Merge branch 'devlink-flash-update-overwrite-mask'

Jacob Keller says:

====================
devlink flash update overwrite mask

This series introduces support for a new attribute to the flash update
command: DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK.

This attribute is a bitfield which allows userspace to specify what set of
subfields to overwrite when performing a flash update for a device.

The intention is to support the ability to control the behavior of
overwriting the configuration and identifying fields in the Intel ice device
flash update process. This is necessary  as the firmware layout for the ice
device includes some settings and configuration within the same flash
section as the main firmware binary.

This series, and the accompanying iproute2 series, introduce support for the
attribute. Once applied, the overwrite support can be be invoked via
devlink:

  # overwrite settings
  devlink dev flash pci/0000:af:00.0 file firmware.bin overwrite settings

  # overwrite identifiers and settings
  devlink dev flash pci/0000:af:00.0 file firmware.bin overwrite settings overwrite identifiers

To aid in the safe addition of new parameters, first some refactoring is
done to the .flash_update function: its parameters are converted from a
series of function arguments into a structure. This makes it easier to add
the new parameter without changing the signature of the .flash_update
handler in the future. Additionally, a "supported_flash_update_params" field
is added to devlink_ops. This field is similar to the ethtool
"supported_coalesc_params" field. The devlink core will now check that the
DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT bit is set before forwarding the
component attribute. Similarly, the new overwrite attribute will also
require a supported bit.

Doing these refactors will aid in adding any other attributes in the future,
and creates a good pattern for other interfaces to use in the future. By
requiring drivers to opt-in, we reduce the risk of accidentally breaking
drivers when ever we add an additional parameter. We also reduce boiler
plate code in drivers which do not support the parameters.

Changes since v9:
* rebased to current net-next, no other changes

Changes since v7
* resend, hopefully avoiding the SMTP server issues I experienced on Friday

Changes since v6
* Rebased to current net-next to resolve conflicts
* Added changes to the ionic driver that recently merged flash update support
* Fixed the changes for mlxsw to apply to core instead of spectrum.c after
  the recent refactor.
* Picked up the review tags from Jakub

Changes since v5
* Fix *all* of the BIT usage to use _BITUL() (thanks Jakub!)

Changes since v4
* Renamed nla_overwrite to nla_overwrite_mask at Jiri's suggestion
* Added "by this device" to the netlink error messages for unsupported
  attributes
* Removed use of BIT() in the uapi header
* Fixed the commit message for the netdevsim patch
* Picked up Jakub's reviewed
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/devlink/devlink-flash.rst

@@ -16,6 +16,34 @@ Note that the file name is a path relative to the firmware loading path
 (usually ``/lib/firmware/``). Drivers may send status updates to inform
 user space about the progress of the update operation.
 
+Overwrite Mask
+==============
+
+The ``devlink-flash`` command allows optionally specifying a mask indicating
+how the device should handle subsections of flash components when updating.
+This mask indicates the set of sections which are allowed to be overwritten.
+
+.. list-table:: List of overwrite mask bits
+   :widths: 5 95
+
+   * - Name
+     - Description
+   * - ``DEVLINK_FLASH_OVERWRITE_SETTINGS``
+     - Indicates that the device should overwrite settings in the components
+       being updated with the settings found in the provided image.
+   * - ``DEVLINK_FLASH_OVERWRITE_IDENTIFIERS``
+     - Indicates that the device should overwrite identifiers in the
+       components being updated with the identifiers found in the provided
+       image. This includes MAC addresses, serial IDs, and similar device
+       identifiers.
+
+Multiple overwrite bits may be combined and requested together. If no bits
+are provided, it is expected that the device only update firmware binaries
+in the components being updated. Settings and identifiers are expected to be
+preserved across the update. A device may not support every combination and
+the driver for such a device must reject any combination which cannot be
+faithfully implemented.
+
 Firmware Loading
 ================
 

Documentation/networking/devlink/ice.rst

@@ -81,6 +81,37 @@ The ``ice`` driver reports the following versions
       - 0xee16ced7
       - The first 4 bytes of the hash of the netlist module contents.
 
