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diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h
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+/**************************************************************************
+ *
+ * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. USA.
+ * Copyright 2016 Intel Corporation
+ * 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.
+ *
+ *
+ **************************************************************************/
+/*
+ * Authors:
+ * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
+ */
+
+#ifndef _DRM_MM_H_
+#define _DRM_MM_H_
+
+/*
+ * Generic range manager structs
+ */
+#include <linux/bug.h>
+#include <linux/rbtree.h>
+#include <linux/kernel.h>
+#include <linux/mm_types.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#ifdef CONFIG_DRM_DEBUG_MM
+#include <linux/stackdepot.h>
+#endif
+#include <drm/drm_print.h>
+
+#ifdef CONFIG_DRM_DEBUG_MM
+#define DRM_MM_BUG_ON(expr) BUG_ON(expr)
+#else
+#define DRM_MM_BUG_ON(expr) BUILD_BUG_ON_INVALID(expr)
+#endif
+
+/**
+ * enum drm_mm_insert_mode - control search and allocation behaviour
+ *
+ * The &struct drm_mm range manager supports finding a suitable modes using
+ * a number of search trees. These trees are oranised by size, by address and
+ * in most recent eviction order. This allows the user to find either the
+ * smallest hole to reuse, the lowest or highest address to reuse, or simply
+ * reuse the most recent eviction that fits. When allocating the &drm_mm_node
+ * from within the hole, the &drm_mm_insert_mode also dictate whether to
+ * allocate the lowest matching address or the highest.
+ */
+enum drm_mm_insert_mode {
+ /**
+ * @DRM_MM_INSERT_BEST:
+ *
+ * Search for the smallest hole (within the search range) that fits
+ * the desired node.
+ *
+ * Allocates the node from the bottom of the found hole.
+ */
+ DRM_MM_INSERT_BEST = 0,
+
+ /**
+ * @DRM_MM_INSERT_LOW:
+ *
+ * Search for the lowest hole (address closest to 0, within the search
+ * range) that fits the desired node.
+ *
+ * Allocates the node from the bottom of the found hole.
+ */
+ DRM_MM_INSERT_LOW,
+
+ /**
+ * @DRM_MM_INSERT_HIGH:
+ *
+ * Search for the highest hole (address closest to U64_MAX, within the
+ * search range) that fits the desired node.
+ *
+ * Allocates the node from the *top* of the found hole. The specified
+ * alignment for the node is applied to the base of the node
+ * (&drm_mm_node.start).
+ */
+ DRM_MM_INSERT_HIGH,
+
+ /**
+ * @DRM_MM_INSERT_EVICT:
+ *
+ * Search for the most recently evicted hole (within the search range)
+ * that fits the desired node. This is appropriate for use immediately
+ * after performing an eviction scan (see drm_mm_scan_init()) and
+ * removing the selected nodes to form a hole.
+ *
+ * Allocates the node from the bottom of the found hole.
+ */
+ DRM_MM_INSERT_EVICT,
+
+ /**
+ * @DRM_MM_INSERT_ONCE:
+ *
+ * Only check the first hole for suitablity and report -ENOSPC
+ * immediately otherwise, rather than check every hole until a
+ * suitable one is found. Can only be used in conjunction with another
+ * search method such as DRM_MM_INSERT_HIGH or DRM_MM_INSERT_LOW.
+ */
+ DRM_MM_INSERT_ONCE = BIT(31),
+
+ /**
+ * @DRM_MM_INSERT_HIGHEST:
+ *
+ * Only check the highest hole (the hole with the largest address) and
+ * insert the node at the top of the hole or report -ENOSPC if
+ * unsuitable.
+ *
+ * Does not search all holes.
+ */
+ DRM_MM_INSERT_HIGHEST = DRM_MM_INSERT_HIGH | DRM_MM_INSERT_ONCE,
+
+ /**
+ * @DRM_MM_INSERT_LOWEST:
+ *
+ * Only check the lowest hole (the hole with the smallest address) and
+ * insert the node at the bottom of the hole or report -ENOSPC if
+ * unsuitable.
+ *
+ * Does not search all holes.
+ */
+ DRM_MM_INSERT_LOWEST = DRM_MM_INSERT_LOW | DRM_MM_INSERT_ONCE,
+};
+
+/**
+ * struct drm_mm_node - allocated block in the DRM allocator
+ *
+ * This represents an allocated block in a &drm_mm allocator. Except for
+ * pre-reserved nodes inserted using drm_mm_reserve_node() the structure is
+ * entirely opaque and should only be accessed through the provided funcions.
+ * Since allocation of these nodes is entirely handled by the driver they can be
+ * embedded.
