Btrfs-progs: add -u to show subvol uuid

Applications would need to know the uuid to manage the configurations
associated with the subvol and snapshots

Signed-off-by: Anand Jain <anand.jain@oracle.com>

diff --git a/btrfs-list.c b/btrfs-list.c
index edd12a4..514cac7 100644 (file)
--- a/btrfs-list.c
+++ b/btrfs-list.c
@@ -34,6 +34,7 @@
 #include "ctree.h"
 #include "transaction.h"
 #include "utils.h"
+#include <uuid/uuid.h>
 
 /* we store all the roots we find in an rbtree so that we can
  * search for them later.
@@ -63,6 +64,8 @@ struct root_info {
        /* creation time of this root in sec*/
        time_t otime;
 
+       u8 uuid[BTRFS_UUID_SIZE];
+
        /* path from the subvol we live in to this root, including the
         * root's name.  This is null until we do the extra lookup ioctl.
         */
@@ -188,7 +191,7 @@ static struct root_info *tree_search(struct rb_root *root, u64 root_id)
  */
 static int add_root(struct root_lookup *root_lookup,
                    u64 root_id, u64 ref_tree, u64 dir_id, char *name,
-                   int name_len, u64 *gen, time_t ot)
+                   int name_len, u64 *gen, time_t ot, void *uuid)
 {
        struct root_info *ri;
        struct rb_node *ret;
@@ -210,6 +213,11 @@ static int add_root(struct root_lookup *root_lookup,
                ri->gen = *gen;
        ri->otime = ot;
 
+       if (uuid) 
+               memcpy(&ri->uuid, uuid, BTRFS_UUID_SIZE);
+       else
+               memset(&ri->uuid, 0, BTRFS_UUID_SIZE);
+
        ret = tree_insert(&root_lookup->root, root_id, ref_tree, gen,
                          &ri->rb_node);
        if (ret) {
@@ -220,7 +228,7 @@ static int add_root(struct root_lookup *root_lookup,
 }
 
 static int update_root(struct root_lookup *root_lookup, u64 root_id, u64 gen,
-                       time_t ot)
+                       time_t ot, void *uuid)
 {
        struct root_info *ri;
 
@@ -231,6 +239,11 @@ static int update_root(struct root_lookup *root_lookup, u64 root_id, u64 gen,
        }
        ri->gen = gen;
        ri->otime = ot;
+       if (uuid)
+               memcpy(&ri->uuid, uuid, BTRFS_UUID_SIZE);
+       else
+               memset(&ri->uuid, 0, BTRFS_UUID_SIZE);
+
        return 0;
 }
 
@@ -665,6 +678,7 @@ static int __list_subvol_search(int fd, struct root_lookup *root_lookup)
        int i;
        int get_gen = 0;
        time_t t;
+       u8 uuid[BTRFS_UUID_SIZE];
 
        root_lookup_init(root_lookup);
        memset(&args, 0, sizeof(args));
@@ -718,16 +732,20 @@ again:
                                dir_id = btrfs_stack_root_ref_dirid(ref);
 
                                add_root(root_lookup, sh->objectid, sh->offset,
-                                        dir_id, name, name_len, NULL, 0);
+                                        dir_id, name, name_len, NULL, 0, NULL);
                        } else if (get_gen && sh->type == BTRFS_ROOT_ITEM_KEY) {
                                ri = (struct btrfs_root_item *)(args.buf + off);
                                gen = btrfs_root_generation(ri);
-                               if(ri->generation == ri->generation_v2)
+                               if(ri->generation == ri->generation_v2) {
                                        t = ri->otime.sec;
-                               else
+                                       memcpy(uuid, ri->uuid, BTRFS_UUID_SIZE);
+                               } else {
                                        t = 0;
+                                       memset(uuid, 0, BTRFS_UUID_SIZE);
+                               }
 
-                               update_root(root_lookup, sh->objectid, gen, t);
+                               update_root(root_lookup, sh->objectid, gen, t,
+                                       uuid);
                        }
 
