Optimization for Ventoy2Disk.exe

[Ventoy.git] / EDK2 / efiffs / mod / src / file.c

/* file.c - SimpleFileIo Interface */
/*
 *  Copyright © 2014-2017 Pete Batard <pete@akeo.ie>
 *  Based on iPXE's efi_driver.c and efi_file.c:
 *  Copyright © 2011,2013 Michael Brown <mbrown@fensystems.co.uk>.
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "driver.h"

/**
 * Get EFI file name (for debugging)
 *
 * @v file                      EFI file
 * @ret Name            Name
 */
static const CHAR16 *
FileName(EFI_GRUB_FILE *File)
{
        EFI_STATUS Status;
        static CHAR16 Path[MAX_PATH];

        Status = Utf8ToUtf16NoAlloc(File->path, Path, sizeof(Path));
        if (EFI_ERROR(Status)) {
                PrintStatusError(Status, L"Could not convert filename to UTF16");
                return NULL;
        }

        return Path;
}

/* Simple hook to populate the timestamp and directory flag when opening a file */
static INT32
InfoHook(const CHAR8 *name, const GRUB_DIRHOOK_INFO *Info, VOID *Data)
{
        EFI_GRUB_FILE *File = (EFI_GRUB_FILE *) Data;

        /* Look for a specific file */
        if (strcmpa(name, File->basename) != 0)
                return 0;

        File->IsDir = (BOOLEAN) (Info->Dir);
        if (Info->MtimeSet)
                File->Mtime = Info->Mtime;

        return 0;
}

/**
 * Open file
 *
 * @v This                      File handle
 * @ret new                     New file handle
 * @v Name                      File name
 * @v Mode                      File mode
 * @v Attributes        File attributes (for newly-created files)
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileOpen(EFI_FILE_HANDLE This, EFI_FILE_HANDLE *New,
                CHAR16 *Name, UINT64 Mode, UINT64 Attributes)
{
        EFI_STATUS Status;
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);
        EFI_GRUB_FILE *NewFile;

        // TODO: Use dynamic buffers?
        char path[MAX_PATH], clean_path[MAX_PATH], *dirname;
        INTN i, len;
        BOOLEAN AbsolutePath = (*Name == L'\\');

        PrintInfo(L"Open(" PERCENT_P L"%s, \"%s\")\n", (UINTN) This,
                        IS_ROOT(File)?L" <ROOT>":L"", Name);

        /* Fail unless opening read-only */
        if (Mode != EFI_FILE_MODE_READ) {
                PrintWarning(L"File '%s' can only be opened in read-only mode\n", Name);
                return EFI_WRITE_PROTECTED;
        }

        /* Additional failures */
        if ((StrCmp(Name, L"..") == 0) && IS_ROOT(File)) {
                PrintInfo(L"Trying to open <ROOT>'s parent\n");
                return EFI_NOT_FOUND;
        }

        /* See if we're trying to reopen current (which the EFI Shell insists on doing) */
        if ((*Name == 0) || (StrCmp(Name, L".") == 0)) {
                PrintInfo(L"  Reopening %s\n", IS_ROOT(File)?L"<ROOT>":FileName(File));
                File->RefCount++;
                *New = This;
                PrintInfo(L"  RET: " PERCENT_P L"\n", (UINTN) *New);
                return EFI_SUCCESS;
        }

        /* If we have an absolute path, don't bother completing with the parent */
        if (AbsolutePath) {
                len = 0;
        } else {
                strcpya(path, File->path);
                len = strlena(path);
                /* Add delimiter if needed */
                if ((len == 0) || (path[len-1] != '/'))
                        path[len++] = '/';
        }

        /* Copy the rest of the path (converted to UTF-8) */
        Status = Utf16ToUtf8NoAlloc(Name, &path[len], sizeof(path) - len);
        if (EFI_ERROR(Status)) {
                PrintStatusError(Status, L"Could not convert path to UTF-8");
                return Status;
        }
        /* Convert the delimiters */
        for (i = strlena(path) - 1 ; i >= len; i--) {
                if (path[i] == '\\')
                        path[i] = '/';
        }

