nes-proj/drivers/cpu/x86/mm/tss-prot-domains-asm.S

89 lines
3.4 KiB
ArmAsm

/*
* Copyright (C) 2015, Intel Corporation. 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder 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 THE COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDER 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.
*/
.text
/* Initialize the TSS fields in prot_domains_reg accordingly:
* Note: Each of these must be a callee-saved register, so that they are
* restored to their original values prior to the task returning. This will
* result in the same values being loaded when the task is next invoked.
*/
#define CUR_DOM_ID_BITMAP esi
/* Must match SEG_KERN (plus the trailing 's') in multi-segment.h */
#define SEG_KERN fs
.global prot_domains_syscall_dispatcher
prot_domains_syscall_dispatcher:
#define PROT_DOMAINS_SYSCALL eax
mov prot_domains_syscall, %PROT_DOMAINS_SYSCALL
cmp $syscalls_entrypoints, %PROT_DOMAINS_SYSCALL
jl halt
cmp $syscalls_entrypoints_end, %PROT_DOMAINS_SYSCALL
jnl halt
#define SYSCALLS_ENTRYPOINTS_ALIGN_MASK ebp
mov $3, %SYSCALLS_ENTRYPOINTS_ALIGN_MASK
and %PROT_DOMAINS_SYSCALL, %SYSCALLS_ENTRYPOINTS_ALIGN_MASK
jnz halt
/* Compare allowed domains bitmask against current domain ID bitmap. If
* the check fails, then the current domain ID bitmap value will be zeroed
* out, which could cause incorrect behavior in the future. However, the
* response to a failed check is to halt the system, so destroying the
* current domain ID bitmap value will have no effect.
*/
and %SEG_KERN:4(%PROT_DOMAINS_SYSCALL), %CUR_DOM_ID_BITMAP
jz halt
mov prot_domains_main_esp, %esp
/* Must be a callee-saved register: */
#define ORIG_RET_ADDR edi
/* Update the caller's stack to return back to here */
pop %ORIG_RET_ADDR
push $sysret_dispatcher
/* Jump to the system call body */
jmp *%SEG_KERN:(%PROT_DOMAINS_SYSCALL)
sysret_dispatcher:
push %ORIG_RET_ADDR
iret
/* The task will resume here for the next system call, so it is necessary
* to jump back to the top.
*/
jmp prot_domains_syscall_dispatcher
.global dev_not_avail_isr
dev_not_avail_isr:
clts
iret