| Message ID | 20170712072050.2531-1-anand.jain@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 12, 2017 at 03:20:50PM +0800, Anand Jain wrote: > Unless the top level is mounted there is no way to know the > details of all the subvolume. For example: > > mount -o subvol=sv1/newsv1 /dev/sdb /btrfs > > btrfs su list /btrfs > ID 257 gen 12 top level 5 path sv1 > ID 258 gen 9 top level 257 path sv1/snap > ID 259 gen 11 top level 257 path sv1/newsv1 > > You can't subvol show for sv1 and sv1/snap as its paths aren't > accessible to the user unless the its top level is mounted. > > This patch adds two new options to the existing btrfs subvol show > cli. They are --rootid/-r or --uuid/-u, with this now the user will > be able to look for a subvolume using the rootid OR the uuid. Sounds good. > ./btrfs su show -r 257 /btrfs > sv1 > Name: sv1 > UUID: 30129358-c69d-3e4a-a662-29509cc69c95 > Parent UUID: - > Received UUID: - > Creation time: 2017-07-11 20:32:57 +0800 > Subvolume ID: 257 > Generation: 12 > Gen at creation: 7 > Parent ID: 5 > Top level ID: 5 > Flags: - > Snapshot(s): > sv1/snap > > Signed-off-by: Anand Jain <anand.jain@oracle.com> > --- > btrfs-list.c | 4 +++- > cmds-subvolume.c | 44 +++++++++++++++++++++++++++++++++++++++++--- > utils.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > utils.h | 5 ++++- > 4 files changed, 100 insertions(+), 5 deletions(-) > > diff --git a/btrfs-list.c b/btrfs-list.c > index 8eec05ea797f..92a537f425f3 100644 > --- a/btrfs-list.c > +++ b/btrfs-list.c > @@ -1582,7 +1582,9 @@ int btrfs_get_subvol(int fd, struct root_info *the_ri) > rbn = rb_next(rbn); > continue; > } > - if (!comp_entry_with_rootid(the_ri, ri, 0)) { > + > + if (!comp_entry_with_rootid(the_ri, ri, 0) || > + !uuid_compare(the_ri->uuid, ri->uuid)) { > memcpy(the_ri, ri, offsetof(struct root_info, path)); > the_ri->path = strdup_or_null(ri->path); > the_ri->name = strdup_or_null(ri->name); > diff --git a/cmds-subvolume.c b/cmds-subvolume.c > index de6204eabeaf..1fa54d1b24cf 100644 > --- a/cmds-subvolume.c > +++ b/cmds-subvolume.c > @@ -891,8 +891,11 @@ static int cmd_subvol_find_new(int argc, char **argv) > } > > static const char * const cmd_subvol_show_usage[] = { > - "btrfs subvolume show <subvol-path>", > + "btrfs subvolume show [options] <subvol-path>|<mnt>", > "Show more information of the subvolume", > + "-r|--rootid rootid of the subvol to show", > + "-u|--uuid uuid of the subvol to show", > + "If no option is specified <subvol-path> will be shown.", > NULL > }; > > @@ -907,8 +910,36 @@ static int cmd_subvol_show(int argc, char **argv) > int fd = -1; > int ret = 1; > DIR *dirstream1 = NULL; > + int by_rootid = 0; > + int by_uuid = 0; > + u64 rootid_arg; > + u8 uuid_arg[BTRFS_UUID_SIZE]; > > - clean_args_no_options(argc, argv, cmd_subvol_show_usage); > + while (1) { > + int c; > + static const struct option long_options[] = { > + { "rootid", required_argument, NULL, 'r'}, > + { "uuid", required_argument, NULL, 'u'}, > + { NULL, 0, NULL, 0 } > + }; > + > + c = getopt_long(argc, argv, "r:u:", long_options, NULL); > + if (c < 0) > + break; > + > + switch (c) { > + case 'r': > + rootid_arg = arg_strtou64(optarg); > + by_rootid = 1; > + break; > + case 'u': > + uuid_parse(optarg, uuid_arg); > + by_uuid = 1; > + break; > + default: > + usage(cmd_subvol_show_usage); > + } > + } > > if (check_argc_exact(argc - optind, 1)) > usage(cmd_subvol_show_usage); > @@ -921,7 +952,14 @@ static int cmd_subvol_show(int argc, char **argv) > goto out; > } > > - ret = get_subvol_info(fullpath, &get_ri); > + if (by_rootid) { > + ret = get_subvol_info_by_rootid(fullpath, &get_ri, rootid_arg); > + } else if (by_uuid) { > + ret = get_subvol_info_by_uuid(fullpath, &get_ri, uuid_arg); > + } else { > + ret = get_subvol_info(fullpath, &get_ri); > + } Here rootid takes precedence if there are both options specified. I think this should be handled as invalid syntax. If the rootid and uuid do not match, it's not well defined and can cause silent breakage. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/btrfs-list.c b/btrfs-list.c index 8eec05ea797f..92a537f425f3 100644 --- a/btrfs-list.c +++ b/btrfs-list.c @@ -1582,7 +1582,9 @@ int btrfs_get_subvol(int fd, struct root_info *the_ri) rbn = rb_next(rbn); continue; } - if (!comp_entry_with_rootid(the_ri, ri, 0)) { + + if (!comp_entry_with_rootid(the_ri, ri, 0) || + !uuid_compare(the_ri->uuid, ri->uuid)) { memcpy(the_ri, ri, offsetof(struct root_info, path)); the_ri->path = strdup_or_null(ri->path); the_ri->name = strdup_or_null(ri->name); diff --git a/cmds-subvolume.c b/cmds-subvolume.c index de6204eabeaf..1fa54d1b24cf 100644 --- a/cmds-subvolume.c +++ b/cmds-subvolume.c @@ -891,8 +891,11 @@ static int cmd_subvol_find_new(int argc, char **argv) } static const char * const cmd_subvol_show_usage[] = { - "btrfs subvolume show <subvol-path>", + "btrfs subvolume show [options] <subvol-path>|<mnt>", "Show more information of the subvolume", + "-r|--rootid rootid of the subvol to show", + "-u|--uuid uuid of the subvol to show", + "If no option is specified <subvol-path> will be shown.", NULL }; @@ -907,8 +910,36 @@ static int cmd_subvol_show(int argc, char **argv) int fd = -1; int ret = 1; DIR *dirstream1 = NULL; + int by_rootid = 0; + int by_uuid = 0; + u64 rootid_arg; + u8 uuid_arg[BTRFS_UUID_SIZE]; - clean_args_no_options(argc, argv, cmd_subvol_show_usage); + while (1) { + int c; + static const struct option long_options[] = { + { "rootid", required_argument, NULL, 'r'}, + { "uuid", required_argument, NULL, 'u'}, + { NULL, 0, NULL, 0 } + }; + + c = getopt_long(argc, argv, "r:u:", long_options, NULL); + if (c < 0) + break; + + switch (c) { + case 'r': + rootid_arg = arg_strtou64(optarg); + by_rootid = 1; + break; + case 'u': + uuid_parse(optarg, uuid_arg); + by_uuid = 1; + break; + default: + usage(cmd_subvol_show_usage); + } + } if (check_argc_exact(argc - optind, 1)) usage(cmd_subvol_show_usage); @@ -921,7 +952,14 @@ static int cmd_subvol_show(int argc, char **argv) goto out; } - ret = get_subvol_info(fullpath, &get_ri); + if (by_rootid) { + ret = get_subvol_info_by_rootid(fullpath, &get_ri, rootid_arg); + } else if (by_uuid) { + ret = get_subvol_info_by_uuid(fullpath, &get_ri, uuid_arg); + } else { + ret = get_subvol_info(fullpath, &get_ri); + } + if (ret) { if (ret < 0) { error("Failed to get subvol info %s: %s", diff --git a/utils.c b/utils.c index d2489e70f8d8..250e6cc76cbc 100644 --- a/utils.c +++ b/utils.c @@ -2432,6 +2432,58 @@ out: return ret; } +int get_subvol_info_by_rootid(const char *mnt, struct root_info *get_ri, u64 r_id) +{ + int fd; + int ret; + DIR *dirstream = NULL; + + fd = btrfs_open_dir(mnt, &dirstream, 1); + if (fd < 0) + return -EINVAL; + + memset(get_ri, 0, sizeof(*get_ri)); + get_ri->root_id = r_id; + + if (r_id == BTRFS_FS_TREE_OBJECTID) + ret = btrfs_get_toplevel_subvol(fd, get_ri); + else + ret = btrfs_get_subvol(fd, get_ri); + + if (ret) + error("can't find rootid '%llu' on '%s': %d", r_id, mnt, ret); + + close_file_or_dir(fd, dirstream); + + return ret; +} + +int get_subvol_info_by_uuid(const char *mnt, struct root_info *get_ri, u8 *uuid_arg) +{ + int fd; + int ret; + DIR *dirstream = NULL; + + fd = btrfs_open_dir(mnt, &dirstream, 1); + if (fd < 0) + return -EINVAL; + + memset(get_ri, 0, sizeof(*get_ri)); + uuid_copy(get_ri->uuid, uuid_arg); + + ret = btrfs_get_subvol(fd, get_ri); + if (ret) { + char uuid_parsed[BTRFS_UUID_UNPARSED_SIZE]; + uuid_unparse(uuid_arg, uuid_parsed); + error("can't find uuid '%s' on '%s': %d", + uuid_parsed, mnt, ret); + } + + close_file_or_dir(fd, dirstream); + + return ret; +} + /* Set the seed manually */ void init_rand_seed(u64 seed) { diff --git a/utils.h b/utils.h index 24d0a200d2b2..b5931a9b3370 100644 --- a/utils.h +++ b/utils.h @@ -134,7 +134,10 @@ int test_isdir(const char *path); const char *subvol_strip_mountpoint(const char *mnt, const char *full_path); int get_subvol_info(const char *fullpath, struct root_info *get_ri); - +int get_subvol_info_by_rootid(const char *mnt, struct root_info *get_ri, + u64 rootid_arg); +int get_subvol_info_by_uuid(const char *mnt, struct root_info *get_ri, + u8 *uuid_arg); int find_next_key(struct btrfs_path *path, struct btrfs_key *key); const char* btrfs_group_type_str(u64 flag); const char* btrfs_group_profile_str(u64 flag);
Unless the top level is mounted there is no way to know the details of all the subvolume. For example: mount -o subvol=sv1/newsv1 /dev/sdb /btrfs btrfs su list /btrfs ID 257 gen 12 top level 5 path sv1 ID 258 gen 9 top level 257 path sv1/snap ID 259 gen 11 top level 257 path sv1/newsv1 You can't subvol show for sv1 and sv1/snap as its paths aren't accessible to the user unless the its top level is mounted. This patch adds two new options to the existing btrfs subvol show cli. They are --rootid/-r or --uuid/-u, with this now the user will be able to look for a subvolume using the rootid OR the uuid. ./btrfs su show -r 257 /btrfs sv1 Name: sv1 UUID: 30129358-c69d-3e4a-a662-29509cc69c95 Parent UUID: - Received UUID: - Creation time: 2017-07-11 20:32:57 +0800 Subvolume ID: 257 Generation: 12 Gen at creation: 7 Parent ID: 5 Top level ID: 5 Flags: - Snapshot(s): sv1/snap Signed-off-by: Anand Jain <anand.jain@oracle.com> --- btrfs-list.c | 4 +++- cmds-subvolume.c | 44 +++++++++++++++++++++++++++++++++++++++++--- utils.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ utils.h | 5 ++++- 4 files changed, 100 insertions(+), 5 deletions(-)