/*
* Copyright (C) 2005 Ondrej Palkovsky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 <proc/scheduler.h>
#include <cpu.h>
#include <proc/task.h>
#include <proc/thread.h>
#include <arch.h>
#include <arch/context.h> /* SP_DELTA */
#include <arch/asm.h>
#include <arch/debugger.h>
#include <print.h>
#include <arch/pm.h>
#include <adt/bitmap.h>
/** Perform amd64 specific tasks needed before the new task is run.
*
* Interrupts are disabled.
*/
void before_task_runs_arch(void)
{
count_t bits;
ptr_16_64_t cpugdtr;
descriptor_t *gdt_p;
tss_descriptor_t *tss_desc;
/*
* Switch the I/O Permission Bitmap, if necessary.
*/
/* First, copy the I/O Permission Bitmap. */
spinlock_lock(&TASK->lock);
if ((bits = TASK->arch.iomap.bits)) {
bitmap_t iomap;
ASSERT(TASK->arch.iomap.map);
bitmap_initialize(&iomap, CPU->arch.tss->iomap, TSS_IOMAP_SIZE * 8);
bitmap_copy(&iomap, &TASK->arch.iomap, TASK->arch.iomap.bits);
/*
* It is safe to set the trailing eight bits because of the extra
* convenience byte in TSS_IOMAP_SIZE.
*/
bitmap_set_range(&iomap, TASK->arch.iomap.bits, 8);
}
spinlock_unlock(&TASK->lock);
/* Second, adjust TSS segment limit. */
gdtr_store(&cpugdtr);
gdt_p = (descriptor_t *) cpugdtr.base;
gdt_tss_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits) - 1);
gdtr_load(&cpugdtr);
/*
* Before we load new TSS limit, the current TSS descriptor
* type must be changed to describe inactive TSS.
*/
tss_desc = (tss_descriptor_t *) &gdt_p[TSS_DES];
tss_desc->type = AR_TSS;
tr_load(gdtselector(TSS_DES));
}
/** Perform amd64 specific tasks needed before the new thread is scheduled. */
void before_thread_runs_arch(void)
{
CPU->arch.tss->rsp0 = (__address) &THREAD->kstack[THREAD_STACK_SIZE-SP_DELTA];
/* Syscall support - write address of thread stack pointer to
* hidden part of gs */
swapgs();
write_msr(AMD_MSR_GS, (__u64)&THREAD->kstack);
swapgs();
/* TLS support - set FS to thread local storage */
write_msr(AMD_MSR_FS, THREAD->arch.tls);
#ifdef CONFIG_DEBUG_AS_WATCHPOINT
/* Set watchpoint on AS to ensure that nobody sets it to zero */
if (CPU->id < BKPOINTS_MAX)
breakpoint_add(&((the_t *) THREAD->kstack)->as,
BKPOINT_WRITE | BKPOINT_CHECK_ZERO,
CPU->id);
#endif
}
void after_thread_ran_arch(void)
{
}