BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275
The MemEncryptSevClearMmioPageEncMask() helper can be used for clearing
the memory encryption mask for the Mmio region.
The MemEncryptSevClearMmioPageEncMask() is a simplifies version of
MemEncryptSevClearPageEncMask() -- it does not flush the caches after
clearing the page encryption mask.
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
OvmfPkg/Include/Library/MemEncryptSevLib.h | 25 ++++++++++++++
.../BaseMemEncryptSevLib/X64/VirtualMemory.h | 23 +++++++++++++
.../Ia32/MemEncryptSevLib.c | 31 +++++++++++++++++
.../X64/MemEncryptSevLib.c | 33 +++++++++++++++++++
.../X64/PeiDxeVirtualMemory.c | 33 +++++++++++++++++++
5 files changed, 145 insertions(+)
diff --git a/OvmfPkg/Include/Library/MemEncryptSevLib.h b/OvmfPkg/Include/Library/MemEncryptSevLib.h
index 99f15a7d1271..b91490d5d44d 100644
--- a/OvmfPkg/Include/Library/MemEncryptSevLib.h
+++ b/OvmfPkg/Include/Library/MemEncryptSevLib.h
@@ -203,4 +203,29 @@ MemEncryptSevGetAddressRangeState (
IN UINTN Length
);
+/**
+ This function clears memory encryption bit for the MMIO region specified by
+ BaseAddress and NumPages.
+
+ @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
+ current CR3)
+ @param[in] BaseAddress The physical address that is the start
+ address of a MMIO region.
+ @param[in] NumPages The number of pages from start memory
+ region.
+
+ @retval RETURN_SUCCESS The attributes were cleared for the
+ memory region.
+ @retval RETURN_INVALID_PARAMETER Number of pages is zero.
+ @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
+ is not supported
+**/
+RETURN_STATUS
+EFIAPI
+MemEncryptSevClearMmioPageEncMask (
+ IN PHYSICAL_ADDRESS Cr3BaseAddress,
+ IN PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN NumPages
+ );
+
#endif // _MEM_ENCRYPT_SEV_LIB_H_
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
index fe2a0b2826cd..8dc39e647b90 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
@@ -126,4 +126,27 @@ InternalMemEncryptSevGetAddressRangeState (
IN UINTN Length
);
+/**
+ This function clears memory encryption bit for the MMIO region specified by
+ PhysicalAddress and Length.
+
+ @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
+ current CR3)
+ @param[in] PhysicalAddress The physical address that is the start
+ address of a MMIO region.
+ @param[in] Length The length of memory region
+
+ @retval RETURN_SUCCESS The attributes were cleared for the
+ memory region.
+ @retval RETURN_INVALID_PARAMETER Length is zero.
+ @retval RETURN_UNSUPPORTED Clearing the memory encyrption attribute
+ is not supported
+**/
+RETURN_STATUS
+EFIAPI
+InternalMemEncryptSevClearMmioPageEncMask (
+ IN PHYSICAL_ADDRESS Cr3BaseAddress,
+ IN PHYSICAL_ADDRESS PhysicalAddress,
+ IN UINTN Length
+ );
#endif
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
index 12a5bf495bd7..169d3118e44f 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
@@ -111,3 +111,34 @@ MemEncryptSevGetAddressRangeState (
//
return MemEncryptSevAddressRangeEncrypted;
}
+
+/**
+ This function clears memory encryption bit for the MMIO region specified by
+ BaseAddress and NumPages.
+
+ @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
+ current CR3)
+ @param[in] BaseAddress The physical address that is the start
+ address of a MMIO region.
+ @param[in] NumPages The number of pages from start memory
+ region.
+
+ @retval RETURN_SUCCESS The attributes were cleared for the
+ memory region.
+ @retval RETURN_INVALID_PARAMETER Number of pages is zero.
+ @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
+ is not supported
+**/
+RETURN_STATUS
+EFIAPI
+MemEncryptSevClearMmioPageEncMask (
+ IN PHYSICAL_ADDRESS Cr3BaseAddress,
+ IN PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN NumPages
+ )
+{
+ //
+ // Memory encryption bit is not accessible in 32-bit mode
+ //
+ return RETURN_UNSUPPORTED;
+}
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
index 4fea6a6be0ac..a2bf698bcde7 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
@@ -118,3 +118,36 @@ MemEncryptSevGetAddressRangeState (
Length
);
}
+
+/**
+ This function clears memory encryption bit for the mmio region specified by
+ BaseAddress and NumPages.
+
+ @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
+ current CR3)
+ @param[in] BaseAddress The physical address that is the start
+ address of a mmio region.
+ @param[in] NumPages The number of pages from start memory
+ region.
+
+ @retval RETURN_SUCCESS The attributes were cleared for the
+ memory region.
