From 56e5abba8c3ec5c6098007693f9cefafaa2aa010 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Mon, 17 Oct 2022 20:22:09 +0300 Subject: dma-buf: Add unlocked variant of vmapping functions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add unlocked variant of dma_buf_vmap/vunmap() that will be utilized by drivers that don't take the reservation lock explicitly. Acked-by: Sumit Semwal Acked-by: Christian König Signed-off-by: Dmitry Osipenko Link: https://patchwork.freedesktop.org/patch/msgid/20221017172229.42269-2-dmitry.osipenko@collabora.com --- include/linux/dma-buf.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 71731796c8c3..8daa054dd7fe 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -632,4 +632,6 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map); void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map); +int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map); +void dma_buf_vunmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map); #endif /* __DMA_BUF_H__ */ -- cgit v1.2.3 From 19d6634d8789573a9212ce78dbb4348ffd4f7f78 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Mon, 17 Oct 2022 20:22:10 +0300 Subject: dma-buf: Add unlocked variant of attachment-mapping functions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add unlocked variant of dma_buf_map/unmap_attachment() that will be used by drivers that don't take the reservation lock explicitly. Acked-by: Sumit Semwal Acked-by: Christian König Signed-off-by: Dmitry Osipenko Link: https://patchwork.freedesktop.org/patch/msgid/20221017172229.42269-3-dmitry.osipenko@collabora.com --- drivers/dma-buf/dma-buf.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 6 ++++++ 2 files changed, 59 insertions(+) (limited to 'include/linux') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index e95fc8dc3aed..3e4060dadb74 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1100,6 +1100,34 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, } EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment, DMA_BUF); +/** + * dma_buf_map_attachment_unlocked - Returns the scatterlist table of the attachment; + * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the + * dma_buf_ops. + * @attach: [in] attachment whose scatterlist is to be returned + * @direction: [in] direction of DMA transfer + * + * Unlocked variant of dma_buf_map_attachment(). + */ +struct sg_table * +dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach, + enum dma_data_direction direction) +{ + struct sg_table *sg_table; + + might_sleep(); + + if (WARN_ON(!attach || !attach->dmabuf)) + return ERR_PTR(-EINVAL); + + dma_resv_lock(attach->dmabuf->resv, NULL); + sg_table = dma_buf_map_attachment(attach, direction); + dma_resv_unlock(attach->dmabuf->resv); + + return sg_table; +} +EXPORT_SYMBOL_NS_GPL(dma_buf_map_attachment_unlocked, DMA_BUF); + /** * dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of @@ -1136,6 +1164,31 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, } EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment, DMA_BUF); +/** + * dma_buf_unmap_attachment_unlocked - unmaps and decreases usecount of the buffer;might + * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of + * dma_buf_ops. + * @attach: [in] attachment to unmap buffer from + * @sg_table: [in] scatterlist info of the buffer to unmap + * @direction: [in] direction of DMA transfer + * + * Unlocked variant of dma_buf_unmap_attachment(). + */ +void dma_buf_unmap_attachment_unlocked(struct dma_buf_attachment *attach, + struct sg_table *sg_table, + enum dma_data_direction direction) +{ + might_sleep(); + + if (WARN_ON(!attach || !attach->dmabuf || !sg_table)) + return; + + dma_resv_lock(attach->dmabuf->resv, NULL); + dma_buf_unmap_attachment(attach, sg_table, direction); + dma_resv_unlock(attach->dmabuf->resv); +} +EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_attachment_unlocked, DMA_BUF); + /** * dma_buf_move_notify - notify attachments that DMA-buf is moving * diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 8daa054dd7fe..f11b5bbc2f37 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -627,6 +627,12 @@ int dma_buf_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction dir); int dma_buf_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction dir); +struct sg_table * +dma_buf_map_attachment_unlocked(struct dma_buf_attachment *attach, + enum dma_data_direction direction); +void dma_buf_unmap_attachment_unlocked(struct dma_buf_attachment *attach, + struct sg_table *sg_table, + enum dma_data_direction direction); int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); -- cgit v1.2.3 From 28743e25fa1c867675bd8ff976eb92d4251f13a1 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Mon, 17 Oct 2022 20:22:29 +0300 Subject: dma-buf: Remove obsoleted internal lock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The internal dma-buf lock isn't needed anymore because the updated locking specification claims that dma-buf reservation must be locked by importers, and thus, the internal data is already protected by the reservation lock. Remove the obsoleted internal lock. Acked-by: Sumit Semwal Acked-by: Christian König Reviewed-by: Christian König Signed-off-by: Dmitry Osipenko Link: https://patchwork.freedesktop.org/patch/msgid/20221017172229.42269-22-dmitry.osipenko@collabora.com --- drivers/dma-buf/dma-buf.c | 14 ++++---------- include/linux/dma-buf.h | 9 --------- 2 files changed, 4 insertions(+), 19 deletions(-) (limited to 'include/linux') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index f1d968e5bac4..7663c4e784b6 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -657,7 +657,6 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) dmabuf->file = file; - mutex_init(&dmabuf->lock); INIT_LIST_HEAD(&dmabuf->attachments); mutex_lock(&db_list.lock); @@ -1503,7 +1502,7 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF); int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map) { struct iosys_map ptr; - int ret = 0; + int ret; iosys_map_clear(map); @@ -1515,28 +1514,25 @@ int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map) if (!dmabuf->ops->vmap) return -EINVAL; - mutex_lock(&dmabuf->lock); if (dmabuf->vmapping_counter) { dmabuf->vmapping_counter++; BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr)); *map = dmabuf->vmap_ptr; - goto out_unlock; + return 0; } BUG_ON(iosys_map_is_set(&dmabuf->vmap_ptr)); ret = dmabuf->ops->vmap(dmabuf, &ptr); if (WARN_ON_ONCE(ret)) - goto out_unlock; + return ret; dmabuf->vmap_ptr = ptr; dmabuf->vmapping_counter = 1; *map = dmabuf->vmap_ptr; -out_unlock: - mutex_unlock(&dmabuf->lock); - return ret; + return 0; } EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF); @@ -1583,13 +1579,11 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) BUG_ON(dmabuf->vmapping_counter == 0); BUG_ON(!iosys_map_is_equal(&dmabuf->vmap_ptr, map)); - mutex_lock(&dmabuf->lock); if (--dmabuf->vmapping_counter == 0) { if (dmabuf->ops->vunmap) dmabuf->ops->vunmap(dmabuf, map); iosys_map_clear(&dmabuf->vmap_ptr); } - mutex_unlock(&dmabuf->lock); } EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF); diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index f11b5bbc2f37..6fa8d4e29719 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -326,15 +326,6 @@ struct dma_buf { /** @ops: dma_buf_ops associated with this buffer object. */ const struct dma_buf_ops *ops; - /** - * @lock: - * - * Used internally to serialize list manipulation, attach/detach and - * vmap/unmap. Note that in many cases this is superseeded by - * dma_resv_lock() on @resv. - */ - struct mutex lock; - /** * @vmapping_counter: * -- cgit v1.2.3