[media] vb2: convert vb2_vmarea_handler refcount from atomic_t to refcount_t

Use refcount_t to manage the refcount to the memory type specific buffer
videobuf2 buffer implementations. refcount_t is better suitable for the
purpose than atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index fb6a177be46191012c7b88a09b5ab8446efed18b..d29a07f3b04853c021dc30ba6517fcca7f7d52e2 100644 (file)
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -12,6 +12,7 @@
 
 #include <linux/dma-buf.h>
 #include <linux/module.h>
+#include <linux/refcount.h>
 #include <linux/scatterlist.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -34,7 +35,7 @@ struct vb2_dc_buf {
 
        /* MMAP related */
        struct vb2_vmarea_handler       handler;
-       atomic_t                        refcount;
+       refcount_t                      refcount;
        struct sg_table                 *sgt_base;
 
        /* DMABUF related */
@@ -86,7 +87,7 @@ static unsigned int vb2_dc_num_users(void *buf_priv)
 {
        struct vb2_dc_buf *buf = buf_priv;
 
-       return atomic_read(&buf->refcount);
+       return refcount_read(&buf->refcount);
 }
 
 static void vb2_dc_prepare(void *buf_priv)
@@ -122,7 +123,7 @@ static void vb2_dc_put(void *buf_priv)
 {
        struct vb2_dc_buf *buf = buf_priv;
 
-       if (!atomic_dec_and_test(&buf->refcount))
+       if (!refcount_dec_and_test(&buf->refcount))
                return;
 
        if (buf->sgt_base) {
@@ -170,7 +171,7 @@ static void *vb2_dc_alloc(struct device *dev, unsigned long attrs,
        buf->handler.put = vb2_dc_put;
        buf->handler.arg = buf;
 
-       atomic_inc(&buf->refcount);
+       refcount_set(&buf->refcount, 1);
 
        return buf;
 }
@@ -407,7 +408,7 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags)
                return NULL;
 
        /* dmabuf keeps reference to vb2 buffer */
-       atomic_inc(&buf->refcount);
+       refcount_inc(&buf->refcount);
 
        return dbuf;
 }

diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index ecff8f492c4ff8cdfdaf14bb5b907e8aa1ad5f9e..29fde1a58a790afb65774ab785d950cfcac00f50 100644 (file)
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -12,6 +12,7 @@
 
 #include <linux/module.h>
 #include <linux/mm.h>
+#include <linux/refcount.h>
 #include <linux/scatterlist.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -46,7 +47,7 @@ struct vb2_dma_sg_buf {
        struct sg_table                 *dma_sgt;
        size_t                          size;
        unsigned int                    num_pages;
-       atomic_t                        refcount;
+       refcount_t                      refcount;
        struct vb2_vmarea_handler       handler;
 
        struct dma_buf_attachment       *db_attach;
@@ -150,7 +151,7 @@ static void *vb2_dma_sg_alloc(struct device *dev, unsigned long dma_attrs,
        buf->handler.put = vb2_dma_sg_put;
        buf->handler.arg = buf;
 
-       atomic_inc(&buf->refcount);
+       refcount_set(&buf->refcount, 1);
 
        dprintk(1, "%s: Allocated buffer of %d pages\n",
                __func__, buf->num_pages);
@@ -176,7 +177,7 @@ static void vb2_dma_sg_put(void *buf_priv)
        struct sg_table *sgt = &buf->sg_table;
        int i = buf->num_pages;
 
-       if (atomic_dec_and_test(&buf->refcount)) {
+       if (refcount_dec_and_test(&buf->refcount)) {
                dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
                        buf->num_pages);
                dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
@@ -320,7 +321,7 @@ static unsigned int vb2_dma_sg_num_users(void *buf_priv)
 {
        struct vb2_dma_sg_buf *buf = buf_priv;
 
-       return atomic_read(&buf->refcount);
+       return refcount_read(&buf->refcount);
 }
 
 static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma)
@@ -530,7 +531,7 @@ static struct dma_buf *vb2_dma_sg_get_dmabuf(void *buf_priv, unsigned long flags
                return NULL;
 
