auto import from //depot/cupcake/@135843
diff --git a/linker/ba.c b/linker/ba.c
new file mode 100644
index 0000000..bea6f84
--- /dev/null
+++ b/linker/ba.c
@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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
+ * COPYRIGHT OWNER OR CONTRIBUTORS 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 "linker.h"
+#include "linker_debug.h"
+#include "ba.h"
+
+struct ba_bits {
+ unsigned allocated:1; /* 1 if allocated, 0 if free */
+ unsigned order:7; /* size of the region in ba space */
+};
+
+struct ba_info {
+ /* start address of the ba space */
+ unsigned long base;
+ /* total size of the ba space */
+ unsigned long size;
+ /* number of entries in the ba space */
+ int num_entries;
+ /* the bitmap for the region indicating which entries are allocated
+ * and which are free */
+ struct ba_bits *bitmap;
+};
+
+#undef min
+#define min(a,b) ((a)<(b)?(a):(b))
+
+#define BA_MIN_ALLOC LIBINC
+#define BA_MAX_ORDER 128
+#define BA_START LIBBASE
+#define BA_SIZE (LIBLAST - LIBBASE)
+
+#define BA_IS_FREE(index) (!(ba.bitmap[index].allocated))
+#define BA_ORDER(index) ba.bitmap[index].order
+#define BA_BUDDY_INDEX(index) ((index) ^ (1 << BA_ORDER(index)))
+#define BA_NEXT_INDEX(index) ((index) + (1 << BA_ORDER(index)))
+#define BA_OFFSET(index) ((index) * BA_MIN_ALLOC)
+#define BA_START_ADDR(index) (BA_OFFSET(index) + ba.base)
+#define BA_LEN(index) ((1 << BA_ORDER(index)) * BA_MIN_ALLOC)
+
+static struct ba_bits ba_bitmap[BA_SIZE / BA_MIN_ALLOC];
+
+static struct ba_info ba = {
+ .base = BA_START,
+ .size = BA_SIZE,
+ .bitmap = ba_bitmap,
+ .num_entries = sizeof(ba_bitmap)/sizeof(ba_bitmap[0]),
+};
+
+void ba_init(void)
+{
+ int i, index = 0;
+ for (i = sizeof(ba.num_entries) * 8 - 1; i >= 0; i--) {
+ if (ba.num_entries & 1<<i) {
+ BA_ORDER(index) = i;
+ index = BA_NEXT_INDEX(index);
+ }
+ }
+}
+
+int ba_free(int index)
+{
+ int buddy, curr = index;
+
+ /* clean up the bitmap, merging any buddies */
+ ba.bitmap[curr].allocated = 0;
+ /* find a slots buddy Buddy# = Slot# ^ (1 << order)
+ * if the buddy is also free merge them
+ * repeat until the buddy is not free or end of the bitmap is reached
+ */
+ do {
+ buddy = BA_BUDDY_INDEX(curr);
+ if (BA_IS_FREE(buddy) &&
+ BA_ORDER(buddy) == BA_ORDER(curr)) {
+ BA_ORDER(buddy)++;
+ BA_ORDER(curr)++;
+ curr = min(buddy, curr);
+ } else {
+ break;
+ }
+ } while (curr < ba.num_entries);
+
+ return 0;
+}
+
+static unsigned long ba_order(unsigned long len)
+{
+ unsigned long i;
+
+ len = (len + BA_MIN_ALLOC - 1) / BA_MIN_ALLOC;
+ len--;
+ for (i = 0; i < sizeof(len)*8; i++)
+ if (len >> i == 0)
+ break;
+ return i;
+}
+
+int ba_allocate(unsigned long len)
+{
+ int curr = 0;
+ int end = ba.num_entries;
+ int best_fit = -1;
+ unsigned long order = ba_order(len);
+
+ if (order > BA_MAX_ORDER)
+ return -1;
+
+ /* look through the bitmap:
+ * if you find a free slot of the correct order use it
+ * otherwise, use the best fit (smallest with size > order) slot
+ */
+ while (curr < end) {
+ if (BA_IS_FREE(curr)) {
+ if (BA_ORDER(curr) == (unsigned char)order) {
+ /* set the not free bit and clear others */
+ best_fit = curr;
+ break;
+ }
+ if (BA_ORDER(curr) > (unsigned char)order &&
+ (best_fit < 0 ||
+ BA_ORDER(curr) < BA_ORDER(best_fit)))
+ best_fit = curr;
+ }
+ curr = BA_NEXT_INDEX(curr);
+ }
+
+ /* if best_fit < 0, there are no suitable slots,
+ * return an error
+ */
+ if (best_fit < 0)
+ return -1;
+
+ /* now partition the best fit:
+ * split the slot into 2 buddies of order - 1
+ * repeat until the slot is of the correct order
+ */
+ while (BA_ORDER(best_fit) > (unsigned char)order) {
+ int buddy;
+ BA_ORDER(best_fit) -= 1;
+ buddy = BA_BUDDY_INDEX(best_fit);
+ BA_ORDER(buddy) = BA_ORDER(best_fit);
+ }
+ ba.bitmap[best_fit].allocated = 1;
+ return best_fit;
+}
+
+unsigned long ba_start_addr(int index)
+{
+ return BA_START_ADDR(index);
+}
+
+unsigned long ba_len(int index)
+{
+ return BA_LEN(index);
+}