include/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
  32 extern int kmem_debugging(void);
  33 extern char *kmem_vasprintf(const char *fmt, va_list ap);
  34 extern char *kmem_asprintf(const char *fmt, ...);
  35 extern char *strdup(const char *str);
  36 extern void strfree(char *str);
  37
  38 /*
  39  * Memory allocation interfaces
  40  */
  41 #define KM_SLEEP        0x0000  /* can block for memory; success guaranteed */
  42 #define KM_NOSLEEP      0x0001  /* cannot block for memory; may fail */
  43 #define KM_PUSHPAGE     0x0004  /* can block for memory; may use reserve */
  44 #define KM_ZERO         0x1000  /* zero the allocation */
  45 #define KM_VMEM         0x2000  /* caller is vmem_* wrapper */
  46
  47 #define KM_PUBLIC_MASK  (KM_SLEEP | KM_NOSLEEP | KM_PUSHPAGE)
  48
  49 /*
  50  * Convert a KM_* flags mask to its Linux GFP_* counterpart.  The conversion
  51  * function is context aware which means that KM_SLEEP allocations can be
  52  * safely used in syncing contexts which have set PF_FSTRANS.
  53  */
  54 static inline gfp_t
  55 kmem_flags_convert(int flags)
  56 {
  57         gfp_t lflags = __GFP_NOWARN | __GFP_COMP;
  58
  59         if (flags & KM_NOSLEEP) {
  60                 lflags |= GFP_ATOMIC | __GFP_NORETRY;
  61         } else {
  62                 lflags |= GFP_KERNEL;
  63                 if ((current->flags & PF_FSTRANS))
  64                         lflags &= ~(__GFP_IO|__GFP_FS);
  65         }
  66
  67         if (flags & KM_PUSHPAGE)
  68                 lflags |= __GFP_HIGH;
  69
  70         if (flags & KM_ZERO)
  71                 lflags |= __GFP_ZERO;
  72
  73         return (lflags);
  74 }
  75
  76 typedef struct {
  77         struct task_struct *fstrans_thread;
  78         unsigned int saved_flags;
  79 } fstrans_cookie_t;
  80
  81 #ifdef PF_MEMALLOC_NOIO
  82 #define SPL_FSTRANS (PF_FSTRANS|PF_MEMALLOC_NOIO)
  83 #else
  84 #define SPL_FSTRANS (PF_FSTRANS)
  85 #endif
  86
  87 static inline fstrans_cookie_t
  88 spl_fstrans_mark(void)
  89 {
  90         fstrans_cookie_t cookie;
  91
  92         cookie.fstrans_thread = current;
  93         cookie.saved_flags = current->flags & SPL_FSTRANS;
  94         current->flags |= SPL_FSTRANS;
  95
  96         return (cookie);
  97 }
  98
  99 static inline void
 100 spl_fstrans_unmark(fstrans_cookie_t cookie)
 101 {
 102         ASSERT3P(cookie.fstrans_thread, ==, current);
 103         ASSERT((current->flags & SPL_FSTRANS) == SPL_FSTRANS);
 104
 105         current->flags &= ~SPL_FSTRANS;
 106         current->flags |= cookie.saved_flags;
 107 }
 108
 109 static inline int
 110 spl_fstrans_check(void)
 111 {
 112         return (current->flags & PF_FSTRANS);
 113 }
 114
 115 #ifdef HAVE_ATOMIC64_T
 116 #define kmem_alloc_used_add(size)       atomic64_add(size, &kmem_alloc_used)
 117 #define kmem_alloc_used_sub(size)       atomic64_sub(size, &kmem_alloc_used)
 118 #define kmem_alloc_used_read()          atomic64_read(&kmem_alloc_used)
 119 #define kmem_alloc_used_set(size)       atomic64_set(&kmem_alloc_used, size)
 120 extern atomic64_t kmem_alloc_used;
 121 extern unsigned long long kmem_alloc_max;
 122 #else  /* HAVE_ATOMIC64_T */
 123 #define kmem_alloc_used_add(size)       atomic_add(size, &kmem_alloc_used)
 124 #define kmem_alloc_used_sub(size)       atomic_sub(size, &kmem_alloc_used)
 125 #define kmem_alloc_used_read()          atomic_read(&kmem_alloc_used)
 126 #define kmem_alloc_used_set(size)       atomic_set(&kmem_alloc_used, size)
 127 extern atomic_t kmem_alloc_used;
 128 extern unsigned long long kmem_alloc_max;
 129 #endif /* HAVE_ATOMIC64_T */
 130
 131 extern unsigned int spl_kmem_alloc_warn;
 132 extern unsigned int spl_kmem_alloc_max;
 133
 134 #define kmem_alloc(sz, fl)      spl_kmem_alloc((sz), (fl), __func__, __LINE__)
 135 #define kmem_zalloc(sz, fl)     spl_kmem_zalloc((sz), (fl), __func__, __LINE__)
 136 #define kmem_free(ptr, sz)      spl_kmem_free((ptr), (sz))
 137
 138 extern void *spl_kmem_alloc(size_t sz, int fl, const char *func, int line);
 139 extern void *spl_kmem_zalloc(size_t sz, int fl, const char *func, int line);
 140 extern void spl_kmem_free(const void *ptr, size_t sz);
 141
 142 /*
 143  * The following functions are only available for internal use.
 144  */
 145 extern void *spl_kmem_alloc_impl(size_t size, int flags, int node);
 146 extern void *spl_kmem_alloc_debug(size_t size, int flags, int node);
 147 extern void *spl_kmem_alloc_track(size_t size, int flags,
 148     const char *func, int line, int node);
 149 extern void spl_kmem_free_impl(const void *buf, size_t size);
 150 extern void spl_kmem_free_debug(const void *buf, size_t size);
 151 extern void spl_kmem_free_track(const void *buf, size_t size);
 152
 153 extern int spl_kmem_init(void);
 154 extern void spl_kmem_fini(void);
 155
 156 #endif  /* _SPL_KMEM_H */