From: Jeff Mahoney Date: Tue, 9 Aug 2016 02:08:06 +0000 (-0400) Subject: btrfs: waiting on qgroup rescan should not always be interruptible X-Git-Tag: android-x86-6.0-r1~1^2~2^2~28 X-Git-Url: http://git.osdn.net/view?p=android-x86%2Fkernel.git;a=commitdiff_plain;h=f31d48a091877f7580c0c6aa70e3d35d9b6e8625 btrfs: waiting on qgroup rescan should not always be interruptible commit d06f23d6a947c9abae41dc46be69a56baf36f436 upstream. We wait on qgroup rescan completion in three places: file system shutdown, the quota disable ioctl, and the rescan wait ioctl. If the user sends a signal while we're waiting, we continue happily along. This is expected behavior for the rescan wait ioctl. It's racy in the shutdown path but mostly works due to other unrelated synchronization points. In the quota disable path, it Oopses the kernel pretty much immediately. Signed-off-by: Jeff Mahoney Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Chris Mason Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 41fb43183406..10bc556ddb3d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3811,7 +3811,7 @@ void close_ctree(struct btrfs_root *root) smp_mb(); /* wait for the qgroup rescan worker to stop */ - btrfs_qgroup_wait_for_completion(fs_info); + btrfs_qgroup_wait_for_completion(fs_info, false); /* wait for the uuid_scan task to finish */ down(&fs_info->uuid_tree_rescan_sem); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index bfcd87ee8ff5..65f30b3b04f9 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -5121,7 +5121,7 @@ static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) if (!capable(CAP_SYS_ADMIN)) return -EPERM; - return btrfs_qgroup_wait_for_completion(root->fs_info); + return btrfs_qgroup_wait_for_completion(root->fs_info, true); } static long _btrfs_ioctl_set_received_subvol(struct file *file, diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 5279fdae7142..d7829f5ebaf5 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -995,7 +995,7 @@ int btrfs_quota_disable(struct btrfs_trans_handle *trans, goto out; fs_info->quota_enabled = 0; fs_info->pending_quota_state = 0; - btrfs_qgroup_wait_for_completion(fs_info); + btrfs_qgroup_wait_for_completion(fs_info, false); spin_lock(&fs_info->qgroup_lock); quota_root = fs_info->quota_root; fs_info->quota_root = NULL; @@ -2467,7 +2467,8 @@ btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info) return 0; } -int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info) +int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, + bool interruptible) { int running; int ret = 0; @@ -2478,9 +2479,14 @@ int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info) spin_unlock(&fs_info->qgroup_lock); mutex_unlock(&fs_info->qgroup_rescan_lock); - if (running) + if (!running) + return 0; + + if (interruptible) ret = wait_for_completion_interruptible( &fs_info->qgroup_rescan_completion); + else + wait_for_completion(&fs_info->qgroup_rescan_completion); return ret; } diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index ecb2c143ef75..3d73e4c9c7df 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -46,7 +46,8 @@ int btrfs_quota_disable(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info); int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info); void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info); -int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info); +int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, + bool interruptible); int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 src, u64 dst); int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,