From patchwork Sun May 1 15:47:12 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugo Mills X-Patchwork-Id: 746102 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.3) with ESMTP id p41Flc87017688 for ; Sun, 1 May 2011 15:47:40 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760742Ab1EAPrb (ORCPT ); Sun, 1 May 2011 11:47:31 -0400 Received: from frost.carfax.org.uk ([212.13.194.111]:2758 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758063Ab1EAPrV (ORCPT ); Sun, 1 May 2011 11:47:21 -0400 Received: from ruthven.carfax.org.uk ([10.0.0.10]) by frost.carfax.org.uk with esmtp (Exim 4.69) (envelope-from ) id 1QGYrd-0004Ze-Fm; Sun, 01 May 2011 15:47:17 +0000 Received: from [10.0.0.10] (helo=ruthven.carfax.org.uk) by ruthven.carfax.org.uk with esmtp (Exim 4.72) (envelope-from ) id 1QGYrd-0004hn-7U; Sun, 01 May 2011 16:47:17 +0100 From: Hugo Mills To: Btrfs mailing list , Chris Mason Subject: [PATCH v6 4/8] Run userspace tool in background for balances. Date: Sun, 1 May 2011 16:47:12 +0100 Message-Id: <5813d6898efdce8d0acb5f95e5bce70f991c2026.1304262467.git.hugo@carfax.org.uk> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: References: In-Reply-To: References: To: linux-btrfs@vger.kernel.org X-frost.carfax.org.uk-Spam-Score: -0.0 (/) X-frost.carfax.org.uk-Spam-Report: Spam detection software, running on the system "spamd1.lon.bitfolk.com", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: This patch makes a balance operation fork and detach from the current terminal, to run the userspace side of the balance in the background. Introduce a --wait switch so that a synchronous balance can be done if the user requires. [...] Content analysis details: (-0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Sun, 01 May 2011 15:47:40 +0000 (UTC) This patch makes a balance operation fork and detach from the current terminal, to run the userspace side of the balance in the background. Introduce a --wait switch so that a synchronous balance can be done if the user requires. Signed-off-by: Hugo Mills --- btrfs.c | 8 ++++---- btrfs_cmds.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++-- man/btrfs.8.in | 14 ++++++++------ 3 files changed, 62 insertions(+), 12 deletions(-) diff --git a/btrfs.c b/btrfs.c index 93f7886..7b42658 100644 --- a/btrfs.c +++ b/btrfs.c @@ -91,12 +91,12 @@ static struct Command commands[] = { "filesystem df", "\n" "Show space usage information for a mount point\n." }, - { do_balance, 1, - "filesystem balance", "\n" + { do_balance, -1, + "filesystem balance", "[-w|--wait] \n" "Balance the chunks across the device." }, - { do_balance, 1, - "balance start", "\n" + { do_balance, -1, + "balance start", "[-w|--wait] \n" "Synonym for \"btrfs filesystem balance\"." }, { do_balance_progress, -1, diff --git a/btrfs_cmds.c b/btrfs_cmds.c index b1631a0..070b8a9 100644 --- a/btrfs_cmds.c +++ b/btrfs_cmds.c @@ -754,12 +754,41 @@ int do_add_volume(int nargs, char **args) } +const struct option balance_options[] = { + { "wait", 0, NULL, 'w' }, + { NULL, 0, NULL, 0 } +}; + int do_balance(int argc, char **argv) { - int fdmnt, ret=0; + int background = 1; struct btrfs_ioctl_vol_args args; - char *path = argv[1]; + char *path; + int ttyfd; + + optind = 1; + while(1) { + int c = getopt_long(argc, argv, "w", balance_options, NULL); + if (c < 0) + break; + switch(c) { + case 'w': + background = 0; + break; + default: + fprintf(stderr, "Invalid arguments for balance\n"); + free(argv); + return 1; + } + } + + if(optind >= argc) { + fprintf(stderr, "No filesystem path given for balance\n"); + return 1; + } + + path = argv[optind]; fdmnt = open_file_or_dir(path); if (fdmnt < 0) { @@ -767,6 +796,25 @@ int do_balance(int argc, char **argv) return 12; } + if (background) { + int pid = fork(); + if (pid == 0) { + /* We're in the child, and can run in the background */ + ttyfd = open("/dev/tty", O_RDWR); + if (ttyfd > 0) + ioctl(ttyfd, TIOCNOTTY, 0); + /* Fall through to the BTRFS_IOC_BALANCE ioctl */ + } else if (pid > 0) { + /* We're in the parent, and the fork succeeded */ + printf("Background balance started\n"); + return 0; + } else { + /* We're in the parent, and the fork failed */ + fprintf(stderr, "ERROR: can't start background process -- %s\n", + strerror(errno)); + } + } + memset(&args, 0, sizeof(args)); ret = ioctl(fdmnt, BTRFS_IOC_BALANCE, &args); close(fdmnt); diff --git a/man/btrfs.8.in b/man/btrfs.8.in index 9c6bb69..77558fa 100644 --- a/man/btrfs.8.in +++ b/man/btrfs.8.in @@ -21,11 +21,11 @@ btrfs \- control a btrfs filesystem .PP \fBbtrfs\fP \fBfilesystem resize\fP\fI [+/\-][gkm]|max \fP .PP -\fBbtrfs\fP \fBfilesystem balance\fP\fI \fP +\fBbtrfs\fP \fBfilesystem balance\fP [\fB-w\fP|\fB--wait\fP] \fI\fP .PP \fBbtrfs\fP \fBdevice scan\fP\fI [ [..]]\fP .PP -\fBbtrfs\fP \fBbalance start\fP\fI \fP +\fBbtrfs\fP \fBbalance start\fP [\fB-w\fP|\fB--wait\fP] \fI\fP .PP \fBbtrfs\fP \fBbalance progress\fP [\fB-m\fP|\fB--monitor\fP] \fI\fP .PP @@ -149,11 +149,13 @@ Show the btrfs filesystem with some additional info. If no UUID or label is passed, \fBbtrfs\fR show info of all the btrfs filesystem. .TP -\fBbalance start\fR \fI\fR +\fBdevice balance\fR [\fB-w\fP|\fB--wait\fP] \fI\fR .TP -\fBfilesystem balance\fR \fI\fR -Balance the chunks of the filesystem identified by \fI\fR -across the devices. +\fBbalance start\fR [\fB-w\fP|\fB--wait\fP] \fI\fR + +Balance the chunks of the filesystem identified by \fI\fR across +the devices. The process runs in the background. Use \fB--wait\fP to +wait in the foreground for completion of the balance. .TP \fBdevice add\fR\fI [..] \fR