From patchwork Sat Apr 30 14:23:57 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugo Mills X-Patchwork-Id: 743672 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 p3UEOUAo020154 for ; Sat, 30 Apr 2011 14:24:30 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756911Ab1D3OY2 (ORCPT ); Sat, 30 Apr 2011 10:24:28 -0400 Received: from frost.carfax.org.uk ([212.13.194.111]:4422 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754994Ab1D3OYL (ORCPT ); Sat, 30 Apr 2011 10:24:11 -0400 Received: from ruthven.carfax.org.uk ([10.0.0.10]) by frost.carfax.org.uk with esmtp (Exim 4.69) (envelope-from ) id 1QGB5Y-0005h5-Gh; Sat, 30 Apr 2011 14:24:07 +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 1QGB5Y-0007ay-8i; Sat, 30 Apr 2011 15:24:04 +0100 From: Hugo Mills To: Btrfs mailing list , Chris Mason , David Sterba Subject: [PATCH v6 2/8] btrfs: Cancel filesystem balance Date: Sat, 30 Apr 2011 15:23:57 +0100 Message-Id: <1304173443-29159-3-git-send-email-hugo@carfax.org.uk> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1304173443-29159-1-git-send-email-hugo@carfax.org.uk> References: <1304173443-29159-1-git-send-email-hugo@carfax.org.uk> X-frost.carfax.org.uk-Spam-Score: -0.0 (/) X-frost.carfax.org.uk-Spam-Report: Spam detection software, running on the system "spamd2.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 adds an ioctl for cancelling a btrfs balance operation mid-flight. The ioctl simply sets a flag, and the operation terminates after the current block group move has completed. Signed-off-by: Hugo Mills --- fs/btrfs/ctree.h | 1 + fs/btrfs/ioctl.c | 28 ++++++++++++++++++++++++++++ fs/btrfs/ioctl.h | 1 + fs/btrfs/volumes.c | 7 ++++++- 4 files changed, 36 insertions(+), 1 deletions(-) [...] 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]); Sat, 30 Apr 2011 14:24:30 +0000 (UTC) This patch adds an ioctl for cancelling a btrfs balance operation mid-flight. The ioctl simply sets a flag, and the operation terminates after the current block group move has completed. Signed-off-by: Hugo Mills --- fs/btrfs/ctree.h | 1 + fs/btrfs/ioctl.c | 28 ++++++++++++++++++++++++++++ fs/btrfs/ioctl.h | 1 + fs/btrfs/volumes.c | 7 ++++++- 4 files changed, 36 insertions(+), 1 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index ad15eb7..fefd67a 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -869,6 +869,7 @@ struct btrfs_block_group_cache { struct btrfs_balance_info { u32 expected; u32 completed; + int cancel_pending; }; struct reloc_control; diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 899ed91..4044ad3 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2497,6 +2497,32 @@ error: return ret; } +/* + * Cancel a running balance operation + */ +long btrfs_ioctl_balance_cancel(struct btrfs_fs_info *fs_info) +{ + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + spin_lock(&fs_info->balance_info_lock); + if (!fs_info->balance_info) { + err = -EINVAL; + goto error; + } + if (fs_info->balance_info->cancel_pending) { + err = -ECANCELED; + goto error; + } + fs_info->balance_info->cancel_pending = 1; + +error: + spin_unlock(&fs_info->balance_info_lock); + return err; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2540,6 +2566,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_balance(root->fs_info->dev_root); case BTRFS_IOC_BALANCE_PROGRESS: return btrfs_ioctl_balance_progress(root->fs_info, argp); + case BTRFS_IOC_BALANCE_CANCEL: + return btrfs_ioctl_balance_cancel(root->fs_info); case BTRFS_IOC_CLONE: return btrfs_ioctl_clone(file, arg, 0, 0, 0); case BTRFS_IOC_CLONE_RANGE: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 7c37c6b..2c49add 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -210,4 +210,5 @@ struct btrfs_ioctl_balance_progress { #define BTRFS_IOC_SUBVOL_SETFLAGS _IOW(BTRFS_IOCTL_MAGIC, 26, __u64) #define BTRFS_IOC_BALANCE_PROGRESS _IOR(BTRFS_IOCTL_MAGIC, 27, \ struct btrfs_ioctl_balance_progress) +#define BTRFS_IOC_BALANCE_CANCEL _IO(BTRFS_IOCTL_MAGIC, 28) #endif diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 8ab70f3..07ff192 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2055,6 +2055,7 @@ int btrfs_balance(struct btrfs_root *dev_root) bal_info->expected = -1; /* One less than actually counted, because chunk 0 is special */ bal_info->completed = 0; + bal_info->cancel_pending = 0; spin_unlock(&dev_root->fs_info->balance_info_lock); /* step one make some room on all the devices */ @@ -2115,7 +2116,7 @@ int btrfs_balance(struct btrfs_root *dev_root) key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; - while (1) { + while (!bal_info->cancel_pending) { ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) goto error; @@ -2155,6 +2156,10 @@ int btrfs_balance(struct btrfs_root *dev_root) bal_info->completed, bal_info->expected); } ret = 0; + if (bal_info->cancel_pending) { + printk(KERN_INFO "btrfs: balance cancelled\n"); + ret = -EINTR; + } error: btrfs_free_path(path); spin_lock(&dev_root->fs_info->balance_info_lock);