+Flash Update
+============
+
+The ``ice`` driver implements support for flash update using the
+``devlink-flash`` interface. It supports updating the device flash using a
+combined flash image that contains the ``fw.mgmt``, ``fw.undi``, and
+``fw.netlist`` components.
+
+.. list-table:: List of supported overwrite modes
+   :widths: 5 95
+
+   * - Bits
+     - Behavior
+   * - ``DEVLINK_FLASH_OVERWRITE_SETTINGS``
+     - Do not preserve settings stored in the flash components being
+       updated. This includes overwriting the port configuration that
+       determines the number of physical functions the device will
+       initialize with.
+   * - ``DEVLINK_FLASH_OVERWRITE_SETTINGS`` and ``DEVLINK_FLASH_OVERWRITE_IDENTIFIERS``
+     - Do not preserve either settings or identifiers. Overwrite everything
+       in the flash with the contents from the provided image, without
+       performing any preservation. This includes overwriting device
+       identifying fields such as the MAC address, VPD area, and device
+       serial number. It is expected that this combination be used with an
+       image customized for the specific device.
+
+The ice hardware does not support overwriting only identifiers while
+preserving settings, and thus ``DEVLINK_FLASH_OVERWRITE_IDENTIFIERS`` on its
+own will be rejected. If no overwrite mask is provided, the firmware will be
+instructed to preserve all settings and identifying fields when updating.
+
 Regions
 =======
 

drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c

@@ -17,15 +17,13 @@
 #include "bnxt_ethtool.h"
 
 static int
-bnxt_dl_flash_update(struct devlink *dl, const char *filename,
-		     const char *region, struct netlink_ext_ack *extack)
+bnxt_dl_flash_update(struct devlink *dl,
+		     struct devlink_flash_update_params *params,
+		     struct netlink_ext_ack *extack)
 {
 	struct bnxt *bp = bnxt_get_bp_from_dl(dl);
 	int rc;
 
-	if (region)
-		return -EOPNOTSUPP;
-
 	if (!BNXT_PF(bp)) {
 		NL_SET_ERR_MSG_MOD(extack,
 				   "flash update not supported from a VF");
@@ -33,15 +31,12 @@ bnxt_dl_flash_update(struct devlink *dl, const char *filename,
 	}
 
 	devlink_flash_update_begin_notify(dl);
-	devlink_flash_update_status_notify(dl, "Preparing to flash", region, 0,
-					   0);
-	rc = bnxt_flash_package_from_file(bp->dev, filename, 0);
+	devlink_flash_update_status_notify(dl, "Preparing to flash", NULL, 0, 0);
+	rc = bnxt_flash_package_from_file(bp->dev, params->file_name, 0);
 	if (!rc)
-		devlink_flash_update_status_notify(dl, "Flashing done", region,
-						   0, 0);
+		devlink_flash_update_status_notify(dl, "Flashing done", NULL, 0, 0);
 	else
-		devlink_flash_update_status_notify(dl, "Flashing failed",
-						   region, 0, 0);
+		devlink_flash_update_status_notify(dl, "Flashing failed", NULL, 0, 0);
 	devlink_flash_update_end_notify(dl);
 	return rc;
 }

drivers/net/ethernet/huawei/hinic/hinic_devlink.c

@@ -281,18 +281,14 @@ static int hinic_firmware_update(struct hinic_devlink_priv *priv,
 }
 
 static int hinic_devlink_flash_update(struct devlink *devlink,
-				      const char *file_name,
-				      const char *component,
+				      struct devlink_flash_update_params *params,
 				      struct netlink_ext_ack *extack)
 {
 	struct hinic_devlink_priv *priv = devlink_priv(devlink);
 	const struct firmware *fw;
 	int err;
 
