include/drm/drm_mm.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. USA.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  *
  27  **************************************************************************/
  28 /*
  29  * Authors:
  30  * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
  31  */
  32
  33 #ifndef _DRM_MM_H_
  34 #define _DRM_MM_H_
  35
  36 /*
  37  * Generic range manager structs
  38  */
  39 #include <linux/bug.h>
  40 #include <linux/kernel.h>
  41 #include <linux/list.h>
  42 #include <linux/spinlock.h>
  43 #ifdef CONFIG_DEBUG_FS
  44 #include <linux/seq_file.h>
  45 #endif
  46
  47 enum drm_mm_search_flags {
  48         DRM_MM_SEARCH_DEFAULT =         0,
  49         DRM_MM_SEARCH_BEST =            1 << 0,
  50         DRM_MM_SEARCH_BELOW =           1 << 1,
  51 };
  52
  53 enum drm_mm_allocator_flags {
  54         DRM_MM_CREATE_DEFAULT =         0,
  55         DRM_MM_CREATE_TOP =             1 << 0,
  56 };
  57
  58 #define DRM_MM_BOTTOMUP DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT
  59 #define DRM_MM_TOPDOWN DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP
  60
  61 struct drm_mm_node {
  62         struct list_head node_list;
  63         struct list_head hole_stack;
  64         unsigned hole_follows : 1;
  65         unsigned scanned_block : 1;
  66         unsigned scanned_prev_free : 1;
  67         unsigned scanned_next_free : 1;
  68         unsigned scanned_preceeds_hole : 1;
  69         unsigned allocated : 1;
  70         unsigned long color;
  71         u64 start;
  72         u64 size;
  73         struct drm_mm *mm;
  74 };
  75
  76 struct drm_mm {
  77         /* List of all memory nodes that immediately precede a free hole. */
  78         struct list_head hole_stack;
  79         /* head_node.node_list is the list of all memory nodes, ordered
  80          * according to the (increasing) start address of the memory node. */
  81         struct drm_mm_node head_node;
  82         unsigned int scan_check_range : 1;
  83         unsigned scan_alignment;
  84         unsigned long scan_color;
  85         u64 scan_size;
  86         u64 scan_hit_start;
  87         u64 scan_hit_end;
  88         unsigned scanned_blocks;
  89         u64 scan_start;
  90         u64 scan_end;
  91         struct drm_mm_node *prev_scanned_node;
  92
  93         void (*color_adjust)(struct drm_mm_node *node, unsigned long color,
  94                              u64 *start, u64 *end);
  95 };
  96
  97 /**
  98  * drm_mm_node_allocated - checks whether a node is allocated
  99  * @node: drm_mm_node to check
 100  *
 101  * Drivers should use this helpers for proper encapusulation of drm_mm
 102  * internals.
 103  *
 104  * Returns:
 105  * True if the @node is allocated.
 106  */
 107 static inline bool drm_mm_node_allocated(struct drm_mm_node *node)
 108 {
 109         return node->allocated;
 110 }
 111
 112 /**
 113  * drm_mm_initialized - checks whether an allocator is initialized
 114  * @mm: drm_mm to check
 115  *
 116  * Drivers should use this helpers for proper encapusulation of drm_mm
 117  * internals.
 118  *
 119  * Returns:
 120  * True if the @mm is initialized.
 121  */
 122 static inline bool drm_mm_initialized(struct drm_mm *mm)
 123 {
 124         return mm->hole_stack.next;
 125 }
 126
 127 static inline u64 __drm_mm_hole_node_start(struct drm_mm_node *hole_node)
 128 {
 129         return hole_node->start + hole_node->size;
 130 }
 131
 132 /**
 133  * drm_mm_hole_node_start - computes the start of the hole following @node
 134  * @hole_node: drm_mm_node which implicitly tracks the following hole
 135  *
 136  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
 137  * inspect holes themselves. Drivers must check first whether a hole indeed
 138  * follows by looking at node->hole_follows.
 139  *
 140  * Returns:
 141  * Start of the subsequent hole.
 142  */
 143 static inline u64 drm_mm_hole_node_start(struct drm_mm_node *hole_node)
 144 {
 145         BUG_ON(!hole_node->hole_follows);
 146         return __drm_mm_hole_node_start(hole_node);
 147 }
 148
 149 static inline u64 __drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 150 {
 151         return list_entry(hole_node->node_list.next,
 152                           struct drm_mm_node, node_list)->start;
 153 }
 154
 155 /**
 156  * drm_mm_hole_node_end - computes the end of the hole following @node
 157  * @hole_node: drm_mm_node which implicitly tracks the following hole
 158  *
 159  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
 160  * inspect holes themselves. Drivers must check first whether a hole indeed
 161  * follows by looking at node->hole_follows.
 162  *
 163  * Returns:
 164  * End of the subsequent hole.
 165  */
 166 static inline u64 drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 167 {
 168         return __drm_mm_hole_node_end(hole_node);
 169 }
 170
 171 /**
 172  * drm_mm_for_each_node - iterator to walk over all allocated nodes
 173  * @entry: drm_mm_node structure to assign to in each iteration step
 174  * @mm: drm_mm allocator to walk
 175  *
 176  * This iterator walks over all nodes in the range allocator. It is implemented
 177  * with list_for_each, so not save against removal of elements.
