Revert "Revert "linker: get rid of the buddy allocator""
This reverts commit f9a9cda23a6afc1c2dfdfd624cde23b61941eb5e.
This revert is promised once b/5039224, b/5036755, b/5036610 are resolved.
diff --git a/linker/Android.mk b/linker/Android.mk
index abe5995..60f291c 100644
--- a/linker/Android.mk
+++ b/linker/Android.mk
@@ -8,8 +8,7 @@
linker_format.c \
rt.c \
dlfcn.c \
- debugger.c \
- ba.c
+ debugger.c
ifeq ($(TARGET_ARCH),sh)
# SH-4A series virtual address range from 0x00000000 to 0x7FFFFFFF.
diff --git a/linker/ba.c b/linker/ba.c
deleted file mode 100644
index db49c4b..0000000
--- a/linker/ba.c
+++ /dev/null
@@ -1,156 +0,0 @@
-/*
- * 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"
-
-#undef min
-#define min(a,b) ((a)<(b)?(a):(b))
-
-#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 unsigned long ba_order(struct ba *ba, unsigned long len);
-
-void ba_init(struct ba *ba)
-{
- int i, index = 0;
-
- unsigned long max_order = ba_order(ba, ba->size);
- if (ba->max_order == 0 || ba->max_order > max_order)
- ba->max_order = max_order;
-
- 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(struct ba *ba, 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(struct ba *ba, 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(struct ba *ba, unsigned long len)
-{
- int curr = 0;
- int end = ba->num_entries;
- int best_fit = -1;
- unsigned long order = ba_order(ba, 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(struct ba *ba, int index)
-{
- return BA_START_ADDR(index);
-}
-
-unsigned long ba_len(struct ba *ba, int index)
-{
- return BA_LEN(index);
-}
diff --git a/linker/ba.h b/linker/ba.h
deleted file mode 100644
index c11017b..0000000
--- a/linker/ba.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * 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.
- */
-
-#ifndef __LINKER_BA_H
-#define __LINKER_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 {
- /* start address of the ba space */
- unsigned long base;
- /* total size of the ba space */
- unsigned long size;
- /* the smaller allocation that can be made */
- unsigned long min_alloc;
- /* the order of the largest allocation that can be made */
- unsigned long max_order;
- /* 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;
-};
-
-extern void ba_init(struct ba *ba);
-extern int ba_allocate(struct ba *ba, unsigned long len);
-extern int ba_free(struct ba *ba, int index);
-extern unsigned long ba_start_addr(struct ba *ba, int index);
-extern unsigned long ba_len(struct ba *ba, int index);
-
-#endif
diff --git a/linker/linker.c b/linker/linker.c
index e350d89..4d85064 100644
--- a/linker/linker.c
+++ b/linker/linker.c
@@ -51,8 +51,6 @@
#include "linker_environ.h"
#include "linker_format.h"
-#include "ba.h"
-
#define ALLOW_SYMBOLS_FROM_MAIN 1
#define SO_MAX 128
@@ -96,17 +94,6 @@
#endif
-/* Set up for the buddy allocator managing the non-prelinked libraries. */
-static struct ba_bits ba_nonprelink_bitmap[(LIBLAST - LIBBASE) / LIBINC];
-static struct ba ba_nonprelink = {
- .base = LIBBASE,
- .size = LIBLAST - LIBBASE,
- .min_alloc = LIBINC,
- /* max_order will be determined automatically */
- .bitmap = ba_nonprelink_bitmap,
- .num_entries = sizeof(ba_nonprelink_bitmap)/sizeof(ba_nonprelink_bitmap[0]),
-};
-
static inline int validate_soinfo(soinfo *si)
{
return (si >= sopool && si < sopool + SO_MAX) ||
@@ -292,7 +279,6 @@
memset(si, 0, sizeof(soinfo));
strlcpy((char*) si->name, name, sizeof(si->name));
sonext->next = si;
- si->ba_index = -1; /* by default, prelinked */
si->next = NULL;
si->refcount = 0;
sonext = si;
@@ -844,28 +830,25 @@
{
if (si->base) {
/* Attempt to mmap a prelinked library. */
- si->ba_index = -1;
return reserve_mem_region(si);
}
- /* This is not a prelinked library, so we attempt to allocate space
- for it from the buddy allocator, which manages the area between
- LIBBASE and LIBLAST.
