MdePkg/UefiLib: don't special-case EFI_FILE_MODE_CREATE in OpenMode

While reviewing the patch that would land as 768b611136
("MdePkg/UefiLib: introduce EfiOpenFileByDevicePath()", 2018-08-16), Ray
pointed out that distinguishing EFI_FILE_MODE_CREATE was wasteful. Per
spec, if the file to create exists, then EFI_FILE_MODE_CREATE is ignored
by EFI_FILE_PROTOCOL.Open(), and the existent file is opened.

Therefore we don't need an attempt to "open-but-not-create" first, and a
fallback to "open-and-create-too" second -- that behavior is internal to
EFI_FILE_PROTOCOL.Open(). Remove the special-casing of
EFI_FILE_MODE_CREATE.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Suggested-by: Ruiyu Ni <ruiyu.ni@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1074
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
This commit is contained in:
Laszlo Ersek 2018-08-17 14:55:23 +02:00
parent e0c93c9b76
commit 5dbc768f1c
2 changed files with 9 additions and 50 deletions

View File

@ -1533,12 +1533,7 @@ EfiLocateProtocolBuffer (
On the remaining device path, the longest initial sequence of
FILEPATH_DEVICE_PATH nodes is node-wise traversed with
EFI_FILE_PROTOCOL.Open(). For the pathname fragment specified by each
traversed FILEPATH_DEVICE_PATH node, EfiOpenFileByDevicePath() first masks
EFI_FILE_MODE_CREATE out of OpenMode, and passes 0 for Attributes. If
EFI_FILE_PROTOCOL.Open() fails, and OpenMode includes EFI_FILE_MODE_CREATE,
then the operation is retried with the caller's OpenMode and Attributes
unmodified.
EFI_FILE_PROTOCOL.Open().
(As a consequence, if OpenMode includes EFI_FILE_MODE_CREATE, and Attributes
includes EFI_FILE_DIRECTORY, and each FILEPATH_DEVICE_PATH specifies a single
@ -1570,18 +1565,10 @@ EfiLocateProtocolBuffer (
the last node in FilePath.
@param[in] OpenMode The OpenMode parameter to pass to
EFI_FILE_PROTOCOL.Open(). For each
FILEPATH_DEVICE_PATH node in FilePath,
EfiOpenFileByDevicePath() first opens the specified
pathname fragment with EFI_FILE_MODE_CREATE masked
out of OpenMode and with Attributes set to 0, and
only retries the operation with EFI_FILE_MODE_CREATE
unmasked and Attributes propagated if the first open
attempt fails.
EFI_FILE_PROTOCOL.Open().
@param[in] Attributes The Attributes parameter to pass to
EFI_FILE_PROTOCOL.Open(), when EFI_FILE_MODE_CREATE
is propagated unmasked in OpenMode.
EFI_FILE_PROTOCOL.Open().
@retval EFI_SUCCESS The file or directory has been opened or
created.

View File

@ -1730,12 +1730,7 @@ EfiLocateProtocolBuffer (
On the remaining device path, the longest initial sequence of
FILEPATH_DEVICE_PATH nodes is node-wise traversed with
EFI_FILE_PROTOCOL.Open(). For the pathname fragment specified by each
traversed FILEPATH_DEVICE_PATH node, EfiOpenFileByDevicePath() first masks
EFI_FILE_MODE_CREATE out of OpenMode, and passes 0 for Attributes. If
EFI_FILE_PROTOCOL.Open() fails, and OpenMode includes EFI_FILE_MODE_CREATE,
then the operation is retried with the caller's OpenMode and Attributes
unmodified.
EFI_FILE_PROTOCOL.Open().
(As a consequence, if OpenMode includes EFI_FILE_MODE_CREATE, and Attributes
includes EFI_FILE_DIRECTORY, and each FILEPATH_DEVICE_PATH specifies a single
@ -1767,18 +1762,10 @@ EfiLocateProtocolBuffer (
the last node in FilePath.
@param[in] OpenMode The OpenMode parameter to pass to
EFI_FILE_PROTOCOL.Open(). For each
FILEPATH_DEVICE_PATH node in FilePath,
EfiOpenFileByDevicePath() first opens the specified
pathname fragment with EFI_FILE_MODE_CREATE masked
out of OpenMode and with Attributes set to 0, and
only retries the operation with EFI_FILE_MODE_CREATE
unmasked and Attributes propagated if the first open
attempt fails.
EFI_FILE_PROTOCOL.Open().
@param[in] Attributes The Attributes parameter to pass to
EFI_FILE_PROTOCOL.Open(), when EFI_FILE_MODE_CREATE
is propagated unmasked in OpenMode.
EFI_FILE_PROTOCOL.Open().
@retval EFI_SUCCESS The file or directory has been opened or
created.
@ -1889,31 +1876,16 @@ EfiOpenFileByDevicePath (
}
//
// Open the next pathname fragment with EFI_FILE_MODE_CREATE masked out and
// with Attributes set to 0.
// Open or create the file corresponding to the next pathname fragment.
//
Status = LastFile->Open (
LastFile,
&NextFile,
PathName,
OpenMode & ~(UINT64)EFI_FILE_MODE_CREATE,
0
OpenMode,
Attributes
);
//
// Retry with EFI_FILE_MODE_CREATE and the original Attributes if the first
// attempt failed, and the caller specified EFI_FILE_MODE_CREATE.
//
if (EFI_ERROR (Status) && (OpenMode & EFI_FILE_MODE_CREATE) != 0) {
Status = LastFile->Open (
LastFile,
&NextFile,
PathName,
OpenMode,
Attributes
);
}
//
// Release any AlignedPathName on both error and success paths; PathName is
// no longer needed.