934 lines
27 KiB
C
934 lines
27 KiB
C
/**************************************************************************
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*
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* Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA.
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* Copyright 2016 Intel Corporation
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* All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sub license, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice (including the
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* next paragraph) shall be included in all copies or substantial portions
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* of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
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* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
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* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
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* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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* USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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*
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**************************************************************************/
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/*
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* Generic simple memory manager implementation. Intended to be used as a base
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* class implementation for more advanced memory managers.
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*
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* Note that the algorithm used is quite simple and there might be substantial
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* performance gains if a smarter free list is implemented. Currently it is
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* just an unordered stack of free regions. This could easily be improved if
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* an RB-tree is used instead. At least if we expect heavy fragmentation.
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*
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* Aligned allocations can also see improvement.
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*
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* Authors:
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* Thomas Hellström <thomas-at-tungstengraphics-dot-com>
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*/
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#include <drm/drmP.h>
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#include <drm/drm_mm.h>
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#include <linux/slab.h>
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#include <linux/seq_file.h>
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#include <linux/export.h>
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#include <linux/interval_tree_generic.h>
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/**
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* DOC: Overview
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*
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* drm_mm provides a simple range allocator. The drivers are free to use the
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* resource allocator from the linux core if it suits them, the upside of drm_mm
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* is that it's in the DRM core. Which means that it's easier to extend for
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* some of the crazier special purpose needs of gpus.
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*
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* The main data struct is &drm_mm, allocations are tracked in &drm_mm_node.
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* Drivers are free to embed either of them into their own suitable
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* datastructures. drm_mm itself will not do any memory allocations of its own,
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* so if drivers choose not to embed nodes they need to still allocate them
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* themselves.
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*
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* The range allocator also supports reservation of preallocated blocks. This is
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* useful for taking over initial mode setting configurations from the firmware,
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* where an object needs to be created which exactly matches the firmware's
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* scanout target. As long as the range is still free it can be inserted anytime
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* after the allocator is initialized, which helps with avoiding looped
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* dependencies in the driver load sequence.
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*
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* drm_mm maintains a stack of most recently freed holes, which of all
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* simplistic datastructures seems to be a fairly decent approach to clustering
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* allocations and avoiding too much fragmentation. This means free space
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* searches are O(num_holes). Given that all the fancy features drm_mm supports
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* something better would be fairly complex and since gfx thrashing is a fairly
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* steep cliff not a real concern. Removing a node again is O(1).
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*
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* drm_mm supports a few features: Alignment and range restrictions can be
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* supplied. Furthermore every &drm_mm_node has a color value (which is just an
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* opaque unsigned long) which in conjunction with a driver callback can be used
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* to implement sophisticated placement restrictions. The i915 DRM driver uses
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* this to implement guard pages between incompatible caching domains in the
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* graphics TT.
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*
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* Two behaviors are supported for searching and allocating: bottom-up and
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* top-down. The default is bottom-up. Top-down allocation can be used if the
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* memory area has different restrictions, or just to reduce fragmentation.
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*
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* Finally iteration helpers to walk all nodes and all holes are provided as are
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* some basic allocator dumpers for debugging.
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*
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* Note that this range allocator is not thread-safe, drivers need to protect
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* modifications with their on locking. The idea behind this is that for a full
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* memory manager additional data needs to be protected anyway, hence internal
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* locking would be fully redundant.
