153 lines
3.8 KiB
C++
153 lines
3.8 KiB
C++
/*
|
|
* \brief Provide a rom-file as block device (aka loop devices)
|
|
* \author Stefan Kalkowski
|
|
* \date 2010-07-07
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2010-2013 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU General Public License version 2.
|
|
*/
|
|
|
|
#include <base/exception.h>
|
|
#include <base/printf.h>
|
|
#include <os/config.h>
|
|
#include <cap_session/connection.h>
|
|
#include <rom_session/connection.h>
|
|
#include <block/component.h>
|
|
#include <block/driver.h>
|
|
|
|
using namespace Genode;
|
|
|
|
class Rom_blk : public Block::Driver
|
|
{
|
|
private:
|
|
|
|
Rom_connection _rom;
|
|
Dataspace_capability _file_cap; /* rom-file capability */
|
|
addr_t _file_addr; /* start address of attached file */
|
|
size_t _file_sz; /* file size */
|
|
size_t _blk_sz; /* block size */
|
|
size_t _blk_cnt; /* block count */
|
|
|
|
public:
|
|
|
|
Rom_blk(const char *name, size_t blk_sz)
|
|
: _rom(name),
|
|
_file_cap(_rom.dataspace()),
|
|
_file_addr(env()->rm_session()->attach(_file_cap)),
|
|
_file_sz(Dataspace_client(_file_cap).size()),
|
|
_blk_sz(blk_sz),
|
|
_blk_cnt(_file_sz/_blk_sz) { }
|
|
|
|
|
|
/****************************
|
|
** Block-driver interface **
|
|
****************************/
|
|
|
|
Genode::size_t block_size() { return _blk_sz; }
|
|
Genode::size_t block_count() { return _blk_cnt; }
|
|
|
|
Block::Session::Operations ops()
|
|
{
|
|
Block::Session::Operations o;
|
|
o.set_operation(Block::Packet_descriptor::READ);
|
|
return o;
|
|
}
|
|
|
|
void read(Genode::size_t block_number,
|
|
Genode::size_t block_count,
|
|
char *out_buffer)
|
|
{
|
|
/* sanity check block number */
|
|
if ((block_number + block_count > _file_sz / _blk_sz)
|
|
|| block_number < 0) {
|
|
PWRN("requested blocks %zd-%zd out of range!",
|
|
block_number, block_number + block_count);
|
|
return;
|
|
}
|
|
|
|
size_t offset = block_number * _blk_sz;
|
|
size_t size = block_count * _blk_sz;
|
|
|
|
/* copy file content to packet payload */
|
|
memcpy(out_buffer, (void*)(_file_addr + offset), size);
|
|
}
|
|
|
|
void write(Genode::size_t block_number,
|
|
Genode::size_t block_count,
|
|
char const *buffer)
|
|
{
|
|
PWRN("write attempt on read-only device");
|
|
}
|
|
|
|
/*
|
|
* This driver does not support DMA operation, currently.
|
|
*/
|
|
|
|
void read_dma(Genode::size_t, Genode::size_t, Genode::addr_t) {
|
|
throw Io_error(); }
|
|
|
|
void write_dma(Genode::size_t, Genode::size_t, Genode::addr_t) {
|
|
throw Io_error(); }
|
|
|
|
bool dma_enabled() { return false; }
|
|
|
|
Genode::Ram_dataspace_capability alloc_dma_buffer(Genode::size_t size) {
|
|
return Genode::env()->ram_session()->alloc(size, false); }
|
|
|
|
void sync() {}
|
|
};
|
|
|
|
|
|
struct Factory : Block::Driver_factory
|
|
{
|
|
Block::Driver *create()
|
|
{
|
|
char file[64];
|
|
size_t blk_sz = 512;
|
|
|
|
try {
|
|
config()->xml_node().attribute("file").value(file, sizeof(file));
|
|
config()->xml_node().attribute("block_size").value(&blk_sz);
|
|
}
|
|
catch (...) { }
|
|
|
|
PINF("Using file=%s as device with block size %zx.", file, blk_sz);
|
|
|
|
try {
|
|
Rom_blk *driver = new (Genode::env()->heap()) Rom_blk(file, blk_sz);
|
|
return driver;
|
|
} catch(Rom_connection::Rom_connection_failed) {
|
|
PERR("Cannot open file %s.", file);
|
|
}
|
|
throw Root::Unavailable();
|
|
}
|
|
|
|
void destroy(Block::Driver *driver) {
|
|
Genode::destroy(env()->heap(), driver); }
|
|
};
|
|
|
|
|
|
int main()
|
|
{
|
|
enum { STACK_SIZE = 8192 };
|
|
static Cap_connection cap;
|
|
static Rpc_entrypoint ep(&cap, STACK_SIZE, "rom_blk_ep");
|
|
|
|
static Signal_receiver receiver;
|
|
static Factory driver_factory;
|
|
static Block::Root block_root(&ep, env()->heap(), driver_factory, receiver);
|
|
|
|
env()->parent()->announce(ep.manage(&block_root));
|
|
|
|
while (true) {
|
|
Signal s = receiver.wait_for_signal();
|
|
static_cast<Signal_dispatcher_base *>(s.context())->dispatch(s.num());
|
|
}
|
|
|
|
return 0;
|
|
}
|