arm: shorten syscall table for EABI - no point in storing NULL entries
Also, reformatted ARM code in get_scno(), mostly improved comments,
without code changes.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/linux/arm/signalent1.h b/linux/arm/signalent1.h
index c927d72..130972b 100644
--- a/linux/arm/signalent1.h
+++ b/linux/arm/signalent1.h
@@ -1,2 +1,2 @@
-/* i386 personality */
+/* "ARM specific syscall" personality */
#include "../signalent.h"
diff --git a/linux/arm/syscallent.h b/linux/arm/syscallent.h
index e3de1f5..53c01a8 100644
--- a/linux/arm/syscallent.h
+++ b/linux/arm/syscallent.h
@@ -406,6 +406,8 @@
{ 2, TD, sys_setns, "setns" }, /* 375 */
{ 6, 0, sys_process_vm_readv, "process_vm_readv" }, /* 376 */
{ 6, 0, sys_process_vm_writev, "process_vm_writev" }, /* 377 */
+
+#ifndef __ARM_EABI__
{ 5, 0, NULL, NULL }, /* 378 */
{ 5, 0, NULL, NULL }, /* 379 */
{ 5, 0, NULL, NULL }, /* 380 */
@@ -428,8 +430,6 @@
{ 5, 0, NULL, NULL }, /* 397 */
{ 5, 0, NULL, NULL }, /* 398 */
{ 5, 0, NULL, NULL }, /* 399 */
-
-#ifndef __ARM_EABI__
#if SYS_socket_subcall != 400
#error fix me
#endif
diff --git a/syscall.c b/syscall.c
index 158fe89..7e2d0e8 100644
--- a/syscall.c
+++ b/syscall.c
@@ -1215,59 +1215,43 @@
break;
}
#elif defined(ARM)
- /*
- * We only need to grab the syscall number on syscall entry.
- */
- if (arm_regs.ARM_ip == 0) {
- /*
- * Note: we only deal with 32-bit CPUs here
- */
- if (arm_regs.ARM_cpsr & 0x20) {
- /*
- * Get the Thumb-mode system call number
- */
- scno = arm_regs.ARM_r7;
- } else {
- /*
- * Get the ARM-mode system call number
- */
- errno = 0;
- scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
- if (errno)
- return -1;
-
- /* Handle the EABI syscall convention. We do not
- bother converting structures between the two
- ABIs, but basic functionality should work even
- if strace and the traced program have different
- ABIs. */
- if (scno == 0xef000000) {
- scno = arm_regs.ARM_r7;
- } else {
- if ((scno & 0x0ff00000) != 0x0f900000) {
- fprintf(stderr, "syscall: unknown syscall trap 0x%08lx\n",
- scno);
- return -1;
- }
-
- /*
- * Fixup the syscall number
- */
- scno &= 0x000fffff;
- }
- }
- if (scno & 0x0f0000) {
- /*
- * Handle ARM specific syscall
- */
- update_personality(tcp, 1);
- scno &= 0x0000ffff;
- } else
- update_personality(tcp, 0);
-
- } else {
- fprintf(stderr, "pid %d stray syscall entry\n", tcp->pid);
+ if (arm_regs.ARM_ip != 0) {
+ /* It is not a syscall entry */
+ fprintf(stderr, "pid %d stray syscall exit\n", tcp->pid);
tcp->flags |= TCB_INSYSCALL;
+ return 0;
+ }
+ /* Note: we support only 32-bit CPUs, not 26-bit */
+
+ if (arm_regs.ARM_cpsr & 0x20) {
+ /* Thumb mode */
+ scno = arm_regs.ARM_r7;
+ } else {
+ /* ARM mode */
+ errno = 0;
+ scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
+ if (errno)
+ return -1;
+
+ /* EABI syscall convention? */
+ if (scno == 0xef000000) {
+ scno = arm_regs.ARM_r7; /* yes */
+ } else {
+ if ((scno & 0x0ff00000) != 0x0f900000) {
+ fprintf(stderr, "pid %d unknown syscall trap 0x%08lx\n",
+ tcp->pid, scno);
+ return -1;
+ }
+ /* Fixup the syscall number */
+ scno &= 0x000fffff;
+ }
+ }
+ if (scno & 0x000f0000) {
+ /* ARM specific syscall. We handle it as a separate "personality" */
+ update_personality(tcp, 1);
+ scno &= 0x0000ffff;
+ } else {
+ update_personality(tcp, 0);
}
#elif defined(M68K)
if (upeek(tcp, 4*PT_ORIG_D0, &scno) < 0)