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From: Leif Lindholm <leif.lindholm@linaro.org>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: edk2-devel@lists.01.org, lersek@redhat.com
Subject: Re: [PATCH 2/5] ArmPkg: move ARM version of SetMemoryAttributes to ArmMmuLib
Date: Mon, 6 Mar 2017 16:03:25 +0000	[thread overview]
Message-ID: <20170306160325.GX16034@bivouac.eciton.net> (raw)
In-Reply-To: <1488385903-30267-3-git-send-email-ard.biesheuvel@linaro.org>

n Wed, Mar 01, 2017 at 04:31:40PM +0000, Ard Biesheuvel wrote:
> ... where it belongs, since AARCH64 already keeps it there, and
> non DXE users of ArmMmuLib (such as DxeIpl, for the non-executable
> stack) may need its functionality as well.
> 
> While at it, rename SetMemoryAttributes to ArmSetMemoryAttributes,
> and make any functions that are not exported STATIC. Also, replace
> an explicit gBS->AllocatePages() call [which is DXE specific] with
> MemoryAllocationLib::AllocatePages().
> 
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  ArmPkg/Drivers/CpuDxe/Arm/Mmu.c                  | 368 --------------------
>  ArmPkg/Drivers/CpuDxe/CpuDxe.h                   |  14 +-
>  ArmPkg/Drivers/CpuDxe/CpuMmuCommon.c             |   2 +-
>  ArmPkg/Include/Library/ArmMmuLib.h               |   8 +
>  ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibCore.c |   2 +-
>  ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c     | 368 ++++++++++++++++++++
>  6 files changed, 379 insertions(+), 383 deletions(-)
> 
> diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c
> index 6322d301060e..b985dd743f02 100644
> --- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c
> +++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c
> @@ -343,374 +343,6 @@ SyncCacheConfig (
>    return EFI_SUCCESS;
>  }
>  
> -
> -
> -EFI_STATUS
> -UpdatePageEntries (
> -  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> -  IN UINT64                    Length,
> -  IN UINT64                    Attributes,
> -  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> -  )
> -{
> -  EFI_STATUS    Status;
> -  UINT32        EntryValue;
> -  UINT32        EntryMask;
> -  UINT32        FirstLevelIdx;
> -  UINT32        Offset;
> -  UINT32        NumPageEntries;
> -  UINT32        Descriptor;
> -  UINT32        p;
> -  UINT32        PageTableIndex;
> -  UINT32        PageTableEntry;
> -  UINT32        CurrentPageTableEntry;
> -  VOID          *Mva;
> -
> -  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> -  volatile ARM_PAGE_TABLE_ENTRY         *PageTable;
> -
> -  Status = EFI_SUCCESS;
> -
> -  // EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
> -  // EntryValue: values at bit positions specified by EntryMask
> -  EntryMask = TT_DESCRIPTOR_PAGE_TYPE_MASK | TT_DESCRIPTOR_PAGE_AP_MASK;
> -  if ((Attributes & EFI_MEMORY_XP) != 0) {
> -    EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE_XN;
> -  } else {
> -    EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE;
> -  }
> -
> -  // Although the PI spec is unclear on this the GCD guarantees that only
> -  // one Attribute bit is set at a time, so we can safely use a switch statement
> -  if ((Attributes & EFI_MEMORY_UC) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> -    // map to strongly ordered
> -    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
> -  } else if ((Attributes & EFI_MEMORY_WC) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> -    // map to normal non-cachable
> -    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
> -  } else if ((Attributes & EFI_MEMORY_WT) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> -    // write through with no-allocate
> -    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
> -  } else if ((Attributes & EFI_MEMORY_WB) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> -    // write back (with allocate)
> -    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
> -  }
> -
> -  if ((Attributes & EFI_MEMORY_RO) != 0) {
> -    EntryValue |= TT_DESCRIPTOR_PAGE_AP_RO_RO;
> -  } else {
> -    EntryValue |= TT_DESCRIPTOR_PAGE_AP_RW_RW;
> -  }
> -
> -  // Obtain page table base
> -  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> -
> -  // Calculate number of 4KB page table entries to change
> -  NumPageEntries = Length / TT_DESCRIPTOR_PAGE_SIZE;
> -
> -  // Iterate for the number of 4KB pages to change
> -  Offset = 0;
> -  for(p = 0; p < NumPageEntries; p++) {
> -    // Calculate index into first level translation table for page table value
> -
> -    FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress + Offset) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> -    ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> -
> -    // Read the descriptor from the first level page table
> -    Descriptor = FirstLevelTable[FirstLevelIdx];
> -
> -    // Does this descriptor need to be converted from section entry to 4K pages?
