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-rw-r--r--src/VBox/Devices/PC/ipxe/src/interface/linux/linux_umalloc.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/src/VBox/Devices/PC/ipxe/src/interface/linux/linux_umalloc.c b/src/VBox/Devices/PC/ipxe/src/interface/linux/linux_umalloc.c
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+++ b/src/VBox/Devices/PC/ipxe/src/interface/linux/linux_umalloc.c
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2010 Piotr JaroszyƄski <p.jaroszynski@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+FILE_LICENCE(GPL2_OR_LATER);
+
+#include <valgrind/memcheck.h>
+
+/** @file
+ *
+ * iPXE user memory allocation API for linux
+ *
+ */
+
+#include <assert.h>
+#include <ipxe/umalloc.h>
+
+#include <linux_api.h>
+
+/** Special address returned for empty allocations */
+#define NOWHERE ((void *)-1)
+
+/** Poison to make the metadata more unique */
+#define POISON 0xa5a5a5a5
+#define min(a,b) (((a)<(b))?(a):(b))
+
+/** Metadata stored at the beginning of all allocations */
+struct metadata
+{
+ unsigned poison;
+ size_t size;
+};
+
+#define SIZE_MD (sizeof(struct metadata))
+
+/** Simple realloc which passes most of the work to mmap(), mremap() and munmap() */
+static void * linux_realloc(void *ptr, size_t size)
+{
+ struct metadata md = {0, 0};
+ struct metadata * mdptr = NULL;
+
+ DBG2("linux_realloc(%p, %zd)\n", ptr, size);
+
+ /* Check whether we have a valid pointer */
+ if (ptr != NULL && ptr != NOWHERE) {
+ mdptr = ptr - SIZE_MD;
+ VALGRIND_MAKE_MEM_DEFINED(mdptr, SIZE_MD);
+ md = *mdptr;
+ VALGRIND_MAKE_MEM_NOACCESS(mdptr, SIZE_MD);
+
+ /* Check for poison in the metadata */
+ if (md.poison != POISON) {
+ DBG("linux_realloc bad poison: 0x%x (expected 0x%x)\n", md.poison, POISON);
+ return NULL;
+ }
+ } else {
+ /* Handle NOWHERE as NULL */
+ ptr = NULL;
+ }
+
+ /*
+ * At this point, ptr is either NULL or pointing to a region allocated by us.
+ * In the latter case mdptr is pointing to a valid metadata, otherwise it is NULL.
+ */
+
+ /* Handle deallocation or allocation of size 0 */
+ if (size == 0) {
+ if (mdptr) {
+ if (linux_munmap(mdptr, md.size))
+ DBG("linux_realloc munmap failed: %s\n", linux_strerror(linux_errno));
+ VALGRIND_FREELIKE_BLOCK(ptr, sizeof(*mdptr));
+ }
+ return NOWHERE;
+ }
+
+ if (ptr) {
+ char *vbits = NULL;
+
+ if (RUNNING_ON_VALGRIND > 0)
+ vbits = linux_realloc(NULL, min(size, md.size));
+
+/* prevent an unused variable warning when building w/o valgrind support */
+#ifndef NVALGRIND
+ VALGRIND_GET_VBITS(ptr, vbits, min(size, md.size));
+#endif
+
+ VALGRIND_FREELIKE_BLOCK(ptr, SIZE_MD);
+
+ mdptr = linux_mremap(mdptr, md.size + SIZE_MD, size + SIZE_MD, MREMAP_MAYMOVE);
+ if (mdptr == MAP_FAILED) {
+ DBG("linux_realloc mremap failed: %s\n", linux_strerror(linux_errno));
+ return NULL;
+ }
+ ptr = ((void *)mdptr) + SIZE_MD;
+
+ VALGRIND_MALLOCLIKE_BLOCK(ptr, size, SIZE_MD, 0);
+/* prevent an unused variable warning when building w/o valgrind support */
+#ifndef NVALGRIND
+ VALGRIND_SET_VBITS(ptr, vbits, min(size, md.size));
+#endif
+
+ if (RUNNING_ON_VALGRIND > 0)
+ linux_realloc(vbits, 0);
+ } else {
+ mdptr = linux_mmap(NULL, size + SIZE_MD, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mdptr == MAP_FAILED) {
+ DBG("linux_realloc mmap failed: %s\n", linux_strerror(linux_errno));
+ return NULL;
+ }
+ ptr = ((void *)mdptr) + SIZE_MD;
+ VALGRIND_MALLOCLIKE_BLOCK(ptr, size, SIZE_MD, 0);
+ }
+
+ /* Update the metadata */
+ VALGRIND_MAKE_MEM_DEFINED(mdptr, SIZE_MD);
+ mdptr->poison = POISON;
+ mdptr->size = size;
+ VALGRIND_MAKE_MEM_NOACCESS(mdptr, SIZE_MD);
+ // VALGRIND_MALLOCLIKE_BLOCK ignores redzones currently, make our own
+ VALGRIND_MAKE_MEM_NOACCESS(ptr + size, SIZE_MD);
+
+ return ptr;
+}
+
+/**
+ * Reallocate external memory
+ *
+ * @v old_ptr Memory previously allocated by umalloc(), or UNULL
+ * @v new_size Requested size
+ * @ret new_ptr Allocated memory, or UNULL
+ *
+ * Calling realloc() with a new size of zero is a valid way to free a
+ * memory block.
+ */
+static userptr_t linux_urealloc(userptr_t old_ptr, size_t new_size)
+{
+ return (userptr_t)linux_realloc((void *)old_ptr, new_size);
+}
+
+PROVIDE_UMALLOC(linux, urealloc, linux_urealloc);