fs: retry preallocate on Linux if interrupted by signal

internal/fs/preallocate_linux.go

@@ -2,6 +2,7 @@ package fs
 
 import (
 	"os"
+	"syscall"
 
 	"golang.org/x/sys/unix"
 )
@@ -12,5 +13,17 @@ func PreallocateFile(wr *os.File, size int64) error {
 	}
 	// int fallocate(int fd, int mode, off_t offset, off_t len)
 	// use mode = 0 to also change the file size
-	return unix.Fallocate(int(wr.Fd()), 0, 0, size)
+	return ignoringEINTR(func() error { return unix.Fallocate(int(wr.Fd()), 0, 0, size) })
+}
+
+// ignoringEINTR makes a function call and repeats it if it returns
+// an EINTR error.
+// copied from /usr/lib/go/src/internal/poll/fd_posix.go of go 1.23.1
+func ignoringEINTR(fn func() error) error {
+	for {
+		err := fn()
+		if err != syscall.EINTR {
+			return err
+		}
+	}
 }