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*/
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#ifdef CONFIG_DRM_DEBUG_MM
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#include <linux/stackdepot.h>
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#define STACKDEPTH 32
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#define BUFSZ 4096
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static noinline void save_stack(struct drm_mm_node *node)
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{
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unsigned long entries[STACKDEPTH];
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struct stack_trace trace = {
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.entries = entries,
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.max_entries = STACKDEPTH,
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.skip = 1
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};
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save_stack_trace(&trace);
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if (trace.nr_entries != 0 &&
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trace.entries[trace.nr_entries-1] == ULONG_MAX)
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trace.nr_entries--;
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/* May be called under spinlock, so avoid sleeping */
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node->stack = depot_save_stack(&trace, GFP_NOWAIT);
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}
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static void show_leaks(struct drm_mm *mm)
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{
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struct drm_mm_node *node;
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unsigned long entries[STACKDEPTH];
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char *buf;
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buf = kmalloc(BUFSZ, GFP_KERNEL);
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if (!buf)
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return;
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list_for_each_entry(node, drm_mm_nodes(mm), node_list) {
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struct stack_trace trace = {
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.entries = entries,
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.max_entries = STACKDEPTH
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};
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if (!node->stack) {
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DRM_ERROR("node [%08llx + %08llx]: unknown owner\n",
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node->start, node->size);
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continue;
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}
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depot_fetch_stack(node->stack, &trace);
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snprint_stack_trace(buf, BUFSZ, &trace, 0);
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DRM_ERROR("node [%08llx + %08llx]: inserted at\n%s",
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node->start, node->size, buf);
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}
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kfree(buf);
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}
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#undef STACKDEPTH
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#undef BUFSZ
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#else
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static void save_stack(struct drm_mm_node *node) { }
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static void show_leaks(struct drm_mm *mm) { }
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#endif
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#define START(node) ((node)->start)
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#define LAST(node) ((node)->start + (node)->size - 1)
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INTERVAL_TREE_DEFINE(struct drm_mm_node, rb,
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u64, __subtree_last,
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START, LAST, static inline, drm_mm_interval_tree)
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struct drm_mm_node *
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__drm_mm_interval_first(const struct drm_mm *mm, u64 start, u64 last)
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{
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return drm_mm_interval_tree_iter_first((struct rb_root *)&mm->interval_tree,
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start, last);
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}
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EXPORT_SYMBOL(__drm_mm_interval_first);
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static void drm_mm_interval_tree_add_node(struct drm_mm_node *hole_node,
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struct drm_mm_node *node)
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{
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struct drm_mm *mm = hole_node->mm;
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struct rb_node **link, *rb;
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struct drm_mm_node *parent;
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node->__subtree_last = LAST(node);
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if (hole_node->allocated) {
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rb = &hole_node->rb;
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while (rb) {
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parent = rb_entry(rb, struct drm_mm_node, rb);
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if (parent->__subtree_last >= node->__subtree_last)
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break;
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parent->__subtree_last = node->__subtree_last;
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rb = rb_parent(rb);
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}
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rb = &hole_node->rb;
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link = &hole_node->rb.rb_right;
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} else {
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rb = NULL;
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link = &mm->interval_tree.rb_node;
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}
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while (*link) {
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rb = *link;
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parent = rb_entry(rb, struct drm_mm_node, rb);
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if (parent->__subtree_last < node->__subtree_last)
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parent->__subtree_last = node->__subtree_last;
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if (node->start < parent->start)
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link = &parent->rb.rb_left;
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else
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link = &parent->rb.rb_right;
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}
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rb_link_node(&node->rb, rb, link);
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rb_insert_augmented(&node->rb,
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&mm->interval_tree,
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&drm_mm_interval_tree_augment);
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}
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#define RB_INSERT(root, member, expr) do { \
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struct rb_node **link = &root.rb_node, *rb = NULL; \
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u64 x = expr(node); \
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while (*link) { \
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rb = *link; \
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if (x < expr(rb_entry(rb, struct drm_mm_node, member))) \
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link = &rb->rb_left; \
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else \
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link = &rb->rb_right; \
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} \
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rb_link_node(&node->member, rb, link); \
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rb_insert_color(&node->member, &root); \
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} while (0)
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#define HOLE_SIZE(NODE) ((NODE)->hole_size)
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#define HOLE_ADDR(NODE) (__drm_mm_hole_node_start(NODE))
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static void add_hole(struct drm_mm_node *node)