                        off += sh->len;
@@ -818,19 +836,24 @@ static int __list_snapshot_search(int fd, struct root_lookup *root_lookup)
                for (i = 0; i < sk->nr_items; i++) {
                        struct btrfs_root_item *item;
                        time_t  t;
+                       u8 uuid[BTRFS_UUID_SIZE];
+
                        sh = (struct btrfs_ioctl_search_header *)(args.buf +
                                                                  off);
                        off += sizeof(*sh);
                        if (sh->type == BTRFS_ROOT_ITEM_KEY && sh->offset) {
                                item = (struct btrfs_root_item *)(args.buf + off);
-                               if(item->generation == item->generation_v2)
+                               if(item->generation == item->generation_v2) {
                                        t = item->otime.sec;
-                               else
+                                       memcpy(uuid, item->uuid, BTRFS_UUID_SIZE);
+                               } else {
                                        t = 0;
+                                       memset(uuid, 0, BTRFS_UUID_SIZE);
+                               }
                                gen = sh->offset;
 
                                add_root(root_lookup, sh->objectid, 0,
-                                        0, NULL, 0, &gen, t);
+                                        0, NULL, 0, &gen, t, uuid);
                        }
                        off += sh->len;
 
@@ -877,12 +900,13 @@ static int __list_subvol_fill_paths(int fd, struct root_lookup *root_lookup)
        return 0;
 }
 
-int list_subvols(int fd, int print_parent, int get_default)
+int list_subvols(int fd, int print_parent, int get_default, int print_uuid)
 {
        struct root_lookup root_lookup;
        struct rb_node *n;
        u64 default_id;
        int ret;
+       char uuidparse[37];
 
        if (get_default) {
                ret = get_default_subvolid(fd, &default_id);
@@ -937,16 +961,44 @@ int list_subvols(int fd, int print_parent, int get_default)
 
                resolve_root(&root_lookup, entry, &parent_id, &level, &path);
                if (print_parent) {
-                       printf("ID %llu gen %llu parent %llu top level %llu path %s\n",
-                               (unsigned long long)entry->root_id,
-                               (unsigned long long)entry->gen,
-                               (unsigned long long)parent_id,
-                               (unsigned long long)level, path);
+                       if (print_uuid) {
+                               if (uuid_is_null(entry->uuid))
+                                       strcpy(uuidparse, "-");
+                               else
+                                       uuid_unparse(entry->uuid, uuidparse);
+                               printf("ID %llu gen %llu parent %llu top level %llu"
+                                       " uuid %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)parent_id,
+                                       (unsigned long long)level,
+                                       uuidparse, path);
+                       } else {
+                               printf("ID %llu gen %llu parent %llu top level"
+                                       " %llu path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)parent_id,
+                                       (unsigned long long)level, path);
+                       }
                } else {
-                       printf("ID %llu gen %llu top level %llu path %s\n",
-                               (unsigned long long)entry->root_id,
-                               (unsigned long long)entry->gen,
-                               (unsigned long long)level, path);
+                       if (print_uuid) {
+                               if (uuid_is_null(entry->uuid))
+                                       strcpy(uuidparse, "-");
+                               else
+                                       uuid_unparse(entry->uuid, uuidparse);
+                               printf("ID %llu gen %llu top level %llu"
+                                       " uuid %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)level,
+                                       uuidparse, path);
+                       } else {
+                               printf("ID %llu gen %llu top level %llu path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)level, path);
+                       }
                }
 
                free(path);
@@ -956,7 +1008,7 @@ int list_subvols(int fd, int print_parent, int get_default)
        return ret;
 }
 
-int list_snapshots(int fd, int print_parent, int order)
+int list_snapshots(int fd, int print_parent, int order, int print_uuid)
 {
        struct root_lookup root_lookup;
        struct root_lookup root_lookup_snap;
@@ -1001,6 +1053,7 @@ int list_snapshots(int fd, int print_parent, int order)
                char *path;
                time_t t;
                char tstr[256];
+               char uuidparse[37];
 
