module/spl/spl-vmem.c

   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 #include <sys/debug.h>
  26 #include <sys/vmem.h>
  27 #include <sys/kmem_cache.h>
  28 #include <sys/shrinker.h>
  29 #include <linux/module.h>
  30
  31 vmem_t *heap_arena = NULL;
  32 EXPORT_SYMBOL(heap_arena);
  33
  34 vmem_t *zio_alloc_arena = NULL;
  35 EXPORT_SYMBOL(zio_alloc_arena);
  36
  37 vmem_t *zio_arena = NULL;
  38 EXPORT_SYMBOL(zio_arena);
  39
  40 #define VMEM_FLOOR_SIZE         (4 * 1024 * 1024)       /* 4MB floor */
  41
  42 /*
  43  * Return approximate virtual memory usage based on these assumptions:
  44  *
  45  * 1) The major SPL consumer of virtual memory is the kmem cache.
  46  * 2) Memory allocated with vmem_alloc() is short lived and can be ignored.
  47  * 3) Allow a 4MB floor as a generous pad given normal consumption.
  48  * 4) The spl_kmem_cache_sem only contends with cache create/destroy.
  49  */
  50 size_t
  51 vmem_size(vmem_t *vmp, int typemask)
  52 {
  53         spl_kmem_cache_t *skc;
  54         size_t alloc = VMEM_FLOOR_SIZE;
  55
  56         if ((typemask & VMEM_ALLOC) && (typemask & VMEM_FREE))
  57                 return (VMALLOC_TOTAL);
  58
  59
  60         down_read(&spl_kmem_cache_sem);
  61         list_for_each_entry(skc, &spl_kmem_cache_list, skc_list) {
  62                 if (skc->skc_flags & KMC_VMEM)
  63                         alloc += skc->skc_slab_size * skc->skc_slab_total;
  64         }
  65         up_read(&spl_kmem_cache_sem);
  66
  67         if (typemask & VMEM_ALLOC)
  68                 return (MIN(alloc, VMALLOC_TOTAL));
  69         else if (typemask & VMEM_FREE)
  70                 return (MAX(VMALLOC_TOTAL - alloc, 0));
  71         else
  72                 return (0);
  73 }
  74 EXPORT_SYMBOL(vmem_size);
  75
  76 /*
  77  * Public vmem_alloc(), vmem_zalloc() and vmem_free() interfaces.
  78  */
  79 void *
  80 spl_vmem_alloc(size_t size, int flags, const char *func, int line)
  81 {
  82         ASSERT0(flags & ~KM_PUBLIC_MASK);
  83
  84         flags |= KM_VMEM;
  85
  86 #if !defined(DEBUG_KMEM)
  87         return (spl_kmem_alloc_impl(size, flags, NUMA_NO_NODE));
  88 #elif !defined(DEBUG_KMEM_TRACKING)
  89         return (spl_kmem_alloc_debug(size, flags, NUMA_NO_NODE));
  90 #else
  91         return (spl_kmem_alloc_track(size, flags, func, line, NUMA_NO_NODE));
  92 #endif
  93 }
  94 EXPORT_SYMBOL(spl_vmem_alloc);
  95
  96 void *
  97 spl_vmem_zalloc(size_t size, int flags, const char *func, int line)
  98 {
  99         ASSERT0(flags & ~KM_PUBLIC_MASK);
 100
 101         flags |= (KM_VMEM | KM_ZERO);
 102
 103 #if !defined(DEBUG_KMEM)
 104         return (spl_kmem_alloc_impl(size, flags, NUMA_NO_NODE));
 105 #elif !defined(DEBUG_KMEM_TRACKING)
 106         return (spl_kmem_alloc_debug(size, flags, NUMA_NO_NODE));
 107 #else
 108         return (spl_kmem_alloc_track(size, flags, func, line, NUMA_NO_NODE));
 109 #endif
 110 }
 111 EXPORT_SYMBOL(spl_vmem_zalloc);
 112
 113 void
 114 spl_vmem_free(const void *buf, size_t size)
 115 {
 116 #if !defined(DEBUG_KMEM)
 117         return (spl_kmem_free_impl(buf, size));
 118 #elif !defined(DEBUG_KMEM_TRACKING)
 119         return (spl_kmem_free_debug(buf, size));
 120 #else
 121         return (spl_kmem_free_track(buf, size));
 122 #endif
 123 }
 124 EXPORT_SYMBOL(spl_vmem_free);
 125
 126 int
 127 spl_vmem_init(void)
 128 {
 129         return (0);
 130 }
 131
 132 void
 133 spl_vmem_fini(void)
 134 {
 135 }