From patchwork Thu Sep 21 04:10:15 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zygo Blaxell X-Patchwork-Id: 9963211 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BAEF76056E for ; Thu, 21 Sep 2017 04:10:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AE71F2930B for ; Thu, 21 Sep 2017 04:10:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A361C29310; Thu, 21 Sep 2017 04:10:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 015C1292E9 for ; Thu, 21 Sep 2017 04:10:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751462AbdIUEKf (ORCPT ); Thu, 21 Sep 2017 00:10:35 -0400 Received: from james.kirk.hungrycats.org ([174.142.39.145]:48028 "EHLO james.kirk.hungrycats.org" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751068AbdIUEKe (ORCPT ); Thu, 21 Sep 2017 00:10:34 -0400 Received: by james.kirk.hungrycats.org (Postfix, from userid 1002) id 4562670E4A73; Thu, 21 Sep 2017 00:10:34 -0400 (EDT) From: Zygo Blaxell To: linux-btrfs@vger.kernel.org Subject: [PATCH 2/3] btrfs: add a flags argument to LOGICAL_INO and call it LOGICAL_INO_V2 Date: Thu, 21 Sep 2017 00:10:15 -0400 Message-Id: <20170921041016.14752-3-ce3g8jdj@umail.furryterror.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170921041016.14752-1-ce3g8jdj@umail.furryterror.org> References: <20170921041016.14752-1-ce3g8jdj@umail.furryterror.org> Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Now that check_extent_in_eb()'s extent offset filter can be turned off, we need a way to do it from userspace. Add a 'flags' field to the btrfs_logical_ino_args structure to disable extent offset filtering, taking the place of one of the reserved[] fields. Previous versions of LOGICAL_INO neglected to check whether any of the reserved fields have non-zero values. Assigning meaning to those fields now may change the behavior of existing programs that left these fields uninitialized. To avoid any surprises, define a new ioctl LOGICAL_INO_V2 which uses the same argument layout as LOGICAL_INO, but uses one of the reserved fields for flags. The V2 ioctl explicitly checks that unsupported flag bits are zero so that userspace can probe for future feature bits as they are defined. If the other reserved fields are used in the future, one of the remaining flag bits could specify that the other reserved fields are valid, so we don't need to check those for now. Since the memory layouts and behavior of the two ioctls' arguments are almost identical, there is no need for a separate function for logical_to_ino_v2 (contrast with tree_search_v2 vs tree_search). A version parameter and an 'if' statement will suffice. Now that we have a flags field in logical_ino_args, add a flag BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET to get the behavior we want, and pass it down the stack to iterate_inodes_from_logical. Signed-off-by: Zygo Blaxell --- fs/btrfs/ioctl.c | 21 ++++++++++++++++++--- include/uapi/linux/btrfs.h | 8 +++++++- 2 files changed, 25 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index b7de32568082..2bc3a9588d1d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -4536,13 +4536,14 @@ static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) } static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, - void __user *arg) + void __user *arg, int version) { int ret = 0; int size; struct btrfs_ioctl_logical_ino_args *loi; struct btrfs_data_container *inodes = NULL; struct btrfs_path *path = NULL; + bool ignore_offset; if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -4551,6 +4552,17 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, if (IS_ERR(loi)) return PTR_ERR(loi); + if (version == 1) { + ignore_offset = false; + } else { + /* Only accept flags we have defined so far */ + if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) { + ret = -EINVAL; + goto out_loi; + } + ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET; + } + path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; @@ -4566,7 +4578,7 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, } ret = iterate_inodes_from_logical(loi->logical, fs_info, path, - build_ino_list, inodes, false); + build_ino_list, inodes, ignore_offset); if (ret == -EINVAL) ret = -ENOENT; if (ret < 0) @@ -4580,6 +4592,7 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, out: btrfs_free_path(path); kvfree(inodes); +out_loi: kfree(loi); return ret; @@ -5550,7 +5563,9 @@ long btrfs_ioctl(struct file *file, unsigned int case BTRFS_IOC_INO_PATHS: return btrfs_ioctl_ino_to_path(root, argp); case BTRFS_IOC_LOGICAL_INO: - return btrfs_ioctl_logical_to_ino(fs_info, argp); + return btrfs_ioctl_logical_to_ino(fs_info, argp, 1); + case BTRFS_IOC_LOGICAL_INO_V2: + return btrfs_ioctl_logical_to_ino(fs_info, argp, 2); case BTRFS_IOC_SPACE_INFO: return btrfs_ioctl_space_info(fs_info, argp); case BTRFS_IOC_SYNC: { diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index 378230c163d5..0b3de597e04f 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -608,10 +608,14 @@ struct btrfs_ioctl_ino_path_args { struct btrfs_ioctl_logical_ino_args { __u64 logical; /* in */ __u64 size; /* in */ - __u64 reserved[4]; + __u64 flags; /* in, v2 only */ + __u64 reserved[3]; /* struct btrfs_data_container *inodes; out */ __u64 inodes; }; +/* Return every ref to the extent, not just those containing logical block. + * Requires logical == extent bytenr. */ +#define BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET (1ULL << 0) enum btrfs_dev_stat_values { /* disk I/O failure stats */ @@ -835,5 +839,7 @@ enum btrfs_err_code { struct btrfs_ioctl_feature_flags[3]) #define BTRFS_IOC_RM_DEV_V2 _IOW(BTRFS_IOCTL_MAGIC, 58, \ struct btrfs_ioctl_vol_args_v2) +#define BTRFS_IOC_LOGICAL_INO_V2 _IOWR(BTRFS_IOCTL_MAGIC, 59, \ + struct btrfs_ioctl_logical_ino_args) #endif /* _UAPI_LINUX_BTRFS_H */