[PATCH v17 11/18] drm/shmem-helper: Improve drm_gem_shmem_vmap_locked() error handling

From: Dmitry Osipenko
Date: Thu Sep 14 2023 - 19:29:35 EST


Remove error unwinding from drm_gem_shmem_vmap_locked() making error
paths consistent for both dmabuf and non-dmabuf cases and improving
readability of the code. Often it's preferred to do the explicit error
unwinding, but this multi-path function is an exception.

Suggested-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_gem_shmem_helper.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
index e1fcb5154209..8a8eab4d0332 100644
--- a/drivers/gpu/drm/drm_gem_shmem_helper.c
+++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
@@ -334,7 +334,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
struct iosys_map *map)
{
struct drm_gem_object *obj = &shmem->base;
- int ret = 0;
+ int ret;

if (obj->import_attach) {
ret = dma_buf_vmap(obj->import_attach->dmabuf, map);
@@ -357,6 +357,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
shmem->vaddr = vmap(shmem->pages, obj->size >> PAGE_SHIFT,
VM_MAP, prot);
if (!shmem->vaddr) {
+ drm_gem_shmem_unpin_locked(shmem);
ret = -ENOMEM;
} else {
iosys_map_set_vaddr(map, shmem->vaddr);
@@ -364,16 +365,8 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
}
}

- if (ret) {
+ if (ret)
drm_dbg_kms(obj->dev, "Failed to vmap pages, error %d\n", ret);
- goto err_put_pages;
- }
-
- return 0;
-
-err_put_pages:
- if (!obj->import_attach)
- drm_gem_shmem_unpin_locked(shmem);

return ret;
}
--
2.41.0