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{
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struct drm_mm *mm = node->mm;
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node->hole_size =
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__drm_mm_hole_node_end(node) - __drm_mm_hole_node_start(node);
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DRM_MM_BUG_ON(!drm_mm_hole_follows(node));
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RB_INSERT(mm->holes_size, rb_hole_size, HOLE_SIZE);
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RB_INSERT(mm->holes_addr, rb_hole_addr, HOLE_ADDR);
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list_add(&node->hole_stack, &mm->hole_stack);
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}
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static void rm_hole(struct drm_mm_node *node)
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{
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DRM_MM_BUG_ON(!drm_mm_hole_follows(node));
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list_del(&node->hole_stack);
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rb_erase(&node->rb_hole_size, &node->mm->holes_size);
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rb_erase(&node->rb_hole_addr, &node->mm->holes_addr);
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node->hole_size = 0;
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DRM_MM_BUG_ON(drm_mm_hole_follows(node));
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}
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static inline struct drm_mm_node *rb_hole_size_to_node(struct rb_node *rb)
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{
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return rb_entry_safe(rb, struct drm_mm_node, rb_hole_size);
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}
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static inline struct drm_mm_node *rb_hole_addr_to_node(struct rb_node *rb)
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{
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return rb_entry_safe(rb, struct drm_mm_node, rb_hole_addr);
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}
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static inline u64 rb_hole_size(struct rb_node *rb)
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{
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return rb_entry(rb, struct drm_mm_node, rb_hole_size)->hole_size;
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}
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static struct drm_mm_node *best_hole(struct drm_mm *mm, u64 size)
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{
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struct rb_node *best = NULL;
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struct rb_node **link = &mm->holes_size.rb_node;
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while (*link) {
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struct rb_node *rb = *link;
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if (size <= rb_hole_size(rb)) {
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link = &rb->rb_left;
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best = rb;
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} else {
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link = &rb->rb_right;
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}
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}
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return rb_hole_size_to_node(best);
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}
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static struct drm_mm_node *find_hole(struct drm_mm *mm, u64 addr)
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{
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struct drm_mm_node *node = NULL;
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struct rb_node **link = &mm->holes_addr.rb_node;
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while (*link) {
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u64 hole_start;
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node = rb_hole_addr_to_node(*link);
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hole_start = __drm_mm_hole_node_start(node);
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if (addr < hole_start)
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link = &node->rb_hole_addr.rb_left;
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else if (addr > hole_start + node->hole_size)
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link = &node->rb_hole_addr.rb_right;
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else
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break;
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}
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return node;
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}
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static struct drm_mm_node *
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first_hole(struct drm_mm *mm,
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u64 start, u64 end, u64 size,
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enum drm_mm_insert_mode mode)
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{
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if (RB_EMPTY_ROOT(&mm->holes_size))
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return NULL;
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switch (mode) {
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default:
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case DRM_MM_INSERT_BEST:
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return best_hole(mm, size);
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case DRM_MM_INSERT_LOW:
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return find_hole(mm, start);
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case DRM_MM_INSERT_HIGH:
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return find_hole(mm, end);
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case DRM_MM_INSERT_EVICT:
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return list_first_entry_or_null(&mm->hole_stack,
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struct drm_mm_node,
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hole_stack);
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}
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}
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static struct drm_mm_node *
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next_hole(struct drm_mm *mm,
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struct drm_mm_node *node,
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enum drm_mm_insert_mode mode)
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{
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switch (mode) {
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default:
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case DRM_MM_INSERT_BEST:
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return rb_hole_size_to_node(rb_next(&node->rb_hole_size));
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case DRM_MM_INSERT_LOW:
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return rb_hole_addr_to_node(rb_next(&node->rb_hole_addr));
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case DRM_MM_INSERT_HIGH:
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return rb_hole_addr_to_node(rb_prev(&node->rb_hole_addr));
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case DRM_MM_INSERT_EVICT:
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node = list_next_entry(node, hole_stack);
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return &node->hole_stack == &mm->hole_stack ? NULL : node;
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}
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}
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/**
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* drm_mm_reserve_node - insert an pre-initialized node
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* @mm: drm_mm allocator to insert @node into
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* @node: drm_mm_node to insert
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*
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* This functions inserts an already set-up &drm_mm_node into the allocator,
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* meaning that start, size and color must be set by the caller. All other
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* fields must be cleared to 0. This is useful to initialize the allocator with
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* preallocated objects which must be set-up before the range allocator can be
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* set-up, e.g. when taking over a firmware framebuffer.
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*
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* Returns:
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* 0 on success, -ENOSPC if there's no hole where @node is.
