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Diffstat (limited to 'fs/logfs/logfs.h')
| -rw-r--r-- | fs/logfs/logfs.h | 724 |
1 files changed, 724 insertions, 0 deletions
diff --git a/fs/logfs/logfs.h b/fs/logfs/logfs.h new file mode 100644 index 00000000000..12977943137 --- /dev/null +++ b/fs/logfs/logfs.h @@ -0,0 +1,724 @@ +/* + * fs/logfs/logfs.h + * + * As should be obvious for Linux kernel code, license is GPLv2 + * + * Copyright (c) 2005-2008 Joern Engel <joern@logfs.org> + * + * Private header for logfs. + */ +#ifndef FS_LOGFS_LOGFS_H +#define FS_LOGFS_LOGFS_H + +#undef __CHECK_ENDIAN__ +#define __CHECK_ENDIAN__ + +#include <linux/btree.h> +#include <linux/crc32.h> +#include <linux/fs.h> +#include <linux/kernel.h> +#include <linux/mempool.h> +#include <linux/pagemap.h> +#include <linux/mtd/mtd.h> +#include "logfs_abi.h" + +#define LOGFS_DEBUG_SUPER (0x0001) +#define LOGFS_DEBUG_SEGMENT (0x0002) +#define LOGFS_DEBUG_JOURNAL (0x0004) +#define LOGFS_DEBUG_DIR (0x0008) +#define LOGFS_DEBUG_FILE (0x0010) +#define LOGFS_DEBUG_INODE (0x0020) +#define LOGFS_DEBUG_READWRITE (0x0040) +#define LOGFS_DEBUG_GC (0x0080) +#define LOGFS_DEBUG_GC_NOISY (0x0100) +#define LOGFS_DEBUG_ALIASES (0x0200) +#define LOGFS_DEBUG_BLOCKMOVE (0x0400) +#define LOGFS_DEBUG_ALL (0xffffffff) + +#define LOGFS_DEBUG (0x01) +/* + * To enable specific log messages, simply define LOGFS_DEBUG to match any + * or all of the above. + */ +#ifndef LOGFS_DEBUG +#define LOGFS_DEBUG (0) +#endif + +#define log_cond(cond, fmt, arg...) do { \ + if (cond) \ + printk(KERN_DEBUG fmt, ##arg); \ +} while (0) + +#define log_super(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_SUPER, fmt, ##arg) +#define log_segment(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_SEGMENT, fmt, ##arg) +#define log_journal(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_JOURNAL, fmt, ##arg) +#define log_dir(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_DIR, fmt, ##arg) +#define log_file(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_FILE, fmt, ##arg) +#define log_inode(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_INODE, fmt, ##arg) +#define log_readwrite(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_READWRITE, fmt, ##arg) +#define log_gc(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_GC, fmt, ##arg) +#define log_gc_noisy(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_GC_NOISY, fmt, ##arg) +#define log_aliases(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_ALIASES, fmt, ##arg) +#define log_blockmove(fmt, arg...) \ + log_cond(LOGFS_DEBUG & LOGFS_DEBUG_BLOCKMOVE, fmt, ##arg) + +#define PG_pre_locked PG_owner_priv_1 +#define PagePreLocked(page) test_bit(PG_pre_locked, &(page)->flags) +#define SetPagePreLocked(page) set_bit(PG_pre_locked, &(page)->flags) +#define ClearPagePreLocked(page) clear_bit(PG_pre_locked, &(page)->flags) + +/* FIXME: This should really be somewhere in the 64bit area. */ +#define LOGFS_LINK_MAX (1<<30) + +/* Read-only filesystem */ +#define LOGFS_SB_FLAG_RO 0x0001 +#define LOGFS_SB_FLAG_DIRTY 0x0002 +#define LOGFS_SB_FLAG_OBJ_ALIAS 0x0004 +#define LOGFS_SB_FLAG_SHUTDOWN 0x0008 + +/* Write Control Flags */ +#define WF_LOCK 0x01 /* take write lock */ +#define WF_WRITE 0x02 /* write block */ +#define WF_DELETE 0x04 /* delete old block */ + +typedef u8 __bitwise level_t; +typedef u8 __bitwise gc_level_t; + +#define LEVEL(level) ((__force level_t)(level)) +#define GC_LEVEL(gc_level) ((__force gc_level_t)(gc_level)) + +#define