From: Guangming Cao Date: Thu, 14 Oct 2021 10:25:51 +0000 (+0800) Subject: dma-buf: remove restriction of IOCTL:DMA_BUF_SET_NAME X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e73c317efbf9a6ab2d1c18eff8343958ab6df73a;p=linux.git dma-buf: remove restriction of IOCTL:DMA_BUF_SET_NAME In this patch(https://patchwork.freedesktop.org/patch/310349), it add a new IOCTL to support dma-buf user to set debug name. But it also added a limitation of this IOCTL, it needs the attachments of dmabuf should be empty, otherwise it will fail. For the original series, the idea was that allowing name change mid-use could confuse the users about the dma-buf. However, the rest of the series also makes sure each dma-buf have a unique inode(https://patchwork.freedesktop.org/patch/310387/), and any accounting should probably use that, without relying on the name as much. So, removing this restriction will let dma-buf userspace users to use it more comfortably and without any side effect. Signed-off-by: Guangming Cao Link: https://patchwork.freedesktop.org/patch/msgid/20211014102551.54983-1-guangming.cao@mediatek.com Reviewed-by: Christian König Signed-off-by: Christian König --- diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 7b619998f03a0..3f63d58bf68ad 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -293,10 +293,8 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll) /** * dma_buf_set_name - Set a name to a specific dma_buf to track the usage. - * The name of the dma-buf buffer can only be set when the dma-buf is not - * attached to any devices. It could theoritically support changing the - * name of the dma-buf if the same piece of memory is used for multiple - * purpose between different devices. + * It could support changing the name of the dma-buf if the same + * piece of memory is used for multiple purpose between different devices. * * @dmabuf: [in] dmabuf buffer that will be renamed. * @buf: [in] A piece of userspace memory that contains the name of @@ -309,25 +307,16 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll) static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf) { char *name = strndup_user(buf, DMA_BUF_NAME_LEN); - long ret = 0; if (IS_ERR(name)) return PTR_ERR(name); - dma_resv_lock(dmabuf->resv, NULL); - if (!list_empty(&dmabuf->attachments)) { - ret = -EBUSY; - kfree(name); - goto out_unlock; - } spin_lock(&dmabuf->name_lock); kfree(dmabuf->name); dmabuf->name = name; spin_unlock(&dmabuf->name_lock); -out_unlock: - dma_resv_unlock(dmabuf->resv); - return ret; + return 0; } static long dma_buf_ioctl(struct file *file,