diff options
| -rw-r--r-- | fs/nilfs2/nilfs.h | 323 | ||||
| -rw-r--r-- | fs/nilfs2/sb.h | 102 | ||||
| -rw-r--r-- | fs/nilfs2/the_nilfs.h | 290 |
3 files changed, 715 insertions, 0 deletions
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h new file mode 100644 index 00000000000..17458ad4a80 --- /dev/null +++ b/fs/nilfs2/nilfs.h @@ -0,0 +1,323 @@ +/* + * nilfs.h - NILFS local header file. + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * 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 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Koji Sato <koji@osrg.net> + * Ryusuke Konishi <ryusuke@osrg.net> + */ + +#ifndef _NILFS_H +#define _NILFS_H + +#include <linux/kernel.h> +#include <linux/buffer_head.h> +#include <linux/spinlock.h> +#include <linux/blkdev.h> +#include <linux/nilfs2_fs.h> +#include "the_nilfs.h" +#include "sb.h" +#include "bmap.h" +#include "bmap_union.h" + +/* + * NILFS filesystem version + */ +#define NILFS_VERSION "2.0.5" + +/* + * nilfs inode data in memory + */ +struct nilfs_inode_info { + __u32 i_flags; + unsigned long i_state; /* Dynamic state flags */ + struct nilfs_bmap *i_bmap; + union nilfs_bmap_union i_bmap_union; + __u64 i_xattr; /* sector_t ??? */ + __u32 i_dtime; + __u32 i_dir_start_lookup; + __u64 i_cno; /* check point number for GC inode */ + struct address_space i_btnode_cache; + struct list_head i_dirty; /* List for connecting dirty files */ + +#ifdef CONFIG_NILFS_XATTR + /* + * Extended attributes can be read independently of the main file + * data. Taking i_sem even when reading would cause contention + * between readers of EAs and writers of regular file data, so + * instead we synchronize on xattr_sem when reading or changing + * EAs. + */ + struct rw_semaphore xattr_sem; +#endif +#ifdef CONFIG_NILFS_POSIX_ACL + struct posix_acl *i_acl; + struct posix_acl *i_default_acl; +#endif + struct buffer_head *i_bh; /* i_bh contains a new or dirty + disk inode */ + struct inode vfs_inode; +}; + +static inline struct nilfs_inode_info *NILFS_I(const struct inode *inode) +{ + return container_of(inode, struct nilfs_inode_info, vfs_inode); +} + +static inline struct nilfs_inode_info * +NILFS_BMAP_I(const struct nilfs_bmap *bmap) +{ + return container_of((union nilfs_bmap_union *)bmap, + struct nilfs_inode_info, + i_bmap_union); +} + +static inline struct inode *NILFS_BTNC_I(struct address_space *btnc) +{ + struct nilfs_inode_info *ii = + container_of(btnc, struct nilfs_inode_info, i_btnode_cache); + return &ii->vfs_inode; +} + +static inline struct inode *NILFS_AS_I(struct address_space *mapping) +{ + return (mapping->host) ? : + container_of(mapping, struct inode, i_data); +} + +/* + * Dynamic state flags of NILFS on-memory inode (i_state) + */ +enum { + NILFS_I_NEW = 0, /* Inode is newly created */ + NILFS_I_DIRTY, /* The file is dirty */ + NILFS_I_QUEUED, /* inode is in dirty_files list */ + NILFS_I_BUSY, /* inode is grabbed by a segment + constructor */ + NILFS_I_COLLECTED, /* All dirty blocks are collected */ + NILFS_I_UPDATED, /* The file has been written back */ + NILFS_I_INODE_DIRTY, /* write_inode is requested */ + NILFS_I_BMAP, /* has bmap and btnode_cache */ + NILFS_I_GCINODE, /* inode for GC, on memory only */ + NILFS_I_GCDAT, /* shadow DAT, on memory only */ +}; + +/* + * Macros to check inode numbers + */ +#define NILFS_MDT_INO_BITS \ + ((unsigned int)(1 << NILFS_DAT_INO | 1 << NILFS_CPFILE_INO | \ + 1 << NILFS_SUFILE_INO | 1 << NILFS_IFILE_INO | \ + 1 << NILFS_ATIME_INO | 1 << NILFS_SKETCH_INO)) + +#define NILFS_SYS_INO_BITS \ + ((unsigned int)(1 << NILFS_ROOT_INO) | NILFS_MDT_INO_BITS) + +#define NILFS_FIRST_INO(sb) (NILFS_SB(sb)->s_nilfs->ns_first_ino) + +#define