--- /dev/null
+#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 */
Code Review / kvmfornfv.git / blobdiff