linux/fs/xfs/linux-2.6/kmem.h
Nathan Scott 8758280fcc [XFS] Cleanup the use of zones/slabs, more consistent and allows flags to
be passed.

SGI-PV: 949073
SGI-Modid: xfs-linux-melb:xfs-kern:25122a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-03-14 13:18:19 +11:00

163 lines
4.0 KiB
C

/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* 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.
*
* This program is distributed in the hope that it would 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 the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_SUPPORT_KMEM_H__
#define __XFS_SUPPORT_KMEM_H__
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mm.h>
/*
* Process flags handling
*/
#define PFLAGS_TEST_NOIO() (current->flags & PF_NOIO)
#define PFLAGS_TEST_FSTRANS() (current->flags & PF_FSTRANS)
#define PFLAGS_SET_NOIO() do { \
current->flags |= PF_NOIO; \
} while (0)
#define PFLAGS_CLEAR_NOIO() do { \
current->flags &= ~PF_NOIO; \
} while (0)
/* these could be nested, so we save state */
#define PFLAGS_SET_FSTRANS(STATEP) do { \
*(STATEP) = current->flags; \
current->flags |= PF_FSTRANS; \
} while (0)
#define PFLAGS_CLEAR_FSTRANS(STATEP) do { \
*(STATEP) = current->flags; \
current->flags &= ~PF_FSTRANS; \
} while (0)
/* Restore the PF_FSTRANS state to what was saved in STATEP */
#define PFLAGS_RESTORE_FSTRANS(STATEP) do { \
current->flags = ((current->flags & ~PF_FSTRANS) | \
(*(STATEP) & PF_FSTRANS)); \
} while (0)
#define PFLAGS_DUP(OSTATEP, NSTATEP) do { \
*(NSTATEP) = *(OSTATEP); \
} while (0)
/*
* General memory allocation interfaces
*/
#define KM_SLEEP 0x0001u
#define KM_NOSLEEP 0x0002u
#define KM_NOFS 0x0004u
#define KM_MAYFAIL 0x0008u
/*
* We use a special process flag to avoid recursive callbacks into
* the filesystem during transactions. We will also issue our own
* warnings, so we explicitly skip any generic ones (silly of us).
*/
static inline gfp_t
kmem_flags_convert(unsigned int __nocast flags)
{
gfp_t lflags;
BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL));
if (flags & KM_NOSLEEP) {
lflags = GFP_ATOMIC | __GFP_NOWARN;
} else {
lflags = GFP_KERNEL | __GFP_NOWARN;
if (PFLAGS_TEST_FSTRANS() || (flags & KM_NOFS))
lflags &= ~__GFP_FS;
}
return lflags;
}
extern void *kmem_alloc(size_t, unsigned int __nocast);
extern void *kmem_realloc(void *, size_t, size_t, unsigned int __nocast);
extern void *kmem_zalloc(size_t, unsigned int __nocast);
extern void kmem_free(void *, size_t);
/*
* Zone interfaces
*/
#define KM_ZONE_HWALIGN SLAB_HWCACHE_ALIGN
#define KM_ZONE_RECLAIM SLAB_RECLAIM_ACCOUNT
#define KM_ZONE_SPREAD 0
#define kmem_zone kmem_cache
#define kmem_zone_t struct kmem_cache
static inline kmem_zone_t *
kmem_zone_init(int size, char *zone_name)
{
return kmem_cache_create(zone_name, size, 0, 0, NULL, NULL);
}
static inline kmem_zone_t *
kmem_zone_init_flags(int size, char *zone_name, unsigned long flags,
void (*construct)(void *, kmem_zone_t *, unsigned long))
{
return kmem_cache_create(zone_name, size, 0, flags, construct, NULL);
}
static inline void
kmem_zone_free(kmem_zone_t *zone, void *ptr)
{
kmem_cache_free(zone, ptr);
}
static inline void
kmem_zone_destroy(kmem_zone_t *zone)
{
if (zone && kmem_cache_destroy(zone))
BUG();
}
extern void *kmem_zone_alloc(kmem_zone_t *, unsigned int __nocast);
extern void *kmem_zone_zalloc(kmem_zone_t *, unsigned int __nocast);
/*
* Low memory cache shrinkers
*/
typedef struct shrinker *kmem_shaker_t;
typedef int (*kmem_shake_func_t)(int, gfp_t);
static inline kmem_shaker_t
kmem_shake_register(kmem_shake_func_t sfunc)
{
return set_shrinker(DEFAULT_SEEKS, sfunc);
}
static inline void
kmem_shake_deregister(kmem_shaker_t shrinker)
{
remove_shrinker(shrinker);
}
static inline int
kmem_shake_allow(gfp_t gfp_mask)
{
return (gfp_mask & __GFP_WAIT);
}
#endif /* __XFS_SUPPORT_KMEM_H__ */