CfgUSBLoader/lib/libext2fs/source/gekko_io.c

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/**
* gekko_io.c - Gekko style disk io functions.
*
* Copyright (c) 2009 Rhys "Shareese" Koedijk
* Copyright (c) 2010 Dimok
*
* This program/include file 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 2 of the License, or
* (at your option) any later version.
*
* This program/include file 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, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <gccore.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <sys/stat.h>
#include <limits.h>
#include <locale.h>
#include "gekko_io.h"
#include "bitops.h"
#include "ext2_fs.h"
#include "ext2fs.h"
#include "ext2_internal.h"
#include "disc_cache.h"
#include "mem_allocate.h"
#define DEV_FD(dev) ((gekko_fd *) dev->private_data)
/* Prototypes */
static s64 device_gekko_io_readbytes(io_channel dev, s64 offset, s64 count, void *buf);
static bool device_gekko_io_readsectors(io_channel dev, sec_t sector, sec_t numSectors, void* buffer);
static s64 device_gekko_io_writebytes(io_channel dev, s64 offset, s64 count, const void *buf);
static bool device_gekko_io_writesectors(io_channel dev, sec_t sector, sec_t numSectors, const void* buffer);
/**
*
*/
static errcode_t device_gekko_io_open(const char *name, int flags, io_channel *dev)
{
// Get the device driver descriptor
gekko_fd *fd = DEV_FD((*dev));
if (!fd) {
errno = EBADF;
return -1;
}
// Get the device interface
const DISC_INTERFACE* interface = fd->interface;
if (!interface) {
errno = ENODEV;
return -1;
}
// Start the device interface and ensure that it is inserted
if (!interface->startup()) {
ext2_log_trace("device failed to start\n");
errno = EIO;
return -1;
}
if (!interface->isInserted()) {
ext2_log_trace("device media is not inserted\n");
errno = EIO;
return -1;
}
struct ext2_super_block * super = (struct ext2_super_block *) mem_alloc(SUPERBLOCK_SIZE); //1024 bytes
if(!super)
{
ext2_log_trace("no memory for superblock");
errno = ENOMEM;
return -1;
}
// Check that there is a valid EXT boot sector at the start of the device
if (!interface->readSectors(fd->startSector+SUPERBLOCK_OFFSET/BYTES_PER_SECTOR, SUPERBLOCK_SIZE/BYTES_PER_SECTOR, super))
{
ext2_log_trace("read failure @ sector %d\n", fd->startSector);
errno = EROFS;
mem_free(super);
return -1;
}
if(ext2fs_le16_to_cpu(super->s_magic) != EXT2_SUPER_MAGIC)
{
mem_free(super);
errno = EROFS;
return -1;
}
// Parse the boot sector
fd->sectorSize = BYTES_PER_SECTOR;
fd->offset = 0;
fd->sectorCount = 0;
switch(ext2fs_le32_to_cpu(super->s_log_block_size))
{
case 1:
fd->sectorCount = (sec_t) ((u64) ext2fs_le32_to_cpu(super->s_blocks_count) * (u64) 2048 / (u64) BYTES_PER_SECTOR);
break;
case 2:
fd->sectorCount = (sec_t) ((u64) ext2fs_le32_to_cpu(super->s_blocks_count) * (u64) 4096 / (u64) BYTES_PER_SECTOR);
break;
case 3:
fd->sectorCount = (sec_t) ((u64) ext2fs_le32_to_cpu(super->s_blocks_count) * (u64) 8192 / (u64) BYTES_PER_SECTOR);
break;
default:
case 0:
fd->sectorCount = (sec_t) ((u64) ext2fs_le32_to_cpu(super->s_blocks_count) * (u64) 1024 / (u64) BYTES_PER_SECTOR);
break;
}
mem_free(super);
// Create the cache
fd->cache = _EXT2_cache_constructor(fd->cachePageCount, fd->cachePageSize, interface, fd->startSector + fd->sectorCount, fd->sectorSize);
return 0;
}
/**
* Flush data out and close volume
*/
static errcode_t device_gekko_io_close(io_channel dev)
