[PATCH] uml: S390 preparation, abstract host page fault data
This patch removes the arch-specific fault/trap-infos from thread and
skas-regs.
It adds a new struct faultinfo, that is arch-specific defined in
sysdep/faultinfo.h.
The structure is inserted in thread.arch and thread.regs.skas and
thread.regs.tt
Now, segv and other trap-handlers can copy the contents from regs.X.faultinfo
to thread.arch.faultinfo with one simple assignment.
Also, the number of macros necessary is reduced to
FAULT_ADDRESS(struct faultinfo)
extracts the faulting address from faultinfo
FAULT_WRITE(struct faultinfo)
extracts the "is_write" flag
SEGV_IS_FIXABLE(struct faultinfo)
is true for the fixable segvs, i.e. (TRAP == 14)
on i386
UPT_FAULTINFO(regs)
result is (struct faultinfo *) to the faultinfo
in regs->skas.faultinfo
GET_FAULTINFO_FROM_SC(struct faultinfo, struct sigcontext *)
copies the relevant parts of the sigcontext to
struct faultinfo.
On SIGSEGV, call user_signal() instead of handle_segv(), if the architecture
provides the information needed in PTRACE_FAULTINFO, or if PTRACE_FAULTINFO is
missing, because segv-stub will provide the info.
The benefit of the change is, that in case of a non-fixable SIGSEGV, we can
give user processes a SIGSEGV, instead of possibly looping on pagefault
handling.
Since handle_segv() sikked arch_fixup() implicitly by passing ip==0 to segv(),
I changed segv() to call arch_fixup() only, if !is_user.
Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/include/kern_util.h b/arch/um/include/kern_util.h
index 15389c8..e5fec55 100644
--- a/arch/um/include/kern_util.h
+++ b/arch/um/include/kern_util.h
@@ -8,6 +8,7 @@
#include "linux/threads.h"
#include "sysdep/ptrace.h"
+#include "sysdep/faultinfo.h"
extern int ncpus;
extern char *linux_prog;
@@ -31,8 +32,8 @@
extern unsigned long alloc_stack(int order, int atomic);
extern int do_signal(void);
extern int is_stack_fault(unsigned long sp);
-extern unsigned long segv(unsigned long address, unsigned long ip,
- int is_write, int is_user, void *sc);
+extern unsigned long segv(struct faultinfo fi, unsigned long ip,
+ int is_user, void *sc);
extern int handle_page_fault(unsigned long address, unsigned long ip,
int is_write, int is_user, int *code_out);
extern void syscall_ready(void);
@@ -82,7 +83,7 @@
extern void unprotect_stack(unsigned long stack);
extern void do_uml_exitcalls(void);
extern int attach_debugger(int idle_pid, int pid, int stop);
-extern void bad_segv(unsigned long address, unsigned long ip, int is_write);
+extern void bad_segv(struct faultinfo fi, unsigned long ip);
extern int config_gdb(char *str);
extern int remove_gdb(void);
extern char *uml_strdup(char *string);
diff --git a/arch/um/include/sysdep-i386/faultinfo.h b/arch/um/include/sysdep-i386/faultinfo.h
new file mode 100644
index 0000000..db437cc
--- /dev/null
+++ b/arch/um/include/sysdep-i386/faultinfo.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2004 Fujitsu Siemens Computers GmbH
+ * Author: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
+ * Licensed under the GPL
+ */
+
+#ifndef __FAULTINFO_I386_H
+#define __FAULTINFO_I386_H
+
+/* this structure contains the full arch-specific faultinfo
+ * from the traps.
+ * On i386, ptrace_faultinfo unfortunately doesn't provide
+ * all the info, since trap_no is missing.
+ * All common elements are defined at the same position in
+ * both structures, thus making it easy to copy the
+ * contents without knowledge about the structure elements.
