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Edit File: genhd.h

/* SPDX-License-Identifier: GPL-2.0 */ #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> #include <linux/percpu-refcount.h> #include <linux/uuid.h> #include <linux/blk_types.h> #include <asm/local.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 { u64 nsecs[NR_STAT_GROUPS]; unsigned long sectors[NR_STAT_GROUPS]; unsigned long ios[NR_STAT_GROUPS]; unsigned long merges[NR_STAT_GROUPS]; unsigned long io_ticks; unsigned long time_in_queue; local_t in_flight[2]; }; #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 (UUID_STRING_LEN + 1) 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; #ifdef CONFIG_SMP struct disk_stats __percpu *dkstats; #else struct disk_stats dkstats; #endif struct percpu_ref ref; struct rcu_work rcu_work; }; #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 #define GENHD_FL_HIDDEN 1024 enum { DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */ }; enum { /* Poll even if events_poll_msecs is unset */ DISK_EVENT_FLAG_POLL = 1 << 0, /* Forward events to udev */ DISK_EVENT_FLAG_UEVENT = 1 << 1, }; 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 badblocks; #if defined(CONFIG_BLK_DEV_INTEGRITY) struct blk_integrity { const struct blk_integrity_profile *profile; unsigned char flags; unsigned char tuple_size; unsigned char interval_exp; unsigned char tag_size; }; #endif /* CONFIG_BLK_DEV_INTEGRITY */ 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 short events; /* supported events */ unsigned short event_flags; /* flags related to event processing */ /* 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 rw_semaphore lookup_sem; struct kobject *slave_dir; struct timer_rand_state *random; atomic_t sync_io; /* RAID */ struct disk_events *ev; #ifdef CONFIG_BLK_DEV_INTEGRITY struct kobject integrity_kobj; #endif /* CONFIG_BLK_DEV_INTEGRITY */ int node_id; struct badblocks *bb; struct lockdep_map lockdep_map; }; 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 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 MKDEV(disk->major, disk->first_minor); } 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); 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_get_cpu(part, field, cpu) \ (per_cpu_ptr((part)->dkstats, (cpu))->field) #define part_stat_get(part, field) \ part_stat_get_cpu(part, field, smp_processor_id()) #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_get(part, field) ((part)->dkstats.field) #define part_stat_get_cpu(part, field, cpu) part_stat_get(part, field) #define part_stat_read(part, field) part_stat_get(part, 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_read_msecs(part, which) \ div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC) #define part_stat_read_accum(part, field) \ (part_stat_read(part, field[STAT_READ]) + \ part_stat_read(part, field[STAT_WRITE]) + \ part_stat_read(part, field[STAT_DISCARD])) #define __part_stat_add(part, field, addnd) \ (part_stat_get(part, field) += (addnd)) #define part_stat_add(part, field, addnd) do { \ __part_stat_add((part), field, addnd); \ if ((part)->partno) \ __part_stat_add(&part_to_disk((part))->part0, \ field, addnd); \ } while (0) #define part_stat_dec(gendiskp, field) \ part_stat_add(gendiskp, field, -1) #define part_stat_inc(gendiskp, field) \ part_stat_add(gendiskp, field, 1) #define part_stat_sub(gendiskp, field, subnd) \ part_stat_add(gendiskp, field, -subnd) #define part_stat_local_dec(gendiskp, field) \ local_dec(&(part_stat_get(gendiskp, field))) #define part_stat_local_inc(gendiskp, field) \ local_inc(&(part_stat_get(gendiskp, field))) #define part_stat_local_read(gendiskp, field) \ local_read(&(part_stat_get(gendiskp, field))) #define part_stat_local_read_cpu(gendiskp, field, cpu) \ local_read(&(part_stat_get_cpu(gendiskp, field, cpu))) unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part); void part_in_flight_rw(struct request_queue *q, struct hd_struct *part, unsigned int inflight[2]); void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw); void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw); 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); } void update_io_ticks(struct hd_struct *part, unsigned long now, bool end); /* block/genhd.c */ extern void device_add_disk(struct device *parent, struct gendisk *disk, const struct attribute_group **groups); static inline void add_disk(struct gendisk *disk) { device_add_disk(NULL, disk, NULL); } extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk); static inline void add_disk_no_queue_reg(struct gendisk *disk) { device_add_disk_no_queue_reg(NULL, 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) __latent_entropy; 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 void blk_invalidate_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 percpu_ref *); 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 kobject *get_disk_and_module(struct gendisk *disk); extern void put_disk(struct gendisk *disk); extern void put_disk_and_module(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 */ #define alloc_disk_node(minors, node_id) \ ({ \ static struct lock_class_key __key; \ const char *__name; \ struct gendisk *__disk; \ \ __name = "(gendisk_completion)"#minors"("#node_id")"; \ \ __disk = __alloc_disk_node(minors, node_id); \ \ if (__disk) \ lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \ \ __disk; \ }) #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE) static inline int hd_ref_init(struct hd_struct *part) { if (percpu_ref_init(&part->ref, __delete_partition, 0, GFP_KERNEL)) return -ENOMEM; return 0; } static inline void hd_struct_get(struct hd_struct *part) { percpu_ref_get(&part->ref); } static inline int hd_struct_try_get(struct hd_struct *part) { return percpu_ref_tryget_live(&part->ref); } static inline void hd_struct_put(struct hd_struct *part) { percpu_ref_put(&part->ref); } static inline void hd_struct_kill(struct hd_struct *part) { percpu_ref_kill(&part->ref); } static inline void hd_free_part(struct hd_struct *part) { free_part_stats(part); free_part_info(part); percpu_ref_exit(&part->ref); } /* * 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_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_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_SMP) preempt_disable(); write_seqcount_begin(&part->nr_sects_seq); part->nr_sects = size; write_seqcount_end(&part->nr_sects_seq); preempt_enable(); #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) preempt_disable(); part->nr_sects = size; preempt_enable(); #else part->nr_sects = size; #endif } #if defined(CONFIG_BLK_DEV_INTEGRITY) extern void blk_integrity_add(struct gendisk *); extern void blk_integrity_del(struct gendisk *); #else /* CONFIG_BLK_DEV_INTEGRITY */ static inline void blk_integrity_add(struct gendisk *disk) { } static inline void blk_integrity_del(struct gendisk *disk) { } #endif /* CONFIG_BLK_DEV_INTEGRITY */ #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; } #endif /* CONFIG_BLOCK */ #endif /* _LINUX_GENHD_H */