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

Heinrich Schuchardt
2018-12-11T19:55:41Z

On 11/15/18 5:58 AM, AKASHI Takahiro wrote:
> 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>

Why should we try to fix something in the EFI subsystems that goes wrong
in the handling of device enumeration.

@Marek
Why should a 'usb start' command be needed to make a plugged in device
available?

Best regards

Heirnich

> ---
> 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;
> +}
>