genode/base-nova/src/core/include/nova_util.h

234 lines
6.8 KiB
C++

/*
* \brief NOVA-specific convenience functions
* \author Norman Feske
* \author Sebastian Sumpf
* \author Alexander Boettcher
* \date 2010-01-19
*/
/*
* 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.
*/
#ifndef _NOVA_UTIL_H_
#define _NOVA_UTIL_H_
/* Genode includes */
#include <base/printf.h>
/* NOVA includes */
#include <nova/syscalls.h>
/* local includes */
#include <echo.h>
#include <util.h>
enum { verbose_local_map = false };
/**
* Return boot CPU number. It is required if threads in core should be placed
* on the same CPU as the main thread.
*/
inline Genode::addr_t boot_cpu()
{
/**
* Initial value of ax and di register, saved by the crt0 startup code
* and SOLELY VALID in 'core' !!!
*
* For x86_32 - __initial_ax contains the number of the boot CPU.
* For x86_64 - __initial_di contains the number of the boot CPU.
*/
extern Genode::addr_t __initial_ax;
extern Genode::addr_t __initial_di;
return (sizeof(void *) > 4) ? __initial_di : __initial_ax;
}
/**
* Establish a mapping
*
* \param utcb UTCB of the calling EC
* \param src_crd capability range descriptor of source
* resource to map locally
* \param dst_crd capability range descriptor of mapping
* target
* \param kern_pd Whether to map the items from the kernel or from core
* \param dma_mem Whether the memory is usable for DMA or not
*
* This functions sends a message from the calling EC to the echo EC.
* The calling EC opens a receive window and the echo EC creates a transfer
* item of the message and replies. The kernel will map during the reply
* from the echo EC to the calling EC.
*/
static int map_local(Nova::Utcb *utcb, Nova::Crd src_crd, Nova::Crd dst_crd,
bool kern_pd = false, bool dma_mem = false)
{
/* open receive window at current EC */
utcb->crd_rcv = dst_crd;
/* tell echo thread what to map */
utcb->msg[0] = src_crd.value();
utcb->msg[1] = 0;
utcb->msg[2] = kern_pd;
utcb->msg[3] = dma_mem;
utcb->set_msg_word(4);
/* establish the mapping via a portal traversal during reply phase */
Nova::uint8_t res = Nova::call(echo()->pt_sel());
if (res != Nova::NOVA_OK || utcb->msg_words() != 1 || !utcb->msg[0] ||
utcb->msg_items() != 1) {
PERR("Failure - map_local 0x%lx:%lu:%u->0x%lx:%lu:%u - call result=%x"
" utcb=%x:%x:%lx !!! utcb=%p kern=%u",
src_crd.addr(), src_crd.order(), src_crd.type(),
dst_crd.addr(), dst_crd.order(), dst_crd.type(), res,
utcb->msg_items(), utcb->msg_words(), utcb->msg[0], utcb, kern_pd);
return res > 0 ? res : -1;
}
/* clear receive window */
utcb->crd_rcv = 0;
return 0;
}
static inline int unmap_local(Nova::Crd crd, bool self = true) {
return Nova::revoke(crd, self); }
inline int map_local_phys_to_virt(Nova::Utcb *utcb, Nova::Crd src,
Nova::Crd dst) {
return map_local(utcb, src, dst, true); }
inline int map_local_one_to_one(Nova::Utcb *utcb, Nova::Crd crd) {
return map_local(utcb, crd, crd, true); }
/**
* Find least significant set bit in value
*/
inline unsigned char
lsb_bit(unsigned long const &value, unsigned char const shift = 0)
{
unsigned long const scan = value >> shift;
if (scan == 0) return 0;
unsigned char pos = __builtin_ctzl(scan);
unsigned char res = shift ? pos + shift : pos;
return res;
}
/**
* Remap pages in the local address space
*
* \param utcb UTCB of the main thread
* \param from_start physical source address
* \param to_start local virtual destination address
* \param num_pages number of pages to map
*/
inline int map_local(Nova::Utcb *utcb,
Genode::addr_t from_start, Genode::addr_t to_start,
Genode::size_t num_pages,
Nova::Rights const &permission,
bool kern_pd = false, bool dma_mem = false)
{
if (verbose_local_map)
Genode::printf("::map_local: from %lx to %lx, %zd pages from kernel %u\n",
from_start, to_start, num_pages, kern_pd);
using namespace Nova;
using namespace Genode;
size_t const size = num_pages << get_page_size_log2();
addr_t const from_end = from_start + size;
addr_t const to_end = to_start + size;
for (addr_t offset = 0; offset < size; ) {
addr_t const from_curr = from_start + offset;
addr_t const to_curr = to_start + offset;
/*
* The common alignment corresponds to the number of least significant
* zero bits in both addresses.
*/
addr_t const common_bits = from_curr | to_curr;
/* find least set bit in common bits */
size_t order = lsb_bit(common_bits, get_page_size_log2());
/* look if flexpage fits into both 'from' and 'to' address range */
if ((from_end - from_curr) < (1UL << order))
order = log2(from_end - from_curr);
if ((to_end - to_curr) < (1UL << order))
order = log2(to_end - to_curr);
if (verbose_local_map)
Genode::printf("::map_local: order %zx %lx:%lx %lx:%lx\n",
order, from_curr, from_end, to_curr, to_end);
int const res = map_local(utcb,
Mem_crd((from_curr >> 12), order - get_page_size_log2(), permission),
Mem_crd((to_curr >> 12), order - get_page_size_log2(), permission),
kern_pd, dma_mem);
if (res) return res;
/* advance offset by current flexpage size */
offset += (1UL << order);
}
return 0;
}
/**
* Unmap pages from the local address space
*
* \param utcb UTCB of the main thread
* \param start local virtual address
* \param num_pages number of pages to unmap
* \param self unmap from this pd or solely from other pds
* \param self map from this pd or solely from other pds
* \param rights rights to be revoked, default: all rwx
*/
inline void unmap_local(Nova::Utcb *utcb, Genode::addr_t start,
Genode::size_t num_pages,
bool const self = true,
Nova::Rights const rwx = Nova::Rights(true, true, true))
{
using namespace Nova;
using namespace Genode;
Genode::addr_t base = start >> get_page_size_log2();
if (start & (get_page_size() - 1)) {
PERR("unmap failed - unaligned address specified");
return;
}
if (verbose_local_map)
PINF("Unmapping local: range 0x%lx+0x%zx", base, num_pages);
while (num_pages) {
unsigned char const base_bit = lsb_bit(base);
unsigned char const order_bit = min(log2(num_pages), 31U);
unsigned char const order = min(order_bit, base_bit);
Mem_crd const crd(base, order, rwx);
if (verbose_local_map)
PINF("Unmapping local: 0x%lx+0x%lx", crd.base(),
1UL << crd.order());
unmap_local(crd, self);
num_pages -= 1UL << order;
base += 1UL << order;
}
}
#endif /* _NOVA_UTIL_H_ */