include/sys/vmsystm.h

   1 /*
   2  *  This file is part of the SPL: Solaris Porting Layer.
   3  *
   4  *  Copyright (c) 2008 Lawrence Livermore National Security, LLC.
   5  *  Produced at Lawrence Livermore National Laboratory
   6  *  Written by:
   7  *          Brian Behlendorf <behlendorf1@llnl.gov>,
   8  *          Herb Wartens <wartens2@llnl.gov>,
   9  *          Jim Garlick <garlick@llnl.gov>
  10  *  UCRL-CODE-235197
  11  *
  12  *  This is free software; you can redistribute it and/or modify it
  13  *  under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  16  *
  17  *  This is distributed in the hope that it will be useful, but WITHOUT
  18  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  *  for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  25  */
  26
  27 #ifndef _SPL_VMSYSTM_H
  28 #define _SPL_VMSYSTM_H
  29
  30 #include <linux/mmzone.h>
  31 #include <linux/mm.h>
  32 #include <linux/swap.h>
  33 #include <sys/types.h>
  34 #include <asm/uaccess.h>
  35
  36 /* These values are loosely coupled with the the VM page reclaim.
  37  * Linux uses its own heuristics to trigger page reclamation, and
  38  * because those interface are difficult to interface with.  These
  39  * values should only be considered as a rough guide to the system
  40  * memory state and not as direct evidence that page reclaimation
  41  * is or is not currently in progress.
  42  */
  43 #define ptob(pages)                     (pages * PAGE_SIZE)
  44 #define membar_producer()               smp_wmb()
  45
  46 #define physmem                         num_physpages
  47 #define freemem                         nr_free_pages()
  48 #define availrmem                       spl_kmem_availrmem()
  49
  50 extern pgcnt_t minfree;                 /* Sum of zone->pages_min */
  51 extern pgcnt_t desfree;                 /* Sum of zone->pages_low */
  52 extern pgcnt_t lotsfree;                /* Sum of zone->pages_high */
  53 extern pgcnt_t needfree;                /* Always 0 unused in new Solaris */
  54 extern pgcnt_t swapfs_minfree;          /* Solaris default value */
  55 extern pgcnt_t swapfs_reserve;          /* Solaris default value */
  56
  57 extern vmem_t *heap_arena;              /* primary kernel heap arena */
  58 extern vmem_t *zio_alloc_arena;         /* arena for zio caches */
  59 extern vmem_t *zio_arena;               /* arena for allocating zio memory */
  60
  61 #define VMEM_ALLOC                      0x01
  62 #define VMEM_FREE                       0x02
  63
  64 extern pgcnt_t spl_kmem_availrmem(void);
  65 extern size_t vmem_size(vmem_t *vmp, int typemask);
  66
  67 #define xcopyin(from, to, size)         copy_from_user(to, from, size)
  68 #define xcopyout(from, to, size)        copy_to_user(to, from, size)
  69
  70 static __inline__ int
  71 copyin(const void *from, void *to, size_t len)
  72 {
  73         /* On error copyin routine returns -1 */
  74         if (xcopyin(from, to, len))
  75                 return -1;
  76
  77         return 0;
  78 }
  79
  80 static __inline__ int
  81 copyout(const void *from, void *to, size_t len)
  82 {
  83         /* On error copyout routine returns -1 */
  84         if (xcopyout(from, to, len))
  85                 return -1;
  86
  87         return 0;
  88 }
  89
  90 static __inline__ int
  91 copyinstr(const void *from, void *to, size_t len, size_t *done)
  92 {
  93         size_t rc;
  94
  95         if (len == 0)
  96                 return -ENAMETOOLONG;
  97
  98         /* XXX: Should return ENAMETOOLONG if 'strlen(from) > len' */
  99
 100         memset(to, 0, len);
 101         rc = copyin(from, to, len - 1);
 102         if (done != NULL)
 103                 *done = rc;
 104
 105         return 0;
 106 }
 107
 108 #endif /* SPL_VMSYSTM_H */