-	if (component)
-		return -EOPNOTSUPP;
-
-	err = request_firmware_direct(&fw, file_name,
+	err = request_firmware_direct(&fw, params->file_name,
 				      &priv->hwdev->hwif->pdev->dev);
 	if (err)
 		return err;

drivers/net/ethernet/intel/ice/ice_devlink.c

@@ -233,8 +233,7 @@ static int ice_devlink_info_get(struct devlink *devlink,
 /**
  * ice_devlink_flash_update - Update firmware stored in flash on the device
  * @devlink: pointer to devlink associated with device to update
- * @path: the path of the firmware file to use via request_firmware
- * @component: name of the component to update, or NULL
+ * @params: flash update parameters
  * @extack: netlink extended ACK structure
  *
  * Perform a device flash update. The bulk of the update logic is contained
@@ -243,38 +242,50 @@ static int ice_devlink_info_get(struct devlink *devlink,
  * Returns: zero on success, or an error code on failure.
  */
 static int
-ice_devlink_flash_update(struct devlink *devlink, const char *path,
-			 const char *component, struct netlink_ext_ack *extack)
+ice_devlink_flash_update(struct devlink *devlink,
+			 struct devlink_flash_update_params *params,
+			 struct netlink_ext_ack *extack)
 {
 	struct ice_pf *pf = devlink_priv(devlink);
 	struct device *dev = &pf->pdev->dev;
 	struct ice_hw *hw = &pf->hw;
 	const struct firmware *fw;
+	u8 preservation;
 	int err;
 
-	/* individual component update is not yet supported */
-	if (component)
+	if (!params->overwrite_mask) {
+		/* preserve all settings and identifiers */
+		preservation = ICE_AQC_NVM_PRESERVE_ALL;
+	} else if (params->overwrite_mask == DEVLINK_FLASH_OVERWRITE_SETTINGS) {
+		/* overwrite settings, but preserve the vital device identifiers */
+		preservation = ICE_AQC_NVM_PRESERVE_SELECTED;
+	} else if (params->overwrite_mask == (DEVLINK_FLASH_OVERWRITE_SETTINGS |
+					      DEVLINK_FLASH_OVERWRITE_IDENTIFIERS)) {
+		/* overwrite both settings and identifiers, preserve nothing */
+		preservation = ICE_AQC_NVM_NO_PRESERVATION;
+	} else {
+		NL_SET_ERR_MSG_MOD(extack, "Requested overwrite mask is not supported");
 		return -EOPNOTSUPP;
+	}
 
 	if (!hw->dev_caps.common_cap.nvm_unified_update) {
 		NL_SET_ERR_MSG_MOD(extack, "Current firmware does not support unified update");
 		return -EOPNOTSUPP;
 	}
 
-	err = ice_check_for_pending_update(pf, component, extack);
+	err = ice_check_for_pending_update(pf, NULL, extack);
 	if (err)
 		return err;
 
-	err = request_firmware(&fw, path, dev);
+	err = request_firmware(&fw, params->file_name, dev);
 	if (err) {
 		NL_SET_ERR_MSG_MOD(extack, "Unable to read file from disk");
 		return err;
 	}
 
 	devlink_flash_update_begin_notify(devlink);
-	devlink_flash_update_status_notify(devlink, "Preparing to flash",
-					   component, 0, 0);
-	err = ice_flash_pldm_image(pf, fw, extack);
+	devlink_flash_update_status_notify(devlink, "Preparing to flash", NULL, 0, 0);
+	err = ice_flash_pldm_image(pf, fw, preservation, extack);
 	devlink_flash_update_end_notify(devlink);
 
 	release_firmware(fw);
@@ -283,6 +294,7 @@ ice_devlink_flash_update(struct devlink *devlink, const char *path,
 }
 
 static const struct devlink_ops ice_devlink_ops = {
+	.supported_flash_update_params = DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK,
 	.info_get = ice_devlink_info_get,
 	.flash_update = ice_devlink_flash_update,
 };

