driver core: Replace dev->state_synced with dev_state_synced()

In C, bitfields are not necessarily safe to modify from multiple
threads without locking. Switch "state_synced" over to the "flags"
field so modifications are safe.

Cc: Saravana Kannan <saravanak@kernel.org>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patch.msgid.link/20260406162231.v5.6.Idb4818e1159fef104c7756bfd6e7ba8f374bebcd@changeid
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 43bbd1716f3702d396ec0f80a5ab40d924618efa..7517738dfcd238b82fa2997f6275e868afa637c4 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1123,7 +1123,7 @@ static void __device_links_queue_sync_state(struct device *dev,
 
        if (!dev_has_sync_state(dev))
                return;
-       if (dev->state_synced)
+       if (dev_state_synced(dev))
                return;
 
        list_for_each_entry(link, &dev->links.consumers, s_node) {
@@ -1138,7 +1138,7 @@ static void __device_links_queue_sync_state(struct device *dev,
         * than once. This can happen if new consumers get added to the device
         * and probed before the list is flushed.
         */
-       dev->state_synced = true;
+       dev_set_state_synced(dev);
 
        if (WARN_ON(!list_empty(&dev->links.defer_sync)))
                return;
@@ -1779,7 +1779,7 @@ static int fw_devlink_dev_sync_state(struct device *dev, void *data)
        struct device *sup = link->supplier;
 
        if (!device_link_test(link, DL_FLAG_MANAGED) ||
-           link->status == DL_STATE_ACTIVE || sup->state_synced ||
+           link->status == DL_STATE_ACTIVE || dev_state_synced(sup) ||
            !dev_has_sync_state(sup))
                return 0;
 
@@ -1793,7 +1793,7 @@ static int fw_devlink_dev_sync_state(struct device *dev, void *data)
                return 0;
 
        dev_warn(sup, "Timed out. Forcing sync_state()\n");
-       sup->state_synced = true;
+       dev_set_state_synced(sup);
        get_device(sup);
        list_add_tail(&sup->links.defer_sync, data);
 

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index bce1e63b42304d8e9b812c857a23afcc7701db4c..5799a60fd058582b020237e41e359d0fa99d59ec 100644 (file)
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -569,12 +569,10 @@ static ssize_t state_synced_store(struct device *dev,
                return -EINVAL;
 
        device_lock(dev);
-       if (!dev->state_synced) {
-               dev->state_synced = true;
+       if (!dev_test_and_set_state_synced(dev))
                dev_sync_state(dev);
-       } else {
+       else
                ret = -EINVAL;
-       }
        device_unlock(dev);
 
        return ret ? ret : count;
@@ -586,7 +584,7 @@ static ssize_t state_synced_show(struct device *dev,
        bool val;
 
        device_lock(dev);
-       val = dev->state_synced;
+       val = dev_state_synced(dev);
        device_unlock(dev);
 
        return sysfs_emit(buf, "%u\n", val);

diff --git a/include/linux/device.h b/include/linux/device.h
index 099533cbdd2ff0cdb439a7a9a08376bbe09d2e2e..fc4334ff33519934c77a2aa51d81d331fe5f857e 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -524,6 +524,9 @@ struct device_physical_location {
  *             optional (if the coherent mask is large enough) also for dma
  *             allocations. This flag is managed by the dma ops instance from
  *             ->dma_supported.
+ * @DEV_FLAG_STATE_SYNCED: The hardware state of this device has been synced to
+ *             match the software state of this device by calling the
+ *             driver/bus sync_state() callback.
  * @DEV_FLAG_COUNT: Number of defined struct_device_flags.
  */
 enum struct_device_flags {
@@ -532,6 +535,7 @@ enum struct_device_flags {
        DEV_FLAG_DMA_IOMMU = 2,
        DEV_FLAG_DMA_SKIP_SYNC = 3,
        DEV_FLAG_DMA_OPS_BYPASS = 4,
+       DEV_FLAG_STATE_SYNCED = 5,
 
        DEV_FLAG_COUNT
 };
@@ -615,9 +619,6 @@ enum struct_device_flags {
  * @offline:   Set after successful invocation of bus type's .offline().
  * @of_node_reused: Set if the device-tree node is shared with an ancestor
  *              device.
- * @state_synced: The hardware state of this device has been synced to match
- *               the software state of this device by calling the driver/bus
- *               sync_state() callback.
  * @dma_coherent: this particular device is dma coherent, even if the
  *             architecture supports non-coherent devices.
  * @flags:     DEV_FLAG_XXX flags. Use atomic bitfield operations to modify.
@@ -727,7 +728,6 @@ struct device {
        bool                    offline_disabled:1;
        bool                    offline:1;
        bool                    of_node_reused:1;
-       bool                    state_synced:1;
 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
     defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
@@ -764,6 +764,7 @@ __create_dev_flag_accessors(can_match, DEV_FLAG_CAN_MATCH);
 __create_dev_flag_accessors(dma_iommu, DEV_FLAG_DMA_IOMMU);
 __create_dev_flag_accessors(dma_skip_sync, DEV_FLAG_DMA_SKIP_SYNC);
 __create_dev_flag_accessors(dma_ops_bypass, DEV_FLAG_DMA_OPS_BYPASS);
+__create_dev_flag_accessors(state_synced, DEV_FLAG_STATE_SYNCED);
 
 #undef __create_dev_flag_accessors