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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,
  79.             task->arch.iomap.bits);
  80.         bitmap_initialize(&task->arch.iomap, newmap, bits);
  81.  
  82.         /*
  83.          * Mark the new range inaccessible.
  84.          */
  85.         bitmap_set_range(&task->arch.iomap, oldiomap.bits,
  86.             bits - oldiomap.bits);
  87.  
  88.         /*
  89.          * In case there really existed smaller iomap,
  90.          * copy its contents and deallocate it.
  91.          */    
  92.         if (oldiomap.bits) {
  93.             bitmap_copy(&task->arch.iomap, &oldiomap,
  94.                 oldiomap.bits);
  95.             free(oldiomap.map);
  96.         }
  97.     }
  98.  
  99.     /*
  100.      * Enable the range and we are done.
  101.      */
  102.     bitmap_clear_range(&task->arch.iomap, (index_t) ioaddr, (count_t) size);
  103.  
  104.     /*
  105.      * Increment I/O Permission bitmap generation counter.
  106.      */
  107.     task->arch.iomapver++;
  108.  
  109.     return 0;
  110. }
  111.  
  112. /** Install I/O Permission bitmap.
  113.  *
  114.  * Current task's I/O permission bitmap, if any, is installed
  115.  * in the current CPU's TSS.
  116.  *
  117.  * Interrupts must be disabled prior this call.
  118.  */
  119. void io_perm_bitmap_install(void)
  120. {
  121.     count_t bits;
  122.     ptr_16_32_t cpugdtr;
  123.     descriptor_t *gdt_p;
  124.     count_t ver;
  125.  
  126.     /* First, copy the I/O Permission Bitmap. */
  127.     spinlock_lock(&TASK->lock);
  128.     ver = TASK->arch.iomapver;
  129.     if ((bits = TASK->arch.iomap.bits)) {
  130.         bitmap_t iomap;
  131.         task_t *task = TASK;
  132.    
  133.         ASSERT(TASK->arch.iomap.map);
  134.         bitmap_initialize(&iomap, CPU->arch.tss->iomap,
  135.             TSS_IOMAP_SIZE * 8);
  136.         bitmap_copy(&iomap, &task->arch.iomap, task->arch.iomap.bits);
  137.         /*
  138.          * It is safe to set the trailing eight bits because of the
  139.          * extra convenience byte in TSS_IOMAP_SIZE.
  140.          */
  141.         bitmap_set_range(&iomap, ALIGN_UP(TASK->arch.iomap.bits, 8), 8);
  142.     }
  143.     spinlock_unlock(&TASK->lock);
  144.  
  145.     /*
  146.      * Second, adjust TSS segment limit.
  147.      * Take the extra ending byte with all bits set into account.
  148.      */
  149.     gdtr_store(&cpugdtr);
  150.     gdt_p = (descriptor_t *) cpugdtr.base;
  151.     gdt_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits));
  152.     gdtr_load(&cpugdtr);
  153.  
  154.     /*
  155.      * Before we load new TSS limit, the current TSS descriptor
  156.      * type must be changed to describe inactive TSS.
  157.      */
  158.     gdt_p[TSS_DES].access = AR_PRESENT | AR_TSS | DPL_KERNEL;
  159.     tr_load(gdtselector(TSS_DES));
  160.    
  161.     /*
  162.      * Update the generation count so that faults caused by
  163.      * early accesses can be serviced.
  164.      */
  165.     CPU->arch.iomapver_copy = ver;
  166. }
  167.  
  168. /** @}
  169.  */
  170.