+ */
+struct faultinfo {
+ int error_code; /* in ptrace_faultinfo misleadingly called is_write */
+ unsigned long cr2; /* in ptrace_faultinfo called addr */
+ int trap_no; /* missing in ptrace_faultinfo */
+};
+
+#define FAULT_WRITE(fi) ((fi).error_code & 2)
+#define FAULT_ADDRESS(fi) ((fi).cr2)
+
+#define PTRACE_FULL_FAULTINFO 0
+
+#endif
diff --git a/arch/um/include/sysdep-i386/ptrace.h b/arch/um/include/sysdep-i386/ptrace.h
index 661d495..84ec7ff 100644
--- a/arch/um/include/sysdep-i386/ptrace.h
+++ b/arch/um/include/sysdep-i386/ptrace.h
@@ -31,6 +31,7 @@
#ifdef UML_CONFIG_MODE_SKAS
#include "skas_ptregs.h"
+#include "sysdep/faultinfo.h"
#define REGS_IP(r) ((r)[HOST_IP])
#define REGS_SP(r) ((r)[HOST_SP])
@@ -53,12 +54,6 @@
#define REGS_RESTART_SYSCALL(r) IP_RESTART_SYSCALL(REGS_IP(r))
-#define REGS_SEGV_IS_FIXABLE(r) SEGV_IS_FIXABLE((r)->trap_type)
-
-#define REGS_FAULT_ADDR(r) ((r)->fault_addr)
-
-#define REGS_FAULT_WRITE(r) FAULT_WRITE((r)->fault_type)
-
#endif
#ifndef PTRACE_SYSEMU_SINGLESTEP
#define PTRACE_SYSEMU_SINGLESTEP 32
@@ -71,6 +66,7 @@
struct tt_regs {
long syscall;
void *sc;
+ struct faultinfo faultinfo;
} tt;
#endif
#ifdef UML_CONFIG_MODE_SKAS
@@ -78,9 +74,7 @@
unsigned long regs[HOST_FRAME_SIZE];
unsigned long fp[HOST_FP_SIZE];
unsigned long xfp[HOST_XFP_SIZE];
- unsigned long fault_addr;
- unsigned long fault_type;
- unsigned long trap_type;
+ struct faultinfo faultinfo;
long syscall;
int is_user;
} skas;
@@ -217,15 +211,8 @@
#define UPT_SYSCALL_NR(r) UPT_ORIG_EAX(r)
#define UPT_SYSCALL_RET(r) UPT_EAX(r)
-#define UPT_SEGV_IS_FIXABLE(r) \
- CHOOSE_MODE(SC_SEGV_IS_FIXABLE(UPT_SC(r)), \
- REGS_SEGV_IS_FIXABLE(&r->skas))
-
-#define UPT_FAULT_ADDR(r) \
- __CHOOSE_MODE(SC_FAULT_ADDR(UPT_SC(r)), REGS_FAULT_ADDR(&r->skas))
-
-#define UPT_FAULT_WRITE(r) \
- CHOOSE_MODE(SC_FAULT_WRITE(UPT_SC(r)), REGS_FAULT_WRITE(&r->skas))
+#define UPT_FAULTINFO(r) \
+ CHOOSE_MODE((&(r)->tt.faultinfo), (&(r)->skas.faultinfo))
#endif
diff --git a/arch/um/include/sysdep-i386/sigcontext.h b/arch/um/include/sysdep-i386/sigcontext.h
index dfee589..1fe7292 100644
--- a/arch/um/include/sysdep-i386/sigcontext.h
+++ b/arch/um/include/sysdep-i386/sigcontext.h
@@ -13,15 +13,12 @@
#define SC_RESTART_SYSCALL(sc) IP_RESTART_SYSCALL(SC_IP(sc))
#define SC_SET_SYSCALL_RETURN(sc, result) SC_EAX(sc) = (result)
-#define SC_FAULT_ADDR(sc) SC_CR2(sc)
-#define SC_FAULT_TYPE(sc) SC_ERR(sc)
-
-#define FAULT_WRITE(err) (err & 2)
-#define TO_SC_ERR(is_write) ((is_write) ? 2 : 0)
-
-#define SC_FAULT_WRITE(sc) (FAULT_WRITE(SC_ERR(sc)))
-
-#define SC_TRAP_TYPE(sc) SC_TRAPNO(sc)
+#define GET_FAULTINFO_FROM_SC(fi,sc) \
+ { \
+ (fi).cr2 = SC_CR2(sc); \
+ (fi).error_code = SC_ERR(sc); \
+ (fi).trap_no = SC_TRAPNO(sc); \
+ }
/* ptrace expects that, at the start of a system call, %eax contains
* -ENOSYS, so this makes it so.
