genode/repos/base-linux/src/core/stack_area.cc

121 lines
2.9 KiB
C++

/*
* \brief Linux-specific support code for the thread API
* \author Norman Feske
* \date 2010-01-13
*/
/*
* 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.
*/
/* Genode includes */
#include <rm_session/rm_session.h>
#include <ram_session/ram_session.h>
#include <base/printf.h>
#include <base/thread.h>
/* base-internal includes */
#include <base/internal/stack_area.h>
/**
* Region-manager session for allocating stacks
*
* This class corresponds to the managed dataspace that is normally used for
* organizing stacks within the stack. It "emulates" the sub address space by
* adjusting the local address argument to 'attach' with the offset of the
* stack area.
*/
class Stack_area_rm_session : public Genode::Rm_session
{
public:
Stack_area_rm_session()
{
flush_stack_area();
reserve_stack_area();
}
/**
* Attach backing store to stack area
*/
Local_addr attach(Genode::Dataspace_capability ds_cap,
Genode::size_t size, Genode::off_t offset,
bool use_local_addr, Local_addr local_addr,
bool executable)
{
using namespace Genode;
/* convert stack-area-relative to absolute virtual address */
addr_t addr = (addr_t)local_addr + stack_area_virtual_base();
/* use anonymous mmap for allocating stack backing store */
int flags = MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE;
int prot = PROT_READ | PROT_WRITE;
void *res = lx_mmap((void*)addr, size, prot, flags, -1, 0);
if ((addr_t)res != addr)
throw Region_conflict();
return local_addr;
}
void detach(Local_addr local_addr) {
PWRN("stack area detach from 0x%p - not implemented", (void *)local_addr); }
Genode::Pager_capability add_client(Genode::Thread_capability) {
return Genode::Pager_capability(); }
void remove_client(Genode::Pager_capability) { }
void fault_handler(Genode::Signal_context_capability) { }
State state() { return State(); }
Genode::Dataspace_capability dataspace() {
return Genode::Dataspace_capability(); }
};
class Stack_area_ram_session : public Genode::Ram_session
{
public:
Genode::Ram_dataspace_capability alloc(Genode::size_t size,
Genode::Cache_attribute) {
return Genode::Ram_dataspace_capability(); }
void free(Genode::Ram_dataspace_capability) { }
int ref_account(Genode::Ram_session_capability) { return 0; }
int transfer_quota(Genode::Ram_session_capability, Genode::size_t) { return 0; }
size_t quota() { return 0; }
size_t used() { return 0; }
};
/**
* Return single instance of the stack-area RM and RAM session
*/
namespace Genode {
Rm_session *env_stack_area_rm_session()
{
static Stack_area_rm_session inst;
return &inst;
}
Ram_session *env_stack_area_ram_session()
{
static Stack_area_ram_session inst;
return &inst;
}
}