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authorInki Dae <inki.dae@samsung.com>2013-07-12 14:01:02 +0900
committerChanho Park <chanho61.park@samsung.com>2014-11-18 11:43:27 +0900
commit82741c3a6cd13c00b78ba2d9282e6cc000b60b8a (patch)
tree1ca09af22198c432719014828e351919b8088644 /drivers
parent305d1e410b577ed829654fce66a188d259fb630c (diff)
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dma-buf: add lock callback for fcntl system call.
This patch adds lock callback to dma buf file operations, and this callback will be called by fcntl system call. With this patch, fcntl system call can be used for buffer synchronization between CPU and CPU, and CPU and DMA in user mode. Signed-off-by: Inki Dae <inki.dae@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/base/dma-buf.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c
index 9a26981a688..e1b85835030 100644
--- a/drivers/base/dma-buf.c
+++ b/drivers/base/dma-buf.c
@@ -80,9 +80,42 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
return dmabuf->ops->mmap(dmabuf, vma);
}
+static int dma_buf_lock(struct file *file, int cmd, struct file_lock *fl)
+{
+ struct dma_buf *dmabuf;
+ unsigned int type;
+ bool wait = false;
+
+ if (!is_dma_buf_file(file))
+ return -EINVAL;
+
+ dmabuf = file->private_data;
+
+ if ((fl->fl_type & F_UNLCK) == F_UNLCK) {
+ dmabuf_sync_single_unlock(dmabuf);
+ return 0;
+ }
+
+ /* convert flock type to dmabuf sync type. */
+ if ((fl->fl_type & F_WRLCK) == F_WRLCK)
+ type = DMA_BUF_ACCESS_W;
+ else if ((fl->fl_type & F_RDLCK) == F_RDLCK)
+ type = DMA_BUF_ACCESS_R;
+ else
+ return -EINVAL;
+
+ if (fl->fl_flags & FL_SLEEP)
+ wait = true;
+
+ /* TODO. the locking to certain region should also be considered. */
+
+ return dmabuf_sync_single_lock(dmabuf, type, wait);
+}
+
static const struct file_operations dma_buf_fops = {
.release = dma_buf_release,
.mmap = dma_buf_mmap_internal,
+ .lock = dma_buf_lock,
};
/*