xref: /freebsd/sys/contrib/openzfs/include/os/linux/spl/sys/kmem.h (revision 61145dc2b94f12f6a47344fb9aac702321880e43)
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 PF_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  * Introduced in Linux 3.9, however this cannot be solely relied on before
95  * Linux 3.18 as it doesn't turn off __GFP_FS as it should.
96  */
97 #ifdef PF_MEMALLOC_NOIO
98 #define	__SPL_PF_MEMALLOC_NOIO (PF_MEMALLOC_NOIO)
99 #else
100 #define	__SPL_PF_MEMALLOC_NOIO (0)
101 #endif
102 
103 /*
104  * PF_FSTRANS is removed from Linux 4.12
105  */
106 #ifdef PF_FSTRANS
107 #define	__SPL_PF_FSTRANS (PF_FSTRANS)
108 #else
109 #define	__SPL_PF_FSTRANS (0)
110 #endif
111 
112 #define	SPL_FSTRANS (__SPL_PF_FSTRANS|__SPL_PF_MEMALLOC_NOIO)
113 
114 static inline fstrans_cookie_t
spl_fstrans_mark(void)115 spl_fstrans_mark(void)
116 {
117 	fstrans_cookie_t cookie;
118 
119 	BUILD_BUG_ON(SPL_FSTRANS == 0);
120 
121 	cookie.fstrans_thread = current;
122 	cookie.saved_flags = current->flags & SPL_FSTRANS;
123 	current->flags |= SPL_FSTRANS;
124 
125 	return (cookie);
126 }
127 
128 static inline void
spl_fstrans_unmark(fstrans_cookie_t cookie)129 spl_fstrans_unmark(fstrans_cookie_t cookie)
130 {
131 	ASSERT3P(cookie.fstrans_thread, ==, current);
132 	ASSERT((current->flags & SPL_FSTRANS) == SPL_FSTRANS);
133 
134 	current->flags &= ~SPL_FSTRANS;
135 	current->flags |= cookie.saved_flags;
136 }
137 
138 static inline int
spl_fstrans_check(void)139 spl_fstrans_check(void)
140 {
141 	return (current->flags & SPL_FSTRANS);
142 }
143 
144 /*
145  * specifically used to check PF_FSTRANS flag, cannot be relied on for
146  * checking spl_fstrans_mark().
147  */
148 static inline int
__spl_pf_fstrans_check(void)149 __spl_pf_fstrans_check(void)
150 {
151 	return (current->flags & __SPL_PF_FSTRANS);
152 }
153 
154 /*
155  * Kernel compatibility for GFP flags
156  */
157 /* < 4.13 */
158 #ifndef __GFP_RETRY_MAYFAIL
159 #define	__GFP_RETRY_MAYFAIL	__GFP_REPEAT
160 #endif
161 /* < 4.4 */
162 #ifndef __GFP_RECLAIM
163 #define	__GFP_RECLAIM		__GFP_WAIT
164 #endif
165 
166 #ifdef HAVE_ATOMIC64_T
167 #define	kmem_alloc_used_add(size)	atomic64_add(size, &kmem_alloc_used)
168 #define	kmem_alloc_used_sub(size)	atomic64_sub(size, &kmem_alloc_used)
169 #define	kmem_alloc_used_read()		atomic64_read(&kmem_alloc_used)
170 #define	kmem_alloc_used_set(size)	atomic64_set(&kmem_alloc_used, size)
171 extern atomic64_t kmem_alloc_used;
172 extern unsigned long long kmem_alloc_max;
173 #else  /* HAVE_ATOMIC64_T */
174 #define	kmem_alloc_used_add(size)	atomic_add(size, &kmem_alloc_used)
175 #define	kmem_alloc_used_sub(size)	atomic_sub(size, &kmem_alloc_used)
176 #define	kmem_alloc_used_read()		atomic_read(&kmem_alloc_used)
177 #define	kmem_alloc_used_set(size)	atomic_set(&kmem_alloc_used, size)
178 extern atomic_t kmem_alloc_used;
179 extern unsigned long long kmem_alloc_max;
180 #endif /* HAVE_ATOMIC64_T */
181 
182 extern unsigned int spl_kmem_alloc_warn;
183 extern unsigned int spl_kmem_alloc_max;
184 
185 #define	kmem_alloc(sz, fl)	spl_kmem_alloc((sz), (fl), __func__, __LINE__)
186 #define	kmem_zalloc(sz, fl)	spl_kmem_zalloc((sz), (fl), __func__, __LINE__)
187 #define	kmem_free(ptr, sz)	spl_kmem_free((ptr), (sz))
188 #define	kmem_cache_reap_active	spl_kmem_cache_reap_active
189 
190 __attribute__((malloc, alloc_size(1)))
191 extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
192 __attribute__((malloc, alloc_size(1)))
193 extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
194 extern void spl_kmem_free(const void *ptr, size_t sz);
195 
196 /*
197  * 5.8 API change, pgprot_t argument removed.
198  */
199 #ifdef HAVE_VMALLOC_PAGE_KERNEL
200 #define	spl_vmalloc(size, flags)	__vmalloc(size, flags, PAGE_KERNEL)
201 #else
202 #define	spl_vmalloc(size, flags)	__vmalloc(size, flags)
203 #endif
204 
205 /*
206  * The following functions are only available for internal use.
207  */
208 extern void *spl_kmem_alloc_impl(size_t size, int flags, int node);
209 extern void *spl_kmem_alloc_debug(size_t size, int flags, int node);
210 extern void *spl_kmem_alloc_track(size_t size, int flags,
211     const char *func, int line, int node);
212 extern void spl_kmem_free_impl(const void *buf, size_t size);
213 extern void spl_kmem_free_debug(const void *buf, size_t size);
214 extern void spl_kmem_free_track(const void *buf, size_t size);
215 
216 extern int spl_kmem_init(void);
217 extern void spl_kmem_fini(void);
218 extern int spl_kmem_cache_reap_active(void);
219 
220 #endif	/* _SPL_KMEM_H */
221