drivers/net/ethernet/intel/ice/ice_fw_update.c

@@ -625,6 +625,7 @@ static const struct pldmfw_ops ice_fwu_ops = {
  * ice_flash_pldm_image - Write a PLDM-formatted firmware image to the device
  * @pf: private device driver structure
  * @fw: firmware object pointing to the relevant firmware file
+ * @preservation: preservation level to request from firmware
  * @extack: netlink extended ACK structure
  *
  * Parse the data for a given firmware file, verifying that it is a valid PLDM
@@ -638,7 +639,7 @@ static const struct pldmfw_ops ice_fwu_ops = {
  * Returns: zero on success or a negative error code on failure.
  */
 int ice_flash_pldm_image(struct ice_pf *pf, const struct firmware *fw,
-			 struct netlink_ext_ack *extack)
+			 u8 preservation, struct netlink_ext_ack *extack)
 {
 	struct device *dev = ice_pf_to_dev(pf);
 	struct ice_hw *hw = &pf->hw;
@@ -646,13 +647,24 @@ int ice_flash_pldm_image(struct ice_pf *pf, const struct firmware *fw,
 	enum ice_status status;
 	int err;
 
+	switch (preservation) {
+	case ICE_AQC_NVM_PRESERVE_ALL:
+	case ICE_AQC_NVM_PRESERVE_SELECTED:
+	case ICE_AQC_NVM_NO_PRESERVATION:
+	case ICE_AQC_NVM_FACTORY_DEFAULT:
+		break;
+	default:
+		WARN(1, "Unexpected preservation level request %u", preservation);
+		return -EINVAL;
+	}
+
 	memset(&priv, 0, sizeof(priv));
 
 	priv.context.ops = &ice_fwu_ops;
 	priv.context.dev = dev;
 	priv.extack = extack;
 	priv.pf = pf;
-	priv.activate_flags = ICE_AQC_NVM_PRESERVE_ALL;
+	priv.activate_flags = preservation;
 
 	status = ice_acquire_nvm(hw, ICE_RES_WRITE);
 	if (status) {

drivers/net/ethernet/intel/ice/ice_fw_update.h

@@ -5,7 +5,7 @@
 #define _ICE_FW_UPDATE_H_
 
 int ice_flash_pldm_image(struct ice_pf *pf, const struct firmware *fw,
-			 struct netlink_ext_ack *extack);
+			 u8 preservation, struct netlink_ext_ack *extack);
 int ice_check_for_pending_update(struct ice_pf *pf, const char *component,
 				 struct netlink_ext_ack *extack);
 

drivers/net/ethernet/mellanox/mlx5/core/devlink.c

@@ -8,18 +8,14 @@
 #include "eswitch.h"
 
 static int mlx5_devlink_flash_update(struct devlink *devlink,
-				     const char *file_name,
-				     const char *component,
+				     struct devlink_flash_update_params *params,
 				     struct netlink_ext_ack *extack)
 {
 	struct mlx5_core_dev *dev = devlink_priv(devlink);
 	const struct firmware *fw;
 	int err;
 
-	if (component)
-		return -EOPNOTSUPP;
-
-	err = request_firmware_direct(&fw, file_name, &dev->pdev->dev);
+	err = request_firmware_direct(&fw, params->file_name, &dev->pdev->dev);
 	if (err)
 		return err;
 

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -1102,16 +1102,13 @@ static int mlxsw_core_fw_rev_validate(struct mlxsw_core *mlxsw_core,
 }
 
 static int mlxsw_core_fw_flash_update(struct mlxsw_core *mlxsw_core,
-				      const char *file_name, const char *component,
+				      struct devlink_flash_update_params *params,
 				      struct netlink_ext_ack *extack)
 {
 	const struct firmware *firmware;
 	int err;
 
-	if (component)
-		return -EOPNOTSUPP;
-
-	err = request_firmware_direct(&firmware, file_name, mlxsw_core->bus_info->dev);
+	err = request_firmware_direct(&firmware, params->file_name, mlxsw_core->bus_info->dev);
 	if (err)
 		return err;
 	err = mlxsw_core_fw_flash(mlxsw_core, firmware, extack);
@@ -1434,13 +1431,12 @@ mlxsw_devlink_core_bus_device_reload_up(struct devlink *devlink,
 }
 
 static int mlxsw_devlink_flash_update(struct devlink *devlink,
-				      const char *file_name,
-				      const char *component,
+				      struct devlink_flash_update_params *params,
 				      struct netlink_ext_ack *extack)
 {
 	struct mlxsw_core *mlxsw_core = devlink_priv(devlink);
 
