/*
* Copyright (C) 2006 Jakub Jermar
* 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 <ddi/ddi.h>
#include <arch/ddi/ddi.h>
#include <proc/task.h>
#include <arch/types.h>
#include <typedefs.h>
#include <adt/bitmap.h>
#include <mm/slab.h>
#include <arch/pm.h>
#include <errno.h>
#include <arch/cpu.h>
#include <arch.h>
#include <align.h>
/** Enable I/O space range for task.
*
* Interrupts are disabled and task is locked.
*
* @param task Task.
* @param ioaddr Startign I/O space address.
* @param size Size of the enabled I/O range.
*
* @return 0 on success or an error code from errno.h.
*/
int ddi_iospace_enable_arch(task_t *task, __address ioaddr, size_t size)
{
count_t bits;
bits = ioaddr + size;
if (bits > IO_PORTS)
return ENOENT;
if (task->arch.iomap.bits < bits) {
bitmap_t oldiomap;
__u8 *newmap;
/*
* The I/O permission bitmap is too small and needs to be grown.
*/
newmap
= (__u8
*) malloc(BITS2BYTES
(bits
), FRAME_ATOMIC
);
if (!newmap)
return ENOMEM;
bitmap_initialize(&oldiomap, task->arch.iomap.map, task->arch.iomap.bits);
bitmap_initialize(&task->arch.iomap, newmap, bits);
/*
* Mark the new range inaccessible.
*/
bitmap_set_range(&task->arch.iomap, oldiomap.bits, bits - oldiomap.bits);
/*
* In case there really existed smaller iomap,
* copy its contents and deallocate it.
*/
if (oldiomap.bits) {
bitmap_copy(&task->arch.iomap, &oldiomap, oldiomap.bits);
}
}
/*
* Enable the range and we are done.
*/
bitmap_clear_range(&task->arch.iomap, (index_t) ioaddr, (count_t) size);
/*
* Increment I/O Permission bitmap generation counter.
*/
task->arch.iomapver++;
return 0;
}
/** Enable/disable interrupts form syscall
*
* @param enable If non-zero, interrupts are enabled, otherwise disabled
* @param flags RFLAGS register
*/
__native ddi_int_control_arch(__native enable, __native *flags)
{
if (enable)
*flags |= RFLAGS_IF;
else
*flags &= ~RFLAGS_IF;
return 0;
}
/** Install I/O Permission bitmap.
*
* Current task's I/O permission bitmap, if any, is installed
* in the current CPU's TSS.
*
* Interrupts must be disabled prior this call.
*/
void io_perm_bitmap_install(void)
{
count_t bits;
ptr_16_64_t cpugdtr;
descriptor_t *gdt_p;
tss_descriptor_t *tss_desc;
count_t ver;
/* First, copy the I/O Permission Bitmap. */
spinlock_lock(&TASK->lock);
ver = TASK->arch.iomapver;
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, ALIGN_UP(TASK->arch.iomap.bits, 8), 8);
}
spinlock_unlock(&TASK->lock);
/*
* Second, adjust TSS segment limit.
* Take the extra ending byte will all bits set into account.
*/
gdtr_store(&cpugdtr);
gdt_p = (descriptor_t *) cpugdtr.base;
gdt_tss_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits));
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));
/*
* Update the generation count so that faults caused by
* early accesses can be serviced.
*/
CPU->arch.iomapver_copy = ver;
}