@@ -29,9 +26,7 @@
#define SC_START_SYSCALL(sc) do SC_EAX(sc) = -ENOSYS; while(0)
/* This is Page Fault */
-#define SEGV_IS_FIXABLE(trap) (trap == 14)
-
-#define SC_SEGV_IS_FIXABLE(sc) (SEGV_IS_FIXABLE(SC_TRAPNO(sc)))
+#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
extern unsigned long *sc_sigmask(void *sc_ptr);
extern int sc_get_fpregs(unsigned long buf, void *sc_ptr);
diff --git a/arch/um/include/sysdep-i386/skas_ptrace.h b/arch/um/include/sysdep-i386/skas_ptrace.h
new file mode 100644
index 0000000..e27b8a7
--- /dev/null
+++ b/arch/um/include/sysdep-i386/skas_ptrace.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __SYSDEP_I386_SKAS_PTRACE_H
+#define __SYSDEP_I386_SKAS_PTRACE_H
+
+struct ptrace_faultinfo {
+ int is_write;
+ unsigned long addr;
+};
+
+struct ptrace_ldt {
+ int func;
+ void *ptr;
+ unsigned long bytecount;
+};
+
+#define PTRACE_LDT 54
+
+#endif
diff --git a/arch/um/include/sysdep-ia64/skas_ptrace.h b/arch/um/include/sysdep-ia64/skas_ptrace.h
new file mode 100644
index 0000000..25a38e7
--- /dev/null
+++ b/arch/um/include/sysdep-ia64/skas_ptrace.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __SYSDEP_IA64_SKAS_PTRACE_H
+#define __SYSDEP_IA64_SKAS_PTRACE_H
+
+struct ptrace_faultinfo {
+ int is_write;
+ unsigned long addr;
+};
+
+struct ptrace_ldt {
+ int func;
+ void *ptr;
+ unsigned long bytecount;
+};
+
+#define PTRACE_LDT 54
+
+#endif
diff --git a/arch/um/include/sysdep-ppc/skas_ptrace.h b/arch/um/include/sysdep-ppc/skas_ptrace.h
new file mode 100644
index 0000000..d9fbbac
--- /dev/null
+++ b/arch/um/include/sysdep-ppc/skas_ptrace.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __SYSDEP_PPC_SKAS_PTRACE_H
+#define __SYSDEP_PPC_SKAS_PTRACE_H
+
+struct ptrace_faultinfo {
+ int is_write;
+ unsigned long addr;
+};
+
+struct ptrace_ldt {
+ int func;
+ void *ptr;
+ unsigned long bytecount;
+};
+
+#define PTRACE_LDT 54
+
+#endif
diff --git a/arch/um/include/sysdep-x86_64/faultinfo.h b/arch/um/include/sysdep-x86_64/faultinfo.h
new file mode 100644
index 0000000..cb917b0
--- /dev/null
+++ b/arch/um/include/sysdep-x86_64/faultinfo.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2004 Fujitsu Siemens Computers GmbH
+ * Author: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
+ * Licensed under the GPL
+ */
+
+#ifndef __FAULTINFO_X86_64_H
+#define __FAULTINFO_X86_64_H
+
+/* this structure contains the full arch-specific faultinfo
+ * from the traps.
+ * On i386, ptrace_faultinfo unfortunately doesn't provide
+ * all the info, since trap_no is missing.
+ * All common elements are defined at the same position in
+ * both structures, thus making it easy to copy the
+ * contents without knowledge about the structure elements.
