[RFC PATCH v1 2/2] dma-buf: add lock callback for fcntl system call

2013-07-12 Thread Inki Dae
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@samsung.com
Signed-off-by: Kyungmin Park kyungmin.p...@samsung.com
---
 drivers/base/dma-buf.c |   33 +
 1 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c
index 9a26981..e1b8583 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,
 };
 
 /*
-- 
1.7.5.4

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[RFC PATCH v1 2/2] dma-buf: add lock callback for fcntl system call.

2013-07-10 Thread Inki Dae
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@samsung.com
Signed-off-by: Kyungmin Park kyungmin.p...@samsung.com
---
 drivers/base/dma-buf.c |   34 ++
 1 files changed, 34 insertions(+), 0 deletions(-)

diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c
index fe39120..cd71447 100644
--- a/drivers/base/dma-buf.c
+++ b/drivers/base/dma-buf.c
@@ -31,6 +31,7 @@
 #include linux/debugfs.h
 #include linux/seq_file.h
 #include linux/reservation.h
+#include linux/dmabuf-sync.h
 
 static inline int is_dma_buf_file(struct file *);
 
@@ -82,9 +83,42 @@ 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,
 };
 
 /*
-- 
1.7.5.4

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