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>

3 files changed, 60 insertions, 209 deletions

diff --git a/drivers/char/drm/drmP.h b/drivers/char/drm/drmP.h
index b1cafe36611e..0df87fc3dcb2 100644
--- a/drivers/char/drm/drmP.h
+++ b/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,
diff --git a/drivers/char/drm/drm_drawable.c b/drivers/char/drm/drm_drawable.c
index 309e585a5442..d6cdba5644e2 100644
--- a/drivers/char/drm/drm_drawable.c
+++ b/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);
diff --git a/drivers/char/drm/drm_drv.c b/drivers/char/drm/drm_drv.c
index d5cf5cfccf78..19994cd865de 100644
--- a/drivers/char/drm/drm_drv.c
+++ b/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 */