include/os/linux/spl/sys/kmem.h

   1 /*
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *
  10  *  The SPL is free software; you can redistribute it and/or modify it
  11  *  under the terms of the GNU General Public License as published by the
  12  *  Free Software Foundation; either version 2 of the License, or (at your
  13  *  option) any later version.
  14  *
  15  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  16  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18  *  for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #ifndef _SPL_KMEM_H
  25 #define _SPL_KMEM_H
  26
  27 #include <sys/debug.h>
  28 #include <linux/slab.h>
  29 #include <linux/sched.h>
  30 #include <linux/mm.h>
  31 #include <linux/vmalloc.h>
  32
  33 extern int kmem_debugging(void);
  34 __attribute__((format(printf, 1, 0)))
  35 extern char *kmem_vasprintf(const char *fmt, va_list ap);
  36 __attribute__((format(printf, 1, 2)))
  37 extern char *kmem_asprintf(const char *fmt, ...);
  38 extern char *kmem_strdup(const char *str);
  39 extern void kmem_strfree(char *str);
  40
  41 #define kmem_scnprintf  scnprintf
  42
  43 #define POINTER_IS_VALID(p)     (!((uintptr_t)(p) & 0x3))
  44 #define POINTER_INVALIDATE(pp)  (*(pp) = (void *)((uintptr_t)(*(pp)) | 0x1))
  45
  46 /*
  47  * Memory allocation interfaces
  48  */
  49 #define KM_SLEEP        0x0000  /* can block for memory; success guaranteed */
  50 #define KM_NOSLEEP      0x0001  /* cannot block for memory; may fail */
  51 #define KM_PUSHPAGE     0x0004  /* can block for memory; may use reserve */
  52 #define KM_ZERO         0x1000  /* zero the allocation */
  53 #define KM_VMEM         0x2000  /* caller is vmem_* wrapper */
  54
  55 #define KM_PUBLIC_MASK  (KM_SLEEP | KM_NOSLEEP | KM_PUSHPAGE)
  56
  57 static int spl_fstrans_check(void);
  58 void *spl_kvmalloc(size_t size, gfp_t flags);
  59
  60 /*
  61  * Convert a KM_* flags mask to its Linux GFP_* counterpart.  The conversion
  62  * function is context aware which means that KM_SLEEP allocations can be
  63  * safely used in syncing contexts which have set PF_FSTRANS.
  64  */
  65 static inline gfp_t
  66 kmem_flags_convert(int flags)
  67 {
  68         gfp_t lflags = __GFP_NOWARN | __GFP_COMP;
  69
  70         if (flags & KM_NOSLEEP) {
  71                 lflags |= GFP_ATOMIC | __GFP_NORETRY;
  72         } else {
  73                 lflags |= GFP_KERNEL;
  74                 if (spl_fstrans_check())
  75                         lflags &= ~(__GFP_IO|__GFP_FS);
  76         }
  77
  78         if (flags & KM_PUSHPAGE)
  79                 lflags |= __GFP_HIGH;
  80
  81         if (flags & KM_ZERO)
  82                 lflags |= __GFP_ZERO;
  83
  84         return (lflags);
  85 }
  86
  87 typedef struct {
  88         struct task_struct *fstrans_thread;
  89         unsigned int saved_flags;
  90 } fstrans_cookie_t;
  91
  92 /*
  93  * Introduced in Linux 3.9, however this cannot be solely relied on before
  94  * Linux 3.18 as it doesn't turn off __GFP_FS as it should.
  95  */
  96 #ifdef PF_MEMALLOC_NOIO
  97 #define __SPL_PF_MEMALLOC_NOIO (PF_MEMALLOC_NOIO)
  98 #else
  99 #define __SPL_PF_MEMALLOC_NOIO (0)
 100 #endif
 101
 102 /*
 103  * PF_FSTRANS is removed from Linux 4.12
 104  */
 105 #ifdef PF_FSTRANS
 106 #define __SPL_PF_FSTRANS (PF_FSTRANS)
 107 #else
 108 #define __SPL_PF_FSTRANS (0)
 109 #endif
 110
 111 #define SPL_FSTRANS (__SPL_PF_FSTRANS|__SPL_PF_MEMALLOC_NOIO)
 112
 113 static inline fstrans_cookie_t
 114 spl_fstrans_mark(void)
 115 {
 116         fstrans_cookie_t cookie;
 117
 118         BUILD_BUG_ON(SPL_FSTRANS == 0);
 119
 120         cookie.fstrans_thread = current;
 121         cookie.saved_flags = current->flags & SPL_FSTRANS;
 122         current->flags |= SPL_FSTRANS;
 123
 124         return (cookie);
 125 }
 126
 127 static inline void
 128 spl_fstrans_unmark(fstrans_cookie_t cookie)
 129 {
 130         ASSERT3P(cookie.fstrans_thread, ==, current);
 131         ASSERT((current->flags & SPL_FSTRANS) == SPL_FSTRANS);
 132
 133         current->flags &= ~SPL_FSTRANS;
 134         current->flags |= cookie.saved_flags;
 135 }
 136
 137 static inline int
 138 spl_fstrans_check(void)
 139 {
 140         return (current->flags & SPL_FSTRANS);
 141 }
 142
 143 /*
 144  * specifically used to check PF_FSTRANS flag, cannot be relied on for
 145  * checking spl_fstrans_mark().
