
+}
+
+#ifdef CONFIG_SOLARIS_X86_PARTITION
+
+#define SOLARIS_X86_NUMSLICE	16
+#define SOLARIS_X86_VTOC_SANE	(0x600DDEEEUL)
+
+struct solaris_x86_slice {
+	__le16 s_tag;		/* ID tag of partition */
+	__le16 s_flag;		/* permission flags */
+	__le32 s_start;		/* start sector no of partition */
+	__le32 s_size;		/* # of blocks in partition */
+};
+
+struct solaris_x86_vtoc {
+	unsigned int v_bootinfo[3];	/* info needed by mboot (unsupported) */
+	__le32 v_sanity;		/* to verify vtoc sanity */
+	__le32 v_version;		/* layout version */
+	char	v_volume[8];		/* volume name */
+	__le16	v_sectorsz;		/* sector size in bytes */
+	__le16	v_nparts;		/* number of partitions */
+	unsigned int v_reserved[10];	/* free space */
+	struct solaris_x86_slice
+		v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
+	unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
+	char	v_asciilabel[128];	/* for compatibility */
+};
+
+#endif /* CONFIG_SOLARIS_X86_PARTITION */
+
+#ifdef CONFIG_BSD_DISKLABEL
+/*
+ * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
+ * updated by Marc Espie <Marc.Espie@openbsd.org>
+ */
+
+/* check against BSD src/sys/sys/disklabel.h for consistency */
+
+#define BSD_DISKMAGIC	(0x82564557UL)	/* The disk magic number */
+#define BSD_MAXPARTITIONS	16
+#define OPENBSD_MAXPARTITIONS	16
+#define BSD_FS_UNUSED		0	/* disklabel unused partition entry ID */
+struct bsd_disklabel {
+	__le32	d_magic;		/* the magic number */
+	__s16	d_type;			/* drive type */
+	__s16	d_subtype;		/* controller/d_type specific */
+	char	d_typename[16];		/* type name, e.g. "eagle" */
+	char	d_packname[16];			/* pack identifier */ 
+	__u32	d_secsize;		/* # of bytes per sector */
+	__u32	d_nsectors;		/* # of data sectors per track */
+	__u32	d_ntracks;		/* # of tracks per cylinder */
+	__u32	d_ncylinders;		/* # of data cylinders per unit */
+	__u32	d_secpercyl;		/* # of data sectors per cylinder */
+	__u32	d_secperunit;		/* # of data sectors per unit */
+	__u16	d_sparespertrack;	/* # of spare sectors per track */
+	__u16	d_sparespercyl;		/* # of spare sectors per cylinder */
+	__u32	d_acylinders;		/* # of alt. cylinders per unit */
+	__u16	d_rpm;			/* rotational speed */
+	__u16	d_interleave;		/* hardware sector interleave */
+	__u16	d_trackskew;		/* sector 0 skew, per track */
+	__u16	d_cylskew;		/* sector 0 skew, per cylinder */
+	__u32	d_headswitch;		/* head switch time, usec */
+	__u32	d_trkseek;		/* track-to-track seek, usec */
+	__u32	d_flags;		/* generic flags */
+#define NDDATA 5
+	__u32	d_drivedata[NDDATA];	/* drive-type specific information */
+#define NSPARE 5
+	__u32	d_spare[NSPARE];	/* reserved for future use */
+	__le32	d_magic2;		/* the magic number (again) */
+	__le16	d_checksum;		/* xor of data incl. partitions */
+
+			/* filesystem and partition information: */
+	__le16	d_npartitions;		/* number of partitions in following */
+	__le32	d_bbsize;		/* size of boot area at sn0, bytes */
+	__le32	d_sbsize;		/* max size of fs superblock, bytes */
+	struct	bsd_partition {		/* the partition table */
+		__le32	p_size;		/* number of sectors in partition */
+		__le32	p_offset;	/* starting sector */
+		__le32	p_fsize;	/* filesystem basic fragment size */
+		__u8	p_fstype;	/* filesystem type, see below */
+		__u8	p_frag;		/* filesystem fragments per block */
+		__le16	p_cpg;		/* filesystem cylinders per group */
+	} d_partitions[BSD_MAXPARTITIONS];	/* actually may be more */
+};
+
+#endif	/* CONFIG_BSD_DISKLABEL */
+
+#ifdef CONFIG_UNIXWARE_DISKLABEL
+/*
+ * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
+ * and Krzysztof G. Baranowski <kgb@knm.org.pl>
+ */
+
+#define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)	/* The disk magic number */
+#define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)	/* The slice table magic nr */
+#define UNIXWARE_NUMSLICE      16
+#define UNIXWARE_FS_UNUSED     0		/* Unused slice entry ID */
+
+struct unixware_slice {
+	__le16   s_label;	/* label */
+	__le16   s_flags;	/* permission flags */
+	__le32   start_sect;	/* starting sector */
+	__le32   nr_sects;	/* number of sectors in slice */
+};
+
+struct unixware_disklabel {
+	__le32   d_type;               	/* drive type */
+	__le32   d_magic;                /* the magic number */
+	__le32   d_version;              /* version number */
+	char    d_serial[12];           /* serial number of the device */
+	__le32   d_ncylinders;           /* # of data cylinders per device */
+	__le32   d_ntracks;              /* # of tracks per cylinder */
+	__le32   d_nsectors;             /* # of data sectors per track */
+	__le32   d_secsize;              /* # of bytes per sector */
+	__le32   d_part_start;           /* # of first sector of this partition */
+	__le32   d_unknown1[12];         /* ? */
+ 	__le32	d_alt_tbl;              /* byte offset of alternate table */
+ 	__le32	d_alt_len;              /* byte length of alternate table */
+ 	__le32	d_phys_cyl;             /* # of physical cylinders per device */
