@@ -53,9 +53,9 @@ static struct drm_mm_node *drm_mm_kmalloc(struct drm_mm *mm, int atomic)
struct drm_mm_node *child;
if (atomic)
- child = kmalloc(sizeof(*child), GFP_ATOMIC);
+ child = kzalloc(sizeof(*child), GFP_ATOMIC);
else
- child = kmalloc(sizeof(*child), GFP_KERNEL);
+ child = kzalloc(sizeof(*child), GFP_KERNEL);
if (unlikely(child == NULL)) {
spin_lock(&mm->unused_lock);
@@ -85,7 +85,7 @@ int drm_mm_pre_get(struct drm_mm *mm)
spin_lock(&mm->unused_lock);
while (mm->num_unused < MM_UNUSED_TARGET) {
spin_unlock(&mm->unused_lock);
- node = kmalloc(sizeof(*node), GFP_KERNEL);
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
spin_lock(&mm->unused_lock);
if (unlikely(node == NULL)) {
@@ -134,7 +134,6 @@ static struct drm_mm_node *drm_mm_split_at_start(struct drm_mm_node *parent,
INIT_LIST_HEAD(&child->free_stack);
- child->free = 0;
child->size = size;
child->start = parent->start;
child->mm = parent->mm;
@@ -235,6 +234,9 @@ void drm_mm_put_block(struct drm_mm_node *cur)
int merged = 0;
+ BUG_ON(cur->scanned_block || cur->scanned_prev_free
+ || cur->scanned_next_free);
+
if (cur_head->prev != root_head) {
prev_node =
list_entry(cur_head->prev, struct drm_mm_node, node_list);
@@ -312,6 +314,8 @@ struct drm_mm_node *drm_mm_search_free(const struct drm_mm *mm,
struct drm_mm_node *best;
unsigned long best_size;
+ BUG_ON(mm->scanned_blocks);
+
best = NULL;
best_size = ~0UL;
@@ -343,6 +347,8 @@ struct drm_mm_node *drm_mm_search_free_in_range(const struct drm_mm *mm,
struct drm_mm_node *best;
unsigned long best_size;
+ BUG_ON(mm->scanned_blocks);
+
best = NULL;
best_size = ~0UL;
@@ -366,6 +372,158 @@ struct drm_mm_node *drm_mm_search_free_in_range(const struct drm_mm *mm,
}
EXPORT_SYMBOL(drm_mm_search_free_in_range);
+/**
+ * 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)
+{
+ mm->scan_alignment = alignment;
+ mm->scan_size = size;
+ mm->scanned_blocks = 0;
+ mm->scan_hit_start = 0;
+ mm->scan_hit_size = 0;
+}
+EXPORT_SYMBOL(drm_mm_init_scan);
+
+/**
+ * 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 list_head *prev_free, *next_free;
+ struct drm_mm_node *prev_node, *next_node;
+
+ mm->scanned_blocks++;
+
+ prev_free = next_free = NULL;
+
+ BUG_ON(node->free);
+ node->scanned_block = 1;
+ node->free = 1;
+
+ if (node->node_list.prev != &mm->node_list) {
+ prev_node = list_entry(node->node_list.prev, struct drm_mm_node,
+ node_list);
+
+ if (prev_node->free) {
+ list_del(&prev_node->node_list);
+
+ node->start = prev_node->start;
+ node->size += prev_node->size;
+
+ prev_node->scanned_prev_free = 1;
+
+ prev_free = &prev_node->free_stack;
+ }
+ }
+
+ if (node->node_list.next != &mm->node_list) {
+ next_node = list_entry(node->node_list.next, struct drm_mm_node,
+ node_list);
+
+ if (next_node->free) {
+ list_del(&next_node->node_list);
+
+ node->size += next_node->size;
+
+ next_node->scanned_next_free = 1;
+
+ next_free = &next_node->free_stack;
+ }
+ }
+
+ /* The free_stack list is not used for allocated objects, so these two
+ * pointers can be abused (as long as no allocations in this memory
+ * manager happens). */
+ node->free_stack.prev = prev_free;
+ node->free_stack.next = next_free;
+
+ if (check_free_mm_node(node, mm->scan_size, mm->scan_alignment)) {
+ mm->scan_hit_start = node->start;
+ mm->scan_hit_size = node->size;
+
+ 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
+ * immediatly 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, *next_node;
+
+ mm->scanned_blocks--;
+
+ BUG_ON(!node->scanned_block);
+ node->scanned_block = 0;
+ node->free = 0;
+
+ prev_node = list_entry(node->free_stack.prev, struct drm_mm_node,
+ free_stack);
+ next_node = list_entry(node->free_stack.next, struct drm_mm_node,
+ free_stack);
+
+ if (prev_node) {
+ BUG_ON(!prev_node->scanned_prev_free);
+ prev_node->scanned_prev_free = 0;
+
+ list_add_tail(&prev_node->node_list, &node->node_list);
+
+ node->start = prev_node->start + prev_node->size;
+ node->size -= prev_node->size;
+ }
+
+ if (next_node) {
+ BUG_ON(!next_node->scanned_next_free);
+ next_node->scanned_next_free = 0;
+
+ list_add(&next_node->node_list, &node->node_list);
+
+ node->size -= next_node->size;
+ }
+
+ INIT_LIST_HEAD(&node->free_stack);
+
+ /* Only need to check for containement because start&size for the
+ * complete resulting free block (not just the desired part) is
+ * stored. */
+ if (node->start >= mm->scan_hit_start &&
+ node->start + node->size
+ <= mm->scan_hit_start + mm->scan_hit_size) {
+ return 1;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_mm_scan_remove_block);
+
int drm_mm_clean(struct drm_mm * mm)
{
struct list_head *head = &mm->node_list;
@@ -380,6 +538,7 @@ int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size)
INIT_LIST_HEAD(&mm->free_stack);
INIT_LIST_HEAD(&mm->unused_nodes);
mm->num_unused = 0;
+ mm->scanned_blocks = 0;
spin_lock_init(&mm->unused_lock);
return drm_mm_create_tail_node(mm, start, size, 0);
@@ -44,7 +44,10 @@
struct drm_mm_node {
struct list_head free_stack;
struct list_head node_list;
- int free;
+ unsigned free : 1;
+ unsigned scanned_block : 1;
+ unsigned scanned_prev_free : 1;
+ unsigned scanned_next_free : 1;
unsigned long start;
unsigned long size;
struct drm_mm *mm;
@@ -59,6 +62,11 @@ struct drm_mm {
struct list_head unused_nodes;
int num_unused;
spinlock_t unused_lock;
+ unsigned scan_alignment;
+ unsigned long scan_size;
+ unsigned long scan_hit_start;
+ unsigned scan_hit_size;
+ unsigned scanned_blocks;
};
/*
@@ -135,6 +143,11 @@ static inline struct drm_mm *drm_get_mm(struct drm_mm_node *block)
return block->mm;
}
+void drm_mm_init_scan(struct drm_mm *mm, unsigned long size,
+ unsigned alignment);
+int drm_mm_scan_add_block(struct drm_mm_node *node);
+int drm_mm_scan_remove_block(struct drm_mm_node *node);
+
extern void drm_mm_debug_table(struct drm_mm *mm, const char *prefix);
#ifdef CONFIG_DEBUG_FS
int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm);