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  1. /*
  2.  * Copyright (c) 2006 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup ia32ddi
  30.  * @{
  31.  */
  32. /** @file
  33.  */
  34.  
  35. #include <ddi/ddi.h>
  36. #include <arch/ddi/ddi.h>
  37. #include <proc/task.h>
  38. #include <arch/types.h>
  39. #include <adt/bitmap.h>
  40. #include <mm/slab.h>
  41. #include <arch/pm.h>
  42. #include <errno.h>
  43. #include <arch/cpu.h>
  44. #include <cpu.h>
  45. #include <arch.h>
  46. #include <align.h>
  47.  
  48. /** Enable I/O space range for task.
  49.  *
  50.  * Interrupts are disabled and task is locked.
  51.  *
  52.  * @param task Task.
  53.  * @param ioaddr Startign I/O space address.
  54.  * @param size Size of the enabled I/O range.
  55.  *
  56.  * @return 0 on success or an error code from errno.h.
  57.  */
  58. int ddi_iospace_enable_arch(task_t *task, uintptr_t ioaddr, size_t size)
  59. {
  60.     count_t bits;
  61.  
  62.     bits = ioaddr + size;
  63.     if (bits > IO_PORTS)
  64.         return ENOENT;
  65.  
  66.     if (task->arch.iomap.bits < bits) {
  67.         bitmap_t oldiomap;
  68.         uint8_t *newmap;
  69.    
  70.         /*
  71.          * The I/O permission bitmap is too small and needs to be grown.
  72.          */
  73.        
  74.         newmap = (uint8_t *) malloc(BITS2BYTES(bits), FRAME_ATOMIC);
  75.         if (!newmap)
  76.             return ENOMEM;
  77.        
  78.         bitmap_initialize(&oldiomap, task->arch.iomap.map, task->arch.iomap.bits);
  79.         bitmap_initialize(&task->arch.iomap, newmap, bits);
  80.  
  81.         /*
  82.          * Mark the new range inaccessible.
  83.          */
  84.         bitmap_set_range(&task->arch.iomap, oldiomap.bits, bits - oldiomap.bits);
  85.  
  86.         /*
  87.          * In case there really existed smaller iomap,
  88.          * copy its contents and deallocate it.
  89.          */    
  90.         if (oldiomap.bits) {
  91.             bitmap_copy(&task->arch.iomap, &oldiomap, oldiomap.bits);
  92.             free(oldiomap.map);
  93.         }
  94.     }
  95.  
  96.     /*
  97.      * Enable the range and we are done.
  98.      */
  99.     bitmap_clear_range(&task->arch.iomap, (index_t) ioaddr, (count_t) size);
  100.  
  101.     /*
  102.      * Increment I/O Permission bitmap generation counter.
  103.      */
  104.     task->arch.iomapver++;
  105.  
  106.     return 0;
  107. }
  108.  
  109. /** Install I/O Permission bitmap.
  110.  *
  111.  * Current task's I/O permission bitmap, if any, is installed
  112.  * in the current CPU's TSS.
  113.  *
  114.  * Interrupts must be disabled prior this call.
  115.  */
  116. void io_perm_bitmap_install(void)
  117. {
  118.     count_t bits;
  119.     ptr_16_32_t cpugdtr;
  120.     descriptor_t *gdt_p;
  121.     count_t ver;
  122.  
  123.     /* First, copy the I/O Permission Bitmap. */
  124.     spinlock_lock(&TASK->lock);
  125.     ver = TASK->arch.iomapver;
  126.     if ((bits = TASK->arch.iomap.bits)) {
  127.         bitmap_t iomap;
  128.    
  129.         ASSERT(TASK->arch.iomap.map);
  130.         bitmap_initialize(&iomap, CPU->arch.tss->iomap, TSS_IOMAP_SIZE * 8);
  131.         bitmap_copy(&iomap, &TASK->arch.iomap, TASK->arch.iomap.bits);
  132.         /*
  133.          * It is safe to set the trailing eight bits because of the extra
  134.          * convenience byte in TSS_IOMAP_SIZE.
  135.          */
  136.         bitmap_set_range(&iomap, ALIGN_UP(TASK->arch.iomap.bits, 8), 8);
  137.     }
  138.     spinlock_unlock(&TASK->lock);
  139.  
  140.     /*
  141.      * Second, adjust TSS segment limit.
  142.      * Take the extra ending byte with all bits set into account.
  143.      */
  144.     gdtr_store(&cpugdtr);
  145.     gdt_p = (descriptor_t *) cpugdtr.base;
  146.     gdt_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits));
  147.     gdtr_load(&cpugdtr);
  148.  
  149.     /*
  150.      * Before we load new TSS limit, the current TSS descriptor
  151.      * type must be changed to describe inactive TSS.
  152.      */
  153.     gdt_p[TSS_DES].access = AR_PRESENT | AR_TSS | DPL_KERNEL;
  154.     tr_load(selector(TSS_DES));
  155.    
  156.     /*
  157.      * Update the generation count so that faults caused by
  158.      * early accesses can be serviced.
  159.      */
  160.     CPU->arch.iomapver_copy = ver;
  161. }
  162.  
  163. /** @}
  164.  */
  165.