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1/**************************************************************************2 *3 * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. USA.4 * Copyright 2016 Intel Corporation5 * All Rights Reserved.6 *7 * Permission is hereby granted, free of charge, to any person obtaining a8 * copy of this software and associated documentation files (the9 * "Software"), to deal in the Software without restriction, including10 * without limitation the rights to use, copy, modify, merge, publish,11 * distribute, sub license, and/or sell copies of the Software, and to12 * permit persons to whom the Software is furnished to do so, subject to13 * the following conditions:14 *15 * The above copyright notice and this permission notice (including the16 * next paragraph) shall be included in all copies or substantial portions17 * of the Software.18 *19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE25 * USE OR OTHER DEALINGS IN THE SOFTWARE.26 *27 *28 **************************************************************************/29/*30 * Authors:31 * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>32 */33 34#ifndef _DRM_MM_H_35#define _DRM_MM_H_36 37/*38 * Generic range manager structs39 */40#include <linux/bug.h>41#include <linux/rbtree.h>42#include <linux/limits.h>43#include <linux/mm_types.h>44#include <linux/list.h>45#include <linux/spinlock.h>46#ifdef CONFIG_DRM_DEBUG_MM47#include <linux/stackdepot.h>48#endif49#include <linux/types.h>50 51#include <drm/drm_print.h>52 53#ifdef CONFIG_DRM_DEBUG_MM54#define DRM_MM_BUG_ON(expr) BUG_ON(expr)55#else56#define DRM_MM_BUG_ON(expr) BUILD_BUG_ON_INVALID(expr)57#endif58 59/**60 * enum drm_mm_insert_mode - control search and allocation behaviour61 *62 * The &struct drm_mm range manager supports finding a suitable modes using63 * a number of search trees. These trees are oranised by size, by address and64 * in most recent eviction order. This allows the user to find either the65 * smallest hole to reuse, the lowest or highest address to reuse, or simply66 * reuse the most recent eviction that fits. When allocating the &drm_mm_node67 * from within the hole, the &drm_mm_insert_mode also dictate whether to68 * allocate the lowest matching address or the highest.69 */70enum drm_mm_insert_mode {71 /**72 * @DRM_MM_INSERT_BEST:73 *74 * Search for the smallest hole (within the search range) that fits75 * the desired node.76 *77 * Allocates the node from the bottom of the found hole.78 */79 DRM_MM_INSERT_BEST = 0,80 81 /**82 * @DRM_MM_INSERT_LOW:83 *84 * Search for the lowest hole (address closest to 0, within the search85 * range) that fits the desired node.86 *87 * Allocates the node from the bottom of the found hole.88 */89 DRM_MM_INSERT_LOW,90 91 /**92 * @DRM_MM_INSERT_HIGH:93 *94 * Search for the highest hole (address closest to U64_MAX, within the95 * search range) that fits the desired node.96 *97 * Allocates the node from the *top* of the found hole. The specified98 * alignment for the node is applied to the base of the node99 * (&drm_mm_node.start).100 */101 DRM_MM_INSERT_HIGH,102 103 /**104 * @DRM_MM_INSERT_EVICT:105 *106 * Search for the most recently evicted hole (within the search range)107 * that fits the desired node. This is appropriate for use immediately108 * after performing an eviction scan (see drm_mm_scan_init()) and109 * removing the selected nodes to form a hole.110 *111 * Allocates the node from the bottom of the found hole.112 */113 DRM_MM_INSERT_EVICT,114 115 /**116 * @DRM_MM_INSERT_ONCE:117 *118 * Only check the first hole for suitablity and report -ENOSPC119 * immediately otherwise, rather than check every hole until a120 * suitable one is found. Can only be used in conjunction with another121 * search method such as DRM_MM_INSERT_HIGH or DRM_MM_INSERT_LOW.122 */123 DRM_MM_INSERT_ONCE = BIT(31),124 125 /**126 * @DRM_MM_INSERT_HIGHEST:127 *128 * Only check the highest hole (the hole with the largest address) and129 * insert the node at the top of the hole or report -ENOSPC if130 * unsuitable.131 *132 * Does not search all holes.133 */134 DRM_MM_INSERT_HIGHEST = DRM_MM_INSERT_HIGH | DRM_MM_INSERT_ONCE,135 136 /**137 * @DRM_MM_INSERT_LOWEST:138 *139 * Only check the lowest hole (the hole with the smallest address) and140 * insert the node at the bottom of the hole or report -ENOSPC if141 * unsuitable.142 *143 * Does not search all holes.144 */145 DRM_MM_INSERT_LOWEST = DRM_MM_INSERT_LOW | DRM_MM_INSERT_ONCE,146};147 148/**149 * struct drm_mm_node - allocated block in the DRM