fs/nilfs2/mdt.h

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