[U-Boot] [RFC 3/6] efi_loader: support convert_pointer at runtime
Heinrich Schuchardt
xypron.glpk at gmx.de
Mon Jun 17 05:41:30 UTC 2019
On 6/17/19 3:15 AM, AKASHI Takahiro wrote:
> On Sat, Jun 15, 2019 at 09:41:31PM +0200, Heinrich Schuchardt wrote:
>> On 6/5/19 6:21 AM, AKASHI Takahiro wrote:
>>> With this patch, ConvertPointer runtime service is enabled.
>>> This function will be useful only after SetVirtualAddressMap is called
>>> and before it exits according to UEFI specification.
>>
>> ConvertPointer() is called by drivers upon calling the notification
>> functions of events registered as EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE.
>>
>> We still lack support for these events.
>
> So? What do you want me to do here?
We will have to address this in a future patch.
Regards Heinrich
>
>>>
>>> Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
>>> ---
>>> lib/efi_loader/Kconfig | 8 ++++
>>> lib/efi_loader/efi_runtime.c | 81 ++++++++++++++++++++++++++----------
>>> 2 files changed, 66 insertions(+), 23 deletions(-)
>>>
>>> diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
>>> index bb9c7582b14d..e2ef43157568 100644
>>> --- a/lib/efi_loader/Kconfig
>>> +++ b/lib/efi_loader/Kconfig
>>> @@ -51,6 +51,14 @@ config EFI_RUNTIME_SET_VIRTUAL_ADDRESS_MAP
>>> Enable SetVirtualAddressMap runtime service. This API will be
>>> called by OS just before it enters into virtual address mode.
>>>
>>> +config EFI_RUNTIME_CONVERT_POINTER
>>> + bool "runtime service: ConvertPointer"
>>> + default n
>>> + help
>>> + Enable ConvertPointer runtime service. This API will be expected
>>> + to be called by UEFI drivers in relocating themselves to virtual
>>> + address space.
>>> +
>>> config EFI_DEVICE_PATH_TO_TEXT
>>> bool "Device path to text protocol"
>>> default y
>>> diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
>>> index cf202bb9ec07..ff3684a4b692 100644
>>> --- a/lib/efi_loader/efi_runtime.c
>>> +++ b/lib/efi_loader/efi_runtime.c
>>> @@ -27,7 +27,6 @@ LIST_HEAD(efi_runtime_mmio);
>>>
>>> static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void);
>>> static efi_status_t __efi_runtime EFIAPI efi_device_error(void);
>>> -static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void);
>>>
>>> /*
>>> * TODO(sjg at chromium.org): These defines and structures should come from the ELF
>>> @@ -108,6 +107,10 @@ efi_status_t efi_init_runtime_supported(void)
>>> efi_runtime_services_supported |=
>>> EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP;
>>> #endif
>>> +#ifdef CONFIG_EFI_RUNTIME_CONVERT_POINTER
>>> + efi_runtime_services_supported |=
>>> + EFI_RT_SUPPORTED_CONVERT_POINTER;
>>> +#endif
>>>
>>> return EFI_CALL(efi_set_variable(L"RuntimeServicesSupported",
>>> &efi_global_variable_guid,
>>> @@ -392,6 +395,39 @@ efi_status_t __weak __efi_runtime EFIAPI efi_set_time(struct efi_time *time)
>>> return EFI_UNSUPPORTED;
>>> }
>>>
>>> +#ifdef CONFIG_EFI_RUNTIME_CONVERT_POINTER
>>> +static struct efi_mem_desc *efi_virtmap __efi_runtime_data;
>>> +static int efi_virtmap_num __efi_runtime_data;
>>> +
>>
>> Please, put a description of the function and its parameters here.
>
> Okay.
>
>>> +static efi_status_t __efi_runtime EFIAPI efi_convert_pointer(unsigned long dbg,
>>> + void **address)
>>> +{
>>> + struct efi_mem_desc *map;
>>> + efi_physical_addr_t addr;
>>> + int i;
>>> +
>>> + if (!efi_virtmap)
>>> + return EFI_UNSUPPORTED;
>>> +
>>> + if (!address)
>>> + return EFI_INVALID_PARAMETER;
>>> +
>>> + for (i = 0, map = efi_virtmap; i < efi_virtmap_num; i++, map++) {
>>> + addr = (efi_physical_addr_t)*address;
>> This line should be before the loop.
>>
>>> + if (addr >= map->physical_start &&
>>> + (addr < (map->physical_start
>>
>> %s/(addr/addr/ No need for that extra parenthesis.
>>
>>> + + (map->num_pages << EFI_PAGE_SHIFT)))) {
>>> + *address = (void *)map->virtual_start;
>>
>> I guess on 32bit this will end in a warning? Wouldn't you need to
>> convert to uintptr_t first?
