diff --git a/Documentation/driver-api/dmaengine/client.rst b/Documentation/driver-api/dmaengine/client.rst index a9a7a3c84c63..e5953e7e4bf4 100644 --- a/Documentation/driver-api/dmaengine/client.rst +++ b/Documentation/driver-api/dmaengine/client.rst @@ -151,8 +151,8 @@ The details of these operations are: Note that callbacks will always be invoked from the DMA engines tasklet, never from interrupt context. - Optional: per descriptor metadata - --------------------------------- +Optional: per descriptor metadata +--------------------------------- DMAengine provides two ways for metadata support. DESC_METADATA_CLIENT diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index f3ef4edd4de1..c3b1283b6d31 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -756,22 +756,21 @@ struct dma_chan *dma_request_chan(struct device *dev, const char *name) } mutex_unlock(&dma_list_mutex); - if (!IS_ERR_OR_NULL(chan)) - goto found; - - return ERR_PTR(-EPROBE_DEFER); + if (IS_ERR_OR_NULL(chan)) + return chan ? chan : ERR_PTR(-EPROBE_DEFER); found: - chan->slave = dev; chan->name = kasprintf(GFP_KERNEL, "dma:%s", name); if (!chan->name) - return ERR_PTR(-ENOMEM); + return chan; + chan->slave = dev; if (sysfs_create_link(&chan->dev->device.kobj, &dev->kobj, DMA_SLAVE_NAME)) - dev_err(dev, "Cannot create DMA %s symlink\n", DMA_SLAVE_NAME); + dev_warn(dev, "Cannot create DMA %s symlink\n", DMA_SLAVE_NAME); if (sysfs_create_link(&dev->kobj, &chan->dev->device.kobj, chan->name)) - dev_err(dev, "Cannot create DMA %s symlink\n", chan->name); + dev_warn(dev, "Cannot create DMA %s symlink\n", chan->name); + return chan; } EXPORT_SYMBOL_GPL(dma_request_chan); @@ -830,13 +829,14 @@ void dma_release_channel(struct dma_chan *chan) /* drop PRIVATE cap enabled by __dma_request_channel() */ if (--chan->device->privatecnt == 0) dma_cap_clear(DMA_PRIVATE, chan->device->cap_mask); + if (chan->slave) { + sysfs_remove_link(&chan->dev->device.kobj, DMA_SLAVE_NAME); sysfs_remove_link(&chan->slave->kobj, chan->name); kfree(chan->name); chan->name = NULL; chan->slave = NULL; } - sysfs_remove_link(&chan->dev->device.kobj, DMA_SLAVE_NAME); mutex_unlock(&dma_list_mutex); } EXPORT_SYMBOL_GPL(dma_release_channel); @@ -962,6 +962,9 @@ static int __dma_async_device_channel_register(struct dma_device *device, tchan = list_first_entry_or_null(&device->channels, struct dma_chan, device_node); + if (!tchan) + return -ENODEV; + if (tchan->dev) { idr_ref = tchan->dev->idr_ref; } else { diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c index 849c50ab939a..6d907fe150aa 100644 --- a/drivers/dma/idxd/sysfs.c +++ b/drivers/dma/idxd/sysfs.c @@ -66,7 +66,7 @@ static inline bool is_idxd_wq_dmaengine(struct idxd_wq *wq) static inline bool is_idxd_wq_cdev(struct idxd_wq *wq) { - return wq->type == IDXD_WQT_USER ? true : false; + return wq->type == IDXD_WQT_USER; } static int idxd_config_bus_match(struct device *dev,