From patchwork Fri Oct 25 17:10:05 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anand Jain X-Patchwork-Id: 3096971 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 33DC99F372 for ; Fri, 25 Oct 2013 17:02:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id F008F20343 for ; Fri, 25 Oct 2013 17:02:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9687E20320 for ; Fri, 25 Oct 2013 17:02:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752770Ab3JYRCC (ORCPT ); Fri, 25 Oct 2013 13:02:02 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:20402 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751788Ab3JYRCB (ORCPT ); Fri, 25 Oct 2013 13:02:01 -0400 Received: from acsinet22.oracle.com (acsinet22.oracle.com [141.146.126.238]) by aserp1040.oracle.com (Sentrion-MTA-4.3.1/Sentrion-MTA-4.3.1) with ESMTP id r9PH20rU009323 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 25 Oct 2013 17:02:00 GMT Received: from aserz7022.oracle.com (aserz7022.oracle.com [141.146.126.231]) by acsinet22.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r9PH1xW9008748 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 25 Oct 2013 17:01:59 GMT Received: from abhmt107.oracle.com (abhmt107.oracle.com [141.146.116.59]) by aserz7022.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r9PH1x8r008742 for ; Fri, 25 Oct 2013 17:01:59 GMT Received: from wish.sg.oracle.com (/10.186.101.18) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 25 Oct 2013 10:01:59 -0700 From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH] btrfs: add framework to read fs info from btrfs-control Date: Sat, 26 Oct 2013 01:10:05 +0800 Message-Id: <1382721007-5531-1-git-send-email-anand.jain@oracle.com> X-Mailer: git-send-email 1.8.1.164.g2d0029e X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This adds ioctl BTRFS_IOC_GET_FSIDS which reads the fs info through the btrfs-control Signed-off-by: Anand Jain --- fs/btrfs/super.c | 47 ++++++++++++++++++++++++++++++++++++++----- fs/btrfs/volumes.c | 33 ++++++++++++++++++++++++++++++ fs/btrfs/volumes.h | 2 + include/uapi/linux/btrfs.h | 19 +++++++++++++++++ 4 files changed, 95 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 0991fb1..bae53ba 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1641,38 +1641,73 @@ static struct file_system_type btrfs_fs_type = { }; MODULE_ALIAS_FS("btrfs"); +static int btrfs_ioc_get_fslist(void __user *arg) +{ + int ret = 0; + u64 sz_fslist_arg; + u64 sz_fslist; + struct btrfs_ioctl_fslist_args *fslist_arg; + struct btrfs_ioctl_fslist *fslist; + + sz_fslist_arg = sizeof(*fslist_arg); + fslist_arg = memdup_user(arg, sz_fslist_arg); + + sz_fslist = sizeof(*fslist) * fslist_arg->count; + kfree(fslist_arg); + fslist_arg = memdup_user(arg, sz_fslist_arg + sz_fslist); + fslist = (struct btrfs_ioctl_fslist *) (fslist_arg + sz_fslist_arg); + + ret = btrfs_get_fslist(fslist_arg, fslist); + + fslist->self_sz = sz_fslist; + fslist_arg->self_sz = sz_fslist_arg; + + if (copy_to_user(arg, fslist_arg, sz_fslist_arg + sz_fslist)) + ret = -EFAULT; + + kfree(fslist_arg); + return ret; +} + /* * used by btrfsctl to scan devices when no FS is mounted */ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - struct btrfs_ioctl_vol_args *vol; + struct btrfs_ioctl_vol_args *vol = NULL; struct btrfs_fs_devices *fs_devices; int ret = -ENOTTY; + void __user *argp = (void __user *)arg; if (!capable(CAP_SYS_ADMIN)) return -EPERM; - vol = memdup_user((void __user *)arg, sizeof(*vol)); - if (IS_ERR(vol)) - return PTR_ERR(vol); - switch (cmd) { case BTRFS_IOC_SCAN_DEV: + vol = memdup_user((void __user *)arg, sizeof(*vol)); + if (IS_ERR(vol)) + return PTR_ERR(vol); ret = btrfs_scan_one_device(vol->name, FMODE_READ, &btrfs_fs_type, &fs_devices); + kfree(vol); break; case BTRFS_IOC_DEVICES_READY: + vol = memdup_user((void __user *)arg, sizeof(*vol)); + if (IS_ERR(vol)) + return PTR_ERR(vol); ret = btrfs_scan_one_device(vol->name, FMODE_READ, &btrfs_fs_type, &fs_devices); + kfree(vol); if (ret) break; ret = !(fs_devices->num_devices == fs_devices->total_devices); break; + case BTRFS_IOC_GET_FSLIST: + ret = btrfs_ioc_get_fslist(argp); + break; } - kfree(vol); return ret; } diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index fe0f2ef..a7b8f26 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6284,3 +6284,36 @@ int btrfs_scratch_superblock(struct btrfs_device *device) return 0; } + +/* return 1 if allocation count exceed the num of fs list + * in the kernel + */ +int btrfs_get_fslist(struct btrfs_ioctl_fslist_args *fslist_arg, + struct btrfs_ioctl_fslist *fslist) +{ + u64 cnt = 0, ucnt; + struct btrfs_fs_devices *fs_devices; + + ucnt = fslist_arg->count; + + list_for_each_entry(fs_devices, &fs_uuids, list) { + if (cnt < ucnt) { + memcpy(fslist->fsid, fs_devices->fsid, + BTRFS_FSID_SIZE); + fslist->num_devices = fs_devices->num_devices; + fslist->missing_devices = fs_devices->missing_devices; + fslist->total_devices = fs_devices->total_devices; + + if (fs_devices->opened) + fslist->flags = BTRFS_FS_MOUNTED; + + fslist = (struct btrfs_ioctl_fslist *) fslist + + sizeof(*fslist); + } + cnt++; + } + fslist_arg->count = cnt; + if (cnt > ucnt) + return 1; + return 0; +} diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index b72f540..e68a1c8 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -388,4 +388,6 @@ static inline void btrfs_dev_stat_reset(struct btrfs_device *dev, { btrfs_dev_stat_set(dev, index, 0); } +int btrfs_get_fslist(struct btrfs_ioctl_fslist_args *fslist_arg, + struct btrfs_ioctl_fslist *fslist); #endif diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index 45e6189..6690551 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -512,6 +512,23 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) } } +/* fs flags */ +#define BTRFS_FS_MOUNTED (1LLU << 0) + +struct btrfs_ioctl_fslist { + __u64 self_sz; /* in/out */ + __u8 fsid[BTRFS_FSID_SIZE]; /* out */ + __u64 num_devices; + __u64 missing_devices; + __u64 total_devices; + __u64 flags; +}; + +struct btrfs_ioctl_fslist_args { + __u64 self_sz; /* in/out */ + __u64 count; /* out */ +}; + #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ struct btrfs_ioctl_vol_args) #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ @@ -606,5 +623,7 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code) struct btrfs_ioctl_dev_replace_args) #define BTRFS_IOC_FILE_EXTENT_SAME _IOWR(BTRFS_IOCTL_MAGIC, 54, \ struct btrfs_ioctl_same_args) +#define BTRFS_IOC_GET_FSLIST _IOWR(BTRFS_IOCTL_MAGIC, 56, \ + struct btrfs_ioctl_fslist_args) #endif /* _UAPI_LINUX_BTRFS_H */