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*/
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int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node)
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{
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u64 end = node->start + node->size;
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struct drm_mm_node *hole;
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u64 hole_start, hole_end;
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u64 adj_start, adj_end;
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end = node->start + node->size;
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if (unlikely(end <= node->start))
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return -ENOSPC;
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/* Find the relevant hole to add our node to */
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hole = find_hole(mm, node->start);
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if (!hole)
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return -ENOSPC;
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adj_start = hole_start = __drm_mm_hole_node_start(hole);
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adj_end = hole_end = hole_start + hole->hole_size;
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if (mm->color_adjust)
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mm->color_adjust(hole, node->color, &adj_start, &adj_end);
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if (adj_start > node->start || adj_end < end)
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return -ENOSPC;
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node->mm = mm;
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list_add(&node->node_list, &hole->node_list);
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drm_mm_interval_tree_add_node(hole, node);
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node->allocated = true;
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node->hole_size = 0;
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rm_hole(hole);
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if (node->start > hole_start)
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add_hole(hole);
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if (end < hole_end)
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add_hole(node);
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save_stack(node);
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return 0;
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}
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EXPORT_SYMBOL(drm_mm_reserve_node);
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/**
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* drm_mm_insert_node_in_range - ranged search for space and insert @node
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* @mm: drm_mm to allocate from
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* @node: preallocate node to insert
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* @size: size of the allocation
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* @alignment: alignment of the allocation
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* @color: opaque tag value to use for this node
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* @range_start: start of the allowed range for this node
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* @range_end: end of the allowed range for this node
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* @mode: fine-tune the allocation search and placement
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*
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* The preallocated @node must be cleared to 0.
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*
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* Returns:
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* 0 on success, -ENOSPC if there's no suitable hole.
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*/
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int drm_mm_insert_node_in_range(struct drm_mm * const mm,
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struct drm_mm_node * const node,
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u64 size, u64 alignment,
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unsigned long color,
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u64 range_start, u64 range_end,
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enum drm_mm_insert_mode mode)
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{
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struct drm_mm_node *hole;
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u64 remainder_mask;
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DRM_MM_BUG_ON(range_start >= range_end);
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if (unlikely(size == 0 || range_end - range_start < size))
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return -ENOSPC;
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if (alignment <= 1)
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alignment = 0;
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remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;
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for (hole = first_hole(mm, range_start, range_end, size, mode); hole;
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hole = next_hole(mm, hole, mode)) {
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u64 hole_start = __drm_mm_hole_node_start(hole);
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u64 hole_end = hole_start + hole->hole_size;
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u64 adj_start, adj_end;
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u64 col_start, col_end;
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if (mode == DRM_MM_INSERT_LOW && hole_start >= range_end)
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break;
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if (mode == DRM_MM_INSERT_HIGH && hole_end <= range_start)
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break;
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col_start = hole_start;
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col_end = hole_end;
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if (mm->color_adjust)
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mm->color_adjust(hole, color, &col_start, &col_end);
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adj_start = max(col_start, range_start);
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adj_end = min(col_end, range_end);
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if (adj_end <= adj_start || adj_end - adj_start < size)
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continue;
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if (mode == DRM_MM_INSERT_HIGH)
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adj_start = adj_end - size;
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if (alignment) {
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u64 rem;
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if (likely(remainder_mask))
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rem = adj_start & remainder_mask;
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else
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div64_u64_rem(adj_start, alignment, &rem);
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if (rem) {
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adj_start -= rem;
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if (mode != DRM_MM_INSERT_HIGH)
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adj_start += alignment;
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if (adj_start < max(col_start, range_start) ||
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min(col_end, range_end) - adj_start < size)
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continue;
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if (adj_end <= adj_start ||
|
|
adj_end - adj_start < size)
|
|
continue;
|
|
}
|
|
}
|
|
|
|
node->mm = mm;
|
|
node->size = size;
|
|
node->start = adj_start;
|
|
node->color = color;
|
|
node->hole_size = 0;
|
|
|
|
list_add(&node->node_list, &hole->node_list);
|
|
drm_mm_interval_tree_add_node(hole, node);
|
|
node->allocated = true;
|
|
|
|
rm_hole(hole);
|
|
if (adj_start > hole_start)
|
|
add_hole(hole);
|
|
if (adj_start + size < hole_end)
|
|
add_hole(node);
|
|
|
|
save_stack(node);
|
|
return 0;
|
|
}
|
|
|
|
return -ENOSPC;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_insert_node_in_range);
|
|
|
|
/**
|
|
* drm_mm_remove_node - Remove a memory node from the allocator.