        /* We only want to handle with absolute paths */
        clean_path[0] = '/';
        /* Find out if we're dealing with root by removing the junk */
        CopyPathRelative(&clean_path[1], path, MAX_PATH - 1);
        if (clean_path[1] == 0) {
                /* We're dealing with the root */
                PrintInfo(L"  Reopening <ROOT>\n");
                *New = &File->FileSystem->RootFile->EfiFile;
                /* Must make sure that DirIndex is reset too (NB: no concurrent access!) */
                File->FileSystem->RootFile->DirIndex = 0;
                PrintInfo(L"  RET: " PERCENT_P L"\n", (UINTN) *New);
                return EFI_SUCCESS;
        }

        // TODO: eventually we should seek for already opened files and increase RefCount
        /* Allocate and initialise an instance of a file */
        Status = GrubCreateFile(&NewFile, File->FileSystem);
        if (EFI_ERROR(Status)) {
                PrintStatusError(Status, L"Could not instantiate file");
                return Status;
        }

        NewFile->path = AllocatePool(strlena(clean_path)+1);
        if (NewFile->path == NULL) {
                GrubDestroyFile(NewFile);
                PrintError(L"Could not instantiate path\n");
                return EFI_OUT_OF_RESOURCES;
        }
        strcpya(NewFile->path, clean_path);

        /* Isolate the basename and dirname */
        for (i = strlena(clean_path) - 1; i >= 0; i--) {
                if (clean_path[i] == '/') {
                        clean_path[i] = 0;
                        break;
                }
        }
        dirname = (i <= 0) ? "/" : clean_path;
        NewFile->basename = &NewFile->path[i+1];

        /* Find if we're working with a directory and fill the grub timestamp */
        Status = GrubDir(NewFile, dirname, InfoHook, (VOID *) NewFile);
        if (EFI_ERROR(Status)) {
                if (Status != EFI_NOT_FOUND)
                        PrintStatusError(Status, L"Could not get file attributes for '%s'", Name);
                FreePool(NewFile->path);
                GrubDestroyFile(NewFile);
                return Status;
        }

        /* Finally we can call on GRUB open() if it's a regular file */
        if (!NewFile->IsDir) {
                Status = GrubOpen(NewFile);
                if (EFI_ERROR(Status)) {
                        if (Status != EFI_NOT_FOUND)
                                PrintStatusError(Status, L"Could not open file '%s'", Name);
                        FreePool(NewFile->path);
                        GrubDestroyFile(NewFile);
                        return Status;
                }
        }

        NewFile->RefCount++;
        *New = &NewFile->EfiFile;

        PrintInfo(L"  RET: " PERCENT_P L"\n", (UINTN) *New);
        return EFI_SUCCESS;
}

/* Ex version */
static EFI_STATUS EFIAPI
FileOpenEx(EFI_FILE_HANDLE This, EFI_FILE_HANDLE *New, CHAR16 *Name,
        UINT64 Mode, UINT64 Attributes, EFI_FILE_IO_TOKEN *Token)
{
        return FileOpen(This, New, Name, Mode, Attributes);
}


/**
 * Close file
 *
 * @v This                      File handle
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileClose(EFI_FILE_HANDLE This)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintInfo(L"Close(" PERCENT_P L"|'%s') %s\n", (UINTN) This, FileName(File),
                IS_ROOT(File)?L"<ROOT>":L"");

        /* Nothing to do it this is the root */
        if (IS_ROOT(File))
                return EFI_SUCCESS;

        if (--File->RefCount == 0) {
                /* Close the file if it's a regular one */
                if (!File->IsDir)
                        GrubClose(File);
                /* NB: basename points into File->path and does not need to be freed */
                if (File->path != NULL)
                        FreePool(File->path);
                GrubDestroyFile(File);
        }

        return EFI_SUCCESS;
}

/**
 * Close and delete file
 *
 * @v This                      File handle
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileDelete(EFI_FILE_HANDLE This)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintError(L"Cannot delete '%s'\n", FileName(File));

