drm: convert drawable code to using idr

This converts the code for allocating drawables to the Linux idr,

Fixes from: Michel Dänzer <michel@tungstengraphics.com>, Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/drmP.h

@@ -751,10 +751,7 @@ struct drm_device {
 	/** \name Drawable information */
 	/*@{ */
 	spinlock_t drw_lock;
-	unsigned int drw_bitfield_length;
-	u32 *drw_bitfield;
-	unsigned int drw_info_length;
-	struct drm_drawable_info **drw_info;
+	struct idr drw_idr;
 	/*@} */
 };
 
@@ -904,6 +901,7 @@ extern int drm_update_drawable_info(struct inode *inode, struct file *filp,
 		       unsigned int cmd, unsigned long arg);
 extern struct drm_drawable_info *drm_get_drawable_info(struct drm_device *dev,
 						  drm_drawable_t id);
+extern void drm_drawable_free_all(struct drm_device *dev);
 
 				/* Authentication IOCTL support (drm_auth.h) */
 extern int drm_getmagic(struct inode *inode, struct file *filp,

drivers/char/drm/drm_drawable.c

@@ -44,82 +44,29 @@ int drm_adddraw(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	unsigned long irqflags;
-	int i, j;
-	u32 *bitfield = dev->drw_bitfield;
-	unsigned int bitfield_length = dev->drw_bitfield_length;
-	struct drm_drawable_info **info = dev->drw_info;
-	unsigned int info_length = dev->drw_info_length;
 	struct drm_draw draw;
+	int new_id = 0;
+	int ret;
 
-	for (i = 0, j = 0; i < bitfield_length; i++) {
-		if (bitfield[i] == ~0)
-			continue;
-
-		for (; j < 8 * sizeof(*bitfield); j++)
-			if (!(bitfield[i] & (1 << j)))
-				goto done;
-	}
-done:
-
-	if (i == bitfield_length) {
-		bitfield_length++;
-
-		bitfield = drm_alloc(bitfield_length * sizeof(*bitfield),
-				     DRM_MEM_BUFS);
-
-		if (!bitfield) {
-			DRM_ERROR("Failed to allocate new drawable bitfield\n");
-			return DRM_ERR(ENOMEM);
-		}
-
-		if (8 * sizeof(*bitfield) * bitfield_length > info_length) {
-			info_length += 8 * sizeof(*bitfield);
-
-			info = drm_alloc(info_length * sizeof(*info),
-					 DRM_MEM_BUFS);
-
-			if (!info) {
-				DRM_ERROR("Failed to allocate new drawable info"
-					  " array\n");
-
-				drm_free(bitfield,
-					 bitfield_length * sizeof(*bitfield),
-					 DRM_MEM_BUFS);
-				return DRM_ERR(ENOMEM);
-			}
-		}
-
-		bitfield[i] = 0;
+again:
+	if (idr_pre_get(&dev->drw_idr, GFP_KERNEL) == 0) {
+		DRM_ERROR("Out of memory expanding drawable idr\n");
+		return -ENOMEM;
 	}
 
-	draw.handle = i * 8 * sizeof(*bitfield) + j + 1;
-	DRM_DEBUG("%d\n", draw.handle);
-
 	spin_lock_irqsave(&dev->drw_lock, irqflags);
-
-	bitfield[i] |= 1 << j;
-	info[draw.handle - 1] = NULL;
-
-	if (bitfield != dev->drw_bitfield) {
-		memcpy(bitfield, dev->drw_bitfield, dev->drw_bitfield_length *
-		       sizeof(*bitfield));
-		drm_free(dev->drw_bitfield, sizeof(*bitfield) *
-			 dev->drw_bitfield_length, DRM_MEM_BUFS);
-		dev->drw_bitfield = bitfield;
-		dev->drw_bitfield_length = bitfield_length;
-	}
-
-	if (info != dev->drw_info) {
-		memcpy(info, dev->drw_info, dev->drw_info_length *
-		       sizeof(*info));
-		drm_free(dev->drw_info, sizeof(*info) * dev->drw_info_length,
-			 DRM_MEM_BUFS);
-		dev->drw_info = info;
-		dev->drw_info_length = info_length;
+	ret = idr_get_new_above(&dev->drw_idr, NULL, 1, &new_id);
+	if (ret == -EAGAIN) {
+		spin_unlock_irqrestore(&dev->drw_lock, irqflags);
+		goto again;
 	}
 
 	spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 
+	draw.handle = new_id;
+
+	DRM_DEBUG("%d\n", draw.handle);
+
 	DRM_COPY_TO_USER_IOCTL((struct drm_draw __user *)data, draw, sizeof(draw));
 
 	return 0;
@@ -132,133 +79,44 @@ int drm_rmdraw(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	struct drm_draw draw;
- 	int id, idx;
- 	unsigned int shift;
 	unsigned long irqflags;
-	u32 *bitfield = dev->drw_bitfield;
-	unsigned int bitfield_length = dev->drw_bitfield_length;
-	struct drm_drawable_info **info = dev->drw_info;
-	unsigned int info_length = dev->drw_info_length;
 
