151 lines
5.4 KiB
ArmAsm
151 lines
5.4 KiB
ArmAsm
/*
|
|
* Copyright (c) 2002 Jonathan Mini <mini@freebsd.org>.
|
|
* Copyright (c) 2001 Daniel Eischen <deischen@freebsd.org>.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Neither the name of the author nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY DANIEL EISCHEN AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <machine/asm.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
/*
|
|
* Where do we define these?
|
|
*/
|
|
#define MC_SIZE 640 /* sizeof mcontext_t */
|
|
#define UC_MC_OFFSET 16 /* offset to mcontext from ucontext */
|
|
#define UC_MC_LEN_OFFSET 96 /* offset to mc_len from mcontext */
|
|
#define MC_LEN_OFFSET 80 /* offset to mc_len from mcontext */
|
|
#define MC_FP_REGS_OFFSET 96 /* offset to FP regs from mcontext */
|
|
#define MC_FP_CW_OFFSET 96 /* offset to FP control word */
|
|
#define MC_OWNEDFP_OFFSET 88 /* offset to mc_ownedfp from mcontext */
|
|
#define KM_STACK_SP_OFFSET 32 /* offset to km_stack.ss_sp */
|
|
#define KM_STACK_SIZE_OFFSET 36 /* offset to km_stack.ss_sp */
|
|
#define KM_FUNC_OFFSET 28 /* offset to km_func */
|
|
|
|
/*
|
|
* int uts_to_thread(struct kse_thr_mailbox *tdp,
|
|
* struct kse_thr_mailbox **curthreadp);
|
|
*
|
|
* Does not return on success, returns -1 otherwise.
|
|
*/
|
|
ENTRY(uts_to_thread)
|
|
movl 4(%esp), %edx /* get address of kse_thr_mailbox */
|
|
/* .. ucontext_t is at offset 0 */
|
|
cmpl $0, %edx /* check for null pointer */
|
|
jne 1f
|
|
movl $-1, %eax
|
|
jmp 5f
|
|
1: cmpl $MC_SIZE, UC_MC_LEN_OFFSET(%edx) /* is context valid? */
|
|
je 2f
|
|
movl $-1, %eax /* bzzzt, invalid context */
|
|
jmp 5f
|
|
2: movl 8(%esp), %eax /* get address of curthreadp */
|
|
movl %edx, (%eax) /* we're now the current thread */
|
|
/*
|
|
* From here on, we don't touch the old stack.
|
|
*/
|
|
addl $UC_MC_OFFSET, %edx /* add offset to mcontext */
|
|
movl 4(%edx), %gs
|
|
movl 8(%edx), %fs
|
|
movl 12(%edx), %es
|
|
movl 16(%edx), %ds
|
|
movl 76(%edx), %ss
|
|
movl 20(%edx), %edi
|
|
movl 24(%edx), %esi
|
|
movl 28(%edx), %ebp
|
|
movl 72(%edx), %esp /* switch to context defined stack */
|
|
subl $4, %esp /* leave space for the return address */
|
|
movl 60(%edx), %eax /* put return address at top of stack */
|
|
movl %eax, (%esp)
|
|
cmpl $0, MC_OWNEDFP_OFFSET(%edx) /* are FP regs valid? */
|
|
jz 3f
|
|
frstor MC_FP_REGS_OFFSET(%edx) /* restore FP regs */
|
|
jmp 4f
|
|
3: fninit
|
|
fldcw MC_FP_CW_OFFSET(%edx)
|
|
4: movl 48(%edx), %eax /* restore ax, bx, cx */
|
|
movl 36(%edx), %ebx
|
|
movl 44(%edx), %ecx
|
|
pushl 68(%edx) /* flags on stack */
|
|
pushl 40(%edx) /* %edx on stack */
|
|
popl %edx /* %edx off stack */
|
|
popf /* flags off stack */
|
|
5: ret /* %eip off stack */
|
|
|
|
/*
|
|
* int thread_to_uts(struct kse_thr_mailbox *tm, struct kse_mailbox *km);
|
|
*
|
|
* Does not return on success, returns -1 otherwise.
|
|
*/
|
|
ENTRY(thread_to_uts)
|
|
movl 4(%esp), %eax /* get address of context */
|
|
cmpl $0, %eax /* check for null pointer */
|
|
jne 1f
|
|
movl $-1, %eax
|
|
jmp 2f
|
|
1: pushl %edx /* save value of edx */
|
|
movl %eax, %edx /* get address of context */
|
|
addl $UC_MC_OFFSET, %edx /* add offset to mcontext */
|
|
movl %gs, 4(%edx)
|
|
movl %fs, 8(%edx)
|
|
movl %es, 12(%edx)
|
|
movl %ds, 16(%edx)
|
|
movl %edi, 20(%edx)
|
|
movl %esi, 24(%edx)
|
|
movl %ebp, 28(%edx)
|
|
movl %ebx, 36(%edx)
|
|
movl $0, 48(%edx) /* store successful return in eax */
|
|
popl %eax /* get saved value of edx */
|
|
movl %eax, 40(%edx) /* save edx */
|
|
movl %ecx, 44(%edx)
|
|
movl (%esp), %eax /* get return address */
|
|
movl %eax, 60(%edx) /* save return address */
|
|
movl %ss, 76(%edx)
|
|
/*
|
|
* Don't save floating point registers here.
|
|
*
|
|
* This is an explicit call to get the current context, so
|
|
* the caller is done with the floating point registers.
|
|
* Contexts formed by involuntary switches, such as signal delivery,
|
|
* have floating point registers saved by the kernel.
|
|
*/
|
|
fnstcw MC_FP_CW_OFFSET(%edx)
|
|
movl $0, MC_OWNEDFP_OFFSET(%edx) /* no FP */
|
|
lahf /* get eflags */
|
|
movl %eax, 68(%edx) /* store eflags */
|
|
movl %esp, %eax /* setcontext pushes the return */
|
|
addl $4, %eax /* address onto the top of the */
|
|
movl %eax, 72(%edx) /* stack; account for this */
|
|
movl $MC_SIZE, MC_LEN_OFFSET(%edx) /* context is now valid */
|
|
movl 8(%esp), %edx /* get address of mailbox */
|
|
movl KM_STACK_SP_OFFSET(%edx), %eax /* get bottom of stack */
|
|
addl KM_STACK_SIZE_OFFSET(%edx), %eax /* add length */
|
|
movl %eax, %esp /* switch to the uts's stack */
|
|
pushl %edx /* push the address of the mailbox */
|
|
pushl KM_FUNC_OFFSET(%edx) /* .. the uts can return to itself */
|
|
pushl KM_FUNC_OFFSET(%edx) /* push the address of the uts func */
|
|
2: ret
|
|
|