gpu: nvgpu: fix MISRA violations in utils unit

MISRA rule 11.6 states that a cast shall not be performed between
pointer to void and an arithmetic type.  Fix violations of rule 11.6
in utils unit.

Jira NVGPU-3300

Change-Id: I9513baf326be9618bae9bcfed597bfe27a5a2f47
Signed-off-by: ajesh <akv@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2137305
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/common/mm/vidmem.c

@@ -553,19 +553,24 @@ static int nvgpu_vidmem_clear_all(struct gk20a *g)
 	return 0;
 }
 
-struct nvgpu_vidmem_buf *nvgpu_vidmem_user_alloc(struct gk20a *g, size_t bytes)
+int nvgpu_vidmem_user_alloc(struct gk20a *g, size_t bytes,
+				struct nvgpu_vidmem_buf **vidmem_buf)
 {
 	struct nvgpu_vidmem_buf *buf;
 	int err;
 
+	if (vidmem_buf == NULL) {
+		return -EINVAL;
+	}
+
 	err = nvgpu_vidmem_clear_all(g);
 	if (err != 0) {
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
 
 	buf = nvgpu_kzalloc(g, sizeof(*buf));
 	if (buf == NULL) {
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
 
 	buf->g = g;
@@ -586,13 +591,15 @@ struct nvgpu_vidmem_buf *nvgpu_vidmem_user_alloc(struct gk20a *g, size_t bytes)
 	 */
 	buf->mem->mem_flags |= NVGPU_MEM_FLAG_USER_MEM;
 
-	return buf;
+	*vidmem_buf = buf;
+
+	return 0;
 
 fail:
 	/* buf will never be NULL here. */
 	nvgpu_kfree(g, buf->mem);
 	nvgpu_kfree(g, buf);
-	return ERR_PTR(err);
+	return err;
 }
 
 void nvgpu_vidmem_buf_free(struct gk20a *g, struct nvgpu_vidmem_buf *buf)
@@ -600,7 +607,7 @@ void nvgpu_vidmem_buf_free(struct gk20a *g, struct nvgpu_vidmem_buf *buf)
 	/*
 	 * In some error paths it's convenient to be able to "free" a NULL buf.
 	 */
-	if (IS_ERR_OR_NULL(buf)) {
+	if (buf == NULL) {
 		return;
 	}
 

drivers/gpu/nvgpu/common/vgpu/gr/fecs_trace_vgpu.c

@@ -58,7 +58,8 @@ int vgpu_fecs_trace_init(struct gk20a *g)
 	nvgpu_set_enabled(g, NVGPU_SUPPORT_FECS_CTXSW_TRACE, true);
 
 	vcst->cookie = vgpu_ivm_mempool_reserve(mempool);
-	if (IS_ERR(vcst->cookie)) {
+	if ((vcst->cookie == NULL) ||
+		((unsigned long)vcst->cookie >= (unsigned long)-MAX_ERRNO)) {
 		nvgpu_info(g,
 			"mempool  %u reserve failed", mempool);
 		vcst->cookie = NULL;

drivers/gpu/nvgpu/common/vgpu/perf/cyclestats_snapshot_vgpu.c

@@ -34,30 +34,40 @@
 
 static struct tegra_hv_ivm_cookie *css_cookie;
 
-static struct tegra_hv_ivm_cookie *vgpu_css_reserve_mempool(struct gk20a *g)
+static int vgpu_css_reserve_mempool(struct gk20a *g,
+					struct tegra_hv_ivm_cookie **cookie_p)
 {
 	struct tegra_hv_ivm_cookie *cookie;
 	u32 mempool;
 	int err;
 
+	if (cookie_p == NULL) {
+		return -EINVAL;
+	}
+
 	err = nvgpu_dt_read_u32_index(g, "mempool-css", 1, &mempool);
 	if (err) {
 		nvgpu_err(g, "dt missing mempool-css");
-		return (struct tegra_hv_ivm_cookie *)ERR_PTR(err);
+		return err;
 	}
 
 	cookie = vgpu_ivm_mempool_reserve(mempool);
-	if (IS_ERR_OR_NULL(cookie)) {
+	if ((cookie == NULL) ||
+		((unsigned long)cookie >= (unsigned long)-MAX_ERRNO)) {
 		nvgpu_err(g, "mempool  %u reserve failed", mempool);
-		return (struct tegra_hv_ivm_cookie *)ERR_PTR(-EINVAL);
+		return -EINVAL;
 	}
-	return cookie;
+
+	*cookie_p = cookie;
+
+	return 0;
 }
 
 u32 vgpu_css_get_buffer_size(struct gk20a *g)
 {
 	struct tegra_hv_ivm_cookie *cookie;
 	u32 size;
+	int err;
 
 	nvgpu_log_fn(g, " ");
 
