Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753358Ab0BUGbf (ORCPT ); Sun, 21 Feb 2010 01:31:35 -0500 Received: from mx1.redhat.com ([209.132.183.28]:26665 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752925Ab0BUGbe (ORCPT ); Sun, 21 Feb 2010 01:31:34 -0500 Message-ID: <4B80D416.7090207@redhat.com> Date: Sun, 21 Feb 2010 14:35:02 +0800 From: Cong Wang User-Agent: Thunderbird 2.0.0.23 (X11/20091001) MIME-Version: 1.0 To: Octavian Purdila CC: David Miller , Linux Kernel Network Developers , Linux Kernel Developers , "Eric W. Biederman" Subject: Re: [net-next PATCH v5 2/3] sysctl: add proc_do_large_bitmap References: <1266532346-11604-1-git-send-email-opurdila@ixiacom.com> In-Reply-To: <1266532346-11604-1-git-send-email-opurdila@ixiacom.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2634 Lines: 71 Octavian Purdila wrote: > The new function can be used to read/write large bitmaps via /proc. A > comma separated range format is used for compact output and input > (e.g. 1,3-4,10-10). > > Writing into the file will first reset the bitmap then update it > based on the given input. > > Signed-off-by: Octavian Purdila > Cc: WANG Cong > Cc: Eric W. Biederman > --- > include/linux/sysctl.h | 2 + > kernel/sysctl.c | 122 ++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 124 insertions(+), 0 deletions(-) > > diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h > index f66014c..7bb5cb6 100644 > --- a/include/linux/sysctl.h > +++ b/include/linux/sysctl.h > @@ -980,6 +980,8 @@ extern int proc_doulongvec_minmax(struct ctl_table *, int, > void __user *, size_t *, loff_t *); > extern int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int, > void __user *, size_t *, loff_t *); > +extern int proc_do_large_bitmap(struct ctl_table *, int, > + void __user *, size_t *, loff_t *); > > /* > * Register a set of sysctl names by calling register_sysctl_table > diff --git a/kernel/sysctl.c b/kernel/sysctl.c > index 5259727..ef2c13d 100644 > --- a/kernel/sysctl.c > +++ b/kernel/sysctl.c > @@ -2635,6 +2635,128 @@ static int proc_do_cad_pid(struct ctl_table *table, int write, > return 0; > } > > +/** > + * proc_do_large_bitmap - read/write from/to a large bitmap > + * @table: the sysctl table > + * @write: %TRUE if this is a write to the sysctl file > + * @buffer: the user buffer > + * @lenp: the size of the user buffer > + * @ppos: file position > + * > + * The bitmap is stored at table->data and the bitmap length (in bits) > + * in table->maxlen. > + * > + * We use a range comma separated format (e.g. 1,3-4,10-10) so that > + * large bitmaps may be represented in a compact manner. Writing into > + * the file will clear the bitmap then update it with the given input. My test shows it still accepts spaces, e.g. echo '50000 50003 50005' > ip_local_reserved_ports works same as echo '50000,50003,50005' > ip_local_reserved_ports Is this expected? We will only accept commas, right? Also, if I write an invalid value, it does reject this, but the previous value in that file is cleared, shouldn't we keep the previous one? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/