/*
- * Copyright (c) [2011-2014] Novell, Inc.
+ * Copyright (c) [2011-2015] Novell, Inc.
*
* All Rights Reserved.
*
namespace snapper
{
- // See btrfsprogs source code for references.
+ namespace BtrfsUtils
+ {
+ // See btrfsprogs source code for references.
- bool
- is_subvolume(const struct stat& stat)
- {
- return stat.st_ino == 256 && S_ISDIR(stat.st_mode);
- }
+ bool
+ is_subvolume(const struct stat& stat)
+ {
+ return stat.st_ino == 256 && S_ISDIR(stat.st_mode);
+ }
- bool
- is_subvolume_read_only(int fd)
- {
- __u64 flags;
- if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_SUBVOL_GETFLAGS) failed", errno);
- return flags & BTRFS_SUBVOL_RDONLY;
- }
+ bool
+ is_subvolume_read_only(int fd)
+ {
+ __u64 flags;
+ if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SUBVOL_GETFLAGS) failed", errno);
+ return flags & BTRFS_SUBVOL_RDONLY;
+ }
- void
- create_subvolume(int fddst, const string& name)
- {
- struct btrfs_ioctl_vol_args args;
- memset(&args, 0, sizeof(args));
- strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
+ void
+ create_subvolume(int fddst, const string& name)
+ {
+ struct btrfs_ioctl_vol_args args;
+ memset(&args, 0, sizeof(args));
- if (ioctl(fddst, BTRFS_IOC_SUBVOL_CREATE, &args) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_SUBVOL_CREATE) failed", errno);
- }
+ strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
+ if (ioctl(fddst, BTRFS_IOC_SUBVOL_CREATE, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SUBVOL_CREATE) failed", errno);
+ }
- void
- create_snapshot(int fd, int fddst, const string& name, bool read_only, qgroup_t qgroup)
- {
- struct btrfs_ioctl_vol_args_v2 args_v2;
- memset(&args_v2, 0, sizeof(args_v2));
- args_v2.fd = fd;
- args_v2.flags = read_only ? BTRFS_SUBVOL_RDONLY : 0;
- strncpy(args_v2.name, name.c_str(), sizeof(args_v2.name) - 1);
+ void
+ create_snapshot(int fd, int fddst, const string& name, bool read_only, qgroup_t qgroup)
+ {
+ struct btrfs_ioctl_vol_args_v2 args_v2;
+ memset(&args_v2, 0, sizeof(args_v2));
+
+ args_v2.fd = fd;
+ args_v2.flags = read_only ? BTRFS_SUBVOL_RDONLY : 0;
+ strncpy(args_v2.name, name.c_str(), sizeof(args_v2.name) - 1);
#ifdef ENABLE_BTRFS_QUOTA
- if (qgroup != no_qgroup)
- {
- size_t size = sizeof(btrfs_qgroup_inherit) + sizeof(((btrfs_qgroup_inherit*) 0)->qgroups[0]);
- vector<char> buffer(size, 0);
- struct btrfs_qgroup_inherit* inherit = (btrfs_qgroup_inherit*) &buffer[0];
-
- inherit->num_qgroups = 1;
- inherit->num_ref_copies = 0;
- inherit->num_excl_copies = 0;
- inherit->qgroups[0] = qgroup;
-
- args_v2.flags |= BTRFS_SUBVOL_QGROUP_INHERIT;
- args_v2.size = size;
- args_v2.qgroup_inherit = inherit;
- }
+ if (qgroup != no_qgroup)
+ {
+ size_t size = sizeof(btrfs_qgroup_inherit) + sizeof(((btrfs_qgroup_inherit*) 0)->qgroups[0]);
+ vector<char> buffer(size, 0);
+ struct btrfs_qgroup_inherit* inherit = (btrfs_qgroup_inherit*) &buffer[0];
+
+ inherit->num_qgroups = 1;
+ inherit->num_ref_copies = 0;
+ inherit->num_excl_copies = 0;
+ inherit->qgroups[0] = qgroup;
+
+ args_v2.flags |= BTRFS_SUBVOL_QGROUP_INHERIT;
+ args_v2.size = size;
+ args_v2.qgroup_inherit = inherit;
+ }
#endif
- if (ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args_v2) == 0)
- return;
- else if (errno != ENOTTY && errno != EINVAL)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_CREATE_V2) failed", errno);
+ if (ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args_v2) == 0)
+ return;
+ else if (errno != ENOTTY && errno != EINVAL)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_CREATE_V2) failed", errno);