 	DRM_COPY_FROM_USER_IOCTL(draw, (struct drm_draw __user *) data,
 				 sizeof(draw));
 
-	id = draw.handle - 1;
-	idx = id / (8 * sizeof(*bitfield));
-	shift = id % (8 * sizeof(*bitfield));
-
-	if (idx < 0 || idx >= bitfield_length ||
-	    !(bitfield[idx] & (1 << shift))) {
-		DRM_DEBUG("No such drawable %d\n", draw.handle);
-		return 0;
-	}
-
 	spin_lock_irqsave(&dev->drw_lock, irqflags);
 
-	bitfield[idx] &= ~(1 << shift);
-
-	spin_unlock_irqrestore(&dev->drw_lock, irqflags);
-
-	if (info[id]) {
-		drm_free(info[id]->rects, info[id]->num_rects *
-			 sizeof(struct drm_clip_rect), DRM_MEM_BUFS);
-		drm_free(info[id], sizeof(**info), DRM_MEM_BUFS);
-	}
-
-	/* Can we shrink the arrays? */
-	if (idx == bitfield_length - 1) {
-		while (idx >= 0 && !bitfield[idx])
-			--idx;
-
-		bitfield_length = idx + 1;
-
-		bitfield = NULL;
-
-		if (bitfield_length) {
-			if (bitfield_length != dev->drw_bitfield_length)
-				bitfield = drm_alloc(bitfield_length *
-						     sizeof(*bitfield),
-						     DRM_MEM_BUFS);
-
-			if (!bitfield) {
-				bitfield = dev->drw_bitfield;
-				bitfield_length = dev->drw_bitfield_length;
-			}
-		}
-	}
-
-	if (bitfield != dev->drw_bitfield) {
-		info_length = 8 * sizeof(*bitfield) * bitfield_length;
-
-		if (info_length) {
-			info = drm_alloc(info_length * sizeof(*info),
-					 DRM_MEM_BUFS);
-
-			if (!info) {
-				info = dev->drw_info;
-				info_length = dev->drw_info_length;
-			}
-		} else
-			info = NULL;
-
-		spin_lock_irqsave(&dev->drw_lock, irqflags);
-
-		if (bitfield)
-			memcpy(bitfield, dev->drw_bitfield, bitfield_length *
-			       sizeof(*bitfield));
-		drm_free(dev->drw_bitfield, sizeof(*bitfield) *
-			 dev->drw_bitfield_length, DRM_MEM_BUFS);
-		dev->drw_bitfield = bitfield;
-		dev->drw_bitfield_length = bitfield_length;
-
-		if (info != dev->drw_info) {
-			if (info)
-				memcpy(info, dev->drw_info, info_length *
-				       sizeof(*info));
-			drm_free(dev->drw_info, sizeof(*info) *
-				 dev->drw_info_length, DRM_MEM_BUFS);
-			dev->drw_info = info;
-			dev->drw_info_length = info_length;
-		}
+	drm_free(drm_get_drawable_info(dev, draw.handle),
+		 sizeof(struct drm_drawable_info), DRM_MEM_BUFS);
 
-		spin_unlock_irqrestore(&dev->drw_lock, irqflags);
-	}
+	idr_remove(&dev->drw_idr, draw.handle);
 
+	spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 	DRM_DEBUG("%d\n", draw.handle);
 	return 0;
 }
 
-int drm_update_drawable_info(DRM_IOCTL_ARGS) {
+int drm_update_drawable_info(DRM_IOCTL_ARGS)
+{
 	DRM_DEVICE;
 	struct drm_update_draw update;
-	unsigned int id, idx, shift;
-	u32 *bitfield = dev->drw_bitfield;
-	unsigned long irqflags, bitfield_length = dev->drw_bitfield_length;
-	struct drm_drawable_info *info;
+	unsigned long irqflags;
 	struct drm_clip_rect *rects;
+	struct drm_drawable_info *info;
 	int err;
 
 	DRM_COPY_FROM_USER_IOCTL(update, (struct drm_update_draw __user *) data,
 				 sizeof(update));
 