> -    if (!TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(Descriptor)) {
> -      Status = ConvertSectionToPages (FirstLevelIdx << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
> -      if (EFI_ERROR(Status)) {
> -        // Exit for loop
> -        break;
> -      }
> -
> -      // Re-read descriptor
> -      Descriptor = FirstLevelTable[FirstLevelIdx];
> -    }
> -
> -    // Obtain page table base address
> -    PageTable = (ARM_PAGE_TABLE_ENTRY *)TT_DESCRIPTOR_PAGE_BASE_ADDRESS(Descriptor);
> -
> -    // Calculate index into the page table
> -    PageTableIndex = ((BaseAddress + Offset) & TT_DESCRIPTOR_PAGE_INDEX_MASK) >> TT_DESCRIPTOR_PAGE_BASE_SHIFT;
> -    ASSERT (PageTableIndex < TRANSLATION_TABLE_PAGE_COUNT);
> -
> -    // Get the entry
> -    CurrentPageTableEntry = PageTable[PageTableIndex];
> -
> -    // Mask off appropriate fields
> -    PageTableEntry = CurrentPageTableEntry & ~EntryMask;
> -
> -    // Mask in new attributes and/or permissions
> -    PageTableEntry |= EntryValue;
> -
> -    if (VirtualMask != 0) {
> -      // Make this virtual address point at a physical page
> -      PageTableEntry &= ~VirtualMask;
> -    }
> -
> -    if (CurrentPageTableEntry  != PageTableEntry) {
> -      Mva = (VOID *)(UINTN)((((UINTN)FirstLevelIdx) << TT_DESCRIPTOR_SECTION_BASE_SHIFT) + (PageTableIndex << TT_DESCRIPTOR_PAGE_BASE_SHIFT));
> -      if ((CurrentPageTableEntry & TT_DESCRIPTOR_PAGE_CACHEABLE_MASK) == TT_DESCRIPTOR_PAGE_CACHEABLE_MASK) {
> -        // The current section mapping is cacheable so Clean/Invalidate the MVA of the page
> -        // Note assumes switch(Attributes), not ARMv7 possibilities
> -        WriteBackInvalidateDataCacheRange (Mva, TT_DESCRIPTOR_PAGE_SIZE);
> -      }
> -
> -      // Only need to update if we are changing the entry
> -      PageTable[PageTableIndex] = PageTableEntry;
> -      ArmUpdateTranslationTableEntry ((VOID *)&PageTable[PageTableIndex], Mva);
> -    }
> -
> -    Status = EFI_SUCCESS;
> -    Offset += TT_DESCRIPTOR_PAGE_SIZE;
> -
> -  } // End first level translation table loop
> -
> -  return Status;
> -}
> -
> -
> -
> -EFI_STATUS
> -UpdateSectionEntries (
> -  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> -  IN UINT64                    Length,
> -  IN UINT64                    Attributes,
> -  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> -  )
> -{
> -  EFI_STATUS    Status = EFI_SUCCESS;
> -  UINT32        EntryMask;
> -  UINT32        EntryValue;
> -  UINT32        FirstLevelIdx;
> -  UINT32        NumSections;
> -  UINT32        i;
> -  UINT32        CurrentDescriptor;
> -  UINT32        Descriptor;
> -  VOID          *Mva;
> -  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> -
> -  // EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
> -  // EntryValue: values at bit positions specified by EntryMask
> -
> -  // Make sure we handle a section range that is unmapped
> -  EntryMask = TT_DESCRIPTOR_SECTION_TYPE_MASK | TT_DESCRIPTOR_SECTION_XN_MASK |
> -              TT_DESCRIPTOR_SECTION_AP_MASK;
> -  EntryValue = TT_DESCRIPTOR_SECTION_TYPE_SECTION;
> -
> -  // Although the PI spec is unclear on this the GCD guarantees that only
> -  // one Attribute bit is set at a time, so we can safely use a switch statement
> -  if ((Attributes & EFI_MEMORY_UC) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> -    // map to strongly ordered
> -    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
> -  } else if ((Attributes & EFI_MEMORY_WC) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> -    // map to normal non-cachable
> -    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
> -  } else if ((Attributes & EFI_MEMORY_WT) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> -    // write through with no-allocate
> -    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
> -  } else if ((Attributes & EFI_MEMORY_WB) != 0) {
> -    // modify cacheability attributes
> -    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> -    // write back (with allocate)
> -    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
> -  }
> -
> -  if ((Attributes & EFI_MEMORY_RO) != 0) {
> -    EntryValue |= TT_DESCRIPTOR_SECTION_AP_RO_RO;
> -  } else {
> -    EntryValue |= TT_DESCRIPTOR_SECTION_AP_RW_RW;
> -  }
> -
> -  if ((Attributes & EFI_MEMORY_XP) != 0) {
> -    EntryValue |= TT_DESCRIPTOR_SECTION_XN_MASK;
> -  }
> -
> -  // obtain page table base
> -  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> -
> -  // calculate index into first level translation table for start of modification
> -  FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> -  ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> -
> -  // calculate number of 1MB first level entries this applies to
> -  NumSections = Length / TT_DESCRIPTOR_SECTION_SIZE;
> -
> -  // iterate through each descriptor
> -  for(i=0; i<NumSections; i++) {
> -    CurrentDescriptor = FirstLevelTable[FirstLevelIdx + i];
> -
> -    // has this descriptor already been coverted to pages?
