From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:18111 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751566AbcEJOJg (ORCPT ); Tue, 10 May 2016 10:09:36 -0400 From: Anand Jain To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz, yauhen.kharuzhy@zavadatar.com Subject: [PATCH 1/1] btrfs: introduce helper functions to perform hot replace Date: Tue, 10 May 2016 22:09:20 +0800 Message-Id: <1462889372-5274-3-git-send-email-anand.jain@oracle.com> In-Reply-To: <1462889372-5274-1-git-send-email-anand.jain@oracle.com> References: <1462889372-5274-1-git-send-email-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Anand Jain Hot replace / auto replace is important volume manager feature and is critical to the data center operations, so that the degraded volume can be brought back to a healthy state at the earliest and without manual intervention. This modifies the existing replace code to suite the need of auto replace, in the long run I hope both the codes to be merged. Signed-off-by: Anand Jain Tested-by: Austin S. Hemmelgarn --- fs/btrfs/dev-replace.c | 43 +++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/dev-replace.h | 1 + 2 files changed, 44 insertions(+) diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c index 5ec7fa860391..83af64907547 100644 --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -937,3 +937,46 @@ void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) &fs_info->fs_state)); } } + +int btrfs_auto_replace_start(struct btrfs_root *root, u64 src_devid) +{ + int ret; + char *tgt_path; + struct btrfs_fs_info *fs_info = root->fs_info; + + if (!src_devid) + return -EINVAL; + + if (fs_info->sb->s_flags & MS_RDONLY) + return -EROFS; + + btrfs_dev_replace_lock(&fs_info->dev_replace, 0); + if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { + btrfs_dev_replace_unlock(&fs_info->dev_replace, 0); + return -EBUSY; + } + btrfs_dev_replace_unlock(&fs_info->dev_replace, 0); + + if (btrfs_get_spare_device(&tgt_path)) { + btrfs_info_rl(root->fs_info, + "No spare device found/configured in the kernel"); + return -EINVAL; + } + + if (atomic_xchg( + &root->fs_info->mutually_exclusive_operation_running, 1)) { + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + } else { + ret = btrfs_dev_replace_start(root, tgt_path, src_devid, NULL, + BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS); + atomic_set( + &root->fs_info->mutually_exclusive_operation_running, 0); + } + + if (ret) + btrfs_put_spare_device(tgt_path); + + kfree(tgt_path); + + return ret; +} diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h index e922b42d91df..54b0812c8ba4 100644 --- a/fs/btrfs/dev-replace.h +++ b/fs/btrfs/dev-replace.h @@ -46,4 +46,5 @@ static inline void btrfs_dev_replace_stats_inc(atomic64_t *stat_value) { atomic64_inc(stat_value); } +int btrfs_auto_replace_start(struct btrfs_root *root, u64 src_devid); #endif -- 2.7.0