-	return mlxsw_core_fw_flash_update(mlxsw_core, file_name, component, extack);
+	return mlxsw_core_fw_flash_update(mlxsw_core, params, extack);
 }
 
 static int mlxsw_devlink_trap_init(struct devlink *devlink,

drivers/net/ethernet/netronome/nfp/nfp_devlink.c

@@ -329,12 +329,11 @@ nfp_devlink_info_get(struct devlink *devlink, struct devlink_info_req *req,
 }
 
 static int
-nfp_devlink_flash_update(struct devlink *devlink, const char *path,
-			 const char *component, struct netlink_ext_ack *extack)
+nfp_devlink_flash_update(struct devlink *devlink,
+			 struct devlink_flash_update_params *params,
+			 struct netlink_ext_ack *extack)
 {
-	if (component)
-		return -EOPNOTSUPP;
-	return nfp_flash_update_common(devlink_priv(devlink), path, extack);
+	return nfp_flash_update_common(devlink_priv(devlink), params->file_name, extack);
 }
 
 const struct devlink_ops nfp_devlink_ops = {

drivers/net/ethernet/pensando/ionic/ionic_devlink.c

@@ -10,16 +10,12 @@
 #include "ionic_devlink.h"
 
 static int ionic_dl_flash_update(struct devlink *dl,
-				 const char *fwname,
-				 const char *component,
+				 struct devlink_flash_update_params *params,
 				 struct netlink_ext_ack *extack)
 {
 	struct ionic *ionic = devlink_priv(dl);
 
-	if (component)
-		return -EOPNOTSUPP;
-
-	return ionic_firmware_update(ionic->lif, fwname, extack);
+	return ionic_firmware_update(ionic->lif, params->file_name, extack);
 }
 
 static int ionic_dl_info_get(struct devlink *dl, struct devlink_info_req *req,

drivers/net/netdevsim/dev.c

@@ -203,6 +203,8 @@ static int nsim_dev_debugfs_init(struct nsim_dev *nsim_dev)
 		return PTR_ERR(nsim_dev->ports_ddir);
 	debugfs_create_bool("fw_update_status", 0600, nsim_dev->ddir,
 			    &nsim_dev->fw_update_status);
+	debugfs_create_u32("fw_update_overwrite_mask", 0600, nsim_dev->ddir,
+			    &nsim_dev->fw_update_overwrite_mask);
 	debugfs_create_u32("max_macs", 0600, nsim_dev->ddir,
 			   &nsim_dev->max_macs);
 	debugfs_create_bool("test1", 0600, nsim_dev->ddir,
@@ -742,24 +744,27 @@ static int nsim_dev_info_get(struct devlink *devlink,
 #define NSIM_DEV_FLASH_CHUNK_SIZE 1000
 #define NSIM_DEV_FLASH_CHUNK_TIME_MS 10
 
-static int nsim_dev_flash_update(struct devlink *devlink, const char *file_name,
-				 const char *component,
+static int nsim_dev_flash_update(struct devlink *devlink,
+				 struct devlink_flash_update_params *params,
 				 struct netlink_ext_ack *extack)
 {
 	struct nsim_dev *nsim_dev = devlink_priv(devlink);
 	int i;
 
+	if ((params->overwrite_mask & ~nsim_dev->fw_update_overwrite_mask) != 0)
+		return -EOPNOTSUPP;
+
 	if (nsim_dev->fw_update_status) {
 		devlink_flash_update_begin_notify(devlink);
 		devlink_flash_update_status_notify(devlink,
 						   "Preparing to flash",
-						   component, 0, 0);
+						   params->component, 0, 0);
 	}
 
 	for (i = 0; i < NSIM_DEV_FLASH_SIZE / NSIM_DEV_FLASH_CHUNK_SIZE; i++) {
 		if (nsim_dev->fw_update_status)
 			devlink_flash_update_status_notify(devlink, "Flashing",
-							   component,
+							   params->component,
 							   i * NSIM_DEV_FLASH_CHUNK_SIZE,
 							   NSIM_DEV_FLASH_SIZE);
 		msleep(NSIM_DEV_FLASH_CHUNK_TIME_MS);
@@ -767,13 +772,13 @@ static int nsim_dev_flash_update(struct devlink *devlink, const char *file_name,
 
