src/lxc/storage/storage.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #ifndef __LXC_STORAGE_H
   4 #define __LXC_STORAGE_H
   5
   6 #include <stdint.h>
   7 #include <sys/mount.h>
   8
   9 #include <lxc/lxccontainer.h>
  10
  11 #if IS_BIONIC
  12 #include <../include/lxcmntent.h>
  13 #else
  14 #include <mntent.h>
  15 #endif
  16
  17 #ifndef MS_DIRSYNC
  18 #define MS_DIRSYNC 128
  19 #endif
  20
  21 #ifndef MS_REC
  22 #define MS_REC 16384
  23 #endif
  24
  25 #ifndef MNT_DETACH
  26 #define MNT_DETACH 2
  27 #endif
  28
  29 #ifndef MS_SLAVE
  30 #define MS_SLAVE (1 << 19)
  31 #endif
  32
  33 #ifndef MS_RELATIME
  34 #define MS_RELATIME (1 << 21)
  35 #endif
  36
  37 #ifndef MS_STRICTATIME
  38 #define MS_STRICTATIME (1 << 24)
  39 #endif
  40
  41 #define DEFAULT_FS_SIZE 1073741824
  42 #define DEFAULT_FSTYPE "ext4"
  43
  44 #define LXC_STORAGE_INTERNAL_OVERLAY_RESTORE  (1 << 6)
  45
  46 struct lxc_storage;
  47
  48 struct lxc_storage_ops {
  49         /* detect whether path is of this bdev type */
  50         bool (*detect)(const char *path);
  51
  52         /* mount requires src and dest to be set. */
  53         int (*mount)(struct lxc_storage *bdev);
  54         int (*umount)(struct lxc_storage *bdev);
  55         int (*destroy)(struct lxc_storage *bdev);
  56         int (*create)(struct lxc_storage *bdev, const char *dest, const char *n,
  57                       struct bdev_specs *specs);
  58         /* given original mount, rename the paths for cloned container */
  59         int (*clone_paths)(struct lxc_storage *orig, struct lxc_storage *new,
  60                            const char *oldname, const char *cname,
  61                            const char *oldpath, const char *lxcpath, int snap,
  62                            uint64_t newsize, struct lxc_conf *conf);
  63         bool (*copy)(struct lxc_conf *conf, struct lxc_storage *orig,
  64                      struct lxc_storage *new, uint64_t newsize);
  65         bool (*snapshot)(struct lxc_conf *conf, struct lxc_storage *orig,
  66                          struct lxc_storage *new, uint64_t newsize);
  67         bool can_snapshot;
  68         bool can_backup;
  69 };
  70
  71 /* When lxc is mounting a rootfs, then src will be the "lxc.rootfs.path" value,
  72  * dest will be the mount dir (i.e. "<libdir>/lxc")  When clone or create is
  73  * doing so, then dest will be "<lxcpath>/<lxcname>/rootfs", since we may need
  74  * to rsync from one to the other.
  75  */
  76 struct lxc_storage {
  77         const struct lxc_storage_ops *ops;
  78         const char *type;
  79         char *src;
  80         char *dest;
  81         char *mntopts;
  82         /* Turn the following into a union if need be. */
  83         /* lofd is the open fd for the mounted loopback file. */
  84         int lofd;
  85         /* index for the connected nbd device. */
  86         int nbd_idx;
  87         int flags;
  88 };
  89
  90 /**
  91  * storage_is_dir : Check whether the roots is a directory. This function will
  92  *                  trust the config file. If the config file key
  93  *                  lxc.rootfs.path is set to <storage type>:<container path>
  94  *                  the confile parser will have split this into <storage type>
  95  *                  and <container path> and set the <bdev_type> member in the
  96  *                  lxc_rootfs struct to <storage type> and the <path> member
  97  *                  will be set to a clean <container path> without the <storage
  98  *                  type> prefix. This is the new, clean way of handling storage
  99  *                  type specifications.  If the <storage type> prefix is not
 100  *                  detected liblxc will try to detect the storage type.
 101  */
 102 extern bool storage_is_dir(struct lxc_conf *conf);
 103 extern bool storage_can_backup(struct lxc_conf *conf);
 104
 105 extern struct lxc_storage *storage_init(struct lxc_conf *conf);
 106
 107 extern struct lxc_storage *storage_copy(struct lxc_container *c,
 108                                         const char *cname, const char *lxcpath,
 109                                         const char *bdevtype, int flags,
 110                                         const char *bdevdata, uint64_t newsize,
 111                                         bool *needs_rdep);
 112 extern struct lxc_storage *storage_create(const char *dest, const char *type,
 113                                           const char *cname,
 114                                           struct bdev_specs *specs);
 115 extern void storage_put(struct lxc_storage *bdev);
 116 extern bool storage_destroy(struct lxc_conf *conf);
 117 extern bool rootfs_is_blockdev(struct lxc_conf *conf);
 118 extern const char *lxc_storage_get_path(char *src, const char *prefix);
 119
 120 #endif /* #define __LXC_STORAGE_H */