[U-Boot] [PATCH v2 2/3] efi_loader: enumerate disk devices every time

AKASHI Takahiro
2018-11-15T04:58:09Z

Currently, efi_init_obj_list() scan disk devices only once, and never
change a list of efi disk devices. This will possibly result in failing
to find a removable storage which may be added later on. See [1].

In this patch, called is efi_disk_update() which is responsible for
re-scanning UCLASS_BLK devices and removing/adding efi disks if necessary.

For example,

=> efishell devices
Scanning disk pci_mmc.blk...
Found 3 disks
Device Name
============================================
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(0)/SD(0)
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(0)/SD(0)/HD(2,MBR,0x086246ba,0x40800,0x3f800)
=> usb start
starting USB...
USB0: USB EHCI 1.00
scanning bus 0 for devices... 3 USB Device(s) found
scanning usb for storage devices... 1 Storage Device(s) found
=> efishell devices
Scanning disk usb_mass_storage.lun0...
Device Name
============================================
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(0)/SD(0)
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/SD(0)/SD(0)/HD(2,MBR,0x086246ba,0x40800,0x3f800)
/VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/USBClass(0,0,9,0,1)/USBClass(46f4,1,0,0,0)/HD(1,0x01,0,0x40,0x14fe4c)

Without this patch, the last device, USB mass storage, won't show up.

[1] https://lists.denx.de/pipermail/u-boot/2018-October/345307.html

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
cmd/bootefi.c | 17 +++-
include/efi_loader.h | 4 +
lib/efi_loader/efi_disk.c | 191 ++++++++++++++++++++++++++++++++++++++
3 files changed, 210 insertions(+), 2 deletions(-)

diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index 3cefb4d0ecaa..82649e211fda 100644
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -56,9 +56,22 @@ efi_status_t efi_init_obj_list(void)
*/
efi_save_gd();

- /* Initialize once only */
- if (efi_obj_list_initialized != OBJ_LIST_NOT_INITIALIZED)
+ if (efi_obj_list_initialized == EFI_SUCCESS) {
+#ifdef CONFIG_PARTITIONS
+ ret = efi_disk_update();
+ if (ret != EFI_SUCCESS)
+ printf("+++ updating disks list failed\n");
+
+ /*
+ * It may sound odd, but most part of EFI should
+ * yet work.
+ */
+#endif
return efi_obj_list_initialized;
+ } else if (efi_obj_list_initialized != OBJ_LIST_NOT_INITIALIZED) {
+ /* Initialize once only */
+ return efi_obj_list_initialized;
+ }

/* Initialize system table */
ret = efi_initialize_system_table();
diff --git a/include/efi_loader.h b/include/efi_loader.h
index 5cc3bded03fa..3bae1844befb 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -260,6 +260,10 @@ efi_status_t efi_initialize_system_table(void);
efi_status_t efi_console_register(void);
/* Called by bootefi to make all disk storage accessible as EFI objects */
efi_status_t efi_disk_register(void);
+/* Check validity of efi disk */
+bool efi_disk_is_valid(efi_handle_t handle);
+/* Called by bootefi to find and update disk storage information */
+efi_status_t efi_disk_update(void);
/* Create handles and protocols for the partitions of a block device */
int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
const char *if_typename, int diskid,
diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index c037526ad2d0..0c4d79ee3fc9 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -14,10 +14,14 @@

const efi_guid_t efi_block_io_guid = BLOCK_IO_GUID;

+#define _EFI_DISK_FLAG_DELETED 0x1 /* to be removed */
+#define _EFI_DISK_FLAG_INVALID 0x80000000 /* in stale state */
+
/**
* struct efi_disk_obj - EFI disk object
*
* @header: EFI object header
+ * @flags: control flags
* @ops: EFI disk I/O protocol interface
* @ifname: interface name for block device
* @dev_index: device index of block device
@@ -30,6 +34,7 @@ const efi_guid_t efi_block_io_guid = BLOCK_IO_GUID;
*/
struct efi_disk_obj {
struct efi_object header;
+ int flags;
struct efi_block_io ops;
const char *ifname;
int dev_index;
@@ -41,6 +46,35 @@ struct efi_disk_obj {
struct blk_desc *desc;
};

+static void efi_disk_mark_deleted(struct efi_disk_obj *disk)
+{
+ disk->flags |= _EFI_DISK_FLAG_DELETED;
+}
+
+static void efi_disk_clear_deleted(struct efi_disk_obj *disk)
+{
+ disk->flags &= ~_EFI_DISK_FLAG_DELETED;
+}
+
+static bool efi_disk_deleted_marked(struct efi_disk_obj *disk)
+{
+ return disk->flags & _EFI_DISK_FLAG_DELETED;
+}
+
+static void efi_disk_mark_invalid(struct efi_disk_obj *disk)
+{
+ disk->flags |= _EFI_DISK_FLAG_INVALID;
+}
+
+bool efi_disk_is_valid(efi_handle_t handle)
+{
+ struct efi_disk_obj *disk;
+
+ disk = container_of(handle, struct efi_disk_obj, header);
+
+ return !(disk->flags & _EFI_DISK_FLAG_INVALID);
+}
+
static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
char extended_verification)
{
@@ -64,6 +98,9 @@ static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
unsigned long n;

