LXR linux/fs/nilfs2/mdt.h

   1/* SPDX-License-Identifier: GPL-2.0+ */
   2/*
   3 * mdt.h - NILFS meta data file prototype and definitions
   4 *
   5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   6 *
   7 * Written by Ryusuke Konishi.
   8 */
   9
  10#ifndef _NILFS_MDT_H
  11#define _NILFS_MDT_H
  12
  13#include <linux/buffer_head.h>
  14#include <linux/blockgroup_lock.h>
  15#include "nilfs.h"
  16#include "page.h"
  17
  18/**
  19 * struct nilfs_shadow_map - shadow mapping of meta data file
  20 * @bmap_store: shadow copy of bmap state
  21 * @frozen_data: shadowed dirty data pages
  22 * @frozen_btnodes: shadowed dirty b-tree nodes' pages
  23 * @frozen_buffers: list of frozen buffers
  24 */
  25struct nilfs_shadow_map {
  26        struct nilfs_bmap_store bmap_store;
  27        struct address_space frozen_data;
  28        struct address_space frozen_btnodes;
  29        struct list_head frozen_buffers;
  30};
  31
  32/**
  33 * struct nilfs_mdt_info - on-memory private data of meta data files
  34 * @mi_sem: reader/writer semaphore for meta data operations
  35 * @mi_bgl: per-blockgroup locking
  36 * @mi_entry_size: size of an entry
  37 * @mi_first_entry_offset: offset to the first entry
  38 * @mi_entries_per_block: number of entries in a block
  39 * @mi_palloc_cache: persistent object allocator cache
  40 * @mi_shadow: shadow of bmap and page caches
  41 * @mi_blocks_per_group: number of blocks in a group
  42 * @mi_blocks_per_desc_block: number of blocks per descriptor block
  43 */
  44struct nilfs_mdt_info {
  45        struct rw_semaphore     mi_sem;
  46        struct blockgroup_lock *mi_bgl;
  47        unsigned int            mi_entry_size;
  48        unsigned int            mi_first_entry_offset;
  49        unsigned long           mi_entries_per_block;
  50        struct nilfs_palloc_cache *mi_palloc_cache;
  51        struct nilfs_shadow_map *mi_shadow;
  52        unsigned long           mi_blocks_per_group;
  53        unsigned long           mi_blocks_per_desc_block;
  54};
  55
  56static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode)
  57{
  58        return inode->i_private;
  59}
  60
  61static inline int nilfs_is_metadata_file_inode(const struct inode *inode)
  62{
  63        return inode->i_private != NULL;
  64}
  65
  66/* Default GFP flags using highmem */
  67#define NILFS_MDT_GFP      (__GFP_RECLAIM | __GFP_IO | __GFP_HIGHMEM)
  68
  69int nilfs_mdt_get_block(struct inode *, unsigned long, int,
  70                        void (*init_block)(struct inode *,
  71                                           struct buffer_head *, void *),
  72                        struct buffer_head **);
  73int nilfs_mdt_find_block(struct inode *inode, unsigned long start,
  74                         unsigned long end, unsigned long *blkoff,
  75                         struct buffer_head **out_bh);
  76int nilfs_mdt_delete_block(struct inode *, unsigned long);
  77int nilfs_mdt_forget_block(struct inode *, unsigned long);
  78int nilfs_mdt_fetch_dirty(struct inode *);
  79
  80int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz);
  81void nilfs_mdt_clear(struct inode *inode);
  82void nilfs_mdt_destroy(struct inode *inode);
  83
  84void nilfs_mdt_set_entry_size(struct inode *, unsigned int, unsigned int);
  85
  86int nilfs_mdt_setup_shadow_map(struct inode *inode,
  87                               struct nilfs_shadow_map *shadow);
  88int nilfs_mdt_save_to_shadow_map(struct inode *inode);
  89void nilfs_mdt_restore_from_shadow_map(struct inode *inode);
  90void nilfs_mdt_clear_shadow_map(struct inode *inode);
  91int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh);
  92struct buffer_head *nilfs_mdt_get_frozen_buffer(struct inode *inode,
  93                                                struct buffer_head *bh);
  94
  95static inline void nilfs_mdt_mark_dirty(struct inode *inode)
  96{
  97        if (!test_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state))
  98                set_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
  99}
 100
 101static inline void nilfs_mdt_clear_dirty(struct inode *inode)
 102{
 103        clear_bit(NILFS_I_DIRTY, &NILFS_I(inode)->i_state);
 104}
 105
 106static inline __u64 nilfs_mdt_cno(struct inode *inode)
 107{
 108        return ((struct the_nilfs *)inode->i_sb->s_fs_info)->ns_cno;
 109}
 110
 111static inline spinlock_t *
 112nilfs_mdt_bgl_lock(struct inode *inode, unsigned int block_group)
 113{
 114        return bgl_lock_ptr(NILFS_MDT(inode)->mi_bgl, block_group);
 115}
 116
 117#endif /* _NILFS_MDT_H */
 118