[PATCH 4/8] drm: make vma-manager entries untyped

David Herrmann dh.herrmann at gmail.com
Wed Aug 3 18:04:28 UTC 2016


Right now, the vma-manager requires all entries to provide a "struct
file*" as identifier. This is confusing, since there is no inherent
connection to "struct file" in the vma-manager at all, but it is
exclusively used as tag.

Replace its usage with a simple "void *tag" and make sure callers can use
arbitrary tags.

Signed-off-by: David Herrmann <dh.herrmann at gmail.com>
---
 drivers/gpu/drm/drm_vma_manager.c | 40 +++++++++++++++++++--------------------
 include/drm/drm_vma_manager.h     | 18 ++++++++----------
 2 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/drm_vma_manager.c b/drivers/gpu/drm/drm_vma_manager.c
index f306c88..954248e 100644
--- a/drivers/gpu/drm/drm_vma_manager.c
+++ b/drivers/gpu/drm/drm_vma_manager.c
@@ -25,7 +25,6 @@
 #include <drm/drmP.h>
 #include <drm/drm_mm.h>
 #include <drm/drm_vma_manager.h>
-#include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/rbtree.h>
@@ -277,9 +276,9 @@ EXPORT_SYMBOL(drm_vma_offset_remove);
 /**
  * drm_vma_node_allow - Add open-file to list of allowed users
  * @node: Node to modify
- * @filp: Open file to add
+ * @tag: Tag of file to remove
  *
- * Add @filp to the list of allowed open-files for this node. If @filp is
+ * Add @tag to the list of allowed open-files for this node. If @tag is
  * already on this list, the ref-count is incremented.
  *
  * The list of allowed-users is preserved across drm_vma_offset_add() and
@@ -294,7 +293,7 @@ EXPORT_SYMBOL(drm_vma_offset_remove);
  * RETURNS:
  * 0 on success, negative error code on internal failure (out-of-mem)
  */
-int drm_vma_node_allow(struct drm_vma_offset_node *node, struct file *filp)
+int drm_vma_node_allow(struct drm_vma_offset_node *node, void *tag)
 {
 	struct rb_node **iter;
 	struct rb_node *parent = NULL;
@@ -315,10 +314,10 @@ int drm_vma_node_allow(struct drm_vma_offset_node *node, struct file *filp)
 		parent = *iter;
 		entry = rb_entry(*iter, struct drm_vma_offset_file, vm_rb);
 
-		if (filp == entry->vm_filp) {
+		if (tag == entry->vm_tag) {
 			entry->vm_count++;
 			goto unlock;
-		} else if (filp > entry->vm_filp) {
+		} else if (tag > entry->vm_tag) {
 			iter = &(*iter)->rb_right;
 		} else {
 			iter = &(*iter)->rb_left;
@@ -330,7 +329,7 @@ int drm_vma_node_allow(struct drm_vma_offset_node *node, struct file *filp)
 		goto unlock;
 	}
 
