The branch main has been updated by rmacklem:
URL:
https://cgit.FreeBSD.org/src/commit/?id=37b2cb5ecb0fb1b1f5a98ff4c08b61b8c05ec1d7
commit 37b2cb5ecb0fb1b1f5a98ff4c08b61b8c05ec1d7
Author: Rick Macklem <rmack...@freebsd.org>
AuthorDate: 2025-08-08 00:52:23 +0000
Commit: Rick Macklem <rmack...@freebsd.org>
CommitDate: 2025-08-08 00:52:23 +0000
vfs: Add support for file cloning to VOP_COPY_FILE_RANGE
NFSv4 has a separate CLONE operation from COPY with
a couple of semantics differences. Unlike COPY, CLONE
must complete the "copy on write" and cannot return
partially copied. It also is required to use offsets (and
the length if not to EOF) that are aligned to a buffer
boundary.
Since VOP_COPY_FILE_RANGE() can already do "copy on write"
for file systems that support it, such as ZFS with block
cloning enabled, all this patch does is add a flag called
COPY_FILE_RANGE_CLONE so that it will conform to the
rule that it must do a "copy on write" to completion.
The patch also adds a new pathconf(2) name _PC_CLONE_BLKSIZE,
which acquires the blocksize requirement for cloning and
returns 0 for file systems that do not support the
"copy on write" feature. (This is needed for the NFSv4.2
clone_blksize attribute.)
This patch will allow the implementation of CLONE
for NFSv4.2.
Reviewed by: asomers
Differential Revision: https://reviews.freebsd.org/D51808
---
sys/fs/fuse/fuse_vnops.c | 3 +++
sys/kern/vfs_default.c | 1 +
sys/kern/vfs_syscalls.c | 2 +-
sys/kern/vfs_vnops.c | 5 +++++
sys/sys/unistd.h | 1 +
sys/sys/vnode.h | 17 +++++++++++++----
6 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/sys/fs/fuse/fuse_vnops.c b/sys/fs/fuse/fuse_vnops.c
index b90ce60ec664..b782146b7278 100644
--- a/sys/fs/fuse/fuse_vnops.c
+++ b/sys/fs/fuse/fuse_vnops.c
@@ -877,6 +877,9 @@ fuse_vnop_copy_file_range(struct vop_copy_file_range_args
*ap)
pid_t pid;
int err;
+ if ((ap->a_flags & COPY_FILE_RANGE_CLONE) != 0)
+ return (EXTERROR(ENOSYS, "Cannot clone"));
+
if (mp == NULL || mp != vnode_mount(outvp))
return (EXTERROR(ENOSYS, "Mount points do not match"));
diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c
index fd6202a1424c..85f67731e1cc 100644
--- a/sys/kern/vfs_default.c
+++ b/sys/kern/vfs_default.c
@@ -457,6 +457,7 @@ vop_stdpathconf(struct vop_pathconf_args *ap)
case _PC_NAMEDATTR_ENABLED:
case _PC_HAS_NAMEDATTR:
case _PC_HAS_HIDDENSYSTEM:
+ case _PC_CLONE_BLKSIZE:
*ap->a_retval = 0;
return (0);
default:
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index 9704e9c160a8..c64618036733 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -5058,7 +5058,7 @@ kern_copy_file_range(struct thread *td, int infd, off_t
*inoffp, int outfd,
error = 0;
retlen = 0;
- if (flags != 0) {
+ if ((flags & ~COPY_FILE_RANGE_USERFLAGS) != 0) {
error = EINVAL;
goto out;
}
diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index 6451c9e07a60..93f87ddae4de 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -3443,6 +3443,11 @@ vn_generic_copy_file_range(struct vnode *invp, off_t
*inoffp,
interrupted = 0;
dat = NULL;
+ if ((flags & COPY_FILE_RANGE_CLONE) != 0) {
+ error = ENOSYS;
+ goto out;
+ }
+
error = vn_lock(invp, LK_SHARED);
if (error != 0)
goto out;
diff --git a/sys/sys/unistd.h b/sys/sys/unistd.h
index 85ed93fd359d..7ab2f021e408 100644
--- a/sys/sys/unistd.h
+++ b/sys/sys/unistd.h
@@ -159,6 +159,7 @@
#define _PC_XATTR_ENABLED _PC_NAMEDATTR_ENABLED /* Solaris
Compatible */
#define _PC_XATTR_EXISTS _PC_HAS_NAMEDATTR /* Solaris
Compatible */
#define _PC_HAS_HIDDENSYSTEM 68
+#define _PC_CLONE_BLKSIZE 69
#endif
/* From OpenSolaris, used by SEEK_DATA/SEEK_HOLE. */
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 074769d55c2d..8080e9edd8c3 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -397,8 +397,21 @@ struct vattr {
*/
#define VLKTIMEOUT (hz / 20 + 1)
+/* copy_file_range flags */
+#define COPY_FILE_RANGE_KFLAGS 0xff000000
+
+/*
+ * copy_file_range flags visible to user space.
+ * Allocate high bits first, to try and avoid conflicting with Linux.
+ */
+#define COPY_FILE_RANGE_CLONE 0x00800000 /* Require
cloning. */
+#define COPY_FILE_RANGE_USERFLAGS (COPY_FILE_RANGE_CLONE)
+
#ifdef _KERNEL
+/* copy_file_range flags only usable in the kernel */
+#define COPY_FILE_RANGE_TIMEO1SEC 0x01000000 /* Return after
1sec. */
+
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_VNODE);
#endif
@@ -621,10 +634,6 @@ typedef void vop_getpages_iodone_t(void *, vm_page_t *,
int, int);
#define VN_OPEN_INVFS 0x00000008
#define VN_OPEN_WANTIOCTLCAPS 0x00000010
-/* copy_file_range kernel flags */
-#define COPY_FILE_RANGE_KFLAGS 0xff000000
-#define COPY_FILE_RANGE_TIMEO1SEC 0x01000000 /* Return after
1sec. */
-
/*
* Public vnode manipulation functions.
*/
