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