 	if (nsim_dev->fw_update_status) {
 		devlink_flash_update_status_notify(devlink, "Flashing",
-						   component,
+						   params->component,
 						   NSIM_DEV_FLASH_SIZE,
 						   NSIM_DEV_FLASH_SIZE);
 		devlink_flash_update_timeout_notify(devlink, "Flash select",
-						    component, 81);
+						    params->component, 81);
 		devlink_flash_update_status_notify(devlink, "Flashing done",
-						   component, 0, 0);
+						   params->component, 0, 0);
 		devlink_flash_update_end_notify(devlink);
 	}
 
@@ -879,6 +884,8 @@ nsim_dev_devlink_trap_policer_counter_get(struct devlink *devlink,
 }
 
 static const struct devlink_ops nsim_dev_devlink_ops = {
+	.supported_flash_update_params = DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT |
+					 DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK,
 	.reload_down = nsim_dev_reload_down,
 	.reload_up = nsim_dev_reload_up,
 	.info_get = nsim_dev_info_get,
@@ -993,6 +1000,7 @@ static int nsim_dev_reload_create(struct nsim_dev *nsim_dev,
 	INIT_LIST_HEAD(&nsim_dev->port_list);
 	mutex_init(&nsim_dev->port_list_lock);
 	nsim_dev->fw_update_status = true;
+	nsim_dev->fw_update_overwrite_mask = 0;
 
 	nsim_dev->fib_data = nsim_fib_create(devlink, extack);
 	if (IS_ERR(nsim_dev->fib_data))
@@ -1051,6 +1059,7 @@ int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev)
 	INIT_LIST_HEAD(&nsim_dev->port_list);
 	mutex_init(&nsim_dev->port_list_lock);
 	nsim_dev->fw_update_status = true;
+	nsim_dev->fw_update_overwrite_mask = 0;
 	nsim_dev->max_macs = NSIM_DEV_MAX_MACS_DEFAULT;
 	nsim_dev->test1 = NSIM_DEV_TEST1_DEFAULT;
 	spin_lock_init(&nsim_dev->fa_cookie_lock);

drivers/net/netdevsim/netdevsim.h

@@ -196,6 +196,7 @@ struct nsim_dev {
 	struct list_head port_list;
 	struct mutex port_list_lock; /* protects port list */
 	bool fw_update_status;
+	u32 fw_update_overwrite_mask;
 	u32 max_macs;
 	bool test1;
 	bool dont_allow_reload;

include/net/devlink.h

@@ -550,6 +550,24 @@ enum devlink_param_generic_id {
 /* Firmware bundle identifier */
 #define DEVLINK_INFO_VERSION_GENERIC_FW_BUNDLE_ID	"fw.bundle_id"
 
+/**
+ * struct devlink_flash_update_params - Flash Update parameters
+ * @file_name: the name of the flash firmware file to update from
+ * @component: the flash component to update
+ *
+ * With the exception of file_name, drivers must opt-in to parameters by
+ * setting the appropriate bit in the supported_flash_update_params field in
+ * their devlink_ops structure.
+ */
+struct devlink_flash_update_params {
+	const char *file_name;
+	const char *component;
+	u32 overwrite_mask;
+};
+
+#define DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT		BIT(0)
+#define DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK	BIT(1)
+
 struct devlink_region;
 struct devlink_info_req;
 
