From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:33972 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935525Ab3FUH2X (ORCPT ); Fri, 21 Jun 2013 03:28:23 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by userp1040.oracle.com (Sentrion-MTA-4.3.1/Sentrion-MTA-4.3.1) with ESMTP id r5L7M46c030194 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 21 Jun 2013 07:22:05 GMT Received: from aserz7022.oracle.com (aserz7022.oracle.com [141.146.126.231]) by ucsinet22.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r5L7SLq5015213 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 21 Jun 2013 07:28:22 GMT Received: from abhmt113.oracle.com (abhmt113.oracle.com [141.146.116.65]) by aserz7022.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r5L7SL1V029771 for ; Fri, 21 Jun 2013 07:28:21 GMT From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH 2/2 v3] btrfs: obtain used_bytes in BTRFS_IOC_FS_INFO ioctl Date: Fri, 21 Jun 2013 15:32:28 +0800 Message-Id: <1371799948-14176-1-git-send-email-anand.jain@oracle.com> In-Reply-To: <1370876355-16584-3-git-send-email-anand.jain@oracle.com> References: <1370876355-16584-3-git-send-email-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: btrfs-progs has to read fs info from the kernel to read the latest info instead of reading it from the disks, which generally is a stale info after certain critical operation. getting used_bytes parameter will help to fix btrfs filesystem show --kernel to show the current info of the fs v2->v3: everything is changed dropped the plan to introduce the new ioctl, as of now filesystem show could manage if we add the used_bytes parameter to the BTRFS_IOC_FS_INFO and Update the title from add framework to read fs info and dev info from the kernel Signed-off-by: Anand Jain --- fs/btrfs/ioctl.c | 16 ++++++++++++++-- include/uapi/linux/btrfs.h | 3 ++- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 0e7bcc5..082c9fc 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2384,7 +2384,10 @@ static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) struct btrfs_ioctl_fs_info_args *fi_args; struct btrfs_device *device; struct btrfs_device *next; - struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; + struct btrfs_fs_info *info = root->fs_info; + struct btrfs_fs_devices *fs_devices = info->fs_devices; + struct btrfs_space_info *si; + u64 used_bytes = 0; int ret = 0; if (!capable(CAP_SYS_ADMIN)) @@ -2394,8 +2397,17 @@ static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) if (!fi_args) return -ENOMEM; + rcu_read_lock(); + list_for_each_entry_rcu(si, &info->space_info, list) { + used_bytes += si->bytes_used + si->bytes_reserved + + si->bytes_pinned + si->bytes_readonly + + si->bytes_may_use; + } + rcu_read_unlock(); + fi_args->used_bytes = used_bytes; + fi_args->num_devices = fs_devices->num_devices; - memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); + memcpy(&fi_args->fsid, info->fsid, sizeof(fi_args->fsid)); mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index de3ec34..44bac0c 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -181,7 +181,8 @@ struct btrfs_ioctl_fs_info_args { __u64 max_id; /* out */ __u64 num_devices; /* out */ __u8 fsid[BTRFS_FSID_SIZE]; /* out */ - __u64 reserved[124]; /* pad to 1k */ + __u64 used_bytes; /* out */ + __u64 reserved[123]; /* pad to 1k */ }; /* balance control ioctl modes */ -- 1.8.1.227.g44fe835