From patchwork Wed Aug 8 08:54:51 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: zhoubo X-Patchwork-Id: 1293261 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id D27DEDF223 for ; Wed, 8 Aug 2012 08:55:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932566Ab2HHIzR (ORCPT ); Wed, 8 Aug 2012 04:55:17 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:34740 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S932460Ab2HHIzI (ORCPT ); Wed, 8 Aug 2012 04:55:08 -0400 X-IronPort-AV: E=Sophos;i="4.77,732,1336320000"; d="scan'208";a="5579870" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 08 Aug 2012 16:54:05 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id q788t59C010151; Wed, 8 Aug 2012 16:55:06 +0800 Received: from localhost.localdomain ([10.167.225.128]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2012080816552753-197703 ; Wed, 8 Aug 2012 16:55:27 +0800 Message-ID: <5022295B.2010400@cn.fujitsu.com> Date: Wed, 08 Aug 2012 16:54:51 +0800 From: zhoubo User-Agent: Thunderbird 2.0.0.17 (X11/20081009) MIME-Version: 1.0 To: btrfs community CC: Goffredo Baroncelli Subject: [PATCH 2/3 V2] Btrfs-progs: enhance btrfs subvol list only to show read-only snapshots X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/08 16:55:27, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/08/08 16:55:28, Serialize complete at 2012/08/08 16:55:28 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Zhou Bo We want 'btrfs subvolume list' only to list readonly subvolumes, this patch set introduces a new option 'r' to implement it. You can use the command like that: btrfs subvolume list -r Signed-off-by: Zhou Bo --- btrfs-list.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++------ cmds-subvolume.c | 13 +++++++--- ctree.h | 2 + 3 files changed, 71 insertions(+), 12 deletions(-) diff --git a/btrfs-list.c b/btrfs-list.c index 693d241..9c10b9e 100644 --- a/btrfs-list.c +++ b/btrfs-list.c @@ -608,7 +608,46 @@ out: return 0; } -static int __list_subvol_search(int fd, struct root_lookup *root_lookup) +static int is_readonly_subvol(int fd, u64 objectid) +{ + int ret; + struct btrfs_ioctl_search_args args; + struct btrfs_ioctl_search_key *sk = &args.key; + struct btrfs_ioctl_search_header *sh; + unsigned long off = 0; + int found = 0; + struct btrfs_root_item *item; + + memset(&args, 0, sizeof(args)); + + /* search in the tree of tree roots */ + sk->tree_id = BTRFS_ROOT_TREE_OBJECTID; + sk->min_objectid = objectid; + sk->max_objectid = objectid; + sk->max_type = BTRFS_ROOT_ITEM_KEY; + sk->min_type = BTRFS_ROOT_ITEM_KEY; + sk->max_offset = (u64)-1; + sk->max_transid = (u64)-1; + sk->nr_items = 1; + ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args); + if (ret < 0) + return ret; + if (sk->nr_items == 0) { + errno = -ENOENT; + found = -1; + goto out; + } + sh = (struct btrfs_ioctl_search_header *)args.buf; + off += sizeof(*sh); + item = (struct btrfs_root_item *)(args.buf + off); + if (item->flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) + found = 1; +out: + return found; +} + +static int __list_subvol_search(int fd, struct root_lookup *root_lookup, + int list_ro) { int ret; struct btrfs_ioctl_search_args args; @@ -668,9 +707,23 @@ static int __list_subvol_search(int fd, struct root_lookup *root_lookup) name_len = btrfs_stack_root_ref_name_len(ref); name = (char *)(ref + 1); dir_id = btrfs_stack_root_ref_dirid(ref); - - add_root(root_lookup, sh->objectid, sh->offset, - dir_id, name, name_len); + if (list_ro) { + int subvol_readonly = + is_readonly_subvol(fd, + sh->objectid); + if (subvol_readonly < 0) { + return subvol_readonly; + } else if (subvol_readonly) { + add_root(root_lookup, + sh->objectid, + sh->offset, dir_id, + name, name_len); + } + } else { + add_root(root_lookup, sh->objectid, + sh->offset, dir_id, + name, name_len); + } } off += sh->len; @@ -719,7 +772,7 @@ 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 list_ro) { struct root_lookup root_lookup; struct rb_node *n; @@ -745,7 +798,7 @@ int list_subvols(int fd, int print_parent, int get_default) } } - ret = __list_subvol_search(fd, &root_lookup); + ret = __list_subvol_search(fd, &root_lookup, list_ro); if (ret) { fprintf(stderr, "ERROR: can't perform the search - %s\n", strerror(errno)); @@ -788,7 +841,6 @@ int list_subvols(int fd, int print_parent, int get_default) (unsigned long long)entry->root_id, (unsigned long long)level, path); } - free(path); n = rb_prev(n); } @@ -983,7 +1035,7 @@ char *path_for_root(int fd, u64 root) char *ret_path = NULL; int ret; - ret = __list_subvol_search(fd, &root_lookup); + ret = __list_subvol_search(fd, &root_lookup, 0); if (ret < 0) return ERR_PTR(ret); diff --git a/cmds-subvolume.c b/cmds-subvolume.c index 3508ce6..90c5c4e 100644 --- a/cmds-subvolume.c +++ b/cmds-subvolume.c @@ -219,10 +219,11 @@ static int cmd_subvol_delete(int argc, char **argv) } static const char * const cmd_subvol_list_usage[] = { - "btrfs subvolume list [-p] ", + "btrfs subvolume list [-pr] ", "List subvolumes (and snapshots)", "", "-p print parent ID", + "-r only list readonly snapshots", NULL }; @@ -231,15 +232,19 @@ static int cmd_subvol_list(int argc, char **argv) int fd; int ret; int print_parent = 0; + int list_ro = 0; char *subvol; optind = 1; while(1) { - int c = getopt(argc, argv, "p"); + int c = getopt(argc, argv, "pr"); if (c < 0) break; switch(c) { + case 'r': + list_ro = 1; + break; case 'p': print_parent = 1; break; @@ -268,7 +273,7 @@ static int cmd_subvol_list(int argc, char **argv) fprintf(stderr, "ERROR: can't access '%s'\n", subvol); return 12; } - ret = list_subvols(fd, print_parent, 0); + ret = list_subvols(fd, print_parent, 0, list_ro); if (ret) return 19; return 0; @@ -428,7 +433,7 @@ 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; diff --git a/ctree.h b/ctree.h index 71e387b..12da31a 100644 --- a/ctree.h +++ b/ctree.h @@ -138,6 +138,8 @@ static int btrfs_csum_sizes[] = { 4, 0 }; #define BTRFS_FT_XATTR 8 #define BTRFS_FT_MAX 9 +#define BTRFS_ROOT_SUBVOL_RDONLY (1ULL << 0) + /* * the key defines the order in the tree, and so it also defines (optimal) * block layout. objectid corresonds to the inode number. The flags