> -    if (TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(CurrentDescriptor)) {
> -      // forward this 1MB range to page table function instead
> -      Status = UpdatePageEntries ((FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT, TT_DESCRIPTOR_SECTION_SIZE, Attributes, VirtualMask);
> -    } else {
> -      // still a section entry
> -
> -      // mask off appropriate fields
> -      Descriptor = CurrentDescriptor & ~EntryMask;
> -
> -      // mask in new attributes and/or permissions
> -      Descriptor |= EntryValue;
> -      if (VirtualMask != 0) {
> -        Descriptor &= ~VirtualMask;
> -      }
> -
> -      if (CurrentDescriptor  != Descriptor) {
> -        Mva = (VOID *)(UINTN)(((UINTN)FirstLevelTable) << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
> -        if ((CurrentDescriptor & TT_DESCRIPTOR_SECTION_CACHEABLE_MASK) == TT_DESCRIPTOR_SECTION_CACHEABLE_MASK) {
> -          // The current section mapping is cacheable so Clean/Invalidate the MVA of the section
> -          // Note assumes switch(Attributes), not ARMv7 possabilities
> -          WriteBackInvalidateDataCacheRange (Mva, SIZE_1MB);
> -        }
> -
> -        // Only need to update if we are changing the descriptor
> -        FirstLevelTable[FirstLevelIdx + i] = Descriptor;
> -        ArmUpdateTranslationTableEntry ((VOID *)&FirstLevelTable[FirstLevelIdx + i], Mva);
> -      }
> -
> -      Status = EFI_SUCCESS;
> -    }
> -  }
> -
> -  return Status;
> -}
> -
> -EFI_STATUS
> -ConvertSectionToPages (
> -  IN EFI_PHYSICAL_ADDRESS  BaseAddress
> -  )
> -{
> -  EFI_STATUS              Status;
> -  EFI_PHYSICAL_ADDRESS    PageTableAddr;
> -  UINT32                  FirstLevelIdx;
> -  UINT32                  SectionDescriptor;
> -  UINT32                  PageTableDescriptor;
> -  UINT32                  PageDescriptor;
> -  UINT32                  Index;
> -
> -  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> -  volatile ARM_PAGE_TABLE_ENTRY         *PageTable;
> -
> -  DEBUG ((EFI_D_PAGE, "Converting section at 0x%x to pages\n", (UINTN)BaseAddress));
> -
> -  // Obtain page table base
> -  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> -
> -  // Calculate index into first level translation table for start of modification
> -  FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> -  ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> -
> -  // Get section attributes and convert to page attributes
> -  SectionDescriptor = FirstLevelTable[FirstLevelIdx];
> -  PageDescriptor = TT_DESCRIPTOR_PAGE_TYPE_PAGE | ConvertSectionAttributesToPageAttributes (SectionDescriptor, FALSE);
> -
> -  // Allocate a page table for the 4KB entries (we use up a full page even though we only need 1KB)
> -  Status = gBS->AllocatePages (AllocateAnyPages, EfiBootServicesData, 1, &PageTableAddr);
> -  if (EFI_ERROR(Status)) {
> -    return Status;
> -  }
> -
> -  PageTable = (volatile ARM_PAGE_TABLE_ENTRY *)(UINTN)PageTableAddr;
> -
> -  // Write the page table entries out
> -  for (Index = 0; Index < TRANSLATION_TABLE_PAGE_COUNT; Index++) {
> -    PageTable[Index] = TT_DESCRIPTOR_PAGE_BASE_ADDRESS(BaseAddress + (Index << 12)) | PageDescriptor;
> -  }
> -
> -  // Flush d-cache so descriptors make it back to uncached memory for subsequent table walks
> -  WriteBackInvalidateDataCacheRange ((VOID *)(UINTN)PageTableAddr, TT_DESCRIPTOR_PAGE_SIZE);
> -
> -  // Formulate page table entry, Domain=0, NS=0
> -  PageTableDescriptor = (((UINTN)PageTableAddr) & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK) | TT_DESCRIPTOR_SECTION_TYPE_PAGE_TABLE;
> -
> -  // Write the page table entry out, replacing section entry
> -  FirstLevelTable[FirstLevelIdx] = PageTableDescriptor;
> -
> -  return EFI_SUCCESS;
> -}
> -
> -
> -
> -EFI_STATUS
> -SetMemoryAttributes (
> -  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> -  IN UINT64                    Length,
> -  IN UINT64                    Attributes,
> -  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> -  )
> -{
> -  EFI_STATUS    Status;
> -  UINT64        ChunkLength;
> -  BOOLEAN       FlushTlbs;
> -
> -  FlushTlbs = FALSE;
> -  while (Length > 0) {
> -    if ((BaseAddress % TT_DESCRIPTOR_SECTION_SIZE == 0) &&
> -        Length >= TT_DESCRIPTOR_SECTION_SIZE) {
> -
> -      ChunkLength = Length - Length % TT_DESCRIPTOR_SECTION_SIZE;
> -
> -      DEBUG ((DEBUG_PAGE | DEBUG_INFO,
> -        "SetMemoryAttributes(): MMU section 0x%lx length 0x%lx to %lx\n",
> -        BaseAddress, ChunkLength, Attributes));
> -
> -      Status = UpdateSectionEntries (BaseAddress, ChunkLength, Attributes,
> -                 VirtualMask);
> -
> -      FlushTlbs = TRUE;
> -    } else {
> -
> -      //
> -      // Process page by page until the next section boundary, but only if
> -      // we have more than a section's worth of area to deal with after that.
