xref: /openbmc/linux/fs/xfs/kmem.h (revision 37744fee)
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 
18 typedef 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 
23 /*
24  * We use a special process flag to avoid recursive callbacks into
25  * the filesystem during transactions.  We will also issue our own
26  * warnings, so we explicitly skip any generic ones (silly of us).
27  */
28 static inline gfp_t
29 kmem_flags_convert(xfs_km_flags_t flags)
30 {
31 	gfp_t	lflags;
32 
33 	BUG_ON(flags & ~(KM_NOFS|KM_MAYFAIL|KM_ZERO));
34 
35 	lflags = GFP_KERNEL | __GFP_NOWARN;
36 	if (flags & KM_NOFS)
37 		lflags &= ~__GFP_FS;
38 
39 	/*
40 	 * Default page/slab allocator behavior is to retry for ever
41 	 * for small allocations. We can override this behavior by using
42 	 * __GFP_RETRY_MAYFAIL which will tell the allocator to retry as long
43 	 * as it is feasible but rather fail than retry forever for all
44 	 * request sizes.
45 	 */
46 	if (flags & KM_MAYFAIL)
47 		lflags |= __GFP_RETRY_MAYFAIL;
48 
49 	if (flags & KM_ZERO)
50 		lflags |= __GFP_ZERO;
51 
52 	return lflags;
53 }
54 
55 extern void *kmem_alloc(size_t, xfs_km_flags_t);
56 extern void *kmem_alloc_io(size_t size, int align_mask, xfs_km_flags_t flags);
57 extern void *kmem_alloc_large(size_t size, xfs_km_flags_t);
58 extern void *kmem_realloc(const void *, size_t, xfs_km_flags_t);
59 static inline void  kmem_free(const void *ptr)
60 {
61 	kvfree(ptr);
62 }
63 
64 
65 static inline void *
66 kmem_zalloc(size_t size, xfs_km_flags_t flags)
67 {
68 	return kmem_alloc(size, flags | KM_ZERO);
69 }
70 
71 static inline void *
72 kmem_zalloc_large(size_t size, xfs_km_flags_t flags)
73 {
74 	return kmem_alloc_large(size, flags | KM_ZERO);
75 }
76 
77 /*
78  * Zone interfaces
79  */
80 
81 #define kmem_zone	kmem_cache
82 #define kmem_zone_t	struct kmem_cache
83 
84 extern void *kmem_zone_alloc(kmem_zone_t *, xfs_km_flags_t);
85 
86 static inline void *
87 kmem_zone_zalloc(kmem_zone_t *zone, xfs_km_flags_t flags)
88 {
89 	return kmem_zone_alloc(zone, flags | KM_ZERO);
90 }
91 
92 static inline struct page *
93 kmem_to_page(void *addr)
94 {
95 	if (is_vmalloc_addr(addr))
96 		return vmalloc_to_page(addr);
97 	return virt_to_page(addr);
98 }
99 
100 #endif /* __XFS_SUPPORT_KMEM_H__ */
101