From 896c14f97f700aec6565154f2451605d7c5ce3ed Mon Sep 17 00:00:00 2001 From: Wang Shilong Date: Tue, 7 Jan 2014 17:25:18 +0800 Subject: [PATCH] Btrfs: fix wrong send_in_progress accounting Steps to reproduce: # mkfs.btrfs -f /dev/sda8 # mount /dev/sda8 /mnt # btrfs sub snapshot -r /mnt /mnt/snap1 # btrfs sub snapshot -r /mnt /mnt/snap2 # btrfs send /mnt/snap1 -p /mnt/snap2 -f /mnt/1 # dmesg The problem is that we will sort clone roots(include @send_root), it might push @send_root before thus @send_root's @send_in_progress will be decreased twice. Cc: David Sterba Signed-off-by: Wang Shilong Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/send.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index bff0b1ac3be7..5b6978516461 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -4752,6 +4752,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) u32 i; u64 *clone_sources_tmp = NULL; int clone_sources_to_rollback = 0; + int sort_clone_roots = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -4942,6 +4943,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) sort(sctx->clone_roots, sctx->clone_roots_cnt, sizeof(*sctx->clone_roots), __clone_root_cmp_sort, NULL); + sort_clone_roots = 1; ret = send_subvol(sctx); if (ret < 0) @@ -4957,11 +4959,19 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) } out: - for (i = 0; sctx && i < clone_sources_to_rollback; i++) - btrfs_root_dec_send_in_progress(sctx->clone_roots[i].root); + if (sort_clone_roots) { + for (i = 0; i < sctx->clone_roots_cnt; i++) + btrfs_root_dec_send_in_progress( + sctx->clone_roots[i].root); + } else { + for (i = 0; sctx && i < clone_sources_to_rollback; i++) + btrfs_root_dec_send_in_progress( + sctx->clone_roots[i].root); + + btrfs_root_dec_send_in_progress(send_root); + } if (sctx && !IS_ERR_OR_NULL(sctx->parent_root)) btrfs_root_dec_send_in_progress(sctx->parent_root); - btrfs_root_dec_send_in_progress(send_root); kfree(arg); vfree(clone_sources_tmp);