>>
>>> + *address += addr - map->physical_start;
>>
>> I think a single assignment is enough. Here you are updating a 32bit
>> pointer with the difference of two u64. I would expect a warning.
>
> I will check.
>
>> *address = (void *)(uintptr_t)
>> (addr - map->physical_start + map->virtual_start);
>>
>> Or do all calculation with addr before copying to *address.
>>
>>> +
>>> + return EFI_SUCCESS;
>>> + }
>>> + }
>>> +
>>> + return EFI_NOT_FOUND;
>>> +}
>>> +#endif
>>> +
>>> struct efi_runtime_detach_list_struct {
>>> void *ptr;
>>> void *patchto;
>>> @@ -599,6 +635,10 @@ static efi_status_t EFIAPI efi_set_virtual_address_map(
>>> return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> }
>>>
>>> + efi_virtmap = virtmap;
>>> + efi_virtmap_num = n;
>>> +
>>> +#if 0 /* FIXME: This code is fragile as calloc is used in add_runtime_mmio */
>>> /* Rebind mmio pointers */
>>> for (i = 0; i < n; i++) {
>>> struct efi_mem_desc *map = (void*)virtmap +
>>> @@ -622,14 +662,14 @@ static efi_status_t EFIAPI efi_set_virtual_address_map(
>>> *lmmio->ptr = (void *)new_addr;
>>> }
>>> }
>>> - if ((map_start <= (uintptr_t)systab.tables) &&
>>> - (map_end >= (uintptr_t)systab.tables)) {
>>> - char *ptr = (char *)systab.tables;
>>> -
>>> - ptr += off;
>>> - systab.tables = (struct efi_configuration_table *)ptr;
>>> - }
>>
>> This looks like an unrelated change.
>
> It does.
> This code should be replaced by:
>>> + /* FIXME */
>>> + efi_convert_pointer(0, (void **)&systab.tables);
>
> -Takahiro Akashi
>
>> Put it into a separate patch, please.
>>
>> Best regards
>>
>> Heinrich
>>
>>> }
>>> +#endif
>>> +
>>> + /* FIXME */
>>> + efi_convert_pointer(0, (void **)&systab.tables);
>>> +
>>> + /* All fixes must be done before this line */
>>> + efi_virtmap = NULL;
>>>
>>> /* Move the actual runtime code over */
>>> for (i = 0; i < n; i++) {
>>> @@ -644,6 +684,11 @@ static efi_status_t EFIAPI efi_set_virtual_address_map(
>>> /* Once we're virtual, we can no longer handle
>>> complex callbacks */
>>> efi_runtime_detach(new_offset);
>>> +
>>> + /*
>>> + * FIXME:
>>> + * We can no longer update RuntimeServicesSupported.
>>> + */
>>> return EFI_EXIT(EFI_SUCCESS);
>>> }
>>> }
>>> @@ -733,20 +778,6 @@ static efi_status_t __efi_runtime EFIAPI efi_device_error(void)
>>> return EFI_DEVICE_ERROR;
>>> }
>>>
>>> -/**
>>> - * efi_invalid_parameter() - replacement function, returns EFI_INVALID_PARAMETER
>>> - *
>>> - * This function is used after SetVirtualAddressMap() is called as replacement
>>> - * for services that are not available anymore due to constraints of the U-Boot
>>> - * implementation.
>>> - *
>>> - * Return: EFI_INVALID_PARAMETER
>>> - */
>>> -static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void)
>>> -{
>>> - return EFI_INVALID_PARAMETER;
>>> -}
>>> -
>>> /**
>>> * efi_update_capsule() - process information from operating system
>>> *
>>> @@ -833,7 +864,11 @@ struct efi_runtime_services __efi_runtime_data efi_runtime_services = {
>>> #else
>>> .set_virtual_address_map = (void *)&efi_unimplemented,
>>> #endif
>>> - .convert_pointer = (void *)&efi_invalid_parameter,
>>> +#ifdef CONFIG_EFI_RUNTIME_CONVERT_POINTER
>>> + .convert_pointer = &efi_convert_pointer,
>>> +#else
>>> + .convert_pointer = (void *)&efi_unimplemented,
>>
>> I feel uneasy using a function efi_unimplemented() with a different
>> number of parameters here. Depending on the ABI this may lead to a crash.
>>
>> Best regards
>>
>> Heinrich
>>
>>> +#endif
>>> .get_variable = efi_get_variable,
>>> .get_next_variable_name = efi_get_next_variable_name,
>>> .set_variable = efi_set_variable,
>>>
>>
>
More information about the U-Boot
mailing list