diff options
| author | Michael Brown <mcb30@ipxe.org> | 2024-03-05 20:00:15 +0000 |
|---|---|---|
| committer | Michael Brown <mcb30@ipxe.org> | 2024-03-06 16:11:29 +0000 |
| commit | c4471e3408d85c51a69991974985fe283d869eac (patch) | |
| tree | c3e24fa6bb2386dbbcf19993e26dc8ba1b29b685 | |
| parent | 636ccb4ca55c73841e634f9d5986087fb3565da4 (diff) | |
| download | ipxe-c4471e3408d85c51a69991974985fe283d869eac.tar.gz | |
[efi] Add efi_path_guid() utility function
EFI provides no API for determining the partition GUID (if any) for a
specified device handle. The partition GUID appears to be exposed
only as part of the device path.
Add efi_path_guid() to extract the partition GUID (if any) from a
device path.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
| -rw-r--r-- | src/include/ipxe/efi/efi_path.h | 2 | ||||
| -rw-r--r-- | src/include/ipxe/errfile.h | 1 | ||||
| -rw-r--r-- | src/interface/efi/efi_path.c | 43 |
3 files changed, 46 insertions, 0 deletions
diff --git a/src/include/ipxe/efi/efi_path.h b/src/include/ipxe/efi/efi_path.h index e75ae42c4..20ff43f64 100644 --- a/src/include/ipxe/efi/efi_path.h +++ b/src/include/ipxe/efi/efi_path.h @@ -20,6 +20,7 @@ struct aoe_device; struct fcp_description; struct ib_srp_device; struct usb_function; +union uuid; /** * Terminate device path @@ -43,6 +44,7 @@ extern EFI_DEVICE_PATH_PROTOCOL * efi_path_end ( EFI_DEVICE_PATH_PROTOCOL *path ); extern size_t efi_path_len ( EFI_DEVICE_PATH_PROTOCOL *path ); extern unsigned int efi_path_vlan ( EFI_DEVICE_PATH_PROTOCOL *path ); +extern int efi_path_guid ( EFI_DEVICE_PATH_PROTOCOL *path, union uuid *uuid ); extern EFI_DEVICE_PATH_PROTOCOL * efi_paths ( EFI_DEVICE_PATH_PROTOCOL *first, ... ); extern EFI_DEVICE_PATH_PROTOCOL * efi_netdev_path ( struct net_device *netdev ); diff --git a/src/include/ipxe/errfile.h b/src/include/ipxe/errfile.h index 7cff594d5..1fe34113d 100644 --- a/src/include/ipxe/errfile.h +++ b/src/include/ipxe/errfile.h @@ -80,6 +80,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); #define ERRFILE_acpimac ( ERRFILE_CORE | 0x00280000 ) #define ERRFILE_efi_strings ( ERRFILE_CORE | 0x00290000 ) #define ERRFILE_uuid ( ERRFILE_CORE | 0x002a0000 ) +#define ERRFILE_efi_path ( ERRFILE_CORE | 0x002b0000 ) #define ERRFILE_eisa ( ERRFILE_DRIVER | 0x00000000 ) #define ERRFILE_isa ( ERRFILE_DRIVER | 0x00010000 ) diff --git a/src/interface/efi/efi_path.c b/src/interface/efi/efi_path.c index a78f97fce..d1e22eeaa 100644 --- a/src/interface/efi/efi_path.c +++ b/src/interface/efi/efi_path.c @@ -22,9 +22,11 @@ FILE_LICENCE ( GPL2_OR_LATER ); #include <stdlib.h> #include <stdarg.h> #include <string.h> +#include <errno.h> #include <byteswap.h> #include <ipxe/netdevice.h> #include <ipxe/vlan.h> +#include <ipxe/uuid.h> #include <ipxe/tcpip.h> #include <ipxe/uri.h> #include <ipxe/iscsi.h> @@ -133,6 +135,47 @@ unsigned int efi_path_vlan ( EFI_DEVICE_PATH_PROTOCOL *path ) { } /** + * Get partition GUID from device path + * + * @v path Device path + * @v guid Partition GUID to fill in + * @ret rc Return status code + */ +int efi_path_guid ( EFI_DEVICE_PATH_PROTOCOL *path, union uuid *guid ) { + EFI_DEVICE_PATH_PROTOCOL *next; + HARDDRIVE_DEVICE_PATH *hd; + int rc; + + /* Search for most specific partition device path */ + rc = -ENOENT; + for ( ; ( next = efi_path_next ( path ) ) ; path = next ) { + + /* Skip non-harddrive device paths */ + if ( path->Type != MEDIA_DEVICE_PATH ) + continue; + if ( path->SubType != MEDIA_HARDDRIVE_DP ) + continue; + + /* Skip non-GUID signatures */ + hd = container_of ( path, HARDDRIVE_DEVICE_PATH, Header ); + if ( hd->SignatureType != SIGNATURE_TYPE_GUID ) + continue; + + /* Extract GUID */ + memcpy ( guid, hd->Signature, sizeof ( *guid ) ); + uuid_mangle ( guid ); + + /* Record success, but continue searching in case + * there exists a more specific GUID (e.g. a partition + * GUID rather than a disk GUID). + */ + rc = 0; + } + + return rc; +} + +/** * Concatenate EFI device paths * * @v ... List of device paths (NULL terminated) |