git: 6b8f0b47776b - main - fusefs: Upgrade FUSE protocol to version 7.35.

The branch main has been updated by asomers:

URL: https://cgit.FreeBSD.org/src/commit/?id=6b8f0b47776bac6e4d2b7e4cfcecea485e4d91f9

commit 6b8f0b47776bac6e4d2b7e4cfcecea485e4d91f9
Author:     Claudiu I. Palincas <mscotty@protonmail.ch>
AuthorDate: 2025-06-27 16:33:37 +0000
Commit:     Alan Somers <asomers@FreeBSD.org>
CommitDate: 2025-07-03 16:23:10 +0000

    fusefs: Upgrade FUSE protocol to version 7.35.
    
    Upgrade the FUSE API from protocol 7.33 to 7.35.
    Add support for FOPEN_NOFLUSH, introduced in 7.35.
    
    Also, reduce diffs vis-a-vis upstream by factoring out an ioctl type, a
    change missed in d5e3cf41e89.
    
    Signed-off-by:  Claudiu I. Palincas <mscotty@protonmail.ch>
    Reviewed by:    asomers
    Pull Request:   https://github.com/freebsd/freebsd-src/pull/1744
---
 sys/fs/fuse/fuse_file.h      |  2 +-
 sys/fs/fuse/fuse_kernel.h    | 18 ++++++++++++++++--
 sys/fs/fuse/fuse_vnops.c     |  4 ++++
 tests/sys/fs/fusefs/flush.cc | 30 ++++++++++++++++++++++++++++++
 4 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/sys/fs/fuse/fuse_file.h b/sys/fs/fuse/fuse_file.h
index 2a90e66d1b23..232132473953 100644
--- a/sys/fs/fuse/fuse_file.h
+++ b/sys/fs/fuse/fuse_file.h
@@ -139,7 +139,7 @@ struct fuse_filehandle {
 
 	/*
 	 * flags returned by FUSE_OPEN
-	 * Supported flags: FOPEN_DIRECT_IO, FOPEN_KEEP_CACHE
+	 * Supported flags: FOPEN_DIRECT_IO, FOPEN_KEEP_CACHE, FOPEN_NOFLUSH
 	 * Unsupported:
 	 *     FOPEN_NONSEEKABLE: Adding support would require a new per-file
 	 *     or per-vnode attribute, which would have to be checked by
diff --git a/sys/fs/fuse/fuse_kernel.h b/sys/fs/fuse/fuse_kernel.h
index c95caf898ad8..942448b47365 100644
--- a/sys/fs/fuse/fuse_kernel.h
+++ b/sys/fs/fuse/fuse_kernel.h
@@ -182,6 +182,12 @@
  *  - add FUSE_OPEN_KILL_SUIDGID
  *  - extend fuse_setxattr_in, add FUSE_SETXATTR_EXT
  *  - add FUSE_SETXATTR_ACL_KILL_SGID
+ *
+ *  7.34
+ *  - add FUSE_SYNCFS
+ *
+ *  7.35
+ *  - add FOPEN_NOFLUSH
  */
 
 #ifndef _FUSE_FUSE_KERNEL_H
@@ -217,7 +223,7 @@
 #define FUSE_KERNEL_VERSION 7
 
 /** Minor version number of this interface */
-#define FUSE_KERNEL_MINOR_VERSION 33
+#define FUSE_KERNEL_MINOR_VERSION 35
 
 /** The node ID of the root inode */
 #define FUSE_ROOT_ID 1
@@ -288,12 +294,14 @@ struct fuse_file_lock {
  * FOPEN_NONSEEKABLE: the file is not seekable
  * FOPEN_CACHE_DIR: allow caching this directory
  * FOPEN_STREAM: the file is stream-like (no file position at all)
+ * FOPEN_NOFLUSH: don't flush data cache on close (unless FUSE_WRITEBACK_CACHE)
  */
 #define FOPEN_DIRECT_IO		(1 << 0)
 #define FOPEN_KEEP_CACHE	(1 << 1)
 #define FOPEN_NONSEEKABLE	(1 << 2)
 #define FOPEN_CACHE_DIR		(1 << 3)
 #define FOPEN_STREAM		(1 << 4)
+#define FOPEN_NOFLUSH		(1 << 5)
 
