drm: Split out the mm declarations in a separate header. Add atomic operations.

this is a TTM preparation patch, it rearranges the mm and
add operations needed to do mm operations in atomic context.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

3 files changed, 228 insertions, 64 deletions

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index 367c590..7819fd9 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -42,8 +42,11 @@
  */
 
 #include "drmP.h"
+#include "drm_mm.h"
 #include <linux/slab.h>
 
+#define MM_UNUSED_TARGET 4
+
 unsigned long drm_mm_tail_space(struct drm_mm *mm)
 {
 	struct list_head *tail_node;
@@ -74,16 +77,62 @@ int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size)
 	return 0;
 }
 
+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);
+	else
+		child = kmalloc(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, fl_entry);
+			list_del(&child->fl_entry);
+			--mm->num_unused;
+		}
+		spin_unlock(&mm->unused_lock);
+	}
+	return child;
+}
+
+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 = kmalloc(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->fl_entry, &mm->unused_nodes);
+	}
+	spin_unlock(&mm->unused_lock);
+	return 0;
+}
+EXPORT_SYMBOL(drm_mm_pre_get);
 
 static int drm_mm_create_tail_node(struct drm_mm *mm,
-			    unsigned long start,
-			    unsigned long size)
+				   unsigned long start,
+				   unsigned long size, int atomic)
 {
 	struct drm_mm_node *child;
 
-	child = (struct drm_mm_node *)
-		drm_alloc(sizeof(*child), DRM_MEM_MM);
-	if (!child)
+	child = drm_mm_kmalloc(mm, atomic);
+	if (unlikely(child == NULL))
 		return -ENOMEM;
 
 	child->free = 1;
@@ -97,8 +146,7 @@ static int drm_mm_create_tail_node(struct drm_mm *mm,
 	return 0;
 }
 
-
-int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size)
+int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size, int atomic)
 {
 	struct list_head *tail_node;
 	struct drm_mm_node *entry;
@@ -106,20 +154,21 @@ int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size)
 	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);
+		return drm_mm_create_tail_node(mm, entry->start + entry->size,
+					       size, atomic);
 	}
 	entry->size += size;
 	return 0;
 }
 
 static struct drm_mm_node *drm_mm_split_at_start(struct drm_mm_node *parent,
-					    unsigned long size)
+						 unsigned long size,
+						 int atomic)
 {
 	struct drm_mm_node *child;
 
-	child = (struct drm_mm_node *)
-		drm_alloc(sizeof(*child), DRM_MEM_MM);
-	if (!child)
+	child = drm_mm_kmalloc(parent->mm, atomic);
+	if (unlikely(child == NULL))
 		return NULL;
 
 	INIT_LIST_HEAD(&child->fl_entry);
@@ -151,8 +200,9 @@ struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
 		tmp = parent->start % alignment;
 
 	if (tmp) {
-		align_splitoff = drm_mm_split_at_start(parent, alignment - tmp);
-		if (!align_splitoff)
+		align_splitoff =
+		    drm_mm_split_at_start(parent, alignment - tmp, 0);
+		if (unlikely(align_splitoff == NULL))
 			return NULL;
 	}
 
@@ -161,7 +211,7 @@ struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
 		parent->free = 0;
 		return parent;
 	} else {
-		child = drm_mm_split_at_start(parent, size);
+		child = drm_mm_split_at_start(parent, size, 0);
 	}
 
 	if (align_splitoff)
@@ -169,14 +219,49 @@ struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
 
 	return child;
 }
+
 EXPORT_SYMBOL(drm_mm_get_block);
 
+struct drm_mm_node *drm_mm_get_block_atomic(struct drm_mm_node *parent,
+					    unsigned long size,
+					    unsigned alignment)
+{
+
+	struct drm_mm_node *align_splitoff = NULL;
+	struct drm_mm_node *child;
+	unsigned tmp = 0;
+
+	if (alignment)
+		tmp = parent->start % alignment;
+
+	if (tmp) {
+		align_splitoff =
+		    drm_mm_split_at_start(parent, alignment - tmp, 1);
+		if (unlikely(align_splitoff == NULL))
+			return NULL;
+	}
+
+	if (parent->size == size) {
+		list_del_init(&parent->fl_entry);
+		parent->free = 0;
+		return parent;
+	} else {
+		child = drm_mm_split_at_start(parent, size, 1);
+	}
+
+	if (align_splitoff)
+		drm_mm_put_block(align_splitoff);
+
+	return child;
+}
+EXPORT_SYMBOL(drm_mm_get_block_atomic);
+
 /*
  * Put a block. Merge with the previous and / or next block if they are free.
  * Otherwise add to the free stack.
  */
 
