* mmap support for common simulators

2001-03-16  Frank Ch. Eigler  <fche@redhat.com>

	Add support for mmap-based memory regions.
	* sim-memopt.c (mmap_next_fd): New global.
	(sim_memory_init): Reinitialize it.
	(OPTION_MEMORY_MAPFILE, memory_option_handler): Support new
	"--memory-mapfile FILE" option.  Check for some errors.
	(do_memopt_add): Conditionally do mmap instead of malloc for
	backing store of simulated memory.  Check for more errors.
	(do_simopt_delete, sim_memory_uninstall): Corresponding cleanup.
	* sim-memopt.h (munmap_length): New member of _sim_memopt.
	* configure.in: Look for mmap/fstat related functions and headers.
	* config.in, configure: Regenerated.

6 files changed, 205 insertions, 12 deletions

diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index 98c5e81..7ca57e7 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,3 +1,17 @@
+2001-03-16  Frank Ch. Eigler  <fche@redhat.com>
+
+	Add support for mmap-based memory regions.
+	* sim-memopt.c (mmap_next_fd): New global.
+	(sim_memory_init): Reinitialize it.
+	(OPTION_MEMORY_MAPFILE, memory_option_handler): Support new
+	"--memory-mapfile FILE" option.  Check for some errors.
+	(do_memopt_add): Conditionally do mmap instead of malloc for
+	backing store of simulated memory.  Check for more errors.
+	(do_simopt_delete, sim_memory_uninstall): Corresponding cleanup.
+	* sim-memopt.h (munmap_length): New member of _sim_memopt.
+	* configure.in: Look for mmap/fstat related functions and headers.
+	* config.in, configure: Regenerated.
+
 2001-03-15  Frank Ch. Eigler  <fche@redhat.com>
 
 	* sim-core.c (sim_core_map_attach): Correct overlap-related
diff --git a/sim/common/config.in b/sim/common/config.in
index 4df9560..0b222e8 100644
--- a/sim/common/config.in
+++ b/sim/common/config.in
@@ -82,6 +82,9 @@
 /* Define if you have the getrusage function.  */
 #undef HAVE_GETRUSAGE
 
+/* Define if you have the mmap function.  */
+#undef HAVE_MMAP
+
 /* Define if you have the munmap function.  */
 #undef HAVE_MUNMAP
 
@@ -145,12 +148,18 @@
 /* Define if you have the <strings.h> header file.  */
 #undef HAVE_STRINGS_H
 
+/* Define if you have the <sys/mman.h> header file.  */
+#undef HAVE_SYS_MMAN_H
+
 /* Define if you have the <sys/param.h> header file.  */
 #undef HAVE_SYS_PARAM_H
 
 /* Define if you have the <sys/resource.h> header file.  */
 #undef HAVE_SYS_RESOURCE_H
 
+/* Define if you have the <sys/stat.h> header file.  */
+#undef HAVE_SYS_STAT_H
+
 /* Define if you have the <sys/time.h> header file.  */
 #undef HAVE_SYS_TIME_H
 
@@ -165,3 +174,9 @@
 
 /* Define if you have the <values.h> header file.  */
 #undef HAVE_VALUES_H
+
+/* Define if you have the nsl library (-lnsl).  */
+#undef HAVE_LIBNSL
+
+/* Define if you have the socket library (-lsocket).  */
+#undef HAVE_LIBSOCKET
diff --git a/sim/common/configure b/sim/common/configure
index 8fc9d04..11c0e64 100755
--- a/sim/common/configure
+++ b/sim/common/configure
@@ -3522,7 +3522,7 @@ fi
 
 
 # These aren't all needed yet, but will be eventually.
-for ac_hdr in stdlib.h string.h strings.h time.h sys/times.h
+for ac_hdr in stdlib.h string.h strings.h time.h sys/times.h sys/stat.h sys/mman.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
@@ -3562,6 +3562,61 @@ else
 fi
 done
 
+for ac_func in mmap munmap
+do
+echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
+echo "configure:3569: checking for $ac_func" >&5
+if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
+  echo $ac_n "(cached) $ac_c" 1>&6
+else
+  cat > conftest.$ac_ext <<EOF
+#line 3574 "configure"
+#include "confdefs.h"
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $ac_func(); below.  */
+#include <assert.h>
+/* Override any gcc2 internal prototype to avoid an error.  */
+/* We use char because int might match the return type of a gcc2
+    builtin and then its argument prototype would still apply.  */
+char $ac_func();
+
+int main() {
+
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined (__stub_$ac_func) || defined (__stub___$ac_func)
+choke me
+#else
+$ac_func();
+#endif
+
+; return 0; }
+EOF
+if { (eval echo configure:3597: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+  rm -rf conftest*
+  eval "ac_cv_func_$ac_func=yes"
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  eval "ac_cv_func_$ac_func=no"
+fi
+rm -f conftest*
+fi
+
+if eval "test \"`echo '$ac_cv_func_'$ac_func`\" = yes"; then
+  echo "$ac_t""yes" 1>&6
+    ac_tr_func=HAVE_`echo $ac_func | tr 'abcdefghijklmnopqrstuvwxyz' 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
+  cat >> confdefs.h <<EOF
+#define $ac_tr_func 1
+EOF
+ 
+else
+  echo "$ac_t""no" 1>&6
+fi
+done
+
 