NILFS_MDT_INODE(sb, ino) \ + ((ino) < NILFS_FIRST_INO(sb) && (NILFS_MDT_INO_BITS & (1 << (ino)))) +#define NILFS_VALID_INODE(sb, ino) \ + ((ino) >= NILFS_FIRST_INO(sb) || (NILFS_SYS_INO_BITS & (1 << (ino)))) + +/** + * struct nilfs_transaction_info: context information for synchronization + * @ti_magic: Magic number + * @ti_save: Backup of journal_info field of task_struct + * @ti_flags: Flags + * @ti_count: Nest level + * @ti_garbage: List of inode to be put when releasing semaphore + */ +struct nilfs_transaction_info { + u32 ti_magic; + void *ti_save; + /* This should never used. If this happens, + one of other filesystems has a bug. */ + unsigned short ti_flags; + unsigned short ti_count; + struct list_head ti_garbage; +}; + +/* ti_magic */ +#define NILFS_TI_MAGIC 0xd9e392fb + +/* ti_flags */ +#define NILFS_TI_DYNAMIC_ALLOC 0x0001 /* Allocated from slab */ +#define NILFS_TI_SYNC 0x0002 /* Force to construct segment at the + end of transaction. */ +#define NILFS_TI_GC 0x0004 /* GC context */ +#define NILFS_TI_COMMIT 0x0008 /* Change happened or not */ +#define NILFS_TI_WRITER 0x0010 /* Constructor context */ + + +int nilfs_transaction_begin(struct super_block *, + struct nilfs_transaction_info *, int); +int nilfs_transaction_end(struct super_block *, int); + +static inline void nilfs_set_transaction_flag(unsigned int flag) +{ + struct nilfs_transaction_info *ti = current->journal_info; + + BUG_ON(!ti); + ti->ti_flags |= flag; +} + +static inline int nilfs_test_transaction_flag(unsigned int flag) +{ + struct nilfs_transaction_info *ti = current->journal_info; + + if (ti == NULL || ti->ti_magic != NILFS_TI_MAGIC) + return 0; + return !!(ti->ti_flags & flag); +} + +static inline int nilfs_doing_gc(void) +{ + return nilfs_test_transaction_flag(NILFS_TI_GC); +} + +static inline int nilfs_doing_construction(void) +{ + return nilfs_test_transaction_flag(NILFS_TI_WRITER); +} + +static inline struct inode *nilfs_dat_inode(const struct the_nilfs *nilfs) +{ + return nilfs_doing_gc() ? nilfs->ns_gc_dat : nilfs->ns_dat; +} + +/* + * function prototype + */ +#ifdef CONFIG_NILFS_POSIX_ACL +#error "NILFS: not yet supported POSIX ACL" +extern int nilfs_permission(struct inode *, int, struct nameidata *); +extern int nilfs_acl_chmod(struct inode *); +extern int nilfs_init_acl(struct inode *, struct inode *); +#else +#define nilfs_permission NULL + +static inline int nilfs_acl_chmod(struct inode *inode) +{ + return 0; +} + +static inline int nilfs_init_acl(struct inode *inode, struct inode *dir) +{ + inode->i_mode &= ~current_umask(); + return 0; +} +#endif + +#define NILFS_ATIME_DISABLE + +/* dir.c */ +extern int nilfs_add_link(struct dentry *, struct inode *); +extern ino_t nilfs_inode_by_name(struct inode *, struct dentry *); +extern int nilfs_make_empty(struct inode *, struct inode *); +extern struct nilfs_dir_entry * +nilfs_find_entry(struct inode *, struct dentry *, struct page **); +extern int nilfs_delete_entry(struct nilfs_dir_entry *, struct page *); +extern int nilfs_empty_dir(struct inode *); +extern struct nilfs_dir_entry *nilfs_dotdot(struct inode *, struct page **); +extern void nilfs_set_link(struct inode *, struct nilfs_dir_entry *, + struct page *, struct inode *); + +/* file.c */ +extern int nilfs_sync_file(struct file *, struct dentry *, int); + +/* ioctl.c */ +int nilfs_ioctl(struct inode *, struct file *, unsigned int, unsigned long); +long nilfs_compat_ioctl(struct file *, unsigned int, unsigned long); +int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *, void __user *); + +/* inode.c */ +extern struct inode *nilfs_new_inode(struct inode *, int); +extern