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 btrfs_root *dev_root;
  28         struct buffer_head *pending_io;
  29         int barriers;
  30         spinlock_t io_lock;
  31
  32         struct block_device *bdev;
  33
  34         u64 total_ios;
  35
  36         char *name;
  37
  38         /* the internal btrfs device id */
  39         u64 devid;
  40
  41         /* size of the device */
  42         u64 total_bytes;
  43
  44         /* bytes used */
  45         u64 bytes_used;
  46
  47         /* optimal io alignment for this device */
  48         u32 io_align;
  49
  50         /* optimal io width for this device */
  51         u32 io_width;
  52
  53         /* minimal io size for this device */
  54         u32 sector_size;
  55
  56         /* type and info about this device */
  57         u64 type;
  58
  59         /* physical drive uuid (or lvm uuid) */
  60         u8 uuid[BTRFS_DEV_UUID_SIZE];
  61 };
  62
  63 struct btrfs_fs_devices {
  64         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
  65
  66         /* the device with this id has the most recent coyp of the super */
  67         u64 latest_devid;
  68         u64 latest_trans;
  69         u64 lowest_devid;
  70         u64 num_devices;
  71         struct block_device *latest_bdev;
  72         struct block_device *lowest_bdev;
  73         struct list_head devices;
  74         struct list_head list;
  75 };
  76
  77 struct btrfs_bio_stripe {
  78         struct btrfs_device *dev;
  79         u64 physical;
  80 };
  81
  82 struct btrfs_multi_bio {
  83         atomic_t stripes_pending;
  84         bio_end_io_t *end_io;
  85         void *private;
  86         int error;
  87         int num_stripes;
  88         struct btrfs_bio_stripe stripes[];
  89 };
  90
  91 #define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
  92                             (sizeof(struct btrfs_bio_stripe) * (n)))
  93
  94 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
  95                            struct btrfs_device *device,
  96                            u64 owner, u64 num_bytes, u64 *start);
  97 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
  98                     u64 logical, u64 *length,
  99                     struct btrfs_multi_bio **multi_ret, int mirror_num);
 100 int btrfs_read_sys_array(struct btrfs_root *root);
 101 int btrfs_read_chunk_tree(struct btrfs_root *root);
 102 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 103                       struct btrfs_root *extent_root, u64 *start,
 104                       u64 *num_bytes, u64 type);
 105 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 106 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 107 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 108                   int mirror_num);
 109 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
 110 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 111                        int flags, void *holder);
 112 int btrfs_scan_one_device(const char *path, int flags, void *holder,
 113                           struct btrfs_fs_devices **fs_devices_ret);
 114 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
 115 int btrfs_add_device(struct btrfs_trans_handle *trans,
 116                      struct btrfs_root *root,
 117                      struct btrfs_device *device);
 118 int btrfs_cleanup_fs_uuids(void);
 119 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
 120 #endif