xref: /openbmc/linux/fs/xfs/kmem.h (revision de3a9980)
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 #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  */
29 static inline gfp_t
30 kmem_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 
59 extern void *kmem_alloc(size_t, xfs_km_flags_t);
60 extern void *kmem_alloc_io(size_t size, int align_mask, xfs_km_flags_t flags);
61 extern void *kmem_alloc_large(size_t size, xfs_km_flags_t);
62 static inline void  kmem_free(const void *ptr)
63 {
64 	kvfree(ptr);
65 }
66 
67 
68 static inline void *
69 kmem_zalloc(size_t size, xfs_km_flags_t flags)
70 {
71 	return kmem_alloc(size, flags | KM_ZERO);
72 }
73 
74 /*
75  * Zone interfaces
76  */
77 
78 #define kmem_zone	kmem_cache
79 #define kmem_zone_t	struct kmem_cache
80 
81 static inline struct page *
82 kmem_to_page(void *addr)
83 {
84 	if (is_vmalloc_addr(addr))
85 		return vmalloc_to_page(addr);
86 	return virt_to_page(addr);
87 }
88 
89 #endif /* __XFS_SUPPORT_KMEM_H__ */
90