Changes in kernel/arch/amd64/src/ddi/ddi.c [6eeb4a3:9d58539] in mainline

File:

• kernel/arch/amd64/src/ddi/ddi.c (modified) (4 diffs)

kernel/arch/amd64/src/ddi/ddi.c

@@ -42 +42 @@
 #include <errno.h>
 #include <arch/cpu.h>
-#include <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, uintptr_t ioaddr, size_t size)
+{
+        size_t bits = ioaddr + size;
+        if (bits > IO_PORTS)
+                return ENOENT;
+        
+        if (task->arch.iomap.bits < bits) {
+                /*
+                 * The I/O permission bitmap is too small and needs to be grown.
+                 */
+                
+                uint8_t *newmap = (uint8_t *) malloc(BITS2BYTES(bits), FRAME_ATOMIC);
+                if (!newmap)
+                        return ENOMEM;
+                
+                bitmap_t oldiomap;
+                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);
+                        free(oldiomap.map);
+                }
+        }
+        
+        /*
+         * Enable the range and we are done.
+         */
+        bitmap_clear_range(&task->arch.iomap, (size_t) ioaddr, (size_t) size);
+        
+        /*
+         * Increment I/O Permission bitmap generation counter.
+         */
+        task->arch.iomapver++;
+        
+        return 0;
+}
 
 /** Install I/O Permission bitmap.
@@ -58 +118 @@
         /* First, copy the I/O Permission Bitmap. */
         irq_spinlock_lock(&TASK->lock, false);
-        
         size_t ver = TASK->arch.iomapver;
-        size_t elements = TASK->arch.iomap.elements;
-        
-        if (elements > 0) {
-                ASSERT(TASK->arch.iomap.bits);
+        size_t bits = TASK->arch.iomap.bits;
+        if (bits) {
+                ASSERT(TASK->arch.iomap.map);
                 
                 bitmap_t iomap;
-                bitmap_initialize(&iomap, TSS_IOMAP_SIZE * 8,
-                    CPU->arch.tss->iomap);
-                bitmap_copy(&iomap, &TASK->arch.iomap, elements);
+                bitmap_initialize(&iomap, CPU->arch.tss->iomap,
+                    TSS_IOMAP_SIZE * 8);
+                bitmap_copy(&iomap, &TASK->arch.iomap, bits);
                 
                 /*
@@ -74 +132 @@
                  * I/O access.
                  */
-                bitmap_set_range(&iomap, elements,
-                    ALIGN_UP(elements, 8) - elements);
-                
+                bitmap_set_range(&iomap, bits, ALIGN_UP(bits, 8) - 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(elements, 8), 8);
+                bitmap_set_range(&iomap, ALIGN_UP(bits, 8), 8);
         }
-        
         irq_spinlock_unlock(&TASK->lock, false);
         
         /*
          * Second, adjust TSS segment limit.
-         * Take the extra ending byte with all bits set into account.
+         * Take the extra ending byte will all bits set into account. 
          */
         ptr_16_64_t cpugdtr;
@@ -94 +149 @@
         
         descriptor_t *gdt_p = (descriptor_t *) cpugdtr.base;
-        size_t size = bitmap_size(elements);
-        gdt_tss_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + size);
+        gdt_tss_setlimit(&gdt_p[TSS_DES], TSS_BASIC_SIZE + BITS2BYTES(bits));
         gdtr_load(&cpugdtr);