Aren/haiku
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

added a magic value to check clobbering of the free list

Browse Source 
git-svn-id: file:///srv/svn/repos/haiku/trunk/current@2103 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
beveloper 2002-11-28 14:10:20 +00:00
parent 60d9ed9e3b
commit 3b70f94330
2 changed files with 20 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
headers/private/kernel/pools.h
View File

@ -1,4 +1,4 @@
/* pools.h
/* pools.h
* simple fixed size block allocator
*/
@ -21,8 +21,12 @@ struct pool_mem {
benaphore lock;
};
#define FREE_MAGIC 'BORK'
struct free_blk {
char *next;
uint32 magic;
struct free_blk *next;
uint32 magic_check;
};
#define POOL_USES_BENAPHORES 0
@ -30,7 +34,7 @@ struct free_blk {
struct pool_ctl {
struct pool_mem *list;
char *freelist;
struct free_blk *freelist;
size_t alloc_size;
size_t block_size;
#if POOL_USES_BENAPHORES

22
src/kernel/core/pools.c
View File

@ -35,7 +35,7 @@ void walk_pool_list(struct pool_ctl *p)
void pool_debug_walk(struct pool_ctl *p)
{
char *ptr;
struct free_blk *ptr;
int i = 1;
dprintf("%ld byte blocks allocated, but now free:\n\n", p->alloc_size);
@ -47,8 +47,10 @@ void pool_debug_walk(struct pool_ctl *p)
#endif
ptr = p->freelist;
while (ptr) {
ASSERT(ptr->magic == FREE_MAGIC);
ASSERT(FREE_MAGIC + (uint32)ptr->next == ptr->magic_check);
dprintf(" %02d: %p\n", i++, ptr);
ptr = ((struct free_blk*)ptr)->next;
ptr = ptr->next;
}
#if POOL_USES_BENAPHORES
RELEASE_BENAPHORE(p->lock);
@ -96,9 +98,7 @@ static struct pool_mem *get_mem_block(struct pool_ctl *pool)
#endif
// insert block at the beginning of the pools
if (pool->list)
block->next = pool->list;
block->next = pool->list;
pool->list = block;
#ifdef WALK_POOL_LIST
@ -187,7 +187,7 @@ char *pool_get(struct pool_ctl *p)
{
/* ok, so now we look for a suitable block... */
struct pool_mem *mp = p->list;
char *rv = NULL;
struct free_blk *rv = NULL;
#if POOL_USES_BENAPHORES
ACQUIRE_BENAPHORE(p->lock);
@ -199,13 +199,14 @@ char *pool_get(struct pool_ctl *p)
/* woohoo, just grab a block! */
rv = p->freelist;
ASSERT(rv->magic == FREE_MAGIC);
ASSERT(FREE_MAGIC + (uint32)rv->next == rv->magic_check);
if (p->debug)
dprintf("%s: allocating %p, setting freelist to %p\n",
p->name, p->freelist,
((struct free_blk*)rv)->next);
p->name, p->freelist, rv->next);
p->freelist = ((struct free_blk*)rv)->next;
p->freelist = rv->next;
#if POOL_USES_BENAPHORES
RELEASE_BENAPHORE(p->lock);
@ -276,7 +277,10 @@ void pool_put(struct pool_ctl *p, void *ptr)
#endif
memset(ptr, 0, p->alloc_size);
((struct free_blk*)ptr)->next = p->freelist;
((struct free_blk*)ptr)->magic = FREE_MAGIC;
((struct free_blk*)ptr)->magic_check = FREE_MAGIC + (uint32)p->freelist;
if (p->debug) {
dprintf("%s: adding %p, setting next = %p\n",