> -      //
> -      ChunkLength = TT_DESCRIPTOR_SECTION_SIZE -
> -                    (BaseAddress % TT_DESCRIPTOR_SECTION_SIZE);
> -      if (ChunkLength + TT_DESCRIPTOR_SECTION_SIZE > Length) {
> -        ChunkLength = Length;
> -      }
> -
> -      DEBUG ((DEBUG_PAGE | DEBUG_INFO,
> -        "SetMemoryAttributes(): MMU page 0x%lx length 0x%lx to %lx\n",
> -        BaseAddress, ChunkLength, Attributes));
> -
> -      Status = UpdatePageEntries (BaseAddress, ChunkLength, Attributes,
> -                 VirtualMask);
> -    }
> -
> -    if (EFI_ERROR (Status)) {
> -      break;
> -    }
> -
> -    BaseAddress += ChunkLength;
> -    Length -= ChunkLength;
> -  }
> -
> -  if (FlushTlbs) {
> -    ArmInvalidateTlb ();
> -  }
> -  return Status;
> -}
> -
>  UINT64
>  EfiAttributeToArmAttribute (
>    IN UINT64                    EfiAttributes
> diff --git a/ArmPkg/Drivers/CpuDxe/CpuDxe.h b/ArmPkg/Drivers/CpuDxe/CpuDxe.h
> index a46db8d25754..a0f71e69ec09 100644
> --- a/ArmPkg/Drivers/CpuDxe/CpuDxe.h
> +++ b/ArmPkg/Drivers/CpuDxe/CpuDxe.h
> @@ -19,6 +19,7 @@
>  #include <Uefi.h>
>  
>  #include <Library/ArmLib.h>
> +#include <Library/ArmMmuLib.h>
>  #include <Library/BaseMemoryLib.h>
>  #include <Library/DebugLib.h>
>  #include <Library/PcdLib.h>
> @@ -112,11 +113,6 @@ SyncCacheConfig (
>    IN  EFI_CPU_ARCH_PROTOCOL *CpuProtocol
>    );
>  
> -EFI_STATUS
> -ConvertSectionToPages (
> -  IN EFI_PHYSICAL_ADDRESS  BaseAddress
> -  );
> -
>  /**
>   * Publish ARM Processor Data table in UEFI SYSTEM Table.
>   * @param  HobStart               Pointer to the beginning of the HOB List from PEI.
> @@ -132,14 +128,6 @@ PublishArmProcessorTable(
>    VOID
>    );
>  
> -EFI_STATUS
> -SetMemoryAttributes (
> -  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> -  IN UINT64                    Length,
> -  IN UINT64                    Attributes,
> -  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> -  );
> -
>  // The ARM Attributes might be defined on 64-bit (case of the long format description table)
>  UINT64
>  EfiAttributeToArmAttribute (
> diff --git a/ArmPkg/Drivers/CpuDxe/CpuMmuCommon.c b/ArmPkg/Drivers/CpuDxe/CpuMmuCommon.c
> index 0f36a058407a..d0a3fedd3aa7 100644
> --- a/ArmPkg/Drivers/CpuDxe/CpuMmuCommon.c
> +++ b/ArmPkg/Drivers/CpuDxe/CpuMmuCommon.c
> @@ -210,7 +210,7 @@ CpuSetMemoryAttributes (
>    if (EFI_ERROR (Status) || (RegionArmAttributes != ArmAttributes) ||
>        ((BaseAddress + Length) > (RegionBaseAddress + RegionLength)))
>    {
> -    return SetMemoryAttributes (BaseAddress, Length, EfiAttributes, 0);
> +    return ArmSetMemoryAttributes (BaseAddress, Length, EfiAttributes, 0);
>    } else {
>      return EFI_SUCCESS;
>    }
> diff --git a/ArmPkg/Include/Library/ArmMmuLib.h b/ArmPkg/Include/Library/ArmMmuLib.h
> index c1d43872d548..d3a302fa8125 100644
> --- a/ArmPkg/Include/Library/ArmMmuLib.h
> +++ b/ArmPkg/Include/Library/ArmMmuLib.h
> @@ -62,4 +62,12 @@ ArmReplaceLiveTranslationEntry (
>    IN  UINT64  Value
>    );
>  
> +EFI_STATUS
> +ArmSetMemoryAttributes (
> +  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> +  IN UINT64                    Length,
> +  IN UINT64                    Attributes,
> +  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> +  );
> +
>  #endif
> diff --git a/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibCore.c b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibCore.c
> index df170d20a2c2..77f108971f3e 100644
> --- a/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibCore.c
> +++ b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibCore.c
> @@ -447,7 +447,7 @@ GcdAttributeToPageAttribute (
>  }
>  
>  EFI_STATUS
> -SetMemoryAttributes (
> +ArmSetMemoryAttributes (
>    IN EFI_PHYSICAL_ADDRESS      BaseAddress,
>    IN UINT64                    Length,
>    IN UINT64                    Attributes,