        /* Close file */
        FileClose(This);

        /* Warn of failure to delete */
        return EFI_WARN_DELETE_FAILURE;
}

/* GRUB uses a callback for each directory entry, whereas EFI uses repeated
 * firmware generated calls to FileReadDir() to get the info for each entry,
 * so we have to reconcile the twos. For now, we'll re-issue a call to GRUB
 * dir(), and run through all the entries (to find the one we
 * are interested in) multiple times. Maybe later we'll try to optimize this
 * by building a one-off chained list of entries that we can parse...
 */
static INT32
DirHook(const CHAR8 *name, const GRUB_DIRHOOK_INFO *DirInfo, VOID *Data)
{
        EFI_STATUS Status;
        EFI_FILE_INFO *Info = (EFI_FILE_INFO *) Data;
        INT64 *Index = (INT64 *) &Info->FileSize;
        CHAR8 *filename = (CHAR8 *) (UINTN) Info->PhysicalSize;
        EFI_TIME Time = { 1970, 01, 01, 00, 00, 00, 0, 0, 0, 0, 0};

        // Eliminate '.' or '..'
        if ((name[0] ==  '.') && ((name[1] == 0) || ((name[1] == '.') && (name[2] == 0))))
                return 0;

        /* Ignore any entry that doesn't match our index */
        if ((*Index)-- != 0)
                return 0;

        strcpya(filename, name);

        Status = Utf8ToUtf16NoAlloc(filename, Info->FileName, (INTN)(Info->Size - sizeof(EFI_FILE_INFO)));
        if (EFI_ERROR(Status)) {
                if (Status != EFI_BUFFER_TOO_SMALL)
                        PrintStatusError(Status, L"Could not convert directory entry to UTF-8");
                return (INT32) Status;
        }
        /* The Info struct size already accounts for the extra NUL */
        Info->Size = sizeof(*Info) + StrLen(Info->FileName) * sizeof(CHAR16);

        // Oh, and of course GRUB uses a 32 bit signed mtime value (seriously, wtf guys?!?)
        if (DirInfo->MtimeSet)
                GrubTimeToEfiTime(DirInfo->Mtime, &Time);
        CopyMem(&Info->CreateTime, &Time, sizeof(Time));
        CopyMem(&Info->LastAccessTime, &Time, sizeof(Time));
        CopyMem(&Info->ModificationTime, &Time, sizeof(Time));

        Info->Attribute = EFI_FILE_READ_ONLY;
        if (DirInfo->Dir)
                Info->Attribute |= EFI_FILE_DIRECTORY;

        return 0;
}

/**
 * Read directory entry
 *
 * @v file                      EFI file
 * @v Len                       Length to read
 * @v Data                      Data buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS
FileReadDir(EFI_GRUB_FILE *File, UINTN *Len, VOID *Data)
{
        EFI_FILE_INFO *Info = (EFI_FILE_INFO *) Data;
        EFI_STATUS Status;
        /* We temporarily repurpose the FileSize as a *signed* entry index */
        INT64 *Index = (INT64 *) &Info->FileSize;
        /* And PhysicalSize as a pointer to our filename */
        CHAR8 **basename = (CHAR8 **) &Info->PhysicalSize;
        CHAR8 path[MAX_PATH];
        EFI_GRUB_FILE *TmpFile = NULL;
        INTN len;

        /* Unless we can fit our maximum size, forget it */
        if (*Len < sizeof(EFI_FILE_INFO)) {
                *Len = MINIMUM_INFO_LENGTH;
                return EFI_BUFFER_TOO_SMALL;
        }

        /* Populate our Info template */
        ZeroMem(Data, *Len);
        Info->Size = *Len;
        *Index = File->DirIndex;
        strcpya(path, File->path);
        len = strlena(path);
        if (path[len-1] != '/')
                path[len++] = '/';
        *basename = &path[len];

