diff options
| -rw-r--r-- | src/drivers/net/efi/snponly.c | 112 |
1 files changed, 70 insertions, 42 deletions
diff --git a/src/drivers/net/efi/snponly.c b/src/drivers/net/efi/snponly.c index 674e0a050..163704636 100644 --- a/src/drivers/net/efi/snponly.c +++ b/src/drivers/net/efi/snponly.c @@ -45,14 +45,23 @@ struct chained_protocol { /** Protocol GUID */ EFI_GUID *protocol; /** - * Protocol instance installed on the loaded image's device handle + * Target device handle + * + * This is the uppermost handle on which the same protocol + * instance is installed as we find on the loaded image's + * device handle. * * We match against the protocol instance (rather than simply * matching against the device handle itself) because some * systems load us via a child of the underlying device, with * a duplicate protocol installed on the child handle. + * + * We record the handle rather than the protocol instance + * pointer since the calls to DisconnectController() and + * ConnectController() may end up uninstalling and + * reinstalling the protocol instance. */ - void *interface; + EFI_HANDLE device; }; /** Chainloaded SNP protocol */ @@ -66,49 +75,68 @@ static struct chained_protocol chained_nii = { }; /** - * Locate chainloaded protocol instance + * Locate chainloaded protocol * * @v chained Chainloaded protocol - * @ret rc Return status code */ -static int chained_locate ( struct chained_protocol *chained ) { +static void chained_locate ( struct chained_protocol *chained ) { EFI_BOOT_SERVICES *bs = efi_systab->BootServices; EFI_HANDLE device = efi_loaded_image->DeviceHandle; - EFI_HANDLE parent; + EFI_HANDLE handle; + void *match = NULL; + void *interface; + unsigned int skip; EFI_STATUS efirc; int rc; - /* Locate handle supporting this protocol */ - if ( ( rc = efi_locate_device ( device, chained->protocol, - &parent, 0 ) ) != 0 ) { - DBGC ( device, "CHAINED %s does not support %s: %s\n", - efi_handle_name ( device ), - efi_guid_ntoa ( chained->protocol ), strerror ( rc ) ); - goto err_locate_device; - } - DBGC ( device, "CHAINED %s found %s on ", efi_handle_name ( device ), - efi_guid_ntoa ( chained->protocol ) ); - DBGC ( device, "%s\n", efi_handle_name ( parent ) ); - - /* Get protocol instance */ - if ( ( efirc = bs->OpenProtocol ( parent, chained->protocol, - &chained->interface, efi_image_handle, - device, - EFI_OPEN_PROTOCOL_GET_PROTOCOL ))!=0){ - rc = -EEFI ( efirc ); - DBGC ( device, "CHAINED %s could not open %s on ", + /* Identify target device handle */ + for ( skip = 0 ; ; skip++ ) { + + /* Locate handle supporting this protocol */ + if ( ( rc = efi_locate_device ( device, chained->protocol, + &handle, skip ) ) != 0 ) { + if ( skip == 0 ) { + DBGC ( device, "CHAINED %s does not support " + "%s: %s\n", efi_handle_name ( device ), + efi_guid_ntoa ( chained->protocol ), + strerror ( rc ) ); + } + break; + } + + /* Get protocol instance */ + if ( ( efirc = bs->OpenProtocol ( + handle, chained->protocol, &interface, + efi_image_handle, handle, + EFI_OPEN_PROTOCOL_GET_PROTOCOL )) != 0){ + rc = -EEFI ( efirc ); + DBGC ( device, "CHAINED %s could not open %s on ", + efi_handle_name ( device ), + efi_guid_ntoa ( chained->protocol ) ); + DBGC ( device, "%s: %s\n", + efi_handle_name ( handle ), strerror ( rc ) ); + break; + } + bs->CloseProtocol ( handle, chained->protocol, + efi_image_handle, handle ); + + /* Stop if we reach a non-matching protocol instance */ + if ( match && ( match != interface ) ) { + DBGC ( device, "CHAINED %s found non-matching %s on ", + efi_handle_name ( device ), + efi_guid_ntoa ( chained->protocol ) ); + DBGC ( device, "%s\n", efi_handle_name ( handle ) ); + break; + } + + /* Record this handle */ + chained->device = handle; + match = interface; + DBGC ( device, "CHAINED %s found %s on ", efi_handle_name ( device ), efi_guid_ntoa ( chained->protocol ) ); - DBGC ( device, "%s: %s\n", - efi_handle_name ( parent ), strerror ( rc ) ); - goto err_open_protocol; + DBGC ( device, "%s\n", efi_handle_name ( chained->device ) ); } - - err_locate_device: - bs->CloseProtocol ( parent, chained->protocol, efi_image_handle, - device ); - err_open_protocol: - return rc; } /** @@ -121,8 +149,8 @@ static int chained_locate ( struct chained_protocol *chained ) { static int chained_supported ( EFI_HANDLE device, struct chained_protocol *chained ) { EFI_BOOT_SERVICES *bs = efi_systab->BootServices; - EFI_STATUS efirc; void *interface; + EFI_STATUS efirc; int rc; /* Get protocol */ @@ -136,19 +164,19 @@ static int chained_supported ( EFI_HANDLE device, goto err_open_protocol; } - /* Test for a match against the chainloading device */ - if ( interface != chained->interface ) { - DBGC ( device, "CHAINED %s %p is not the chainloaded %s\n", - efi_handle_name ( device ), interface, - efi_guid_ntoa ( chained->protocol ) ); + /* Ignore non-matching handles */ + if ( device != chained->device ) { + DBGC2 ( device, "CHAINED %s is not the chainloaded %s\n", + efi_handle_name ( device ), + efi_guid_ntoa ( chained->protocol ) ); rc = -ENOTTY; goto err_no_match; } /* Success */ rc = 0; - DBGC ( device, "CHAINED %s %p is the chainloaded %s\n", - efi_handle_name ( device ), interface, + DBGC ( device, "CHAINED %s is the chainloaded %s\n", + efi_handle_name ( device ), efi_guid_ntoa ( chained->protocol ) ); err_no_match: |