bird/lib/resource.h
Maria Matejka 886dd92eee Slab: head now uses bitmask for used/free nodes info instead of lists
From now, there are no auxiliary pointers stored in the free slab nodes.
This led to strange debugging problems if use-after-free happened in
slab-allocated structures, especially if the structure's first member is
a next pointer.

This also reduces the memory needed by 1 pointer per allocated object.
OTOH, we now rely on pages being aligned to their size's multiple, which
is quite common anyway.
2021-03-25 16:47:48 +01:00

130 lines
3.7 KiB
C

/*
* BIRD Resource Manager
*
* (c) 1998--1999 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_RESOURCE_H_
#define _BIRD_RESOURCE_H_
#include "lib/lists.h"
/* Resource */
typedef struct resource {
node n; /* Inside resource pool */
struct resclass *class; /* Resource class */
} resource;
/* Resource class */
struct resclass {
char *name; /* Resource class name */
unsigned size; /* Standard size of single resource */
void (*free)(resource *); /* Freeing function */
void (*dump)(resource *); /* Dump to debug output */
resource *(*lookup)(resource *, unsigned long); /* Look up address (only for debugging) */
size_t (*memsize)(resource *); /* Return size of memory used by the resource, may be NULL */
};
/* Estimate of system allocator overhead per item, for memory consumtion stats */
#define ALLOC_OVERHEAD 8
/* Generic resource manipulation */
typedef struct pool pool;
void resource_init(void);
pool *rp_new(pool *, const char *); /* Create new pool */
void rfree(void *); /* Free single resource */
void rdump(void *); /* Dump to debug output */
size_t rmemsize(void *res); /* Return size of memory used by the resource */
void rlookup(unsigned long); /* Look up address (only for debugging) */
void rmove(void *, pool *); /* Move to a different pool */
void *ralloc(pool *, struct resclass *);
extern pool root_pool;
/* Normal memory blocks */
void *mb_alloc(pool *, unsigned size);
void *mb_allocz(pool *, unsigned size);
void *mb_realloc(void *m, unsigned size);
void mb_free(void *);
/* Memory pools with linear allocation */
typedef struct linpool linpool;
typedef struct lp_state {
void *current, *large;
byte *ptr;
} lp_state;
linpool *lp_new(pool *, unsigned blk);
void *lp_alloc(linpool *, unsigned size); /* Aligned */
void *lp_allocu(linpool *, unsigned size); /* Unaligned */
void *lp_allocz(linpool *, unsigned size); /* With clear */
void lp_flush(linpool *); /* Free everything, but leave linpool */
void lp_save(linpool *m, lp_state *p); /* Save state */
void lp_restore(linpool *m, lp_state *p); /* Restore state */
extern const int lp_chunk_size;
#define LP_GAS 1024
#define LP_GOOD_SIZE(x) (((x + LP_GAS - 1) & (~(LP_GAS - 1))) - lp_chunk_size)
#define lp_new_default(p) lp_new(p, LP_GOOD_SIZE(LP_GAS*4))
/* Slabs */
typedef struct slab slab;
slab *sl_new(pool *, unsigned size);
void *sl_alloc(slab *);
void *sl_allocz(slab *);
void sl_free(slab *, void *);
/*
* Low-level memory allocation functions, please don't use
* outside resource manager and possibly sysdep code.
*/
void buffer_realloc(void **buf, unsigned *size, unsigned need, unsigned item_size);
/* Allocator of whole pages; for use in slabs and other high-level allocators. */
u64 get_page_size(void);
void *alloc_page(void);
void free_page(void *);
#ifdef HAVE_LIBDMALLOC
/*
* The standard dmalloc macros tend to produce lots of namespace
* conflicts and we use only xmalloc, xrealloc and xfree, so we
* can define the stubs ourselves.
*/
#define DMALLOC_DISABLE
#include <dmalloc.h>
#define xmalloc(size) \
dmalloc_malloc(__FILE__, __LINE__, (size), DMALLOC_FUNC_MALLOC, 0, 1)
#define xrealloc(ptr, size) \
dmalloc_realloc(__FILE__, __LINE__, (ptr), (size), DMALLOC_FUNC_REALLOC, 1)
#define xfree(ptr) \
dmalloc_free(__FILE__, __LINE__, (ptr), DMALLOC_FUNC_FREE)
#else
/*
* Unfortunately, several libraries we might want to link to define
* their own xmalloc and we don't want to interfere with them, hence
* the renaming.
*/
#define xmalloc bird_xmalloc
#define xrealloc bird_xrealloc
void *xmalloc(unsigned);
void *xrealloc(void *, unsigned);
#define xfree(x) free(x)
#endif
#endif