        /* Invoke GRUB's directory listing */
        Status = GrubDir(File, File->path, DirHook, Data);
        if (*Index >= 0) {
                /* No more entries */
                *Len = 0;
                return EFI_SUCCESS;
        }

        if (EFI_ERROR(Status)) {
        if (Status == EFI_BUFFER_TOO_SMALL) {
            *Len = MINIMUM_INFO_LENGTH;
        } else {
                    PrintStatusError(Status, L"Directory listing failed");
        }
                return Status;
        }

        /* Our Index/FileSize must be reset */
        Info->FileSize = 0;
        Info->PhysicalSize = 0;

        /* For regular files, we still need to fill the size */
        if (!(Info->Attribute & EFI_FILE_DIRECTORY)) {
                /* Open the file and read its size */
                Status = GrubCreateFile(&TmpFile, File->FileSystem);
                if (EFI_ERROR(Status)) {
                        PrintStatusError(Status, L"Unable to create temporary file");
                        return Status;
                }
                TmpFile->path = path;

                Status = GrubOpen(TmpFile);
                if (EFI_ERROR(Status)) {
                        // TODO: EFI_NO_MAPPING is returned for links...
                        PrintStatusError(Status, L"Unable to obtain the size of '%s'", Info->FileName);
                        /* Non fatal error */
                } else {
                        Info->FileSize = GrubGetFileSize(TmpFile);
                        Info->PhysicalSize = GrubGetFileSize(TmpFile);
                        GrubClose(TmpFile);
                }
                GrubDestroyFile(TmpFile);
        }

        *Len = (UINTN) Info->Size;
        /* Advance to the next entry */
        File->DirIndex++;

//      PrintInfo(L"  Entry[%d]: '%s' %s\n", File->DirIndex-1, Info->FileName,
//                      (Info->Attribute&EFI_FILE_DIRECTORY)?L"<DIR>":L"");

        return EFI_SUCCESS;
}

/**
 * Read from file
 *
 * @v This                      File handle
 * @v Len                       Length to read
 * @v Data                      Data buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileRead(EFI_FILE_HANDLE This, UINTN *Len, VOID *Data)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintInfo(L"Read(" PERCENT_P L"|'%s', %d) %s\n", (UINTN) This, FileName(File),
                        *Len, File->IsDir?L"<DIR>":L"");

        /* If this is a directory, then fetch the directory entries */
        if (File->IsDir)
                return FileReadDir(File, Len, Data);

        return GrubRead(File, Data, Len);
}

/* Ex version */
static EFI_STATUS EFIAPI
FileReadEx(IN EFI_FILE_PROTOCOL *This, IN OUT EFI_FILE_IO_TOKEN *Token)
{
        return FileRead(This, &(Token->BufferSize), Token->Buffer);
}

/**
 * Write to file
 *
 * @v This                      File handle
 * @v Len                       Length to write
 * @v Data                      Data buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileWrite(EFI_FILE_HANDLE This, UINTN *Len, VOID *Data)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintError(L"Cannot write to '%s'\n", FileName(File));
        return EFI_WRITE_PROTECTED;
}

/* Ex version */
static EFI_STATUS EFIAPI
FileWriteEx(IN EFI_FILE_PROTOCOL *This, IN OUT EFI_FILE_IO_TOKEN *Token)
{
        return FileWrite(This, &(Token->BufferSize), Token->Buffer);
}

/**
 * Set file position
 *
 * @v This                      File handle
 * @v Position          New file position
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileSetPosition(EFI_FILE_HANDLE This, UINT64 Position)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);
        UINT64 FileSize;

        PrintInfo(L"SetPosition(" PERCENT_P L"|'%s', %lld) %s\n", (UINTN) This,
                FileName(File), Position, (File->IsDir)?L"<DIR>":L"");

        /* If this is a directory, reset the Index to the start */
        if (File->IsDir) {
                if (Position != 0)
                        return EFI_INVALID_PARAMETER;
                File->DirIndex = 0;
                return EFI_SUCCESS;
        }