@@ -1037,6 +1055,12 @@ enum devlink_trap_group_generic_id {
 	}
 
 struct devlink_ops {
+	/**
+	 * @supported_flash_update_params:
+	 * mask of parameters supported by the driver's .flash_update
+	 * implemementation.
+	 */
+	u32 supported_flash_update_params;
 	int (*reload_down)(struct devlink *devlink, bool netns_change,
 			   struct netlink_ext_ack *extack);
 	int (*reload_up)(struct devlink *devlink,
@@ -1097,8 +1121,15 @@ struct devlink_ops {
 				      struct netlink_ext_ack *extack);
 	int (*info_get)(struct devlink *devlink, struct devlink_info_req *req,
 			struct netlink_ext_ack *extack);
-	int (*flash_update)(struct devlink *devlink, const char *file_name,
-			    const char *component,
+	/**
+	 * @flash_update: Device flash update function
+	 *
+	 * Used to perform a flash update for the device. The set of
+	 * parameters supported by the driver should be set in
+	 * supported_flash_update_params.
+	 */
+	int (*flash_update)(struct devlink *devlink,
+			    struct devlink_flash_update_params *params,
 			    struct netlink_ext_ack *extack);
 	/**
 	 * @trap_init: Trap initialization function.

include/uapi/linux/devlink.h

@@ -230,6 +230,28 @@ enum {
 	DEVLINK_ATTR_STATS_MAX = __DEVLINK_ATTR_STATS_MAX - 1
 };
 
+/* Specify what sections of a flash component can be overwritten when
+ * performing an update. Overwriting of firmware binary sections is always
+ * implicitly assumed to be allowed.
+ *
+ * Each section must be documented in
+ * Documentation/networking/devlink/devlink-flash.rst
+ *
+ */
+enum {
+	DEVLINK_FLASH_OVERWRITE_SETTINGS_BIT,
+	DEVLINK_FLASH_OVERWRITE_IDENTIFIERS_BIT,
+
+	__DEVLINK_FLASH_OVERWRITE_MAX_BIT,
+	DEVLINK_FLASH_OVERWRITE_MAX_BIT = __DEVLINK_FLASH_OVERWRITE_MAX_BIT - 1
+};
+
+#define DEVLINK_FLASH_OVERWRITE_SETTINGS _BITUL(DEVLINK_FLASH_OVERWRITE_SETTINGS_BIT)
+#define DEVLINK_FLASH_OVERWRITE_IDENTIFIERS _BITUL(DEVLINK_FLASH_OVERWRITE_IDENTIFIERS_BIT)
+
+#define DEVLINK_SUPPORTED_FLASH_OVERWRITE_SECTIONS \
+	(_BITUL(__DEVLINK_FLASH_OVERWRITE_MAX_BIT) - 1)
+
 /**
  * enum devlink_trap_action - Packet trap action.
  * @DEVLINK_TRAP_ACTION_DROP: Packet is dropped by the device and a copy is not
@@ -464,6 +486,7 @@ enum devlink_attr {
 	DEVLINK_ATTR_PORT_CONTROLLER_NUMBER,	/* u32 */
 
 	DEVLINK_ATTR_FLASH_UPDATE_STATUS_TIMEOUT,	/* u64 */
+	DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK,	/* bitfield32 */
 
 	/* add new attributes above here, update the policy in devlink.c */
 

net/core/devlink.c

@@ -3147,22 +3147,45 @@ EXPORT_SYMBOL_GPL(devlink_flash_update_timeout_notify);
 static int devlink_nl_cmd_flash_update(struct sk_buff *skb,
 				       struct genl_info *info)
 {
+	struct nlattr *nla_component, *nla_overwrite_mask;
+	struct devlink_flash_update_params params = {};
 	struct devlink *devlink = info->user_ptr[0];
-	const char *file_name, *component;
-	struct nlattr *nla_component;
+	u32 supported_params;
 
 	if (!devlink->ops->flash_update)
 		return -EOPNOTSUPP;
 
 	if (!info->attrs[DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME])
 		return -EINVAL;
-	file_name = nla_data(info->attrs[DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME]);
+
+	supported_params = devlink->ops->supported_flash_update_params;
+
+	params.file_name = nla_data(info->attrs[DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME]);
 
 	nla_component = info->attrs[DEVLINK_ATTR_FLASH_UPDATE_COMPONENT];
-	component = nla_component ? nla_data(nla_component) : NULL;
+	if (nla_component) {
+		if (!(supported_params & DEVLINK_SUPPORT_FLASH_UPDATE_COMPONENT)) {
+			NL_SET_ERR_MSG_ATTR(info->extack, nla_component,
+					    "component update is not supported by this device");
+			return -EOPNOTSUPP;
+		}
+		params.component = nla_data(nla_component);
+	}
+
+	nla_overwrite_mask = info->attrs[DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK];
+	if (nla_overwrite_mask) {
+		struct nla_bitfield32 sections;
 
