On Mon, 2013-04-15 at 13:09 -0700, Matthew Garrett wrote:
> EFI variables can be flagged as being accessible only within boot services.
> This makes it awkward for us to figure out how much space they use at
> runtime. In theory we could figure this out by simply comparing the results
> from QueryVariableInfo() to the space used by all of our variables, but
> that fails if the platform doesn't garbage collect on every boot. Thankfully,
> calling QueryVariableInfo() while still inside boot services gives a more
> reliable answer. This patch passes that information from the EFI boot stub
> up to the efi platform code.
>
> Signed-off-by: Matthew Garrett <matthew.garr...@nebula.com>
This seems to be the patch that has become commit
cc5a080c5d40c36089bb08a8a16fa3fc7047fe0f ("efi: Pass boot services
variable info to runtime code"), which is part of v3.9-rc8.
It triggers this GCC warning (on Fedora 17, 32 bit):
arch/x86/boot/compressed/eboot.c: In function ‘setup_efi_vars’:
arch/x86/boot/compressed/eboot.c:269:2: warning: passing argument 1 of
‘efi_call_phys’ makes pointer from integer without a cast [enabled by default]
In file included from arch/x86/boot/compressed/eboot.c:12:0:
[...]/arch/x86/include/asm/efi.h:8:33: note: expected ‘void *’ but argument
is of type ‘long unsigned int’
> --- a/arch/x86/boot/compressed/eboot.c
> +++ b/arch/x86/boot/compressed/eboot.c
> @@ -251,6 +251,51 @@ static void find_bits(unsigned long mask, u8 *pos, u8
> *size)
> *size = len;
> }
>
> +static efi_status_t setup_efi_vars(struct boot_params *params)
> +{
> + struct setup_data *data;
> + struct efi_var_bootdata *efidata;
> + u64 store_size, remaining_size, var_size;
> + efi_status_t status;
> +
> + if (!sys_table->runtime->query_variable_info)
> + return EFI_UNSUPPORTED;
> +
> + data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
> +
> + while (data && data->next)
> + data = (struct setup_data *)(unsigned long)data->next;
> +
> + status = efi_call_phys4(sys_table->runtime->query_variable_info,
Casting to void * here makes the warning go away. But the code is
sufficiently complicated (for me) to make it unobvious whether that is
the right thing to do. Besides, I don't think I have hardware to test
this.
> + EFI_VARIABLE_NON_VOLATILE |
> + EFI_VARIABLE_BOOTSERVICE_ACCESS |
> + EFI_VARIABLE_RUNTIME_ACCESS, &store_size,
> + &remaining_size, &var_size);
> +
> + if (status != EFI_SUCCESS)
> + return status;
> +
> + status = efi_call_phys3(sys_table->boottime->allocate_pool,
> + EFI_LOADER_DATA, sizeof(*efidata), &efidata);
> +
> + if (status != EFI_SUCCESS)
> + return status;
> +
> + efidata->data.type = SETUP_EFI_VARS;
> + efidata->data.len = sizeof(struct efi_var_bootdata) -
> + sizeof(struct setup_data);
> + efidata->data.next = 0;
> + efidata->store_size = store_size;
> + efidata->remaining_size = remaining_size;
> + efidata->max_var_size = var_size;
> +
> + if (data)
> + data->next = (unsigned long)efidata;
> + else
> + params->hdr.setup_data = (unsigned long)efidata;
> +
> +}
> +
> static efi_status_t setup_efi_pci(struct boot_params *params)
> {
> efi_pci_io_protocol *pci;
Paul Bolle
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