 trap '' 1 2 15
 cat > confcache <<\EOF
diff --git a/sim/common/configure.in b/sim/common/configure.in
index b8ea538..4421878 100644
--- a/sim/common/configure.in
+++ b/sim/common/configure.in
@@ -34,7 +34,8 @@ fi
 AC_SUBST(TARGET_SUBDIR)
 
 # These aren't all needed yet, but will be eventually.
-AC_CHECK_HEADERS(stdlib.h string.h strings.h time.h sys/times.h)
+AC_CHECK_HEADERS(stdlib.h string.h strings.h time.h sys/times.h sys/stat.h sys/mman.h)
+AC_CHECK_FUNCS(mmap munmap)
 
 AC_OUTPUT(Makefile,
 [case x$CONFIG_HEADERS in xcconfig.h:config.in) echo > stamp-h ;; esac])
diff --git a/sim/common/sim-memopt.c b/sim/common/sim-memopt.c
index 6e12a45..a8e9df6 100644
--- a/sim/common/sim-memopt.c
+++ b/sim/common/sim-memopt.c
@@ -18,6 +18,8 @@ You should have received a copy of the GNU General Public License along
 with this program; if not, write to the Free Software Foundation, Inc.,
 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 
+#include "cconfig.h"
+
 #include "sim-main.h"
 #include "sim-assert.h"
 #include "sim-options.h"
@@ -32,11 +34,26 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
 
-/* Memory fill byte */
+/* Memory fill byte. */
 static unsigned8 fill_byte_value;
 static int fill_byte_flag = 0;
 
+/* Memory mapping; see OPTION_MEMORY_MAPFILE. */
+static int mmap_next_fd = -1;
+
 /* Memory command line options. */
 
 enum {
@@ -46,7 +63,8 @@ enum {
   OPTION_MEMORY_INFO,
   OPTION_MEMORY_ALIAS,
   OPTION_MEMORY_CLEAR,
-  OPTION_MEMORY_FILL
+  OPTION_MEMORY_FILL,
+  OPTION_MEMORY_MAPFILE
 };
 
 static DECLARE_OPTION_HANDLER (memory_option_handler);
@@ -80,6 +98,12 @@ static const OPTION memory_options[] =
       '\0', NULL, "Clear subsequently added memory regions",
       memory_option_handler },
 
+#if defined(HAVE_MMAP) && defined(HAVE_MUNMAP)
+  { {"memory-mapfile", required_argument, NULL, OPTION_MEMORY_MAPFILE },
+      '\0', "FILE", "Memory-map next memory region from file",
+      memory_option_handler },
+#endif
+
   { {"memory-info", no_argument, NULL, OPTION_MEMORY_INFO },
       '\0', NULL, "List configurable memory regions",
       memory_option_handler },
@@ -104,6 +128,7 @@ do_memopt_add (SIM_DESC sd,
   void *fill_buffer;
   unsigned fill_length;
   void *free_buffer;
+  unsigned long free_length;
 
   if (buffer != NULL)
     {
@@ -113,6 +138,7 @@ do_memopt_add (SIM_DESC sd,
 		       addr, nr_bytes, modulo, NULL, buffer);
 
       free_buffer = buffer;
+      free_length = 0;
       fill_buffer = buffer;
       fill_length = (modulo == 0) ? nr_bytes : modulo;
     }
@@ -123,12 +149,45 @@ do_memopt_add (SIM_DESC sd,
       int padding = (addr % sizeof (unsigned64));
       unsigned long bytes = (modulo == 0 ? nr_bytes : modulo) + padding;
 
-      /* If filling with non-zero value, do not use clearing allocator. */
+      free_buffer = NULL;
+      free_length = bytes;
 