+ */
+struct drm_mm_node {
+ /** @color: Opaque driver-private tag. */
+ unsigned long color;
+ /** @start: Start address of the allocated block. */
+ u64 start;
+ /** @size: Size of the allocated block. */
+ u64 size;
+ /* private: */
+ struct drm_mm *mm;
+ struct list_head node_list;
+ struct list_head hole_stack;
+ struct rb_node rb;
+ struct rb_node rb_hole_size;
+ struct rb_node rb_hole_addr;
+ u64 __subtree_last;
+ u64 hole_size;
+ u64 subtree_max_hole;
+ unsigned long flags;
+#define DRM_MM_NODE_ALLOCATED_BIT 0
+#define DRM_MM_NODE_SCANNED_BIT 1
+#ifdef CONFIG_DRM_DEBUG_MM
+ depot_stack_handle_t stack;
+#endif
+};
+
+/**
+ * struct drm_mm - DRM allocator
+ *
+ * DRM range allocator with a few special functions and features geared towards
+ * managing GPU memory. Except for the @color_adjust callback the structure is
+ * entirely opaque and should only be accessed through the provided functions
+ * and macros. This structure can be embedded into larger driver structures.
+ */
+struct drm_mm {
+ /**
+ * @color_adjust:
+ *
+ * Optional driver callback to further apply restrictions on a hole. The
+ * node argument points at the node containing the hole from which the
+ * block would be allocated (see drm_mm_hole_follows() and friends). The
+ * other arguments are the size of the block to be allocated. The driver
+ * can adjust the start and end as needed to e.g. insert guard pages.
+ */
+ void (*color_adjust)(const struct drm_mm_node *node,
+ unsigned long color,
+ u64 *start, u64 *end);
+
+ /* private: */
+ /* List of all memory nodes that immediately precede a free hole. */
+ struct list_head hole_stack;
+ /* head_node.node_list is the list of all memory nodes, ordered
+ * according to the (increasing) start address of the memory node. */
+ struct drm_mm_node head_node;
+ /* Keep an interval_tree for fast lookup of drm_mm_nodes by address. */
+ struct rb_root_cached interval_tree;
+ struct rb_root_cached holes_size;
+ struct rb_root holes_addr;
+
+ unsigned long scan_active;
+};
+
+/**
+ * struct drm_mm_scan - DRM allocator eviction roaster data
+ *
+ * This structure tracks data needed for the eviction roaster set up using
+ * drm_mm_scan_init(), and used with drm_mm_scan_add_block() and
+ * drm_mm_scan_remove_block(). The structure is entirely opaque and should only
+ * be accessed through the provided functions and macros. It is meant to be
+ * allocated temporarily by the driver on the stack.
+ */
+struct drm_mm_scan {
+ /* private: */
+ struct drm_mm *mm;
+
+ u64 size;
+ u64 alignment;
+ u64 remainder_mask;
+
+ u64 range_start;
+ u64 range_end;
+
+ u64 hit_start;
+ u64 hit_end;
+
+ unsigned long color;
+ enum drm_mm_insert_mode mode;
+};
+
+/**
+ * drm_mm_node_allocated - checks whether a node is allocated
+ * @node: drm_mm_node to check
+ *
+ * Drivers are required to clear a node prior to using it with the
+ * drm_mm range manager.
+ *
+ * Drivers should use this helper for proper encapsulation of drm_mm
+ * internals.
+ *
+ * Returns:
+ * True if the @node is allocated.
+ */
+static inline bool drm_mm_node_allocated(const struct drm_mm_node *node)
+{
+ return test_bit(DRM_MM_NODE_ALLOCATED_BIT, &node->flags);
+}
+
+/**
+ * drm_mm_initialized - checks whether an allocator is initialized
+ * @mm: drm_mm to check
+ *
+ * Drivers should clear the struct drm_mm prior to initialisation if they
+ * want to use this function.
+ *
+ * Drivers should use this helper for proper encapsulation of drm_mm
+ * internals.
+ *
+ * Returns:
+ * True if the @mm is initialized.
+ */
+static inline bool drm_mm_initialized(const struct drm_mm *mm)
+{
+ return READ_ONCE(mm->hole_stack.next);
+}
+
+/**
+ * drm_mm_hole_follows - checks whether a hole follows this node
+ * @node: drm_mm_node to check
+ *
+ * Holes are embedded into the drm_mm using the tail of a drm_mm_node.
+ * If you wish to know whether a hole follows this particular node,
+ * query this function. See also drm_mm_hole_node_start() and
+ * drm_mm_hole_node_end().
+ *
+ * Returns:
+ * True if a hole follows the @node.
