gold/

	* configure.ac: Add check for fallocate.
	* configure: Regenerate.
	* config.in: Regenerate.

	* options.h (class General_options): Add --mmap-output-file and
	--posix-fallocate options.
	* output.cc: (posix_fallocate): Remove; replace with...
	(gold_fallocate): New function.
	(Output_file::map_no_anonymous): Call gold_fallocate.
	(Output_file::map): Check --mmap-output-file option.

1 files changed, 24 insertions, 16 deletions

diff --git a/gold/output.cc b/gold/output.cc
index 2236916054..99890ebae1 100644
--- a/gold/output.cc
+++ b/gold/output.cc
@@ -111,20 +111,6 @@ extern "C" void *gold_mremap(void *, size_t, size_t, int);
 # define MREMAP_MAYMOVE 1
 #endif
 
-#ifndef HAVE_POSIX_FALLOCATE
-// A dummy, non general, version of posix_fallocate.  Here we just set
-// the file size and hope that there is enough disk space.  FIXME: We
-// could allocate disk space by walking block by block and writing a
-// zero byte into each block.
-static int
-posix_fallocate(int o, off_t offset, off_t len)
-{
-  if (ftruncate(o, offset + len) < 0)
-    return errno;
-  return 0;
-}
-#endif // !defined(HAVE_POSIX_FALLOCATE)
-
 // Mingw does not have S_ISLNK.
 #ifndef S_ISLNK
 # define S_ISLNK(mode) 0
@@ -133,6 +119,27 @@ posix_fallocate(int o, off_t offset, off_t len)
 namespace gold
 {
 
+// A wrapper around posix_fallocate.  If we don't have posix_fallocate,
+// or the --no-posix-fallocate option is set, we try the fallocate
+// system call directly.  If that fails, we use ftruncate to set
+// the file size and hope that there is enough disk space.
+
+static int
+gold_fallocate(int o, off_t offset, off_t len)
+{
+#ifdef HAVE_POSIX_FALLOCATE
+  if (parameters->options().posix_fallocate())
+    return ::posix_fallocate(o, offset, len);
+#endif // defined(HAVE_POSIX_FALLOCATE)
+#ifdef HAVE_FALLOCATE
+  if (::fallocate(o, 0, offset, len) == 0)
+    return 0;
+#endif // defined(HAVE_FALLOCATE)
+  if (::ftruncate(o, offset + len) < 0)
+    return errno;
+  return 0;
+}
+
 // Output_data variables.
 
 bool Output_data::allocated_sizes_are_fixed;
@@ -5014,7 +5021,7 @@ Output_file::map_no_anonymous(bool writable)
   // but that would be a more significant performance hit.
   if (writable)
     {
-      int err = ::posix_fallocate(o, 0, this->file_size_);
+      int err = gold_fallocate(o, 0, this->file_size_);
       if (err != 0)
        gold_fatal(_("%s: %s"), this->name_, strerror(err));
     }
@@ -5041,7 +5048,8 @@ Output_file::map_no_anonymous(bool writable)
 void
 Output_file::map()
 {
-  if (this->map_no_anonymous(true))
+  if (parameters->options().mmap_output_file()
+      && this->map_no_anonymous(true))
     return;
 
   // The mmap call might fail because of file system issues: the file