|
|
* @node: drm_mm_node to remove
|
|
*
|
|
* This just removes a node from its drm_mm allocator. The node does not need to
|
|
* be cleared again before it can be re-inserted into this or any other drm_mm
|
|
* allocator. It is a bug to call this function on a unallocated node.
|
|
*/
|
|
void drm_mm_remove_node(struct drm_mm_node *node)
|
|
{
|
|
struct drm_mm *mm = node->mm;
|
|
struct drm_mm_node *prev_node;
|
|
|
|
DRM_MM_BUG_ON(!node->allocated);
|
|
DRM_MM_BUG_ON(node->scanned_block);
|
|
|
|
prev_node = list_prev_entry(node, node_list);
|
|
|
|
if (drm_mm_hole_follows(node))
|
|
rm_hole(node);
|
|
|
|
drm_mm_interval_tree_remove(node, &mm->interval_tree);
|
|
list_del(&node->node_list);
|
|
node->allocated = false;
|
|
|
|
if (drm_mm_hole_follows(prev_node))
|
|
rm_hole(prev_node);
|
|
add_hole(prev_node);
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_remove_node);
|
|
|
|
/**
|
|
* drm_mm_replace_node - move an allocation from @old to @new
|
|
* @old: drm_mm_node to remove from the allocator
|
|
* @new: drm_mm_node which should inherit @old's allocation
|
|
*
|
|
* This is useful for when drivers embed the drm_mm_node structure and hence
|
|
* can't move allocations by reassigning pointers. It's a combination of remove
|
|
* and insert with the guarantee that the allocation start will match.
|
|
*/
|
|
void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new)
|
|
{
|
|
DRM_MM_BUG_ON(!old->allocated);
|
|
|
|
*new = *old;
|
|
|
|
list_replace(&old->node_list, &new->node_list);
|
|
rb_replace_node(&old->rb, &new->rb, &old->mm->interval_tree);
|
|
|
|
if (drm_mm_hole_follows(old)) {
|
|
list_replace(&old->hole_stack, &new->hole_stack);
|
|
rb_replace_node(&old->rb_hole_size,
|
|
&new->rb_hole_size,
|
|
&old->mm->holes_size);
|
|
rb_replace_node(&old->rb_hole_addr,
|
|
&new->rb_hole_addr,
|
|
&old->mm->holes_addr);
|
|
}
|
|
|
|
old->allocated = false;
|
|
new->allocated = true;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_replace_node);
|
|
|
|
/**
|
|
* DOC: lru scan roster
|
|
*
|
|
* Very often GPUs need to have continuous allocations for a given object. When
|
|
* evicting objects to make space for a new one it is therefore not most
|
|
* efficient when we simply start to select all objects from the tail of an LRU
|
|
* until there's a suitable hole: Especially for big objects or nodes that
|
|
* otherwise have special allocation constraints there's a good chance we evict
|
|
* lots of (smaller) objects unnecessarily.
|
|
*
|
|
* The DRM range allocator supports this use-case through the scanning
|
|
* interfaces. First a scan operation needs to be initialized with
|
|
* drm_mm_scan_init() or drm_mm_scan_init_with_range(). The driver adds
|
|
* objects to the roster, probably by walking an LRU list, but this can be
|
|
* freely implemented. Eviction candiates are added using
|
|
* drm_mm_scan_add_block() until a suitable hole is found or there are no
|
|
* further evictable objects. Eviction roster metadata is tracked in &struct
|
|
* drm_mm_scan.
|
|
*
|
|
* The driver must walk through all objects again in exactly the reverse
|
|
* order to restore the allocator state. Note that while the allocator is used
|
|
* in the scan mode no other operation is allowed.