+ */
+static inline bool drm_mm_hole_follows(const struct drm_mm_node *node)
+{
+ return node->hole_size;
+}
+
+static inline u64 __drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
+{
+ return hole_node->start + hole_node->size;
+}
+
+/**
+ * drm_mm_hole_node_start - computes the start of the hole following @node
+ * @hole_node: drm_mm_node which implicitly tracks the following hole
+ *
+ * This is useful for driver-specific debug dumpers. Otherwise drivers should
+ * not inspect holes themselves. Drivers must check first whether a hole indeed
+ * follows by looking at drm_mm_hole_follows()
+ *
+ * Returns:
+ * Start of the subsequent hole.
+ */
+static inline u64 drm_mm_hole_node_start(const struct drm_mm_node *hole_node)
+{
+ DRM_MM_BUG_ON(!drm_mm_hole_follows(hole_node));
+ return __drm_mm_hole_node_start(hole_node);
+}
+
+static inline u64 __drm_mm_hole_node_end(const struct drm_mm_node *hole_node)
+{
+ return list_next_entry(hole_node, node_list)->start;
+}
+
+/**
+ * drm_mm_hole_node_end - computes the end of the hole following @node
+ * @hole_node: drm_mm_node which implicitly tracks the following hole
+ *
+ * This is useful for driver-specific debug dumpers. Otherwise drivers should
+ * not inspect holes themselves. Drivers must check first whether a hole indeed
+ * follows by looking at drm_mm_hole_follows().
+ *
+ * Returns:
+ * End of the subsequent hole.
+ */
+static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node)
+{
+ return __drm_mm_hole_node_end(hole_node);
+}
+
+/**
+ * drm_mm_nodes - list of nodes under the drm_mm range manager
+ * @mm: the struct drm_mm range manager
+ *
+ * As the drm_mm range manager hides its node_list deep with its
+ * structure, extracting it looks painful and repetitive. This is
+ * not expected to be used outside of the drm_mm_for_each_node()
+ * macros and similar internal functions.
+ *
+ * Returns:
+ * The node list, may be empty.
+ */
+#define drm_mm_nodes(mm) (&(mm)->head_node.node_list)
+
+/**
+ * drm_mm_for_each_node - iterator to walk over all allocated nodes
+ * @entry: &struct drm_mm_node to assign to in each iteration step
+ * @mm: &drm_mm allocator to walk
+ *
+ * This iterator walks over all nodes in the range allocator. It is implemented
+ * with list_for_each(), so not save against removal of elements.
+ */
+#define drm_mm_for_each_node(entry, mm) \
+ list_for_each_entry(entry, drm_mm_nodes(mm), node_list)
+
+/**
+ * drm_mm_for_each_node_safe - iterator to walk over all allocated nodes
+ * @entry: &struct drm_mm_node to assign to in each iteration step
+ * @next: &struct drm_mm_node to store the next step
+ * @mm: &drm_mm allocator to walk
+ *
+ * This iterator walks over all nodes in the range allocator. It is implemented
+ * with list_for_each_safe(), so save against removal of elements.
+ */
+#define drm_mm_for_each_node_safe(entry, next, mm) \
+ list_for_each_entry_safe(entry, next, drm_mm_nodes(mm), node_list)
+
+/**
+ * drm_mm_for_each_hole - iterator to walk over all holes
+ * @pos: &drm_mm_node used internally to track progress
+ * @mm: &drm_mm allocator to walk
+ * @hole_start: ulong variable to assign the hole start to on each iteration
+ * @hole_end: ulong variable to assign the hole end to on each iteration
+ *
+ * This iterator walks over all holes in the range allocator. It is implemented
+ * with list_for_each(), so not save against removal of elements. @entry is used
+ * internally and will not reflect a real drm_mm_node for the very first hole.
+ * Hence users of this iterator may not access it.
+ *
+ * Implementation Note:
+ * We need to inline list_for_each_entry in order to be able to set hole_start
+ * and hole_end on each iteration while keeping the macro sane.
+ */
+#define drm_mm_for_each_hole(pos, mm, hole_start, hole_end) \
+ for (pos = list_first_entry(&(mm)->hole_stack, \
+ typeof(*pos), hole_stack); \
+ &pos->hole_stack != &(mm)->hole_stack ? \
+ hole_start = drm_mm_hole_node_start(pos), \
+ hole_end = hole_start + pos->hole_size, \
+ 1 : 0; \
+ pos = list_next_entry(pos, hole_stack))
+
+/*
+ * Basic range manager support (drm_mm.c)
+ */
+int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node);
+int drm_mm_insert_node_in_range(struct drm_mm *mm,
+ struct drm_mm_node *node,
+ u64 size,
+ u64 alignment,
+ unsigned long color,
+ u64 start,
+ u64 end,
+ enum drm_mm_insert_mode mode);
+
+/**
+ * drm_mm_insert_node_generic - search for space and insert @node
+ * @mm: drm_mm to allocate from
+ * @node: preallocate node to insert
+ * @size: size of the allocation
+ * @alignment: alignment of the allocation
+ * @color: opaque tag value to use for this node
+ * @mode: fine-tune the allocation search and placement
+ *
+ * This is a simplified version of drm_mm_insert_node_in_range() with no
+ * range restrictions applied.
