drm/nouveau: Add unlocked variants of nouveau_channel_get/put.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_channel.c b/drivers/gpu/drm/nouveau/nouveau_channel.c
index c46a6f6..38929fd 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_channel.c
+++ b/drivers/gpu/drm/nouveau/nouveau_channel.c
@@ -238,33 +238,39 @@ nouveau_channel_alloc(struct drm_device *dev, struct nouveau_channel **chan_ret,
 }
 
 struct nouveau_channel *
+nouveau_channel_get_unlocked(struct nouveau_channel *ref)
+{
+       if (likely(ref && atomic_inc_not_zero(&ref->refcount)))
+               return ref;
+
+       return NULL;
+}
+
+struct nouveau_channel *
 nouveau_channel_get(struct drm_device *dev, struct drm_file *file_priv, int id)
 {
        struct drm_nouveau_private *dev_priv = dev->dev_private;
-       struct nouveau_channel *chan = ERR_PTR(-ENODEV);
+       struct nouveau_channel *chan;
        unsigned long flags;
 
        spin_lock_irqsave(&dev_priv->channels.lock, flags);
-       chan = dev_priv->channels.ptr[id];
+       chan = nouveau_channel_get_unlocked(dev_priv->channels.ptr[id]);
+       spin_unlock_irqrestore(&dev_priv->channels.lock, flags);
 
-       if (unlikely(!chan || (file_priv && chan->file_priv != file_priv))) {
-               spin_unlock_irqrestore(&dev_priv->channels.lock, flags);
+       if (unlikely(!chan))
                return ERR_PTR(-EINVAL);
-       }
 
-       if (unlikely(!atomic_inc_not_zero(&chan->refcount))) {
-               spin_unlock_irqrestore(&dev_priv->channels.lock, flags);
+       if (unlikely(file_priv && chan->file_priv != file_priv)) {
+               nouveau_channel_put_unlocked(&chan);
                return ERR_PTR(-EINVAL);
        }
 
-       spin_unlock_irqrestore(&dev_priv->channels.lock, flags);
-
        mutex_lock(&chan->mutex);
        return chan;
 }
 
 void
-nouveau_channel_put(struct nouveau_channel **pchan)
+nouveau_channel_put_unlocked(struct nouveau_channel **pchan)
 {
        struct nouveau_channel *chan = *pchan;
        struct drm_device *dev = chan->dev;
@@ -274,9 +280,6 @@ nouveau_channel_put(struct nouveau_channel **pchan)
        unsigned long flags;
        int ret;
 
-       /* unlock the channel */
-       mutex_unlock(&chan->mutex);
-
        /* decrement the refcount, and we're done if there's still refs */
        if (likely(!atomic_dec_and_test(&chan->refcount))) {
                *pchan = NULL;
@@ -348,6 +351,13 @@ nouveau_channel_put(struct nouveau_channel **pchan)
        kfree(chan);
 }
 
+void
+nouveau_channel_put(struct nouveau_channel **pchan)
+{
+       mutex_unlock(&(*pchan)->mutex);
+       nouveau_channel_put_unlocked(pchan);
+}
+
 /* cleans up all the fifos from file_priv */
 void
 nouveau_channel_cleanup(struct drm_device *dev, struct drm_file *file_priv)

diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 198dabe..e6708be 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -803,7 +803,10 @@ extern int  nouveau_channel_alloc(struct drm_device *dev,
                                  struct drm_file *file_priv,
                                  uint32_t fb_ctxdma, uint32_t tt_ctxdma);
 extern struct nouveau_channel *
+nouveau_channel_get_unlocked(struct nouveau_channel *);
+extern struct nouveau_channel *
 nouveau_channel_get(struct drm_device *, struct drm_file *, int id);
+extern void nouveau_channel_put_unlocked(struct nouveau_channel **);
 extern void nouveau_channel_put(struct nouveau_channel **);
 
 /* nouveau_object.c */