-      if (fill_byte_flag && fill_byte_value != 0)
-        free_buffer = xmalloc (bytes); /* don't clear */
-      else
-        free_buffer = zalloc (bytes); /* clear */
+#ifdef HAVE_MMAP
+      /* Memory map or malloc(). */
+      if (mmap_next_fd >= 0)
+	{
+	  /* Check that given file is big enough. */
+	  struct stat s;
+	  int rc;
+
+	  /* Some kernels will SIGBUS the application if mmap'd file
+	     is not large enough.  */ 
+	  rc = fstat (mmap_next_fd, &s);
+	  if (rc < 0 || s.st_size < bytes)
+	    {
+	      sim_io_error (sd,
+			    "Error, cannot confirm that mmap file is large enough "
+			    "(>= %d bytes)\n", bytes);
+	    }
+
+	  free_buffer = mmap (0, bytes, PROT_READ|PROT_WRITE, MAP_SHARED, mmap_next_fd, 0);
+	  if (free_buffer == 0 || free_buffer == (char*)-1) /* MAP_FAILED */
+	    {
+	      sim_io_error (sd, "Error, cannot mmap file (%s).\n",
+			    strerror(errno));
+	    }
+	}
+#endif 
+
+      /* Need heap allocation? */ 
+      if (free_buffer == NULL)
+	{
+	  /* If filling with non-zero value, do not use clearing allocator. */
+	  if (fill_byte_flag && fill_byte_value != 0)
+	    free_buffer = xmalloc (bytes); /* don't clear */
+	  else
+	    free_buffer = zalloc (bytes); /* clear */
+	}
 
       aligned_buffer = (char*) free_buffer + padding;
 
@@ -162,6 +221,16 @@ do_memopt_add (SIM_DESC sd,
   (*entry)->modulo = modulo;
   (*entry)->buffer = free_buffer;
 
+  /* Record memory unmapping info.  */
+  if (mmap_next_fd >= 0)
+    {
+      (*entry)->munmap_length = free_length;
+      close (mmap_next_fd);
+      mmap_next_fd = -1;
+    }
+  else
+    (*entry)->munmap_length = 0;
+
   return (*entry);
 }
 
@@ -186,7 +255,15 @@ do_memopt_delete (SIM_DESC sd,
     }
   /* delete any buffer */
   if ((*entry)->buffer != NULL)
-    zfree ((*entry)->buffer);
+    {
+#ifdef HAVE_MUNMAP
+      if ((*entry)->munmap_length > 0)
+	munmap ((*entry)->buffer, (*entry)->munmap_length);
+      else
+#endif
+	zfree ((*entry)->buffer);
+    }
+
   /* delete it and its aliases */
   alias = *entry;
   *entry = (*entry)->next;
@@ -367,6 +444,25 @@ memory_option_handler (SIM_DESC sd, sim_cpu *cpu, int opt,
 	break;
       }
 
+    case OPTION_MEMORY_MAPFILE:
+      {
+	if (mmap_next_fd >= 0)
+	  {
+	    sim_io_eprintf (sd, "Duplicate memory-mapfile option\n");
+	    return SIM_RC_FAIL;
+	  }
+
+	mmap_next_fd = open (arg, O_RDWR);
+	if (mmap_next_fd < 0)
+	  {
+	    sim_io_eprintf (sd, "Cannot open file `%s': %s\n",
+			    arg, strerror(errno));
+	    return SIM_RC_FAIL;
+	  }
+
+	return SIM_RC_OK;
+      }
+
     case OPTION_MEMORY_INFO:
       {
 	sim_memopt *entry;
@@ -445,7 +541,14 @@ sim_memory_uninstall (SIM_DESC sd)
     {
       /* delete any buffer */
       if ((*entry)->buffer != NULL)
-	zfree ((*entry)->buffer);
+	{
+#ifdef HAVE_MUNMAP
+	  if ((*entry)->munmap_length > 0)
+	    munmap ((*entry)->buffer, (*entry)->munmap_length);
+	  else
+#endif
+	    zfree ((*entry)->buffer);
+	}
 
       /* delete it and its aliases */
       alias = *entry;
@@ -467,6 +570,10 @@ sim_memory_uninstall (SIM_DESC sd)
 static SIM_RC
 sim_memory_init (SIM_DESC sd)
 {
-  /* FIXME: anything needed? */
+  /* Reinitialize option modifier flags, in case they were left
+     over from a previous sim startup event.  */
+  fill_byte_flag = 0;
+  mmap_next_fd = -1;
+
   return SIM_RC_OK;
 }
diff --git a/sim/common/sim-memopt.h b/sim/common/sim-memopt.h
index 287c576..cbaad0c 100644
--- a/sim/common/sim-memopt.h
+++ b/sim/common/sim-memopt.h
@@ -31,6 +31,7 @@ struct _sim_memopt {
   unsigned_word nr_bytes;
   unsigned modulo;
   void *buffer;
+  unsigned long munmap_length;
   sim_memopt *alias; /* linked list */
   sim_memopt *next;
 };