From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from rcsinet15.oracle.com ([148.87.113.117]:46626 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752867Ab2HCJvf (ORCPT ); Fri, 3 Aug 2012 05:51:35 -0400 From: Anand jain To: linux-btrfs@vger.kernel.org Cc: Ilya Dryomov Subject: [PATCH 5/9] Btrfs-progs: bring 'subvol get-default' back in Date: Fri, 3 Aug 2012 17:48:54 +0800 Message-Id: <1343987338-10612-7-git-send-email-Anand.Jain@oracle.com> In-Reply-To: <1343987338-10612-1-git-send-email-Anand.Jain@oracle.com> References: <1343822481-26707-1-git-send-email-Anand.Jain@oracle.com> <1343987338-10612-1-git-send-email-Anand.Jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Ilya Dryomov Commit bab2c565 accidentally broke 'subvol get-default' command by removing almost all of the underlying code. Bring it back with some fixes and improvements. Signed-off-by: Ilya Dryomov --- btrfs-list.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++- ctree.h | 2 + 2 files changed, 82 insertions(+), 1 deletions(-) diff --git a/btrfs-list.c b/btrfs-list.c index 911b238..f2a6e19 100644 --- a/btrfs-list.c +++ b/btrfs-list.c @@ -554,6 +554,60 @@ build: return full; } +static int get_default_subvolid(int fd, u64 *default_id) +{ + struct btrfs_ioctl_search_args args; + struct btrfs_ioctl_search_key *sk = &args.key; + struct btrfs_ioctl_search_header *sh; + u64 found = 0; + int ret; + + memset(&args, 0, sizeof(args)); + + /* + * search for a dir item with a name 'default' in the tree of + * tree roots, it should point us to a default root + */ + sk->tree_id = 1; + + /* don't worry about ancient format and request only one item */ + 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; + + ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args); + if (ret < 0) + return ret; + + /* the ioctl returns the number of items it found in nr_items */ + if (sk->nr_items == 0) + goto out; + + sh = (struct btrfs_ioctl_search_header *)args.buf; + + if (sh->type == BTRFS_DIR_ITEM_KEY) { + struct btrfs_dir_item *di; + int name_len; + char *name; + + di = (struct btrfs_dir_item *)(sh + 1); + name_len = btrfs_stack_dir_name_len(di); + name = (char *)(di + 1); + + if (!strncmp("default", name, name_len)) + found = btrfs_disk_key_objectid(&di->location); + } + +out: + *default_id = found; + return 0; +} + static int __list_subvol_search(int fd, struct root_lookup *root_lookup) { int ret; @@ -667,12 +721,32 @@ static int __list_subvol_fill_paths(int fd, struct root_lookup *root_lookup) return 0; } -int list_subvols(int fd, int print_parent) +int list_subvols(int fd, int print_parent, int get_default) { struct root_lookup root_lookup; struct rb_node *n; + u64 default_id; int ret; + if (get_default) { + ret = get_default_subvolid(fd, &default_id); + if (ret) { + fprintf(stderr, "ERROR: can't perform the search - %s\n", + strerror(errno)); + return ret; + } + if (default_id == 0) { + fprintf(stderr, "ERROR: 'default' dir item not found\n"); + return ret; + } + + /* no need to resolve roots if FS_TREE is default */ + if (default_id == BTRFS_FS_TREE_OBJECTID) { + printf("ID 5 (FS_TREE)\n"); + return ret; + } + } + ret = __list_subvol_search(fd, &root_lookup); if (ret) { fprintf(stderr, "ERROR: can't perform the search - %s\n", @@ -700,6 +774,11 @@ int list_subvols(int fd, int print_parent) char *path; entry = rb_entry(n, struct root_info, rb_node); + if (get_default && entry->root_id != default_id) { + n = rb_prev(n); + continue; + } + resolve_root(&root_lookup, entry, &parent_id, &level, &path); if (print_parent) { printf("ID %llu parent %llu top level %llu path %s\n", diff --git a/ctree.h b/ctree.h index 07691c7..32b591c 100644 --- a/ctree.h +++ b/ctree.h @@ -1459,6 +1459,8 @@ BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8); BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16); BTRFS_SETGET_FUNCS(dir_transid, struct btrfs_dir_item, transid, 64); +BTRFS_SETGET_STACK_FUNCS(stack_dir_name_len, struct btrfs_dir_item, name_len, 16); + static inline void btrfs_dir_item_key(struct extent_buffer *eb, struct btrfs_dir_item *item, struct btrfs_disk_key *key) -- 1.7.1