[libc] Redefine low 8 bits of error code as "platform error code"

The low 8 bits of an iPXE error code are currently defined as the
closest equivalent PXE error code.  Generalise this scheme to
platforms other than PC-BIOS by extending this definition to "closest
equivalent platform error code".  This allows for the possibility of
returning meaningful errors via EFI APIs.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

2 files changed, 242 insertions, 0 deletions

diff --git a/src/include/ipxe/errno/efi.h b/src/include/ipxe/errno/efi.h
new file mode 100644
index 000000000..e4f9e5fe1
--- /dev/null
+++ b/src/include/ipxe/errno/efi.h
@@ -0,0 +1,129 @@
+#ifndef _IPXE_ERRNO_EFI_H
+#define _IPXE_ERRNO_EFI_H
+
+/**
+ * @file
+ *
+ * EFI platform error codes
+ *
+ * We derive our platform error codes from the possible values for
+ * EFI_STATUS defined in the UEFI specification.
+ *
+ * EFI_STATUS codes are 32-bit values consisting of a top bit which is
+ * set for errors and clear for warnings, and a mildly undefined
+ * code of low bits indicating the precise error/warning code.
+ * Errors and warnings have completely separate namespaces.
+ *
+ * We assume that no EFI_STATUS code will ever be defined which uses
+ * more than bits 0-6 of the low bits.  We then choose to encode our
+ * platform-specific error by mapping bit 31 of the EFI_STATUS to bit
+ * 7 of the platform-specific error code, and preserving bits 0-6
+ * as-is.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <ipxe/efi/efi.h>
+#include <ipxe/efi/Uefi/UefiBaseType.h>
+
+/**
+ * Convert platform error code to platform component of iPXE error code
+ *
+ * @v platform		Platform error code
+ * @ret errno		Platform component of iPXE error code
+ */
+#define PLATFORM_TO_ERRNO( platform ) \
+	( ( (platform) | ( (platform) >> 24 ) ) & 0xff )
+
+/**
+ * Convert iPXE error code to platform error code
+ *
+ * @v errno		iPXE error code
+ * @ret platform	Platform error code
+ */
+#define ERRNO_TO_PLATFORM( errno ) \
+	( ( ( (errno) << 24 ) | (errno) ) & 0x8000007f )
+
+/* Platform-specific error codes */
+#define PLATFORM_ENOERR		EFI_SUCCESS
+#define PLATFORM_E2BIG		EFI_BUFFER_TOO_SMALL
+#define PLATFORM_EACCES		EFI_ACCESS_DENIED
+#define PLATFORM_EADDRINUSE	EFI_ALREADY_STARTED
+#define PLATFORM_EADDRNOTAVAIL	EFI_NOT_READY
+#define PLATFORM_EAFNOSUPPORT	EFI_UNSUPPORTED
+#define PLATFORM_EAGAIN		EFI_NOT_READY
+#define PLATFORM_EALREADY	EFI_ALREADY_STARTED
+#define PLATFORM_EBADF		EFI_INVALID_PARAMETER
+#define PLATFORM_EBADMSG	EFI_PROTOCOL_ERROR
+#define PLATFORM_EBUSY		EFI_NO_RESPONSE
+#define PLATFORM_ECANCELED	EFI_ABORTED
+#define PLATFORM_ECHILD		EFI_NOT_FOUND
+#define PLATFORM_ECONNABORTED	EFI_ABORTED
+#define PLATFORM_ECONNREFUSED	EFI_NO_RESPONSE
+#define PLATFORM_ECONNRESET	EFI_ABORTED
+#define PLATFORM_EDEADLK	EFI_NOT_READY
+#define PLATFORM_EDESTADDRREQ	EFI_PROTOCOL_ERROR
+#define PLATFORM_EDOM		EFI_INVALID_PARAMETER
+#define PLATFORM_EDQUOT		EFI_VOLUME_FULL
+#define PLATFORM_EEXIST		EFI_WRITE_PROTECTED