+ @retval RETURN_INVALID_PARAMETER Number of pages is zero.
+ @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
+ is not supported
+**/
+RETURN_STATUS
+EFIAPI
+MemEncryptSevClearMmioPageEncMask (
+ IN PHYSICAL_ADDRESS Cr3BaseAddress,
+ IN PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN NumPages
+ )
+{
+ return InternalMemEncryptSevClearMmioPageEncMask (
+ Cr3BaseAddress,
+ BaseAddress,
+ EFI_PAGES_TO_SIZE (NumPages)
+ );
+
+}
diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
index d3455e812bd1..a18d336a8789 100644
--- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
+++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
@@ -891,3 +891,36 @@ InternalMemEncryptSevSetMemoryEncrypted (
Flush
);
}
+
+/**
+ This function clears memory encryption bit for the MMIO region specified by
+ PhysicalAddress and Length.
+
+ @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
+ current CR3)
+ @param[in] PhysicalAddress The physical address that is the start
+ address of a MMIO region.
+ @param[in] Length The length of memory region
+
+ @retval RETURN_SUCCESS The attributes were cleared for the
+ memory region.
+ @retval RETURN_INVALID_PARAMETER Length is zero.
+ @retval RETURN_UNSUPPORTED Clearing the memory encyrption attribute
+ is not supported
+**/
+RETURN_STATUS
+EFIAPI
+InternalMemEncryptSevClearMmioPageEncMask (
+ IN PHYSICAL_ADDRESS Cr3BaseAddress,
+ IN PHYSICAL_ADDRESS PhysicalAddress,
+ IN UINTN Length
+ )
+{
+ return SetMemoryEncDec (
+ Cr3BaseAddress,
+ PhysicalAddress,
+ Length,
+ ClearCBit,
+ FALSE
+ );
+}
--
2.17.1
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On 05/07/21 22:38, Brijesh Singh wrote:
> BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275
>
> The MemEncryptSevClearMmioPageEncMask() helper can be used for clearing
> the memory encryption mask for the Mmio region.
>
> The MemEncryptSevClearMmioPageEncMask() is a simplifies version of
(1) s/simplifies/simplified/
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Thanks
Laszlo
> MemEncryptSevClearPageEncMask() -- it does not flush the caches after
> clearing the page encryption mask.
>
> Cc: James Bottomley <jejb@linux.ibm.com>
> Cc: Min Xu <min.m.xu@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Erdem Aktas <erdemaktas@google.com>
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
> OvmfPkg/Include/Library/MemEncryptSevLib.h | 25 ++++++++++++++
> .../BaseMemEncryptSevLib/X64/VirtualMemory.h | 23 +++++++++++++
> .../Ia32/MemEncryptSevLib.c | 31 +++++++++++++++++
> .../X64/MemEncryptSevLib.c | 33 +++++++++++++++++++
> .../X64/PeiDxeVirtualMemory.c | 33 +++++++++++++++++++
> 5 files changed, 145 insertions(+)
>
> diff --git a/OvmfPkg/Include/Library/MemEncryptSevLib.h b/OvmfPkg/Include/Library/MemEncryptSevLib.h
> index 99f15a7d1271..b91490d5d44d 100644
> --- a/OvmfPkg/Include/Library/MemEncryptSevLib.h
> +++ b/OvmfPkg/Include/Library/MemEncryptSevLib.h
> @@ -203,4 +203,29 @@ MemEncryptSevGetAddressRangeState (
> IN UINTN Length
> );
>
> +/**
> + This function clears memory encryption bit for the MMIO region specified by
> + BaseAddress and NumPages.
> +
> + @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
> + current CR3)
> + @param[in] BaseAddress The physical address that is the start
> + address of a MMIO region.
> + @param[in] NumPages The number of pages from start memory
> + region.
> +
> + @retval RETURN_SUCCESS The attributes were cleared for the
> + memory region.
> + @retval RETURN_INVALID_PARAMETER Number of pages is zero.
> + @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
> + is not supported
> +**/
> +RETURN_STATUS
> +EFIAPI
> +MemEncryptSevClearMmioPageEncMask (
> + IN PHYSICAL_ADDRESS Cr3BaseAddress,
> + IN PHYSICAL_ADDRESS BaseAddress,
> + IN UINTN NumPages
> + );
> +
> #endif // _MEM_ENCRYPT_SEV_LIB_H_
> diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
> index fe2a0b2826cd..8dc39e647b90 100644
> --- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
> +++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/VirtualMemory.h
> @@ -126,4 +126,27 @@ InternalMemEncryptSevGetAddressRangeState (
> IN UINTN Length
> );
>
> +/**
> + This function clears memory encryption bit for the MMIO region specified by
> + PhysicalAddress and Length.
> +
> + @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
> + current CR3)
> + @param[in] PhysicalAddress The physical address that is the start
> + address of a MMIO region.
