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  *  For details, see <http://zfsonlinux.org/>.
  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 extern char *kmem_vasprintf(const char *fmt, va_list ap);
  36 extern char *kmem_asprintf(const char *fmt, ...);
  37 extern char *kmem_strdup(const char *str);
  38 extern void kmem_strfree(char *str);
  39
  40 /*
  41  * Memory allocation interfaces
  42  */
  43 #define KM_SLEEP        0x0000  /* can block for memory; success guaranteed */
  44 #define KM_NOSLEEP      0x0001  /* cannot block for memory; may fail */
  45 #define KM_PUSHPAGE     0x0004  /* can block for memory; may use reserve */
  46 #define KM_ZERO         0x1000  /* zero the allocation */
  47 #define KM_VMEM         0x2000  /* caller is vmem_* wrapper */
  48
  49 #define KM_PUBLIC_MASK  (KM_SLEEP | KM_NOSLEEP | KM_PUSHPAGE)
  50
  51 static int spl_fstrans_check(void);
  52 void *spl_kvmalloc(size_t size, gfp_t flags);
  53
  54 /*
  55  * Convert a KM_* flags mask to its Linux GFP_* counterpart.  The conversion
  56  * function is context aware which means that KM_SLEEP allocations can be
  57  * safely used in syncing contexts which have set PF_FSTRANS.
  58  */
  59 static inline gfp_t
  60 kmem_flags_convert(int flags)
  61 {
  62         gfp_t lflags = __GFP_NOWARN | __GFP_COMP;
  63
  64         if (flags & KM_NOSLEEP) {
  65                 lflags |= GFP_ATOMIC | __GFP_NORETRY;
  66         } else {
  67                 lflags |= GFP_KERNEL;
  68                 if (spl_fstrans_check())
  69                         lflags &= ~(__GFP_IO|__GFP_FS);
  70         }
  71
  72         if (flags & KM_PUSHPAGE)
  73                 lflags |= __GFP_HIGH;
  74
  75         if (flags & KM_ZERO)
  76                 lflags |= __GFP_ZERO;
  77
  78         return (lflags);
  79 }
  80
  81 typedef struct {
  82         struct task_struct *fstrans_thread;
  83         unsigned int saved_flags;
  84 } fstrans_cookie_t;
  85
  86 /*
  87  * Introduced in Linux 3.9, however this cannot be solely relied on before
  88  * Linux 3.18 as it doesn't turn off __GFP_FS as it should.
  89  */
  90 #ifdef PF_MEMALLOC_NOIO
  91 #define __SPL_PF_MEMALLOC_NOIO (PF_MEMALLOC_NOIO)
  92 #else
  93 #define __SPL_PF_MEMALLOC_NOIO (0)
  94 #endif
  95
  96 /*
  97  * PF_FSTRANS is removed from Linux 4.12
  98  */
  99 #ifdef PF_FSTRANS
 100 #define __SPL_PF_FSTRANS (PF_FSTRANS)
 101 #else
 102 #define __SPL_PF_FSTRANS (0)
 103 #endif
 104
 105 #define SPL_FSTRANS (__SPL_PF_FSTRANS|__SPL_PF_MEMALLOC_NOIO)
 106
 107 static inline fstrans_cookie_t
 108 spl_fstrans_mark(void)
 109 {
 110         fstrans_cookie_t cookie;
 111
 112         BUILD_BUG_ON(SPL_FSTRANS == 0);
 113
 114         cookie.fstrans_thread = current;
 115         cookie.saved_flags = current->flags & SPL_FSTRANS;
 116         current->flags |= SPL_FSTRANS;
 117
 118         return (cookie);
 119 }
 120
 121 static inline void
 122 spl_fstrans_unmark(fstrans_cookie_t cookie)
 123 {
 124         ASSERT3P(cookie.fstrans_thread, ==, current);
 125         ASSERT((current->flags & SPL_FSTRANS) == SPL_FSTRANS);
 126
 127         current->flags &= ~SPL_FSTRANS;
 128         current->flags |= cookie.saved_flags;
 129 }
 130
 131 static inline int
 132 spl_fstrans_check(void)
 133 {
 134         return (current->flags & SPL_FSTRANS);
 135 }
 136
 137 /*
 138  * specifically used to check PF_FSTRANS flag, cannot be relied on for
 139  * checking spl_fstrans_mark().
 140  */
 141 static inline int
 142 __spl_pf_fstrans_check(void)
 143 {
 144         return (current->flags & __SPL_PF_FSTRANS);
 145 }
 146
 147 #ifdef HAVE_ATOMIC64_T
 148 #define kmem_alloc_used_add(size)       atomic64_add(size, &kmem_alloc_used)
 149 #define kmem_alloc_used_sub(size)       atomic64_sub(size, &kmem_alloc_used)
 150 #define kmem_alloc_used_read()          atomic64_read(&kmem_alloc_used)
 151 #define kmem_alloc_used_set(size)       atomic64_set(&kmem_alloc_used, size)
 152 extern atomic64_t kmem_alloc_used;
 153 extern unsigned long long kmem_alloc_max;
 154 #else  /* HAVE_ATOMIC64_T */
 155 #define kmem_alloc_used_add(size)       atomic_add(size, &kmem_alloc_used)
 156 #define kmem_alloc_used_sub(size)       atomic_sub(size, &kmem_alloc_used)
 157 #define kmem_alloc_used_read()          atomic_read(&kmem_alloc_used)
 158 #define kmem_alloc_used_set(size)       atomic_set(&kmem_alloc_used, size)
 159 extern atomic_t kmem_alloc_used;
 160 extern unsigned long long kmem_alloc_max;
 161 #endif /* HAVE_ATOMIC64_T */
 162
 163 extern unsigned int spl_kmem_alloc_warn;
 164 extern unsigned int spl_kmem_alloc_max;
 165
 166 #define kmem_alloc(sz, fl)      spl_kmem_alloc((sz), (fl), __func__, __LINE__)
 167 #define kmem_zalloc(sz, fl)     spl_kmem_zalloc((sz), (fl), __func__, __LINE__)
 168 #define kmem_free(ptr, sz)      spl_kmem_free((ptr), (sz))
 169 #define kmem_cache_reap_active  spl_kmem_cache_reap_active
 170
 171 extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
 172 extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
 173 extern void spl_kmem_free(const void *ptr, size_t sz);
 174
 175 /*
 176  * 5.8 API change, pgprot_t argument removed.
 177  */
 178 #ifdef HAVE_VMALLOC_PAGE_KERNEL
 179 #define spl_vmalloc(size, flags)        __vmalloc(size, flags, PAGE_KERNEL)
 180 #else
 181 #define spl_vmalloc(size, flags)        __vmalloc(size, flags)
 182 #endif
 183
 184 /*
 185  * The following functions are only available for internal use.
 186  */
 187 extern void *spl_kmem_alloc_impl(size_t size, int flags, int node);
 188 extern void *spl_kmem_alloc_debug(size_t size, int flags, int node);
 189 extern void *spl_kmem_alloc_track(size_t size, int flags,
 190     const char *func, int line, int node);
 191 extern void spl_kmem_free_impl(const void *buf, size_t size);
 192 extern void spl_kmem_free_debug(const void *buf, size_t size);
 193 extern void spl_kmem_free_track(const void *buf, size_t size);
 194
 195 extern int spl_kmem_init(void);
 196 extern void spl_kmem_fini(void);
 197 extern int spl_kmem_cache_reap_active(void);
 198
 199 #endif  /* _SPL_KMEM_H */