xref: /kernel/linux/linux-6.6/fs/xfs/kmem.h (revision 62306a36) 
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#ifndef __XFS_SUPPORT_KMEM_H__
7#define __XFS_SUPPORT_KMEM_H__
8
9#include <linux/slab.h>
10#include <linux/sched.h>
11#include <linux/mm.h>
12#include <linux/vmalloc.h>
13
14/*
15 * General memory allocation interfaces
16 */
17
18typedef unsigned __bitwise xfs_km_flags_t;
19#define KM_NOFS		((__force xfs_km_flags_t)0x0004u)
20#define KM_MAYFAIL	((__force xfs_km_flags_t)0x0008u)
21#define KM_ZERO		((__force xfs_km_flags_t)0x0010u)
22#define KM_NOLOCKDEP	((__force xfs_km_flags_t)0x0020u)
23
24/*
25 * We use a special process flag to avoid recursive callbacks into
26 * the filesystem during transactions.  We will also issue our own
27 * warnings, so we explicitly skip any generic ones (silly of us).
28 */
29static inline gfp_t
30kmem_flags_convert(xfs_km_flags_t flags)
31{
32	gfp_t	lflags;
33
34	BUG_ON(flags & ~(KM_NOFS | KM_MAYFAIL | KM_ZERO | KM_NOLOCKDEP));
35
36	lflags = GFP_KERNEL | __GFP_NOWARN;
37	if (flags & KM_NOFS)
38		lflags &= ~__GFP_FS;
39
40	/*
41	 * Default page/slab allocator behavior is to retry for ever
42	 * for small allocations. We can override this behavior by using
43	 * __GFP_RETRY_MAYFAIL which will tell the allocator to retry as long
44	 * as it is feasible but rather fail than retry forever for all
45	 * request sizes.
46	 */
47	if (flags & KM_MAYFAIL)
48		lflags |= __GFP_RETRY_MAYFAIL;
49
50	if (flags & KM_ZERO)
51		lflags |= __GFP_ZERO;
52
53	if (flags & KM_NOLOCKDEP)
54		lflags |= __GFP_NOLOCKDEP;
55
56	return lflags;
57}
58
59extern void *kmem_alloc(size_t, xfs_km_flags_t);
60static inline void  kmem_free(const void *ptr)
61{
62	kvfree(ptr);
63}
64
65
66static inline void *
67kmem_zalloc(size_t size, xfs_km_flags_t flags)
68{
69	return kmem_alloc(size, flags | KM_ZERO);
70}
71
72/*
73 * Zone interfaces
74 */
75static inline struct page *
76kmem_to_page(void *addr)
77{
78	if (is_vmalloc_addr(addr))
79		return vmalloc_to_page(addr);
80	return virt_to_page(addr);
81}
82
83#endif /* __XFS_SUPPORT_KMEM_H__ */
84