                entry_snap = rb_entry(n, struct root_info, rb_node);
                entry = tree_search(&root_lookup.root, entry_snap->root_id);
@@ -1012,20 +1065,49 @@ int list_snapshots(int fd, int print_parent, int order)
                else
                        strcpy(tstr,"-");
                if (print_parent) {
-                       printf("ID %llu gen %llu cgen %llu parent %llu top level %llu "
-                               "otime %s path %s\n",
-                               (unsigned long long)entry->root_id,
-                               (unsigned long long)entry->gen,
-                               (unsigned long long)entry_snap->gen,
-                               (unsigned long long)parent_id,
-                               (unsigned long long)level, tstr, path);
+                       if (print_uuid) {
+                               if (uuid_is_null(entry->uuid))
+                                       strcpy(uuidparse, "-");
+                               else
+                                       uuid_unparse(entry->uuid, uuidparse);
+                               printf("ID %llu gen %llu cgen %llu parent %llu"
+                                       " top level %llu otime %s uuid %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)entry_snap->gen,
+                                       (unsigned long long)parent_id,
+                                       (unsigned long long)level,
+                                       tstr, uuidparse, path);
+                       } else {
+                               printf("ID %llu gen %llu cgen %llu parent %llu"
+                                       " top level %llu otime %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)entry_snap->gen,
+                                       (unsigned long long)parent_id,
+                                       (unsigned long long)level, tstr, path);
+                       }
                } else {
-                       printf("ID %llu gen %llu cgen %llu top level %llu "
-                               "otime %s path %s\n",
-                               (unsigned long long)entry->root_id,
-                               (unsigned long long)entry->gen,
-                               (unsigned long long)entry_snap->gen,
-                               (unsigned long long)level, tstr, path);
+                       if (print_uuid) {
+                               if (uuid_is_null(entry->uuid))
+                                       strcpy(uuidparse, "-");
+                               else
+                                       uuid_unparse(entry->uuid, uuidparse);
+                               printf("ID %llu gen %llu cgen %llu top level %llu "
+                                       "otime %s uuid %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)entry_snap->gen,
+                                       (unsigned long long)level,
+                                       tstr, uuidparse, path);
+                       } else {
+                               printf("ID %llu gen %llu cgen %llu top level %llu "
+                                       "otime %s path %s\n",
+                                       (unsigned long long)entry->root_id,
+                                       (unsigned long long)entry->gen,
+                                       (unsigned long long)entry_snap->gen,
+                                       (unsigned long long)level, tstr, path);
+                       }
                }
 
                free(path);

diff --git a/cmds-subvolume.c b/cmds-subvolume.c
index 8a81d36..aaf5dde 100644 (file)
--- a/cmds-subvolume.c
+++ b/cmds-subvolume.c
@@ -31,7 +31,7 @@
 #include "commands.h"
 
 /* btrfs-list.c */
-int list_subvols(int fd, int print_parent, int get_default);
+int list_subvols(int fd, int print_parent, int print_uuid, int get_default);
 int find_updated_files(int fd, u64 root_id, u64 oldest_gen);
 
 static const char * const subvolume_cmd_group_usage[] = {
@@ -278,10 +278,11 @@ static int cmd_subvol_list(int argc, char **argv)
        int print_snap_only = 0;
        int order = 0;
        char *subvol;
+       int print_uuid = 0;
 
        optind = 1;
        while(1) {
-               int c = getopt(argc, argv, "ps:");
+               int c = getopt(argc, argv, "ps:u");
                if (c < 0)
                        break;
 
@@ -293,6 +294,9 @@ static int cmd_subvol_list(int argc, char **argv)
                        print_snap_only = 1;
                        order = atoi(optarg);
                        break;
+               case 'u':
+                       print_uuid =1;
+                       break;
                default:
                        usage(cmd_subvol_list_usage);
                }
@@ -319,9 +323,9 @@ static int cmd_subvol_list(int argc, char **argv)
                return 12;
        }
        if (!print_snap_only)
-               ret = list_subvols(fd, print_parent, 0);
+               ret = list_subvols(fd, print_parent, 0, print_uuid);
        else
-               ret = list_snapshots(fd, print_parent, order);
+               ret = list_snapshots(fd, print_parent, order, print_uuid);
        if (ret)
                return 19;
        return 0;
@@ -502,7 +506,7 @@ static int cmd_subvol_get_default(int argc, char **argv)
                fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
                return 12;
        }
-       ret = list_subvols(fd, 0, 1);
+       ret = list_subvols(fd, 0, 1, 0);
        if (ret)
                return 19;
        return 0;