fs/nilfs2/page.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * page.h - buffer/page management specific to NILFS
   4  *
   5  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   6  *
   7  * Written by Ryusuke Konishi and Seiji Kihara.
   8  */
   9
  10 #ifndef _NILFS_PAGE_H
  11 #define _NILFS_PAGE_H
  12
  13 #include <linux/buffer_head.h>
  14 #include "nilfs.h"
  15
  16 /*
  17  * Extended buffer state bits
  18  */
  19 enum {
  20         BH_NILFS_Allocated = BH_PrivateStart,
  21         BH_NILFS_Node,
  22         BH_NILFS_Volatile,
  23         BH_NILFS_Checked,
  24         BH_NILFS_Redirected,
  25 };
  26
  27 BUFFER_FNS(NILFS_Node, nilfs_node)              /* nilfs node buffers */
  28 BUFFER_FNS(NILFS_Volatile, nilfs_volatile)
  29 BUFFER_FNS(NILFS_Checked, nilfs_checked)        /* buffer is verified */
  30 BUFFER_FNS(NILFS_Redirected, nilfs_redirected)  /* redirected to a copy */
  31
  32
  33 int __nilfs_clear_page_dirty(struct page *);
  34
  35 struct buffer_head *nilfs_grab_buffer(struct inode *, struct address_space *,
  36                                       unsigned long, unsigned long);
  37 void nilfs_forget_buffer(struct buffer_head *);
  38 void nilfs_copy_buffer(struct buffer_head *, struct buffer_head *);
  39 int nilfs_page_buffers_clean(struct page *);
  40 void nilfs_page_bug(struct page *);
  41
  42 int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
  43 void nilfs_copy_back_pages(struct address_space *, struct address_space *);
  44 void nilfs_clear_dirty_page(struct page *, bool);
  45 void nilfs_clear_dirty_pages(struct address_space *, bool);
  46 void nilfs_mapping_init(struct address_space *mapping, struct inode *inode);
  47 unsigned int nilfs_page_count_clean_buffers(struct page *, unsigned int,
  48                                             unsigned int);
  49 unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
  50                                             sector_t start_blk,
  51                                             sector_t *blkoff);
  52
  53 #define NILFS_PAGE_BUG(page, m, a...) \
  54         do { nilfs_page_bug(page); BUG(); } while (0)
  55
  56 static inline struct buffer_head *
  57 nilfs_page_get_nth_block(struct page *page, unsigned int count)
  58 {
  59         struct buffer_head *bh = page_buffers(page);
  60
  61         while (count-- > 0)
  62                 bh = bh->b_this_page;
  63         get_bh(bh);
  64         return bh;
  65 }
  66
  67 #endif /* _NILFS_PAGE_H */