-	return devlink->ops->flash_update(devlink, file_name, component,
-					  info->extack);
+		if (!(supported_params & DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK)) {
+			NL_SET_ERR_MSG_ATTR(info->extack, nla_overwrite_mask,
+					    "overwrite settings are not supported by this device");
+			return -EOPNOTSUPP;
+		}
+		sections = nla_get_bitfield32(nla_overwrite_mask);
+		params.overwrite_mask = sections.value & sections.selector;
+	}
+
+	return devlink->ops->flash_update(devlink, &params, info->extack);
 }
 
 static const struct devlink_param devlink_param_generic[] = {
@@ -7083,6 +7106,8 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_HEALTH_REPORTER_AUTO_RECOVER] = { .type = NLA_U8 },
 	[DEVLINK_ATTR_FLASH_UPDATE_FILE_NAME] = { .type = NLA_NUL_STRING },
 	[DEVLINK_ATTR_FLASH_UPDATE_COMPONENT] = { .type = NLA_NUL_STRING },
+	[DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK] =
+		NLA_POLICY_BITFIELD32(DEVLINK_SUPPORTED_FLASH_OVERWRITE_SECTIONS),
 	[DEVLINK_ATTR_TRAP_NAME] = { .type = NLA_NUL_STRING },
 	[DEVLINK_ATTR_TRAP_ACTION] = { .type = NLA_U8 },
 	[DEVLINK_ATTR_TRAP_GROUP_NAME] = { .type = NLA_NUL_STRING },
@@ -9640,6 +9665,7 @@ void devlink_compat_running_version(struct net_device *dev,
 
 int devlink_compat_flash_update(struct net_device *dev, const char *file_name)
 {
+	struct devlink_flash_update_params params = {};
 	struct devlink *devlink;
 	int ret;
 
@@ -9652,8 +9678,10 @@ int devlink_compat_flash_update(struct net_device *dev, const char *file_name)
 		goto out;
 	}
 
+	params.file_name = file_name;
+
 	mutex_lock(&devlink->lock);
-	ret = devlink->ops->flash_update(devlink, file_name, NULL, NULL);
+	ret = devlink->ops->flash_update(devlink, &params, NULL);
 	mutex_unlock(&devlink->lock);
 
 out:

tools/testing/selftests/drivers/net/netdevsim/devlink.sh

@@ -23,6 +23,27 @@ fw_flash_test()
 	devlink dev flash $DL_HANDLE file dummy
 	check_err $? "Failed to flash with status updates on"
 
+	devlink dev flash $DL_HANDLE file dummy component fw.mgmt
+	check_err $? "Failed to flash with component attribute"
+
+	devlink dev flash $DL_HANDLE file dummy overwrite settings
+	check_fail $? "Flash with overwrite settings should be rejected"
+
+	echo "1"> $DEBUGFS_DIR/fw_update_overwrite_mask
+	check_err $? "Failed to change allowed overwrite mask"
+
+	devlink dev flash $DL_HANDLE file dummy overwrite settings
+	check_err $? "Failed to flash with settings overwrite enabled"
+
+	devlink dev flash $DL_HANDLE file dummy overwrite identifiers
+	check_fail $? "Flash with overwrite settings should be identifiers"
+
+	echo "3"> $DEBUGFS_DIR/fw_update_overwrite_mask
+	check_err $? "Failed to change allowed overwrite mask"
+
+	devlink dev flash $DL_HANDLE file dummy overwrite identifiers overwrite settings
+	check_err $? "Failed to flash with settings and identifiers overwrite enabled"
+
 	echo "n"> $DEBUGFS_DIR/fw_update_status
 	check_err $? "Failed to disable status updates"