|
|
*
|
|
* Finally the driver evicts all objects selected (drm_mm_scan_remove_block()
|
|
* reported true) in the scan, and any overlapping nodes after color adjustment
|
|
* (drm_mm_scan_color_evict()). Adding and removing an object is O(1), and
|
|
* since freeing a node is also O(1) the overall complexity is
|
|
* O(scanned_objects). So like the free stack which needs to be walked before a
|
|
* scan operation even begins this is linear in the number of objects. It
|
|
* doesn't seem to hurt too badly.
|
|
*/
|
|
|
|
/**
|
|
* drm_mm_scan_init_with_range - initialize range-restricted lru scanning
|
|
* @scan: scan state
|
|
* @mm: drm_mm to scan
|
|
* @size: size of the allocation
|
|
* @alignment: alignment of the allocation
|
|
* @color: opaque tag value to use for the allocation
|
|
* @start: start of the allowed range for the allocation
|
|
* @end: end of the allowed range for the allocation
|
|
* @mode: fine-tune the allocation search and placement
|
|
*
|
|
* 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_scan_init_with_range(struct drm_mm_scan *scan,
|
|
struct drm_mm *mm,
|
|
u64 size,
|
|
u64 alignment,
|
|
unsigned long color,
|
|
u64 start,
|
|
u64 end,
|
|
enum drm_mm_insert_mode mode)
|
|
{
|
|
DRM_MM_BUG_ON(start >= end);
|
|
DRM_MM_BUG_ON(!size || size > end - start);
|
|
DRM_MM_BUG_ON(mm->scan_active);
|
|
|
|
scan->mm = mm;
|
|
|
|
if (alignment <= 1)
|
|
alignment = 0;
|
|
|
|
scan->color = color;
|
|
scan->alignment = alignment;
|
|
scan->remainder_mask = is_power_of_2(alignment) ? alignment - 1 : 0;
|
|
scan->size = size;
|
|
scan->mode = mode;
|
|
|
|
DRM_MM_BUG_ON(end <= start);
|
|
scan->range_start = start;
|
|
scan->range_end = end;
|
|
|
|
scan->hit_start = U64_MAX;
|
|
scan->hit_end = 0;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_scan_init_with_range);
|
|
|
|
/**
|
|
* drm_mm_scan_add_block - add a node to the scan list
|
|
* @scan: the active drm_mm scanner
|
|
* @node: drm_mm_node to add
|
|
*
|
|
* Add a node to the scan list that might be freed to make space for the desired
|
|
* hole.
|
|
*
|
|
* Returns:
|
|
* True if a hole has been found, false otherwise.
|
|
*/
|
|
bool drm_mm_scan_add_block(struct drm_mm_scan *scan,
|
|
struct drm_mm_node *node)
|
|
{
|
|
struct drm_mm *mm = scan->mm;
|
|
struct drm_mm_node *hole;
|
|
u64 hole_start, hole_end;
|
|
u64 col_start, col_end;
|
|
u64 adj_start, adj_end;
|
|
|
|
DRM_MM_BUG_ON(node->mm != mm);
|
|
DRM_MM_BUG_ON(!node->allocated);
|
|
DRM_MM_BUG_ON(node->scanned_block);
|
|
node->scanned_block = true;
|
|
mm->scan_active++;
|
|
|
|
/* Remove this block from the node_list so that we enlarge the hole
|
|
* (distance between the end of our previous node and the start of
|
|
* or next), without poisoning the link so that we can restore it
|
|
* later in drm_mm_scan_remove_block().