SUBLEVEL(level) ( (void)((level) == LEVEL(1)), \ + (__force level_t)((__force u8)(level) - 1) ) + +/** + * struct logfs_area - area management information + * + * @a_sb: the superblock this area belongs to + * @a_is_open: 1 if the area is currently open, else 0 + * @a_segno: segment number of area + * @a_written_bytes: number of bytes already written back + * @a_used_bytes: number of used bytes + * @a_ops: area operations (either journal or ostore) + * @a_erase_count: erase count + * @a_level: GC level + */ +struct logfs_area { /* a segment open for writing */ + struct super_block *a_sb; + int a_is_open; + u32 a_segno; + u32 a_written_bytes; + u32 a_used_bytes; + const struct logfs_area_ops *a_ops; + u32 a_erase_count; + gc_level_t a_level; +}; + +/** + * struct logfs_area_ops - area operations + * + * @get_free_segment: fill area->ofs with the offset of a free segment + * @get_erase_count: fill area->erase_count (needs area->ofs) + * @erase_segment: erase and setup segment + */ +struct logfs_area_ops { + void (*get_free_segment)(struct logfs_area *area); + void (*get_erase_count)(struct logfs_area *area); + int (*erase_segment)(struct logfs_area *area); +}; + +/** + * struct logfs_device_ops - device access operations + * + * @readpage: read one page (mm page) + * @writeseg: write one segment. may be a partial segment + * @erase: erase one segment + * @read: read from the device + * @erase: erase part of the device + */ +struct logfs_device_ops { + struct page *(*find_first_sb)(struct super_block *sb, u64 *ofs); + struct page *(*find_last_sb)(struct super_block *sb, u64 *ofs); + int (*write_sb)(struct super_block *sb, struct page *page); + int (*readpage)(void *_sb, struct page *page); + void (*writeseg)(struct super_block *sb, u64 ofs, size_t len); + int (*erase)(struct super_block *sb, loff_t ofs, size_t len, + int ensure_write); + void (*sync)(struct super_block *sb); + void (*put_device)(struct super_block *sb); +}; + +/** + * struct candidate_list - list of similar candidates + */ +struct candidate_list { + struct rb_root rb_tree; + int count; + int maxcount; + int sort_by_ec; +}; + +/** + * struct gc_candidate - "candidate" segment to be garbage collected next + * + * @list: list (either free of low) + * @segno: segment number + * @valid: number of valid bytes + * @erase_count: erase count of segment + * @dist: distance from tree root + * + * Candidates can be on two lists. The free list contains electees rather + * than candidates - segments that no longer contain any valid data. The + * low list contains candidates to be picked for GC. It should be kept + * short. It is not required to always pick a perfect candidate. In the + * worst case GC will have to move more data than absolutely necessary. + */ +struct gc_candidate { + struct rb_node rb_node; + struct candidate_list *list; + u32 segno; + u32 valid; + u32 erase_count; + u8 dist; +}; + +/** + * struct logfs_journal_entry - temporary structure used during journal scan + * + * @used: + * @version: normalized version + * @len: length + * @offset: offset + */ +struct logfs_journal_entry { + int used; + s16 version; + u16 len; + u16 datalen; + u64 offset; +}; + +enum transaction_state { + CREATE_1 = 1, + CREATE_2, + UNLINK_1, + UNLINK_2, + CROSS_RENAME_1, + CROSS_RENAME_2, + TARGET_RENAME_1, + TARGET_RENAME_2, + TARGET_RENAME_3 +}; + +/** + * struct logfs_transaction - essential fields to support atomic dirops + * + * @ino: target inode + * @dir: inode of directory containing dentry + * @pos: pos of dentry in directory + */ +struct