 178  */
 179 #define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
 180                                                 &(mm)->head_node.node_list, \
 181                                                 node_list)
 182
 183 /**
 184  * drm_mm_for_each_hole - iterator to walk over all holes
 185  * @entry: drm_mm_node used internally to track progress
 186  * @mm: drm_mm allocator to walk
 187  * @hole_start: ulong variable to assign the hole start to on each iteration
 188  * @hole_end: ulong variable to assign the hole end to on each iteration
 189  *
 190  * This iterator walks over all holes in the range allocator. It is implemented
 191  * with list_for_each, so not save against removal of elements. @entry is used
 192  * internally and will not reflect a real drm_mm_node for the very first hole.
 193  * Hence users of this iterator may not access it.
 194  *
 195  * Implementation Note:
 196  * We need to inline list_for_each_entry in order to be able to set hole_start
 197  * and hole_end on each iteration while keeping the macro sane.
 198  *
 199  * The __drm_mm_for_each_hole version is similar, but with added support for
 200  * going backwards.
 201  */
 202 #define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
 203         for (entry = list_entry((mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
 204              &entry->hole_stack != &(mm)->hole_stack ? \
 205              hole_start = drm_mm_hole_node_start(entry), \
 206              hole_end = drm_mm_hole_node_end(entry), \
 207              1 : 0; \
 208              entry = list_entry(entry->hole_stack.next, struct drm_mm_node, hole_stack))
 209
 210 #define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
 211         for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
 212              &entry->hole_stack != &(mm)->hole_stack ? \
 213              hole_start = drm_mm_hole_node_start(entry), \
 214              hole_end = drm_mm_hole_node_end(entry), \
 215              1 : 0; \
 216              entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
 217
 218 /*
 219  * Basic range manager support (drm_mm.c)
 220  */
 221 int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
 222
 223 int drm_mm_insert_node_generic(struct drm_mm *mm,
 224                                struct drm_mm_node *node,
 225                                u64 size,
 226                                unsigned alignment,
 227                                unsigned long color,
 228                                enum drm_mm_search_flags sflags,
 229                                enum drm_mm_allocator_flags aflags);
 230 /**
 231  * drm_mm_insert_node - search for space and insert @node
 232  * @mm: drm_mm to allocate from
 233  * @node: preallocate node to insert
 234  * @size: size of the allocation
 235  * @alignment: alignment of the allocation
 236  * @flags: flags to fine-tune the allocation
 237  *
 238  * This is a simplified version of drm_mm_insert_node_generic() with @color set
 239  * to 0.
 240  *
 241  * The preallocated node must be cleared to 0.
 242  *
 243  * Returns:
 244  * 0 on success, -ENOSPC if there's no suitable hole.
 245  */
 246 static inline int drm_mm_insert_node(struct drm_mm *mm,
 247                                      struct drm_mm_node *node,
 248                                      u64 size,
 249                                      unsigned alignment,
 250                                      enum drm_mm_search_flags flags)
 251 {
 252         return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags,
 253                                           DRM_MM_CREATE_DEFAULT);
 254 }
 255
 256 int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
 257                                         struct drm_mm_node *node,
 258                                         u64 size,
 259                                         unsigned alignment,
 260                                         unsigned long color,
 261                                         u64 start,
 262                                         u64 end,
 263                                         enum drm_mm_search_flags sflags,
 264                                         enum drm_mm_allocator_flags aflags);
 265 /**
 266  * drm_mm_insert_node_in_range - ranged search for space and insert @node
 267  * @mm: drm_mm to allocate from
 268  * @node: preallocate node to insert
 269  * @size: size of the allocation
 270  * @alignment: alignment of the allocation
 271  * @start: start of the allowed range for this node
 272  * @end: end of the allowed range for this node
 273  * @flags: flags to fine-tune the allocation
 274  *
 275  * This is a simplified version of drm_mm_insert_node_in_range_generic() with
 276  * @color set to 0.
 277  *
 278  * The preallocated node must be cleared to 0.
 279  *
 280  * Returns:
 281  * 0 on success, -ENOSPC if there's no suitable hole.
 282  */
 283 static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
 284                                               struct drm_mm_node *node,
 285                                               u64 size,
 286                                               unsigned alignment,
 287                                               u64 start,
 288                                               u64 end,
 289                                               enum drm_mm_search_flags flags)
 290 {
 291         return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
 292                                                    0, start, end, flags,
 293                                                    DRM_MM_CREATE_DEFAULT);
 294 }
 295
 296 void drm_mm_remove_node(struct drm_mm_node *node);
 297 void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
 298 void drm_mm_init(struct drm_mm *mm,
 299                  u64 start,
 300                  u64 size);
 301 void drm_mm_takedown(struct drm_mm *mm);
 302 bool drm_mm_clean(struct drm_mm *mm);
 303
 304 void drm_mm_init_scan(struct drm_mm *mm,
 305                       u64 size,
 306                       unsigned alignment,
 307                       unsigned long color);
 308 void drm_mm_init_scan_with_range(struct drm_mm *mm,
 309                                  u64 size,
 310                                  unsigned alignment,
 311                                  unsigned long color,
 312                                  u64 start,
 313                                  u64 end);
 314 bool drm_mm_scan_add_block(struct drm_mm_node *node);
 315 bool drm_mm_scan_remove_block(struct drm_mm_node *node);
 316
 317 void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
 318 #ifdef CONFIG_DEBUG_FS
 319 int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
 320 #endif
 321
 322 #endif