audk/OvmfPkg/VirtioFsDxe/SimpleFsDelete.c

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OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
/** @file
EFI_FILE_PROTOCOL.Delete() member function for the Virtio Filesystem driver.
Copyright (C) 2020, Red Hat, Inc.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Library/BaseLib.h> // RemoveEntryList()
#include <Library/MemoryAllocationLib.h> // FreePool()
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
#include "VirtioFsDxe.h"
EFI_STATUS
EFIAPI
VirtioFsSimpleFileDelete (
IN EFI_FILE_PROTOCOL *This
)
{
VIRTIO_FS_FILE *VirtioFsFile;
VIRTIO_FS *VirtioFs;
EFI_STATUS Status;
VirtioFsFile = VIRTIO_FS_FILE_FROM_SIMPLE_FILE (This);
VirtioFs = VirtioFsFile->OwnerFs;
//
// All actions in this function are "best effort"; the UEFI spec requires
// EFI_FILE_PROTOCOL.Delete() to release resources unconditionally. If a step
// related to removing the file fails, it's only reflected in the return
// status (EFI_WARN_DELETE_FAILURE rather than EFI_SUCCESS).
//
// Release, remove, and (if needed) forget. We don't waste time flushing and
// syncing; if the EFI_FILE_PROTOCOL user cares enough, they should keep the
// parent directory open until after this function call returns, and then
// force a sync on *that* EFI_FILE_PROTOCOL instance, using either the
// Flush() member function, or the Close() member function.
//
// If any action fails below, we still try the others.
//
VirtioFsFuseReleaseFileOrDir (VirtioFs, VirtioFsFile->NodeId,
VirtioFsFile->FuseHandle, VirtioFsFile->IsDirectory);
//
// VirtioFsFile->FuseHandle is gone at this point, but VirtioFsFile->NodeId
// is still valid. Continue with removing the file or directory. The result
// of this operation determines the return status of the function.
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
//
// TODO
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
//
Status = EFI_WARN_DELETE_FAILURE;
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
//
// Finally, if we've known VirtioFsFile->NodeId from a lookup, then we should
// also ask the server to forget it *once*.
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
2020-12-16 22:10:48 +01:00
//
if (VirtioFsFile->NodeId != VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID) {
VirtioFsFuseForget (VirtioFs, VirtioFsFile->NodeId);
}
//
// One fewer file left open for the owner filesystem.
//
RemoveEntryList (&VirtioFsFile->OpenFilesEntry);
FreePool (VirtioFsFile->CanonicalPathname);
FreePool (VirtioFsFile);
return Status;
OvmfPkg/VirtioFsDxe: implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() With the help of the VirtioFsFuseOpenDir() and VirtioFsFuseReleaseFileOrDir() functions introduced previously, we can now open and close the root directory. So let's implement EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(). OpenVolume() creates a new EFI_FILE_PROTOCOL object -- a reference to the root directory of the filesystem. Thus, we have to start tracking references to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL, lest we unbind the virtio-fs device while files are open. There are two methods that release an EFI_FILE_PROTOCOL object: the Close() and the Delete() member functions. In particular, they are not allowed to fail with regard to resource management -- they must release resources unconditionally. Thus, for rolling back the resource accounting that we do in EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume(), we have to implement the first versions of EFI_FILE_PROTOCOL.Close() and EFI_FILE_PROTOCOL.Delete() in this patch as well. With this patch applied, the UEFI shell can enter the root directory of the Virtio Filesystem (such as with the "FS3:" shell command), and the "DIR" shell command exercises FUSE_OPENDIR and FUSE_RELEASEDIR, according to the virtiofsd log. The "DIR" command reports the root directory as if it were empty; probably because at this time, we only allow the shell to open and to close the root directory, but not to read it. 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: <20201216211125.19496-12-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
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}