{
// Get the device driver descriptor
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return -1;
}
if(!(dev->flags & EXT2_FLAG_RW))
return 0;
// Flush and destroy the cache (if required)
if (fd->cache) {
_EXT2_cache_flush(fd->cache);
_EXT2_cache_destructor(fd->cache);
}
return 0;
}
/**
*
*/
static s64 device_gekko_io_readbytes(io_channel dev, s64 offset, s64 count, void *buf)
{
ext2_log_trace("dev %p, offset %lli, count %lli\n", dev, offset, count);
// Get the device driver descriptor
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return -1;
}
// Get the device interface
const DISC_INTERFACE* interface = fd->interface;
if (!interface) {
errno = ENODEV;
return -1;
}
if(offset < 0)
{
errno = EROFS;
return -1;
}
if(!count)
return 0;
sec_t sec_start = (sec_t) fd->startSector;
sec_t sec_count = 1;
u32 buffer_offset = (u32) (offset % fd->sectorSize);
u8 *buffer = NULL;
// Determine the range of sectors required for this read
if (offset > 0) {
sec_start += (sec_t) floor((f64) offset / (f64) fd->sectorSize);
}
if (buffer_offset+count > fd->sectorSize) {
sec_count = (sec_t) ceil((f64) (buffer_offset+count) / (f64) fd->sectorSize);
}
// Don't read over the partitions limit
if(sec_start+sec_count > fd->startSector+fd->sectorCount)
{
ext2_log_trace("Error: read requested up to sector %lli while partition goes up to %lli\n", (s64) (sec_start+sec_count), (s64) (fd->startSector+fd->sectorCount));
errno = EROFS;
return -1;
}
// If this read happens to be on the sector boundaries then do the read straight into the destination buffer
if((buffer_offset == 0) && (count % fd->sectorSize == 0))
{
// Read from the device
ext2_log_trace("direct read from sector %d (%d sector(s) long)\n", sec_start, sec_count);
if (!device_gekko_io_readsectors(dev, sec_start, sec_count, buf))
{
ext2_log_trace("direct read failure @ sector %d (%d sector(s) long)\n", sec_start, sec_count);
errno = EIO;
return -1;
}
// Else read into a buffer and copy over only what was requested
}
else
{
// Allocate a buffer to hold the read data
buffer = (u8*)mem_alloc(sec_count * fd->sectorSize);
if (!buffer) {
errno = ENOMEM;
return -1;
}
// Read from the device
ext2_log_trace("buffered read from sector %d (%d sector(s) long)\n", sec_start, sec_count);
ext2_log_trace("count: %d sec_count:%d fd->sectorSize: %d )\n", (u32)count, (u32)sec_count,(u32)fd->sectorSize);
if (!device_gekko_io_readsectors(dev, sec_start, sec_count, buffer)) {
ext2_log_trace("buffered read failure @ sector %d (%d sector(s) long)\n", sec_start, sec_count);
mem_free(buffer);
errno = EIO;
return -1;
}
// Copy what was requested to the destination buffer
memcpy(buf, buffer + buffer_offset, count);
mem_free(buffer);
}
return count;
}
/**
*
*/
static s64 device_gekko_io_writebytes(io_channel dev, s64 offset, s64 count, const void *buf)
{
ext2_log_trace("dev %p, offset %lli, count %lli\n", dev, offset, count);
// Get the device driver descriptor
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return -1;
}
if(!(dev->flags & EXT2_FLAG_RW))
return -1;
// Get the device interface
const DISC_INTERFACE* interface = fd->interface;
if (!interface) {
errno = ENODEV;
return -1;
}
if(count < 0 || offset < 0) {
errno = EROFS;
return -1;
}
if(count == 0)
return 0;
sec_t sec_start = (sec_t) fd->startSector;
sec_t sec_count = 1;
u32 buffer_offset = (u32) (offset % fd->sectorSize);
