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 spinlock_t lock; 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 /* bytenr on disk */ 37 u64 bytenr; 38 u32 sum; 39 }; 40 41 struct btrfs_ordered_sum { 42 /* bytenr is the start of this extent on disk */ 43 u64 bytenr; 44 45 /* 46 * this is the length in bytes covered by the sums array below. 47 */ 48 unsigned long len; 49 struct list_head list; 50 /* last field is a variable length array of btrfs_sector_sums */ 51 struct btrfs_sector_sum sums[]; 52 }; 53 54 /* 55 * bits for the flags field: 56 * 57 * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written. 58 * It is used to make sure metadata is inserted into the tree only once 59 * per extent. 60 * 61 * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the 62 * rbtree, just before waking any waiters. It is used to indicate the 63 * IO is done and any metadata is inserted into the tree. 64 */ 65 #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */ 66 67 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */ 68 69 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */ 70 71 #define BTRFS_ORDERED_COMPRESSED 3 /* writing a compressed extent */ 72 73 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */ 74 75 #define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */ 76 77 struct btrfs_ordered_extent { 78 /* logical offset in the file */ 79 u64 file_offset; 80 81 /* disk byte number */ 82 u64 start; 83 84 /* ram length of the extent in bytes */ 85 u64 len; 86 87 /* extent length on disk */ 88 u64 disk_len; 89 90 /* number of bytes that still need writing */ 91 u64 bytes_left; 92 93 /* flags (described above) */ 94 unsigned long flags; 95 96 /* reference count */ 97 atomic_t refs; 98 99 /* the inode we belong to */ 100 struct inode *inode; 101 102 /* list of checksums for insertion when the extent io is done */ 103 struct list_head list; 104 105 /* used to wait for the BTRFS_ORDERED_COMPLETE bit */ 106 wait_queue_head_t wait; 107 108 /* our friendly rbtree entry */ 109 struct rb_node rb_node; 110 111 /* a per root list of all the pending ordered extents */ 112 struct list_head root_extent_list; 113 }; 114 115 116 /* 117 * calculates the total size you need to allocate for an ordered sum 118 * structure spanning 'bytes' in the file 119 */ 120 static inline int btrfs_ordered_sum_size(struct btrfs_root *root, 121 unsigned long bytes) 122 { 123 unsigned long num_sectors = (bytes + root->sectorsize - 1) / 124 root->sectorsize; 125 num_sectors++; 126 return sizeof(struct btrfs_ordered_sum) + 127 num_sectors * sizeof(struct btrfs_sector_sum); 128 } 129 130 static inline void 131 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t) 132 { 133 spin_lock_init(&t->lock); 134 t->tree = RB_ROOT; 135 t->last = NULL; 136 } 137 138 int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry); 139 int btrfs_remove_ordered_extent(struct inode *inode, 140 struct btrfs_ordered_extent *entry); 141 int btrfs_dec_test_ordered_pending(struct inode *inode, 142 struct btrfs_ordered_extent **cached, 143 u64 file_offset, u64 io_size); 144 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, 145 u64 start, u64 len, u64 disk_len, int type); 146 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset, 147 u64 start, u64 len, u64 disk_len, int type); 148 int btrfs_add_ordered_sum(struct inode *inode, 149 struct btrfs_ordered_extent *entry, 150 struct btrfs_ordered_sum *sum); 151 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode, 152 u64 file_offset); 153 void btrfs_start_ordered_extent(struct inode *inode, 154 struct btrfs_ordered_extent *entry, int wait); 155 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len); 156 struct btrfs_ordered_extent * 157 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset); 158 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode, 159 u64 file_offset, 160 u64 len); 161 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset, 162 struct btrfs_ordered_extent *ordered); 163 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum); 164 int btrfs_run_ordered_operations(struct btrfs_root *root, int wait); 165 int btrfs_add_ordered_operation(struct btrfs_trans_handle *trans, 166 struct btrfs_root *root, 167 struct inode *inode); 168 int btrfs_wait_ordered_extents(struct btrfs_root *root, 169 int nocow_only, int delay_iput); 170 #endif 171