sys/dev/drm/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         struct list_head unused_nodes;
  83         int num_unused;
  84         struct spinlock unused_lock;
  85         unsigned int scan_check_range : 1;
  86         unsigned scan_alignment;
  87         unsigned long scan_color;
  88         unsigned long scan_size;
  89         unsigned long scan_hit_start;
  90         unsigned long scan_hit_end;
  91         unsigned scanned_blocks;
  92         unsigned long scan_start;
  93         unsigned long scan_end;
  94         struct drm_mm_node *prev_scanned_node;
  95
  96         void (*color_adjust)(struct drm_mm_node *node, unsigned long color,
  97                              unsigned long *start, unsigned long *end);
  98 };
  99
 100 /**
 101  * drm_mm_node_allocated - checks whether a node is allocated
 102  * @node: drm_mm_node to check
 103  *
 104  * Drivers should use this helpers for proper encapusulation of drm_mm
 105  * internals.
 106  *
 107  * Returns:
 108  * True if the @node is allocated.
 109  */
 110 static inline bool drm_mm_node_allocated(struct drm_mm_node *node)
 111 {
 112         return node->allocated;
 113 }
 114
 115 /**
 116  * drm_mm_initialized - checks whether an allocator is initialized
 117  * @mm: drm_mm to check
 118  *
 119  * Drivers should use this helpers for proper encapusulation of drm_mm
 120  * internals.
 121  *
 122  * Returns:
 123  * True if the @mm is initialized.
 124  */
 125 static inline bool drm_mm_initialized(struct drm_mm *mm)
 126 {
 127         return mm->hole_stack.next;
 128 }
 129
 130 static inline u64 __drm_mm_hole_node_start(struct drm_mm_node *hole_node)
 131 {
 132         return hole_node->start + hole_node->size;
 133 }
 134
 135 /**
 136  * drm_mm_hole_node_start - computes the start of the hole following @node
 137  * @hole_node: drm_mm_node which implicitly tracks the following hole
 138  *
 139  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
 140  * inspect holes themselves. Drivers must check first whether a hole indeed
 141  * follows by looking at node->hole_follows.
 142  *
 143  * Returns:
 144  * Start of the subsequent hole.
 145  */
 146 static inline u64 drm_mm_hole_node_start(struct drm_mm_node *hole_node)
 147 {
 148         BUG_ON(!hole_node->hole_follows);
 149         return __drm_mm_hole_node_start(hole_node);
 150 }
 151
 152 static inline unsigned long __drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 153 {
 154         return list_entry(hole_node->node_list.next,
 155                           struct drm_mm_node, node_list)->start;
 156 }
 157
 158 /**
 159  * drm_mm_hole_node_end - computes the end of the hole following @node
 160  * @hole_node: drm_mm_node which implicitly tracks the following hole
 161  *
 162  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
 163  * inspect holes themselves. Drivers must check first whether a hole indeed
 164  * follows by looking at node->hole_follows.
 165  *
 166  * Returns:
 167  * End of the subsequent hole.
 168  */
 169 static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 170 {
 171         return __drm_mm_hole_node_end(hole_node);
 172 }
 173
 174 /**
 175  * drm_mm_for_each_node - iterator to walk over all allocated nodes
 176  * @entry: drm_mm_node structure to assign to in each iteration step
 177  * @mm: drm_mm allocator to walk
 178  *
 179  * This iterator walks over all nodes in the range allocator. It is implemented
 180  * with list_for_each, so not save against removal of elements.
 181  */
 182 #define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
 183                                                 &(mm)->head_node.node_list, \
 184                                                 node_list)
 185
 186 /**
 187  * drm_mm_for_each_hole - iterator to walk over all holes
 188  * @entry: drm_mm_node used internally to track progress
 189  * @mm: drm_mm allocator to walk
 190  * @hole_start: ulong variable to assign the hole start to on each iteration
 191  * @hole_end: ulong variable to assign the hole end to on each iteration
 192  *
 193  * This iterator walks over all holes in the range allocator. It is implemented
 194  * with list_for_each, so not save against removal of elements. @entry is used
 195  * internally and will not reflect a real drm_mm_node for the very first hole.