@@ -67,8 +77,8 @@ u32 vgpu_css_get_buffer_size(struct gk20a *g)
 		return size;
 	}
 
-	cookie = vgpu_css_reserve_mempool(g);
-	if (IS_ERR(cookie)) {
+	err = vgpu_css_reserve_mempool(g, &cookie);
+	if (0 != err) {
 		return 0;
 	}
 
@@ -92,9 +102,9 @@ static int vgpu_css_init_snapshot_buffer(struct gk20a *g)
 		return 0;
 	}
 
-	css_cookie = vgpu_css_reserve_mempool(g);
-	if (IS_ERR(css_cookie)) {
-		return PTR_ERR(css_cookie);
+	err = vgpu_css_reserve_mempool(g, &css_cookie);
+	if (0 != err) {
+		return err;
 	}
 
 	size = vgpu_ivm_get_size(css_cookie);

drivers/gpu/nvgpu/hal/gr/gr/gr_gk20a.c

@@ -566,7 +566,7 @@ int gr_gk20a_get_ctx_buffer_offsets(struct gk20a *g,
 
 	*num_offsets = num_registers;
 cleanup:
-	if (!IS_ERR_OR_NULL(priv_registers)) {
+	if (priv_registers != NULL) {
 		nvgpu_kfree(g, priv_registers);
 	}
 

drivers/gpu/nvgpu/include/nvgpu/posix/utils.h

@@ -256,28 +256,6 @@ static inline unsigned int nvgpu_posix_hweight64(uint64_t x)
 
 #define MAX_ERRNO	4095
 
-#define IS_ERR_VALUE(x) ((x) >= (unsigned long)-MAX_ERRNO)
-
-static inline void *ERR_PTR(long error)
-{
-	return (void *) error;
-}
-
-static inline long PTR_ERR(void *error)
-{
-	return (long)(uintptr_t)error;
-}
-
-static inline bool IS_ERR(const void *ptr)
-{
-	return IS_ERR_VALUE((unsigned long)ptr);
-}
-
-static inline bool IS_ERR_OR_NULL(const void *ptr)
-{
-	return (ptr == NULL) || IS_ERR_VALUE((unsigned long)ptr);
-}
-
 #define ERESTARTSYS ERESTART
 
 #endif /* NVGPU_POSIX_UTILS_H */

drivers/gpu/nvgpu/include/nvgpu/vidmem.h

@@ -54,6 +54,7 @@ struct nvgpu_vidmem_buf {
  *
  * @g     - The GPU.
  * @bytes - Size of the buffer in bytes.
+ * @vidmem_buf - Pointer to return vidmem buffer.
  *
  * Allocate a generic (OS agnostic) vidmem buffer. This does not allocate the OS
  * specific interfacing for userspace sharing. Instead is is expected that the
@@ -64,9 +65,10 @@ struct nvgpu_vidmem_buf {
  * extra struct over nvgpu_mem. If a vidmem buffer is needed by the kernel
  * driver only then a simple nvgpu_dma_alloc_vid() or the like is sufficient.
  *
- * Returns a pointer to a vidmem buffer on success, 0 otherwise.
+ * Returns 0 on success and error value on failure.
  */
-struct nvgpu_vidmem_buf *nvgpu_vidmem_user_alloc(struct gk20a *g, size_t bytes);
+int nvgpu_vidmem_user_alloc(struct gk20a *g, size_t bytes,
+				struct nvgpu_vidmem_buf **vidmem_buf);
 
 void nvgpu_vidmem_buf_free(struct gk20a *g, struct nvgpu_vidmem_buf *buf);
 

drivers/gpu/nvgpu/os/linux/dmabuf_vidmem.c

@@ -188,9 +188,8 @@ int nvgpu_vidmem_export_linux(struct gk20a *g, size_t bytes)
 		goto fail;
 	}
 
-	buf = nvgpu_vidmem_user_alloc(g, bytes);
-	if (IS_ERR(buf)) {
-		err = PTR_ERR(buf);
+	err = nvgpu_vidmem_user_alloc(g, bytes, &buf);
+	if (0 != err) {
 		goto fail;
 	}