logfs_transaction { + enum transaction_state state; + u64 ino; + u64 dir; + u64 pos; +}; + +/** + * struct logfs_shadow - old block in the shadow of a not-yet-committed new one + * @old_ofs: offset of old block on medium + * @new_ofs: offset of new block on medium + * @ino: inode number + * @bix: block index + * @old_len: size of old block, including header + * @new_len: size of new block, including header + * @level: block level + */ +struct logfs_shadow { + u64 old_ofs; + u64 new_ofs; + u64 ino; + u64 bix; + int old_len; + int new_len; + gc_level_t gc_level; +}; + +/** + * struct shadow_tree + * @new: shadows where old_ofs==0, indexed by new_ofs + * @old: shadows where old_ofs!=0, indexed by old_ofs + */ +struct shadow_tree { + struct btree_head64 new; + struct btree_head64 old; +}; + +struct object_alias_item { + struct list_head list; + __be64 val; + int child_no; +}; + +/** + * struct logfs_block - contains any block state + * @type: indirect block or inode + * @full: number of fully populated children + * @partial: number of partially populated children + * + * Most blocks are directly represented by page cache pages. But when a block + * becomes dirty, is part of a transaction, contains aliases or is otherwise + * special, a struct logfs_block is allocated to track the additional state. + * Inodes are very similar to indirect blocks, so they can also get one of + * these structures added when appropriate. + */ +#define BLOCK_INDIRECT 1 /* Indirect block */ +#define BLOCK_INODE 2 /* Inode */ +struct logfs_block_ops; +struct logfs_block { + struct list_head alias_list; + struct list_head item_list; + struct super_block *sb; + u64 ino; + u64 bix; + level_t level; + struct page *page; + struct inode *inode; + struct logfs_transaction *ta; + unsigned long alias_map[LOGFS_BLOCK_FACTOR / BITS_PER_LONG]; + struct logfs_block_ops *ops; + int full; + int partial; + int reserved_bytes; +}; + +typedef int write_alias_t(struct super_block *sb, u64 ino, u64 bix, + level_t level, int child_no, __be64 val); +struct logfs_block_ops { + void (*write_block)(struct logfs_block *block); + gc_level_t (*block_level)(struct logfs_block *block); + void (*free_block)(struct super_block *sb, struct logfs_block*block); + int (*write_alias)(struct super_block *sb, + struct logfs_block *block, + write_alias_t *write_one_alias); +}; + +struct logfs_super { + struct mtd_info *s_mtd; /* underlying device */ + struct block_device *s_bdev; /* underlying device */ + const struct logfs_device_ops *s_devops;/* device access */ + struct inode *s_master_inode; /* inode file */ + struct inode *s_segfile_inode; /* segment file */ + struct inode *s_mapping_inode; /* device mapping */ + atomic_t s_pending_writes; /* outstanting bios */ + long s_flags; + mempool_t *s_btree_pool; /* for btree nodes */ + mempool_t *s_alias_pool; /* aliases in segment.c */ + u64 s_feature_incompat; + u64 s_feature_ro_compat; + u64 s_feature_compat; + u64 s_feature_flags; + u64 s_sb_ofs[2]; + struct page *s_erase_page; /* for dev_bdev.c */ + /* alias.c fields */ + struct btree_head32 s_segment_alias; /* remapped segments */ + int s_no_object_aliases; + struct list_head s_object_alias; /* remapped objects */ + struct btree_head128 s_object_alias_tree; /* remapped objects */ + struct mutex s_object_alias_mutex; + /* dir.c fields */ + struct mutex s_dirop_mutex; /* for creat/unlink/rename */ + u64 s_victim_ino; /* used for atomic dir-ops */ + u64 s_rename_dir; /* source directory ino */ + u64 s_rename_pos; /* position of source dd */ + /* gc.c