genode/repos/base/include/base/attached_io_mem_dataspace.h
Norman Feske 4d442bca30 Streamline exception types
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.

Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.

This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
2017-05-31 13:16:07 +02:00

108 lines
2.9 KiB
C++

/*
* \brief I/O MEM dataspace utility
* \author Norman Feske
* \date 2011-05-19
*/
/*
* Copyright (C) 2011-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _INCLUDE__BASE__ATTACHED_IO_MEM_DATASPACE_H_
#define _INCLUDE__BASE__ATTACHED_IO_MEM_DATASPACE_H_
#include <io_mem_session/connection.h>
#include <base/env.h>
namespace Genode { class Attached_io_mem_dataspace; }
/**
* Request and locally attach a memory-mapped I/O resource
*
* This class is a wrapper for a typical sequence of operations performed
* by device drivers to access memory-mapped device resources. Its sole
* purpose is to avoid duplicated code.
*/
class Genode::Attached_io_mem_dataspace
{
private:
Region_map &_env_rm;
Io_mem_connection _mmio;
Io_mem_dataspace_capability _ds;
void *_local_addr;
public:
/**
* Constructor
*
* \param base base address of memory-mapped I/O resource
* \param size size of resource
* \param write_combined enable write combining for the resource
*
* \throw Service_denied
* \throw Insufficient_ram_quota
* \throw Insufficient_cap_quota
* \throw Out_of_ram
* \throw Out_of_caps
* \throw Region_map::Region_conflict
* \throw Region_map::Invalid_dataspace
*/
Attached_io_mem_dataspace(Env &env, Genode::addr_t base, Genode::size_t size,
bool write_combined = false)
:
_env_rm(env.rm()),
_mmio(env, base, size, write_combined),
_ds(_mmio.dataspace()),
_local_addr(env.rm().attach(_ds))
{
/* apply sub-page offset to virtual address */
_local_addr = (void *)((addr_t)_local_addr | (base & (addr_t)0xfff));
}
/**
* Constructor
*
* \noapi
* \deprecated Use the constructor with 'Env &' as first
* argument instead
*/
Attached_io_mem_dataspace(Genode::addr_t base, Genode::size_t size,
bool write_combined = false) __attribute__((deprecated))
:
_env_rm(*env_deprecated()->rm_session()),
_mmio(false, base, size, write_combined),
_ds(_mmio.dataspace()),
_local_addr(_env_rm.attach(_ds))
{
/* apply sub-page offset to virtual address */
_local_addr = (void *)((addr_t)_local_addr | (base & (addr_t)0xfff));
}
/**
* Destructor
*/
~Attached_io_mem_dataspace() { _env_rm.detach(_local_addr); }
/**
* Return capability of the used RAM dataspace
*/
Io_mem_dataspace_capability cap() { return _ds; }
/**
* Request local address
*
* This is a template to avoid inconvenient casts at the caller.
* A newly allocated I/O MEM dataspace is untyped memory anyway.
*/
template <typename T>
T *local_addr() { return static_cast<T *>(_local_addr); }
};
#endif /* _INCLUDE__BASE__ATTACHED_IO_MEM_DATASPACE_H_ */