freebsd-skq/sys/amd64/linux32/linux32_locore.s
Konstantin Belousov 2c66cccab7 Save and restore segment registers on amd64 when entering and leaving
the kernel on amd64. Fill and read segment registers for mcontext and
signals. Handle traps caused by restoration of the
invalidated selectors.

Implement user-mode creation and manipulation of the process-specific
LDT descriptors for amd64, see sysarch(2).

Implement support for TSS i/o port access permission bitmap for amd64.

Context-switch LDT and TSS. Do not save and restore segment registers on
the context switch, that is handled by kernel enter/leave trampolines
now. Remove segment restore code from the signal trampolines for
freebsd/amd64, freebsd/ia32 and linux/i386 for the same reason.

Implement amd64-specific compat shims for sysarch.

Linuxolator (temporary ?) switched to use gsbase for thread_area pointer.

TODO:
Currently, gdb is not adapted to show segment registers from struct reg.
Also, no machine-depended ptrace command is added to set segment
registers for debugged process.

In collaboration with:	pho
Discussed with:	peter
Reviewed by:	jhb
Linuxolator tested by:	dchagin
2009-04-01 13:09:26 +00:00

39 lines
1.0 KiB
ArmAsm

/* $FreeBSD$ */
#include "linux32_assym.h" /* system definitions */
#include <machine/asmacros.h> /* miscellaneous asm macros */
#include <amd64/linux32/linux32_syscall.h> /* system call numbers */
.text
.code32
NON_GPROF_ENTRY(linux_sigcode)
call *LINUX_SIGF_HANDLER(%esp)
leal LINUX_SIGF_SC(%esp),%ebx /* linux scp */
movl %esp, %ebx /* pass sigframe */
push %eax /* fake ret addr */
movl $LINUX_SYS_linux_sigreturn,%eax /* linux_sigreturn() */
int $0x80 /* enter kernel with args */
0: jmp 0b
ALIGN_TEXT
/* XXXXX */
linux_rt_sigcode:
call *LINUX_RT_SIGF_HANDLER(%esp)
leal LINUX_RT_SIGF_UC(%esp),%ebx /* linux ucp */
leal LINUX_RT_SIGF_SC(%ebx),%ecx /* linux sigcontext */
push %eax /* fake ret addr */
movl $LINUX_SYS_linux_rt_sigreturn,%eax /* linux_rt_sigreturn() */
int $0x80 /* enter kernel with args */
0: jmp 0b
ALIGN_TEXT
/* XXXXX */
linux_esigcode:
.data
.globl linux_szsigcode, linux_sznonrtsigcode
linux_szsigcode:
.long linux_esigcode-linux_sigcode
linux_sznonrtsigcode:
.long linux_rt_sigcode-linux_sigcode