u8 *buffer = NULL;
// Determine the range of sectors required for this write
if (offset > 0) {
sec_start += (sec_t) floor((f64) offset / (f64) fd->sectorSize);
}
if ((buffer_offset+count) > fd->sectorSize) {
sec_count = (sec_t) ceil((f64) (buffer_offset+count) / (f64) fd->sectorSize);
}
// Don't write over the partitions limit
if(sec_start+sec_count > fd->startSector+fd->sectorCount)
{
ext2_log_trace("Error: write requested up to sector %lli while partition goes up to %lli\n", (s64) (sec_start+sec_count), (s64) (fd->startSector+fd->sectorCount));
errno = EROFS;
return -1;
}
// If this write happens to be on the sector boundaries then do the write straight to disc
if((buffer_offset == 0) && (count % fd->sectorSize == 0))
{
// Write to the device
ext2_log_trace("direct write to sector %d (%d sector(s) long)\n", sec_start, sec_count);
if (!device_gekko_io_writesectors(dev, sec_start, sec_count, buf)) {
ext2_log_trace("direct write failure @ sector %d (%d sector(s) long)\n", sec_start, sec_count);
errno = EIO;
return -1;
}
// Else write from a buffer aligned to the sector boundaries
}
else
{
// Allocate a buffer to hold the write data
buffer = (u8 *) mem_alloc(sec_count * fd->sectorSize);
if (!buffer) {
errno = ENOMEM;
return -1;
}
// Read the first and last sectors of the buffer from disc (if required)
// NOTE: This is done because the data does not line up with the sector boundaries,
// we just read in the buffer edges where the data overlaps with the rest of the disc
if(buffer_offset != 0)
{
if (!device_gekko_io_readsectors(dev, sec_start, 1, buffer)) {
ext2_log_trace("read failure @ sector %d\n", sec_start);
mem_free(buffer);
errno = EIO;
return -1;
}
}
if((buffer_offset+count) % fd->sectorSize != 0)
{
if (!device_gekko_io_readsectors(dev, sec_start + sec_count - 1, 1, buffer + ((sec_count-1) * fd->sectorSize))) {
ext2_log_trace("read failure @ sector %d\n", sec_start + sec_count - 1);
mem_free(buffer);
errno = EIO;
return -1;
}
}
// Copy the data into the write buffer
memcpy(buffer + buffer_offset, buf, count);
// Write to the device
ext2_log_trace("buffered write to sector %d (%d sector(s) long)\n", sec_start, sec_count);
if (!device_gekko_io_writesectors(dev, sec_start, sec_count, buffer)) {
ext2_log_trace("buffered write failure @ sector %d\n", sec_start);
mem_free(buffer);
errno = EIO;
return -1;
}
// Free the buffer
mem_free(buffer);
}
return count;
}
/**
* Read function wrap for I/O manager
*/
static errcode_t device_gekko_io_read64(io_channel dev, unsigned long long block, int count, void *buf)
{
gekko_fd *fd = DEV_FD(dev);
s64 size = (count < 0) ? -count : count * dev->block_size;
fd->io_stats.bytes_read += size;
ext2_loff_t location = ((ext2_loff_t) block * dev->block_size) + fd->offset;
s64 read = device_gekko_io_readbytes(dev, location, size, buf);
if(read != size)
return EXT2_ET_SHORT_READ;
else if(read < 0)
return EXT2_ET_BLOCK_BITMAP_READ;
return EXT2_ET_OK;
}
static errcode_t device_gekko_io_read(io_channel dev, unsigned long block, int count, void *buf)
{
return device_gekko_io_read64(dev, block, count, buf);
}
/**
* Write function wrap for I/O manager
*/
static errcode_t device_gekko_io_write64(io_channel dev, unsigned long long block, int count, const void *buf)
{
gekko_fd *fd = DEV_FD(dev);
s64 size = (count < 0) ? -count : count * dev->block_size;
fd->io_stats.bytes_written += size;