void nilfs_free_inode(struct inode *); +extern int nilfs_get_block(struct inode *, sector_t, struct buffer_head *, int); +extern void nilfs_set_inode_flags(struct inode *); +extern int nilfs_read_inode_common(struct inode *, struct nilfs_inode *); +extern void nilfs_write_inode_common(struct inode *, struct nilfs_inode *, int); +extern struct inode *nilfs_iget(struct super_block *, unsigned long); +extern void nilfs_update_inode(struct inode *, struct buffer_head *); +extern void nilfs_truncate(struct inode *); +extern void nilfs_delete_inode(struct inode *); +extern int nilfs_setattr(struct dentry *, struct iattr *); +extern int nilfs_load_inode_block(struct nilfs_sb_info *, struct inode *, + struct buffer_head **); +extern int nilfs_inode_dirty(struct inode *); +extern int nilfs_set_file_dirty(struct nilfs_sb_info *, struct inode *, + unsigned); +extern int nilfs_mark_inode_dirty(struct inode *); +extern void nilfs_dirty_inode(struct inode *); + +/* namei.c */ +extern struct dentry *nilfs_get_parent(struct dentry *); + +/* super.c */ +extern struct inode *nilfs_alloc_inode(struct super_block *); +extern void nilfs_destroy_inode(struct inode *); +extern void nilfs_error(struct super_block *, const char *, const char *, ...) + __attribute__ ((format (printf, 3, 4))); +extern void nilfs_warning(struct super_block *, const char *, const char *, ...) + __attribute__ ((format (printf, 3, 4))); +extern struct nilfs_super_block * +nilfs_load_super_block(struct super_block *, struct buffer_head **); +extern struct nilfs_super_block * +nilfs_reload_super_block(struct super_block *, struct buffer_head **, int); +extern int nilfs_store_magic_and_option(struct super_block *, + struct nilfs_super_block *, char *); +extern void nilfs_update_last_segment(struct nilfs_sb_info *, int); +extern int nilfs_commit_super(struct nilfs_sb_info *); +extern int nilfs_attach_checkpoint(struct nilfs_sb_info *, __u64); +extern void nilfs_detach_checkpoint(struct nilfs_sb_info *); + +/* gcinode.c */ +int nilfs_gccache_submit_read_data(struct inode *, sector_t, sector_t, __u64, + struct buffer_head **); +int nilfs_gccache_submit_read_node(struct inode *, sector_t, __u64, + struct buffer_head **); +int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *); +int nilfs_init_gccache(struct the_nilfs *); +void nilfs_destroy_gccache(struct the_nilfs *); +void nilfs_clear_gcinode(struct inode *); +struct inode *nilfs_gc_iget(struct the_nilfs *, ino_t, __u64); +void nilfs_remove_all_gcinode(struct the_nilfs *); + +/* gcdat.c */ +int nilfs_init_gcdat_inode(struct the_nilfs *); +void nilfs_commit_gcdat_inode(struct the_nilfs *); +void nilfs_clear_gcdat_inode(struct the_nilfs *); + +/* + * Inodes and files operations + */ +extern struct file_operations nilfs_dir_operations; +extern struct inode_operations nilfs_file_inode_operations; +extern struct file_operations nilfs_file_operations; +extern struct address_space_operations nilfs_aops; +extern struct inode_operations nilfs_dir_inode_operations; +extern struct inode_operations nilfs_special_inode_operations; +extern struct inode_operations nilfs_symlink_inode_operations; + +/* + * filesystem type + */ +extern struct file_system_type nilfs_fs_type; + + +#endif /* _NILFS_H */ diff --git a/fs/nilfs2/sb.h b/fs/nilfs2/sb.h new file mode 100644 index 00000000000..adccd4fc654 --- /dev/null +++ b/fs/nilfs2/sb.h @@ -0,0 +1,102 @@ +/* + * sb.h - NILFS on-memory super block structure. + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * 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 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Ryusuke Konishi <ryusuke@osrg.net> + * + */ + +#ifndef _NILFS_SB +#define _NILFS_SB + +#include <linux/types.h> +#include <linux/fs.h> + +/* + * Mount options + */ +struct nilfs_mount_options { + unsigned long mount_opt; + __u64 snapshot_cno; +}; + +struct the_nilfs; +struct nilfs_sc_info; + +/* + * NILFS super-block data in memory + */ +struct nilfs_sb_info { + /* Snapshot status */ + __u64 s_snapshot_cno; /* Checkpoint number */ + atomic_t s_inodes_count; + atomic_t s_blocks_count; /* Reserved (might be deleted) */ + + /* Mount options */ + unsigned long s_mount_opt; + uid_t s_resuid; + gid_t s_resgid; + + unsigned long s_interval; /* construction interval */ + unsigned long s_watermark; /* threshold of data amount + for the segment construction */ + + /* Fundamental members */ + struct super_block *s_super; /* reverse pointer to super_block */ + struct the_nilfs *s_nilfs; + struct list_head s_list; /* list head for nilfs->ns_supers */ + + /* Segment constructor */ + struct list_head s_dirty_files; /* dirty files list */ + struct nilfs_sc_info *s_sc_info; /* segment constructor info */ + spinlock_t s_inode_lock; /* Lock for the nilfs inode. + It covers s_dirty_files list */ + + /* Metadata files */ + struct inode *s_ifile; /* index file inode */ + + /* Inode allocator */ + spinlock_t s_next_gen_lock; + u32 s_next_generation; +}; + +static inline struct nilfs_sb_info *NILFS_SB(struct super_block *sb) +{ + return sb->s_fs_info; +} + +static inline struct nilfs_sc_info *NILFS_SC(struct nilfs_sb_info *sbi) +{ + return sbi->s_sc_info; +} + +/* + * Bit operations for the mount option + */ +#define nilfs_clear_opt(sbi, opt) \ + do { (sbi)->s_mount_opt &= ~NILFS_MOUNT_##opt; } while (0) +#define nilfs_set_opt(sbi, opt) \ + do { (sbi)->s_mount_opt |= NILFS_MOUNT_##opt; } while (0) +#define nilfs_test_opt(sbi, opt) ((sbi)->s_mount_opt & NILFS_MOUNT_##opt) +#define nilfs_write_opt(sbi, mask, opt) \ + do { (sbi)->s_mount_opt = \ + (((sbi)->s_mount_opt & ~NILFS_MOUNT_##mask) | \ + NILFS_MOUNT_##opt); \ + } while (0) + +#endif /* _NILFS_SB */ diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h new file mode 100644 index 00000000000..dee8d83e054 --- /dev/null +++ b/fs/nilfs2/the_nilfs.h @@ -0,0 +1,290 @@ +/* + * the_nilfs.h - the_nilfs shared structure. + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * 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 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Ryusuke Konishi <ryusuke@osrg.net> + * + */ + +#ifndef _THE_NILFS_H +#define _THE_NILFS_H + +#include <linux/types.h> +#include <linux/buffer_head.h> +#include <linux/fs.h> +#include <linux/blkdev.h> +#include <linux/backing-dev.h> +#include "sb.h" + +/* the_nilfs struct */ +enum { + THE_NILFS_INIT = 0, /* Information from super_block is set */ + THE_NILFS_LOADED, /* Roll-back/roll-forward has done and + the latest checkpoint was loaded */ + THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */ + THE_NILFS_COND_NONGC_WRITE, /* Condition to wake up cleanerd */ +}; + +/** + * struct the_nilfs - struct to supervise multiple nilfs mount points + * @ns_flags: flags + * @ns_count: reference count + * @ns_bdev: block device + * @ns_bdi: backing dev info + * @ns_writer: back pointer to writable nilfs_sb_info + * @ns_sem: semaphore for shared states + * @ns_writer_mutex: mutex protecting ns_writer attach/detach + * @ns_writer_refcount: number of referrers on ns_writer + * @ns_sbh: buffer head of the on-disk super block + * @ns_sbp: pointer to the super block data + * @ns_used_segments: list of full segments in volatile active state + * @ns_supers: list of nilfs super block structs + * @ns_seg_seq: segment sequence counter + * @ns_segnum: index number of the latest full segment. + * @ns_nextnum: index number of the full segment index to be used next + * @ns_pseg_offset: offset of next partial segment in the current full segment + * @ns_cno: next checkpoint number + * @ns_ctime: write time of the last segment + * @ns_nongc_ctime: write time of the last segment not for cleaner operation + * @ns_ndirtyblks: Number of dirty data blocks + * @ns_last_segment_lock: lock protecting fields for the latest segment + * @ns_last_pseg: start block number of the latest segment + * @ns_last_seq: sequence value of the latest segment + * @ns_last_cno: checkpoint number of the latest segment + * @ns_free_segments_count: counter of free segments + * @ns_segctor_sem: segment constructor semaphore + * @ns_dat: DAT file inode + * @ns_cpfile: checkpoint file inode + * @ns_sufile: segusage file inode + * @ns_gc_dat: shadow inode of the DAT file inode for GC + * @ns_gc_inodes: dummy inodes to keep live blocks + * @ns_gc_inodes_h: hash list to keep dummy inode holding live blocks + * @ns_cleanerd_wq: wait queue for cleanerd + * @ns_blocksize_bits: bit length of block size + * @ns_nsegments: number of segments in filesystem + * @ns_blocks_per_segment: number of blocks per segment + * @ns_r_segments_percentage: reserved segments percentage + * @ns_nrsvsegs: number of reserved segments + * @ns_first_data_block: block number of first data block + * @ns_inode_size: size of on-disk inode + * @ns_first_ino: first not-special inode number + * @ns_crc_seed: seed value of CRC32 calculation + */ +struct the_nilfs { + unsigned long ns_flags; + atomic_t ns_count; + + struct block_device *ns_bdev; + struct backing_dev_info *ns_bdi; + struct nilfs_sb_info *ns_writer; + struct rw_semaphore ns_sem; + struct mutex ns_writer_mutex; + atomic_t ns_writer_refcount; + + /* + * used for + * - loading the latest checkpoint exclusively. + * - allocating a new full segment. + * - protecting s_dirt in the super_block struct + * (see nilfs_write_super) and the following fields. + */ + struct buffer_head *ns_sbh; + struct nilfs_super_block *ns_sbp; + struct list_head ns_used_segments; + unsigned ns_mount_state; + struct list_head ns_supers; + + /* + * Following fields are dedicated to a writable FS-instance. + * Except for the period seeking checkpoint, code outside the segment + * constructor must lock a segment semaphore with transaction_begin() + * and transaction_end(), when accessing these fields. + * The writable FS-instance is sole during a lifetime of the_nilfs. + */ + u64 ns_seg_seq; + __u64 ns_segnum; + __u64 ns_nextnum; + unsigned long ns_pseg_offset; + __u64 ns_cno; + time_t ns_ctime; + time_t ns_nongc_ctime; + atomic_t ns_ndirtyblks; + + /* + * The following fields hold information on the latest partial segment + * written to disk with a super root. These fields are protected by + * ns_last_segment_lock. + */ + spinlock_t ns_last_segment_lock; + sector_t ns_last_pseg; + u64 ns_last_seq; + __u64 ns_last_cno; + unsigned long ns_free_segments_count; + + struct rw_semaphore ns_segctor_sem; + + /* + * Following fields are lock free except for the period before + * the_nilfs is initialized. + */ + struct inode *ns_dat; + struct inode *ns_cpfile; + struct inode *ns_sufile; + struct inode *ns_gc_dat; + + /* GC inode list and hash table head */ + struct list_head ns_gc_inodes; + struct hlist_head *ns_gc_inodes_h; + + /* cleanerd */ + wait_queue_head_t ns_cleanerd_wq; + + /* Disk layout information (static) */ + unsigned int ns_blocksize_bits; + unsigned long ns_nsegments; + unsigned long ns_blocks_per_segment; + unsigned long ns_r_segments_percentage; + unsigned long ns_nrsvsegs; + unsigned long ns_first_data_block; + int ns_inode_size; + int ns_first_ino; + u32 ns_crc_seed; +}; + +#define NILFS_GCINODE_HASH_BITS 8 +#define NILFS_GCINODE_HASH_SIZE (1<<NILFS_GCINODE_HASH_BITS) + +#define THE_NILFS_FNS(bit, name) \ +static inline void set_nilfs_##name(struct the_nilfs *nilfs) \ +{ \ + set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \ +} \ +static inline void clear_nilfs_##name(struct the_nilfs *nilfs) \ +{ \ + clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \ +} \ +static inline int nilfs_##name(struct the_nilfs *nilfs) \ +{ \ + return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \ +} + +THE_NILFS_FNS(INIT, init) +THE_NILFS_FNS(LOADED, loaded) +THE_NILFS_FNS(DISCONTINUED, discontinued) +THE_NILFS_FNS(COND_NONGC_WRITE, cond_nongc_write) + +void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64); +struct the_nilfs *alloc_nilfs(struct block_device *); +void put_nilfs(struct the_nilfs *); +int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *); +int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *); +int nilfs_count_free_blocks(struct the_nilfs *, sector_t *); +void nilfs_dispose_used_segments(struct the_nilfs *); +int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int); +int nilfs_near_disk_full(struct the_nilfs *); + + +static inline void get_nilfs(struct the_nilfs *nilfs) +{ + /* Caller must have at least one reference of the_nilfs. */ + atomic_inc(&nilfs->ns_count); +} + +static inline struct nilfs_sb_info *nilfs_get_writer(struct the_nilfs *nilfs) +{ + if (atomic_inc_and_test(&nilfs->ns_writer_refcount)) + mutex_lock(&nilfs->ns_writer_mutex); + return nilfs->ns_writer; +} + +static inline void nilfs_put_writer(struct the_nilfs *nilfs) +{ + if (atomic_add_negative(-1, &nilfs->ns_writer_refcount)) + mutex_unlock(&nilfs->ns_writer_mutex); +} + +static inline void +nilfs_attach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) +{ + mutex_lock(&nilfs->ns_writer_mutex); + nilfs->ns_writer = sbi; + mutex_unlock(&nilfs->ns_writer_mutex); +} + +static inline void +nilfs_detach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) +{ + mutex_lock(&nilfs->ns_writer_mutex); + if (sbi == nilfs->ns_writer) + nilfs->ns_writer = NULL; + mutex_unlock(&nilfs->ns_writer_mutex); +} + +static inline void +nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum, + sector_t *seg_start, sector_t *seg_end) +{ + *seg_start = (sector_t)nilfs->ns_blocks_per_segment * segnum; + *seg_end = *seg_start + nilfs->ns_blocks_per_segment - 1; + if (segnum == 0) + *seg_start = nilfs->ns_first_data_block; +} + +static inline sector_t +nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum) +{ + return (segnum == 0) ? nilfs->ns_first_data_block : + (sector_t)nilfs->ns_blocks_per_segment * segnum; +} + +static inline __u64 +nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr) +{ + sector_t segnum = blocknr; + + sector_div(segnum, nilfs->ns_blocks_per_segment); + return segnum; +} + +static inline void +nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start, + sector_t seg_end) +{ + /* terminate the current full segment (used in case of I/O-error) */ + nilfs->ns_pseg_offset = seg_end - seg_start + 1; +} + +static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs) +{ + /* move forward with a full segment */ + nilfs->ns_segnum = nilfs->ns_nextnum; + nilfs->ns_pseg_offset = 0; + nilfs->ns_seg_seq++; +} + +static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs) +{ + __u64 cno; + + spin_lock(&nilfs->ns_last_segment_lock); + cno = nilfs->ns_last_cno; + spin_unlock(&nilfs->ns_last_segment_lock); + return cno; +} + +#endif /* _THE_NILFS_H */ |