        /* Fail if we attempt to seek past the end of the file (since
         * we do not support writes).
         */
        FileSize = GrubGetFileSize(File);
        if (Position > FileSize) {
                PrintError(L"'%s': Cannot seek to #%llx of %llx\n",
                                FileName(File), Position, FileSize);
                return EFI_UNSUPPORTED;
        }

        /* Set position */
        GrubSetFileOffset(File, Position);
        PrintDebug(L"'%s': Position set to %llx\n",
                        FileName(File), Position);

        return EFI_SUCCESS;
}

/**
 * Get file position
 *
 * @v This                      File handle
 * @ret Position        New file position
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileGetPosition(EFI_FILE_HANDLE This, UINT64 *Position)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintInfo(L"GetPosition(" PERCENT_P L"|'%s', %lld)\n", (UINTN) This, FileName(File));

        if (File->IsDir)
                *Position = File->DirIndex;
        else
                *Position = GrubGetFileOffset(File);
        return EFI_SUCCESS;
}

/**
 * Get file information
 *
 * @v This                      File handle
 * @v Type                      Type of information
 * @v Len                       Buffer size
 * @v Data                      Buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileGetInfo(EFI_FILE_HANDLE This, EFI_GUID *Type, UINTN *Len, VOID *Data)
{
        EFI_STATUS Status;
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);
        EFI_FILE_SYSTEM_INFO *FSInfo = (EFI_FILE_SYSTEM_INFO *) Data;
        EFI_FILE_INFO *Info = (EFI_FILE_INFO *) Data;
        EFI_FILE_SYSTEM_VOLUME_LABEL_INFO *VLInfo = (EFI_FILE_SYSTEM_VOLUME_LABEL_INFO *)Data;
        EFI_TIME Time;
        CHAR8* label;
        UINTN tmpLen;

        PrintInfo(L"GetInfo(" PERCENT_P L"|'%s', %d) %s\n", (UINTN) This,
                FileName(File), *Len, File->IsDir?L"<DIR>":L"");

        /* Determine information to return */
        if (CompareMem(Type, &gEfiFileInfoGuid, sizeof(*Type)) == 0) {

                /* Fill file information */
                PrintExtra(L"Get regular file information\n");
                if (*Len < sizeof(EFI_FILE_INFO)) {
                        *Len = MINIMUM_INFO_LENGTH;
                        return EFI_BUFFER_TOO_SMALL;
                }

                ZeroMem(Data, sizeof(EFI_FILE_INFO));

                Info->Attribute = EFI_FILE_READ_ONLY;
                GrubTimeToEfiTime(File->Mtime, &Time);
                CopyMem(&Info->CreateTime, &Time, sizeof(Time));
                CopyMem(&Info->LastAccessTime, &Time, sizeof(Time));
                CopyMem(&Info->ModificationTime, &Time, sizeof(Time));

                if (File->IsDir) {
                        Info->Attribute |= EFI_FILE_DIRECTORY;
                } else {
                        Info->FileSize = GrubGetFileSize(File);
                        Info->PhysicalSize = GrubGetFileSize(File);
                }

                tmpLen = (UINTN)(Info->Size - sizeof(EFI_FILE_INFO) - 1);
                Status = Utf8ToUtf16NoAllocUpdateLen(File->basename, Info->FileName, &tmpLen);
                if (EFI_ERROR(Status)) {
                        if (Status != EFI_BUFFER_TOO_SMALL) {
                                PrintStatusError(Status, L"Could not convert basename to UTF-16");
            } else {
                *Len = MINIMUM_INFO_LENGTH;
            }
                        return Status;
                }

                /* The Info struct size already accounts for the extra NUL */
                Info->Size = sizeof(EFI_FILE_INFO) + tmpLen;
                *Len = (INTN)Info->Size;
                return EFI_SUCCESS;

        } else if (CompareMem(Type, &gEfiFileSystemInfoGuid, sizeof(*Type)) == 0) {

                /* Get file system information */
                PrintExtra(L"Get file system information\n");
                if (*Len < sizeof(EFI_FILE_SYSTEM_INFO)) {
                        *Len = MINIMUM_FS_INFO_LENGTH;
                        return EFI_BUFFER_TOO_SMALL;
                }