fields */ + long s_segsize; /* size of a segment */ + int s_segshift; /* log2 of segment size */ + long s_segmask; /* 1 << s_segshift - 1 */ + long s_no_segs; /* segments on device */ + long s_no_journal_segs; /* segments used for journal */ + long s_no_blocks; /* blocks per segment */ + long s_writesize; /* minimum write size */ + int s_writeshift; /* log2 of write size */ + u64 s_size; /* filesystem size */ + struct logfs_area *s_area[LOGFS_NO_AREAS]; /* open segment array */ + u64 s_gec; /* global erase count */ + u64 s_wl_gec_ostore; /* time of last wl event */ + u64 s_wl_gec_journal; /* time of last wl event */ + u64 s_sweeper; /* current sweeper pos */ + u8 s_ifile_levels; /* max level of ifile */ + u8 s_iblock_levels; /* max level of regular files */ + u8 s_data_levels; /* # of segments to leaf block*/ + u8 s_total_levels; /* sum of above three */ + struct btree_head32 s_cand_tree; /* all candidates */ + struct candidate_list s_free_list; /* 100% free segments */ + struct candidate_list s_reserve_list; /* Bad segment reserve */ + struct candidate_list s_low_list[LOGFS_NO_AREAS];/* good candidates */ + struct candidate_list s_ec_list; /* wear level candidates */ + struct btree_head32 s_reserved_segments;/* sb, journal, bad, etc. */ + /* inode.c fields */ + u64 s_last_ino; /* highest ino used */ + long s_inos_till_wrap; + u32 s_generation; /* i_generation for new files */ + struct list_head s_freeing_list; /* inodes being freed */ + /* journal.c fields */ + struct mutex s_journal_mutex; + void *s_je; /* journal entry to compress */ + void *s_compressed_je; /* block to write to journal */ + u32 s_journal_seg[LOGFS_JOURNAL_SEGS]; /* journal segments */ + u32 s_journal_ec[LOGFS_JOURNAL_SEGS]; /* journal erasecounts */ + u64 s_last_version; + struct logfs_area *s_journal_area; /* open journal segment */ + __be64 s_je_array[64]; + int s_no_je; + + int s_sum_index; /* for the 12 summaries */ + struct shadow_tree s_shadow_tree; + int s_je_fill; /* index of current je */ + /* readwrite.c fields */ + struct mutex s_write_mutex; + int s_lock_count; + mempool_t *s_block_pool; /* struct logfs_block pool */ + mempool_t *s_shadow_pool; /* struct logfs_shadow pool */ + /* + * Space accounting: + * - s_used_bytes specifies space used to store valid data objects. + * - s_dirty_used_bytes is space used to store non-committed data + * objects. Those objects have already been written themselves, + * but they don't become valid until all indirect blocks up to the + * journal have been written as well. + * - s_dirty_free_bytes is space used to store the old copy of a + * replaced object, as long as the replacement is non-committed. + * In other words, it is the amount of space freed when all dirty + * blocks are written back. + * - s_free_bytes is the amount of free space available for any + * purpose. + * - s_root_reserve is the amount of free space available only to + * the root user. Non-privileged users can no longer write once + * this watermark has been reached. + * - s_speed_reserve is space which remains unused to speed up + * garbage collection performance. + * - s_dirty_pages is the space reserved for currently dirty pages. + * It is a pessimistic estimate, so some/most will get freed on + * page writeback. + * + * s_used_bytes + s_free_bytes + s_speed_reserve = total usable size + */ + u64 s_free_bytes; + u64 s_used_bytes; + u64 s_dirty_free_bytes; + u64 s_dirty_used_bytes; + u64 s_root_reserve; + u64 s_speed_reserve; + u64 s_dirty_pages; + /* Bad block handling: + * - s_bad_seg_reserve