ext2_loff_t location = ((ext2_loff_t) block * dev->block_size) + fd->offset;
s64 writen = device_gekko_io_writebytes(dev, location, size, buf);
if(writen != size)
return EXT2_ET_SHORT_WRITE;
else if(writen < 0)
return EXT2_ET_BLOCK_BITMAP_WRITE;
return EXT2_ET_OK;
}
static errcode_t device_gekko_io_write(io_channel dev, unsigned long block, int count, const void *buf)
{
return device_gekko_io_write64(dev, block, count, buf);
}
static bool device_gekko_io_readsectors(io_channel dev, sec_t sector, sec_t numSectors, void* buffer)
{
// Get the device driver descriptor
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return false;
}
// Read the sectors from disc (or cache, if enabled)
if (fd->cache)
return _EXT2_cache_readSectors(fd->cache, sector, numSectors, buffer);
else
return fd->interface->readSectors(sector, numSectors, buffer);
return false;
}
static bool device_gekko_io_writesectors(io_channel dev, sec_t sector, sec_t numSectors, const void* buffer)
{
// Get the device driver descriptor
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return false;
}
// Write the sectors to disc (or cache, if enabled)
if (fd->cache)
return _EXT2_cache_writeSectors(fd->cache, sector, numSectors, buffer);
else
return fd->interface->writeSectors(sector, numSectors, buffer);
return false;
}
/**
*
*/
static errcode_t device_gekko_io_sync(io_channel dev)
{
gekko_fd *fd = DEV_FD(dev);
ext2_log_trace("dev %p\n", dev);
// Check that the device can be written to
if(!(dev->flags & EXT2_FLAG_RW))
return -1;
// Flush any sectors in the disc cache (if required)
if (fd->cache) {
if (!_EXT2_cache_flush(fd->cache)) {
errno = EIO;
return EXT2_ET_BLOCK_BITMAP_WRITE;
}
}
return EXT2_ET_OK;
}
/**
*
*/
static errcode_t device_gekko_io_stat(io_channel dev, io_stats *stats)
{
EXT2_CHECK_MAGIC(dev, EXT2_ET_MAGIC_IO_CHANNEL);
gekko_fd *fd = DEV_FD(dev);
if (stats)
*stats = &fd->io_stats;
return EXT2_ET_OK;
}
static errcode_t device_gekko_set_blksize(io_channel dev, int blksize)
{
EXT2_CHECK_MAGIC(dev, EXT2_ET_MAGIC_IO_CHANNEL);
if (dev->block_size != blksize)
{
dev->block_size = blksize;
return device_gekko_io_sync(dev);
}
return EXT2_ET_OK;
}
/**
* Set options.
*/
static errcode_t device_gekko_set_option(io_channel dev, const char *option, const char *arg)
{
unsigned long long tmp;
char *end;
gekko_fd *fd = DEV_FD(dev);
if (!fd) {
errno = EBADF;
return -1;
}
EXT2_CHECK_MAGIC(dev, EXT2_ET_MAGIC_IO_CHANNEL);
if (!strcmp(option, "offset")) {
if (!arg)
return EXT2_ET_INVALID_ARGUMENT;
tmp = strtoull(arg, &end, 0);
if (*end)
return EXT2_ET_INVALID_ARGUMENT;
fd->offset = tmp;
if (fd->offset < 0)
return EXT2_ET_INVALID_ARGUMENT;
return 0;
}
return EXT2_ET_INVALID_ARGUMENT;
}
static errcode_t device_gekko_discard(io_channel channel, unsigned long long block, unsigned long long count)
{
//!TODO as soon as it is implemented in the official lib
return 0;
}
/**
* Device operations for working with gekko style devices and files.
*/
const struct struct_io_manager struct_gekko_io_manager =
{
EXT2_ET_MAGIC_IO_MANAGER,
"Wii/GC I/O Manager",
device_gekko_io_open,
device_gekko_io_close,
device_gekko_set_blksize,
device_gekko_io_read,
device_gekko_io_write,
device_gekko_io_sync,
0,
device_gekko_set_option,
device_gekko_io_stat,
device_gekko_io_read64,
device_gekko_io_write64,
device_gekko_discard,
};
io_manager gekko_io_manager = (io_manager) &struct_gekko_io_manager;