fuse integration: add POSIX compliance test suite

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test/fuse_integration/fallocate_linux.go

@@ -0,0 +1,38 @@
+//go:build linux
+
+package fuse
+
+import (
+	"syscall"
+)
+
+// File allocation support for Linux
+
+const (
+	// Fallocate flags
+	FALLOC_FL_KEEP_SIZE      = 0x01
+	FALLOC_FL_PUNCH_HOLE     = 0x02
+	FALLOC_FL_NO_HIDE_STALE  = 0x04
+	FALLOC_FL_COLLAPSE_RANGE = 0x08
+	FALLOC_FL_ZERO_RANGE     = 0x10
+	FALLOC_FL_INSERT_RANGE   = 0x20
+	FALLOC_FL_UNSHARE_RANGE  = 0x40
+)
+
+func fallocateFile(fd int, mode int, offset int64, length int64) error {
+	_, _, errno := syscall.Syscall6(syscall.SYS_FALLOCATE,
+		uintptr(fd),
+		uintptr(mode),
+		uintptr(offset),
+		uintptr(length),
+		0, 0)
+
+	if errno != 0 {
+		return errno
+	}
+	return nil
+}
+
+func isFallocateSupported() bool {
+	return true
+}