sys/dev/drm/include/linux/mm.h

   1 /*-
   2  * Copyright (c) 2010 Isilon Systems, Inc.
   3  * Copyright (c) 2010 iX Systems, Inc.
   4  * Copyright (c) 2010 Panasas, Inc.
   5  * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
   6  * Copyright (c) 2015 François Tigeot
   7  * Copyright (c) 2015 Matthew Dillon <dillon@backplane.com>
   8  * All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice unmodified, this list of conditions, and the following
  15  *    disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 #ifndef _LINUX_MM_H_
  32 #define _LINUX_MM_H_
  33
  34 #include <linux/errno.h>
  35 #include <linux/gfp.h>
  36 #include <linux/bug.h>
  37 #include <linux/kernel.h>
  38
  39 #include <asm/page.h>
  40 #include <asm/pgtable.h>
  41
  42 static inline struct vm_page *
  43 nth_page(struct vm_page *page, int n)
  44 {
  45         return page + n;
  46 }
  47
  48 #define PAGE_ALIGN(addr) round_page(addr)
  49
  50 struct vm_area_struct {
  51         vm_offset_t     vm_start;
  52         vm_offset_t     vm_end;
  53         vm_offset_t     vm_pgoff;
  54         vm_paddr_t      vm_pfn;         /* PFN For mmap. */
  55         vm_memattr_t    vm_page_prot;
  56 };
  57
  58 /*
  59  * Compute log2 of the power of two rounded up count of pages
  60  * needed for size bytes.
  61  */
  62 static inline int
  63 get_order(unsigned long size)
  64 {
  65         int order;
  66
  67         size = (size - 1) >> PAGE_SHIFT;
  68         order = 0;
  69         while (size) {
  70                 order++;
  71                 size >>= 1;
  72         }
  73         return (order);
  74 }
  75
  76 /*
  77  * This only works via mmap ops.
  78  */
  79 static inline int
  80 io_remap_pfn_range(struct vm_area_struct *vma,
  81     unsigned long addr, unsigned long pfn, unsigned long size,
  82     vm_memattr_t prot)
  83 {
  84         vma->vm_page_prot = prot;
  85         vma->vm_pfn = pfn;
  86
  87         return (0);
  88 }
  89
  90 static inline unsigned long
  91 vma_pages(struct vm_area_struct *vma)
  92 {
  93         unsigned long size;
  94
  95         size = vma->vm_end - vma->vm_start;
  96
  97         return size >> PAGE_SHIFT;
  98 }
  99
 100 #define offset_in_page(off)     ((off) & PAGE_MASK)
 101
 102 static inline void
 103 set_page_dirty(struct vm_page *page)
 104 {
 105         vm_page_dirty(page);
 106 }
 107
 108 /*
 109  * Allocate multiple contiguous pages.  The DragonFly code can only do
 110  * multiple allocations via the free page reserve.  Linux does not appear
 111  * to restrict the address space, so neither do we.
 112  */
 113 static inline struct vm_page *
 114 alloc_pages(int flags, u_int order)
 115 {
 116         size_t bytes = PAGE_SIZE << order;
 117         struct vm_page *pgs;
 118
 119         pgs = vm_page_alloc_contig(0LLU, ~0LLU, bytes, bytes, bytes,
 120                                    VM_MEMATTR_DEFAULT);
 121         kprintf("alloc_pages order %u vm_pages=%p\n", order, pgs);
 122         return pgs;
 123 }
 124
 125 /*
 126  * Free multiple contiguous pages
 127  */
 128 static inline void
 129 __free_pages(struct vm_page *pgs, u_int order)
 130 {
 131         size_t bytes = PAGE_SIZE << order;
 132
 133         vm_page_free_contig(pgs, bytes);
 134 }
 135
 136 static inline void
 137 get_page(struct vm_page *page)
 138 {
 139         vm_page_hold(page);
 140 }
 141
 142 extern vm_paddr_t Realmem;
 143
 144 static inline unsigned long get_num_physpages(void)
 145 {
 146         return Realmem / PAGE_SIZE;
 147 }
 148
 149 #endif  /* _LINUX_MM_H_ */