[ARM] 3110/5: old ABI compat: multi-ABI syscall entry support
Patch from Nicolas Pitre
This patch adds the required code to support both user space ABIs at
the same time. A second syscall table is created to include legacy ABI
syscalls that need an ABI compat wrapper.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S
index 8c0bf04..75e6f9a 100644
--- a/arch/arm/kernel/calls.S
+++ b/arch/arm/kernel/calls.S
@@ -13,7 +13,7 @@
#define NR_syscalls 328
#else
-__syscall_start:
+100:
/* 0 */ .long sys_restart_syscall
.long sys_exit
.long sys_fork_wrapper
@@ -27,7 +27,7 @@
/* 10 */ .long sys_unlink
.long sys_execve_wrapper
.long sys_chdir
- .long sys_time /* used by libc4 */
+ .long OBSOLETE(sys_time) /* used by libc4 */
.long sys_mknod
/* 15 */ .long sys_chmod
.long sys_lchown16
@@ -36,15 +36,15 @@
.long sys_lseek
/* 20 */ .long sys_getpid
.long sys_mount
- .long sys_oldumount /* used by libc4 */
+ .long OBSOLETE(sys_oldumount) /* used by libc4 */
.long sys_setuid16
.long sys_getuid16
-/* 25 */ .long sys_stime
+/* 25 */ .long OBSOLETE(sys_stime)
.long sys_ptrace
- .long sys_alarm /* used by libc4 */
+ .long OBSOLETE(sys_alarm) /* used by libc4 */
.long sys_ni_syscall /* was sys_fstat */
.long sys_pause
-/* 30 */ .long sys_utime /* used by libc4 */
+/* 30 */ .long OBSOLETE(sys_utime) /* used by libc4 */
.long sys_ni_syscall /* was sys_stty */
.long sys_ni_syscall /* was sys_getty */
.long sys_access
@@ -90,21 +90,21 @@
.long sys_sigpending
.long sys_sethostname
/* 75 */ .long sys_setrlimit
- .long sys_old_getrlimit /* used by libc4 */
+ .long OBSOLETE(sys_old_getrlimit) /* used by libc4 */
.long sys_getrusage
.long sys_gettimeofday
.long sys_settimeofday
/* 80 */ .long sys_getgroups16
.long sys_setgroups16
- .long old_select /* used by libc4 */
+ .long OBSOLETE(old_select) /* used by libc4 */
.long sys_symlink
.long sys_ni_syscall /* was sys_lstat */
/* 85 */ .long sys_readlink
.long sys_uselib
.long sys_swapon
.long sys_reboot
- .long old_readdir /* used by libc4 */
-/* 90 */ .long old_mmap /* used by libc4 */
+ .long OBSOLETE(old_readdir) /* used by libc4 */
+/* 90 */ .long OBSOLETE(old_mmap) /* used by libc4 */
.long sys_munmap
.long sys_truncate
.long sys_ftruncate
@@ -116,7 +116,7 @@
.long sys_statfs
/* 100 */ .long sys_fstatfs
.long sys_ni_syscall
- .long sys_socketcall
+ .long OBSOLETE(sys_socketcall)
.long sys_syslog
.long sys_setitimer
/* 105 */ .long sys_getitimer
@@ -127,11 +127,11 @@
/* 110 */ .long sys_ni_syscall /* was sys_iopl */
.long sys_vhangup
.long sys_ni_syscall
- .long sys_syscall /* call a syscall */
+ .long OBSOLETE(sys_syscall) /* call a syscall */
.long sys_wait4
/* 115 */ .long sys_swapoff
.long sys_sysinfo
- .long sys_ipc
+ .long OBSOLETE(ABI(sys_ipc, sys_oabi_ipc))
.long sys_fsync
.long sys_sigreturn_wrapper
/* 120 */ .long sys_clone_wrapper
@@ -194,8 +194,8 @@
.long sys_rt_sigtimedwait
.long sys_rt_sigqueueinfo
.long sys_rt_sigsuspend_wrapper
-/* 180 */ .long sys_pread64
- .long sys_pwrite64
+/* 180 */ .long ABI(sys_pread64, sys_oabi_pread64)
+ .long ABI(sys_pwrite64, sys_oabi_pwrite64)
.long sys_chown16
.long sys_getcwd
.long sys_capget
@@ -207,11 +207,11 @@
/* 190 */ .long sys_vfork_wrapper
.long sys_getrlimit
.long sys_mmap2
- .long sys_truncate64
- .long sys_ftruncate64
-/* 195 */ .long sys_stat64
- .long sys_lstat64
- .long sys_fstat64
+ .long ABI(sys_truncate64, sys_oabi_truncate64)
+ .long ABI(sys_ftruncate64, sys_oabi_ftruncate64)
