aha/fs/xfs/linux-2.6/kmem.h
Felix Blyakher 1b17d76646 xfs: prevent deadlock in xfs_qm_shake()
It's possible to recurse into filesystem from the memory
allocation, which deadlocks in xfs_qm_shake(). Add check
for __GFP_FS, and bail out if it is not set.

Signed-off-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Hedi Berriche <hedi@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-06-01 22:59:45 -05:00

109 lines
2.9 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>
/*
* General memory allocation interfaces
*/
#define KM_SLEEP 0x0001u
#define KM_NOSLEEP 0x0002u
#define KM_NOFS 0x0004u
#define KM_MAYFAIL 0x0008u
#define KM_LARGE 0x0010u
/*
* 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|KM_LARGE));
if (flags & KM_NOSLEEP) {
lflags = GFP_ATOMIC | __GFP_NOWARN;
} else {
lflags = GFP_KERNEL | __GFP_NOWARN;
if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS))
lflags &= ~__GFP_FS;
}
return lflags;
}
extern void *kmem_alloc(size_t, unsigned int __nocast);
extern void *kmem_zalloc(size_t, unsigned int __nocast);
extern void *kmem_zalloc_greedy(size_t *, size_t, size_t, unsigned int __nocast);
extern void *kmem_realloc(const void *, size_t, size_t, unsigned int __nocast);
extern void kmem_free(const void *);
/*
* Zone interfaces
*/
#define KM_ZONE_HWALIGN SLAB_HWCACHE_ALIGN
#define KM_ZONE_RECLAIM SLAB_RECLAIM_ACCOUNT
#define KM_ZONE_SPREAD SLAB_MEM_SPREAD
#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);
}
static inline kmem_zone_t *
kmem_zone_init_flags(int size, char *zone_name, unsigned long flags,
void (*construct)(void *))
{
return kmem_cache_create(zone_name, size, 0, flags, construct);
}
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);
}
extern void *kmem_zone_alloc(kmem_zone_t *, unsigned int __nocast);
extern void *kmem_zone_zalloc(kmem_zone_t *, unsigned int __nocast);
static inline int
kmem_shake_allow(gfp_t gfp_mask)
{
return ((gfp_mask & __GFP_WAIT) && (gfp_mask & __GFP_FS));
}
#endif /* __XFS_SUPPORT_KMEM_H__ */