genode/repos/base-nova/src/core/ram_session_support.cc
Norman Feske 17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00

99 lines
2.8 KiB
C++

/*
* \brief Export RAM dataspace as shared memory object
* \author Norman Feske
* \date 2009-10-02
*/
/*
* Copyright (C) 2009-2015 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 <base/thread.h>
/* core includes */
#include <ram_session_component.h>
#include <platform.h>
#include <util.h>
#include <nova_util.h>
/* NOVA includes */
#include <nova/syscalls.h>
using namespace Genode;
void Ram_session_component::_revoke_ram_ds(Dataspace_component *ds) { }
static inline void * alloc_region(Dataspace_component *ds, const size_t size)
{
/*
* Allocate range in core's virtual address space
*
* Start with trying to use natural alignment. If this does not work,
* successively weaken the alignment constraint until we hit the page size.
*/
void *virt_addr = 0;
size_t align_log2 = log2(ds->size());
for (; align_log2 >= get_page_size_log2(); align_log2--) {
if (platform()->region_alloc()->alloc_aligned(size,
&virt_addr, align_log2).ok())
break;
}
return virt_addr;
}
void Ram_session_component::_clear_ds(Dataspace_component *ds)
{
size_t page_rounded_size = align_addr(ds->size(), get_page_size_log2());
size_t memset_count = page_rounded_size / 4;
addr_t memset_ptr = ds->core_local_addr();
if ((memset_count * 4 == page_rounded_size) && !(memset_ptr & 0x3))
asm volatile ("rep stosl" : "+D" (memset_ptr), "+c" (memset_count)
: "a" (0) : "memory");
else
memset(reinterpret_cast<void *>(memset_ptr), 0, page_rounded_size);
/* we don't keep any core-local mapping */
unmap_local(reinterpret_cast<Nova::Utcb *>(Thread::myself()->utcb()),
ds->core_local_addr(),
page_rounded_size >> get_page_size_log2());
platform()->region_alloc()->free((void*)ds->core_local_addr(),
page_rounded_size);
ds->assign_core_local_addr(nullptr);
}
void Ram_session_component::_export_ram_ds(Dataspace_component *ds) {
size_t page_rounded_size = align_addr(ds->size(), get_page_size_log2());
/* allocate the virtual region contiguous for the dataspace */
void * virt_ptr = alloc_region(ds, page_rounded_size);
if (!virt_ptr)
throw Out_of_metadata();
/* map it writeable for _clear_ds */
Nova::Utcb * const utcb = reinterpret_cast<Nova::Utcb *>(Thread::myself()->utcb());
const Nova::Rights rights_rw(true, true, false);
if (map_local(utcb, ds->phys_addr(), reinterpret_cast<addr_t>(virt_ptr),
page_rounded_size >> get_page_size_log2(), rights_rw, true)) {
platform()->region_alloc()->free(virt_ptr, page_rounded_size);
throw Out_of_metadata();
}
/* assign virtual address to the dataspace to be used by clear_ds */
ds->assign_core_local_addr(virt_ptr);
}