/************************************************************************** * * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE * USE OR OTHER DEALINGS IN THE SOFTWARE. * * **************************************************************************/ /* * Generic simple memory manager implementation. Intended to be used as a base * class implementation for more advanced memory managers. * * Note that the algorithm used is quite simple and there might be substantial * performance gains if a smarter free list is implemented. Currently it is just an * unordered stack of free regions. This could easily be improved if an RB-tree * is used instead. At least if we expect heavy fragmentation. * * Aligned allocations can also see improvement. * * Authors: * Thomas Hellström <thomas-at-tungstengraphics-dot-com> */ #include <drm/drmP.h> #include <drm/drm_mm.h> #include <linux/slab.h> #include <linux/seq_file.h> #include <linux/export.h> #define MM_UNUSED_TARGET 4 static struct drm_mm_node *drm_mm_kmalloc(struct drm_mm *mm, int atomic) { struct drm_mm_node *child; if (atomic) child = kzalloc(sizeof(*child), GFP_ATOMIC); else child = kzalloc(sizeof(*child), GFP_KERNEL); if (unlikely(child == NULL)) { spin_lock(&mm->unused_lock); if (list_empty(&mm->unused_nodes)) child = NULL; else { child = list_entry(mm->unused_nodes.next, struct drm_mm_node, node_list); list_del(&child->node_list); --mm->num_unused; } spin_unlock(&mm->unused_lock); } return child; } /* drm_mm_pre_get() - pre allocate drm_mm_node structure * drm_mm: memory manager struct we are pre-allocating for * * Returns 0 on success or -ENOMEM if allocation fails. */ int drm_mm_pre_get(struct drm_mm *mm) { struct drm_mm_node *node; spin_lock(&mm->unused_lock); while (mm->num_unused < MM_UNUSED_TARGET) { spin_unlock(&mm->unused_lock); node = kzalloc(sizeof(*node), GFP_KERNEL); spin_lock(&mm->unused_lock); if (unlikely(node == NULL)) { int ret = (mm->num_unused < 2) ? -ENOMEM : 0; spin_unlock(&mm->unused_lock); return ret; } ++mm->num_unused; list_add_tail(&node->node_list, &mm->unused_nodes); } spin_unlock(&mm->unused_lock); return 0; } EXPORT_SYMBOL(drm_mm_pre_get); static void drm_mm_insert_helper(struct drm_mm_node *hole_node, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long color) { struct drm_mm *mm = hole_node->mm; unsigned long hole_start = drm_mm_hole_node_start(hole_node); unsigned long hole_end = drm_mm_hole_node_end(hole_node); unsigned long adj_start = hole_start; unsigned long adj_end = hole_end; BUG_ON(node->allocated); if (mm->color_adjust) mm->color_adjust(hole_node, color, &adj_start, &adj_end); if (alignment) { unsigned tmp = adj_start % alignment; if (tmp) adj_start += alignment - tmp; } if (adj_start == hole_start) { hole_node->hole_follows = 0; list_del(&hole_node->hole_stack); } node->start = adj_start; node->size = size; node->mm = mm; node->color = color; node->allocated = 1; INIT_LIST_HEAD(&node->hole_stack); list_add(&node->node_list, &hole_node->node_list); BUG_ON(node->start + node->size > adj_end); node->hole_follows = 0; if (__drm_mm_hole_node_start(node) < hole_end) { list_add(&node->hole_stack, &mm->hole_stack); node->hole_follows = 1; } } struct drm_mm_node *drm_mm_create_block(struct drm_mm *mm, unsigned long start, unsigned long size, bool atomic) { struct drm_mm_node *hole, *node; unsigned long end = start + size; unsigned long hole_start; unsigned long hole_end; drm_mm_for_each_hole(hole, mm, hole_start, hole_end) { if (hole_start > start || hole_end < end) continue; node = drm_mm_kmalloc(mm, atomic); if (unlikely(node == NULL)) return NULL; node->start = start; node->size = size; node->mm = mm; node->allocated = 1; INIT_LIST_HEAD(&node->hole_stack); list_add(&node->node_list, &hole->node_list); if (start == hole_start) { hole->hole_follows = 0; list_del_init(&hole->hole_stack); } node->hole_follows = 0; if (end != hole_end) { list_add(&node->hole_stack, &mm->hole_stack); node->hole_follows = 1; } return node; } WARN(1, "no hole found for block 0x%lx + 0x%lx\n", start, size); return NULL; } EXPORT_SYMBOL(drm_mm_create_block); struct drm_mm_node *drm_mm_get_block_generic(struct drm_mm_node *hole_node, unsigned long size, unsigned alignment, unsigned long color, int atomic) { struct drm_mm_node *node; node = drm_mm_kmalloc(hole_node->mm, atomic); if (unlikely(node == NULL)) return NULL; drm_mm_insert_helper(hole_node, node, size, alignment, color); return node; } EXPORT_SYMBOL(drm_mm_get_block_generic); /** * Search for free space and insert a preallocated memory node. Returns * -ENOSPC if no suitable free area is available. The preallocated memory node * must be cleared. */ int drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long color) { struct drm_mm_node *hole_node; hole_node = drm_mm_search_free_generic(mm, size, alignment, color, 0); if (!hole_node) return -ENOSPC; drm_mm_insert_helper(hole_node, node, size, alignment, color); return 0; } EXPORT_SYMBOL(drm_mm_insert_node_generic); int drm_mm_insert_node(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment) { return drm_mm_insert_node_generic(mm, node, size, alignment, 0); } EXPORT_SYMBOL(drm_mm_insert_node); static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long color, unsigned long start, unsigned long end) { struct drm_mm *mm = hole_node->mm; unsigned long hole_start = drm_mm_hole_node_start(hole_node); unsigned long hole_end = drm_mm_hole_node_end(hole_node); unsigned long adj_start = hole_start; unsigned long adj_end = hole_end; BUG_ON(!hole_node->hole_follows || node->allocated); if (adj_start < start) adj_start = start; if (adj_end > end) adj_end = end; if (mm->color_adjust) mm->color_adjust(hole_node, color, &adj_start, &adj_end); if (alignment) { unsigned tmp = adj_start % alignment; if (tmp) adj_start += alignment - tmp; } if (adj_start == hole_start) { hole_node->hole_follows = 0; list_del(&hole_node->hole_stack); } node->start = adj_start; node->size = size; node->mm = mm; node->color = color; node->allocated = 1; INIT_LIST_HEAD(&node->hole_stack); list_add(&node->node_list, &hole_node->node_list); BUG_ON(node->start + node->size > adj_end); BUG_ON(node->start + node->size > end); node->hole_follows = 0; if (__drm_mm_hole_node_start(node) < hole_end) { list_add(&node->hole_stack, &mm->hole_stack); node->hole_follows = 1; } } struct drm_mm_node *drm_mm_get_block_range_generic(struct drm_mm_node *hole_node, unsigned long size, unsigned alignment, unsigned long color, unsigned long start, unsigned long end, int atomic) { struct drm_mm_node *node; node = drm_mm_kmalloc(hole_node->mm, atomic); if (unlikely(node == NULL)) return NULL; drm_mm_insert_helper_range(hole_node, node, size, alignment, color, start, end); return node; } EXPORT_SYMBOL(drm_mm_get_block_range_generic); /** * Search for free space and insert a preallocated memory node. Returns * -ENOSPC if no suitable free area is available. This is for range * restricted allocations. The preallocated memory node must be cleared. */ int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long color, unsigned long start, unsigned long end) { struct drm_mm_node *hole_node; hole_node = drm_mm_search_free_in_range_generic(mm, size, alignment, color, start, end, 0); if (!hole_node) return -ENOSPC; drm_mm_insert_helper_range(hole_node, node, size, alignment, color, start, end); return 