allocator150 *151 * This represents an allocated block in a &drm_mm allocator. Except for152 * pre-reserved nodes inserted using drm_mm_reserve_node() the structure is153 * entirely opaque and should only be accessed through the provided funcions.154 * Since allocation of these nodes is entirely handled by the driver they can be155 * embedded.156 */157struct drm_mm_node {158 /** @color: Opaque driver-private tag. */159 unsigned long color;160 /** @start: Start address of the allocated block. */161 u64 start;162 /** @size: Size of the allocated block. */163 u64 size;164 /* private: */165 struct drm_mm *mm;166 struct list_head node_list;167 struct list_head hole_stack;168 struct rb_node rb;169 struct rb_node rb_hole_size;170 struct rb_node rb_hole_addr;171 u64 __subtree_last;172 u64 hole_size;173 u64 subtree_max_hole;174 unsigned long flags;175#define DRM_MM_NODE_ALLOCATED_BIT 0176#define DRM_MM_NODE_SCANNED_BIT 1177#ifdef CONFIG_DRM_DEBUG_MM178 depot_stack_handle_t stack;179#endif180};181 182/**183 * struct drm_mm - DRM allocator184 *185 * DRM range allocator with a few special functions and features geared towards186 * managing GPU memory. Except for the @color_adjust callback the structure is187 * entirely opaque and should only be accessed through the provided functions188 * and macros. This structure can be embedded into larger driver structures.189 */190struct drm_mm {191 /**192 * @color_adjust:193 *194 * Optional driver callback to further apply restrictions on a hole. The195 * node argument points at the node containing the hole from which the196 * block would be allocated (see drm_mm_hole_follows() and friends). The197 * other arguments are the size of the block to be allocated. The driver198 * can adjust the start and end as needed to e.g. insert guard pages.199 */200 void (*color_adjust)(const struct drm_mm_node *node,201 unsigned long color,202 u64 *start, u64 *end);203 204 /* private: */205 /* List of all memory nodes that immediately precede a free hole. */206 struct list_head hole_stack;207 /* head_node.node_list is the list of all memory nodes, ordered208 * according to the (increasing) start address of the memory node. */209 struct drm_mm_node head_node;210 /* Keep an interval_tree for fast lookup of drm_mm_nodes by address. */211 struct rb_root_cached interval_tree;212 struct rb_root_cached holes_size;213 struct rb_root holes_addr;214 215 unsigned long scan_active;216};217 218/**219 * struct drm_mm_scan - DRM allocator eviction roaster data220 *221 * This structure tracks data needed for the eviction roaster set up using222 * drm_mm_scan_init(), and used with drm_mm_scan_add_block() and223 * drm_mm_scan_remove_block(). The structure is entirely opaque and should only224 * be accessed through the provided functions and macros. It is meant to be225 * allocated temporarily by the driver on the stack.226 */227struct drm_mm_scan {228 /* private: */229 struct drm_mm *mm;230 231 u64 size;232 u64 alignment;233 u64 remainder_mask;234 235 u64 range_start;236 u64 range_end;237 238 u64 hit_start;239 u64 hit_end;240 241 unsigned long color;242 enum drm_mm_insert_mode mode;243};244 245/**246 * drm_mm_node_allocated - checks whether a node is allocated247 * @node: drm_mm_node to check248 *249 * Drivers are required to clear a node prior to using it with the250 * drm_mm range manager.251 *252 * Drivers should use this helper for proper encapsulation of drm_mm253 * internals.254 *255 * Returns:256 * True if the @node is allocated.257 */258static inline bool drm_mm_node_allocated(const struct drm_mm_node *node)259{260 return test_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags);261}262 263/**264 * drm_mm_initialized - checks whether an allocator is initialized265 * @mm: drm_mm to check266 *267 * Drivers should clear the struct drm_mm prior to initialisation if they268 * want to use this function.269 *270 * Drivers should use this helper for proper encapsulation of drm_mm271 * internals.272 *273 * Returns:274 * True if the @mm is initialized.275 */276static inline bool drm_mm_initialized(const struct drm_mm *mm)277{278 return READ_ONCE(mm->hole_stack.next);279}280 281/**282 * drm_mm_hole_follows - checks whether a hole follows this node283 * @node: drm_mm_node to check284 *285 * Holes are embedded into the drm_mm using the tail of a drm_mm_node.286 * If you wish to know whether a hole follows this particular node,287 * query this function. See also drm_mm_hole_node_start() and288 * drm_mm_hole_node_end().289 *290 * Returns:291 * True if a hole follows the @node.292 */293static