 146  */
 147 static inline int
 148 __spl_pf_fstrans_check(void)
 149 {
 150         return (current->flags & __SPL_PF_FSTRANS);
 151 }
 152
 153 /*
 154  * Kernel compatibility for GFP flags
 155  */
 156 /* < 4.13 */
 157 #ifndef __GFP_RETRY_MAYFAIL
 158 #define __GFP_RETRY_MAYFAIL     __GFP_REPEAT
 159 #endif
 160 /* < 4.4 */
 161 #ifndef __GFP_RECLAIM
 162 #define __GFP_RECLAIM           __GFP_WAIT
 163 #endif
 164
 165 #ifdef HAVE_ATOMIC64_T
 166 #define kmem_alloc_used_add(size)       atomic64_add(size, &kmem_alloc_used)
 167 #define kmem_alloc_used_sub(size)       atomic64_sub(size, &kmem_alloc_used)
 168 #define kmem_alloc_used_read()          atomic64_read(&kmem_alloc_used)
 169 #define kmem_alloc_used_set(size)       atomic64_set(&kmem_alloc_used, size)
 170 extern atomic64_t kmem_alloc_used;
 171 extern unsigned long long kmem_alloc_max;
 172 #else  /* HAVE_ATOMIC64_T */
 173 #define kmem_alloc_used_add(size)       atomic_add(size, &kmem_alloc_used)
 174 #define kmem_alloc_used_sub(size)       atomic_sub(size, &kmem_alloc_used)
 175 #define kmem_alloc_used_read()          atomic_read(&kmem_alloc_used)
 176 #define kmem_alloc_used_set(size)       atomic_set(&kmem_alloc_used, size)
 177 extern atomic_t kmem_alloc_used;
 178 extern unsigned long long kmem_alloc_max;
 179 #endif /* HAVE_ATOMIC64_T */
 180
 181 extern unsigned int spl_kmem_alloc_warn;
 182 extern unsigned int spl_kmem_alloc_max;
 183
 184 #define kmem_alloc(sz, fl)      spl_kmem_alloc((sz), (fl), __func__, __LINE__)
 185 #define kmem_zalloc(sz, fl)     spl_kmem_zalloc((sz), (fl), __func__, __LINE__)
 186 #define kmem_free(ptr, sz)      spl_kmem_free((ptr), (sz))
 187 #define kmem_cache_reap_active  spl_kmem_cache_reap_active
 188
 189 __attribute__((malloc, alloc_size(1)))
 190 extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
 191 __attribute__((malloc, alloc_size(1)))
 192 extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
 193 extern void spl_kmem_free(const void *ptr, size_t sz);
 194
 195 /*
 196  * 5.8 API change, pgprot_t argument removed.
 197  */
 198 #ifdef HAVE_VMALLOC_PAGE_KERNEL
 199 #define spl_vmalloc(size, flags)        __vmalloc(size, flags, PAGE_KERNEL)
 200 #else
 201 #define spl_vmalloc(size, flags)        __vmalloc(size, flags)
 202 #endif
 203
 204 /*
 205  * The following functions are only available for internal use.
 206  */
 207 extern void *spl_kmem_alloc_impl(size_t size, int flags, int node);
 208 extern void *spl_kmem_alloc_debug(size_t size, int flags, int node);
 209 extern void *spl_kmem_alloc_track(size_t size, int flags,
 210     const char *func, int line, int node);
 211 extern void spl_kmem_free_impl(const void *buf, size_t size);
 212 extern void spl_kmem_free_debug(const void *buf, size_t size);
 213 extern void spl_kmem_free_track(const void *buf, size_t size);
 214
 215 extern int spl_kmem_init(void);
 216 extern void spl_kmem_fini(void);
 217 extern int spl_kmem_cache_reap_active(void);
 218
 219 #endif  /* _SPL_KMEM_H */