X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/378393581903b274cb7a4d18e0d978071a6b592d..5d5c5d0d5b79ade9a973d55186ffda2638ba2b6e:/osfmk/kern/kalloc.c
diff --git a/osfmk/kern/kalloc.c b/osfmk/kern/kalloc.c
index 57161e0bb..ce4a718dc 100644
--- a/osfmk/kern/kalloc.c
+++ b/osfmk/kern/kalloc.c
@@ -1,23 +1,31 @@
/*
* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the
+ * License may not be used to create, or enable the creation or
+ * redistribution of, unlawful or unlicensed copies of an Apple operating
+ * system, or to circumvent, violate, or enable the circumvention or
+ * violation of, any terms of an Apple operating system software license
+ * agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
@@ -80,10 +88,12 @@ vm_map_t kalloc_map;
vm_size_t kalloc_map_size = 16 * 1024 * 1024;
vm_size_t kalloc_max;
vm_size_t kalloc_max_prerounded;
+vm_size_t kalloc_kernmap_size; /* size of kallocs that can come from kernel map */
unsigned int kalloc_large_inuse;
vm_size_t kalloc_large_total;
vm_size_t kalloc_large_max;
+vm_size_t kalloc_largest_allocated = 0;
/*
* All allocations of size less than kalloc_max are rounded to the
@@ -98,6 +108,8 @@ vm_size_t kalloc_large_max;
* It represents the first power of two for which no zone exists.
* kalloc_max_prerounded is the smallest allocation size, before
* rounding, for which no zone exists.
+ * Also if the allocation size is more than kalloc_kernmap_size
+ * then allocate from kernel map rather than kalloc_map.
*/
int first_k_zone = -1;
@@ -189,6 +201,8 @@ kalloc_init(
else
kalloc_max = PAGE_SIZE;
kalloc_max_prerounded = kalloc_max / 2 + 1;
+ /* size it to be more than 16 times kalloc_max (256k) for allocations from kernel map */
+ kalloc_kernmap_size = (kalloc_max * 16) + 1;
/*
* Allocate a zone for each size we are going to handle.
@@ -215,6 +229,7 @@ kalloc_canblock(
{
register int zindex;
register vm_size_t allocsize;
+ vm_map_t alloc_map = VM_MAP_NULL;
/*
* If size is too large for a zone, then use kmem_alloc.
@@ -229,7 +244,16 @@ kalloc_canblock(
if (!canblock) {
return(0);
}
- if (kmem_alloc(kalloc_map, (vm_offset_t *)&addr, size) != KERN_SUCCESS)
+
+ if (size >= kalloc_kernmap_size) {
+ alloc_map = kernel_map;
+
+ if (size > kalloc_largest_allocated)
+ kalloc_largest_allocated = size;
+ } else
+ alloc_map = kalloc_map;
+
+ if (kmem_alloc(alloc_map, (vm_offset_t *)&addr, size) != KERN_SUCCESS)
addr = 0;
if (addr) {
@@ -281,6 +305,7 @@ krealloc(
register int zindex;
register vm_size_t allocsize;
void *naddr;
+ vm_map_t alloc_map = VM_MAP_NULL;
/* can only be used for increasing allocation size */
@@ -299,11 +324,16 @@ krealloc(
/* if old block was kmem_alloc'd, then use kmem_realloc if necessary */
if (old_size >= kalloc_max_prerounded) {
+ if (old_size >= kalloc_kernmap_size)
+ alloc_map = kernel_map;
+ else
+ alloc_map = kalloc_map;
+
old_size = round_page(old_size);
new_size = round_page(new_size);
if (new_size > old_size) {
- if (KERN_SUCCESS != kmem_realloc(kalloc_map,
+ if (KERN_SUCCESS != kmem_realloc(alloc_map,
(vm_offset_t)*addrp, old_size,
(vm_offset_t *)&naddr, new_size)) {
panic("krealloc: kmem_realloc");
@@ -314,7 +344,7 @@ krealloc(
*addrp = (void *) naddr;
/* kmem_realloc() doesn't free old page range. */
- kmem_free(kalloc_map, (vm_offset_t)*addrp, old_size);
+ kmem_free(alloc_map, (vm_offset_t)*addrp, old_size);
kalloc_large_total += (new_size - old_size);
@@ -344,7 +374,11 @@ krealloc(
simple_unlock(lock);
if (new_size >= kalloc_max_prerounded) {
- if (KERN_SUCCESS != kmem_alloc(kalloc_map,
+ if (new_size >= kalloc_kernmap_size)
+ alloc_map = kernel_map;
+ else
+ alloc_map = kalloc_map;
+ if (KERN_SUCCESS != kmem_alloc(alloc_map,
(vm_offset_t *)&naddr, new_size)) {
panic("krealloc: kmem_alloc");
simple_lock(lock);
@@ -419,11 +453,38 @@ kfree(
{
register int zindex;
register vm_size_t freesize;
+ vm_map_t alloc_map = VM_MAP_NULL;
/* if size was too large for a zone, then use kmem_free */
if (size >= kalloc_max_prerounded) {
- kmem_free(kalloc_map, (vm_offset_t)data, size);
+ if (size >= kalloc_kernmap_size) {
+ alloc_map = kernel_map;
+
+ if (size > kalloc_largest_allocated)
+ /*
+ * work around double FREEs of small MALLOCs
+ * this used to end up being a nop
+ * since the pointer being freed from an
+ * alloc backed by the zalloc world could
+ * never show up in the kalloc_map... however,
+ * the kernel_map is a different issue... since it
+ * was released back into the zalloc pool, a pointer
+ * would have gotten written over the 'size' that
+ * the MALLOC was retaining in the first 4 bytes of
+ * the underlying allocation... that pointer ends up
+ * looking like a really big size on the 2nd FREE and
+ * pushes the kfree into the kernel_map... we
+ * end up removing a ton of virutal space before we panic
+ * this check causes us to ignore the kfree for a size
+ * that must be 'bogus'... note that it might not be due
+ * to the above scenario, but it would still be wrong and
+ * cause serious damage.
+ */
+ return;
+ } else
+ alloc_map = kalloc_map;
+ kmem_free(alloc_map, (vm_offset_t)data, size);
kalloc_large_total -= size;
kalloc_large_inuse--;