+ 	__le32	d_phys_trk;             /* # of physical tracks per cylinder */
+ 	__le32	d_phys_sec;             /* # of physical sectors per track */
+ 	__le32	d_phys_bytes;           /* # of physical bytes per sector */
+ 	__le32	d_unknown2;             /* ? */
+	__le32   d_unknown3;             /* ? */
+	__le32	d_pad[8];               /* pad */
+
+	struct unixware_vtoc {
+		__le32	v_magic;		/* the magic number */
+		__le32	v_version;		/* version number */
+		char	v_name[8];		/* volume name */
+		__le16	v_nslices;		/* # of slices */
+		__le16	v_unknown1;		/* ? */
+		__le32	v_reserved[10];		/* reserved */
+		struct unixware_slice
+			v_slice[UNIXWARE_NUMSLICE];	/* slice headers */
+	} vtoc;
+
+};  /* 408 */
+
+#endif /* CONFIG_UNIXWARE_DISKLABEL */
+
+#ifdef CONFIG_MINIX_SUBPARTITION
+#   define MINIX_NR_SUBPARTITIONS  4
+#endif /* CONFIG_MINIX_SUBPARTITION */
+
+#define ADDPART_FLAG_NONE	0
+#define ADDPART_FLAG_RAID	1
+#define ADDPART_FLAG_WHOLEDISK	2
+
+extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
+extern void blk_free_devt(dev_t devt);
+extern dev_t blk_lookup_devt(const char *name, int partno);
+extern char *disk_name (struct gendisk *hd, int partno, char *buf);
+
+extern int disk_expand_part_tbl(struct gendisk *disk, int target);
+extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
+extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
+extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
+						     int partno, sector_t start,
+						     sector_t len, int flags,
+						     struct partition_meta_info
+						       *info);
+extern void __delete_partition(struct hd_struct *);
+extern void delete_partition(struct gendisk *, int);
+extern void printk_all_partitions(void);
+
+extern struct gendisk *alloc_disk_node(int minors, int node_id);
+extern struct gendisk *alloc_disk(int minors);
+extern struct kobject *get_disk(struct gendisk *disk);
+extern void put_disk(struct gendisk *disk);
+extern void blk_register_region(dev_t devt, unsigned long range,
+			struct module *module,
+			struct kobject *(*probe)(dev_t, int *, void *),
+			int (*lock)(dev_t, void *),
+			void *data);
+extern void blk_unregister_region(dev_t devt, unsigned long range);
+
+extern ssize_t part_size_show(struct device *dev,
+			      struct device_attribute *attr, char *buf);
+extern ssize_t part_stat_show(struct device *dev,
+			      struct device_attribute *attr, char *buf);
+extern ssize_t part_inflight_show(struct device *dev,
+			      struct device_attribute *attr, char *buf);
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+extern ssize_t part_fail_show(struct device *dev,
+			      struct device_attribute *attr, char *buf);
+extern ssize_t part_fail_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count);
+#endif /* CONFIG_FAIL_MAKE_REQUEST */
+
+static inline void hd_ref_init(struct hd_struct *part)
+{
+	atomic_set(&part->ref, 1);
+	smp_mb();
+}
+
+static inline void hd_struct_get(struct hd_struct *part)
+{
+	atomic_inc(&part->ref);
+	smp_mb__after_atomic();
+}
+
+static inline int hd_struct_try_get(struct hd_struct *part)
+{
+	return atomic_inc_not_zero(&part->ref);
+}
+
+static inline void hd_struct_put(struct hd_struct *part)
+{
+	if (atomic_dec_and_test(&part->ref))
+		__delete_partition(part);
+}
+
+/*
+ * Any access of part->nr_sects which is not protected by partition
+ * bd_mutex or gendisk bdev bd_mutex, should be done using this
+ * accessor function.
+ *
+ * Code written along the lines of i_size_read() and i_size_write().
+ * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
+ * on.
+ */
+static inline sector_t part_nr_sects_read(struct hd_struct *part)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
+	sector_t nr_sects;
+	unsigned seq;
+	do {
+		seq = read_seqcount_begin(&part->nr_sects_seq);
+		nr_sects = part->nr_sects;
+	} while (read_seqcount_retry(&part->nr_sects_seq, seq));
+	return nr_sects;
+#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
+	sector_t nr_sects;
+
+	preempt_disable();
+	nr_sects = part->nr_sects;
+	preempt_enable();
+	return nr_sects;
+#else
+	return part->nr_sects;
+#endif
+}
+
+/*
+ * Should be called with mutex lock held (typically bd_mutex) of partition
+ * to provide mutual exlusion among writers otherwise seqcount might be
+ * left in wrong state leaving the readers spinning infinitely.
+ */
+static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
+	write_seqcount_begin(&part->nr_sects_seq);
+	part->nr_sects = size;
+	write_seqcount_end(&part->nr_sects_seq);
+#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
+	preempt_disable();
+	part->nr_sects = size;
+	preempt_enable();
+#else
+	part->nr_sects = size;
+#endif
+}
+
+#else /* CONFIG_BLOCK */
+
+static inline void printk_all_partitions(void) { }
+
+static inline dev_t blk_lookup_devt(const char *name, int partno)
+{
+	dev_t devt = MKDEV(0, 0);
+	return devt;
+}
+
+static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_BLOCK */
+
+#endif /* _LINUX_GENHD_H */