From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [patch 7/7] fs, notify: Add procfs fdinfo helper v6 Date: Fri, 16 Nov 2012 15:56:03 -0800 Message-ID: <20121116155603.2118394c.akpm@linux-foundation.org> References: <20121114151937.344922058@openvz.org> <20121114152239.936025193@openvz.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Al Viro , Alexey Dobriyan , Pavel Emelyanov , James Bottomley , Matthew Helsley , aneesh.kumar@linux.vnet.ibm.com, bfields@fieldses.org, oleg@redhat.com, rientjes@google.com, tvrtko.ursulin@onelan.co.uk, Andrey Vagin To: Cyrill Gorcunov Return-path: In-Reply-To: <20121114152239.936025193@openvz.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, 14 Nov 2012 19:19:44 +0400 Cyrill Gorcunov wrote: > This allow us to print out fsnotify details such as > watchee inode, device, mask and optionally a file handle. > > For inotify objects if kernel compiled with exportfs support > the output will be > > | pos: 0 > | flags: 02000000 > | inotify wd: 3 ino: 9e7e sdev: 800013 mask: 800afce ignored_mask: 0 fhandle-bytes: 8 fhandle-type: 1 f_handle: 7e9e0000640d1b6d > | inotify wd: 2 ino: a111 sdev: 800013 mask: 800afce ignored_mask: 0 fhandle-bytes: 8 fhandle-type: 1 f_handle: 11a1000020542153 > | inotify wd: 1 ino: 6b149 sdev: 800013 mask: 800afce ignored_mask: 0 fhandle-bytes: 8 fhandle-type: 1 f_handle: 49b1060023552153 This is a lousy output format. It's sort-of like a sensible set of name-value tuples: "name:value name:value name:value" but a) it has lots of random pointless whitespace after the colons and b) several of the labels have spaces in them, just to make life harder for parsing code and c) inotify-wd is secretly printed in decimal while everything else is in hex. What happens if we do something like the below (which will require a changelog update)? --- a/fs/notify/fdinfo.c~fs-notify-add-procfs-fdinfo-helper-v6-fix +++ a/fs/notify/fdinfo.c @@ -50,7 +50,7 @@ static int show_mark_fhandle(struct seq_ f.handle.handle_bytes = sizeof(f.pad); size = f.handle.handle_bytes >> 2; - ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0); + ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0); if ((ret == 255) || (ret == -ENOSPC)) { WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret); return 0; @@ -59,7 +59,7 @@ static int show_mark_fhandle(struct seq_ f.handle.handle_type = ret; f.handle.handle_bytes = size * sizeof(u32); - ret = seq_printf(m, "fhandle-bytes: %8x fhandle-type: %8x f_handle: ", + ret = seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:", f.handle.handle_bytes, f.handle.handle_type); for (i = 0; i < f.handle.handle_bytes; i++) @@ -86,8 +86,8 @@ static int inotify_fdinfo(struct seq_fil inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark); inode = igrab(mark->i.inode); if (inode) { - ret = seq_printf(m, "inotify wd: %8d ino: %16lx sdev: %8x " - "mask: %8x ignored_mask: %8x ", + ret = seq_printf(m, "inotify-wd:%x ino:%lx sdev:%x " + "mask:%x ignored_mask:%x ", inode_mark->wd, inode->i_ino, inode->i_sb->s_dev, mark->mask, mark->ignored_mask); @@ -120,15 +120,16 @@ static int fanotify_fdinfo(struct seq_fi inode = igrab(mark->i.inode); if (!inode) goto out; - ret = seq_printf(m, "fanotify ino: %16lx sdev: %8x " - "mask: %8x ignored_mask: %8x\n", + ret = seq_printf(m, "fanotify-ino:%x sdev:%x " + "mask:%x ignored_mask:%x\n", inode->i_ino, inode->i_sb->s_dev, mark->mask, mark->ignored_mask); iput(inode); } else if (mark->flags & FSNOTIFY_MARK_FLAG_VFSMOUNT) { struct mount *mnt = real_mount(mark->m.mnt); - ret = seq_printf(m, "fanotify mnt_id: %8x mask: %8x ignored_mask: %8x\n", + ret = seq_printf(m, "fanotify-mnt_id:%x mask:%x " + "ignored_mask:%x\n", mnt->mnt_id, mark->mask, mark->ignored_mask); } out: _