diff options
Diffstat (limited to 'drivers/dma/virt-dma.h')
| -rw-r--r-- | drivers/dma/virt-dma.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h index 3f776a46a29c..b09b75ab0751 100644 --- a/drivers/dma/virt-dma.h +++ b/drivers/dma/virt-dma.h @@ -35,6 +35,7 @@ struct virt_dma_chan { struct list_head desc_completed; struct virt_dma_desc *cyclic; + struct virt_dma_desc *vd_terminated; }; static inline struct virt_dma_chan *to_virt_chan(struct dma_chan *chan) @@ -104,6 +105,20 @@ static inline void vchan_cookie_complete(struct virt_dma_desc *vd) } /** + * vchan_vdesc_fini - Free or reuse a descriptor + * @vd: virtual descriptor to free/reuse + */ +static inline void vchan_vdesc_fini(struct virt_dma_desc *vd) +{ + struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan); + + if (dmaengine_desc_test_reuse(&vd->tx)) + list_add(&vd->node, &vc->desc_allocated); + else + vc->desc_free(vd); +} + +/** * vchan_cyclic_callback - report the completion of a period * @vd: virtual descriptor */ @@ -116,6 +131,25 @@ static inline void vchan_cyclic_callback(struct virt_dma_desc *vd) } /** + * vchan_terminate_vdesc - Disable pending cyclic callback + * @vd: virtual descriptor to be terminated + * + * vc.lock must be held by caller + */ +static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd) +{ + struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan); + + /* free up stuck descriptor */ + if (vc->vd_terminated) + vchan_vdesc_fini(vc->vd_terminated); + + vc->vd_terminated = vd; + if (vc->cyclic == vd) + vc->cyclic = NULL; +} + +/** * vchan_next_desc - peek at the next descriptor to be processed * @vc: virtual channel to obtain descriptor from * @@ -168,10 +202,20 @@ static inline void vchan_free_chan_resources(struct virt_dma_chan *vc) * Makes sure that all scheduled or active callbacks have finished running. For * proper operation the caller has to ensure that no new callbacks are scheduled * after the invocation of this function started. + * Free up the terminated cyclic descriptor to prevent memory leakage. */ static inline void vchan_synchronize(struct virt_dma_chan *vc) { + unsigned long flags; + tasklet_kill(&vc->task); + + spin_lock_irqsave(&vc->lock, flags); + if (vc->vd_terminated) { + vchan_vdesc_fini(vc->vd_terminated); + vc->vd_terminated = NULL; + } + spin_unlock_irqrestore(&vc->lock, flags); } #endif |