+ */
+struct faultinfo {
+ int error_code; /* in ptrace_faultinfo misleadingly called is_write */
+ unsigned long cr2; /* in ptrace_faultinfo called addr */
+ int trap_no; /* missing in ptrace_faultinfo */
+};
+
+#define FAULT_WRITE(fi) ((fi).error_code & 2)
+#define FAULT_ADDRESS(fi) ((fi).cr2)
+
+#define PTRACE_FULL_FAULTINFO 1
+
+#endif
diff --git a/arch/um/include/sysdep-x86_64/ptrace.h b/arch/um/include/sysdep-x86_64/ptrace.h
index 915c82d..348e8fc 100644
--- a/arch/um/include/sysdep-x86_64/ptrace.h
+++ b/arch/um/include/sysdep-x86_64/ptrace.h
@@ -9,6 +9,7 @@
#include "uml-config.h"
#include "user_constants.h"
+#include "sysdep/faultinfo.h"
#define MAX_REG_OFFSET (UM_FRAME_SIZE)
#define MAX_REG_NR ((MAX_REG_OFFSET) / sizeof(unsigned long))
@@ -83,6 +84,7 @@
long syscall;
unsigned long orig_rax;
void *sc;
+ struct faultinfo faultinfo;
} tt;
#endif
#ifdef UML_CONFIG_MODE_SKAS
@@ -90,9 +92,7 @@
/* XXX */
unsigned long regs[27];
unsigned long fp[65];
- unsigned long fault_addr;
- unsigned long fault_type;
- unsigned long trap_type;
+ struct faultinfo faultinfo;
long syscall;
int is_user;
} skas;
@@ -241,14 +241,8 @@
CHOOSE_MODE(SC_SEGV_IS_FIXABLE(UPT_SC(r)), \
REGS_SEGV_IS_FIXABLE(&r->skas))
-#define UPT_FAULT_ADDR(r) \
- __CHOOSE_MODE(SC_FAULT_ADDR(UPT_SC(r)), REGS_FAULT_ADDR(&r->skas))
-
-#define UPT_FAULT_WRITE(r) \
- CHOOSE_MODE(SC_FAULT_WRITE(UPT_SC(r)), REGS_FAULT_WRITE(&r->skas))
-
-#define UPT_TRAP(r) __CHOOSE_MODE(SC_TRAP_TYPE(UPT_SC(r)), REGS_TRAP(&r->skas))
-#define UPT_ERR(r) __CHOOSE_MODE(SC_FAULT_TYPE(UPT_SC(r)), REGS_ERR(&r->skas))
+#define UPT_FAULTINFO(r) \
+ CHOOSE_MODE((&(r)->tt.faultinfo), (&(r)->skas.faultinfo))
#endif
diff --git a/arch/um/include/sysdep-x86_64/sigcontext.h b/arch/um/include/sysdep-x86_64/sigcontext.h
index 1e38a54..2a78260 100644
--- a/arch/um/include/sysdep-x86_64/sigcontext.h
+++ b/arch/um/include/sysdep-x86_64/sigcontext.h
@@ -17,11 +17,12 @@
#define SC_FAULT_ADDR(sc) SC_CR2(sc)
#define SC_FAULT_TYPE(sc) SC_ERR(sc)
-#define FAULT_WRITE(err) ((err) & 2)
-
-#define SC_FAULT_WRITE(sc) FAULT_WRITE(SC_FAULT_TYPE(sc))
-
-#define SC_TRAP_TYPE(sc) SC_TRAPNO(sc)
+#define GET_FAULTINFO_FROM_SC(fi,sc) \
+ { \
+ (fi).cr2 = SC_CR2(sc); \
+ (fi).error_code = SC_ERR(sc); \
+ (fi).trap_no = SC_TRAPNO(sc); \
+ }
/* ptrace expects that, at the start of a system call, %eax contains
* -ENOSYS, so this makes it so.
@@ -29,8 +30,8 @@
#define SC_START_SYSCALL(sc) do SC_RAX(sc) = -ENOSYS; while(0)
-#define SEGV_IS_FIXABLE(trap) ((trap) == 14)
-#define SC_SEGV_IS_FIXABLE(sc) SEGV_IS_FIXABLE(SC_TRAP_TYPE(sc))
+/* This is Page Fault */
+#define SEGV_IS_FIXABLE(fi) ((fi)->trap_no == 14)
extern unsigned long *sc_sigmask(void *sc_ptr);
diff --git a/arch/um/include/sysdep-x86_64/skas_ptrace.h b/arch/um/include/sysdep-x86_64/skas_ptrace.h
new file mode 100644
index 0000000..95db4be7
--- /dev/null
+++ b/arch/um/include/sysdep-x86_64/skas_ptrace.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __SYSDEP_X86_64_SKAS_PTRACE_H
+#define __SYSDEP_X86_64_SKAS_PTRACE_H
+
+struct ptrace_faultinfo {
+ int is_write;
+ unsigned long addr;
+};
+
+struct ptrace_ldt {
+ int func;
+ void *ptr;
+ unsigned long bytecount;
+};
+
+#define PTRACE_LDT 54
+
+#endif