[PATCH 16/48] staging: etnaviv: give etnaviv_gem_mmap_offset() a sane behaviour

[Lucas Stach]

From: Russell King <rmk+ker...@arm.linux.org.uk>

etnaviv_gem_mmap_offset() returned zero if drm_gem_create_mmap_offset()
failed.  This is incorrect behaviour as etnaviv_ioctl_gem_info() does
not detect this condition, so it returns success.

Fix this by re-architecting etnaviv_gem_mmap_offset().  Merge
mmap_offset() into this function, and change its prototype to accept a
pointer to the "offset" return value, thereby allowing it to return a
standard negative errno code.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
 drivers/staging/etnaviv/etnaviv_drv.c |  4 ++--
 drivers/staging/etnaviv/etnaviv_drv.h |  2 +-
 drivers/staging/etnaviv/etnaviv_gem.c | 26 +++++++-------------------
 3 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/drivers/staging/etnaviv/etnaviv_drv.c 
b/drivers/staging/etnaviv/etnaviv_drv.c
index 1071c449f3d4..9962318075c5 100644
--- a/drivers/staging/etnaviv/etnaviv_drv.c
+++ b/drivers/staging/etnaviv/etnaviv_drv.c
@@ -438,7 +438,7 @@ static int etnaviv_ioctl_gem_info(struct drm_device *dev, 
void *data,
 {
        struct drm_etnaviv_gem_info *args = data;
        struct drm_gem_object *obj;
-       int ret = 0;
+       int ret;

        if (args->pad)
                return -EINVAL;
@@ -447,7 +447,7 @@ static int etnaviv_ioctl_gem_info(struct drm_device *dev, 
void *data,
        if (!obj)
                return -ENOENT;

-       args->offset = etnaviv_gem_mmap_offset(obj);
+       ret = etnaviv_gem_mmap_offset(obj, &args->offset);

        drm_gem_object_unreference_unlocked(obj);

diff --git a/drivers/staging/etnaviv/etnaviv_drv.h 
b/drivers/staging/etnaviv/etnaviv_drv.h
index 9abb7f8c2dc0..37992342bbf0 100644
--- a/drivers/staging/etnaviv/etnaviv_drv.h
+++ b/drivers/staging/etnaviv/etnaviv_drv.h
@@ -73,7 +73,7 @@ int etnaviv_ioctl_gem_submit(struct drm_device *dev, void 
*data,

 int etnaviv_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 int etnaviv_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
-uint64_t etnaviv_gem_mmap_offset(struct drm_gem_object *obj);
+int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, uint64_t *offset);
 int etnaviv_gem_get_iova_locked(struct etnaviv_gpu *gpu,
        struct drm_gem_object *obj, uint32_t *iova);
 int etnaviv_gem_get_iova(struct etnaviv_gpu *gpu, struct drm_gem_object *obj,
diff --git a/drivers/staging/etnaviv/etnaviv_gem.c 
b/drivers/staging/etnaviv/etnaviv_gem.c
index 522e5a6c3612..38dee80d996c 100644
--- a/drivers/staging/etnaviv/etnaviv_gem.c
+++ b/drivers/staging/etnaviv/etnaviv_gem.c
@@ -270,33 +270,21 @@ out:
 }

 /** get mmap offset */
-static uint64_t mmap_offset(struct drm_gem_object *obj)
+int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, uint64_t *offset)
 {
        struct drm_device *dev = obj->dev;
        int ret;

-       WARN_ON(!mutex_is_locked(&dev->struct_mutex));
-
+       mutex_lock(&dev->struct_mutex);
        /* Make it mmapable */
        ret = drm_gem_create_mmap_offset(obj);
-
-       if (ret) {
+       if (ret)
                dev_err(dev->dev, "could not allocate mmap offset\n");
-               return 0;
-       }
-
-       return drm_vma_node_offset_addr(&obj->vma_node);
-}
-
-uint64_t etnaviv_gem_mmap_offset(struct drm_gem_object *obj)
-{
-       uint64_t offset;
-
-       mutex_lock(&obj->dev->struct_mutex);
-       offset = mmap_offset(obj);
-       mutex_unlock(&obj->dev->struct_mutex);
+       else
+               *offset = drm_vma_node_offset_addr(&obj->vma_node);
+       mutex_unlock(&dev->struct_mutex);

-       return offset;
+       return ret;
 }

 /* should be called under struct_mutex.. although it can be called
-- 
2.5.1