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authorDavid S. Miller <davem@davemloft.net>2009-04-13 14:41:05 -0700
committerDavid S. Miller <davem@davemloft.net>2009-04-13 14:41:05 -0700
commit83400207a07584539366f6859362db6872809a12 (patch)
treefad187f8b3bebf1b387ec42ef8143e6f4e49a256 /arch/frv/include/asm/user.h
parent0d489ffb76de0fe804cf06a9d4d11fa7342d74b9 (diff)
parent80a04d3f2f94fb68b5df05e3ac6697130bc3467a (diff)
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts: MAINTAINERS
Diffstat (limited to 'arch/frv/include/asm/user.h')
-rw-r--r--arch/frv/include/asm/user.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/frv/include/asm/user.h b/arch/frv/include/asm/user.h
new file mode 100644
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+++ b/arch/frv/include/asm/user.h
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+/* user.h: FR-V core file format stuff
+ *
+ * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _ASM_USER_H
+#define _ASM_USER_H
+
+#include <asm/page.h>
+#include <asm/registers.h>
+
+/* Core file format: The core file is written in such a way that gdb
+ * can understand it and provide useful information to the user (under
+ * linux we use the 'trad-core' bfd). There are quite a number of
+ * obstacles to being able to view the contents of the floating point
+ * registers, and until these are solved you will not be able to view
+ * the contents of them. Actually, you can read in the core file and
+ * look at the contents of the user struct to find out what the
+ * floating point registers contain.
+ *
+ * The actual file contents are as follows:
+ * UPAGE:
+ * 1 page consisting of a user struct that tells gdb what is present
+ * in the file. Directly after this is a copy of the task_struct,
+ * which is currently not used by gdb, but it may come in useful at
+ * some point. All of the registers are stored as part of the
+ * upage. The upage should always be only one page.
+ *
+ * DATA:
+ * The data area is stored. We use current->end_text to
+ * current->brk to pick up all of the user variables, plus any
+ * memory that may have been malloced. No attempt is made to
+ * determine if a page is demand-zero or if a page is totally
+ * unused, we just cover the entire range. All of the addresses are
+ * rounded in such a way that an integral number of pages is
+ * written.
+ *
+ * STACK:
+ * We need the stack information in order to get a meaningful
+ * backtrace. We need to write the data from (esp) to
+ * current->start_stack, so we round each of these off in order to
+ * be able to write an integer number of pages. The minimum core
+ * file size is 3 pages, or 12288 bytes.
+ */
+
+/* When the kernel dumps core, it starts by dumping the user struct -
+ * this will be used by gdb to figure out where the data and stack segments
+ * are within the file, and what virtual addresses to use.
+ */
+struct user {
+ /* We start with the registers, to mimic the way that "memory" is returned
+ * from the ptrace(3,...) function. */
+ struct user_context regs;
+
+ /* The rest of this junk is to help gdb figure out what goes where */
+ unsigned long u_tsize; /* Text segment size (pages). */
+ unsigned long u_dsize; /* Data segment size (pages). */
+ unsigned long u_ssize; /* Stack segment size (pages). */
+ unsigned long start_code; /* Starting virtual address of text. */
+ unsigned long start_stack; /* Starting virtual address of stack area.
+ * This is actually the bottom of the stack,
+ * the top of the stack is always found in the
+ * esp register. */
+ long int signal; /* Signal that caused the core dump. */
+
+ unsigned long magic; /* To uniquely identify a core file */
+ char u_comm[32]; /* User command that was responsible */
+};
+
+#define NBPG PAGE_SIZE
+#define UPAGES 1
+#define HOST_TEXT_START_ADDR (u.start_code)
+#define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)
+
+#endif