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_VOLUMES_ 20 #define __BTRFS_VOLUMES_ 21 22 #include <linux/bio.h> 23 #include <linux/sort.h> 24 #include "async-thread.h" 25 26 #define BTRFS_STRIPE_LEN (64 * 1024) 27 28 struct buffer_head; 29 struct btrfs_pending_bios { 30 struct bio *head; 31 struct bio *tail; 32 }; 33 34 struct btrfs_device { 35 struct list_head dev_list; 36 struct list_head dev_alloc_list; 37 struct btrfs_fs_devices *fs_devices; 38 struct btrfs_root *dev_root; 39 40 /* regular prio bios */ 41 struct btrfs_pending_bios pending_bios; 42 /* WRITE_SYNC bios */ 43 struct btrfs_pending_bios pending_sync_bios; 44 45 int running_pending; 46 u64 generation; 47 48 int writeable; 49 int in_fs_metadata; 50 int missing; 51 52 spinlock_t io_lock; 53 54 struct block_device *bdev; 55 56 /* the mode sent to blkdev_get */ 57 fmode_t mode; 58 59 char *name; 60 61 /* the internal btrfs device id */ 62 u64 devid; 63 64 /* size of the device */ 65 u64 total_bytes; 66 67 /* size of the disk */ 68 u64 disk_total_bytes; 69 70 /* bytes used */ 71 u64 bytes_used; 72 73 /* optimal io alignment for this device */ 74 u32 io_align; 75 76 /* optimal io width for this device */ 77 u32 io_width; 78 79 /* minimal io size for this device */ 80 u32 sector_size; 81 82 /* type and info about this device */ 83 u64 type; 84 85 /* physical drive uuid (or lvm uuid) */ 86 u8 uuid[BTRFS_UUID_SIZE]; 87 88 struct btrfs_work work; 89 }; 90 91 struct btrfs_fs_devices { 92 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ 93 94 /* the device with this id has the most recent copy of the super */ 95 u64 latest_devid; 96 u64 latest_trans; 97 u64 num_devices; 98 u64 open_devices; 99 u64 rw_devices; 100 u64 missing_devices; 101 u64 total_rw_bytes; 102 struct block_device *latest_bdev; 103 104 /* all of the devices in the FS, protected by a mutex 105 * so we can safely walk it to write out the supers without 106 * worrying about add/remove by the multi-device code 107 */ 108 struct mutex device_list_mutex; 109 struct list_head devices; 110 111 /* devices not currently being allocated */ 112 struct list_head alloc_list; 113 struct list_head list; 114 115 struct btrfs_fs_devices *seed; 116 int seeding; 117 118 int opened; 119 120 /* set when we find or add a device that doesn't have the 121 * nonrot flag set 122 */ 123 int rotating; 124 }; 125 126 struct btrfs_bio_stripe { 127 struct btrfs_device *dev; 128 u64 physical; 129 }; 130 131 struct btrfs_multi_bio { 132 atomic_t stripes_pending; 133 bio_end_io_t *end_io; 134 struct bio *orig_bio; 135 void *private; 136 atomic_t error; 137 int max_errors; 138 int num_stripes; 139 struct btrfs_bio_stripe stripes[]; 140 }; 141 142 struct btrfs_device_info { 143 struct btrfs_device *dev; 144 u64 dev_offset; 145 u64 max_avail; 146 }; 147 148 /* Used to sort the devices by max_avail(descending sort) */ 149 int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2); 150 151 /* 152 * sort the devices by max_avail, in which max free extent size of each device 153 * is stored.(Descending Sort) 154 */ 155 static inline void btrfs_descending_sort_devices( 156 struct btrfs_device_info *devices, 157 size_t nr_devices) 158 { 159 sort(devices, nr_devices, sizeof(struct btrfs_device_info), 160 btrfs_cmp_device_free_bytes, NULL); 161 } 162 163 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 164 u64 end, u64 *length); 165 166 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \ 167 (sizeof(struct btrfs_bio_stripe) * (n))) 168 169 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 170 struct btrfs_device *device, 171 u64 chunk_tree, u64 chunk_objectid, 172 u64 chunk_offset, u64 start, u64 num_bytes); 173 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, 174 u64 logical, u64 *length, 175 struct btrfs_multi_bio **multi_ret, int mirror_num); 176 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 177 u64 chunk_start, u64 physical, u64 devid, 178 u64 **logical, int *naddrs, int *stripe_len); 179 int btrfs_read_sys_array(struct btrfs_root *root); 180 int btrfs_read_chunk_tree(struct btrfs_root *root); 181 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 182 struct btrfs_root *extent_root, u64 type); 183 void btrfs_mapping_init(struct btrfs_mapping_tree *tree); 184 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree); 185 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 186 int mirror_num, int async_submit); 187 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf); 188 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 189 fmode_t flags, void *holder); 190 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 191 struct btrfs_fs_devices **fs_devices_ret); 192 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices); 193 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices); 194 int btrfs_add_device(struct btrfs_trans_handle *trans, 195 struct btrfs_root *root, 196 struct btrfs_device *device); 197 int btrfs_rm_device(struct btrfs_root *root, char *device_path); 198 int btrfs_cleanup_fs_uuids(void); 199 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len); 200 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree, 201 u64 logical, struct page *page); 202 int btrfs_grow_device(struct btrfs_trans_handle *trans, 203 struct btrfs_device *device, u64 new_size); 204 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid, 205 u8 *uuid, u8 *fsid); 206 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size); 207 int btrfs_init_new_device(struct btrfs_root *root, char *path); 208 int btrfs_balance(struct btrfs_root *dev_root); 209 void btrfs_unlock_volumes(void); 210 void btrfs_lock_volumes(void); 211 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset); 212 int find_free_dev_extent(struct btrfs_trans_handle *trans, 213 struct btrfs_device *device, u64 num_bytes, 214 u64 *start, u64 *max_avail); 215 #endif 216