- struct btrfs_ioctl_vol_args args;
- memset(&args, 0, sizeof(args));
+ struct btrfs_ioctl_vol_args args;
+ memset(&args, 0, sizeof(args));
- args.fd = fd;
- strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
+ args.fd = fd;
+ strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
- if (ioctl(fddst, BTRFS_IOC_SNAP_CREATE, &args) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_CREATE) failed", errno);
- }
+ if (ioctl(fddst, BTRFS_IOC_SNAP_CREATE, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_CREATE) failed", errno);
+ }
- void
- delete_subvolume(int fd, const string& name)
- {
- struct btrfs_ioctl_vol_args args;
- memset(&args, 0, sizeof(args));
+ void
+ delete_subvolume(int fd, const string& name)
+ {
+ struct btrfs_ioctl_vol_args args;
+ memset(&args, 0, sizeof(args));
- strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
+ strncpy(args.name, name.c_str(), sizeof(args.name) - 1);
- if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_DESTROY) failed", errno);
- }
+ if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SNAP_DESTROY) failed", errno);
+ }
#ifdef ENABLE_ROLLBACK
- void
- set_default_id(int fd, unsigned long long id)
- {
- if (ioctl(fd, BTRFS_IOC_DEFAULT_SUBVOL, &id) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_DEFAULT_SUBVOL) failed", errno);
- }
+ void
+ set_default_id(int fd, subvolid_t id)
+ {
+ if (ioctl(fd, BTRFS_IOC_DEFAULT_SUBVOL, &id) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_DEFAULT_SUBVOL) failed", errno);
+ }
- unsigned long long
- get_default_id(int fd)
- {
- struct btrfs_ioctl_search_args args;
- memset(&args, 0, sizeof(args));
-
- struct btrfs_ioctl_search_key* sk = &args.key;
- sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
- sk->nr_items = 1;
- sk->max_objectid = BTRFS_ROOT_TREE_DIR_OBJECTID;
- sk->min_objectid = BTRFS_ROOT_TREE_DIR_OBJECTID;
- sk->max_type = BTRFS_DIR_ITEM_KEY;
- sk->min_type = BTRFS_DIR_ITEM_KEY;
- sk->max_offset = (__u64) -1;
- sk->max_transid = (__u64) -1;
-
- if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_TREE_SEARCH) failed", errno);
-
- if (sk->nr_items == 0)
- throw std::runtime_error("sk->nr_items == 0");
-
- struct btrfs_ioctl_search_header* sh = (struct btrfs_ioctl_search_header*) args.buf;
- if (sh->type != BTRFS_DIR_ITEM_KEY)
- throw std::runtime_error("sh->type != BTRFS_DIR_ITEM_KEY");
-
- struct btrfs_dir_item* di = (struct btrfs_dir_item*)(sh + 1);
- int name_len = btrfs_stack_dir_name_len(di);
- const char* name = (const char*)(di + 1);
- if (strncmp("default", name, name_len) != 0)
- throw std::runtime_error("name != default");
-
- return btrfs_disk_key_objectid(&di->location);
- }
+ subvolid_t
+ get_default_id(int fd)
+ {
+ struct btrfs_ioctl_search_args args;
+ memset(&args, 0, sizeof(args));
+
+ struct btrfs_ioctl_search_key* sk = &args.key;
+ sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
+ sk->nr_items = 1;
+ sk->max_objectid = BTRFS_ROOT_TREE_DIR_OBJECTID;
+ sk->min_objectid = BTRFS_ROOT_TREE_DIR_OBJECTID;
+ sk->max_type = BTRFS_DIR_ITEM_KEY;
+ sk->min_type = BTRFS_DIR_ITEM_KEY;
+ sk->max_offset = (__u64) -1;
+ sk->max_transid = (__u64) -1;
+
+ if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_TREE_SEARCH) failed", errno);
+
+ if (sk->nr_items == 0)
+ throw std::runtime_error("sk->nr_items == 0");
+
+ struct btrfs_ioctl_search_header* sh = (struct btrfs_ioctl_search_header*) args.buf;
+ if (sh->type != BTRFS_DIR_ITEM_KEY)
+ throw std::runtime_error("sh->type != BTRFS_DIR_ITEM_KEY");
+