> diff --git a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
> index 4b6f4ce392b7..93980d6d12db 100644
> --- a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
> +++ b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
> @@ -16,6 +16,7 @@
>  #include <Uefi.h>
>  #include <Chipset/ArmV7.h>
>  #include <Library/BaseMemoryLib.h>
> +#include <Library/CacheMaintenanceLib.h>
>  #include <Library/MemoryAllocationLib.h>
>  #include <Library/ArmLib.h>
>  #include <Library/BaseLib.h>
> @@ -36,6 +37,12 @@
>  #define ID_MMFR0_SHR_IMP_HW_COHERENT   1
>  #define ID_MMFR0_SHR_IGNORED         0xf
>  
> +// First Level Descriptors
> +typedef UINT32    ARM_FIRST_LEVEL_DESCRIPTOR;
> +
> +// Second Level Descriptors
> +typedef UINT32    ARM_PAGE_TABLE_ENTRY;
> +

Copied from ArmPkg/Drivers/CpuDxe/Arm/Mmu.c, but not deleted there.
Can it be, or can it be moved out into a header somewhere?

No other comments.

/
    Leif

>  UINTN
>  EFIAPI
>  ArmReadIdMmfr0 (
> @@ -406,6 +413,367 @@ ArmConfigureMmu (
>    return RETURN_SUCCESS;
>  }
>  
> +STATIC
> +EFI_STATUS
> +ConvertSectionToPages (
> +  IN EFI_PHYSICAL_ADDRESS  BaseAddress
> +  )
> +{
> +  UINT32                  FirstLevelIdx;
> +  UINT32                  SectionDescriptor;
> +  UINT32                  PageTableDescriptor;
> +  UINT32                  PageDescriptor;
> +  UINT32                  Index;
> +
> +  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> +  volatile ARM_PAGE_TABLE_ENTRY         *PageTable;
> +
> +  DEBUG ((EFI_D_PAGE, "Converting section at 0x%x to pages\n", (UINTN)BaseAddress));
> +
> +  // Obtain page table base
> +  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> +
> +  // Calculate index into first level translation table for start of modification
> +  FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> +  ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> +
> +  // Get section attributes and convert to page attributes
> +  SectionDescriptor = FirstLevelTable[FirstLevelIdx];
> +  PageDescriptor = TT_DESCRIPTOR_PAGE_TYPE_PAGE | ConvertSectionAttributesToPageAttributes (SectionDescriptor, FALSE);
> +
> +  // Allocate a page table for the 4KB entries (we use up a full page even though we only need 1KB)
> +  PageTable = (volatile ARM_PAGE_TABLE_ENTRY *)AllocatePages (1);
> +  if (PageTable == NULL) {
> +    return EFI_OUT_OF_RESOURCES;
> +  }
> +
> +  // Write the page table entries out
> +  for (Index = 0; Index < TRANSLATION_TABLE_PAGE_COUNT; Index++) {
> +    PageTable[Index] = TT_DESCRIPTOR_PAGE_BASE_ADDRESS(BaseAddress + (Index << 12)) | PageDescriptor;
> +  }
> +
> +  // Flush d-cache so descriptors make it back to uncached memory for subsequent table walks
> +  WriteBackInvalidateDataCacheRange ((VOID *)PageTable, TT_DESCRIPTOR_PAGE_SIZE);
> +
> +  // Formulate page table entry, Domain=0, NS=0
> +  PageTableDescriptor = (((UINTN)PageTable) & TT_DESCRIPTOR_SECTION_PAGETABLE_ADDRESS_MASK) | TT_DESCRIPTOR_SECTION_TYPE_PAGE_TABLE;
> +
> +  // Write the page table entry out, replacing section entry
> +  FirstLevelTable[FirstLevelIdx] = PageTableDescriptor;
> +
> +  return EFI_SUCCESS;
> +}
> +
> +STATIC
> +EFI_STATUS
> +UpdatePageEntries (
> +  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> +  IN UINT64                    Length,
> +  IN UINT64                    Attributes,
> +  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> +  )
> +{
> +  EFI_STATUS    Status;
> +  UINT32        EntryValue;
> +  UINT32        EntryMask;
> +  UINT32        FirstLevelIdx;
> +  UINT32        Offset;
> +  UINT32        NumPageEntries;
> +  UINT32        Descriptor;
> +  UINT32        p;
> +  UINT32        PageTableIndex;
> +  UINT32        PageTableEntry;
> +  UINT32        CurrentPageTableEntry;
> +  VOID          *Mva;
> +
> +  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> +  volatile ARM_PAGE_TABLE_ENTRY         *PageTable;
