For pointer subtraction, the result is of type "ptrdiff_t". According to
the C11 standard (Committee Draft - April 12, 2011):
"When two pointers are subtracted, both shall point to elements of the
same array object, or one past the last element of the array object; the
result is the difference of the subscripts of the two array elements. The
size of the result is implementation-defined, and its type (a signed
integer type) is ptrdiff_t defined in the <stddef.h> header. If the result
is not representable in an object of that type, the behavior is
undefined."
In our codes, there are cases that the pointer subtraction is not
performed by pointers to elements of the same array object. This might
lead to potential issues, since the behavior is undefined according to C11
standard.
Also, since the size of type "ptrdiff_t" is implementation-defined. Some
static code checkers may warn that the pointer subtraction might underflow
first and then being cast to a bigger size. For example:
UINT8 *Ptr1, *Ptr2;
UINTN PtrDiff;
...
PtrDiff = (UINTN) (Ptr1 - Ptr2);
The commit will refine the pointer subtraction expressions by casting each
pointer to UINTN first and then perform the subtraction:
PtrDiff = (UINTN) Ptr1 - (UINTN) Ptr2;
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
The "success" messages in FtwRestart(), FtwAbort(), and FtwGetLastWrite()
should be logged on EFI_D_INFO level. We can also unify their format with
the __FUNCTION__ macro.
Cc: Star Zeng <star.zeng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Drew Jones <drjones@redhat.com>
Suggested-by: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18620 6f19259b-4bc3-4df7-8a09-765794883524
There may be anti-flash wear out feature to forbid erase operation after end of dxe.
The code is missing some error handling for erase operation failure,
it should return directly after the erase operation failed.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18320 6f19259b-4bc3-4df7-8a09-765794883524
1. Work space and spare block must be in a FVB with FV header.
Updated to work space and spare block could be in independent FVBs that are without FV header.
2. NV region, work space and spare block must have same BlockSize.
Updated to NV region, work space and spare block could have different BlockSize.
3. Works space size must be <= one block size.
Update to work space size could be <= one block size (not span blocks) or > one block size (block size aligned).
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16201 6f19259b-4bc3-4df7-8a09-765794883524
PEI variable implementation checks only the variable header signature for validity. This does not seem robust if system crash occurred during previous Reclaim() operation. If the crash occurred while FTW was rewriting the variable FV, the signature could be valid even though the rest of the FV isn't valid.
Solution: Add a FaultTolerantWritePei driver to check and provide the FTW last write status, then PEI variable and early phase(before FTW protocol ready) of DXE variable can check the status and determine if all or partial variable data has been backed up in spare block, and then use the backed up data.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14454 6f19259b-4bc3-4df7-8a09-765794883524
PcdFlashNvStorageFtwWorkingBase and PcdFlashNvStorageFtwSpareBase are
now updated each time an FVB instance is installed. This allows the
PCDs to be set at runtime at any time before the FVB is installed.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9312 6f19259b-4bc3-4df7-8a09-765794883524