is a number of segments usually kept + * free. When encountering bad blocks, the affected segment's data + * is _temporarily_ moved to a reserved segment. + * - s_bad_segments is the number of known bad segments. + */ + u32 s_bad_seg_reserve; + u32 s_bad_segments; +}; + +/** + * struct logfs_inode - in-memory inode + * + * @vfs_inode: struct inode + * @li_data: data pointers + * @li_used_bytes: number of used bytes + * @li_freeing_list: used to track inodes currently being freed + * @li_flags: inode flags + * @li_refcount: number of internal (GC-induced) references + */ +struct logfs_inode { + struct inode vfs_inode; + u64 li_data[LOGFS_EMBEDDED_FIELDS]; + u64 li_used_bytes; + struct list_head li_freeing_list; + struct logfs_block *li_block; + u32 li_flags; + u8 li_height; + int li_refcount; +}; + +#define journal_for_each(__i) for (__i = 0; __i < LOGFS_JOURNAL_SEGS; __i++) +#define for_each_area(__i) for (__i = 0; __i < LOGFS_NO_AREAS; __i++) +#define for_each_area_down(__i) for (__i = LOGFS_NO_AREAS - 1; __i >= 0; __i--) + +/* compr.c */ +int logfs_compress(void *in, void *out, size_t inlen, size_t outlen); +int logfs_uncompress(void *in, void *out, size_t inlen, size_t outlen); +int __init logfs_compr_init(void); +void logfs_compr_exit(void); + +/* dev_bdev.c */ +#ifdef CONFIG_BLOCK +int logfs_get_sb_bdev(struct file_system_type *type, int flags, + const char *devname, struct vfsmount *mnt); +#else +static inline int logfs_get_sb_bdev(struct file_system_type *type, int flags, + const char *devname, struct vfsmount *mnt) +{ + return -ENODEV; +} +#endif + +/* dev_mtd.c */ +#ifdef CONFIG_MTD +int logfs_get_sb_mtd(struct file_system_type *type, int flags, + int mtdnr, struct vfsmount *mnt); +#else +static inline int logfs_get_sb_mtd(struct file_system_type *type, int flags, + int mtdnr, struct vfsmount *mnt) +{ + return -ENODEV; +} +#endif + +/* dir.c */ +extern const struct inode_operations logfs_symlink_iops; +extern const struct inode_operations logfs_dir_iops; +extern const struct file_operations logfs_dir_fops; +int logfs_replay_journal(struct super_block *sb); + +/* file.c */ +extern const struct inode_operations logfs_reg_iops; +extern const struct file_operations logfs_reg_fops; +extern const struct address_space_operations logfs_reg_aops; +int logfs_readpage(struct file *file, struct page *page); +int logfs_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg); +int logfs_fsync(struct file *file, struct dentry *dentry, int datasync); + +/* gc.c */ +u32 get_best_cand(struct super_block *sb, struct candidate_list *list, u32 *ec); +void logfs_gc_pass(struct super_block *sb); +int logfs_check_areas(struct super_block *sb); +int logfs_init_gc(struct super_block *sb); +void logfs_cleanup_gc(struct super_block *sb); + +/* inode.c */ +extern const struct super_operations logfs_super_operations; +struct inode *logfs_iget(struct super_block *sb, ino_t ino); +struct inode *logfs_safe_iget(struct super_block *sb, ino_t ino, int *cookie); +void logfs_safe_iput(struct inode *inode, int cookie); +struct inode *logfs_new_inode(struct inode *dir, int mode); +struct inode *logfs_new_meta_inode(struct super_block *sb, u64 ino); +struct inode *logfs_read_meta_inode(struct super_block *sb, u64 ino); +int logfs_init_inode_cache(void); +void logfs_destroy_inode_cache(void); +void destroy_meta_inode(struct inode *inode); +void logfs_set_blocks(struct inode *inode, u64 no); +/* these logically belong into inode.c but actually reside in readwrite.c */ +int logfs_read_inode(struct