[PATCH 2/2] drm: use mem_is_zero() instead of !memchr_inv(s, 0, n)

[Jani Nikula]

Use the mem_is_zero() helper where possible.

Conversion done using cocci:

| @@
| expression PTR;
| expression SIZE;
| @@
|
|   <...
| (
| - memchr_inv(PTR, 0, SIZE) == NULL
| + mem_is_zero(PTR, SIZE)
| |
| - !memchr_inv(PTR, 0, SIZE)
| + mem_is_zero(PTR, SIZE)
| |
| - memchr_inv(PTR, 0, SIZE)
| + !mem_is_zero(PTR, SIZE)
| )
|   ...>

Signed-off-by: Jani Nikula <jani.nikula at intel.com>

---

Cc: Kees Cook <keescook at chromium.org>
Cc: Andy Shevchenko <andy at kernel.org>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c    | 2 +-
 drivers/gpu/drm/display/drm_dp_mst_topology.c        | 2 +-
 drivers/gpu/drm/drm_edid.c                           | 2 +-
 drivers/gpu/drm/i915/display/intel_dp.c              | 2 +-
 drivers/gpu/drm/i915/display/intel_opregion.c        | 2 +-
 drivers/gpu/drm/i915/gem/selftests/i915_gem_dmabuf.c | 2 +-
 drivers/gpu/drm/imagination/pvr_device.h             | 2 +-
 drivers/gpu/drm/udl/udl_edid.c                       | 2 +-
 8 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 516eb3968e26..7d847021ddc9 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2432,7 +2432,7 @@ static void resume_mst_branch_status(struct drm_dp_mst_topology_mgr *mgr)
 		goto out_fail;
 	}
 
-	if (memchr_inv(guid, 0, 16) == NULL) {
+	if (mem_is_zero(guid, 16)) {
 		tmp64 = get_jiffies_64();
 		memcpy(&guid[0], &tmp64, sizeof(u64));
 		memcpy(&guid[8], &tmp64, sizeof(u64));
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 7f8e1cfbe19d..3d3097422235 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -2697,7 +2697,7 @@ static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
 {
 	u64 salt;
 
-	if (memchr_inv(guid, 0, 16))
+	if (!mem_is_zero(guid, 16))
 		return true;
 
 	salt = get_jiffies_64();
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index f68a41eeb1fa..9970c22f616b 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1817,7 +1817,7 @@ static int edid_block_tag(const void *_block)
 
 static bool edid_block_is_zero(const void *edid)
 {
-	return !memchr_inv(edid, 0, EDID_LENGTH);
+	return mem_is_zero(edid, EDID_LENGTH);
 }
 
 static bool drm_edid_eq(const struct drm_edid *drm_edid,
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index c0a3b6d50681..be3685e115ab 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5055,7 +5055,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
 			ack[3] |= DP_TUNNELING_IRQ;
 		}
 
-		if (!memchr_inv(ack, 0, sizeof(ack)))
+		if (mem_is_zero(ack, sizeof(ack)))
 			break;
 
 		if (!intel_dp_ack_sink_irq_esi(intel_dp, ack))
diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c
index 68bd5101ec89..293c4d920cf9 100644
--- a/drivers/gpu/drm/i915/display/intel_opregion.c
+++ b/drivers/gpu/drm/i915/display/intel_opregion.c
@@ -1117,7 +1117,7 @@ const struct drm_edid *intel_opregion_get_edid(struct intel_connector *intel_con
 
 	/* Validity corresponds to number of 128-byte blocks */
 	len = (opregion->asle_ext->phed & ASLE_PHED_EDID_VALID_MASK) * 128;
-	if (!len || !memchr_inv(edid, 0, len))
+	if (!len || mem_is_zero(edid, len))
 		return NULL;
 
 	drm_edid = drm_edid_alloc(edid, len);
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_dmabuf.c
index 3527b8f446fe..2fda549dd82d 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_dmabuf.c
@@ -506,7 +506,7 @@ static int igt_dmabuf_export_vmap(void *arg)
 		goto out;
 	}
 
-	if (memchr_inv(ptr, 0, dmabuf->size)) {
+	if (!mem_is_zero(ptr, dmabuf->size)) {
 		pr_err("Exported object not initialised to zero!\n");
 		err = -EINVAL;
 		goto out;
diff --git a/drivers/gpu/drm/imagination/pvr_device.h b/drivers/gpu/drm/imagination/pvr_device.h
index ecdd5767d8ef..b574e23d484b 100644
--- a/drivers/gpu/drm/imagination/pvr_device.h
+++ b/drivers/gpu/drm/imagination/pvr_device.h
@@ -668,7 +668,7 @@ pvr_ioctl_union_padding_check(void *instance, size_t union_offset,
 	void *padding_start = ((u8 *)instance) + union_offset + member_size;
 	size_t padding_size = union_size - member_size;
 
-	return !memchr_inv(padding_start, 0, padding_size);
+	return mem_is_zero(padding_start, padding_size);
 }
 
 /**
diff --git a/drivers/gpu/drm/udl/udl_edid.c b/drivers/gpu/drm/udl/udl_edid.c
index d67e6bf1f2ae..12f48ae17073 100644
--- a/drivers/gpu/drm/udl/udl_edid.c
+++ b/drivers/gpu/drm/udl/udl_edid.c
@@ -69,7 +69,7 @@ bool udl_probe_edid(struct udl_device *udl)
 	 * The adapter sends all-zeros if no monitor has been
 	 * connected. We consider anything else a connection.
 	 */
-	return !!memchr_inv(hdr, 0, sizeof(hdr));
+	return !mem_is_zero(hdr, sizeof(hdr));
 }
 
 const struct drm_edid *udl_edid_read(struct drm_connector *connector)
-- 
2.39.2