LXR linux/fs/btrfs/ordered-data.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
   4 */
   5
   6#ifndef BTRFS_ORDERED_DATA_H
   7#define BTRFS_ORDERED_DATA_H
   8
   9/* one of these per inode */
  10struct btrfs_ordered_inode_tree {
  11        spinlock_t lock;
  12        struct rb_root tree;
  13        struct rb_node *last;
  14};
  15
  16struct btrfs_ordered_sum {
  17        /* bytenr is the start of this extent on disk */
  18        u64 bytenr;
  19
  20        /*
  21         * this is the length in bytes covered by the sums array below.
  22         */
  23        int len;
  24        struct list_head list;
  25        /* last field is a variable length array of csums */
  26        u32 sums[];
  27};
  28
  29/*
  30 * bits for the flags field:
  31 *
  32 * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
  33 * It is used to make sure metadata is inserted into the tree only once
  34 * per extent.
  35 *
  36 * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
  37 * rbtree, just before waking any waiters.  It is used to indicate the
  38 * IO is done and any metadata is inserted into the tree.
  39 */
  40#define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
  41
  42#define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
  43
  44#define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
  45
  46#define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
  47
  48#define BTRFS_ORDERED_PREALLOC 4 /* set when writing to preallocated extent */
  49
  50#define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
  51
  52#define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
  53
  54#define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates whether this ordered extent
  55                                       * has done its due diligence in updating
  56                                       * the isize. */
  57#define BTRFS_ORDERED_TRUNCATED 8 /* Set when we have to truncate an extent */
  58
  59#define BTRFS_ORDERED_PENDING 9 /* We are waiting for this ordered extent to
  60                                  * complete in the current transaction. */
  61#define BTRFS_ORDERED_REGULAR 10 /* Regular IO for COW */
  62
  63struct btrfs_ordered_extent {
  64        /* logical offset in the file */
  65        u64 file_offset;
  66
  67        /* disk byte number */
  68        u64 start;
  69
  70        /* ram length of the extent in bytes */
  71        u64 len;
  72
  73        /* extent length on disk */
  74        u64 disk_len;
  75
  76        /* number of bytes that still need writing */
  77        u64 bytes_left;
  78
  79        /*
  80         * the end of the ordered extent which is behind it but
  81         * didn't update disk_i_size. Please see the comment of
  82         * btrfs_ordered_update_i_size();
  83         */
  84        u64 outstanding_isize;
  85
  86        /*
  87         * If we get truncated we need to adjust the file extent we enter for
  88         * this ordered extent so that we do not expose stale data.
  89         */
  90        u64 truncated_len;
  91
  92        /* flags (described above) */
  93        unsigned long flags;
  94
  95        /* compression algorithm */
  96        int compress_type;
  97
  98        /* reference count */
  99        refcount_t refs;
 100
 101        /* the inode we belong to */
 102        struct inode *inode;
 103
 104        /* list of checksums for insertion when the extent io is done */
 105        struct list_head list;
 106
 107        /* If we need to wait on this to be done */
 108        struct list_head log_list;
 109
 110        /* If the transaction needs to wait on this ordered extent */
 111        struct list_head trans_list;
 112
 113        /* used to wait for the BTRFS_ORDERED_COMPLETE bit */
 114        wait_queue_head_t wait;
 115
 116        /* our friendly rbtree entry */
 117        struct rb_node rb_node;
 118
 119        /* a per root list of all the pending ordered extents */
 120        struct list_head root_extent_list;
 121
 122        struct btrfs_work work;
 123
 124        struct completion completion;
 125        struct btrfs_work flush_work;
 126        struct list_head work_list;
 127};
 128
 129/*
 130 * calculates the total size you need to allocate for an ordered sum
 131 * structure spanning 'bytes' in the file
 132 */
 133static inline int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info,
 134                                         unsigned long bytes)
 135{
 136        int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
 137        int csum_size = btrfs_super_csum_size(fs_info->super_copy);
 138
 139        return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
 140}
 141
 142static inline void
 143btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
 144{
 145        spin_lock_init(&t->lock);
 146        t->tree = RB_ROOT;
 147        t->last = NULL;
 148}
 149
 150void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
 151void btrfs_remove_ordered_extent(struct inode *inode,
 152                                struct btrfs_ordered_extent *entry);
 153int btrfs_dec_test_ordered_pending(struct inode *inode,
 154                                   struct btrfs_ordered_extent **cached,
 155                                   u64 file_offset, u64 io_size, int uptodate);
 156int btrfs_dec_test_first_ordered_pending(struct inode *inode,
 157                                   struct btrfs_ordered_extent **cached,
 158                                   u64 *file_offset, u64 io_size,
 159                                   int uptodate);
 160int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 161                             u64 start, u64 len, u64 disk_len, int type);
 162int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
 163                                 u64 start, u64 len, u64 disk_len, int type);
 164int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
 165                                      u64 start, u64 len, u64 disk_len,
 166                                      int type, int compress_type);
 167void btrfs_add_ordered_sum(struct inode *inode,
 168                           struct btrfs_ordered_extent *entry,
 169                           struct btrfs_ordered_sum *sum);
 170struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
 171                                                         u64 file_offset);
 172void btrfs_start_ordered_extent(struct inode *inode,
 173                                struct btrfs_ordered_extent *entry, int wait);
 174int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
 175struct btrfs_ordered_extent *
 176btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
 177struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 178                struct btrfs_inode *inode,
 179                u64 file_offset,
 180                u64 len);
 181int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 182                                struct btrfs_ordered_extent *ordered);
 183int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 184                           u32 *sum, int len);
 185u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 186                               const u64 range_start, const u64 range_len);
 187u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 188                              const u64 range_start, const u64 range_len);
 189int __init ordered_data_init(void);
 190void __cold ordered_data_exit(void);
 191
 192#endif
 193