]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/char/drm/drm_mm.c
drm: don't cast a pointer to pointer of list_head
[linux-2.6-omap-h63xx.git] / drivers / char / drm / drm_mm.c
index 617526bd5b0ca6703b365ca07e9a2187ef8342f5..dcff9e9b52e327016ee53590a98ea8b21d44d362 100644 (file)
  * Aligned allocations can also see improvement.
  *
  * Authors:
- * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
+ * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
  */
 
 #include "drmP.h"
+#include <linux/slab.h>
 
-drm_mm_node_t *drm_mm_get_block(drm_mm_node_t * parent,
+unsigned long drm_mm_tail_space(struct drm_mm *mm)
+{
+       struct list_head *tail_node;
+       struct drm_mm_node *entry;
+
+       tail_node = mm->ml_entry.prev;
+       entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
+       if (!entry->free)
+               return 0;
+
+       return entry->size;
+}
+
+int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size)
+{
+       struct list_head *tail_node;
+       struct drm_mm_node *entry;
+
+       tail_node = mm->ml_entry.prev;
+       entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
+       if (!entry->free)
+               return -ENOMEM;
+
+       if (entry->size <= size)
+               return -ENOMEM;
+
+       entry->size -= size;
+       return 0;
+}
+
+
+static int drm_mm_create_tail_node(struct drm_mm *mm,
+                           unsigned long start,
+                           unsigned long size)
+{
+       struct drm_mm_node *child;
+
+       child = (struct drm_mm_node *)
+               drm_alloc(sizeof(*child), DRM_MEM_MM);
+       if (!child)
+               return -ENOMEM;
+
+       child->free = 1;
+       child->size = size;
+       child->start = start;
+       child->mm = mm;
+
+       list_add_tail(&child->ml_entry, &mm->ml_entry);
+       list_add_tail(&child->fl_entry, &mm->fl_entry);
+
+       return 0;
+}
+
+
+int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size)
+{
+       struct list_head *tail_node;
+       struct drm_mm_node *entry;
+
+       tail_node = mm->ml_entry.prev;
+       entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
+       if (!entry->free) {
+               return drm_mm_create_tail_node(mm, entry->start + entry->size, size);
+       }
+       entry->size += size;
+       return 0;
+}
+
+static struct drm_mm_node *drm_mm_split_at_start(struct drm_mm_node *parent,
+                                           unsigned long size)
+{
+       struct drm_mm_node *child;
+
+       child = (struct drm_mm_node *)
+               drm_alloc(sizeof(*child), DRM_MEM_MM);
+       if (!child)
+               return NULL;
+
+       INIT_LIST_HEAD(&child->fl_entry);
+
+       child->free = 0;
+       child->size = size;
+       child->start = parent->start;
+       child->mm = parent->mm;
+
+       list_add_tail(&child->ml_entry, &parent->ml_entry);
+       INIT_LIST_HEAD(&child->fl_entry);
+
+       parent->size -= size;
+       parent->start += size;
+       return child;
+}
+
+
+
+struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
                                unsigned long size, unsigned alignment)
 {
 
-       drm_mm_node_t *child;
+       struct drm_mm_node *align_splitoff = NULL;
+       struct drm_mm_node *child;
+       unsigned tmp = 0;
 
        if (alignment)
-               size += alignment - 1;
+               tmp = parent->start % alignment;
+
+       if (tmp) {
+               align_splitoff = drm_mm_split_at_start(parent, alignment - tmp);
+               if (!align_splitoff)
+                       return NULL;
+       }
 
        if (parent->size == size) {
                list_del_init(&parent->fl_entry);
                parent->free = 0;
                return parent;
        } else {
-               child = (drm_mm_node_t *) drm_alloc(sizeof(*child), DRM_MEM_MM);
-               if (!child)
-                       return NULL;
-
-               INIT_LIST_HEAD(&child->ml_entry);
-               INIT_LIST_HEAD(&child->fl_entry);
+               child = drm_mm_split_at_start(parent, size);
+       }
 
-               child->free = 0;
-               child->size = size;
-               child->start = parent->start;
+       if (align_splitoff)
+               drm_mm_put_block(align_splitoff);
 
-               list_add_tail(&child->ml_entry, &parent->ml_entry);
-               parent->size -= size;
-               parent->start += size;
-       }
        return child;
 }
 
@@ -80,26 +175,26 @@ drm_mm_node_t *drm_mm_get_block(drm_mm_node_t * parent,
  * Otherwise add to the free stack.
  */
 
-void drm_mm_put_block(drm_mm_t * mm, drm_mm_node_t * cur)
+void drm_mm_put_block(struct drm_mm_node * cur)
 {
 