> +
> +  Status = EFI_SUCCESS;
> +
> +  // EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
> +  // EntryValue: values at bit positions specified by EntryMask
> +  EntryMask = TT_DESCRIPTOR_PAGE_TYPE_MASK | TT_DESCRIPTOR_PAGE_AP_MASK;
> +  if ((Attributes & EFI_MEMORY_XP) != 0) {
> +    EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE_XN;
> +  } else {
> +    EntryValue = TT_DESCRIPTOR_PAGE_TYPE_PAGE;
> +  }
> +
> +  // Although the PI spec is unclear on this the GCD guarantees that only
> +  // one Attribute bit is set at a time, so we can safely use a switch statement
> +  if ((Attributes & EFI_MEMORY_UC) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> +    // map to strongly ordered
> +    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
> +  } else if ((Attributes & EFI_MEMORY_WC) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> +    // map to normal non-cachable
> +    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
> +  } else if ((Attributes & EFI_MEMORY_WT) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> +    // write through with no-allocate
> +    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
> +  } else if ((Attributes & EFI_MEMORY_WB) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_MASK;
> +    // write back (with allocate)
> +    EntryValue |= TT_DESCRIPTOR_PAGE_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
> +  }
> +
> +  if ((Attributes & EFI_MEMORY_RO) != 0) {
> +    EntryValue |= TT_DESCRIPTOR_PAGE_AP_RO_RO;
> +  } else {
> +    EntryValue |= TT_DESCRIPTOR_PAGE_AP_RW_RW;
> +  }
> +
> +  // Obtain page table base
> +  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> +
> +  // Calculate number of 4KB page table entries to change
> +  NumPageEntries = Length / TT_DESCRIPTOR_PAGE_SIZE;
> +
> +  // Iterate for the number of 4KB pages to change
> +  Offset = 0;
> +  for(p = 0; p < NumPageEntries; p++) {
> +    // Calculate index into first level translation table for page table value
> +
> +    FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress + Offset) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> +    ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> +
> +    // Read the descriptor from the first level page table
> +    Descriptor = FirstLevelTable[FirstLevelIdx];
> +
> +    // Does this descriptor need to be converted from section entry to 4K pages?
> +    if (!TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(Descriptor)) {
> +      Status = ConvertSectionToPages (FirstLevelIdx << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
> +      if (EFI_ERROR(Status)) {
> +        // Exit for loop
> +        break;
> +      }
> +
> +      // Re-read descriptor
> +      Descriptor = FirstLevelTable[FirstLevelIdx];
> +    }
> +
> +    // Obtain page table base address
> +    PageTable = (ARM_PAGE_TABLE_ENTRY *)TT_DESCRIPTOR_PAGE_BASE_ADDRESS(Descriptor);
> +
> +    // Calculate index into the page table
> +    PageTableIndex = ((BaseAddress + Offset) & TT_DESCRIPTOR_PAGE_INDEX_MASK) >> TT_DESCRIPTOR_PAGE_BASE_SHIFT;
> +    ASSERT (PageTableIndex < TRANSLATION_TABLE_PAGE_COUNT);
> +
> +    // Get the entry
> +    CurrentPageTableEntry = PageTable[PageTableIndex];
> +
> +    // Mask off appropriate fields
> +    PageTableEntry = CurrentPageTableEntry & ~EntryMask;
> +
> +    // Mask in new attributes and/or permissions
> +    PageTableEntry |= EntryValue;
> +
> +    if (VirtualMask != 0) {
> +      // Make this virtual address point at a physical page
> +      PageTableEntry &= ~VirtualMask;
> +    }
> +
> +    if (CurrentPageTableEntry  != PageTableEntry) {
> +      Mva = (VOID *)(UINTN)((((UINTN)FirstLevelIdx) << TT_DESCRIPTOR_SECTION_BASE_SHIFT) + (PageTableIndex << TT_DESCRIPTOR_PAGE_BASE_SHIFT));
> +      if ((CurrentPageTableEntry & TT_DESCRIPTOR_PAGE_CACHEABLE_MASK) == TT_DESCRIPTOR_PAGE_CACHEABLE_MASK) {