+#define PLATFORM_EFAULT		EFI_INVALID_PARAMETER
+#define PLATFORM_EFBIG		EFI_END_OF_MEDIA
+#define PLATFORM_EHOSTUNREACH	EFI_NO_RESPONSE
+#define PLATFORM_EIDRM		EFI_INVALID_PARAMETER
+#define PLATFORM_EILSEQ		EFI_INVALID_PARAMETER
+#define PLATFORM_EINPROGRESS	EFI_ALREADY_STARTED
+#define PLATFORM_EINTR		EFI_NOT_READY
+#define PLATFORM_EINVAL		EFI_INVALID_PARAMETER
+#define PLATFORM_EIO		EFI_PROTOCOL_ERROR
+#define PLATFORM_EISCONN	EFI_ALREADY_STARTED
+#define PLATFORM_EISDIR		EFI_PROTOCOL_ERROR
+#define PLATFORM_ELOOP		EFI_VOLUME_CORRUPTED
+#define PLATFORM_EMFILE		EFI_OUT_OF_RESOURCES
+#define PLATFORM_EMLINK		EFI_OUT_OF_RESOURCES
+#define PLATFORM_EMSGSIZE	EFI_BAD_BUFFER_SIZE
+#define PLATFORM_EMULTIHOP	EFI_INVALID_PARAMETER
+#define PLATFORM_ENAMETOOLONG	EFI_INVALID_PARAMETER
+#define PLATFORM_ENETDOWN	EFI_NO_RESPONSE
+#define PLATFORM_ENETRESET	EFI_ABORTED
+#define PLATFORM_ENETUNREACH	EFI_NO_RESPONSE
+#define PLATFORM_ENFILE		EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENOBUFS	EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENODATA	EFI_NO_RESPONSE
+#define PLATFORM_ENODEV		EFI_DEVICE_ERROR
+#define PLATFORM_ENOENT		EFI_NOT_FOUND
+#define PLATFORM_ENOEXEC	EFI_LOAD_ERROR
+#define PLATFORM_ENOLCK		EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENOLINK	EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENOMEM		EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENOMSG		EFI_PROTOCOL_ERROR
+#define PLATFORM_ENOPROTOOPT	EFI_UNSUPPORTED
+#define PLATFORM_ENOSPC		EFI_VOLUME_FULL
+#define PLATFORM_ENOSR		EFI_OUT_OF_RESOURCES
+#define PLATFORM_ENOSTR		EFI_PROTOCOL_ERROR
+#define PLATFORM_ENOSYS		EFI_UNSUPPORTED
+#define PLATFORM_ENOTCONN	EFI_NOT_STARTED
+#define PLATFORM_ENOTDIR	EFI_VOLUME_CORRUPTED
+#define PLATFORM_ENOTEMPTY	EFI_VOLUME_CORRUPTED
+#define PLATFORM_ENOTSOCK	EFI_INVALID_PARAMETER
+#define PLATFORM_ENOTSUP	EFI_UNSUPPORTED
+#define PLATFORM_ENOTTY		EFI_UNSUPPORTED
+#define PLATFORM_ENXIO		EFI_NOT_FOUND
+#define PLATFORM_EOPNOTSUPP	EFI_UNSUPPORTED
+#define PLATFORM_EOVERFLOW	EFI_BUFFER_TOO_SMALL
+#define PLATFORM_EPERM		EFI_ACCESS_DENIED
+#define PLATFORM_EPIPE		EFI_ABORTED
+#define PLATFORM_EPROTO		EFI_PROTOCOL_ERROR
+#define PLATFORM_EPROTONOSUPPORT EFI_UNSUPPORTED
+#define PLATFORM_EPROTOTYPE	EFI_INVALID_PARAMETER
+#define PLATFORM_ERANGE		EFI_BUFFER_TOO_SMALL
+#define PLATFORM_EROFS		EFI_WRITE_PROTECTED
+#define PLATFORM_ESPIPE		EFI_END_OF_FILE
+#define PLATFORM_ESRCH		EFI_NOT_STARTED
+#define PLATFORM_ESTALE		EFI_PROTOCOL_ERROR
+#define PLATFORM_ETIME		EFI_TIMEOUT
+#define PLATFORM_ETIMEDOUT	EFI_TIMEOUT
+#define PLATFORM_ETXTBSY	EFI_MEDIA_CHANGED
+#define PLATFORM_EWOULDBLOCK	EFI_NOT_READY
+#define PLATFORM_EXDEV		EFI_VOLUME_CORRUPTED
+
+#endif /* _IPXE_ERRNO_EFI_H */
diff --git a/src/include/ipxe/errno/linux.h b/src/include/ipxe/errno/linux.h
new file mode 100644
index 000000000..11309b4ad
--- /dev/null
+++ b/src/include/ipxe/errno/linux.h
@@ -0,0 +1,113 @@
+#ifndef _IPXE_ERRNO_LINUX_H
+#define _IPXE_ERRNO_LINUX_H
+
+/**
+ * @file
+ *
+ * Linux platform error codes
+ *
