[PATCH v7 08/12] vdpa: Use helper for safer setting of driver_override

Krzysztof Kozlowski
2022-04-19T11:35:33Z

Use a helper to set driver_override to the reduce amount of duplicated
code.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/vdpa/vdpa.c | 29 ++++-------------------------
include/linux/vdpa.h | 4 +++-
2 files changed, 7 insertions(+), 26 deletions(-)

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 2b75c00b1005..33d1ad60cba7 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -77,32 +77,11 @@ static ssize_t driver_override_store(struct device *dev,
const char *buf, size_t count)
{
struct vdpa_device *vdev = dev_to_vdpa(dev);
- const char *driver_override, *old;
- char *cp;
+ int ret;

- /* We need to keep extra room for a newline */
- if (count >= (PAGE_SIZE - 1))
- return -EINVAL;
-
- driver_override = kstrndup(buf, count, GFP_KERNEL);
- if (!driver_override)
- return -ENOMEM;
-
- cp = strchr(driver_override, '\n');
- if (cp)
- *cp = '\0';
-
- device_lock(dev);
- old = vdev->driver_override;
- if (strlen(driver_override)) {
- vdev->driver_override = driver_override;
- } else {
- kfree(driver_override);
- vdev->driver_override = NULL;
- }
- device_unlock(dev);
-
- kfree(old);
+ ret = driver_set_override(dev, &vdev->driver_override, buf, count);
+ if (ret)
+ return ret;

return count;
}
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 8943a209202e..c0a5083632ab 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -64,7 +64,9 @@ struct vdpa_mgmt_dev;
* struct vdpa_device - representation of a vDPA device
* @dev: underlying device
* @dma_dev: the actual device that is performing DMA
- * @driver_override: driver name to force a match
+ * @driver_override: driver name to force a match; do not set directly,
+ * because core frees it; use driver_set_override() to
+ * set or clear it.
* @config: the configuration ops for this device.
* @cf_mutex: Protects get and set access to configuration layout.
* @index: device index
--
2.32.0