+/* 195 */ .long ABI(sys_stat64, sys_oabi_stat64)
+ .long ABI(sys_lstat64, sys_oabi_lstat64)
+ .long ABI(sys_fstat64, sys_oabi_fstat64)
.long sys_lchown
.long sys_getuid
/* 200 */ .long sys_getgid
@@ -235,11 +235,11 @@
.long sys_pivot_root
.long sys_mincore
/* 220 */ .long sys_madvise
- .long sys_fcntl64
+ .long ABI(sys_fcntl64, sys_oabi_fcntl64)
.long sys_ni_syscall /* TUX */
.long sys_ni_syscall
.long sys_gettid
-/* 225 */ .long sys_readahead
+/* 225 */ .long ABI(sys_readahead, sys_oabi_readahead)
.long sys_setxattr
.long sys_lsetxattr
.long sys_fsetxattr
@@ -265,8 +265,8 @@
.long sys_exit_group
.long sys_lookup_dcookie
/* 250 */ .long sys_epoll_create
- .long sys_epoll_ctl
- .long sys_epoll_wait
+ .long ABI(sys_epoll_ctl, sys_oabi_epoll_ctl)
+ .long ABI(sys_epoll_wait, sys_oabi_epoll_wait)
.long sys_remap_file_pages
.long sys_ni_syscall /* sys_set_thread_area */
/* 255 */ .long sys_ni_syscall /* sys_get_thread_area */
@@ -312,7 +312,7 @@
/* 295 */ .long sys_getsockopt
.long sys_sendmsg
.long sys_recvmsg
- .long sys_semop
+ .long ABI(sys_semop, sys_oabi_semop)
.long sys_semget
/* 300 */ .long sys_semctl
.long sys_msgsnd
@@ -326,7 +326,7 @@
.long sys_add_key
/* 310 */ .long sys_request_key
.long sys_keyctl
- .long sys_semtimedop
+ .long ABI(sys_semtimedop, sys_oabi_semtimedop)
/* vserver */ .long sys_ni_syscall
.long sys_ioprio_set
/* 315 */ .long sys_ioprio_get
@@ -336,9 +336,8 @@
.long sys_mbind
/* 320 */ .long sys_get_mempolicy
.long sys_set_mempolicy
-__syscall_end:
- .rept NR_syscalls - (__syscall_end - __syscall_start) / 4
+ .rept NR_syscalls - (. - 100b) / 4
.long sys_ni_syscall
.endr
#endif
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 59ce1bc..8826d98 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -123,23 +123,49 @@
/*
* Get the system call number.
*/
-#if defined(CONFIG_AEABI)
- @ syscall number is in scno (r7) already.
+#if defined(CONFIG_OABI_COMPAT)
+ /*
+ * If we have CONFIG_OABI_COMPAT then we need to look at the swi
+ * value to determine if it is an EABI or an old ABI call.
+ */
+#ifdef CONFIG_ARM_THUMB
+ tst r8, #PSR_T_BIT
+ movne r10, #0 @ no thumb OABI emulation
+ ldreq r10, [lr, #-4] @ get SWI instruction
+#else
+ ldr r10, [lr, #-4] @ get SWI instruction
+ A710( and ip, r10, #0x0f000000 @ check for SWI )
+ A710( teq ip, #0x0f000000 )
+ A710( bne .Larm710bug )
+#endif
+
+#elif defined(CONFIG_AEABI)
+
+ /*
+ * Pure EABI user space always put syscall number into scno (r7).
+ */
A710( ldr ip, [lr, #-4] @ get SWI instruction )
A710( and ip, ip, #0x0f000000 @ check for SWI )
A710( teq ip, #0x0f000000 )
A710( bne .Larm710bug )
+
#elif defined(CONFIG_ARM_THUMB)
+
+ /* Legacy ABI only, possibly thumb mode. */
tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in
ldreq scno, [lr, #-4]
+
#else
+
+ /* Legacy ABI only. */
ldr scno, [lr, #-4] @ get SWI instruction
A710( and ip, scno, #0x0f000000 @ check for SWI )
A710( teq ip, #0x0f000000 )
A710( bne .Larm710bug )
+
#endif
#ifdef CONFIG_ALIGNMENT_TRAP
@@ -150,12 +176,24 @@
enable_irq
get_thread_info tsk
+ adr tbl, sys_call_table @ load syscall table pointer
ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing
-#ifndef CONFIG_AEABI
+
+#if defined(CONFIG_OABI_COMPAT)
+ /*
+ * If the swi argument is zero, this is an EABI call and we do nothing.
+ *
+ * If this is an old ABI call, get the syscall number into scno and
+ * get the old ABI syscall table address.