+ /* This is not a prelinked library, so we use the kernel's default
+ allocator.
*/
- si->ba_index = ba_allocate(&ba_nonprelink, si->size);
- if(si->ba_index >= 0) {
- si->base = ba_start_addr(&ba_nonprelink, si->ba_index);
- PRINT("%5d mapping library '%s' at %08x (index %d) " \
- "through buddy allocator.\n",
- pid, si->name, si->base, si->ba_index);
- if (reserve_mem_region(si) < 0) {
- ba_free(&ba_nonprelink, si->ba_index);
- si->ba_index = -1;
- si->base = 0;
- goto err;
- }
- return 0;
+
+ void *base = mmap(NULL, si->size, PROT_READ | PROT_EXEC,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (base == MAP_FAILED) {
+ DL_ERR("%5d mmap of library '%s' failed: %d (%s)\n",
+ pid, si->name,
+ errno, strerror(errno));
+ goto err;
}
+ si->base = (unsigned) base;
+ PRINT("%5d mapped library '%s' to %08x via kernel allocator.\n",
+ pid, si->name, si->base);
+ return 0;
err:
DL_ERR("OOPS: %5d cannot map library '%s'. no vspace available.",
@@ -1154,10 +1137,6 @@
/* Now actually load the library's segments into right places in memory */
if (load_segments(fd, &__header[0], si) < 0) {
- if (si->ba_index >= 0) {
- ba_free(&ba_nonprelink, si->ba_index);
- si->ba_index = -1;
- }
goto fail;
}
@@ -1187,9 +1166,6 @@
TRACE("[ %5d init_library base=0x%08x sz=0x%08x name='%s') ]\n",
pid, si->base, si->size, si->name);
- if (si->base < LIBBASE || si->base >= LIBLAST)
- si->flags |= FLAG_PRELINKED;
-
if(link_image(si, wr_offset)) {
/* We failed to link. However, we can only restore libbase
** if no additional libraries have moved it since we updated it.
@@ -1264,12 +1240,6 @@
}
munmap((char *)si->base, si->size);
- if (si->ba_index >= 0) {
- PRINT("%5d releasing library '%s' address space at %08x "\
- "through buddy allocator.\n",
- pid, si->name, si->base);
- ba_free(&ba_nonprelink, si->ba_index);
- }
notify_gdb_of_unload(si);
free_info(si);
si->refcount = 0;
@@ -2213,8 +2183,6 @@
vecs += 2;
}
- ba_init(&ba_nonprelink);
-
si->base = 0;
si->dynamic = (unsigned *)-1;
si->wrprotect_start = 0xffffffff;
diff --git a/linker/linker.h b/linker/linker.h
index 68ac275..301d268 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -83,7 +83,6 @@
#define FLAG_LINKED 0x00000001
#define FLAG_ERROR 0x00000002
#define FLAG_EXE 0x00000004 // The main executable
-#define FLAG_PRELINKED 0x00000008 // This is a pre-linked lib
#define SOINFO_NAME_LEN 128
@@ -95,8 +94,6 @@
unsigned entry;
unsigned base;
unsigned size;
- // buddy-allocator index, negative for prelinked libraries
- int ba_index;
unsigned *dynamic;
@@ -154,17 +151,6 @@
extern soinfo libdl_info;
-/* these must all be powers of two */
-#ifdef ARCH_SH
-#define LIBBASE 0x60000000
-#define LIBLAST 0x70000000
-#define LIBINC 0x00100000
-#else
-#define LIBBASE 0x80000000
-#define LIBLAST 0x90000000
-#define LIBINC 0x00100000
-#endif
-
#ifdef ANDROID_ARM_LINKER
#define R_ARM_COPY 20