git: c52b5d16ccf2 - main - Remove a partial UFS/FFS snapshot if it fails to build successfully.

The branch main has been updated by mckusick:

URL: https://cgit.FreeBSD.org/src/commit/?id=c52b5d16ccf29ad0e999a1f5f813ed6472aa3771

commit c52b5d16ccf29ad0e999a1f5f813ed6472aa3771
Author:     Kirk McKusick <mckusick@FreeBSD.org>
AuthorDate: 2023-08-09 23:43:41 +0000
Commit:     Kirk McKusick <mckusick@FreeBSD.org>
CommitDate: 2023-08-09 23:44:24 +0000

    Remove a partial UFS/FFS snapshot if it fails to build successfully.
    
    When taking a UFS/FFS snapshot, it may not succeed for example if the
    filesystem is too full to hold it. When a snapshot is unable to be
    successfully taken, the partial snapshot should be removed.
    
    Reported-by:  Peter Holm
    Tested-by:    Peter Holm
    MFC-after:    1 week
    Sponsored-by: The FreeBSD Foundation
---
 sys/ufs/ffs/ffs_snapshot.c | 31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/sys/ufs/ffs/ffs_snapshot.c b/sys/ufs/ffs/ffs_snapshot.c
index 26eecfcc5875..6a3329078817 100644
--- a/sys/ufs/ffs/ffs_snapshot.c
+++ b/sys/ufs/ffs/ffs_snapshot.c
@@ -851,7 +851,6 @@ done:
 	free(copy_fs, M_UFSMNT);
 	copy_fs = NULL;
 out:
-	NDFREE_PNBUF(&nd);
 	if (saved_nice > 0) {
 		struct proc *p;
 
@@ -869,14 +868,30 @@ out:
 	MNT_ILOCK(mp);
 	mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA);
 	MNT_IUNLOCK(mp);
-	if (error)
-		(void) ffs_truncate(vp, (off_t)0, 0, NOCRED);
-	(void) ffs_syncvnode(vp, MNT_WAIT, 0);
-	if (error)
-		vput(vp);
-	else
-		VOP_UNLOCK(vp);
+	NDFREE_PNBUF(&nd);
 	vrele(nd.ni_dvp);
+	if (error == 0) {
+		(void) ffs_syncvnode(vp, MNT_WAIT, 0);
+		VOP_UNLOCK(vp);
+	} else if (VN_IS_DOOMED(vp)) {
+		vput(vp);
+	} else {
+		int rmerr;
+
+		/* Remove snapshot as its creation has failed. */
+		vput(vp);
+		NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF, UIO_SYSSPACE,
+		    snapfile);
+		if ((rmerr = namei(&nd)) != 0 ||
+		    (rmerr = VOP_REMOVE(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd)) != 0)
+			printf("Delete of %s failed with error %d\n",
+			    nd.ni_dirp, rmerr);
+		NDFREE_PNBUF(&nd);
+		if (nd.ni_dvp != NULL)
+			vput(nd.ni_dvp);
+		if (nd.ni_vp != NULL)
+			vput(nd.ni_vp);
+	}
 	vn_finished_write(wrtmp);
 	process_deferred_inactive(mp);
 	return (error);