 196  * Hence users of this iterator may not access it.
 197  *
 198  * Implementation Note:
 199  * We need to inline list_for_each_entry in order to be able to set hole_start
 200  * and hole_end on each iteration while keeping the macro sane.
 201  *
 202  * The __drm_mm_for_each_hole version is similar, but with added support for
 203  * going backwards.
 204  */
 205 #define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
 206         for (entry = list_entry((mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
 207              &entry->hole_stack != &(mm)->hole_stack ? \
 208              hole_start = drm_mm_hole_node_start(entry), \
 209              hole_end = drm_mm_hole_node_end(entry), \
 210              1 : 0; \
 211              entry = list_entry(entry->hole_stack.next, struct drm_mm_node, hole_stack))
 212
 213 #define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
 214         for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
 215              &entry->hole_stack != &(mm)->hole_stack ? \
 216              hole_start = drm_mm_hole_node_start(entry), \
 217              hole_end = drm_mm_hole_node_end(entry), \
 218              1 : 0; \
 219              entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
 220
 221 /*
 222  * Basic range manager support (drm_mm.c)
 223  */
 224 int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
 225
 226 extern struct drm_mm_node *drm_mm_get_block_generic(struct drm_mm_node *node,
 227                                                     unsigned long size,
 228                                                     unsigned alignment,
 229                                                     unsigned long color,
 230                                                     int atomic);
 231 extern struct drm_mm_node *drm_mm_get_block_range_generic(
 232                                                 struct drm_mm_node *node,
 233                                                 unsigned long size,
 234                                                 unsigned alignment,
 235                                                 unsigned long color,
 236                                                 unsigned long start,
 237                                                 unsigned long end,
 238                                                 int atomic);
 239
 240 static inline struct drm_mm_node *drm_mm_get_block_atomic(struct drm_mm_node *parent,
 241                                                           unsigned long size,
 242                                                           unsigned alignment)
 243 {
 244         return drm_mm_get_block_generic(parent, size, alignment, 0, 1);
 245 }
 246
 247 static inline struct drm_mm_node *drm_mm_get_block_atomic_range(
 248                                                 struct drm_mm_node *parent,
 249                                                 unsigned long size,
 250                                                 unsigned alignment,
 251                                                 unsigned long start,
 252                                                 unsigned long end)
 253 {
 254         return drm_mm_get_block_range_generic(parent, size, alignment, 0,
 255                                                 start, end, 1);
 256 }
 257
 258 int drm_mm_insert_node_generic(struct drm_mm *mm,
 259                                struct drm_mm_node *node,
 260                                unsigned long size,
 261                                unsigned alignment,
 262                                unsigned long color,
 263                                enum drm_mm_search_flags sflags,
 264                                enum drm_mm_allocator_flags aflags);
 265 /**
 266  * drm_mm_insert_node - 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  * @flags: flags to fine-tune the allocation
 272  *
 273  * This is a simplified version of drm_mm_insert_node_generic() with @color set
 274  * to 0.
 275  *
 276  * The preallocated node must be cleared to 0.
 277  *
 278  * Returns:
 279  * 0 on success, -ENOSPC if there's no suitable hole.