> +        // The current section mapping is cacheable so Clean/Invalidate the MVA of the page
> +        // Note assumes switch(Attributes), not ARMv7 possibilities
> +        WriteBackInvalidateDataCacheRange (Mva, TT_DESCRIPTOR_PAGE_SIZE);
> +      }
> +
> +      // Only need to update if we are changing the entry
> +      PageTable[PageTableIndex] = PageTableEntry;
> +      ArmUpdateTranslationTableEntry ((VOID *)&PageTable[PageTableIndex], Mva);
> +    }
> +
> +    Status = EFI_SUCCESS;
> +    Offset += TT_DESCRIPTOR_PAGE_SIZE;
> +
> +  } // End first level translation table loop
> +
> +  return Status;
> +}
> +
> +STATIC
> +EFI_STATUS
> +UpdateSectionEntries (
> +  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> +  IN UINT64                    Length,
> +  IN UINT64                    Attributes,
> +  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> +  )
> +{
> +  EFI_STATUS    Status = EFI_SUCCESS;
> +  UINT32        EntryMask;
> +  UINT32        EntryValue;
> +  UINT32        FirstLevelIdx;
> +  UINT32        NumSections;
> +  UINT32        i;
> +  UINT32        CurrentDescriptor;
> +  UINT32        Descriptor;
> +  VOID          *Mva;
> +  volatile ARM_FIRST_LEVEL_DESCRIPTOR   *FirstLevelTable;
> +
> +  // EntryMask: bitmask of values to change (1 = change this value, 0 = leave alone)
> +  // EntryValue: values at bit positions specified by EntryMask
> +
> +  // Make sure we handle a section range that is unmapped
> +  EntryMask = TT_DESCRIPTOR_SECTION_TYPE_MASK | TT_DESCRIPTOR_SECTION_XN_MASK |
> +              TT_DESCRIPTOR_SECTION_AP_MASK;
> +  EntryValue = TT_DESCRIPTOR_SECTION_TYPE_SECTION;
> +
> +  // Although the PI spec is unclear on this the GCD guarantees that only
> +  // one Attribute bit is set at a time, so we can safely use a switch statement
> +  if ((Attributes & EFI_MEMORY_UC) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> +    // map to strongly ordered
> +    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_STRONGLY_ORDERED; // TEX[2:0] = 0, C=0, B=0
> +  } else if ((Attributes & EFI_MEMORY_WC) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> +    // map to normal non-cachable
> +    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_NON_CACHEABLE; // TEX [2:0]= 001 = 0x2, B=0, C=0
> +  } else if ((Attributes & EFI_MEMORY_WT) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> +    // write through with no-allocate
> +    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_THROUGH_NO_ALLOC; // TEX [2:0] = 0, C=1, B=0
> +  } else if ((Attributes & EFI_MEMORY_WB) != 0) {
> +    // modify cacheability attributes
> +    EntryMask |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_MASK;
> +    // write back (with allocate)
> +    EntryValue |= TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC; // TEX [2:0] = 001, C=1, B=1
> +  }
> +
> +  if ((Attributes & EFI_MEMORY_RO) != 0) {
> +    EntryValue |= TT_DESCRIPTOR_SECTION_AP_RO_RO;
> +  } else {
> +    EntryValue |= TT_DESCRIPTOR_SECTION_AP_RW_RW;
> +  }
> +
> +  if ((Attributes & EFI_MEMORY_XP) != 0) {
> +    EntryValue |= TT_DESCRIPTOR_SECTION_XN_MASK;
> +  }
> +
> +  // obtain page table base
> +  FirstLevelTable = (ARM_FIRST_LEVEL_DESCRIPTOR *)ArmGetTTBR0BaseAddress ();
> +
> +  // calculate index into first level translation table for start of modification
> +  FirstLevelIdx = TT_DESCRIPTOR_SECTION_BASE_ADDRESS(BaseAddress) >> TT_DESCRIPTOR_SECTION_BASE_SHIFT;
> +  ASSERT (FirstLevelIdx < TRANSLATION_TABLE_SECTION_COUNT);
> +
> +  // calculate number of 1MB first level entries this applies to
> +  NumSections = Length / TT_DESCRIPTOR_SECTION_SIZE;
> +
> +  // iterate through each descriptor
> +  for(i=0; i<NumSections; i++) {
> +    CurrentDescriptor = FirstLevelTable[FirstLevelIdx + i];
> +
> +    // has this descriptor already been coverted to pages?
