| 1 | /* |
| 2 | * Copyright (C) 2007 Oracle. All rights reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public |
| 6 | * License v2 as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 11 | * General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public |
| 14 | * License along with this program; if not, write to the |
| 15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 16 | * Boston, MA 021110-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #ifndef __BTRFS_ORDERED_DATA__ |
| 20 | #define __BTRFS_ORDERED_DATA__ |
| 21 | |
| 22 | /* one of these per inode */ |
| 23 | struct btrfs_ordered_inode_tree { |
| 24 | struct mutex mutex; |
| 25 | struct rb_root tree; |
| 26 | struct rb_node *last; |
| 27 | }; |
| 28 | |
| 29 | /* |
| 30 | * these are used to collect checksums done just before bios submission. |
| 31 | * They are attached via a list into the ordered extent, and |
| 32 | * checksum items are inserted into the tree after all the blocks in |
| 33 | * the ordered extent are on disk |
| 34 | */ |
| 35 | struct btrfs_sector_sum { |
| 36 | u64 offset; |
| 37 | u32 sum; |
| 38 | }; |
| 39 | |
| 40 | struct btrfs_ordered_sum { |
| 41 | u64 file_offset; |
| 42 | /* |
| 43 | * this is the length in bytes covered by the sums array below. |
| 44 | * But, the sums array may not be contiguous in the file. |
| 45 | */ |
| 46 | unsigned long len; |
| 47 | struct list_head list; |
| 48 | /* last field is a variable length array of btrfs_sector_sums */ |
| 49 | struct btrfs_sector_sum sums[]; |
| 50 | }; |
| 51 | |
| 52 | /* |
| 53 | * bits for the flags field: |
| 54 | * |
| 55 | * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written. |
| 56 | * It is used to make sure metadata is inserted into the tree only once |
| 57 | * per extent. |
| 58 | * |
| 59 | * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the |
| 60 | * rbtree, just before waking any waiters. It is used to indicate the |
| 61 | * IO is done and any metadata is inserted into the tree. |
| 62 | */ |
| 63 | #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */ |
| 64 | |
| 65 | #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */ |
| 66 | |
| 67 | #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */ |
| 68 | |
| 69 | #define BTRFS_ORDERED_COMPRESSED 3 /* writing a compressed extent */ |
| 70 | |
| 71 | #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */ |
| 72 | |
| 73 | struct btrfs_ordered_extent { |
| 74 | /* logical offset in the file */ |
| 75 | u64 file_offset; |
| 76 | |
| 77 | /* disk byte number */ |
| 78 | u64 start; |
| 79 | |
| 80 | /* ram length of the extent in bytes */ |
| 81 | u64 len; |
| 82 | |
| 83 | /* extent length on disk */ |
| 84 | u64 disk_len; |
| 85 | |
| 86 | /* flags (described above) */ |
| 87 | unsigned long flags; |
| 88 | |
| 89 | /* reference count */ |
| 90 | atomic_t refs; |
| 91 | |
| 92 | /* the inode we belong to */ |
| 93 | struct inode *inode; |
| 94 | |
| 95 | /* list of checksums for insertion when the extent io is done */ |
| 96 | struct list_head list; |
| 97 | |
| 98 | /* used to wait for the BTRFS_ORDERED_COMPLETE bit */ |
| 99 | wait_queue_head_t wait; |
| 100 | |
| 101 | /* our friendly rbtree entry */ |
| 102 | struct rb_node rb_node; |
| 103 | |
| 104 | /* a per root list of all the pending ordered extents */ |
| 105 | struct list_head root_extent_list; |
| 106 | }; |
| 107 | |
| 108 | |
| 109 | /* |
| 110 | * calculates the total size you need to allocate for an ordered sum |
| 111 | * structure spanning 'bytes' in the file |
| 112 | */ |
| 113 | static inline int btrfs_ordered_sum_size(struct btrfs_root *root, |
| 114 | unsigned long bytes) |
| 115 | { |
| 116 | unsigned long num_sectors = (bytes + root->sectorsize - 1) / |
| 117 | root->sectorsize; |
| 118 | num_sectors++; |
| 119 | return sizeof(struct btrfs_ordered_sum) + |
| 120 | num_sectors * sizeof(struct btrfs_sector_sum); |
| 121 | } |
| 122 | |
| 123 | static inline void |
| 124 | btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t) |
| 125 | { |
| 126 | mutex_init(&t->mutex); |
| 127 | t->tree.rb_node = NULL; |
| 128 | t->last = NULL; |
| 129 | } |
| 130 | |
| 131 | int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry); |
| 132 | int btrfs_remove_ordered_extent(struct inode *inode, |
| 133 | struct btrfs_ordered_extent *entry); |
| 134 | int btrfs_dec_test_ordered_pending(struct inode *inode, |
| 135 | u64 file_offset, u64 io_size); |
| 136 | int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, |
| 137 | u64 start, u64 len, u64 disk_len, int tyep); |
| 138 | int btrfs_add_ordered_sum(struct inode *inode, |
| 139 | struct btrfs_ordered_extent *entry, |
| 140 | struct btrfs_ordered_sum *sum); |
| 141 | struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode, |
| 142 | u64 file_offset); |
| 143 | void btrfs_start_ordered_extent(struct inode *inode, |
| 144 | struct btrfs_ordered_extent *entry, int wait); |
| 145 | int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len); |
| 146 | struct btrfs_ordered_extent * |
| 147 | btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset); |
| 148 | int btrfs_ordered_update_i_size(struct inode *inode, |
| 149 | struct btrfs_ordered_extent *ordered); |
| 150 | int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u32 *sum); |
| 151 | int btrfs_wait_on_page_writeback_range(struct address_space *mapping, |
| 152 | pgoff_t start, pgoff_t end); |
| 153 | int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start, |
| 154 | loff_t end, int sync_mode); |
| 155 | int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only); |
| 156 | #endif |