Downgrade FUSE minor version support and clarify comments

1 files changed, 22 insertions, 31 deletions

diff --git a/pkg/abi/linux/fuse.go b/pkg/abi/linux/fuse.go
index 5616290a5..ed40df564 100644
--- a/pkg/abi/linux/fuse.go
+++ b/pkg/abi/linux/fuse.go
@@ -151,34 +151,27 @@ type FUSEWriteIn struct {
 }
 
 // FUSE_INIT flags, consistent with the ones in include/uapi/linux/fuse.h.
+// Our taget version is 7.23 but we have few implemented in advance.
 const (
-	FUSE_ASYNC_READ          = 1 << 0
-	FUSE_POSIX_LOCKS         = 1 << 1
-	FUSE_FILE_OPS            = 1 << 2
-	FUSE_ATOMIC_O_TRUNC      = 1 << 3
-	FUSE_EXPORT_SUPPORT      = 1 << 4
-	FUSE_BIG_WRITES          = 1 << 5
-	FUSE_DONT_MASK           = 1 << 6
-	FUSE_SPLICE_WRITE        = 1 << 7
-	FUSE_SPLICE_MOVE         = 1 << 8
-	FUSE_SPLICE_READ         = 1 << 9
-	FUSE_FLOCK_LOCKS         = 1 << 10
-	FUSE_HAS_IOCTL_DIR       = 1 << 11
-	FUSE_AUTO_INVAL_DATA     = 1 << 12
-	FUSE_DO_READDIRPLUS      = 1 << 13
-	FUSE_READDIRPLUS_AUTO    = 1 << 14
-	FUSE_ASYNC_DIO           = 1 << 15
-	FUSE_WRITEBACK_CACHE     = 1 << 16
-	FUSE_NO_OPEN_SUPPORT     = 1 << 17
-	FUSE_PARALLEL_DIROPS     = 1 << 18
-	FUSE_HANDLE_KILLPRIV     = 1 << 19
-	FUSE_POSIX_ACL           = 1 << 20
-	FUSE_ABORT_ERROR         = 1 << 21
-	FUSE_MAX_PAGES           = 1 << 22
-	FUSE_CACHE_SYMLINKS      = 1 << 23
-	FUSE_NO_OPENDIR_SUPPORT  = 1 << 24
-	FUSE_EXPLICIT_INVAL_DATA = 1 << 25
-	FUSE_MAP_ALIGNMENT       = 1 << 26
+	FUSE_ASYNC_READ       = 1 << 0
+	FUSE_POSIX_LOCKS      = 1 << 1
+	FUSE_FILE_OPS         = 1 << 2
+	FUSE_ATOMIC_O_TRUNC   = 1 << 3
+	FUSE_EXPORT_SUPPORT   = 1 << 4
+	FUSE_BIG_WRITES       = 1 << 5
+	FUSE_DONT_MASK        = 1 << 6
+	FUSE_SPLICE_WRITE     = 1 << 7
+	FUSE_SPLICE_MOVE      = 1 << 8
+	FUSE_SPLICE_READ      = 1 << 9
+	FUSE_FLOCK_LOCKS      = 1 << 10
+	FUSE_HAS_IOCTL_DIR    = 1 << 11
+	FUSE_AUTO_INVAL_DATA  = 1 << 12
+	FUSE_DO_READDIRPLUS   = 1 << 13
+	FUSE_READDIRPLUS_AUTO = 1 << 14
+	FUSE_ASYNC_DIO        = 1 << 15
+	FUSE_WRITEBACK_CACHE  = 1 << 16
+	FUSE_NO_OPEN_SUPPORT  = 1 << 17
+	FUSE_MAX_PAGES        = 1 << 22 // From FUSE 7.28
 )
 
 // currently supported FUSE protocol version numbers.
@@ -214,7 +207,7 @@ type FUSEInitIn struct {
 }
 
 // FUSEInitOut is the reply sent by the daemon to the kernel
-// for FUSEInitIn.
+// for FUSEInitIn. We target FUSE 7.23; this struct supports 7.28.
 //
 // +marshal
 type FUSEInitOut struct {
@@ -255,9 +248,7 @@ type FUSEInitOut struct {
 	// if the value from daemon is too large.
 	MaxPages uint16
 
-	// MapAlignment is an unknown field and not used by this package at this moment.
-	// Use as a placeholder to be consistent with the FUSE protocol.
-	MapAlignment uint16
+	_ uint16
 
 	_ [8]uint32
 }