|
|
*/
|
|
hole = list_prev_entry(node, node_list);
|
|
DRM_MM_BUG_ON(list_next_entry(hole, node_list) != node);
|
|
__list_del_entry(&node->node_list);
|
|
|
|
hole_start = __drm_mm_hole_node_start(hole);
|
|
hole_end = __drm_mm_hole_node_end(hole);
|
|
|
|
col_start = hole_start;
|
|
col_end = hole_end;
|
|
if (mm->color_adjust)
|
|
mm->color_adjust(hole, scan->color, &col_start, &col_end);
|
|
|
|
adj_start = max(col_start, scan->range_start);
|
|
adj_end = min(col_end, scan->range_end);
|
|
if (adj_end <= adj_start || adj_end - adj_start < scan->size)
|
|
return false;
|
|
|
|
if (scan->mode == DRM_MM_INSERT_HIGH)
|
|
adj_start = adj_end - scan->size;
|
|
|
|
if (scan->alignment) {
|
|
u64 rem;
|
|
|
|
if (likely(scan->remainder_mask))
|
|
rem = adj_start & scan->remainder_mask;
|
|
else
|
|
div64_u64_rem(adj_start, scan->alignment, &rem);
|
|
if (rem) {
|
|
adj_start -= rem;
|
|
if (scan->mode != DRM_MM_INSERT_HIGH)
|
|
adj_start += scan->alignment;
|
|
if (adj_start < max(col_start, scan->range_start) ||
|
|
min(col_end, scan->range_end) - adj_start < scan->size)
|
|
return false;
|
|
|
|
if (adj_end <= adj_start ||
|
|
adj_end - adj_start < scan->size)
|
|
return false;
|
|
}
|
|
}
|
|
|
|
scan->hit_start = adj_start;
|
|
scan->hit_end = adj_start + scan->size;
|
|
|
|
DRM_MM_BUG_ON(scan->hit_start >= scan->hit_end);
|
|
DRM_MM_BUG_ON(scan->hit_start < hole_start);
|
|
DRM_MM_BUG_ON(scan->hit_end > hole_end);
|
|
|
|
return true;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_scan_add_block);
|
|
|
|
/**
|
|
* drm_mm_scan_remove_block - remove a node from the scan list
|
|
* @scan: the active drm_mm scanner
|
|
* @node: drm_mm_node to remove
|
|
*
|
|
* Nodes **must** be removed in exactly the reverse order from the scan list as
|
|
* they have been added (e.g. using list_add() as they are added and then
|
|
* list_for_each() over that eviction list to remove), 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_insert_node_in_range_generic() or one of the
|
|
* simpler versions of that function with !DRM_MM_SEARCH_BEST will then return
|
|
* the just freed block (because its at the top of the free_stack list).
|
|
*
|
|
* Returns:
|
|
* True if this block should be evicted, false otherwise. Will always
|
|
* return false when no hole has been found.
|
|
*/
|
|
bool drm_mm_scan_remove_block(struct drm_mm_scan *scan,
|
|
struct drm_mm_node *node)
|
|
{
|
|
struct drm_mm_node *prev_node;
|
|
|
|
DRM_MM_BUG_ON(node->mm != scan->mm);
|
|
DRM_MM_BUG_ON(!node->scanned_block);
|
|
node->scanned_block = false;
|
|
|
|
DRM_MM_BUG_ON(!node->mm->scan_active);
|
|
node->mm->scan_active--;
|
|
|
|
/* During drm_mm_scan_add_block() we decoupled this node leaving
|
|
* its pointers intact. Now that the caller is walking back along
|
|
* the eviction list we can restore this block into its rightful
|
|
* place on the full node_list. To confirm that the caller is walking
|
|
* backwards correctly we check that prev_node->next == node->next,
|
|
* i.e. both believe the same node should be on the other side of the
|
|
* hole.
|
|
*/
|
|
prev_node = list_prev_entry(node, node_list);
|
|
DRM_MM_BUG_ON(list_next_entry(prev_node, node_list) !=
|
|
list_next_entry(node, node_list));
|
|
list_add(&node->node_list, &prev_node->node_list);
|
|
|
|
return (node->start + node->size > scan->hit_start &&
|
|
node->start < scan->hit_end);
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_scan_remove_block);
|
|
|
|
/**
|
|
* drm_mm_scan_color_evict - evict overlapping nodes on either side of hole
|
|
* @scan: drm_mm scan with target hole
|
|
*
|
|
* After completing an eviction scan and removing the selected nodes, we may
|
|
* need to remove a few more nodes from either side of the target hole if
|
|
* mm.color_adjust is being used.
|
|
*
|
|
* Returns:
|
|
* A node to evict, or NULL if there are no overlapping nodes.
