From patchwork Mon Feb 5 20:05:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Overstreet X-Patchwork-Id: 13546198 Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 09A7A12BF03 for ; Mon, 5 Feb 2024 20:06:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707163574; cv=none; b=EUQlaK8WzpOQ7c5w1VJQlVLV+xqANMaf5SUOE3XlTOHW3ucZH1tBXrtA8jszM74YNAvAAF5sQZ74ECvgXbz6P7mDB6OJkHAEcyHmVoMdW1TAQwVbV2jY886Dgs7uoTrcUBg5qW97FcG7wBaSCTYjn+h6HHE36I7q+6wA6JsPTa8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707163574; c=relaxed/simple; bh=OdB2sC0IAQE2qn+uq4dM6SEPk8ivyay4tbCp7RxmvJM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PTcnhIJBtYEvzoZQG/L+H3BXQY022tp2pY0dN7qhr6/xqeSm18Pp0aI09wwQw0l6ewzc8zydA3Mv6rV/JsnkvXL3qdtD+fRSLA5PseTgATWHIZSQeOZo2EBiqFmzcWDYQXjf0kzVhmSXc1KdWIKI/kHoGxDRngfge5anJfiPWSQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=gRu95KeB; arc=none smtp.client-ip=91.218.175.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="gRu95KeB" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1707163569; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bL8wabdGusxxHP4HD7jQgm1B3xq2dag3vBv1kp/RjKg=; b=gRu95KeBmO7sGiIbVqCYHB62tHtBwScHj+QOvvEH7lwcGJhQRU4Id4sAq77nVqqAdbHcvq WLxA7xaJjngusplfaeucaDsaWwFjXqTUcYoVvkGuf88BCvqpXeJIIR+yzYkfGRbJ+OIIvr LO2rJ4oDpy+0FUucX1pT3epb4UOcd1k= From: Kent Overstreet To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org Cc: Kent Overstreet , Christian Brauner , Jan Kara , Dave Chinner , "Darrick J. Wong" , Theodore Ts'o , Josef Bacik Subject: [PATCH 4/6] fs: FS_IOC_GETSYSFSNAME Date: Mon, 5 Feb 2024 15:05:15 -0500 Message-ID: <20240205200529.546646-5-kent.overstreet@linux.dev> In-Reply-To: <20240205200529.546646-1-kent.overstreet@linux.dev> References: <20240205200529.546646-1-kent.overstreet@linux.dev> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT Add a new ioctl for getting the sysfs name of a filesystem - the path under /sys/fs. This is going to let us standardize exporting data from sysfs across filesystems, e.g. time stats. The returned path will always be of the form "$FSTYP/$SYSFS_IDENTIFIER", where the sysfs identifier may be a UUID (for bcachefs) or a device name (xfs). Signed-off-by: Kent Overstreet Cc: Christian Brauner Cc: Jan Kara Cc: Dave Chinner Cc: "Darrick J. Wong" Cc: Theodore Ts'o Cc: Josef Bacik --- fs/ioctl.c | 17 +++++++++++++++++ include/linux/fs.h | 1 + include/uapi/linux/fs.h | 5 +++++ 3 files changed, 23 insertions(+) diff --git a/fs/ioctl.c b/fs/ioctl.c index 858801060408..cb3690811d3d 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -776,6 +776,20 @@ static int ioctl_getfsuuid(struct file *file, void __user *argp) return copy_to_user(argp, &u, sizeof(u)) ? -EFAULT : 0; } +static int ioctl_getfssysfsname(struct file *file, void __user *argp) +{ + struct super_block *sb = file_inode(file)->i_sb; + + if (!strlen(sb->s_sysfs_name)) + return -ENOIOCTLCMD; + + struct fssysfsname u = {}; + + snprintf(u.name, sizeof(u.name), "%s/%s", sb->s_type->name, sb->s_sysfs_name); + + return copy_to_user(argp, &u, sizeof(u)) ? -EFAULT : 0; +} + /* * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d. * It's just a simple helper for sys_ioctl and compat_sys_ioctl. @@ -861,6 +875,9 @@ static int do_vfs_ioctl(struct file *filp, unsigned int fd, case FS_IOC_GETFSUUID: return ioctl_getfsuuid(filp, argp); + case FS_IOC_GETFSSYSFSNAME: + return ioctl_getfssysfsname(filp, argp); + default: if (S_ISREG(inode->i_mode)) return file_ioctl(filp, cmd, argp); diff --git a/include/linux/fs.h b/include/linux/fs.h index ff41ea6c3a9c..7f23f593f17c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1258,6 +1258,7 @@ struct super_block { char s_id[32]; /* Informational name */ uuid_t s_uuid; /* UUID */ u8 s_uuid_len; /* Default 16, possibly smaller for weird filesystems */ + char s_sysfs_name[UUID_STRING_LEN + 1]; unsigned int s_max_links; diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index 0389fea87db5..6dd14a453277 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -78,6 +78,10 @@ struct fsuuid2 { __u8 fsu_uuid[16]; }; +struct fssysfsname { + __u8 name[64]; +}; + /* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */ #define FILE_DEDUPE_RANGE_SAME 0 #define FILE_DEDUPE_RANGE_DIFFERS 1 @@ -231,6 +235,7 @@ struct fsxattr { #define FS_IOC_SETFSLABEL _IOW(0x94, 50, char[FSLABEL_MAX]) #define FS_IOC_GETFSUUID _IOR(0x94, 51, struct fsuuid2) #define FS_IOC_SETFSUUID _IOW(0x94, 52, struct fsuuid2) +#define FS_IOC_GETFSSYSFSNAME _IOR(0x94, 53, struct fssysfsname) /* * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)