diff options
Diffstat (limited to 'tools/KSE/rr/kse_asm.S')
-rw-r--r-- | tools/KSE/rr/kse_asm.S | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/tools/KSE/rr/kse_asm.S b/tools/KSE/rr/kse_asm.S new file mode 100644 index 0000000..20dc1db --- /dev/null +++ b/tools/KSE/rr/kse_asm.S @@ -0,0 +1,157 @@ +/* + * 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 36 /* offset to km_stack.ss_sp */ +#define KM_STACK_SIZE_OFFSET 40 /* offset to km_stack.ss_sp */ +#define KM_FUNC_OFFSET 32 /* 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), %ecx /* get address of curthreadp */ + movl %edx, %ebx /* save the pointer for later */ + /* + * 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, dx */ + pushl 68(%edx) /* flags on stack */ + pushl 36(%edx) /* %ebx on stack */ + pushl 44(%edx) /* %ecx on stack */ + movl 40(%edx), %edx /* %edx */ + /* + * all registers are now moved out of mailbox, + * it's safe to set current thread pointer + */ + movl %ebx,(%ecx) + popl %ecx /* %ecx off stack */ + pop %ebx /* %ebx 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 */ + pushfl /* get eflags */ + popl %eax + 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 + |