inode *inode); +int __logfs_write_inode(struct inode *inode, long flags); +void logfs_delete_inode(struct inode *inode); +void logfs_clear_inode(struct inode *inode); + +/* journal.c */ +void logfs_write_anchor(struct super_block *sb); +int logfs_init_journal(struct super_block *sb); +void logfs_cleanup_journal(struct super_block *sb); +int write_alias_journal(struct super_block *sb, u64 ino, u64 bix, + level_t level, int child_no, __be64 val); +void do_logfs_journal_wl_pass(struct super_block *sb); + +/* readwrite.c */ +pgoff_t logfs_pack_index(u64 bix, level_t level); +void logfs_unpack_index(pgoff_t index, u64 *bix, level_t *level); +int logfs_inode_write(struct inode *inode, const void *buf, size_t count, + loff_t bix, long flags, struct shadow_tree *shadow_tree); +int logfs_readpage_nolock(struct page *page); +int logfs_write_buf(struct inode *inode, struct page *page, long flags); +int logfs_delete(struct inode *inode, pgoff_t index, + struct shadow_tree *shadow_tree); +int logfs_rewrite_block(struct inode *inode, u64 bix, u64 ofs, + gc_level_t gc_level, long flags); +int logfs_is_valid_block(struct super_block *sb, u64 ofs, u64 ino, u64 bix, + gc_level_t gc_level); +int logfs_truncate(struct inode *inode, u64 size); +u64 logfs_seek_hole(struct inode *inode, u64 bix); +u64 logfs_seek_data(struct inode *inode, u64 bix); +int logfs_open_segfile(struct super_block *sb); +int logfs_init_rw(struct super_block *sb); +void logfs_cleanup_rw(struct super_block *sb); +void logfs_add_transaction(struct inode *inode, struct logfs_transaction *ta); +void logfs_del_transaction(struct inode *inode, struct logfs_transaction *ta); +void logfs_write_block(struct logfs_block *block, long flags); +int logfs_write_obj_aliases_pagecache(struct super_block *sb); +void logfs_get_segment_entry(struct super_block *sb, u32 segno, + struct logfs_segment_entry *se); +void logfs_set_segment_used(struct super_block *sb, u64 ofs, int increment); +void logfs_set_segment_erased(struct super_block *sb, u32 segno, u32 ec, + gc_level_t gc_level); +void logfs_set_segment_reserved(struct super_block *sb, u32 segno); +void logfs_set_segment_unreserved(struct super_block *sb, u32 segno, u32 ec); +struct logfs_block *__alloc_block(struct super_block *sb, + u64 ino, u64 bix, level_t level); +void __free_block(struct super_block *sb, struct logfs_block *block); +void btree_write_block(struct logfs_block *block); +void initialize_block_counters(struct page *page, struct logfs_block *block, + __be64 *array, int page_is_empty); +int logfs_exist_block(struct inode *inode, u64 bix); +int get_page_reserve(struct inode *inode, struct page *page); +extern struct logfs_block_ops indirect_block_ops; + +/* segment.c */ +int logfs_erase_segment(struct super_block *sb, u32 ofs, int ensure_erase); +int wbuf_read(struct super_block *sb, u64 ofs, size_t len, void *buf); +int logfs_segment_read(struct inode *inode, struct page *page, u64 ofs, u64 bix, + level_t level); +int logfs_segment_write(struct inode *inode, struct page *page, + struct logfs_shadow *shadow); +int logfs_segment_delete(struct inode *inode, struct logfs_shadow *shadow); +int logfs_load_object_aliases(struct super_block *sb, + struct logfs_obj_alias *oa, int count); +void move_page_to_btree(struct page *page); +int logfs_init_mapping(struct super_block *sb); +void logfs_sync_area(struct logfs_area *area); +void logfs_sync_segments(struct super_block *sb); + +/* area handling */ +int logfs_init_areas(struct super_block *sb); +void logfs_cleanup_areas(struct