                ZeroMem(Data, sizeof(EFI_FILE_INFO));
                FSInfo->Size = *Len;
                FSInfo->ReadOnly = 1;
                /* NB: This should really be cluster size, but we don't have access to that */
                if (File->FileSystem->BlockIo2 != NULL) {
                        FSInfo->BlockSize = File->FileSystem->BlockIo2->Media->BlockSize;
                } else {
                        FSInfo->BlockSize = File->FileSystem->BlockIo->Media->BlockSize;
                }
                if (FSInfo->BlockSize  == 0) {
                        PrintWarning(L"Corrected Media BlockSize\n");
                        FSInfo->BlockSize = 512;
                }
                if (File->FileSystem->BlockIo2 != NULL) {
                        FSInfo->VolumeSize = (File->FileSystem->BlockIo2->Media->LastBlock + 1) *
                                FSInfo->BlockSize;
                } else {
                        FSInfo->VolumeSize = (File->FileSystem->BlockIo->Media->LastBlock + 1) *
                                FSInfo->BlockSize;
                }
                /* No idea if we can easily get this for GRUB, and the device is RO anyway */
                FSInfo->FreeSpace = 0;

                Status = GrubLabel(File, &label);
                if (EFI_ERROR(Status)) {
                        PrintStatusError(Status, L"Could not read disk label");
                        FSInfo->VolumeLabel[0] = 0;
                        *Len = sizeof(EFI_FILE_SYSTEM_INFO);
                } else {
                        tmpLen = (INTN)(FSInfo->Size - sizeof(EFI_FILE_SYSTEM_INFO) - 1);
                        Status = Utf8ToUtf16NoAllocUpdateLen(label, FSInfo->VolumeLabel, &tmpLen);
                        if (EFI_ERROR(Status)) {
                                if (Status != EFI_BUFFER_TOO_SMALL) {
                                        PrintStatusError(Status, L"Could not convert label to UTF-16");
                } else {
                    *Len = MINIMUM_FS_INFO_LENGTH;
                }
                                return Status;
                        }
                        FSInfo->Size = sizeof(EFI_FILE_SYSTEM_INFO) - 1 + tmpLen;
                        *Len = (INTN)FSInfo->Size;
                }
                return EFI_SUCCESS;

        } else if (CompareMem(Type, &gEfiFileSystemVolumeLabelInfoIdGuid, sizeof(*Type)) == 0) {

                /* Get the volume label */
                Status = GrubLabel(File, &label);
                if (EFI_ERROR(Status)) {
                        PrintStatusError(Status, L"Could not read disk label");
                }
                else {
                        Status = Utf8ToUtf16NoAllocUpdateLen(label, VLInfo->VolumeLabel, Len);
                        if (EFI_ERROR(Status)) {
                                if (Status != EFI_BUFFER_TOO_SMALL)
                                        PrintStatusError(Status, L"Could not convert label to UTF-16");
                                return Status;
                        }
                }
                return EFI_SUCCESS;

        } else {

                Print(L"'%s': Cannot get information of type ", FileName(File));
                PrintGuid(Type);
                Print(L"\n");
                return EFI_UNSUPPORTED;

        }
}

/**
 * Set file information
 *
 * @v This                      File handle
 * @v Type                      Type of information
 * @v Len                       Buffer size
 * @v Data                      Buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileSetInfo(EFI_FILE_HANDLE This, EFI_GUID *Type, UINTN Len, VOID *Data)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        Print(L"Cannot set information of type ");
        PrintGuid(Type);
        Print(L" for file '%s'\n", FileName(File));

        return EFI_WRITE_PROTECTED;
}

/**
 * Flush file modified data
 *
 * @v This                      File handle
 * @v Type                      Type of information
 * @v Len                       Buffer size
 * @v Data                      Buffer
 * @ret Status          EFI status code
 */
static EFI_STATUS EFIAPI
FileFlush(EFI_FILE_HANDLE This)
{
        EFI_GRUB_FILE *File = _CR(This, EFI_GRUB_FILE, EfiFile);