-void drm_mm_put_block(struct drm_mm_node * cur)
+void drm_mm_put_block(struct drm_mm_node *cur)
 {
 
 	struct drm_mm *mm = cur->mm;
@@ -188,21 +273,27 @@ void drm_mm_put_block(struct drm_mm_node * cur)
 	int merged = 0;
 
 	if (cur_head->prev != root_head) {
-		prev_node = list_entry(cur_head->prev, struct drm_mm_node, 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, struct drm_mm_node, 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;
 				list_del(&next_node->ml_entry);
 				list_del(&next_node->fl_entry);
-				drm_free(next_node, sizeof(*next_node),
-					 DRM_MEM_MM);
+				if (mm->num_unused < MM_UNUSED_TARGET) {
+					list_add(&next_node->fl_entry,
+						 &mm->unused_nodes);
+					++mm->num_unused;
+				} else
+					kfree(next_node);
 			} else {
 				next_node->size += cur->size;
 				next_node->start = cur->start;
@@ -215,14 +306,19 @@ void drm_mm_put_block(struct drm_mm_node * cur)
 		list_add(&cur->fl_entry, &mm->fl_entry);
 	} else {
 		list_del(&cur->ml_entry);
-		drm_free(cur, sizeof(*cur), DRM_MEM_MM);
+		if (mm->num_unused < MM_UNUSED_TARGET) {
+			list_add(&cur->fl_entry, &mm->unused_nodes);
+			++mm->num_unused;
+		} else
+			kfree(cur);
 	}
 }
+
 EXPORT_SYMBOL(drm_mm_put_block);
 
-struct drm_mm_node *drm_mm_search_free(const struct drm_mm * mm,
-				  unsigned long size,
-				  unsigned alignment, int best_match)
+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->fl_entry;
@@ -247,7 +343,6 @@ struct drm_mm_node *drm_mm_search_free(const struct drm_mm * mm,
 				wasted += alignment - tmp;
 		}
 
-
 		if (entry->size >= size + wasted) {
 			if (!best_match)
 				return entry;
@@ -260,6 +355,7 @@ struct drm_mm_node *drm_mm_search_free(const struct drm_mm * mm,
 
 	return best;
 }
+EXPORT_SYMBOL(drm_mm_search_free);
 
 int drm_mm_clean(struct drm_mm * mm)
 {
@@ -267,14 +363,17 @@ int drm_mm_clean(struct drm_mm * mm)
 
 	return (head->next->next == head);
 }
-EXPORT_SYMBOL(drm_mm_search_free);
+EXPORT_SYMBOL(drm_mm_clean);
 
 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);
+	INIT_LIST_HEAD(&mm->unused_nodes);
+	mm->num_unused = 0;
+	spin_lock_init(&mm->unused_lock);
 
-	return drm_mm_create_tail_node(mm, start, size);
+	return drm_mm_create_tail_node(mm, start, size, 0);
 }
 EXPORT_SYMBOL(drm_mm_init);
 
@@ -282,6 +381,7 @@ void drm_mm_takedown(struct drm_mm * mm)
 {
 	struct list_head *bnode = mm->fl_entry.next;
 	struct drm_mm_node *entry;
+	struct drm_mm_node *next;
 
 	entry = list_entry(bnode, struct drm_mm_node, fl_entry);
 
@@ -293,7 +393,16 @@ void drm_mm_takedown(struct drm_mm * mm)
 
 	list_del(&entry->fl_entry);
 	list_del(&entry->ml_entry);
+	kfree(entry);
+
+	spin_lock(&mm->unused_lock);
+	list_for_each_entry_safe(entry, next, &mm->unused_nodes, fl_entry) {
+		list_del(&entry->fl_entry);
+		kfree(entry);
+		--mm->num_unused;
+	}
+	spin_unlock(&mm->unused_lock);
 
-	drm_free(entry, sizeof(*entry), DRM_MEM_MM);
+	BUG_ON(mm->num_unused != 0);
 }
 EXPORT_SYMBOL(drm_mm_takedown);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 1cc51a0..d4ddc22 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -86,6 +86,7 @@ struct drm_device;
 
