fs/btrfs/volumes.h

   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
  24 struct buffer_head;
  25 struct btrfs_device {
  26         struct list_head dev_list;
  27         struct list_head dev_alloc_list;
  28         struct btrfs_root *dev_root;
  29         struct buffer_head *pending_io;
  30
  31         int barriers;
  32
  33         spinlock_t io_lock;
  34
  35         struct block_device *bdev;
  36
  37         u64 total_ios;
  38
  39         char *name;
  40
  41         /* the internal btrfs device id */
  42         u64 devid;
  43
  44         /* size of the device */
  45         u64 total_bytes;
  46
  47         /* bytes used */
  48         u64 bytes_used;
  49
  50         /* optimal io alignment for this device */
  51         u32 io_align;
  52
  53         /* optimal io width for this device */
  54         u32 io_width;
  55
  56         /* minimal io size for this device */
  57         u32 sector_size;
  58
  59         /* type and info about this device */
  60         u64 type;
  61
  62         /* physical drive uuid (or lvm uuid) */
  63         u8 uuid[BTRFS_UUID_SIZE];
  64 };
  65
  66 struct btrfs_fs_devices {
  67         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
  68
  69         /* the device with this id has the most recent coyp of the super */
  70         u64 latest_devid;
  71         u64 latest_trans;
  72         u64 lowest_devid;
  73         u64 num_devices;
  74         struct block_device *latest_bdev;
  75         struct block_device *lowest_bdev;
  76         /* all of the devices in the FS */
  77         struct list_head devices;
  78
  79         /* devices not currently being allocated */
  80         struct list_head alloc_list;
  81         struct list_head list;
  82 };
  83
  84 struct btrfs_bio_stripe {
  85         struct btrfs_device *dev;
  86         u64 physical;
  87 };
  88
  89 struct btrfs_multi_bio {
  90         atomic_t stripes_pending;
  91         bio_end_io_t *end_io;
  92         void *private;
  93         int error;
  94         int num_stripes;
  95         struct btrfs_bio_stripe stripes[];
  96 };
  97
  98 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
  99                             (sizeof(struct btrfs_bio_stripe) * (n)))
 100
 101 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
 102                            struct btrfs_device *device,
 103                            u64 chunk_tree, u64 chunk_objectid,
 104                            u64 chunk_offset,
 105                            u64 num_bytes, u64 *start);
 106 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 107                     u64 logical, u64 *length,
 108                     struct btrfs_multi_bio **multi_ret, int mirror_num);
 109 int btrfs_read_sys_array(struct btrfs_root *root);
 110 int btrfs_read_chunk_tree(struct btrfs_root *root);
 111 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 112                       struct btrfs_root *extent_root, u64 *start,
 113                       u64 *num_bytes, u64 type);
 114 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 115 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 116 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 117                   int mirror_num);
 118 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
 119 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 120                        int flags, void *holder);
 121 int btrfs_scan_one_device(const char *path, int flags, void *holder,
 122                           struct btrfs_fs_devices **fs_devices_ret);
 123 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 124 int btrfs_add_device(struct btrfs_trans_handle *trans,
 125                      struct btrfs_root *root,
 126                      struct btrfs_device *device);
 127 int btrfs_cleanup_fs_uuids(void);
 128 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
 129 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
 130                       u64 logical, struct page *page);
 131 #endif