+ * Linux error codes all fit inside 8 bits, so we just use them
+ * directly as our platform error codes.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/**
+ * Convert platform error code to platform component of iPXE error code
+ *
+ * @v platform		Platform error code
+ * @ret errno		Platform component of iPXE error code
+ */
+#define PLATFORM_TO_ERRNO( platform ) ( (platform) & 0xff )
+
+/**
+ * Convert iPXE error code to platform error code
+ *
+ * @v errno		iPXE error code
+ * @ret platform	Platform error code
+ */
+#define ERRNO_TO_PLATFORM( errno ) ( (errno) & 0xff )
+
+/* Platform-specific error codes */
+#define PLATFORM_ENOERR 0
+#define PLATFORM_E2BIG 7
+#define PLATFORM_EACCES 13
+#define PLATFORM_EADDRINUSE 98
+#define PLATFORM_EADDRNOTAVAIL 99
+#define PLATFORM_EAFNOSUPPORT 97
+#define PLATFORM_EAGAIN 11
+#define PLATFORM_EALREADY 114
+#define PLATFORM_EBADF 9
+#define PLATFORM_EBADMSG 74
+#define PLATFORM_EBUSY 16
+#define PLATFORM_ECANCELED 125
+#define PLATFORM_ECHILD 10
+#define PLATFORM_ECONNABORTED 103
+#define PLATFORM_ECONNREFUSED 111
+#define PLATFORM_ECONNRESET 104
+#define PLATFORM_EDEADLK 35
+#define PLATFORM_EDESTADDRREQ 89
+#define PLATFORM_EDOM 33
+#define PLATFORM_EDQUOT 122
+#define PLATFORM_EEXIST 17
+#define PLATFORM_EFAULT 14
+#define PLATFORM_EFBIG 27
+#define PLATFORM_EHOSTUNREACH 113
+#define PLATFORM_EIDRM 43
+#define PLATFORM_EILSEQ 84
+#define PLATFORM_EINPROGRESS 115
+#define PLATFORM_EINTR 4
+#define PLATFORM_EINVAL 22
+#define PLATFORM_EIO 5
+#define PLATFORM_EISCONN 106
+#define PLATFORM_EISDIR 21
+#define PLATFORM_ELOOP 40
+#define PLATFORM_EMFILE 24
+#define PLATFORM_EMLINK 31
+#define PLATFORM_EMSGSIZE 90
+#define PLATFORM_EMULTIHOP 72
+#define PLATFORM_ENAMETOOLONG 36
+#define PLATFORM_ENETDOWN 100
+#define PLATFORM_ENETRESET 102
+#define PLATFORM_ENETUNREACH 101
+#define PLATFORM_ENFILE 23
+#define PLATFORM_ENOBUFS 105
+#define PLATFORM_ENODATA 61
+#define PLATFORM_ENODEV 19
+#define PLATFORM_ENOENT 2
+#define PLATFORM_ENOEXEC 8
+#define PLATFORM_ENOLCK 37
+#define PLATFORM_ENOLINK 67
+#define PLATFORM_ENOMEM 12
+#define PLATFORM_ENOMSG 42
+#define PLATFORM_ENOPROTOOPT 92
+#define PLATFORM_ENOSPC 28
+#define PLATFORM_ENOSR 63
+#define PLATFORM_ENOSTR 60
+#define PLATFORM_ENOSYS 38
+#define PLATFORM_ENOTCONN 107
+#define PLATFORM_ENOTDIR 20
+#define PLATFORM_ENOTEMPTY 39
+#define PLATFORM_ENOTSOCK 88
+#define PLATFORM_ENOTSUP PLATFORM_EOPNOTSUPP
+#define PLATFORM_ENOTTY 25
+#define PLATFORM_ENXIO 6
+#define PLATFORM_EOPNOTSUPP 95
+#define PLATFORM_EOVERFLOW 75
+#define PLATFORM_EPERM 1
+#define PLATFORM_EPIPE 32
+#define PLATFORM_EPROTO 71
+#define PLATFORM_EPROTONOSUPPORT 93
+#define PLATFORM_EPROTOTYPE 91
+#define PLATFORM_ERANGE 34
+#define PLATFORM_EROFS 30
+#define PLATFORM_ESPIPE 29
+#define PLATFORM_ESRCH 3
+#define PLATFORM_ESTALE 116
+#define PLATFORM_ETIME 62
+#define PLATFORM_ETIMEDOUT 110
+#define PLATFORM_ETXTBSY 26
+#define PLATFORM_EWOULDBLOCK PLATFORM_EAGAIN
+#define PLATFORM_EXDEV 18
+
+#endif /* _IPXE_ERRNO_LINUX_H */