+ struct btrfs_dir_item* di = (struct btrfs_dir_item*)(sh + 1);
+ int name_len = btrfs_stack_dir_name_len(di);
+ const char* name = (const char*)(di + 1);
+ if (strncmp("default", name, name_len) != 0)
+ throw std::runtime_error("name != default");
+
+ return btrfs_disk_key_objectid(&di->location);
+ }
- string
- get_subvolume(int fd, unsigned long long id)
- {
- char path[BTRFS_PATH_NAME_MAX + 1];
+ string
+ get_subvolume(int fd, subvolid_t id)
+ {
+ char path[BTRFS_PATH_NAME_MAX + 1];
- if (btrfs_subvolid_resolve(fd, path, sizeof(path), id) != 0)
- throw std::runtime_error("btrfs_subvolid_resolve failed");
+ if (btrfs_subvolid_resolve(fd, path, sizeof(path), id) != 0)
+ throw std::runtime_error("btrfs_subvolid_resolve failed");
- path[BTRFS_PATH_NAME_MAX] = '\0';
- return path;
- }
+ path[BTRFS_PATH_NAME_MAX] = '\0';
+ return path;
+ }
+#endif
- unsigned long long
- get_id(int fd)
- {
- struct btrfs_ioctl_ino_lookup_args args;
- memset(&args, 0, sizeof(args));
- args.treeid = 0;
- args.objectid = BTRFS_FIRST_FREE_OBJECTID;
- if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args) != 0)
- throw runtime_error_with_errno("ioctl(BTRFS_IOC_INO_LOOKUP) failed", errno);
+ subvolid_t
+ get_id(int fd)
+ {
+ struct btrfs_ioctl_ino_lookup_args args;
+ memset(&args, 0, sizeof(args));
+ args.treeid = 0;
+ args.objectid = BTRFS_FIRST_FREE_OBJECTID;
- return args.treeid;
- }
+ if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_INO_LOOKUP) failed", errno);
-#endif
+ return args.treeid;
+ }
- qgroup_t
- make_qgroup(uint64_t level, uint64_t id)
- {
- return (level << 48) | id;
- }
+ qgroup_t
+ make_qgroup(uint64_t level, subvolid_t id)
+ {
+ return (level << 48) | id;
+ }
- qgroup_t
- make_qgroup(const string& str)
- {
- string::size_type pos = str.find('/');
- if (pos == string::npos)
- throw std::runtime_error("parsing qgroup failed");
-
- std::istringstream a(str.substr(0, pos));
- uint64_t level = 0;
- a >> level;
- if (a.fail() || !a.eof())
- throw std::runtime_error("parsing qgroup failed");
-
- std::istringstream b(str.substr(pos + 1));
- uint64_t id = 0;
- b >> id;
- if (b.fail() || !b.eof())
- throw std::runtime_error("parsing qgroup failed");
-
- return make_qgroup(level, id);
+ qgroup_t
+ make_qgroup(const string& str)
+ {
+ string::size_type pos = str.find('/');
+ if (pos == string::npos)
+ throw std::runtime_error("parsing qgroup failed");
+
+ std::istringstream a(str.substr(0, pos));
+ uint64_t level = 0;
+ a >> level;
+ if (a.fail() || !a.eof())
+ throw std::runtime_error("parsing qgroup failed");
+
+ std::istringstream b(str.substr(pos + 1));
+ subvolid_t id = 0;
+ b >> id;
+ if (b.fail() || !b.eof())
+ throw std::runtime_error("parsing qgroup failed");
+
+ return make_qgroup(level, id);
+ }
+
+
+ bool
+ does_subvolume_exist(int fd, subvolid_t subvolid)
+ {
+ struct btrfs_ioctl_search_args args;
+ struct btrfs_ioctl_search_key* sk = &args.key;
+
+ sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
+ sk->min_objectid = subvolid;
+ sk->max_objectid = subvolid;
+ sk->min_type = BTRFS_ROOT_ITEM_KEY;
+ sk->max_type = BTRFS_ROOT_ITEM_KEY;
+ sk->min_offset = 0;
+ sk->max_offset = (u64) -1;
+ sk->min_transid = 0;
+ sk->max_transid = (u64) -1;
+ sk->nr_items = 1;
+
+ if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_TREE_SEARCH) failed", errno);
+
+ return sk->nr_items == 0;
+ }
+
+
+ void
+ sync(int fd)
+ {
+ if (ioctl(fd, BTRFS_IOC_SYNC) != 0)
+ throw runtime_error_with_errno("ioctl(BTRFS_IOC_SYNC) failed", errno);
+ }
+
}
}
projects / thirdparty / snapper.git / commitdiff
