WebSVN – HelenOS – Diff – /kernel/trunk/generic/src/mm/frame.c

 /*
  * Copyright (C) 2001-2004 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 <arch/types.h>
 #include <func.h>
 #include <mm/heap.h>
 #include <mm/frame.h>
 #include <mm/page.h>
 #include <mm/vm.h>
 #include <arch/mm/page.h>
 #include <config.h>
 #include <memstr.h>
 #include <panic.h>
 #include <synch/spinlock.h>
 count_t frames = 0;
 count_t frames_free;
 __u8 *frame_bitmap;
 count_t frame_bitmap_octets;
-/*
- * This is for kernel address space frames (allocated with FRAME_KA).
- * Their addresses may not interfere with user address space.
- */
-__u8 *frame_kernel_bitmap;
-count_t kernel_frames;
-count_t kernel_frames_free;
 static spinlock_t framelock;
 void frame_init(void)
+{
         if (config.cpu_active == 1) {
                 /*
                  * The bootstrap processor will allocate all necessary memory for frame allocation.
                  */
                 frames = config.memory_size / FRAME_SIZE;
                 frame_bitmap_octets = frames / 8 + (frames % 8 > 0);
                 frame_bitmap = (__u8 *) malloc(frame_bitmap_octets);
                 if (!frame_bitmap)
                         panic("malloc/frame_bitmap\n");
                 /*
                  * Mark all frames free.
                  */
                 memsetb((__address) frame_bitmap, frame_bitmap_octets, 0);
                 frames_free = frames;
-        /*
-         * Will be properly set up by architecture dependent frame init.
-         */
-        frame_kernel_bitmap = NULL;
-        kernel_frames_free = 0;
-        kernel_frames = 0;
+    }
     /*
-     * No frame allocations/reservations  prior this point.
+     * No frame allocations/reservations prior this point.
      */
     frame_arch_init();
     if (config.cpu_active == 1) {
                 /*
                  * Create the memory address space map. Marked frames and frame
                  * regions cannot be used for allocation.
                  */
         frame_region_not_free(config.base, config.base + config.kernel_size);
+    }
+}
 /*
  * Allocate a frame.
  */
 __address frame_alloc(int flags)
+{
     int i;
     pri_t pri;
-    __u8 **frame_bitmap_ptr = &frame_bitmap;
-    count_t *frames_ptr = &frames, *frames_free_ptr = &frames_free;
-    if (flags & FRAME_KA) {
-        frame_bitmap_ptr = &frame_kernel_bitmap;
-        frames_ptr = &kernel_frames;
-        frames_free_ptr = &kernel_frames_free;
-    }
 loop:
     pri = cpu_priority_high();
     spinlock_lock(&framelock);
-    if (*frames_free_ptr) {
+    if (frames_free) {
-        for (i=0; i < *frames_ptr; i++) {
+        for (i=0; i < frames; i++) {
             int m, n;
             m = i / 8;
             n = i % 8;
-            if (((*frame_bitmap_ptr)[m] & (1<<n)) == 0) {
+            if ((frame_bitmap[m] & (1<<n)) == 0) {
-                (*frame_bitmap_ptr)[m] |= (1<<n);
+                frame_bitmap[m] |= (1<<n);
-                *frames_free_ptr--;
-                if (flags & FRAME_KA) {
-                    /*
-                     * frames_free_ptr points to kernel_frames_free
-                     * It is still necessary to decrement frames_free.
-                     */
-                    frames_free--;
+                frames_free--;
-                }
                 spinlock_unlock(&framelock);
                 cpu_priority_restore(pri);
                 if (flags & FRAME_KA) return PA2KA(i*FRAME_SIZE);
                 return i*FRAME_SIZE;
+            }
+        }
         panic("frames_free inconsistent (%d)\n", frames_free);
+    }
     spinlock_unlock(&framelock);
     cpu_priority_restore(pri);
     if (flags & FRAME_PANIC)
         panic("unable to allocate frame\n");
     /* TODO: implement sleeping logic here */
     panic("sleep not supported\n");
     goto loop;
+}
 /*
  * Free a frame.
  */
 void frame_free(__address addr)
+{
     pri_t pri;
     __u32 frame;
-    count_t *frames_free_ptr = &frames_free, *frames_ptr = &frames;
-    __u8 **frame_bitmap_ptr = &frame_bitmap;
-    if (IS_KA(addr)) {
-        frames_free_ptr = &kernel_frames_free;
-        frame_bitmap_ptr = &frame_kernel_bitmap;
-    }
     pri = cpu_priority_high();
     spinlock_lock(&framelock);
     frame = IS_KA(addr) ? KA2PA(addr) : addr;
     frame /= FRAME_SIZE;
-    if (frame < *frames_ptr) {
+    if (frame < frames) {
         int m, n;
         m = frame / 8;
         n = frame % 8;
-        if ((*frame_bitmap_ptr)[m] & (1<<n)) {
+        if (frame_bitmap[m] & (1<<n)) {
-            (*frame_bitmap_ptr)[m] &= ~(1<<n);
+            frame_bitmap[m] &= ~(1<<n);
-            *frames_free_ptr++;
-            if (IS_KA(addr)) {
-                /*
-                 * frames_free_ptr points to kernel_frames_free
-                 * It is still necessary to increment frames_free.
-                 */
-                 frames_free++;
+            frames_free++;
-            }
+        }
         else panic("frame already free\n");
+    }
     else panic("frame number too big\n");
     spinlock_unlock(&framelock);
     cpu_priority_restore(pri);
+}
 /*
  * Don't use this function for normal allocation. Use frame_alloc() instead.
  * Use this function to declare that some special frame is not free.
  */
 void frame_not_free(__address addr)
+{
     pri_t pri;
     __u32 frame;
-    count_t *frames_ptr = &frames, *frames_free_ptr = &frames_free;
-    __u8 **frame_bitmap_ptr = &frame_bitmap;
     pri = cpu_priority_high();
     spinlock_lock(&framelock);
     frame = IS_KA(addr) ? KA2PA(addr) : addr;
     frame /= FRAME_SIZE;
-    if (frame < *frames_ptr) {
+    if (frame < frames) {
         int m, n;
         m = frame / 8;
         n = frame % 8;
-        if (((*frame_bitmap_ptr)[m] & (1<<n)) == 0) {
+        if ((frame_bitmap[m] & (1<<n)) == 0) {
-            (*frame_bitmap_ptr)[m] |= (1<<n);
+            frame_bitmap[m] |= (1<<n);
-            *frames_free_ptr--;
-            if (IS_KA(addr)) {
-                /*
-                 * frames_free_ptr points to kernel_frames_free
-                 * It is still necessary to decrement frames_free.
-                 */
-                frames_free--;
+            frames_free--;
-            }
+        }
+    }
     spinlock_unlock(&framelock);
     cpu_priority_restore(pri);
+}
 void frame_region_not_free(__address start, __address stop)
+{
     __u32 i;
     start /= FRAME_SIZE;
     stop /= FRAME_SIZE;
     for (i = start; i <= stop; i++)
         frame_not_free(i * FRAME_SIZE);
+}

Subversion Repositories HelenOS

(root)/kernel/trunk/generic/src/mm/frame.c @ 776 – Rev 102 → 113