drivers/gpu/drm/nouveau/nouveau_mm.c

   1 /*
   2  * Copyright 2010 Red Hat Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * Authors: Ben Skeggs
  23  */
  24
  25 #include "drmP.h"
  26 #include "nouveau_drv.h"
  27 #include "nouveau_mm.h"
  28
  29 static inline void
  30 region_put(struct nouveau_mm *rmm, struct nouveau_mm_node *a)
  31 {
  32         list_del(&a->nl_entry);
  33         list_del(&a->fl_entry);
  34         kfree(a);
  35 }
  36
  37 static struct nouveau_mm_node *
  38 region_split(struct nouveau_mm *rmm, struct nouveau_mm_node *a, u32 size)
  39 {
  40         struct nouveau_mm_node *b;
  41
  42         if (a->length == size)
  43                 return a;
  44
  45         b = kmalloc(sizeof(*b), GFP_KERNEL);
  46         if (unlikely(b == NULL))
  47                 return NULL;
  48
  49         b->offset = a->offset;
  50         b->length = size;
  51         b->type   = a->type;
  52         a->offset += size;
  53         a->length -= size;
  54         list_add_tail(&b->nl_entry, &a->nl_entry);
  55         if (b->type == 0)
  56                 list_add_tail(&b->fl_entry, &a->fl_entry);
  57         return b;
  58 }
  59
  60 #define node(root, dir) ((root)->nl_entry.dir == &rmm->nodes) ? NULL : \
  61         list_entry((root)->nl_entry.dir, struct nouveau_mm_node, nl_entry)
  62
  63 void
  64 nouveau_mm_put(struct nouveau_mm *rmm, struct nouveau_mm_node *this)
  65 {
  66         struct nouveau_mm_node *prev = node(this, prev);
  67         struct nouveau_mm_node *next = node(this, next);
  68
  69         list_add(&this->fl_entry, &rmm->free);
  70         this->type = 0;
  71
  72         if (prev && prev->type == 0) {
  73                 prev->length += this->length;
  74                 region_put(rmm, this);
  75                 this = prev;
  76         }
  77
  78         if (next && next->type == 0) {
  79                 next->offset  = this->offset;
  80                 next->length += this->length;
  81                 region_put(rmm, this);
  82         }
  83 }
  84
  85 int
  86 nouveau_mm_get(struct nouveau_mm *rmm, int type, u32 size, u32 size_nc,
  87                u32 align, struct nouveau_mm_node **pnode)
  88 {
  89         struct nouveau_mm_node *prev, *this, *next;
  90         u32 min = size_nc ? size_nc : size;
  91         u32 align_mask = align - 1;
  92         u32 splitoff;
  93         u32 s, e;
  94
  95         list_for_each_entry(this, &rmm->free, fl_entry) {
  96                 e = this->offset + this->length;
  97                 s = this->offset;
  98
  99                 prev = node(this, prev);
 100                 if (prev && prev->type != type)
 101                         s = roundup(s, rmm->block_size);
 102
 103                 next = node(this, next);
 104                 if (next && next->type != type)
 105                         e = rounddown(e, rmm->block_size);
 106
 107                 s  = (s + align_mask) & ~align_mask;
 108                 e &= ~align_mask;
 109                 if (s > e || e - s < min)
 110                         continue;
 111
 112                 splitoff = s - this->offset;
 113                 if (splitoff && !region_split(rmm, this, splitoff))
 114                         return -ENOMEM;
 115
 116                 this = region_split(rmm, this, min(size, e - s));
 117                 if (!this)
 118                         return -ENOMEM;
 119
 120                 this->type = type;
 121                 list_del(&this->fl_entry);
 122                 *pnode = this;
 123                 return 0;
 124         }
 125
 126         return -ENOSPC;
 127 }
 128
 129 int
 130 nouveau_mm_init(struct nouveau_mm **prmm, u32 offset, u32 length, u32 block)
 131 {
 132         struct nouveau_mm *rmm;
 133         struct nouveau_mm_node *heap;
 134
 135         heap = kzalloc(sizeof(*heap), GFP_KERNEL);
 136         if (!heap)
 137                 return -ENOMEM;
 138         heap->offset = roundup(offset, block);
 139         heap->length = rounddown(offset + length, block) - heap->offset;
 140
 141         rmm = kzalloc(sizeof(*rmm), GFP_KERNEL);
 142         if (!rmm) {
 143                 kfree(heap);
 144                 return -ENOMEM;
 145         }
 146         rmm->block_size = block;
 147         mutex_init(&rmm->mutex);
 148         INIT_LIST_HEAD(&rmm->nodes);
 149         INIT_LIST_HEAD(&rmm->free);
 150         list_add(&heap->nl_entry, &rmm->nodes);
 151         list_add(&heap->fl_entry, &rmm->free);
 152
 153         *prmm = rmm;
 154         return 0;
 155 }
 156
 157 int
 158 nouveau_mm_fini(struct nouveau_mm **prmm)
 159 {
 160         struct nouveau_mm *rmm = *prmm;
 161         struct nouveau_mm_node *heap =
 162                 list_first_entry(&rmm->nodes, struct nouveau_mm_node, nl_entry);
 163
 164         if (!list_is_singular(&rmm->nodes))
 165                 return -EBUSY;
 166
 167         kfree(heap);
 168         kfree(rmm);
 169         *prmm = NULL;
 170         return 0;
 171 }