[SLOF] [PATCH v2 2/2] usb/storage: Implement block write support

[Thomas Huth]

On 2018-12-12 15:31, Laurent Vivier wrote:
> The only missing parts were to manage the transfer direction in
> do-bulk-command and to copy the data to the buffer before the
> write operation.
> 
> This is needed as GRUB2 wants to write the grubenv file at start
> and hangs because the data are not provided to the disk controller.
> 
> I've checked the file is correctly modified by modifying an environment
> variable in GRUB2 with "set saved_entry=2" then "save_env saved_entry"
> and checking the result in linux with "grub2-editenv list".
> 
> Fixes: Fixes: a0b96fe66fcd991b407c1d67ca842921e477a6fd
>        (Provide "write" function in the disk-label package)
> Signed-off-by: Laurent Vivier <lvivier at redhat.com>
> ---
>  slof/fs/usb/dev-storage.fs | 25 +++++++++++++++++++++----
>  1 file changed, 21 insertions(+), 4 deletions(-)
> 
> diff --git a/slof/fs/usb/dev-storage.fs b/slof/fs/usb/dev-storage.fs
> index fe5af1c..449659e 100644
> --- a/slof/fs/usb/dev-storage.fs
> +++ b/slof/fs/usb/dev-storage.fs
> @@ -103,7 +103,7 @@ scsi-open
>  \ if sense-len is 0 then no sense data is actually present
>  \
>  
> -: do-bulk-command ( resp-buffer resp-size -- TRUE | FALSE )
> +: do-bulk-command ( dir resp-buffer resp-size -- TRUE | FALSE )
>      TO resp-size
>      TO resp-buffer
>      udev USB_PIPE_OUT td-buf td-buf-phys dma-buf-phys usb>cmd 1F
> @@ -113,13 +113,20 @@ scsi-open
>      \ transfer CBW
>      resp-size IF
>          d# 125 us
> -        udev USB_PIPE_IN td-buf td-buf-phys resp-buffer resp-size
> +        IF
> +            udev USB_PIPE_IN
> +        ELSE
> +            udev USB_PIPE_OUT
> +        THEN
> +        td-buf td-buf-phys resp-buffer resp-size
>          usb-transfer-bulk 1 = not IF \ transfer data
>              usb-disk-debug? IF ." Data phase failed " cr THEN
>              \ FALSE EXIT
>              \ in case of a stall/halted endpoint we clear the halt
>              \ Fall through and try reading the CSW
>          THEN
> +    ELSE
> +        drop
>      THEN
>      d# 125 us
>      udev USB_PIPE_IN td-buf td-buf-phys dma-buf-phys usb>csw 0D

There is another "ELSE FALSE EXIT THEN" at the end of this function. I
think you've got to drop the "dir" stack item in that case, too, don't you?

 Thomas