0; } EXPORT_SYMBOL(drm_mm_insert_node_in_range_generic); int drm_mm_insert_node_in_range(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long start, unsigned long end) { return drm_mm_insert_node_in_range_generic(mm, node, size, alignment, 0, start, end); } EXPORT_SYMBOL(drm_mm_insert_node_in_range); /** * Remove a memory node from the allocator. */ void drm_mm_remove_node(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; BUG_ON(node->scanned_block || node->scanned_prev_free || node->scanned_next_free); prev_node = list_entry(node->node_list.prev, struct drm_mm_node, node_list); if (node->hole_follows) { BUG_ON(__drm_mm_hole_node_start(node) == __drm_mm_hole_node_end(node)); list_del(&node->hole_stack); } else BUG_ON(__drm_mm_hole_node_start(node) != __drm_mm_hole_node_end(node)); if (!prev_node->hole_follows) { prev_node->hole_follows = 1; list_add(&prev_node->hole_stack, &mm->hole_stack); } else list_move(&prev_node->hole_stack, &mm->hole_stack); list_del(&node->node_list); node->allocated = 0; } EXPORT_SYMBOL(drm_mm_remove_node); /* * Remove a memory node from the allocator and free the allocated struct * drm_mm_node. Only to be used on a struct drm_mm_node obtained by one of the * drm_mm_get_block functions. */ void drm_mm_put_block(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; drm_mm_remove_node(node); spin_lock(&mm->unused_lock); if (mm->num_unused < MM_UNUSED_TARGET) { list_add(&node->node_list, &mm->unused_nodes); ++mm->num_unused; } else kfree(node); spin_unlock(&mm->unused_lock); } EXPORT_SYMBOL(drm_mm_put_block); static int check_free_hole(unsigned long start, unsigned long end, unsigned long size, unsigned alignment) { if (end - start < size) return 0; if (alignment) { unsigned tmp = start % alignment; if (tmp) start += alignment - tmp; } return end >= start + size; } struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm, unsigned long size, unsigned alignment, unsigned long color, bool best_match) { struct drm_mm_node *entry; struct drm_mm_node *best; unsigned long adj_start; unsigned long adj_end; unsigned long best_size; BUG_ON(mm->scanned_blocks); best = NULL; best_size = ~0UL; drm_mm_for_each_hole(entry, mm, adj_start, adj_end) { if (mm->color_adjust) { mm->color_adjust(entry, color, &adj_start, &adj_end); if (adj_end <= adj_start) continue; } if (!check_free_hole(adj_start, adj_end, size, alignment)) continue; if (!best_match) return entry; if (entry->size < best_size) { best = entry; best_size = entry->size; } } return best; } EXPORT_SYMBOL(drm_mm_search_free_generic); struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm, unsigned long size, unsigned alignment, unsigned long color, unsigned long start, unsigned long end, bool best_match) { struct drm_mm_node *entry; struct drm_mm_node *best; unsigned long adj_start; unsigned long adj_end; unsigned long best_size; BUG_ON(mm->scanned_blocks); best = NULL; best_size = ~0UL; drm_mm_for_each_hole(entry, mm, adj_start, adj_end) { if (adj_start < start) adj_start = start; if (adj_end > end) adj_end = end; if (mm->color_adjust) { mm->color_adjust(entry, color, &adj_start, &adj_end); if (adj_end <= adj_start) continue; } if (!check_free_hole(adj_start, adj_end, size, alignment)) continue; if (!best_match) return entry; if (entry->size < best_size) { best = entry; best_size = entry->size; } } return best; } EXPORT_SYMBOL(drm_mm_search_free_in_range_generic); /** * Moves an allocation. To be used with embedded struct drm_mm_node. */ void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new) { list_replace(&old->node_list, &new->node_list); list_replace(&old->hole_stack, &new->hole_stack); new->hole_follows = old->hole_follows; new->mm = old->mm; new->start = old->start; new->size = old->size; new->color = old->color; old->allocated = 0; new->allocated = 1; } EXPORT_SYMBOL(drm_mm_replace_node); /** * Initializa lru scanning. * * This simply sets up the scanning routines with the parameters for the desired * hole. * * Warning: As long as the scan list is non-empty, no other operations than * adding/removing nodes to/from the scan list are allowed. */ void drm_mm_init_scan(struct drm_mm *mm, unsigned long size, unsigned alignment, unsigned long color) { mm->scan_color = color; mm->scan_alignment = alignment; mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; mm->scan_hit_end = 0; mm->scan_check_range = 0; mm->prev_scanned_node = NULL; } EXPORT_SYMBOL(drm_mm_init_scan); /** * Initializa lru scanning. * * This simply sets up the scanning routines with the parameters for the desired * hole. This version is for range-restricted scans. * * Warning: As long as the scan list is non-empty, no other operations than * adding/removing nodes to/from the scan list are allowed. */ void drm_mm_init_scan_with_range(struct drm_mm *mm, unsigned long size, unsigned alignment, unsigned long color, unsigned long start, unsigned long end) { mm->scan_color = color; mm->scan_alignment = alignment; mm->scan_size = size; mm->scanned_blocks = 0; mm->scan_hit_start = 0; mm->scan_hit_end = 0; mm->scan_start = start; mm->scan_end = end; mm->scan_check_range = 1; mm->prev_scanned_node = NULL; } EXPORT_SYMBOL(drm_mm_init_scan_with_range); /** * Add a node to the scan list that might be freed to make space for the desired * hole. * * Returns non-zero, if a hole has been found, zero otherwise. */ int drm_mm_scan_add_block(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; unsigned long hole_start, hole_end; unsigned long adj_start, adj_end; mm->scanned_blocks++; BUG_ON(node->scanned_block); node->scanned_block = 1; prev_node = list_entry(node->node_list.prev, struct drm_mm_node, node_list); node->scanned_preceeds_hole = prev_node->hole_follows; prev_node->hole_follows = 1; list_del(&node->node_list); node->node_list.prev = &prev_node->node_list; node->node_list.next = &mm->prev_scanned_node->node_list; mm->prev_scanned_node = node; adj_start = hole_start = drm_mm_hole_node_start(prev_node); adj_end = hole_end = drm_mm_hole_node_end(prev_node); if (mm->scan_check_range) { if (adj_start < mm->scan_start) adj_start = mm->scan_start; if (adj_end > mm->scan_end) adj_end = mm->scan_end; } if (mm->color_adjust) mm->color_adjust(prev_node, mm->scan_color, &adj_start, &adj_end); if (check_free_hole(adj_start, adj_end, mm->scan_size, mm->scan_alignment)) { mm->scan_hit_start = hole_start; mm->scan_hit_end = hole_end; return 1; } return 0; } EXPORT_SYMBOL(drm_mm_scan_add_block); /** * Remove a node from the scan list. * * Nodes _must_ be removed in the exact same order from the scan list as they * have been added, otherwise the internal state of the memory manager will be * corrupted. * * When the scan list is empty, the selected memory nodes can be freed. An * immediately following drm_mm_search_free with best_match = 0 will then return * the just freed block (because its at the top of the free_stack list). * * Returns one if this block should be evicted, zero otherwise. Will always * return zero when no hole has been found. */ int drm_mm_scan_remove_block(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; mm->scanned_blocks--; BUG_ON(!node->scanned_block); node->scanned_block = 0; prev_node = list_entry(node->node_list.prev, struct drm_mm_node, node_list); prev_node->hole_follows = node->scanned_preceeds_hole; list_add(&node->node_list, &prev_node->node_list); return (drm_mm_hole_node_end(node) > mm->scan_hit_start && node->start < mm->scan_hit_end); } EXPORT_SYMBOL(drm_mm_scan_remove_block); int drm_mm_clean(struct drm_mm * mm) { struct list_head *head = &mm->head_node.node_list; return (head->next->next == head); } EXPORT_SYMBOL(drm_mm_clean); int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size) { INIT_LIST_HEAD(&mm->hole_stack); INIT_LIST_HEAD(&mm->unused_nodes); mm->num_unused = 0; mm->scanned_blocks = 0; spin_lock_init(&mm->unused_lock); /* Clever trick to avoid a special case in the free hole tracking. */ INIT_LIST_HEAD(&mm->head_node.node_list); INIT_LIST_HEAD(&mm->head_node.hole_stack); mm->head_node.hole_follows = 1; mm->head_node.scanned_block = 0; mm->head_node.scanned_prev_free = 0; mm->head_node.scanned_next_free = 0; mm->head_node.mm = mm; mm->head_node.start = start + size; mm->head_node.size = start - mm->head_node.start; list_add_tail(&mm->head_node.hole_stack, &mm->hole_stack); mm->color_adjust = NULL; return 0; } EXPORT_SYMBOL(drm_mm_init); void drm_mm_takedown(struct drm_mm * mm) { struct drm_mm_node *entry, *next; if (!list_empty(&mm->head_node.node_list)) { DRM_ERROR("Memory manager not clean. Delaying takedown\n"); return; } spin_lock(&mm->unused_lock); list_for_each_entry_safe(entry, next, &mm->unused_nodes, node_list) { list_del(&entry->node_list); kfree(entry); --mm->num_unused; } spin_unlock(&mm->unused_lock); BUG_ON(mm->num_unused != 0); } EXPORT_SYMBOL(drm_mm_takedown); void drm_mm_debug_table(struct drm_mm *mm, const char *prefix) { struct drm_mm_node *entry; unsigned long total_used = 0, total_free = 0, total = 0; unsigned long hole_start, hole_end, hole_size; hole_start = drm_mm_hole_node_start(&mm->head_node); hole_end = drm_mm_hole_node_end(&mm->head_node); hole_size = hole_end - hole_start; if (hole_size) printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: free\n", prefix, hole_start, hole_end, hole_size); total_free += hole_size; drm_mm_for_each_node(entry, mm) { printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: used\n", prefix, entry->start, entry->start + entry->size, entry->size); total_used += entry->size; if (entry->hole_follows) { hole_start = drm_mm_hole_node_start(entry); hole_end = drm_mm_hole_node_end(entry); hole_size = hole_end - hole_start; printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: free\n", prefix, hole_start, hole_end, hole_size); total_free += hole_size; } } total = total_free + total_used; printk(KERN_DEBUG "%s total: %lu, used %lu free %lu\n", prefix, total, total_used, total_free); } EXPORT_SYMBOL(drm_mm_debug_table); #if defined(CONFIG_DEBUG_FS) static unsigned long drm_mm_dump_hole(struct seq_file *m, struct drm_mm_node *entry) { unsigned long hole_start, hole_end, hole_size; if (entry->hole_follows) { hole_start = drm_mm_hole_node_start(entry); hole_end = drm_mm_hole_node_end(entry); hole_size = hole_end - hole_start; seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: free\n", hole_start, hole_end, hole_size); return hole_size; } return 0; } int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm) { struct drm_mm_node *entry; unsigned long total_used = 0, total_free = 0, total = 0; total_free += drm_mm_dump_hole(m, &mm->head_node); drm_mm_for_each_node(entry, mm) { seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: used\n", entry->start, entry->start + entry->size, entry->size); total_used += entry->size; total_free += drm_mm_dump_hole(m, entry); } total = total_free + total_used; seq_printf(m, "total: %lu, used %lu free %lu\n", total, total_used, total_free); return 0; } EXPORT_SYMBOL(drm_mm_dump_table); #endif