        PrintInfo(L"Flush(" PERCENT_P L"|'%s')\n", (UINTN) This, FileName(File));
        return EFI_SUCCESS;
}

/* Ex version */
static EFI_STATUS EFIAPI
FileFlushEx(EFI_FILE_HANDLE This, EFI_FILE_IO_TOKEN *Token)
{
        return FileFlush(This);
}

/**
 * Open root directory
 *
 * @v This                      EFI simple file system
 * @ret Root            File handle for the root directory
 * @ret Status          EFI status code
 */
EFI_STATUS EFIAPI
FileOpenVolume(EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *This, EFI_FILE_HANDLE *Root)
{
        EFI_FS *FSInstance = _CR(This, EFI_FS, FileIoInterface);

        PrintInfo(L"OpenVolume\n");
        *Root = &FSInstance->RootFile->EfiFile;

        return EFI_SUCCESS;
}

/**
 * Install the EFI simple file system protocol
 * If successful this call instantiates a new FS#: drive, that is made
 * available on the next 'map -r'. Note that all this call does is add
 * the FS protocol. OpenVolume won't be called until a process tries
 * to access a file or the root directory on the volume.
 */
EFI_STATUS
FSInstall(EFI_FS *This, EFI_HANDLE ControllerHandle)
{
        EFI_STATUS Status;

        /* Check if it's a filesystem we can handle */
        if (!GrubFSProbe(This))
                return EFI_UNSUPPORTED;

        PrintInfo(L"FSInstall: %s\n", This->DevicePathString);

        /* Initialize the root handle */
        Status = GrubCreateFile(&This->RootFile, This);
        if (EFI_ERROR(Status)) {
                PrintStatusError(Status, L"Could not create root file");
                return Status;
        }

        /* Setup the EFI part */
        This->RootFile->EfiFile.Revision = EFI_FILE_PROTOCOL_REVISION2;
        This->RootFile->EfiFile.Open = FileOpen;
        This->RootFile->EfiFile.Close = FileClose;
        This->RootFile->EfiFile.Delete = FileDelete;
        This->RootFile->EfiFile.Read = FileRead;
        This->RootFile->EfiFile.Write = FileWrite;
        This->RootFile->EfiFile.GetPosition = FileGetPosition;
        This->RootFile->EfiFile.SetPosition = FileSetPosition;
        This->RootFile->EfiFile.GetInfo = FileGetInfo;
        This->RootFile->EfiFile.SetInfo = FileSetInfo;
        This->RootFile->EfiFile.Flush = FileFlush;
        This->RootFile->EfiFile.OpenEx = FileOpenEx;
        This->RootFile->EfiFile.ReadEx = FileReadEx;
        This->RootFile->EfiFile.WriteEx = FileWriteEx;
        This->RootFile->EfiFile.FlushEx = FileFlushEx;

        /* Setup the other attributes */
        This->RootFile->path = "/";
        This->RootFile->basename = &This->RootFile->path[1];
        This->RootFile->IsDir = TRUE;

        /* Install the simple file system protocol. */
        Status = BS->InstallMultipleProtocolInterfaces(&ControllerHandle,
                        &gEfiSimpleFileSystemProtocolGuid, &This->FileIoInterface,
                        NULL);
        if (EFI_ERROR(Status)) {
                PrintStatusError(Status, L"Could not install simple file system protocol");
                return Status;
        }

        return EFI_SUCCESS;
}

/* Uninstall EFI simple file system protocol */
VOID
FSUninstall(EFI_FS *This, EFI_HANDLE ControllerHandle)
{
        PrintInfo(L"FSUninstall: %s\n", This->DevicePathString);

        BS->UninstallMultipleProtocolInterfaces(ControllerHandle,
                        &gEfiSimpleFileSystemProtocolGuid, &This->FileIoInterface,
                        NULL);
}