contiki/cpu/x86/mm/tss-prot-domains.c

162 lines
5.9 KiB
C
Raw Normal View History

/*
* Copyright (C) 2015-2016, 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.
*/
#include <stdint.h>
#include <string.h>
#include "gdt.h"
#include "helpers.h"
#include "idt.h"
#include "prot-domains.h"
#include "stacks.h"
#include "syscalls.h"
#include "tss.h"
uint32_t prot_domains_main_esp;
syscalls_entrypoint_t ATTR_KERN_ADDR_SPACE *prot_domains_syscall;
/*---------------------------------------------------------------------------*/
void app_main(void);
void
prot_domains_reg(dom_client_data_t ATTR_KERN_ADDR_SPACE *dcd,
uintptr_t mmio, size_t mmio_sz,
uintptr_t meta, size_t meta_sz,
bool pio)
{
segment_desc_t desc;
uint32_t eflags;
dom_id_t dom_id;
volatile struct dom_kern_data ATTR_KERN_ADDR_SPACE *dkd;
KERN_READL(dom_id, dcd->dom_id);
dkd = prot_domains_kern_data + dom_id;
prot_domains_reg_multi_seg(dkd, mmio, mmio_sz, meta, meta_sz);
/* Only the kernel protection domain requires port I/O access outside of the
* interrupt handlers.
*/
eflags = EFLAGS_IOPL(pio ? PRIV_LVL_USER : PRIV_LVL_INT);
if(dom_id == DOM_ID_app) {
eflags |= EFLAGS_IF;
}
/* Keep this initialization in sync with the register definitions in
* tss-prot-domains-asm.S.
*/
KERN_WRITEL(dkd->tss.ebp, 0);
KERN_WRITEL(dkd->tss.ebx, 0);
KERN_WRITEL(dkd->tss.esi, BIT(dom_id));
KERN_WRITEL(dkd->tss.eip,
(dom_id == DOM_ID_app) ?
(uint32_t)app_main :
(uint32_t)prot_domains_syscall_dispatcher);
KERN_WRITEL(dkd->tss.cs, GDT_SEL_CODE);
KERN_WRITEL(dkd->tss.ds, GDT_SEL_DATA);
KERN_WRITEL(dkd->tss.es, GDT_SEL_DATA);
KERN_WRITEL(dkd->tss.fs, LDT_SEL_KERN);
KERN_WRITEL(dkd->tss.gs,
(meta_sz == 0) ? GDT_SEL_NULL : LDT_SEL_META);
KERN_WRITEL(dkd->tss.ss, GDT_SEL_STK);
/* This stack pointer is only actually used in application protection domain.
* Other domains enter at system call dispatcher, which switches to main
* stack.
*/
KERN_WRITEL(dkd->tss.esp,
/* Two return addresses have been consumed: */
STACKS_INIT_TOP + (2 * sizeof(uintptr_t)));
KERN_WRITEL(dkd->tss.eflags, eflags);
KERN_WRITEL(dkd->tss.ldt, GDT_SEL_LDT(dom_id));
KERN_WRITEL(dkd->tss.esp2, STACKS_SIZE_MAIN + STACKS_SIZE_INT);
KERN_WRITEL(dkd->tss.ss2, GDT_SEL_STK_INT);
KERN_WRITEL(dkd->tss.esp0,
STACKS_SIZE_MAIN + STACKS_SIZE_INT + STACKS_SIZE_EXC);
KERN_WRITEL(dkd->tss.ss0, GDT_SEL_STK_EXC);
KERN_WRITEW(dkd->tss.t, 0);
KERN_WRITEW(dkd->tss.iomap_base, sizeof(tss_t));
KERN_WRITEL(dkd->tss.cr3, 0);
segment_desc_init(&desc,
KERN_DATA_OFF_TO_PHYS_ADDR((uint32_t)&(dkd->tss)),
sizeof(dkd->tss),
/* It should be possible for code at any privilege level to invoke the task's
* system call dispatcher.
*/
SEG_FLAG(DPL, PRIV_LVL_USER) | SEG_TYPE_TSS32_AVAIL);
gdt_insert(GDT_IDX_TSS(dom_id), desc);
KERN_WRITEW(dcd->tss_sel, GDT_SEL(GDT_IDX_TSS(dom_id), PRIV_LVL_USER));
}
/*---------------------------------------------------------------------------*/
void dev_not_avail_isr(void);
void
prot_domains_impl_init(void)
{
__asm__ __volatile__ ("ltr %0" :: "r" ((uint16_t)GDT_SEL_TSS(DOM_ID_kern)));
__asm__ __volatile__ ("lldt %0" :: "r" ((uint16_t)GDT_SEL_LDT(DOM_ID_kern)));
idt_set_intr_gate_desc(7,
(uint32_t)dev_not_avail_isr,
GDT_SEL_CODE_EXC, PRIV_LVL_EXC);
}
/*---------------------------------------------------------------------------*/
int main();
void
prot_domains_launch_kernel(void)
{
multi_segment_launch_kernel();
/* Activate kernel protection domain, entering the kernel at main. */
__asm__ __volatile__ (
"pushl %[_ss_]\n\t"
"pushl %[_top_of_stk_]\n\t"
"pushl %[_eflags_]\n\t"
"pushl %[_cs_]\n\t"
"pushl %[_kern_start_]\n\t"
"iretl\n\t"
:
: [_ss_] "g" (GDT_SEL_STK),
[_eflags_] "g" (EFLAGS_IOPL(PRIV_LVL_USER)),
[_cs_] "g" (GDT_SEL_CODE),
[_kern_start_] "g" (main),
/* one address has already been consumed */
[_top_of_stk_] "g" (STACKS_INIT_TOP + sizeof(uint32_t))
);
}
/*---------------------------------------------------------------------------*/
void
prot_domains_launch_app()
{
far_pointer_t app_ptr = { 0, GDT_SEL_TSS(DOM_ID_app) };
__asm__ __volatile__ ("ljmp *%0" :: "m" (app_ptr));
}
/*---------------------------------------------------------------------------*/