inline bool drm_mm_hole_follows(const struct drm_mm_node *node)294{295 return node->hole_size;296}297 298static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node)299{300 return hole_node->start + hole_node->size;301}302 303/**304 * drm_mm_hole_node_start - computes the start of the hole following @node305 * @hole_node: drm_mm_node which implicitly tracks the following hole306 *307 * This is useful for driver-specific debug dumpers. Otherwise drivers should308 * not inspect holes themselves. Drivers must check first whether a hole indeed309 * follows by looking at drm_mm_hole_follows()310 *311 * Returns:312 * Start of the subsequent hole.313 */314static inline u64 drm_mm_hole_node_start(const struct drm_mm_node *hole_node)315{316 DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node));317 return __drm_mm_hole_node_start(hole_node);318}319 320static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node)321{322 return list_next_entry(hole_node, node_list)->start;323}324 325/**326 * drm_mm_hole_node_end - computes the end of the hole following @node327 * @hole_node: drm_mm_node which implicitly tracks the following hole328 *329 * This is useful for driver-specific debug dumpers. Otherwise drivers should330 * not inspect holes themselves. Drivers must check first whether a hole indeed331 * follows by looking at drm_mm_hole_follows().332 *333 * Returns:334 * End of the subsequent hole.335 */336static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node)337{338 return __drm_mm_hole_node_end(hole_node);339}340 341/**342 * drm_mm_nodes - list of nodes under the drm_mm range manager343 * @mm: the struct drm_mm range manager344 *345 * As the drm_mm range manager hides its node_list deep with its346 * structure, extracting it looks painful and repetitive. This is347 * not expected to be used outside of the drm_mm_for_each_node()348 * macros and similar internal functions.349 *350 * Returns:351 * The node list, may be empty.352 */353#define drm_mm_nodes(mm) (&(mm)->head_node.node_list)354 355/**356 * drm_mm_for_each_node - iterator to walk over all allocated nodes357 * @entry: &struct drm_mm_node to assign to in each iteration step358 * @mm: &drm_mm allocator to walk359 *360 * This iterator walks over all nodes in the range allocator. It is implemented361 * with list_for_each(), so not save against removal of elements.362 */363#define drm_mm_for_each_node(entry, mm) \364 list_for_each_entry(entry, drm_mm_nodes(mm), node_list)365 366/**367 * drm_mm_for_each_node_safe - iterator to walk over all allocated nodes368 * @entry: &struct drm_mm_node to assign to in each iteration step369 * @next: &struct drm_mm_node to store the next step370 * @mm: &drm_mm allocator to walk371 *372 * This iterator walks over all nodes in the range allocator. It is implemented373 * with list_for_each_safe(), so save against removal of elements.374 */375#define drm_mm_for_each_node_safe(entry, next, mm) \376 list_for_each_entry_safe(entry, next, drm_mm_nodes(mm), node_list)377 378/**379 * drm_mm_for_each_hole - iterator to walk over all holes380 * @pos: &drm_mm_node used internally to track progress381 * @mm: &drm_mm allocator to walk382 * @hole_start: ulong variable to assign the hole start to on each iteration383 * @hole_end: ulong variable to assign the hole end to on each iteration384 *385 * This iterator walks over all holes in the range allocator. It is implemented386 * with list_for_each(), so not save against removal of elements. @entry is used387 * internally and will not reflect a real drm_mm_node for the very first hole.388 * Hence users of this iterator may not access it.389 *390 * Implementation Note:391 * We need to inline list_for_each_entry in order to be able to set hole_start392 * and hole_end on each iteration while keeping the macro sane.393 */394#define drm_mm_for_each_hole(pos, mm, hole_start, hole_end) \395 for (pos = list_first_entry(&(mm)->hole_stack, \396 typeof(*pos), hole_stack); \397 &pos->hole_stack != &(mm)->hole_stack ? \398 hole_start = drm_mm_hole_node_start(pos), \399 hole_end = hole_start + pos->hole_size, \400 1 : 0; \401 pos = list_next_entry(pos, hole_stack))402 403/*404 * Basic range manager support (drm_mm.c)405 */406int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);407int drm_mm_insert_node_in_range(struct drm_mm *mm,408 struct drm_mm_node *node,409 u64 size,410 u64 alignment,411 unsigned long color,412 u64 start,413 u64 end,414 enum drm_mm_insert_mode mode);415 416/**417 * drm_mm_insert_node_generic - search for space and insert @node418 * @mm: drm_mm to allocate from419 * @node: preallocate node to insert420 * @size: size of the allocation421 * @alignment: alignment of the allocation422 * @color: opaque tag value to use for this node423 * @mode: fine-tune the allocation search and placement424 *425 * This is a simplified version of drm_mm_insert_node_in_range() with no426 * range restrictions applied.427 *428 * The preallocated node must be cleared to 0.429 *430 * Returns:431 * 0 on success, -ENOSPC if there's no suitable hole.432 */433static inline int434drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node,435 u64 size, u64 alignment,436 unsigned long color,437 enum drm_mm_insert_mode mode)438{439 return drm_mm_insert_node_in_range(mm, node,440 size, alignment, color,441 0, U64_MAX, mode);442}443 444/**445 * drm_mm_insert_node - search for space and insert @node446 * @mm: drm_mm to allocate from447 * @node: preallocate node to insert448 * @size: size of the allocation449 *450 * This is a simplified version of drm_mm_insert_node_generic() with @color set451 * to 0.452 *453 * The preallocated node must be cleared to 0.454 *455 * Returns:456 * 0 on success, -ENOSPC if there's no suitable hole.457 */458static inline int drm_mm_insert_node(struct drm_mm *mm,459 struct drm_mm_node *node,460 u64 size)461{462 return drm_mm_insert_node_generic(mm, node, size, 0, 0, 0);463}464 465void drm_mm_remove_node(struct drm_mm_node *node);466void drm_mm_init(struct drm_mm *mm, u64 start, u64 size);467void drm_mm_takedown(struct drm_mm *mm);468 469/**470 * drm_mm_clean - checks whether an allocator is clean471 * @mm: drm_mm allocator to check472 *473 * Returns:474 * True if the allocator is completely free, false if there's still a node475 * allocated in it.476 */477static inline bool drm_mm_clean(const struct drm_mm *mm)478{479 return list_empty(drm_mm_nodes(mm));480}481 482struct drm_mm_node *483__drm_mm_interval_first(const struct drm_mm *mm, u64 start, u64 last);484 485/**486 * drm_mm_for_each_node_in_range - iterator to walk over a range of487 * allocated nodes488 * @node__: drm_mm_node structure to assign to in each iteration step489 * @mm__: drm_mm allocator to walk490 * @start__: starting offset, the first node will overlap this491 * @end__: ending offset, the last node will start before this (but may overlap)492 *493 * This iterator walks over all nodes in the range allocator that lie494 * between @start and @end. It is implemented similarly to list_for_each(),495 * but using the internal interval tree to accelerate the search for the496 * starting node, and so not safe against removal of elements. It assumes497 * that @end is within (or is the upper limit of) the drm_mm allocator.498 * If [@start, @end] are beyond the range of the drm_mm, the iterator may walk499 * over the special _unallocated_ &drm_mm.head_node, and may even continue500 * indefinitely.501 */502#define drm_mm_for_each_node_in_range(node__, mm__, start__, end__) \503 for (node__ = __drm_mm_interval_first((mm__), (start__), (end__)-1); \504 node__->start < (end__); \505 node__ = list_next_entry(node__, node_list))506 507void drm_mm_scan_init_with_range(struct drm_mm_scan *scan,508 struct drm_mm *mm,509 u64 size, u64 alignment, unsigned long color,510 u64 start, u64 end,511 enum drm_mm_insert_mode mode);512 513/**514 * drm_mm_scan_init - initialize lru scanning515 * @scan: scan state516 * @mm: drm_mm to scan517 * @size: size of the allocation518 * @alignment: alignment of the allocation519 * @color: opaque tag value to use for the allocation520 * @mode: fine-tune the allocation search and placement521 *522 * This is a simplified version of drm_mm_scan_init_with_range() with no range523 * restrictions applied.524 *525 * This simply sets up the scanning routines with the parameters for the desired526 * hole.527 *528 * Warning:529 * As long as the scan list is non-empty, no other operations than530 * adding/removing nodes to/from the scan list are allowed.531 */532static inline void drm_mm_scan_init(struct drm_mm_scan *scan,533 struct drm_mm *mm,534 u64 size,535 u64 alignment,536 unsigned long color,537 enum drm_mm_insert_mode mode)538{539 drm_mm_scan_init_with_range(scan, mm,540 size, alignment, color,541 0, U64_MAX, mode);542}543 544bool drm_mm_scan_add_block(struct drm_mm_scan *scan,545 struct drm_mm_node *node);546bool drm_mm_scan_remove_block(struct drm_mm_scan *scan,547 struct drm_mm_node *node);548struct drm_mm_node *drm_mm_scan_color_evict(struct drm_mm_scan *scan);549 550void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p);551 552#endif553