+ *
+ * The preallocated node must be cleared to 0.
+ *
+ * Returns:
+ * 0 on success, -ENOSPC if there's no suitable hole.
+ */
+static inline int
+drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node,
+ u64 size, u64 alignment,
+ unsigned long color,
+ enum drm_mm_insert_mode mode)
+{
+ return drm_mm_insert_node_in_range(mm, node,
+ size, alignment, color,
+ 0, U64_MAX, mode);
+}
+
+/**
+ * drm_mm_insert_node - search for space and insert @node
+ * @mm: drm_mm to allocate from
+ * @node: preallocate node to insert
+ * @size: size of the allocation
+ *
+ * This is a simplified version of drm_mm_insert_node_generic() with @color set
+ * to 0.
+ *
+ * The preallocated node must be cleared to 0.
+ *
+ * Returns:
+ * 0 on success, -ENOSPC if there's no suitable hole.
+ */
+static inline int drm_mm_insert_node(struct drm_mm *mm,
+ struct drm_mm_node *node,
+ u64 size)
+{
+ return drm_mm_insert_node_generic(mm, node, size, 0, 0, 0);
+}
+
+void drm_mm_remove_node(struct drm_mm_node *node);
+void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new);
+void drm_mm_init(struct drm_mm *mm, u64 start, u64 size);
+void drm_mm_takedown(struct drm_mm *mm);
+
+/**
+ * drm_mm_clean - checks whether an allocator is clean
+ * @mm: drm_mm allocator to check
+ *
+ * Returns:
+ * True if the allocator is completely free, false if there's still a node
+ * allocated in it.
+ */
+static inline bool drm_mm_clean(const struct drm_mm *mm)
+{
+ return list_empty(drm_mm_nodes(mm));
+}
+
+struct drm_mm_node *
+__drm_mm_interval_first(const struct drm_mm *mm, u64 start, u64 last);
+
+/**
+ * drm_mm_for_each_node_in_range - iterator to walk over a range of
+ * allocated nodes
+ * @node__: drm_mm_node structure to assign to in each iteration step
+ * @mm__: drm_mm allocator to walk
+ * @start__: starting offset, the first node will overlap this
+ * @end__: ending offset, the last node will start before this (but may overlap)
+ *
+ * This iterator walks over all nodes in the range allocator that lie
+ * between @start and @end. It is implemented similarly to list_for_each(),
+ * but using the internal interval tree to accelerate the search for the
+ * starting node, and so not safe against removal of elements. It assumes
+ * that @end is within (or is the upper limit of) the drm_mm allocator.
+ * If [@start, @end] are beyond the range of the drm_mm, the iterator may walk
+ * over the special _unallocated_ &drm_mm.head_node, and may even continue
+ * indefinitely.
+ */
+#define drm_mm_for_each_node_in_range(node__, mm__, start__, end__) \
+ for (node__ = __drm_mm_interval_first((mm__), (start__), (end__)-1); \
+ node__->start < (end__); \
+ node__ = list_next_entry(node__, node_list))
+
+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_scan_init - initialize 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
+ * @mode: fine-tune the allocation search and placement
+ *
+ * This is a simplified version of drm_mm_scan_init_with_range() with no range
+ * restrictions applied.
+ *
+ * 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.
+ */
+static inline void drm_mm_scan_init(struct drm_mm_scan *scan,
+ struct drm_mm *mm,
+ u64 size,
+ u64 alignment,
+ unsigned long color,
+ enum drm_mm_insert_mode mode)
+{
+ drm_mm_scan_init_with_range(scan, mm,
+ size, alignment, color,
+ 0, U64_MAX, mode);
+}
+
+bool drm_mm_scan_add_block(struct drm_mm_scan *scan,
+ struct drm_mm_node *node);
+bool drm_mm_scan_remove_block(struct drm_mm_scan *scan,
+ struct drm_mm_node *node);
+struct drm_mm_node *drm_mm_scan_color_evict(struct drm_mm_scan *scan);
+
+void drm_mm_print(const struct drm_mm *mm, struct drm_printer *p);
+
+#endif