Re: [PATCH hurd] rumpdisk: Include complete USB stack to enable mass storage driver

[Samuel Thibault]

Damien Zammit, le dim. 25 juin 2023 12:35:51 +0000, a ecrit:
> This simple change allows hurd to be bootable off usb!

Well, yes and no :)

We also need /dev entries. It happens that this re-uses /dev/sd*
names, so we need to care about compatibility. We probably want
rumpdisk_device_open to forward to the kernel when 'disabled' is true.

> It is not ideal to have entire usb stack with the mass storage driver
> and combined with SATA, but there is no easy way to separate
> the usb stack into host/device yet.

Ok, but can't we build a separate rumpusbdisk that only has the USB
drivers? Each process (SATA+IDE and USB) can easily drive its own PCI
card.

> Caveats: USB seems to share IRQs with network device,
> which does not seem to work well currently.
> I am not sure of the status of irq sharing but it seems broken.

That was supposed to be working, but evil lies in the details as usual.

> ---
>  rumpdisk/Makefile     | 2 +-
>  rumpdisk/block-rump.c | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/rumpdisk/Makefile b/rumpdisk/Makefile
> index b59aaf9a..9ee8a1d3 100644
> --- a/rumpdisk/Makefile
> +++ b/rumpdisk/Makefile
> @@ -15,7 +15,7 @@
>  #   along with this program; if not, write to the Free Software
>  #   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
>  
> -RUMPLIBS=rump rumpuser rumpdev rumpdev_disk rumpdev_pci rumpvfs 
> rumpdev_ahcisata rumpdev_piixide rumpdev_ata
> +RUMPLIBS=rump rumpuser rumpdev rumpdev_disk rumpdev_pci rumpvfs 
> rumpdev_ahcisata rumpdev_piixide rumpdev_ata rumpdev_usb rumpdev_pci_usbhc 
> rumpdev_umass
>  RUMPEXTRA=rumpdev_scsipi
>  
>  # If we have a configured tree, include the configuration so that we
> diff --git a/rumpdisk/block-rump.c b/rumpdisk/block-rump.c
> index 5ceb14ae..0a8cbe44 100644
> --- a/rumpdisk/block-rump.c
> +++ b/rumpdisk/block-rump.c
> @@ -46,7 +46,7 @@
>  #define BLKRRPART  0x125F     /* re-read partition table */
>  
>  #define DISK_NAME_LEN 32
> -#define MAX_DISK_DEV 2
> +#define MAX_DISK_DEV 3
>  
>  static bool disabled;
>  
> @@ -108,6 +108,7 @@ is_disk_device (const char *name)
>    const char *dev;
>    const char *allowed_devs[MAX_DISK_DEV] = {
>      "wd",
> +    "sd",
>      "cd"
>    };
>    uint8_t i;
> -- 
> 2.40.1