-       drm_mm_node_t *list_root = &mm->root_node;
+       struct drm_mm *mm = cur->mm;
        struct list_head *cur_head = &cur->ml_entry;
-       struct list_head *root_head = &list_root->ml_entry;
-       drm_mm_node_t *prev_node = NULL;
-       drm_mm_node_t *next_node;
+       struct list_head *root_head = &mm->ml_entry;
+       struct drm_mm_node *prev_node = NULL;
+       struct drm_mm_node *next_node;
 
        int merged = 0;
 
        if (cur_head->prev != root_head) {
-               prev_node = list_entry(cur_head->prev, drm_mm_node_t, ml_entry);
+               prev_node = list_entry(cur_head->prev, struct drm_mm_node, ml_entry);
                if (prev_node->free) {
                        prev_node->size += cur->size;
                        merged = 1;
                }
        }
        if (cur_head->next != root_head) {
-               next_node = list_entry(cur_head->next, drm_mm_node_t, ml_entry);
+               next_node = list_entry(cur_head->next, struct drm_mm_node, ml_entry);
                if (next_node->free) {
                        if (merged) {
                                prev_node->size += next_node->size;
@@ -116,32 +211,42 @@ void drm_mm_put_block(drm_mm_t * mm, drm_mm_node_t * cur)
        }
        if (!merged) {
                cur->free = 1;
-               list_add(&cur->fl_entry, &list_root->fl_entry);
+               list_add(&cur->fl_entry, &mm->fl_entry);
        } else {
                list_del(&cur->ml_entry);
                drm_free(cur, sizeof(*cur), DRM_MEM_MM);
        }
 }
 
-drm_mm_node_t *drm_mm_search_free(const drm_mm_t * mm,
+struct drm_mm_node *drm_mm_search_free(const struct drm_mm * mm,
                                  unsigned long size,
                                  unsigned alignment, int best_match)
 {
        struct list_head *list;
-       const struct list_head *free_stack = &mm->root_node.fl_entry;
-       drm_mm_node_t *entry;
-       drm_mm_node_t *best;
+       const struct list_head *free_stack = &mm->fl_entry;
+       struct drm_mm_node *entry;
+       struct drm_mm_node *best;
        unsigned long best_size;
+       unsigned wasted;
 
        best = NULL;
        best_size = ~0UL;
 
-       if (alignment)
-               size += alignment - 1;
-
        list_for_each(list, free_stack) {
-               entry = list_entry(list, drm_mm_node_t, fl_entry);
-               if (entry->size >= size) {
+               entry = list_entry(list, struct drm_mm_node, fl_entry);
+               wasted = 0;
+
+               if (entry->size < size)
+                       continue;
+
+               if (alignment) {
+                       register unsigned tmp = entry->start % alignment;
+                       if (tmp)
+                               wasted += alignment - tmp;
+               }
+
+
+               if (entry->size >= size + wasted) {
                        if (!best_match)
                                return entry;
                        if (size < best_size) {
@@ -154,40 +259,31 @@ drm_mm_node_t *drm_mm_search_free(const drm_mm_t * mm,
        return best;
 }
 
-int drm_mm_init(drm_mm_t * mm, unsigned long start, unsigned long size)
+int drm_mm_clean(struct drm_mm * mm)
 {
-       drm_mm_node_t *child;
-
-       INIT_LIST_HEAD(&mm->root_node.ml_entry);
-       INIT_LIST_HEAD(&mm->root_node.fl_entry);
-       child = (drm_mm_node_t *) drm_alloc(sizeof(*child), DRM_MEM_MM);
-       if (!child)
-               return -ENOMEM;
+       struct list_head *head = &mm->ml_entry;
 
-       INIT_LIST_HEAD(&child->ml_entry);
-       INIT_LIST_HEAD(&child->fl_entry);
-
-       child->start = start;
-       child->size = size;
-       child->free = 1;
+       return (head->next->next == head);
+}
 
-       list_add(&child->fl_entry, &mm->root_node.fl_entry);
-       list_add(&child->ml_entry, &mm->root_node.ml_entry);
+int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size)
+{
+       INIT_LIST_HEAD(&mm->ml_entry);
+       INIT_LIST_HEAD(&mm->fl_entry);
 
-       return 0;
+       return drm_mm_create_tail_node(mm, start, size);
 }
 
-EXPORT_SYMBOL(drm_mm_init);
 
-void drm_mm_takedown(drm_mm_t * mm)
+void drm_mm_takedown(struct drm_mm * mm)
 {
-       struct list_head *bnode = mm->root_node.fl_entry.next;
-       drm_mm_node_t *entry;
+       struct list_head *bnode = mm->fl_entry.next;
+       struct drm_mm_node *entry;
 
-       entry = list_entry(bnode, drm_mm_node_t, fl_entry);
+       entry = list_entry(bnode, struct drm_mm_node, fl_entry);
 
-       if (entry->ml_entry.next != &mm->root_node.ml_entry ||
-           entry->fl_entry.next != &mm->root_node.fl_entry) {
+       if (entry->ml_entry.next != &mm->ml_entry ||
+           entry->fl_entry.next != &mm->fl_entry) {
                DRM_ERROR("Memory manager not clean. Delaying takedown\n");
                return;
        }
@@ -197,5 +293,3 @@ void drm_mm_takedown(drm_mm_t * mm)
 
        drm_free(entry, sizeof(*entry), DRM_MEM_MM);
 }
-
-EXPORT_SYMBOL(drm_mm_takedown);