The branch main has been updated by des: URL: https://cgit.FreeBSD.org/src/commit/?id=a678e87f5533521f6dec1a4e85c3decb1c3b6584
commit a678e87f5533521f6dec1a4e85c3decb1c3b6584 Author: Dag-Erling Smørgrav <[email protected]> AuthorDate: 2025-12-17 22:38:11 +0000 Commit: Dag-Erling Smørgrav <[email protected]> CommitDate: 2025-12-17 22:40:59 +0000 unionfs: Support renaming symbolic links This adds support for renaming a symbolic link found on the lower fs, which necessitates copying it to the upper fs, as well as basic tests. MFC after: 1 week Sponsored by: Klara, Inc. Sponsored by: NetApp, Inc. Reviewed by: olce, siderop1_netapp.com, jah Differential Revision: https://reviews.freebsd.org/D54229 --- etc/mtree/BSD.tests.dist | 2 + sys/fs/unionfs/union.h | 1 + sys/fs/unionfs/union_subr.c | 168 +++++++++++++++++++++++++++++++++++ sys/fs/unionfs/union_vnops.c | 10 +++ tests/sys/fs/Makefile | 1 + tests/sys/fs/unionfs/Makefile | 8 ++ tests/sys/fs/unionfs/unionfs_test.sh | 165 ++++++++++++++++++++++++++++++++++ 7 files changed, 355 insertions(+) diff --git a/etc/mtree/BSD.tests.dist b/etc/mtree/BSD.tests.dist index e2b8c8ede325..5d004964e4e2 100644 --- a/etc/mtree/BSD.tests.dist +++ b/etc/mtree/BSD.tests.dist @@ -826,6 +826,8 @@ .. tmpfs .. + unionfs + .. .. geom class diff --git a/sys/fs/unionfs/union.h b/sys/fs/unionfs/union.h index 0bd1894a2195..fe5a578ef4dc 100644 --- a/sys/fs/unionfs/union.h +++ b/sys/fs/unionfs/union.h @@ -142,6 +142,7 @@ void unionfs_tryrem_node_status(struct unionfs_node *, int unionfs_check_rmdir(struct vnode *, struct ucred *, struct thread *td); int unionfs_copyfile(struct vnode *, int, struct ucred *, struct thread *); +int unionfs_copylink(struct vnode *, struct ucred *, struct thread *); void unionfs_create_uppervattr_core(struct unionfs_mount *, struct vattr *, struct vattr *, struct thread *); int unionfs_create_uppervattr(struct unionfs_mount *, struct vnode *, diff --git a/sys/fs/unionfs/union_subr.c b/sys/fs/unionfs/union_subr.c index b6d6db60ca3d..0774d4fb69be 100644 --- a/sys/fs/unionfs/union_subr.c +++ b/sys/fs/unionfs/union_subr.c @@ -1516,6 +1516,174 @@ unionfs_copyfile_cleanup: return (error); } +/* + * Create a new symbolic link on upper. + * + * If an error is returned, *vpp will be invalid, otherwise it will hold a + * locked, referenced and opened vnode. + * + * unp is never updated. + */ +static int +unionfs_vn_symlink_on_upper(struct vnode **vpp, struct vnode *udvp, + struct vnode *vp, struct vattr *uvap, const char *target, + struct thread *td) +{ + struct unionfs_mount *ump; + struct unionfs_node *unp; + struct vnode *uvp; + struct vnode *lvp; + struct ucred *cred; + struct vattr lva; + struct nameidata nd; + int error; + + ASSERT_VOP_ELOCKED(vp, __func__); + unp = VTOUNIONFS(vp); + ump = MOUNTTOUNIONFSMOUNT(UNIONFSTOV(unp)->v_mount); + uvp = NULL; + lvp = unp->un_lowervp; + cred = td->td_ucred; + error = 0; + + if ((error = VOP_GETATTR(lvp, &lva, cred)) != 0) + return (error); + unionfs_create_uppervattr_core(ump, &lva, uvap, td); + + if (unp->un_path == NULL) + panic("%s: NULL un_path", __func__); + + nd.ni_cnd.cn_namelen = unp->un_pathlen; + nd.ni_cnd.cn_pnbuf = unp->un_path; + nd.ni_cnd.cn_nameiop = CREATE; + nd.ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF | ISLASTCN; + nd.ni_cnd.cn_lkflags = LK_EXCLUSIVE; + nd.ni_cnd.cn_cred = cred; + nd.ni_cnd.cn_nameptr = nd.ni_cnd.cn_pnbuf; + NDPREINIT(&nd); + + vref(udvp); + VOP_UNLOCK(vp); + if ((error = vfs_relookup(udvp, &uvp, &nd.ni_cnd, false)) != 0) { + vrele(udvp); + return (error); + } + + if (uvp != NULL) { + if (uvp == udvp) + vrele(uvp); + else + vput(uvp); + error = EEXIST; + goto unionfs_vn_symlink_on_upper_cleanup; + } + + error = VOP_SYMLINK(udvp, &uvp, &nd.ni_cnd, uvap, target); + if (error == 0) + *vpp = uvp; + +unionfs_vn_symlink_on_upper_cleanup: + vput(udvp); + return (error); +} + +/* + * Copy symbolic link from lower to