[PATCH v2 16/20] efi_loader: disk: a helper function to delete efi_disk objects

[AKASHI Takahiro]

This function is expected to be called, in particular from dm's pre_remove
hook, when associated block devices no longer exist.

Add efi_disk_remove() function.
This function removes an efi_disk object for a raw disk device (UCLASS_BLK)
and related objects for its partitions (UCLASS_PARTITION).

So this function is expected to be called through driver model's "remove"
interface every time a raw disk device is to be disconnected.

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
Reviewed-by: Simon Glass <sjg at chromium.org>
---
 lib/efi_loader/efi_disk.c | 88 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index 243cd0e215d4..7abe5d3a6bd2 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -630,6 +630,87 @@ static int efi_disk_probe(void *ctx, struct event *event)
 	return 0;
 }
 
+/*
+ * Delete an efi_disk object for a whole raw disk
+ *
+ * @dev		uclass device (UCLASS_BLK)
+ *
+ * Delete an efi_disk object which is associated with @dev.
+ * The type of @dev must be UCLASS_BLK.
+ *
+ * @return	0 on success, -1 otherwise
+ */
+static int efi_disk_delete_raw(struct udevice *dev)
+{
+	efi_handle_t handle;
+	struct efi_disk_obj *diskobj;
+
+	if (dev_tag_get_ptr(dev, DM_TAG_EFI, (void **)&handle))
+		return -1;
+
+	diskobj = container_of(handle, struct efi_disk_obj, header);
+	efi_free_pool(diskobj->dp);
+
+	efi_delete_handle(handle);
+	dev_tag_del(dev, DM_TAG_EFI);
+
+	return 0;
+}
+
+/*
+ * Delete an efi_disk object for a disk partition
+ *
+ * @dev		uclass device (UCLASS_PARTITION)
+ *
+ * Delete an efi_disk object which is associated with @dev.
+ * The type of @dev must be UCLASS_PARTITION.
+ *
+ * @return	0 on success, -1 otherwise
+ */
+static int efi_disk_delete_part(struct udevice *dev)
+{
+	efi_handle_t handle;
+	struct efi_disk_obj *diskobj;
+
+	if (dev_tag_get_ptr(dev, DM_TAG_EFI, (void **)&handle))
+		return -1;
+
+	diskobj = container_of(handle, struct efi_disk_obj, header);
+
+	efi_free_pool(diskobj->dp);
+	efi_delete_handle(handle);
+	dev_tag_del(dev, DM_TAG_EFI);
+
+	return 0;
+}
+
+/*
+ * Delete an efi_disk object for a block device
+ *
+ * @dev		uclass device (UCLASS_BLK or UCLASS_PARTITION)
+ *
+ * Delete an efi_disk object which is associated with @dev.
+ * The type of @dev must be either UCLASS_BLK or UCLASS_PARTITION.
+ * This function is expected to be called at EV_PM_PRE_REMOVE.
+ *
+ * @return	0 on success, -1 otherwise
+ */
+static int efi_disk_remove(void *ctx, struct event *event)
+{
+	enum uclass_id id;
+	struct udevice *dev;
+
+	dev = event->data.dm.dev;
+	id = device_get_uclass_id(dev);
+
+	if (id == UCLASS_BLK)
+		return efi_disk_delete_raw(dev);
+	else if (id == UCLASS_PARTITION)
+		return efi_disk_delete_part(dev);
+	else
+		return 0;
+}
+
 efi_status_t efi_disk_init(void)
 {
 	int ret;
@@ -641,6 +722,13 @@ efi_status_t efi_disk_init(void)
 		return EFI_OUT_OF_RESOURCES;
 	}
 
+	ret = event_register("efi_disk del", EVT_DM_PRE_REMOVE,
+			     efi_disk_remove, NULL);
+	if (ret) {
+		log_err("Event registration for efi_disk del failed\n");
+		return EFI_OUT_OF_RESOURCES;
+	}
+
 	return EFI_SUCCESS;
 }
 
-- 
2.33.0