+ */
+ bics r10, r10, #0xff000000
+ eorne scno, r10, #__NR_OABI_SYSCALL_BASE
+ ldrne tbl, =sys_oabi_call_table
+#elif !defined(CONFIG_AEABI)
bic scno, scno, #0xff000000 @ mask off SWI op-code
eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
#endif
- adr tbl, sys_call_table @ load syscall table pointer
+
stmdb sp!, {r4, r5} @ push fifth and sixth args
tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls?
bne __sys_trace
@@ -200,10 +238,24 @@
__cr_alignment:
.word cr_alignment
#endif
+ .ltorg
+
+/*
+ * This is the syscall table declaration for native ABI syscalls.
+ * With EABI a couple syscalls are obsolete and defined as sys_ni_syscall.
+ */
+#define ABI(native, compat) native
+#ifdef CONFIG_AEABI
+#define OBSOLETE(syscall) sys_ni_syscall
+#else
+#define OBSOLETE(syscall) syscall
+#endif
.type sys_call_table, #object
ENTRY(sys_call_table)
#include "calls.S"
+#undef ABI
+#undef OBSOLETE
/*============================================================================
* Special system call wrappers
@@ -212,8 +264,7 @@
@ r8 = syscall table
.type sys_syscall, #function
sys_syscall:
-#ifndef CONFIG_AEABI
- eor scno, r0, #__NR_SYSCALL_BASE
+ eor scno, r0, #__NR_OABI_SYSCALL_BASE
cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
cmpne scno, #NR_syscalls @ check range
stmloia sp, {r5, r6} @ shuffle args
@@ -222,7 +273,6 @@
movlo r2, r3
movlo r3, r4
ldrlo pc, [tbl, scno, lsl #2]
-#endif
b sys_ni_syscall
sys_fork_wrapper:
@@ -290,6 +340,7 @@
#endif
#ifdef CONFIG_OABI_COMPAT
+
/*
* These are syscalls with argument register differences
*/
@@ -318,5 +369,18 @@
mov r2, r1
b sys_readahead
+/*
+ * Let's declare a second syscall table for old ABI binaries
+ * using the compatibility syscall entries.
+ */
+#define ABI(native, compat) compat
+#define OBSOLETE(syscall) syscall
+
+ .type sys_oabi_call_table, #object
+ENTRY(sys_oabi_call_table)
+#include "calls.S"
+#undef ABI
+#undef OBSOLETE
+
#endif
diff --git a/arch/arm/kernel/sys_arm.c b/arch/arm/kernel/sys_arm.c
index ea569ba..a491de2 100644
--- a/arch/arm/kernel/sys_arm.c
+++ b/arch/arm/kernel/sys_arm.c
@@ -147,6 +147,7 @@
return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}
+#if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT)
/*
* sys_ipc() is the de-multiplexer for the SysV IPC calls..
*
@@ -226,6 +227,7 @@
return -ENOSYS;
}
}
+#endif
/* Fork a new task - this creates a new program thread.
* This is called indirectly via a small wrapper
diff --git a/include/asm-arm/unistd.h b/include/asm-arm/unistd.h
index c9e087f..77430d6 100644
--- a/include/asm-arm/unistd.h
+++ b/include/asm-arm/unistd.h
@@ -514,22 +514,25 @@
#ifdef __KERNEL__
#define __ARCH_WANT_IPC_PARSE_VERSION
-#define __ARCH_WANT_OLD_READDIR
#define __ARCH_WANT_STAT64
-#define __ARCH_WANT_SYS_ALARM
#define __ARCH_WANT_SYS_GETHOSTNAME
#define __ARCH_WANT_SYS_PAUSE
-#define __ARCH_WANT_SYS_TIME
-#define __ARCH_WANT_SYS_UTIME
-#define __ARCH_WANT_SYS_SOCKETCALL
#define __ARCH_WANT_SYS_GETPGRP
#define __ARCH_WANT_SYS_LLSEEK
#define __ARCH_WANT_SYS_NICE
-#define __ARCH_WANT_SYS_OLD_GETRLIMIT
-#define __ARCH_WANT_SYS_OLDUMOUNT
#define __ARCH_WANT_SYS_SIGPENDING
#define __ARCH_WANT_SYS_SIGPROCMASK
#define __ARCH_WANT_SYS_RT_SIGACTION
+
+#if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT)
+#define __ARCH_WANT_SYS_TIME
+#define __ARCH_WANT_SYS_OLDUMOUNT
+#define __ARCH_WANT_SYS_ALARM
+#define __ARCH_WANT_SYS_UTIME
+#define __ARCH_WANT_SYS_OLD_GETRLIMIT
+#define __ARCH_WANT_OLD_READDIR
+#define __ARCH_WANT_SYS_SOCKETCALL
+#endif
#endif
#ifdef __KERNEL_SYSCALLS__