> + @param[in] Length The length of memory region
> +
> + @retval RETURN_SUCCESS The attributes were cleared for the
> + memory region.
> + @retval RETURN_INVALID_PARAMETER Length is zero.
> + @retval RETURN_UNSUPPORTED Clearing the memory encyrption attribute
> + is not supported
> +**/
> +RETURN_STATUS
> +EFIAPI
> +InternalMemEncryptSevClearMmioPageEncMask (
> + IN PHYSICAL_ADDRESS Cr3BaseAddress,
> + IN PHYSICAL_ADDRESS PhysicalAddress,
> + IN UINTN Length
> + );
> #endif
> diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
> index 12a5bf495bd7..169d3118e44f 100644
> --- a/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
> +++ b/OvmfPkg/Library/BaseMemEncryptSevLib/Ia32/MemEncryptSevLib.c
> @@ -111,3 +111,34 @@ MemEncryptSevGetAddressRangeState (
> //
> return MemEncryptSevAddressRangeEncrypted;
> }
> +
> +/**
> + This function clears memory encryption bit for the MMIO region specified by
> + BaseAddress and NumPages.
> +
> + @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
> + current CR3)
> + @param[in] BaseAddress The physical address that is the start
> + address of a MMIO region.
> + @param[in] NumPages The number of pages from start memory
> + region.
> +
> + @retval RETURN_SUCCESS The attributes were cleared for the
> + memory region.
> + @retval RETURN_INVALID_PARAMETER Number of pages is zero.
> + @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
> + is not supported
> +**/
> +RETURN_STATUS
> +EFIAPI
> +MemEncryptSevClearMmioPageEncMask (
> + IN PHYSICAL_ADDRESS Cr3BaseAddress,
> + IN PHYSICAL_ADDRESS BaseAddress,
> + IN UINTN NumPages
> + )
> +{
> + //
> + // Memory encryption bit is not accessible in 32-bit mode
> + //
> + return RETURN_UNSUPPORTED;
> +}
> diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
> index 4fea6a6be0ac..a2bf698bcde7 100644
> --- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
> +++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c
> @@ -118,3 +118,36 @@ MemEncryptSevGetAddressRangeState (
> Length
> );
> }
> +
> +/**
> + This function clears memory encryption bit for the mmio region specified by
> + BaseAddress and NumPages.
> +
> + @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
> + current CR3)
> + @param[in] BaseAddress The physical address that is the start
> + address of a mmio region.
> + @param[in] NumPages The number of pages from start memory
> + region.
> +
> + @retval RETURN_SUCCESS The attributes were cleared for the
> + memory region.
> + @retval RETURN_INVALID_PARAMETER Number of pages is zero.
> + @retval RETURN_UNSUPPORTED Clearing the memory encryption attribute
> + is not supported
> +**/
> +RETURN_STATUS
> +EFIAPI
> +MemEncryptSevClearMmioPageEncMask (
> + IN PHYSICAL_ADDRESS Cr3BaseAddress,
> + IN PHYSICAL_ADDRESS BaseAddress,
> + IN UINTN NumPages
> + )
> +{
> + return InternalMemEncryptSevClearMmioPageEncMask (
> + Cr3BaseAddress,
> + BaseAddress,
> + EFI_PAGES_TO_SIZE (NumPages)
> + );
> +
> +}
> diff --git a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
> index d3455e812bd1..a18d336a8789 100644
> --- a/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
> +++ b/OvmfPkg/Library/BaseMemEncryptSevLib/X64/PeiDxeVirtualMemory.c
> @@ -891,3 +891,36 @@ InternalMemEncryptSevSetMemoryEncrypted (
> Flush
> );
> }
> +
> +/**
> + This function clears memory encryption bit for the MMIO region specified by
> + PhysicalAddress and Length.
> +
> + @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use
> + current CR3)
> + @param[in] PhysicalAddress The physical address that is the start
> + address of a MMIO region.
> + @param[in] Length The length of memory region
> +
> + @retval RETURN_SUCCESS The attributes were cleared for the
> + memory region.
> + @retval RETURN_INVALID_PARAMETER Length is zero.
> + @retval RETURN_UNSUPPORTED Clearing the memory encyrption attribute
> + is not supported
> +**/
> +RETURN_STATUS
> +EFIAPI
> +InternalMemEncryptSevClearMmioPageEncMask (
> + IN PHYSICAL_ADDRESS Cr3BaseAddress,
> + IN PHYSICAL_ADDRESS PhysicalAddress,
> + IN UINTN Length
> + )
> +{
> + return SetMemoryEncDec (
> + Cr3BaseAddress,
> + PhysicalAddress,
> + Length,
> + ClearCBit,
> + FALSE
> + );
> +}
>
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