drm/vmwgfx: return -EFAULT for copy_to_user errors

[safe/jmp/linux-2.6] / kernel / resource.c

diff --git a/kernel/resource.c b/kernel/resource.c
index 91f430f..7b36976 100644 (file)
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -15,6 +15,7 @@
 #include <linux/spinlock.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
+#include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/device.h>
 #include <linux/pfn.h>
@@ -188,20 +189,65 @@ static int __release_resource(struct resource *old)
        return -EINVAL;
 }
 
+static void __release_child_resources(struct resource *r)
+{
+       struct resource *tmp, *p;
+       resource_size_t size;
+
+       p = r->child;
+       r->child = NULL;
+       while (p) {
+               tmp = p;
+               p = p->sibling;
+
+               tmp->parent = NULL;
+               tmp->sibling = NULL;
+               __release_child_resources(tmp);
+
+               printk(KERN_DEBUG "release child resource %pR\n", tmp);
+               /* need to restore size, and keep flags */
+               size = resource_size(tmp);
+               tmp->start = 0;
+               tmp->end = size - 1;
+       }
+}
+
+void release_child_resources(struct resource *r)
+{
+       write_lock(&resource_lock);
+       __release_child_resources(r);
+       write_unlock(&resource_lock);
+}
+
 /**
- * request_resource - request and reserve an I/O or memory resource
+ * request_resource_conflict - request and reserve an I/O or memory resource
  * @root: root resource descriptor
  * @new: resource descriptor desired by caller
  *
- * Returns 0 for success, negative error code on error.
+ * Returns 0 for success, conflict resource on error.
  */
-int request_resource(struct resource *root, struct resource *new)
+struct resource *request_resource_conflict(struct resource *root, struct resource *new)
 {
        struct resource *conflict;
 
        write_lock(&resource_lock);
        conflict = __request_resource(root, new);
        write_unlock(&resource_lock);
+       return conflict;
+}
+
+/**
+ * request_resource - request and reserve an I/O or memory resource
+ * @root: root resource descriptor
+ * @new: resource descriptor desired by caller
+ *
+ * Returns 0 for success, negative error code on error.
+ */
+int request_resource(struct resource *root, struct resource *new)
+{
+       struct resource *conflict;
+
+       conflict = request_resource_conflict(root, new);
        return conflict ? -EBUSY : 0;
 }
 
@@ -317,8 +363,10 @@ int __weak page_is_ram(unsigned long pfn)
 static int find_resource(struct resource *root, struct resource *new,
                         resource_size_t size, resource_size_t min,
                         resource_size_t max, resource_size_t align,
-                        void (*alignf)(void *, struct resource *,
-                                       resource_size_t, resource_size_t),
+                        resource_size_t (*alignf)(void *,
+                                                  const struct resource *,
+                                                  resource_size_t,
+                                                  resource_size_t),
                         void *alignf_data)
 {
        struct resource *this = root->child;
@@ -344,7 +392,7 @@ static int find_resource(struct resource *root, struct resource *new,
                        tmp.end = max;
                tmp.start = ALIGN(tmp.start, align);
                if (alignf)
-                       alignf(alignf_data, &tmp, size, align);
+                       tmp.start = alignf(alignf_data, &tmp, size, align);
                if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) {
                        new->start = tmp.start;
                        new->end = tmp.start + size - 1;
@@ -372,8 +420,10 @@ static int find_resource(struct resource *root, struct resource *new,
 int allocate_resource(struct resource *root, struct resource *new,
                      resource_size_t size, resource_size_t min,
                      resource_size_t max, resource_size_t align,
-                     void (*alignf)(void *, struct resource *,
-                                    resource_size_t, resource_size_t),
+                     resource_size_t (*alignf)(void *,
+                                               const struct resource *,
+                                               resource_size_t,
+                                               resource_size_t),
                      void *alignf_data)
 {
        int err;
@@ -440,25 +490,40 @@ static struct resource * __insert_resource(struct resource *parent, struct resou
 }
 
 /**
- * insert_resource - Inserts a resource in the resource tree
+ * insert_resource_conflict - Inserts resource in the resource tree
  * @parent: parent of the new resource
  * @new: new resource to insert
  *
- * Returns 0 on success, -EBUSY if the resource can't be inserted.
+ * Returns 0 on success, conflict resource if the resource can't be inserted.
  *
- * This function is equivalent to request_resource when no conflict
+ * This function is equivalent to request_resource_conflict when no conflict
  * happens. If a conflict happens, and the conflicting resources
  * entirely fit within the range of the new resource, then the new
  * resource is inserted and the conflicting resources become children of
  * the new resource.
  */
-int insert_resource(struct resource *parent, struct resource *new)
+struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
 {
        struct resource *conflict;
 
        write_lock(&resource_lock);
        conflict = __insert_resource(parent, new);
        write_unlock(&resource_lock);
+       return conflict;
+}
+
+/**
+ * insert_resource - Inserts a resource in the resource tree
+ * @parent: parent of the new resource
+ * @new: new resource to insert
+ *
+ * Returns 0 on success, -EBUSY if the resource can't be inserted.
+ */
+int insert_resource(struct resource *parent, struct resource *new)
+{
+       struct resource *conflict;
+
+       conflict = insert_resource_conflict(parent, new);
        return conflict ? -EBUSY : 0;
 }
 
@@ -617,6 +682,8 @@ resource_size_t resource_alignment(struct resource *res)
  * release_region releases a matching busy region.
  */
 
+static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
+
 /**
  * __request_region - create a new busy resource region
  * @parent: parent resource descriptor
@@ -629,6 +696,7 @@ struct resource * __request_region(struct resource *parent,
                                   resource_size_t start, resource_size_t n,
                                   const char *name, int flags)
 {
+       DECLARE_WAITQUEUE(wait, current);
        struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
 
        if (!res)
@@ -653,7 +721,15 @@ struct resource * __request_region(struct resource *parent,
                        if (!(conflict->flags & IORESOURCE_BUSY))
                                continue;
                }
-
+               if (conflict->flags & flags & IORESOURCE_MUXED) {
+                       add_wait_queue(&muxed_resource_wait, &wait);
+                       write_unlock(&resource_lock);
+                       set_current_state(TASK_UNINTERRUPTIBLE);
+                       schedule();
+                       remove_wait_queue(&muxed_resource_wait, &wait);
+                       write_lock(&resource_lock);
+                       continue;
+               }
                /* Uhhuh, that didn't work out.. */
                kfree(res);
                res = NULL;
@@ -727,6 +803,8 @@ void __release_region(struct resource *parent, resource_size_t start,
                                break;
                        *p = res->sibling;
                        write_unlock(&resource_lock);
+                       if (res->flags & IORESOURCE_MUXED)
+                               wake_up(&muxed_resource_wait);
                        kfree(res);
                        return;
                }