|
|
*/
|
|
struct drm_mm_node *drm_mm_scan_color_evict(struct drm_mm_scan *scan)
|
|
{
|
|
struct drm_mm *mm = scan->mm;
|
|
struct drm_mm_node *hole;
|
|
u64 hole_start, hole_end;
|
|
|
|
DRM_MM_BUG_ON(list_empty(&mm->hole_stack));
|
|
|
|
if (!mm->color_adjust)
|
|
return NULL;
|
|
|
|
hole = list_first_entry(&mm->hole_stack, typeof(*hole), hole_stack);
|
|
hole_start = __drm_mm_hole_node_start(hole);
|
|
hole_end = hole_start + hole->hole_size;
|
|
|
|
DRM_MM_BUG_ON(hole_start > scan->hit_start);
|
|
DRM_MM_BUG_ON(hole_end < scan->hit_end);
|
|
|
|
mm->color_adjust(hole, scan->color, &hole_start, &hole_end);
|
|
if (hole_start > scan->hit_start)
|
|
return hole;
|
|
if (hole_end < scan->hit_end)
|
|
return list_next_entry(hole, node_list);
|
|
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_scan_color_evict);
|
|
|
|
/**
|
|
* drm_mm_init - initialize a drm-mm allocator
|
|
* @mm: the drm_mm structure to initialize
|
|
* @start: start of the range managed by @mm
|
|
* @size: end of the range managed by @mm
|
|
*
|
|
* Note that @mm must be cleared to 0 before calling this function.
|
|
*/
|
|
void drm_mm_init(struct drm_mm *mm, u64 start, u64 size)
|
|
{
|
|
DRM_MM_BUG_ON(start + size <= start);
|
|
|
|
mm->color_adjust = NULL;
|
|
|
|
INIT_LIST_HEAD(&mm->hole_stack);
|
|
mm->interval_tree = RB_ROOT;
|
|
mm->holes_size = RB_ROOT;
|
|
mm->holes_addr = RB_ROOT;
|
|
|
|
/* Clever trick to avoid a special case in the free hole tracking. */
|
|
INIT_LIST_HEAD(&mm->head_node.node_list);
|
|
mm->head_node.allocated = false;
|
|
mm->head_node.mm = mm;
|
|
mm->head_node.start = start + size;
|
|
mm->head_node.size = -size;
|
|
add_hole(&mm->head_node);
|
|
|
|
mm->scan_active = 0;
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_init);
|
|
|
|
/**
|
|
* drm_mm_takedown - clean up a drm_mm allocator
|
|
* @mm: drm_mm allocator to clean up
|
|
*
|
|
* Note that it is a bug to call this function on an allocator which is not
|
|
* clean.
|
|
*/
|
|
void drm_mm_takedown(struct drm_mm *mm)
|
|
{
|
|
if (WARN(!drm_mm_clean(mm),
|
|
"Memory manager not clean during takedown.\n"))
|
|
show_leaks(mm);
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_takedown);
|
|
|
|
static u64 drm_mm_dump_hole(struct drm_printer *p, const struct drm_mm_node *entry)
|
|
{
|
|
u64 start, size;
|
|
|
|
size = entry->hole_size;
|
|
if (size) {
|
|
start = drm_mm_hole_node_start(entry);
|
|
drm_printf(p, "%#018llx-%#018llx: %llu: free\n",
|
|
start, start + size, size);
|
|
}
|
|
|
|
return size;
|
|
}
|
|
/**
|
|
* drm_mm_print - print allocator state
|
|
* @mm: drm_mm allocator to print
|
|
* @p: DRM printer to use
|
|
*/
|
|
void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p)
|
|
{
|
|
const struct drm_mm_node *entry;
|
|
u64 total_used = 0, total_free = 0, total = 0;
|
|
|
|
total_free += drm_mm_dump_hole(p, &mm->head_node);
|
|
|
|
drm_mm_for_each_node(entry, mm) {
|
|
drm_printf(p, "%#018llx-%#018llx: %llu: used\n", entry->start,
|
|
entry->start + entry->size, entry->size);
|
|
total_used += entry->size;
|
|
total_free += drm_mm_dump_hole(p, entry);
|
|
}
|
|
total = total_free + total_used;
|
|
|
|
drm_printf(p, "total: %llu, used %llu free %llu\n", total,
|
|
total_used, total_free);
|
|
}
|
|
EXPORT_SYMBOL(drm_mm_print);
|