OvmfPkg/VirtioFsDxe: add EFI_FILE_INFO cache fields to VIRTIO_FS_FILE

For reading through a directory stream with tolerable performance, we'll
have to call FUSE_READDIRPLUS each time with such a buffer that can
deliver a good number of variable size records
(VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE elements). Every time we'll do that,
we'll turn the whole bunch into an array of EFI_FILE_INFOs immediately.
EFI_FILE_PROTOCOL.Read() invocations (on directories) will be served from
this EFI_FILE_INFO cache.

Add the fields for the EFI_FILE_INFO cache to VIRTIO_FS_FILE:
- initialize them in Open() and OpenVolume(),
- release the cache in Close() and Delete(),
- also release the cache when the directory is rewound, in SetPosition().

Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3097
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20201216211125.19496-36-lersek@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>

6 files changed, 42 insertions, 0 deletions

diff --git a/OvmfPkg/VirtioFsDxe/SimpleFsClose.c b/OvmfPkg/VirtioFsDxe/SimpleFsClose.c
index 04b4f2c382..4c1cf52112 100644
--- a/OvmfPkg/VirtioFsDxe/SimpleFsClose.c
+++ b/OvmfPkg/VirtioFsDxe/SimpleFsClose.c
@@ -60,6 +60,9 @@ VirtioFsSimpleFileClose (
   RemoveEntryList (&VirtioFsFile->OpenFilesEntry);

 

   FreePool (VirtioFsFile->CanonicalPathname);

+  if (VirtioFsFile->FileInfoArray != NULL) {

+    FreePool (VirtioFsFile->FileInfoArray);

+  }

   FreePool (VirtioFsFile);

   return EFI_SUCCESS;

 }

diff --git a/OvmfPkg/VirtioFsDxe/SimpleFsDelete.c b/OvmfPkg/VirtioFsDxe/SimpleFsDelete.c
index 76cfee5bce..76a868b3c2 100644
--- a/OvmfPkg/VirtioFsDxe/SimpleFsDelete.c
+++ b/OvmfPkg/VirtioFsDxe/SimpleFsDelete.c
@@ -102,6 +102,9 @@ VirtioFsSimpleFileDelete (
   RemoveEntryList (&VirtioFsFile->OpenFilesEntry);

 

   FreePool (VirtioFsFile->CanonicalPathname);

+  if (VirtioFsFile->FileInfoArray != NULL) {

+    FreePool (VirtioFsFile->FileInfoArray);

+  }

   FreePool (VirtioFsFile);

   return Status;

 }

diff --git a/OvmfPkg/VirtioFsDxe/SimpleFsOpen.c b/OvmfPkg/VirtioFsDxe/SimpleFsOpen.c
index 7c50ce9c0e..d73d23fe86 100644
--- a/OvmfPkg/VirtioFsDxe/SimpleFsOpen.c
+++ b/OvmfPkg/VirtioFsDxe/SimpleFsOpen.c
@@ -482,6 +482,10 @@ VirtioFsSimpleFileOpen (
   NewVirtioFsFile->FilePosition           = 0;

   NewVirtioFsFile->NodeId                 = NewNodeId;

   NewVirtioFsFile->FuseHandle             = NewFuseHandle;

+  NewVirtioFsFile->FileInfoArray          = NULL;

+  NewVirtioFsFile->SingleFileInfoSize     = 0;

+  NewVirtioFsFile->NumFileInfo            = 0;

+  NewVirtioFsFile->NextFileInfo           = 0;

 

   //

   // One more file is now open for the filesystem.

diff --git a/OvmfPkg/VirtioFsDxe/SimpleFsOpenVolume.c b/OvmfPkg/VirtioFsDxe/SimpleFsOpenVolume.c
index 1181191d27..058e7a41ab 100644
--- a/OvmfPkg/VirtioFsDxe/SimpleFsOpenVolume.c
+++ b/OvmfPkg/VirtioFsDxe/SimpleFsOpenVolume.c
@@ -75,6 +75,10 @@ VirtioFsOpenVolume (
   VirtioFsFile->FilePosition           = 0;

   VirtioFsFile->NodeId                 = VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID;

   VirtioFsFile->FuseHandle             = RootDirHandle;

+  VirtioFsFile->FileInfoArray          = NULL;

+  VirtioFsFile->SingleFileInfoSize     = 0;

+  VirtioFsFile->NumFileInfo            = 0;

+  VirtioFsFile->NextFileInfo           = 0;

 

   //

   // One more file open for the filesystem.

diff --git a/OvmfPkg/VirtioFsDxe/SimpleFsSetPosition.c b/OvmfPkg/VirtioFsDxe/SimpleFsSetPosition.c
index ac62853026..a548012d9c 100644
--- a/OvmfPkg/VirtioFsDxe/SimpleFsSetPosition.c
+++ b/OvmfPkg/VirtioFsDxe/SimpleFsSetPosition.c
@@ -7,6 +7,8 @@
   SPDX-License-Identifier: BSD-2-Clause-Patent

 **/

 

+#include <Library/MemoryAllocationLib.h> // FreePool()

+

 #include "VirtioFsDxe.h"

 

 EFI_STATUS

@@ -31,6 +33,13 @@ VirtioFsSimpleFileSetPosition (
       return EFI_UNSUPPORTED;

     }

     VirtioFsFile->FilePosition = 0;

+    if (VirtioFsFile->FileInfoArray != NULL) {

+      FreePool (VirtioFsFile->FileInfoArray);

+      VirtioFsFile->FileInfoArray = NULL;

+    }

+    VirtioFsFile->SingleFileInfoSize = 0;

+    VirtioFsFile->NumFileInfo        = 0;

+    VirtioFsFile->NextFileInfo       = 0;

     return EFI_SUCCESS;

   }

 

diff --git a/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h b/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
index 2b419048c2..a704acdd52 100644
--- a/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
+++ b/OvmfPkg/VirtioFsDxe/VirtioFsDxe.h
@@ -48,6 +48,11 @@
 #define VIRTIO_FS_MAX_PATHNAME_LENGTH ((UINTN)65535)

 

 //

+// Maximum value for VIRTIO_FS_FILE.NumFileInfo.

+//

+#define VIRTIO_FS_FILE_MAX_FILE_INFO 256

+

+//

 // Filesystem label encoded in UCS-2, transformed from the UTF-8 representation

 // in "VIRTIO_FS_CONFIG.Tag", and NUL-terminated. Only the printable ASCII code

 // points (U+0020 through U+007E) are supported.

@@ -154,6 +159,20 @@ typedef struct {
   //

   UINT64 NodeId;

   UINT64 FuseHandle;

+  //

+  // EFI_FILE_INFO objects cached for an in-flight directory read.

+  //

+  // For reading through a directory stream with tolerable performance, we have

+  // to call FUSE_READDIRPLUS each time with such a buffer that can deliver a

+  // good number of variable size records (VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE

+  // elements). Every time we do that, we turn the whole bunch into an array of

+  // EFI_FILE_INFOs immediately. EFI_FILE_PROTOCOL.Read() invocations (on

+  // directories) will be served from this EFI_FILE_INFO cache.

+  //

+  UINT8 *FileInfoArray;

+  UINTN SingleFileInfoSize;

+  UINTN NumFileInfo;

+  UINTN NextFileInfo;

 } VIRTIO_FS_FILE;

 

 #define VIRTIO_FS_FILE_FROM_SIMPLE_FILE(SimpleFileReference) \