upper. + * + * vp is a unionfs vnode that should be locked on entry and will be + * locked on return. + * + * If no error returned, unp will be updated. + */ +int +unionfs_copylink(struct vnode *vp, struct ucred *cred, + struct thread *td) +{ + struct unionfs_node *unp; + struct unionfs_node *dunp; + struct mount *mp; + struct vnode *udvp; + struct vnode *lvp; + struct vnode *uvp; + struct vattr uva; + char *buf = NULL; + struct uio uio; + struct iovec iov; + int error; + + ASSERT_VOP_ELOCKED(vp, __func__); + unp = VTOUNIONFS(vp); + lvp = unp->un_lowervp; + uvp = NULL; + + if ((UNIONFSTOV(unp)->v_mount->mnt_flag & MNT_RDONLY)) + return (EROFS); + if (unp->un_dvp == NULL) + return (EINVAL); + if (unp->un_uppervp != NULL) + return (EEXIST); + + udvp = NULL; + VI_LOCK(unp->un_dvp); + dunp = VTOUNIONFS(unp->un_dvp); + if (dunp != NULL) + udvp = dunp->un_uppervp; + VI_UNLOCK(unp->un_dvp); + + if (udvp == NULL) + return (EROFS); + if ((udvp->v_mount->mnt_flag & MNT_RDONLY)) + return (EROFS); + ASSERT_VOP_UNLOCKED(udvp, __func__); + + error = unionfs_set_in_progress_flag(vp, UNIONFS_COPY_IN_PROGRESS); + if (error == EJUSTRETURN) + return (0); + else if (error != 0) + return (error); + + uio.uio_td = td; + uio.uio_segflg = UIO_SYSSPACE; + uio.uio_offset = 0; + uio.uio_iov = &iov; + uio.uio_iovcnt = 1; + iov.iov_base = buf = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); + uio.uio_resid = iov.iov_len = MAXPATHLEN; + uio.uio_rw = UIO_READ; + + if ((error = VOP_READLINK(lvp, &uio, cred)) != 0) + goto unionfs_copylink_cleanup; + buf[iov.iov_len - uio.uio_resid] = '\0'; + if ((error = vn_start_write(udvp, &mp, V_WAIT | V_PCATCH)) != 0) + goto unionfs_copylink_cleanup; + error = unionfs_vn_symlink_on_upper(&uvp, udvp, vp, &uva, buf, td); + vn_finished_write(mp); + if (error != 0) { + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); + goto unionfs_copylink_cleanup; + } + + vn_lock_pair(vp, false, LK_EXCLUSIVE, uvp, true, LK_EXCLUSIVE); + unp = VTOUNIONFS(vp); + if (unp == NULL) { + error = ENOENT; + goto unionfs_copylink_cleanup; + } + + if (error == 0) { + /* Reset the attributes. Ignore errors. */ + uva.va_type = VNON; + VOP_SETATTR(uvp, &uva, cred); + unionfs_node_update(unp, uvp, td); + } + +unionfs_copylink_cleanup: + if (buf != NULL) + free(buf, M_TEMP); + unionfs_clear_in_progress_flag(vp, UNIONFS_COPY_IN_PROGRESS); + return (error); +} + /* * Determine if the unionfs view of a directory is empty such that * an rmdir operation can be permitted. diff --git a/sys/fs/unionfs/union_vnops.c b/sys/fs/unionfs/union_vnops.c index 060863866fcf..cefd591a9a0f 100644 --- a/sys/fs/unionfs/union_vnops.c +++ b/sys/fs/unionfs/union_vnops.c @@ -1478,6 +1478,13 @@ unionfs_rename(struct vop_rename_args *ap) */ VOP_UNLOCK(tdvp); relock_tdvp = true; + } else if (fvp->v_type == VLNK) { + /* + * The symbolic link case is similar to the + * regular file case. + */ + VOP_UNLOCK(tdvp); + relock_tdvp = true; } else if (fvp->v_type == VDIR && tdvp != fdvp) { /* * For directories, unionfs_mkshadowdir() will expect @@ -1501,6 +1508,9 @@ unionfs_rename(struct vop_rename_args *ap) case VREG: error = unionfs_copyfile(fvp, 1, fcnp->cn_cred, td); break; + case VLNK: + error = unionfs_copylink(fvp, fcnp->cn_cred, td); + break; case VDIR: error = unionfs_mkshadowdir(fdvp, fvp, fcnp, td); break; diff --git a/tests/sys/fs/Makefile b/tests/sys/fs/Makefile index e36a97d2335a..254394f43714 100644 --- a/tests/sys/fs/Makefile +++ b/tests/sys/fs/Makefile @@ -14,6 +14,7 @@ TESTS_SUBDIRS+= fusefs .endif TESTS_SUBDIRS+= tarfs TESTS_SUBDIRS+= tmpfs +TESTS_SUBDIRS+= unionfs ${PACKAGE}FILES+= h_funcs.subr ${PACKAGE}FILESDIR= ${TESTSDIR} diff --git a/tests/sys/fs/unionfs/Makefile b/tests/sys/fs/unionfs/Makefile new file mode 100644 index 000000000000..da25fcefb473 --- /dev/null +++ b/tests/sys/fs/unionfs/Makefile @@ -0,0 +1,8 @@ +PACKAGE= tests + +TESTSDIR= ${TESTSBASE}/sys/fs/unionfs +BINDIR= ${TESTSDIR} + +ATF_TESTS_SH+= unionfs_test + +.include <bsd.test.mk> diff --git a/tests/sys/fs/unionfs/unionfs_test.sh b/tests/sys/fs/unionfs/unionfs_test.sh new file mode 100644 index 000000000000..ee8a9bae19e7 --- /dev/null +++ b/tests/sys/fs/unionfs/unionfs_test.sh @@ -0,0 +1,165 @@ +#!