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_next_entry(hole_node, node_list)->start;
 152 }
 153
 154 /**
 155  * drm_mm_hole_node_end - computes the end of the hole following @node
 156  * @hole_node: drm_mm_node which implicitly tracks the following hole
 157  *
 158  * This is useful for driver-sepific debug dumpers. Otherwise drivers should not
 159  * inspect holes themselves. Drivers must check first whether a hole indeed
 160  * follows by looking at node->hole_follows.
 161  *
 162  * Returns:
 163  * End of the subsequent hole.
 164  */
 165 static inline u64 drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 166 {
 167         return __drm_mm_hole_node_end(hole_node);
 168 }
 169
 170 /**
 171  * drm_mm_for_each_node - iterator to walk over all allocated nodes
 172  * @entry: drm_mm_node structure to assign to in each iteration step
 173  * @mm: drm_mm allocator to walk
 174  *
 175  * This iterator walks over all nodes in the range allocator. It is implemented
 176  * with list_for_each, so not save against removal of elements.
 177  */
 178 #define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
 179                                                 &(mm)->head_node.node_list, \
 180                                                 node_list)
 181
 182 #define __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, backwards) \
 183         for (entry = list_entry((backwards) ? (mm)->hole_stack.prev : (mm)->hole_stack.next, struct drm_mm_node, hole_stack); \
 184              &entry->hole_stack != &(mm)->hole_stack ? \
 185              hole_start = drm_mm_hole_node_start(entry), \
 186              hole_end = drm_mm_hole_node_end(entry), \
 187              1 : 0; \
 188              entry = list_entry((backwards) ? entry->hole_stack.prev : entry->hole_stack.next, struct drm_mm_node, hole_stack))
 189
 190 /**
 191  * drm_mm_for_each_hole - iterator to walk over all holes
 192  * @entry: drm_mm_node used internally to track progress
 193  * @mm: drm_mm allocator to walk
 194  * @hole_start: ulong variable to assign the hole start to on each iteration
 195  * @hole_end: ulong variable to assign the hole end to on each iteration
 196  *
 197  * This iterator walks over all holes in the range allocator. It is implemented
 198  * with list_for_each, so not save against removal of elements. @entry is used
 199  * internally and will not reflect a real drm_mm_node for the very first hole.
 200  * Hence users of this iterator may not access it.
 201  *
 202  * Implementation Note:
 203  * We need to inline list_for_each_entry in order to be able to set hole_start
 204  * and hole_end on each iteration while keeping the macro sane.
 205  *
 206  * The __drm_mm_for_each_hole version is similar, but with added support for
 207  * going backwards.
 208  */
 209 #define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
 210         __drm_mm_for_each_hole(entry, mm, hole_start, hole_end, 0)
 211
 212 /*
 213  * Basic range manager support (drm_mm.c)
 214  */
 215 int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
 216
 217 int drm_mm_insert_node_generic(struct drm_mm *mm,
 218                                struct drm_mm_node *node,
 219                                u64 size,
 220                                unsigned alignment,
 221                                unsigned long color,
 222                                enum drm_mm_search_flags sflags,
 223                                enum drm_mm_allocator_flags aflags);
 224 /**
 225  * drm_mm_insert_node - search for space and insert @node
 226  * @mm: drm_mm to allocate from
 227  * @node: preallocate node to insert
 228  * @size: size of the allocation
 229  * @alignment: alignment of the allocation
 230  * @flags: flags to fine-tune the allocation
 231  *
 232  * This is a simplified version of drm_mm_insert_node_generic() with @color set
 233  * to 0.
 234  *
 235  * The preallocated node must be cleared to 0.
 236  *
 237  * Returns:
 238  * 0 on success, -ENOSPC if there's no suitable hole.
 239  */
 240 static inline int drm_mm_insert_node(struct drm_mm *mm,
 241                                      struct drm_mm_node *node,
 242                                      u64 size,
 243                                      unsigned alignment,
 244                                      enum drm_mm_search_flags flags)
 245 {
 246         return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags,
 247                                           DRM_MM_CREATE_DEFAULT);
 248 }
 249
 250 int drm_mm_insert_node_in_range_generic(struct drm_mm *mm,
 251                                         struct drm_mm_node *node,
 252                                         u64 size,
 253                                         unsigned alignment,
 254                                         unsigned long color,
 255                                         u64 start,
 256                                         u64 end,
 257                                         enum drm_mm_search_flags sflags,
 258                                         enum drm_mm_allocator_flags aflags);
 259 /**
 260  * drm_mm_insert_node_in_range - ranged search for space and insert @node
 261  * @mm: drm_mm to allocate from
 262  * @node: preallocate node to insert
 263  * @size: size of the allocation
 264  * @alignment: alignment of the allocation
 265  * @start: start of the allowed range for this node
 266  * @end: end of the allowed range for this node
 267  * @flags: flags to fine-tune the allocation
 268  *
 269  * This is a simplified version of drm_mm_insert_node_in_range_generic() with
 270  * @color set to 0.
 271  *
 272  * The preallocated node must be cleared to 0.
 273  *
 274  * Returns:
 275  * 0 on success, -ENOSPC if there's no suitable hole.
 276  */
 277 static inline int drm_mm_insert_node_in_range(struct drm_mm *mm,
 278                                               struct drm_mm_node *node,
 279                                               u64 size,
 280                                               unsigned alignment,
 281                                               u64 start,
 282                                               u64 end,
 283                                               enum drm_mm_search_flags flags)
 284 {
 285         return drm_mm_insert_node_in_range_generic(mm, node, size, alignment,
 286                                                    0, start, end, flags,
 287                                                    DRM_MM_CREATE_DEFAULT);
 288 }
 289
 290 void drm_mm_remove_node(struct drm_mm_node *node);
 291 void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
 292 void drm_mm_init(struct drm_mm *mm,
 293                  u64 start,
 294                  u64 size);
 295 void drm_mm_takedown(struct drm_mm *mm);
 296 bool drm_mm_clean(struct drm_mm *mm);
 297
 298 void drm_mm_init_scan(struct drm_mm *mm,
 299                       u64 size,
 300                       unsigned alignment,
 301                       unsigned long color);
 302 void drm_mm_init_scan_with_range(struct drm_mm *mm,
 303                                  u64 size,
 304                                  unsigned alignment,
 305                                  unsigned long color,
 306                                  u64 start,
 307                                  u64 end);
 308 bool drm_mm_scan_add_block(struct drm_mm_node *node);
 309 bool drm_mm_scan_remove_block(struct drm_mm_node *node);
 310
 311 void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
 312 #ifdef CONFIG_DEBUG_FS
 313 int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);
 314 #endif
 315
 316 #endif