diskobj = container_of(this, struct efi_disk_obj, ops);
+ if (diskobj->flags & _EFI_DISK_FLAG_INVALID)
+ return EFI_DEVICE_ERROR;
+
desc = (struct blk_desc *) diskobj->desc;
blksz = desc->blksz;
blocks = buffer_size / blksz;
@@ -440,3 +477,157 @@ efi_status_t efi_disk_register(void)

return EFI_SUCCESS;
}
+
+/*
+ * Mark all the block devices as "deleted," and return an array of
+ * handles for later use. It should be freed in a caller.
+ */
+static efi_status_t efi_disk_mark_deleted_all(efi_handle_t **handlesp)
+{
+ efi_handle_t *handles = NULL;
+ efi_uintn_t size = 0;
+ int num, i;
+ struct efi_disk_obj *disk;
+ efi_status_t ret;
+
+ ret = efi_locate_handle(BY_PROTOCOL, &efi_block_io_guid, NULL,
+ &size, handles);
+ if (ret == EFI_BUFFER_TOO_SMALL) {
+ handles = calloc(1, size);
+ if (!handles)
+ return EFI_OUT_OF_RESOURCES;
+
+ ret = efi_locate_handle(BY_PROTOCOL, &efi_block_io_guid, NULL,
+ &size, handles);
+ }
+ if (ret != EFI_SUCCESS) {
+ free(handles);
+ return ret;
+ }
+
+ num = size / sizeof(*handles);
+ for (i = 0; i < num; i++) {
+ disk = container_of(handles[i], struct efi_disk_obj, header);
+ efi_disk_mark_deleted(disk);
+ }
+
+ *handlesp = handles;
+
+ return num;
+}
+
+/*
+ * Clear "deleted" flag for a block device which is identified with desc.
+ * If desc is NULL, clear all devices.
+ *
+ * Return a number of disks cleared.
+ */
+static int efi_disk_clear_deleted_matched(struct blk_desc *desc,
+ efi_handle_t *handles, int num)
+{
+ struct efi_disk_obj *disk;
+ int disks, i;
+
+ for (i = 0, disks = 0; i < num; i++) {
+ disk = container_of(handles[i], struct efi_disk_obj, header);
+
+ if (!desc || disk->desc == desc) {
+ efi_disk_clear_deleted(disk);
+ disks++;
+ }
+ }
+
+ return disks;
+}
+
+/*
+ * Do delete all the block devices marked as "deleted"
+ */
+static efi_status_t efi_disk_do_delete(efi_handle_t *handles, int num)
+{
+ struct efi_disk_obj *disk;
+ int i;
+
+ for (i = 0; i < num; i++) {
+ disk = container_of(handles[i], struct efi_disk_obj, header);
+
+ if (!efi_disk_deleted_marked(disk))
+ continue;
+
+ efi_disk_mark_invalid(disk);
+ /*
+ * TODO:
+ * efi_delete_handle(handles[i]);
+ */
+ }
+
+ return EFI_SUCCESS;
+}
+
+/*
+ * efi_disk_update - recreate efi disk mappings after initialization
+ *
+ * @return efi error code
+ */
+efi_status_t efi_disk_update(void)
+{
+#ifdef CONFIG_BLK
+ efi_handle_t *handles = NULL;
+ struct udevice *dev;
+ struct blk_desc *desc;
+ const char *if_typename;
+ struct efi_disk_obj *disk;
+ int n, disks = 0;
+ efi_status_t ret;
+
+ /* temporarily mark all the devices "deleted" */
+ ret = efi_disk_mark_deleted_all(&handles);
+ if (ret & EFI_ERROR_MASK) {
+ printf("ERROR: Failed to rescan block devices.\n");
+ return ret;
+ }
+
+ n = (int)ret;
+ for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
+ uclass_next_device_check(&dev)) {
+ desc = dev_get_uclass_platdata(dev);
+ if (n && efi_disk_clear_deleted_matched(desc, handles, n))
+ /* existing device */
+ continue;
+
+ /* new device */
+ if_typename = blk_get_if_type_name(desc->if_type);
+
+ /* Add block device for the full device */
+ printf("Scanning disk %s...\n", dev->name);
+ ret = efi_disk_add_dev(NULL, NULL, if_typename,
+ desc, desc->devnum, 0, 0, &disk);
+ if (ret == EFI_NOT_READY) {
+ printf("Disk %s not ready\n", dev->name);
+ continue;
+ }
+ if (ret != EFI_SUCCESS) {
+ printf("ERROR: failure to add disk device %s, r = %lu\n",
+ dev->name, ret & ~EFI_ERROR_MASK);
+ continue;
+ }
+ disks++;
+
+ /* Partitions show up as block devices in EFI */
+ disks += efi_disk_create_partitions(&disk->header, desc,
+ if_typename,
+ desc->devnum, dev->name);
+ }
+
+ if (n) {
+ /* do delete "deleted" disks */
+ ret = efi_disk_do_delete(handles, n);
+
+ /* undo marking */
+ efi_disk_clear_deleted_matched(NULL, handles, n);
+
+ free(handles);
+ }
+#endif
+ return EFI_SUCCESS;
+}
--
2.19.0