> +    if (TT_DESCRIPTOR_SECTION_TYPE_IS_PAGE_TABLE(CurrentDescriptor)) {
> +      // forward this 1MB range to page table function instead
> +      Status = UpdatePageEntries ((FirstLevelIdx + i) << TT_DESCRIPTOR_SECTION_BASE_SHIFT, TT_DESCRIPTOR_SECTION_SIZE, Attributes, VirtualMask);
> +    } else {
> +      // still a section entry
> +
> +      // mask off appropriate fields
> +      Descriptor = CurrentDescriptor & ~EntryMask;
> +
> +      // mask in new attributes and/or permissions
> +      Descriptor |= EntryValue;
> +      if (VirtualMask != 0) {
> +        Descriptor &= ~VirtualMask;
> +      }
> +
> +      if (CurrentDescriptor  != Descriptor) {
> +        Mva = (VOID *)(UINTN)(((UINTN)FirstLevelTable) << TT_DESCRIPTOR_SECTION_BASE_SHIFT);
> +        if ((CurrentDescriptor & TT_DESCRIPTOR_SECTION_CACHEABLE_MASK) == TT_DESCRIPTOR_SECTION_CACHEABLE_MASK) {
> +          // The current section mapping is cacheable so Clean/Invalidate the MVA of the section
> +          // Note assumes switch(Attributes), not ARMv7 possabilities
> +          WriteBackInvalidateDataCacheRange (Mva, SIZE_1MB);
> +        }
> +
> +        // Only need to update if we are changing the descriptor
> +        FirstLevelTable[FirstLevelIdx + i] = Descriptor;
> +        ArmUpdateTranslationTableEntry ((VOID *)&FirstLevelTable[FirstLevelIdx + i], Mva);
> +      }
> +
> +      Status = EFI_SUCCESS;
> +    }
> +  }
> +
> +  return Status;
> +}
> +
> +EFI_STATUS
> +ArmSetMemoryAttributes (
> +  IN EFI_PHYSICAL_ADDRESS      BaseAddress,
> +  IN UINT64                    Length,
> +  IN UINT64                    Attributes,
> +  IN EFI_PHYSICAL_ADDRESS      VirtualMask
> +  )
> +{
> +  EFI_STATUS    Status;
> +  UINT64        ChunkLength;
> +  BOOLEAN       FlushTlbs;
> +
> +  FlushTlbs = FALSE;
> +  while (Length > 0) {
> +    if ((BaseAddress % TT_DESCRIPTOR_SECTION_SIZE == 0) &&
> +        Length >= TT_DESCRIPTOR_SECTION_SIZE) {
> +
> +      ChunkLength = Length - Length % TT_DESCRIPTOR_SECTION_SIZE;
> +
> +      DEBUG ((DEBUG_PAGE | DEBUG_INFO,
> +        "SetMemoryAttributes(): MMU section 0x%lx length 0x%lx to %lx\n",
> +        BaseAddress, ChunkLength, Attributes));
> +
> +      Status = UpdateSectionEntries (BaseAddress, ChunkLength, Attributes,
> +                 VirtualMask);
> +
> +      FlushTlbs = TRUE;
> +    } else {
> +
> +      //
> +      // Process page by page until the next section boundary, but only if
> +      // we have more than a section's worth of area to deal with after that.
> +      //
> +      ChunkLength = TT_DESCRIPTOR_SECTION_SIZE -
> +                    (BaseAddress % TT_DESCRIPTOR_SECTION_SIZE);
> +      if (ChunkLength + TT_DESCRIPTOR_SECTION_SIZE > Length) {
> +        ChunkLength = Length;
> +      }
> +
> +      DEBUG ((DEBUG_PAGE | DEBUG_INFO,
> +        "SetMemoryAttributes(): MMU page 0x%lx length 0x%lx to %lx\n",
> +        BaseAddress, ChunkLength, Attributes));
> +
> +      Status = UpdatePageEntries (BaseAddress, ChunkLength, Attributes,
> +                 VirtualMask);
> +    }
> +
> +    if (EFI_ERROR (Status)) {
> +      break;
> +    }
> +
> +    BaseAddress += ChunkLength;
> +    Length -= ChunkLength;
> +  }
> +
> +  if (FlushTlbs) {
> +    ArmInvalidateTlb ();
> +  }
> +  return Status;
> +}
> +
>  RETURN_STATUS
>  ArmSetMemoryRegionNoExec (
>    IN  EFI_PHYSICAL_ADDRESS      BaseAddress,
> -- 
> 2.7.4
> 


  reply	other threads:[~2017-03-06 16:03 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-01 16:31 [PATCH 0/5] ArmPkg, ArmVirtPkg ARM: enable non-executable stack Ard Biesheuvel
2017-03-01 16:31 ` [PATCH 1/5] ArmPkg/ArmMmuLib AARCH64: use correct return type for exported functions Ard Biesheuvel
2017-03-06 14:57   ` Leif Lindholm
2017-03-01 16:31 ` [PATCH 2/5] ArmPkg: move ARM version of SetMemoryAttributes to ArmMmuLib Ard Biesheuvel
2017-03-06 16:03   ` Leif Lindholm [this message]
2017-03-06 16:05     ` Ard Biesheuvel
2017-03-06 16:21       ` Leif Lindholm
2017-03-01 16:31 ` [PATCH 3/5] ArmPkg/ArmMmuLib: remove VirtualMask arg from ArmSetMemoryAttributes Ard Biesheuvel
2017-03-06 16:06   ` Leif Lindholm
2017-03-01 16:31 ` [PATCH 4/5] ArmPkg/ArmMmuLib ARM: implement memory permission control routines Ard Biesheuvel
2017-03-06 16:11   ` Leif Lindholm
2017-03-01 16:31 ` [PATCH 5/5] ArmVirtPkg: enable non-executable DXE stack for all platforms Ard Biesheuvel
2017-03-01 19:10   ` Laszlo Ersek
2017-03-01 19:10     ` Ard Biesheuvel

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