hurd/

2007-11-19  Neal H. Walfield  <neal@gnu.org>

	* Makefile.am (includehurd_HEADERS): Add exceptions.h.
	* headers.m4: Link $(BUILDIR)/include/hurd/exceptions.h to
	exceptions.h.
	* exceptions.h: New file.

viengoos/

2007-11-19  Neal H. Walfield  <neal@gnu.org>

	* thread.h (struct thread): Add fields have_exception and
	exception.
	(UTCB_AREA_SIZE): Provide space for two UTCBs.
	* thread.c: Include <hurd/exceptions.h>.
	(thread_create_in): For each thread that we allocate, allocate two
	consecutive l4 thread ids.
	(thread_commission): Initialize the main thread and the exception
	thread.
	(thread_decommission): Destroy both the main thread and the
	exception thread.

	* rm.h: Add RM_exception_collect.
	(rm_method_id_string): Handle RM_exception_collect.
	(exception_collect): New RPC method.
	* server.c: Include <hurd/exceptions.h>.
	(server_loop): If FROM is the exception thread, look up the thread
	object using the main thread id.  Propagate any fault to the
	exception thread.  If not immediately successful, save the message
	in THREAD->EXCEPTION and set THREAD->HAVE_EXCEPTION.  Implement
	the exception_collect method.

	(DEBUG): Also print the method number.

libhurd-mm/

2007-11-19  Neal H. Walfield  <neal@gnu.org>

	* Makefile.am (libhurd_mm_a_SOURCES): Add exceptions.h,
	exceptions.c, pager.h, pager.c, anonymous.h and anonymous.c.
	* headers.m4: Link $(BUILDDIR)/include/hurd/pager.h to pager.h.
	Link $(BUILDDIR)/include/hurd/anonymous.h to anonymous.h.
	* mm-init.c: Include "exceptions.h".
	(mm_init): Call exception_handler_init.
	* pager.h: Completely rewrite.
	* pager.c: Likewise.
	* anonymous.h: Likewise.
	* anonymous.c: Likewise.
	* exceptions.h: New file.
	* exceptions.c: Likewise.
	* mmap.c: Include <hurd/anonymous.h>.
	(mmap): Rewrite to use an anonymous pager.

1 files changed, 135 insertions, 0 deletions

diff --git a/libhurd-mm/exceptions.c b/libhurd-mm/exceptions.c
new file mode 100644
index 0000000..32e9361
--- /dev/null
+++ b/libhurd-mm/exceptions.c
@@ -0,0 +1,135 @@
+/* exceptions.c - Exception handler implementation.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   Written by Neal H. Walfield <neal@gnu.org>.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <hurd/startup.h>
+#include <hurd/stddef.h>
+#include <hurd/exceptions.h>
+#include <l4/thread.h>
+
+#include "pager.h"
+
+extern struct hurd_startup_data *__hurd_startup_data;
+
+/* Return the next word.  */
+#define ARG() \
+  ({ \
+    assert (args_read < expected_words); \
+    l4_msg_word (msg, args_read ++); \
+  })
+
+  /* Return word WORD_.  */
+#if L4_WORDSIZE == 32
+#define ARG64() \
+  ({ \
+    union { l4_uint64_t raw; struct { l4_uint32_t word[2]; }; } value_; \
+    value_.word[0] = ARG (); \
+    value_.word[1] = ARG (); \
+    value_.raw; \
+  })
+#define ARG64_WORDS 2
+#else
+#define ARG64(word_) ARG(word_)
+#define ARG64_WORDS 1
+#endif
+
+#define ARG_ADDR() ((addr_t) { ARG64() })
+
+/* Check that the received message contains WORDS untyped words.  */
+#define CHECK(words, words64) \
+  ({ \
+    expected_words = (words) + (words64) * ARG64_WORDS; \
+    if (l4_untyped_words (msg_tag) != expected_words \
+        || l4_typed_words (msg_tag) != 0) \
+      { \
+        debug (1, "Invalid format for %s: expected %d words, got %d", \
+	       exception_method_id_string (label), \
+               expected_words, l4_untyped_words (msg_tag)); \
+        continue; \
+      } \
+  })
+
+static void
+exception_thread (void)
+{
+  debug (5, "Exception thread launched (0x%x.%x)",
+	 l4_thread_no (l4_myself ()), l4_version (l4_myself ()));
+
+  for (;;)
+    {
+      l4_msg_t msg;
+      rm_exception_collect_marshal (&msg);
+      l4_msg_load (msg);
+
+      l4_thread_id_t from;
+      l4_msg_tag_t msg_tag = l4_reply_wait (__hurd_startup_data->rm, &from);
+      if (l4_ipc_failed (msg_tag))
+	panic ("Receiving message failed: %u", (l4_error_code () >> 1) & 0x7);
+
+      l4_msg_store (msg_tag, msg);
+      l4_word_t label;
+      label = l4_label (msg_tag);
+
+      int args_read = 0;
+      int expected_words;
+      switch (label)
+	{
+	case EXCEPTION_fault:
+	  CHECK (2, 1);
+
+	  addr_t fault = ARG_ADDR ();
+	  uintptr_t ip = ARG ();
+	  struct exception_info info;
+	  info.raw = ARG ();
+
+	  bool r = pager_fault (fault, ip, info);
+	  if (r)
+	    /* The appears to have been resolved.  Resume the
+	       thread.  */
+	    l4_start (hurd_main_thread (l4_myself ()));
+	  else
+	    {
+	      debug (1, "Failed to handle fault at " ADDR_FMT,
+		     ADDR_PRINTF (fault));
+	      /* XXX: Should raise SIGSEGV.  */
+	    }
+
+	  /* Resume the main thread.  */
+	  
+	  break;
+
+	default:
+	  debug (1, "Unknown message id: %d", label);
+	}
+    }
+}
+
+static char stack[2 * PAGESIZE] __attribute__ ((aligned(PAGESIZE)));
+
+void
+exception_handler_init (void)
+{
+  /* XXX: This only works for architectures on which the stack grows
+     downward.  */
+  void *sp = stack + sizeof (stack);
+
+  l4_thread_id_t tid = hurd_exception_thread (l4_myself ());
+  l4_start_sp_ip (tid, (l4_word_t) sp, (l4_word_t) &exception_thread);
+}