 /**
  * INIT request/reply flags
@@ -518,6 +526,7 @@ enum fuse_opcode {
 	FUSE_COPY_FILE_RANGE	= 47,
 	FUSE_SETUPMAPPING	= 48,
 	FUSE_REMOVEMAPPING	= 49,
+	FUSE_SYNCFS		= 50,
 
 #ifdef linux
 	/* CUSE specific operations */
@@ -939,7 +948,8 @@ struct fuse_notify_retrieve_in {
 };
 
 /* Device ioctls: */
-#define FUSE_DEV_IOC_CLONE	_IOR(229, 0, uint32_t)
+#define FUSE_DEV_IOC_MAGIC	229
+#define FUSE_DEV_IOC_CLONE	_IOR(FUSE_DEV_IOC_MAGIC, 0, uint32_t)
 
 struct fuse_lseek_in {
 	uint64_t	fh;
@@ -992,4 +1002,8 @@ struct fuse_removemapping_one {
 #define FUSE_REMOVEMAPPING_MAX_ENTRY   \
 		(PAGE_SIZE / sizeof(struct fuse_removemapping_one))
 
+struct fuse_syncfs_in {
+	uint64_t	padding;
+};
+
 #endif /* _FUSE_FUSE_KERNEL_H */
diff --git a/sys/fs/fuse/fuse_vnops.c b/sys/fs/fuse/fuse_vnops.c
index 107e6db299e0..c0ec5a94b8d3 100644
--- a/sys/fs/fuse/fuse_vnops.c
+++ b/sys/fs/fuse/fuse_vnops.c
@@ -289,6 +289,10 @@ fuse_flush(struct vnode *vp, struct ucred *cred, pid_t pid, int fflag)
 	if (err)
 		return err;
 
+	if (fufh->fuse_open_flags & FOPEN_NOFLUSH &&
+	    (!fsess_opt_writeback(vnode_mount(vp))))
+		return (0);
+
 	fdisp_init(&fdi, sizeof(*ffi));
 	fdisp_make_vp(&fdi, FUSE_FLUSH, vp, td, cred);
 	ffi = fdi.indata;
diff --git a/tests/sys/fs/fusefs/flush.cc b/tests/sys/fs/fusefs/flush.cc
index 474cdbdb2203..7ba1218b3287 100644
--- a/tests/sys/fs/fusefs/flush.cc
+++ b/tests/sys/fs/fusefs/flush.cc
@@ -109,6 +109,36 @@ TEST_F(Flush, open_twice)
 	EXPECT_EQ(0, close(fd)) << strerror(errno);
 }
 
+/**
+ * Test for FOPEN_NOFLUSH: we expect that zero flush calls will be performed.
+ */
+TEST_F(Flush, open_noflush)
+{
+	const char FULLPATH[] = "mountpoint/some_file.txt";
+	const char RELPATH[] = "some_file.txt";
+	uint64_t ino = 42;
+	uint64_t pid = (uint64_t)getpid();
+	int fd;
+
+	expect_lookup(RELPATH, ino, 1);
+	expect_open(ino, FOPEN_NOFLUSH, 1);
+	EXPECT_CALL(*m_mock, process(
+		ResultOf([=](auto in) {
+			return (in.header.opcode == FUSE_FLUSH &&
+				in.header.nodeid == ino &&
+				in.body.flush.lock_owner == pid &&
+				in.body.flush.fh == FH);
+		}, Eq(true)),
+		_)
+	).Times(0);
+	expect_release();
+
+	fd = open(FULLPATH, O_WRONLY);
+	ASSERT_LE(0, fd) << strerror(errno);
+	// close MUST not flush
+	EXPECT_EQ(0, close(fd)) << strerror(errno);
+}
+
 /*
  * Some FUSE filesystem cache data internally and flush it on release.  Such
  * filesystems may generate errors during release.  On Linux, these get