/bin/sh +#- +# SPDX-License-Identifier: BSD-2-Clause +# +# Copyright (c) 2025 Klara, Inc. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +# SUCH DAMAGE. +# + +# Create and mount a filesystem for use in our tests +unionfs_mkfs() { + local name=$1 + local size=${2:-1} + # Create mountpoint + atf_check mkdir ${name} + # Create filesystem image + atf_check -e ignore dd if=/dev/zero of=${name}.img bs=1m count=${size} + echo ${name} >>imgs + # Create memory disk + atf_check -o save:${name}.md mdconfig ${name}.img + md=$(cat ${name}.md) + echo ${md} >>mds + # Format and mount filesystem + atf_check -o ignore newfs /dev/${md} + atf_check mount /dev/${md} ${name} + echo ${name} >>mounts +} + +# Mount a unionfs +unionfs_mount() { + local upper=$1 + local lower=$2 + # Mount upper over lower + atf_check mount -t unionfs ${upper} ${lower} + echo ${lower} >>mounts +} + +# Clean up after a test +unionfs_cleanup() { + # Unmount filesystems + if [ -f mounts ]; then + tail -r mounts | while read mount; do + umount ${mount} || true + done + fi + # Destroy memory disks + if [ -f mds ]; then + tail -r mds | while read md; do + mdconfig -d -u ${md} || true + done + fi + # Delete filesystem images and mountpoints + if [ -f imgs ]; then + tail -r imgs | while read name; do + rm -f ${name}.img || true + rmdir ${name} || true + done + fi +} + +atf_test_case unionfs_basic cleanup +unionfs_basic_head() { + atf_set "descr" "Basic function test" + atf_set "require.user" "root" + atf_set "require.kmods" "unionfs" +} +unionfs_basic_body() { + # Create upper and lower + unionfs_mkfs upper + unionfs_mkfs lower + # Mount upper over lower + unionfs_mount upper lower + # Create object on unionfs + atf_check touch upper/file + atf_check mkdir upper/dir + atf_check touch lower/dir/file + # Verify that objects were created on upper + atf_check test -f lower/file + atf_check test -d lower/dir + atf_check test -f upper/dir/file +} +unionfs_basic_cleanup() { + unionfs_cleanup +} + +atf_test_case unionfs_exec cleanup +unionfs_exec_head() { + atf_set "descr" "Test executing programs" + atf_set "require.user" "root" + atf_set "require.kmods" "unionfs" +} +unionfs_exec_body() { + # Create upper and copy a binary to it + unionfs_mkfs upper + atf_check cp -p /usr/bin/true upper/upper + # Create lower and copy a binary to it + unionfs_mkfs lower + atf_check cp -p /usr/bin/true lower/lower + # Mount upper over lower + unionfs_mount upper lower + # Execute both binaries + atf_check lower/lower + atf_check lower/upper +} +unionfs_exec_cleanup() { + unionfs_cleanup +} + +atf_test_case unionfs_rename cleanup +unionfs_rename_head() { + atf_set "descr" "Test renaming objects on lower" + atf_set "require.user" "root" + atf_set "require.kmods" "unionfs" +} +unionfs_rename_body() { + # Create upper and lower + unionfs_mkfs upper + unionfs_mkfs lower + # Create objects on lower + atf_check touch lower/file + atf_check mkdir lower/dir + atf_check ln -s dead lower/link + # Mount upper over lower + unionfs_mount upper lower + # Rename objects + atf_check mv lower/file lower/newfile + atf_check mv lower/dir lower/newdir + atf_check mv lower/link lower/newlink + # Verify that old names no longer exist + atf_check test ! -f lower/file + atf_check test ! -d lower/dir + atf_check test ! -L lower/link + # Verify that new names exist on upper + atf_check test -f upper/newfile + atf_check test -d upper/newdir + atf_check test -L upper/newlink +} +unionfs_rename_cleanup() { + unionfs_cleanup +} + +atf_init_test_cases() { + atf_add_test_case unionfs_basic + atf_add_test_case unionfs_exec + atf_add_test_case unionfs_rename +}
