genode/repos/base-sel4/src/core/include/ipc_pager.h

168 lines
3.8 KiB
C++

/*
* \brief Pager support for Genode on seL4
* \author Norman Feske
* \date 2014-10-14
*/
/*
* Copyright (C) 2014-2017 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 _CORE__INCLUDE__IPC_PAGER_H_
#define _CORE__INCLUDE__IPC_PAGER_H_
#include <base/cache.h>
#include <base/ipc.h>
#include <base/stdint.h>
namespace Genode {
class Mapping;
class Ipc_pager;
}
class Genode::Mapping
{
friend class Ipc_pager;
private:
addr_t _from_phys_addr { 0 };
addr_t _to_virt_addr { 0 };
Cache_attribute _attr { CACHED };
size_t _num_pages { 0 };
addr_t _fault_type { 0 };
bool _writeable { false };
bool _executable { false };
enum { PAGE_SIZE_LOG2 = 12 };
public:
/**
* Constructor
*/
Mapping(addr_t dst_addr, addr_t src_addr,
Cache_attribute const cacheability, bool,
unsigned l2size, bool rw, bool executable)
:
_from_phys_addr(src_addr),
_to_virt_addr(dst_addr),
_attr(cacheability),
_num_pages(1 << (l2size - PAGE_SIZE_LOG2)),
_writeable(rw), _executable(executable)
{ }
/**
* Construct invalid mapping
*/
Mapping() { }
/**
* Prepare map operation
*
* No preparations are needed on seL4 because all mapping
* originate from the physical address space.
*/
void prepare_map_operation() { }
addr_t from_phys() const { return _from_phys_addr; }
addr_t to_virt() const { return _to_virt_addr; }
size_t num_pages() const { return _num_pages; }
bool writeable() const { return _writeable; }
bool executable() const { return _executable; }
Cache_attribute cacheability() const { return _attr; }
addr_t fault_type() const { return _fault_type; }
};
/**
* Special paging server class
*/
class Genode::Ipc_pager : public Native_capability
{
private:
addr_t _badge = 0; /* faulted badge of thread */
addr_t _reply_sel = 0; /* selector to save reply cap */
addr_t _pf_addr = 0; /* page-fault address */
addr_t _pf_ip = 0; /* instruction pointer of faulter */
addr_t _fault_type = 0; /* type of fault */
bool _pf_write = false; /* true on write fault */
bool _pf_exec = false; /* true on exec fault */
bool _pf_align = false; /* true on unaligned fault */
Mapping _reply_mapping { };
public:
/**
* Constructor
*/
Ipc_pager();
/**
* Wait for a new page fault received as short message IPC
*/
void wait_for_fault();
/**
* Reply current page-fault and wait for a new one
*/
void reply_and_wait_for_fault();
/**
* Request instruction pointer of current page fault
*/
addr_t fault_ip() { return _pf_ip; }
/**
* Request fault address of current page fault
*/
addr_t fault_addr() { return _pf_addr; }
/**
* Set parameters for next reply
*/
void set_reply_mapping(Mapping m)
{
_reply_mapping = m;
_reply_mapping._fault_type = _fault_type;
}
/**
* Set destination for next reply
*/
void reply_save_caller(addr_t sel) { _reply_sel = sel; }
/**
* Return badge for faulting thread
*/
unsigned long badge() const { return _badge; }
/**
* Return true if page fault was a write fault
*/
bool write_fault() const { return _pf_write; }
/**
* Return true if page fault was on non-executable memory
*/
bool exec_fault() const { return _pf_exec; }
/**
* Return true if page fault was due to unaligned memory access
*/
bool align_fault() const { return _pf_align; }
/**
* Install memory mapping after pager code executed.
*/
bool install_mapping();
};
#endif /* _CORE__INCLUDE__IPC_PAGER_H_ */