xref: /freebsd/sys/contrib/openzfs/include/os/linux/spl/sys/kmem.h (revision df58e8b1506f241670be86a560fb6e8432043aee)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
4  *  Copyright (C) 2007 The Regents of the University of California.
5  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
6  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
7  *  UCRL-CODE-235197
8  *
9  *  This file is part of the SPL, Solaris Porting Layer.
10  *
11  *  The SPL is free software; you can redistribute it and/or modify it
12  *  under the terms of the GNU General Public License as published by the
13  *  Free Software Foundation; either version 2 of the License, or (at your
14  *  option) any later version.
15  *
16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
19  *  for more details.
20  *
21  *  You should have received a copy of the GNU General Public License along
22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
23  */
24 
25 #ifndef _SPL_KMEM_H
26 #define	_SPL_KMEM_H
27 
28 #include <sys/debug.h>
29 #include <linux/slab.h>
30 #include <linux/sched.h>
31 #include <linux/mm.h>
32 #include <linux/vmalloc.h>
33 
34 extern int kmem_debugging(void);
35 __attribute__((format(printf, 1, 0)))
36 extern char *kmem_vasprintf(const char *fmt, va_list ap);
37 __attribute__((format(printf, 1, 2)))
38 extern char *kmem_asprintf(const char *fmt, ...);
39 extern char *kmem_strdup(const char *str);
40 extern void kmem_strfree(char *str);
41 
42 #define	kmem_scnprintf	scnprintf
43 
44 #define	POINTER_IS_VALID(p)	(!((uintptr_t)(p) & 0x3))
45 #define	POINTER_INVALIDATE(pp)	(*(pp) = (void *)((uintptr_t)(*(pp)) | 0x1))
46 
47 /*
48  * Memory allocation interfaces
49  */
50 #define	KM_SLEEP	0x0000	/* can block for memory; success guaranteed */
51 #define	KM_NOSLEEP	0x0001	/* cannot block for memory; may fail */
52 #define	KM_PUSHPAGE	0x0004	/* can block for memory; may use reserve */
53 #define	KM_ZERO		0x1000	/* zero the allocation */
54 #define	KM_VMEM		0x2000	/* caller is vmem_* wrapper */
55 
56 #define	KM_PUBLIC_MASK	(KM_SLEEP | KM_NOSLEEP | KM_PUSHPAGE)
57 
58 static int spl_fstrans_check(void);
59 void *spl_kvmalloc(size_t size, gfp_t flags);
60 
61 /*
62  * Convert a KM_* flags mask to its Linux GFP_* counterpart.  The conversion
63  * function is context aware which means that KM_SLEEP allocations can be
64  * safely used in syncing contexts which have set SPL_FSTRANS.
65  */
66 static inline gfp_t
kmem_flags_convert(int flags)67 kmem_flags_convert(int flags)
68 {
69 	gfp_t lflags = __GFP_NOWARN | __GFP_COMP;
70 
71 	if (flags & KM_NOSLEEP) {
72 		lflags |= GFP_ATOMIC | __GFP_NORETRY;
73 	} else {
74 		lflags |= GFP_KERNEL;
75 		if (spl_fstrans_check())
76 			lflags &= ~(__GFP_IO|__GFP_FS);
77 	}
78 
79 	if (flags & KM_PUSHPAGE)
80 		lflags |= __GFP_HIGH;
81 
82 	if (flags & KM_ZERO)
83 		lflags |= __GFP_ZERO;
84 
85 	return (lflags);
86 }
87 
88 typedef struct {
89 	struct task_struct *fstrans_thread;
90 	unsigned int saved_flags;
91 } fstrans_cookie_t;
92 
93 /*
94  * SPL_FSTRANS is the set of flags that indicate that the task is in a
95  * filesystem or IO codepath, and so any allocation must not call back into
96  * those codepaths (eg to swap).
97  */
98 #define	SPL_FSTRANS (PF_MEMALLOC_NOIO)
99 
100 static inline fstrans_cookie_t
spl_fstrans_mark(void)101 spl_fstrans_mark(void)
102 {
103 	fstrans_cookie_t cookie;
104 
105 	BUILD_BUG_ON(SPL_FSTRANS == 0);
106 
107 	cookie.fstrans_thread = current;
108 	cookie.saved_flags = current->flags & SPL_FSTRANS;
109 	current->flags |= SPL_FSTRANS;
110 
111 	return (cookie);
112 }
113 
114 static inline void
spl_fstrans_unmark(fstrans_cookie_t cookie)115 spl_fstrans_unmark(fstrans_cookie_t cookie)
116 {
117 	ASSERT3P(cookie.fstrans_thread, ==, current);
118 	ASSERT((current->flags & SPL_FSTRANS) == SPL_FSTRANS);
119 
120 	current->flags &= ~SPL_FSTRANS;
121 	current->flags |= cookie.saved_flags;
122 }
123 
124 static inline int
spl_fstrans_check(void)125 spl_fstrans_check(void)
126 {
127 	return (current->flags & SPL_FSTRANS);
128 }
129 
130 extern atomic64_t kmem_alloc_used;
131 extern uint64_t kmem_alloc_max;
132 
133 extern unsigned int spl_kmem_alloc_warn;
134 extern unsigned int spl_kmem_alloc_max;
135 
136 #define	kmem_alloc(sz, fl)	spl_kmem_alloc((sz), (fl), __func__, __LINE__)
137 #define	kmem_zalloc(sz, fl)	spl_kmem_zalloc((sz), (fl), __func__, __LINE__)
138 #define	kmem_free(ptr, sz)	spl_kmem_free((ptr), (sz))
139 #define	kmem_cache_reap_active	spl_kmem_cache_reap_active
140 
141 __attribute__((malloc, alloc_size(1)))
142 extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
143 __attribute__((malloc, alloc_size(1)))
144 extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
145 extern void spl_kmem_free(const void *ptr, size_t sz);
146 
147 /*
148  * 5.8 API change, pgprot_t argument removed.
149  */
150 #ifdef HAVE_VMALLOC_PAGE_KERNEL
151 #define	spl_vmalloc(size, flags)	__vmalloc(size, flags, PAGE_KERNEL)
152 #else
153 #define	spl_vmalloc(size, flags)	__vmalloc(size, flags)
154 #endif
155 
156 /*
157  * The following functions are only available for internal use.
158  */
159 extern void *spl_kmem_alloc_impl(size_t size, int flags, int node);
160 extern void *spl_kmem_alloc_debug(size_t size, int flags, int node);
161 extern void *spl_kmem_alloc_track(size_t size, int flags,
162     const char *func, int line, int node);
163 extern void spl_kmem_free_impl(const void *buf, size_t size);
164 extern void spl_kmem_free_debug(const void *buf, size_t size);
165 extern void spl_kmem_free_track(const void *buf, size_t size);
166 
167 extern int spl_kmem_init(void);
168 extern void spl_kmem_fini(void);
169 extern int spl_kmem_cache_reap_active(void);
170 
171 #endif	/* _SPL_KMEM_H */
172