        /* dmabuf keeps reference to vb2 buffer */
-       atomic_inc(&buf->refcount);
+       refcount_inc(&buf->refcount);
 
        return dbuf;
 }

diff --git a/drivers/media/v4l2-core/videobuf2-memops.c b/drivers/media/v4l2-core/videobuf2-memops.c
index 1cd322e939c70520e9e915575590bf516c0e46ee..4bb8424114ce6d12e34d28b1620a1fafeeafa5ca 100644 (file)
--- a/drivers/media/v4l2-core/videobuf2-memops.c
+++ b/drivers/media/v4l2-core/videobuf2-memops.c
@@ -96,10 +96,10 @@ static void vb2_common_vm_open(struct vm_area_struct *vma)
        struct vb2_vmarea_handler *h = vma->vm_private_data;
 
        pr_debug("%s: %p, refcount: %d, vma: %08lx-%08lx\n",
-              __func__, h, atomic_read(h->refcount), vma->vm_start,
+              __func__, h, refcount_read(h->refcount), vma->vm_start,
               vma->vm_end);
 
-       atomic_inc(h->refcount);
+       refcount_inc(h->refcount);
 }
 
 /**
@@ -114,7 +114,7 @@ static void vb2_common_vm_close(struct vm_area_struct *vma)
        struct vb2_vmarea_handler *h = vma->vm_private_data;
 
        pr_debug("%s: %p, refcount: %d, vma: %08lx-%08lx\n",
-              __func__, h, atomic_read(h->refcount), vma->vm_start,
+              __func__, h, refcount_read(h->refcount), vma->vm_start,
               vma->vm_end);
 
        h->put(h->arg);

diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index 3f778147cdef3e70767cc009ee1ddaee57935a08..f83253a233ca26572a4a69d0e4741ea8020ec9b1 100644 (file)
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -13,6 +13,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/mm.h>
+#include <linux/refcount.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
@@ -26,7 +27,7 @@ struct vb2_vmalloc_buf {
        struct frame_vector             *vec;
        enum dma_data_direction         dma_dir;
        unsigned long                   size;
-       atomic_t                        refcount;
+       refcount_t                      refcount;
        struct vb2_vmarea_handler       handler;
        struct dma_buf                  *dbuf;
 };
@@ -56,7 +57,7 @@ static void *vb2_vmalloc_alloc(struct device *dev, unsigned long attrs,
                return ERR_PTR(-ENOMEM);
        }
 
-       atomic_inc(&buf->refcount);
+       refcount_set(&buf->refcount, 1);
        return buf;
 }
 
@@ -64,7 +65,7 @@ static void vb2_vmalloc_put(void *buf_priv)
 {
        struct vb2_vmalloc_buf *buf = buf_priv;
 
-       if (atomic_dec_and_test(&buf->refcount)) {
+       if (refcount_dec_and_test(&buf->refcount)) {
                vfree(buf->vaddr);
                kfree(buf);
        }
@@ -161,7 +162,7 @@ static void *vb2_vmalloc_vaddr(void *buf_priv)
 static unsigned int vb2_vmalloc_num_users(void *buf_priv)
 {
        struct vb2_vmalloc_buf *buf = buf_priv;
-       return atomic_read(&buf->refcount);
+       return refcount_read(&buf->refcount);
 }
 
 static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma)
@@ -368,7 +369,7 @@ static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flag
                return NULL;
 
        /* dmabuf keeps reference to vb2 buffer */
-       atomic_inc(&buf->refcount);
+       refcount_inc(&buf->refcount);
 
        return dbuf;
 }

diff --git a/include/media/videobuf2-memops.h b/include/media/videobuf2-memops.h
index 36565c7acb542b961fcbe38d8b978a6f802f234c..a6ed091b79ce501a183b2fb6cf6051d169f066f7 100644 (file)
--- a/include/media/videobuf2-memops.h
+++ b/include/media/videobuf2-memops.h
@@ -16,6 +16,7 @@
 
 #include <media/videobuf2-v4l2.h>
 #include <linux/mm.h>
+#include <linux/refcount.h>
 
 /**
  * struct vb2_vmarea_handler - common vma refcount tracking handler
@@ -25,7 +26,7 @@
  * @arg:       argument for @put callback
  */
 struct vb2_vmarea_handler {
-       atomic_t                *refcount;
+       refcount_t              *refcount;
        void                    (*put)(void *arg);
        void                    *arg;
 };