 #include "drm_os_linux.h"
 #include "drm_hashtab.h"
+#include "drm_mm.h"
 
 #define DRM_UT_CORE 		0x01
 #define DRM_UT_DRIVER		0x02
@@ -553,26 +554,6 @@ struct drm_sigdata {
 };
 
 
-/*
- * Generic memory manager structs
- */
-
-struct drm_mm_node {
-	struct list_head fl_entry;
-	struct list_head ml_entry;
-	int free;
-	unsigned long start;
-	unsigned long size;
-	struct drm_mm *mm;
-	void *private;
-};
-
-struct drm_mm {
-	struct list_head fl_entry;
-	struct list_head ml_entry;
-};
-
-
 /**
  * Kernel side of a mapping
  */
@@ -1436,22 +1417,6 @@ extern char *drm_get_connector_status_name(enum drm_connector_status status);
 extern int drm_sysfs_connector_add(struct drm_connector *connector);
 extern void drm_sysfs_connector_remove(struct drm_connector *connector);
 
-/*
- * Basic memory manager support (drm_mm.c)
- */
-extern struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
-				       unsigned long size,
-				       unsigned alignment);
-extern void drm_mm_put_block(struct drm_mm_node * cur);
-extern struct drm_mm_node *drm_mm_search_free(const struct drm_mm *mm, unsigned long size,
-					 unsigned alignment, int best_match);
-extern int drm_mm_init(struct drm_mm *mm, unsigned long start, unsigned long size);
-extern void drm_mm_takedown(struct drm_mm *mm);
-extern int drm_mm_clean(struct drm_mm *mm);
-extern unsigned long drm_mm_tail_space(struct drm_mm *mm);
-extern int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size);
-extern int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size);
-
 /* Graphics Execution Manager library functions (drm_gem.c) */
 int drm_gem_init(struct drm_device *dev);
 void drm_gem_destroy(struct drm_device *dev);
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h
new file mode 100644
index 0000000..5662f42
--- /dev/null
+++ b/include/drm/drm_mm.h
@@ -0,0 +1,90 @@
+/**************************************************************************
+ *
+ * Copyright 2006-2008 Tungsten Graphics, Inc., Cedar Park, TX. 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.
+ *
+ *
+ **************************************************************************/
+/*
+ * Authors:
+ * Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
+ */
+
+#ifndef _DRM_MM_H_
+#define _DRM_MM_H_
+
+/*
+ * Generic range manager structs
+ */
+#include <linux/list.h>
+
+struct drm_mm_node {
+	struct list_head fl_entry;
+	struct list_head ml_entry;
+	int free;
+	unsigned long start;
+	unsigned long size;
+	struct drm_mm *mm;
+	void *private;
+};
+
+struct drm_mm {
+	struct list_head fl_entry;
+	struct list_head ml_entry;
+	struct list_head unused_nodes;
+	int num_unused;
+	spinlock_t unused_lock;
+};
+
+/*
+ * Basic range manager support (drm_mm.c)
+ */
+
+extern struct drm_mm_node *drm_mm_get_block(struct drm_mm_node *parent,
+					    unsigned long size,
+					    unsigned alignment);
+extern struct drm_mm_node *drm_mm_get_block_atomic(struct drm_mm_node *parent,
+						   unsigned long size,
+						   unsigned alignment);
+extern void drm_mm_put_block(struct drm_mm_node *cur);
+extern struct drm_mm_node *drm_mm_search_free(const struct drm_mm *mm,
+					      unsigned long size,
+					      unsigned alignment,
+					      int best_match);
+extern int drm_mm_init(struct drm_mm *mm, unsigned long start,
+		       unsigned long size);
+extern void drm_mm_takedown(struct drm_mm *mm);
+extern int drm_mm_clean(struct drm_mm *mm);
+extern unsigned long drm_mm_tail_space(struct drm_mm *mm);
+extern int drm_mm_remove_space_from_tail(struct drm_mm *mm,
+					 unsigned long size);
+extern int drm_mm_add_space_to_tail(struct drm_mm *mm,
+				    unsigned long size, int atomic);
+extern int drm_mm_pre_get(struct drm_mm *mm);
+
+static inline struct drm_mm *drm_get_mm(struct drm_mm_node *block)
+{
+	return block->mm;
+}
+
+#endif