 280  */
 281 static inline int drm_mm_insert_node(struct drm_mm *mm,
 282                                      struct drm_mm_node *node,
 283                                      unsigned long size,
 284                                      unsigned alignment,
 285                                      enum drm_mm_search_flags flags)
 286 {
 287         return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags,
 288                                           DRM_MM_CREATE_DEFAULT);
 289 }
 290
 291 int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
 292                                         struct drm_mm_node *node,
 293                                         unsigned long size,
 294                                         unsigned alignment,
 295                                         unsigned long color,
 296                                         unsigned long start,
 297                                         unsigned long end,
 298                                         enum drm_mm_search_flags sflags,
 299                                         enum drm_mm_allocator_flags aflags);
 300 /**
 301  * drm_mm_insert_node_in_range - ranged search for space and insert @node
 302  * @mm: drm_mm to allocate from
 303  * @node: preallocate node to insert
 304  * @size: size of the allocation
 305  * @alignment: alignment of the allocation
 306  * @start: start of the allowed range for this node
 307  * @end: end of the allowed range for this node
 308  * @flags: flags to fine-tune the allocation
 309  *
 310  * This is a simplified version of drm_mm_insert_node_in_range_generic() with
 311  * @color set to 0.
 312  *
 313  * The preallocated node must be cleared to 0.
 314  *
 315  * Returns:
 316  * 0 on success, -ENOSPC if there's no suitable hole.
 317  */
 318 static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
 319                                               struct drm_mm_node *node,
 320                                               unsigned long size,
 321                                               unsigned alignment,
 322                                               unsigned long start,
 323                                               unsigned long end,
 324                                               enum drm_mm_search_flags flags)
 325 {
 326         return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
 327                                                    0, start, end, flags,
 328                                                    DRM_MM_CREATE_DEFAULT);
 329 }
 330
 331 extern void drm_mm_put_block(struct drm_mm_node *cur);
 332
 333 extern struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm,
 334                                                       unsigned long size,
 335                                                       unsigned alignment,
 336                                                       unsigned long color,
 337                                                       enum drm_mm_search_flags flags);
 338 extern struct drm_mm_node *drm_mm_search_free_in_range_generic(
 339                                                 const struct drm_mm *mm,
 340                                                 unsigned long size,
 341                                                 unsigned alignment,
 342                                                 unsigned long color,
 343                                                 unsigned long start,
 344                                                 unsigned long end,
 345                                                 enum drm_mm_search_flags flags);
 346 static inline struct drm_mm_node *drm_mm_search_free(const struct drm_mm *mm,
 347                                                      unsigned long size,
 348                                                      unsigned alignment,
 349                                                      enum drm_mm_search_flags flags)
 350 {
 351         return drm_mm_search_free_generic(mm,size, alignment, 0, flags);
 352 }
 353 static inline  struct drm_mm_node *drm_mm_search_free_in_range(
 354                                                 const struct drm_mm *mm,
 355                                                 unsigned long size,
 356                                                 unsigned alignment,
 357                                                 unsigned long start,
 358                                                 unsigned long end,
 359                                                 enum drm_mm_search_flags flags)
 360 {
 361         return drm_mm_search_free_in_range_generic(mm, size, alignment, 0,
 362                                                    start, end, flags);
 363 }
 364
 365 extern int drm_mm_pre_get(struct drm_mm *mm);
 366
 367 void drm_mm_remove_node(struct drm_mm_node *node);
 368 void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
 369 void drm_mm_init(struct drm_mm *mm,
 370                  unsigned long start,
 371                  unsigned long size);
 372 void drm_mm_takedown(struct drm_mm *mm);
 373 bool drm_mm_clean(struct drm_mm *mm);
 374
 375 void drm_mm_init_scan(struct drm_mm *mm,
 376                       unsigned long size,
 377                       unsigned alignment,
 378                       unsigned long color);
 379 void drm_mm_init_scan_with_range(struct drm_mm *mm,
 380                                  unsigned long size,
 381                                  unsigned alignment,
 382                                  unsigned long color,
 383                                  unsigned long start,
 384                                  unsigned long end);
 385 bool drm_mm_scan_add_block(struct drm_mm_node *node);
 386 bool drm_mm_scan_remove_block(struct drm_mm_node *node);
 387
 388 void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
 389 #ifdef CONFIG_DEBUG_FS
 390 int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
 391 #endif
 392
 393 #endif