-	new->vm_filp = filp;
+	new->vm_tag = tag;
 	new->vm_count = 1;
 	rb_link_node(&new->vm_rb, parent, iter);
 	rb_insert_color(&new->vm_rb, &node->vm_files);
@@ -346,17 +345,17 @@ EXPORT_SYMBOL(drm_vma_node_allow);
 /**
  * drm_vma_node_revoke - Remove open-file from list of allowed users
  * @node: Node to modify
- * @filp: Open file to remove
+ * @tag: Tag of file to remove
  *
- * Decrement the ref-count of @filp in the list of allowed open-files on @node.
- * If the ref-count drops to zero, remove @filp from the list. You must call
- * this once for every drm_vma_node_allow() on @filp.
+ * Decrement the ref-count of @tag in the list of allowed open-files on @node.
+ * If the ref-count drops to zero, remove @tag from the list. You must call
+ * this once for every drm_vma_node_allow() on @tag.
  *
  * This is locked against concurrent access internally.
  *
- * If @filp is not on the list, nothing is done.
+ * If @tag is not on the list, nothing is done.
  */
-void drm_vma_node_revoke(struct drm_vma_offset_node *node, struct file *filp)
+void drm_vma_node_revoke(struct drm_vma_offset_node *node, void *tag)
 {
 	struct drm_vma_offset_file *entry;
 	struct rb_node *iter;
@@ -366,13 +365,13 @@ void drm_vma_node_revoke(struct drm_vma_offset_node *node, struct file *filp)
 	iter = node->vm_files.rb_node;
 	while (likely(iter)) {
 		entry = rb_entry(iter, struct drm_vma_offset_file, vm_rb);
-		if (filp == entry->vm_filp) {
+		if (tag == entry->vm_tag) {
 			if (!--entry->vm_count) {
 				rb_erase(&entry->vm_rb, &node->vm_files);
 				kfree(entry);
 			}
 			break;
-		} else if (filp > entry->vm_filp) {
+		} else if (tag > entry->vm_tag) {
 			iter = iter->rb_right;
 		} else {
 			iter = iter->rb_left;
@@ -386,9 +385,9 @@ EXPORT_SYMBOL(drm_vma_node_revoke);
 /**
  * drm_vma_node_is_allowed - Check whether an open-file is granted access
  * @node: Node to check
- * @filp: Open-file to check for
+ * @tag: Tag of file to remove
  *
- * Search the list in @node whether @filp is currently on the list of allowed
+ * Search the list in @node whether @tag is currently on the list of allowed
  * open-files (see drm_vma_node_allow()).
  *
  * This is locked against concurrent access internally.
@@ -396,8 +395,7 @@ EXPORT_SYMBOL(drm_vma_node_revoke);
  * RETURNS:
  * true iff @filp is on the list
  */
-bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node,
-			     struct file *filp)
+bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node, void *tag)
 {
 	struct drm_vma_offset_file *entry;
 	struct rb_node *iter;
@@ -407,9 +405,9 @@ bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node,
 	iter = node->vm_files.rb_node;
 	while (likely(iter)) {
 		entry = rb_entry(iter, struct drm_vma_offset_file, vm_rb);
-		if (filp == entry->vm_filp)
+		if (tag == entry->vm_tag)
 			break;
-		else if (filp > entry->vm_filp)
+		else if (tag > entry->vm_tag)
 			iter = iter->rb_right;
 		else
 			iter = iter->rb_left;
diff --git a/include/drm/drm_vma_manager.h b/include/drm/drm_vma_manager.h
index 06ea8e07..6edc968 100644
--- a/include/drm/drm_vma_manager.h
+++ b/include/drm/drm_vma_manager.h
@@ -24,7 +24,6 @@
  */
 
 #include <drm/drm_mm.h>
-#include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/rbtree.h>
@@ -33,7 +32,7 @@
 
 struct drm_vma_offset_file {
 	struct rb_node vm_rb;
-	struct file *vm_filp;
+	void *vm_tag;
 	unsigned long vm_count;
 };
 
@@ -62,10 +61,9 @@ int drm_vma_offset_add(struct drm_vma_offset_manager *mgr,
 void drm_vma_offset_remove(struct drm_vma_offset_manager *mgr,
 			   struct drm_vma_offset_node *node);
 
-int drm_vma_node_allow(struct drm_vma_offset_node *node, struct file *filp);
-void drm_vma_node_revoke(struct drm_vma_offset_node *node, struct file *filp);
-bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node,
-			     struct file *filp);
+int drm_vma_node_allow(struct drm_vma_offset_node *node, void *tag);
+void drm_vma_node_revoke(struct drm_vma_offset_node *node, void *tag);
+bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node, void *tag);
 
 /**
  * drm_vma_offset_exact_lookup_locked() - Look up node by exact address
@@ -216,9 +214,9 @@ static inline void drm_vma_node_unmap(struct drm_vma_offset_node *node,
 /**
  * drm_vma_node_verify_access() - Access verification helper for TTM
  * @node: Offset node
- * @filp: Open-file
+ * @tag: Tag of file to check
  *
- * This checks whether @filp is granted access to @node. It is the same as
+ * This checks whether @tag is granted access to @node. It is the same as
  * drm_vma_node_is_allowed() but suitable as drop-in helper for TTM
  * verify_access() callbacks.
  *
@@ -226,9 +224,9 @@ static inline void drm_vma_node_unmap(struct drm_vma_offset_node *node,
  * 0 if access is granted, -EACCES otherwise.
  */
 static inline int drm_vma_node_verify_access(struct drm_vma_offset_node *node,
-					     struct file *filp)
+					     void *tag)
 {
-	return drm_vma_node_is_allowed(node, filp) ? 0 : -EACCES;
+	return drm_vma_node_is_allowed(node, tag) ? 0 : -EACCES;
 }
 
 #endif /* __DRM_VMA_MANAGER_H__ */
-- 
2.9.2



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