-	id = update.handle - 1;
-	idx = id / (8 * sizeof(*bitfield));
-	shift = id % (8 * sizeof(*bitfield));
-
-	if (idx < 0 || idx >= bitfield_length ||
-	    !(bitfield[idx] & (1 << shift))) {
-		DRM_ERROR("No such drawable %d\n", update.handle);
-		return DRM_ERR(EINVAL);
-	}
-
-	info = dev->drw_info[id];
-
+	info = idr_find(&dev->drw_idr, update.handle);
 	if (!info) {
-		info = drm_calloc(1, sizeof(struct drm_drawable_info), DRM_MEM_BUFS);
-
-		if (!info) {
-			DRM_ERROR("Failed to allocate drawable info memory\n");
-			return DRM_ERR(ENOMEM);
+		info = drm_calloc(1, sizeof(*info), DRM_MEM_BUFS);
+		if (!info)
+			return -ENOMEM;
+		if (IS_ERR(idr_replace(&dev->drw_idr, info, update.handle))) {
+			DRM_ERROR("No such drawable %d\n", update.handle);
+			drm_free(info, sizeof(*info), DRM_MEM_BUFS);
+			return -EINVAL;
 		}
 	}
 
@@ -295,12 +153,11 @@ int drm_update_drawable_info(DRM_IOCTL_ARGS) {
 
 		info->rects = rects;
 		info->num_rects = update.num;
-		dev->drw_info[id] = info;
 
 		spin_unlock_irqrestore(&dev->drw_lock, irqflags);
 
 		DRM_DEBUG("Updated %d cliprects for drawable %d\n",
-			  info->num_rects, id);
+			  info->num_rects, update.handle);
 		break;
 	default:
 		DRM_ERROR("Invalid update type %d\n", update.type);
@@ -310,11 +167,9 @@ int drm_update_drawable_info(DRM_IOCTL_ARGS) {
 	return 0;
 
 error:
-	if (!dev->drw_info[id])
-		drm_free(info, sizeof(*info), DRM_MEM_BUFS);
-	else if (rects != dev->drw_info[id]->rects)
-		drm_free(rects, update.num *
-			 sizeof(struct drm_clip_rect), DRM_MEM_BUFS);
+	if (rects != info->rects)
+		drm_free(rects, update.num * sizeof(struct drm_clip_rect),
+			 DRM_MEM_BUFS);
 
 	return err;
 }
@@ -322,20 +177,27 @@ error:
 /**
  * Caller must hold the drawable spinlock!
  */
-struct drm_drawable_info *drm_get_drawable_info(struct drm_device *dev, drm_drawable_t id) {
-	u32 *bitfield = dev->drw_bitfield;
-	unsigned int idx, shift;
-
-	id--;
-	idx = id / (8 * sizeof(*bitfield));
-	shift = id % (8 * sizeof(*bitfield));
-
-	if (idx < 0 || idx >= dev->drw_bitfield_length ||
-	    !(bitfield[idx] & (1 << shift))) {
-		DRM_DEBUG("No such drawable %d\n", id);
-		return NULL;
+struct drm_drawable_info *drm_get_drawable_info(struct drm_device *dev, drm_drawable_t id)
+{
+	return idr_find(&dev->drw_idr, id);
+}
+EXPORT_SYMBOL(drm_get_drawable_info);
+
+static int drm_drawable_free(int idr, void *p, void *data)
+{
+	struct drm_drawable_info *info = p;
+
+	if (info) {
+		drm_free(info->rects, info->num_rects *
+			 sizeof(struct drm_clip_rect), DRM_MEM_BUFS);
+		drm_free(info, sizeof(*info), DRM_MEM_BUFS);
 	}
 
-	return dev->drw_info[id];
+	return 0;
+}
+
+void drm_drawable_free_all(struct drm_device *dev)
+{
+	idr_for_each(&dev->drw_idr, drm_drawable_free, NULL);
+	idr_remove_all(&dev->drw_idr);
 }
-EXPORT_SYMBOL(drm_get_drawable_info);

drivers/char/drm/drm_drv.c

@@ -151,19 +151,10 @@ int drm_lastclose(struct drm_device * dev)
 	if (dev->irq_enabled)
 		drm_irq_uninstall(dev);
 
-	/* Free drawable information memory */
-	for (i = 0; i < dev->drw_bitfield_length / sizeof(*dev->drw_bitfield);
-	     i++) {
-		struct drm_drawable_info *info = drm_get_drawable_info(dev, i);
-
-		if (info) {
-			drm_free(info->rects, info->num_rects *
-				 sizeof(struct drm_clip_rect), DRM_MEM_BUFS);
-			drm_free(info, sizeof(*info), DRM_MEM_BUFS);
-		}
-	}
-
 	mutex_lock(&dev->struct_mutex);
+
+	/* Free drawable information memory */
+	drm_drawable_free_all(dev);
 	del_timer(&dev->timer);
 
 	/* Clear pid list */