super_block *sb); +int logfs_open_area(struct logfs_area *area, size_t bytes); +void __logfs_buf_write(struct logfs_area *area, u64 ofs, void *buf, size_t len, + int use_filler); + +static inline void logfs_buf_write(struct logfs_area *area, u64 ofs, + void *buf, size_t len) +{ + __logfs_buf_write(area, ofs, buf, len, 0); +} + +static inline void logfs_buf_recover(struct logfs_area *area, u64 ofs, + void *buf, size_t len) +{ + __logfs_buf_write(area, ofs, buf, len, 1); +} + +/* super.c */ +struct page *emergency_read_begin(struct address_space *mapping, pgoff_t index); +void emergency_read_end(struct page *page); +void logfs_crash_dump(struct super_block *sb); +void *memchr_inv(const void *s, int c, size_t n); +int logfs_statfs(struct dentry *dentry, struct kstatfs *stats); +int logfs_get_sb_device(struct file_system_type *type, int flags, + struct mtd_info *mtd, struct block_device *bdev, + const struct logfs_device_ops *devops, struct vfsmount *mnt); +int logfs_check_ds(struct logfs_disk_super *ds); +int logfs_write_sb(struct super_block *sb); + +static inline struct logfs_super *logfs_super(struct super_block *sb) +{ + return sb->s_fs_info; +} + +static inline struct logfs_inode *logfs_inode(struct inode *inode) +{ + return container_of(inode, struct logfs_inode, vfs_inode); +} + +static inline void logfs_set_ro(struct super_block *sb) +{ + logfs_super(sb)->s_flags |= LOGFS_SB_FLAG_RO; +} + +#define LOGFS_BUG(sb) do { \ + struct super_block *__sb = sb; \ + logfs_crash_dump(__sb); \ + logfs_super(__sb)->s_flags |= LOGFS_SB_FLAG_RO; \ + BUG(); \ +} while (0) + +#define LOGFS_BUG_ON(condition, sb) \ + do { if (unlikely(condition)) LOGFS_BUG((sb)); } while (0) + +static inline __be32 logfs_crc32(void *data, size_t len, size_t skip) +{ + return cpu_to_be32(crc32(~0, data+skip, len-skip)); +} + +static inline u8 logfs_type(struct inode *inode) +{ + return (inode->i_mode >> 12) & 15; +} + +static inline pgoff_t logfs_index(struct super_block *sb, u64 pos) +{ + return pos >> sb->s_blocksize_bits; +} + +static inline u64 dev_ofs(struct super_block *sb, u32 segno, u32 ofs) +{ + return ((u64)segno << logfs_super(sb)->s_segshift) + ofs; +} + +static inline u32 seg_no(struct super_block *sb, u64 ofs) +{ + return ofs >> logfs_super(sb)->s_segshift; +} + +static inline u32 seg_ofs(struct super_block *sb, u64 ofs) +{ + return ofs & logfs_super(sb)->s_segmask; +} + +static inline u64 seg_align(struct super_block *sb, u64 ofs) +{ + return ofs & ~logfs_super(sb)->s_segmask; +} + +static inline struct logfs_block *logfs_block(struct page *page) +{ + return (void *)page->private; +} + +static inline level_t shrink_level(gc_level_t __level) +{ + u8 level = (__force u8)__level; + + if (level >= LOGFS_MAX_LEVELS) + level -= LOGFS_MAX_LEVELS; + return (__force level_t)level; +} + +static inline gc_level_t expand_level(u64 ino, level_t __level) +{ + u8 level = (__force u8)__level; + + if (ino == LOGFS_INO_MASTER) { + /* ifile has seperate areas */ + level += LOGFS_MAX_LEVELS; + } + return (__force gc_level_t)level; +} + +static inline int logfs_block_shift(struct super_block *sb, level_t level) +{ + level = shrink_level((__force gc_level_t)level); + return (__force int)level * (sb->s_blocksize_bits - 3); +} + +static inline u64 logfs_block_mask(struct super_block *sb, level_t level) +{ + return ~0ull << logfs_block_shift(sb, level); +} + +static inline struct logfs_area *get_area(struct super_block *sb, + gc_level_t gc_level) +{ + return logfs_super(sb)->s_area[(__force u8)gc_level]; +} + +#endif |