OpenSolaris_b135/uts/i86pc/vm/hat_kdi.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* HAT interfaces used by the kernel debugger to interact with the VM system.
* These interfaces are invoked when the world is stopped. As such, no blocking
* operations may be performed.
*/
#include <sys/cpuvar.h>
#include <sys/kdi_impl.h>
#include <sys/errno.h>
#include <sys/systm.h>
#include <sys/sysmacros.h>
#include <sys/mman.h>
#include <sys/bootconf.h>
#include <sys/cmn_err.h>
#include <vm/seg_kmem.h>
#include <vm/hat_i86.h>
#if defined(__xpv)
#include <sys/hypervisor.h>
#endif
#include <sys/bootinfo.h>
#include <vm/kboot_mmu.h>
#include <sys/machsystm.h>
/*
* The debugger needs direct access to the PTE of one page table entry
* in order to implement vtop and physical read/writes
*/
static uintptr_t hat_kdi_page = 0; /* vaddr for phsical page accesses */
static uint_t use_kbm = 1;
uint_t hat_kdi_use_pae; /* if 0, use x86pte32_t for pte type */
#if !defined(__xpv)
static x86pte_t *hat_kdi_pte = NULL; /* vaddr of pte for hat_kdi_page */
#endif
/*
* Get the address for remapping physical pages during boot
*/
void
hat_boot_kdi_init(void)
{
hat_kdi_page = (uintptr_t)kbm_push(0); /* first call gets address... */
}
/*
* Switch to using a page in the kernel's va range for physical memory access.
* We need to allocate a virtual page, then permanently map in the page that
* contains the PTE to it.
*/
void
hat_kdi_init(void)
{
/*LINTED:set but not used in function*/
htable_t *ht;
/*
* Get an kernel page VA to use for phys mem access. Then make sure
* the VA has a page table.
*/
hat_kdi_use_pae = mmu.pae_hat;
hat_kdi_page = (uintptr_t)vmem_alloc(heap_arena, PAGESIZE, VM_SLEEP);
ht = htable_create(kas.a_hat, hat_kdi_page, 0, NULL);
use_kbm = 0;
#ifndef __xpv
/*
* Get an address at which to put the pagetable and devload it.
*/
hat_kdi_pte = vmem_xalloc(heap_arena, MMU_PAGESIZE, MMU_PAGESIZE, 0,
0, NULL, NULL, VM_SLEEP);
hat_devload(kas.a_hat, (caddr_t)hat_kdi_pte, MMU_PAGESIZE, ht->ht_pfn,
PROT_READ | PROT_WRITE | HAT_NOSYNC | HAT_UNORDERED_OK,
HAT_LOAD | HAT_LOAD_NOCONSIST);
hat_kdi_pte =
PT_INDEX_PTR(hat_kdi_pte, htable_va2entry(hat_kdi_page, ht));
HTABLE_INC(ht->ht_valid_cnt);
htable_release(ht);
#endif
}
#ifdef __xpv
/*
* translate machine address to physical address
*/
static uint64_t
kdi_ptom(uint64_t pa)
{
extern pfn_t *mfn_list;
ulong_t mfn = mfn_list[mmu_btop(pa)];
return (pfn_to_pa(mfn) | (pa & MMU_PAGEOFFSET));
}
/*
* This is like mfn_to_pfn(), but we can't use ontrap() from kmdb.
* Instead we let the fault happen and kmdb deals with it.
*/
static uint64_t
kdi_mtop(uint64_t ma)
{
pfn_t pfn;
mfn_t mfn = ma >> MMU_PAGESHIFT;
if (HYPERVISOR_memory_op(XENMEM_maximum_ram_page, NULL) < mfn)
return (ma | PFN_IS_FOREIGN_MFN);
pfn = mfn_to_pfn_mapping[mfn];
if (pfn >= mfn_count || pfn_to_mfn(pfn) != mfn)
return (ma | PFN_IS_FOREIGN_MFN);
return (pfn_to_pa(pfn) | (ma & MMU_PAGEOFFSET));
}
#else
#define kdi_mtop(m) (m)
#define kdi_ptom(p) (p)
#endif
/*ARGSUSED*/
int
kdi_vtop(uintptr_t va, uint64_t *pap)
{
uintptr_t vaddr = va;
size_t len;
pfn_t pfn;
uint_t prot;
int level;
x86pte_t pte;
int index;
/*
* if the mmu struct isn't relevant yet, we need to probe
* the boot loader's pagetables.
*/
if (!khat_running) {
if (kbm_probe(&vaddr, &len, &pfn, &prot) == 0)
return (ENOENT);
if (vaddr > va)
return (ENOENT);
if (vaddr < va)
pfn += mmu_btop(va - vaddr);
*pap = pfn_to_pa(pfn) + (vaddr & MMU_PAGEOFFSET);
return (0);
}
/*
* We can't go through normal hat routines, so we'll use
* kdi_pread() to walk the page tables
*/
#if defined(__xpv)
*pap = pfn_to_pa(CPU->cpu_current_hat->hat_htable->ht_pfn);
#else
*pap = getcr3() & MMU_PAGEMASK;
#endif
for (level = mmu.max_level; ; --level) {
index = (va >> LEVEL_SHIFT(level)) & (mmu.ptes_per_table - 1);
*pap += index << mmu.pte_size_shift;
pte = 0;
if (kdi_pread((caddr_t)&pte, mmu.pte_size, *pap, &len) != 0)
return (ENOENT);
if (pte == 0)
return (ENOENT);
if (level > 0 && level <= mmu.max_page_level &&
(pte & PT_PAGESIZE)) {
*pap = kdi_mtop(pte & PT_PADDR_LGPG);
break;
} else {
*pap = kdi_mtop(pte & PT_PADDR);
if (level == 0)
break;
}
}
*pap += va & LEVEL_OFFSET(level);
return (0);
}
static int
kdi_prw(caddr_t buf, size_t nbytes, uint64_t pa, size_t *ncopiedp, int doread)
{
size_t ncopied = 0;
off_t pgoff;
size_t sz;
caddr_t va;
caddr_t from;
caddr_t to;
x86pte_t pte;
/*
* if this is called before any initialization - fail
*/
if (hat_kdi_page == 0)
return (EAGAIN);
while (nbytes > 0) {
/*
* figure out the addresses and construct a minimal PTE
*/
pgoff = pa & MMU_PAGEOFFSET;
sz = MIN(nbytes, MMU_PAGESIZE - pgoff);
va = (caddr_t)hat_kdi_page + pgoff;
pte = kdi_ptom(mmu_ptob(mmu_btop(pa))) | PT_VALID;
if (doread) {
from = va;
to = buf;
} else {
PTE_SET(pte, PT_WRITABLE);
from = buf;
to = va;
}
/*
* map the physical page
*/
if (use_kbm)
(void) kbm_push(pa);
#if defined(__xpv)
else
(void) HYPERVISOR_update_va_mapping(
(uintptr_t)va, pte, UVMF_INVLPG);
#else
else if (hat_kdi_use_pae)
*hat_kdi_pte = pte;
else
*(x86pte32_t *)hat_kdi_pte = pte;
mmu_tlbflush_entry((caddr_t)hat_kdi_page);
#endif
bcopy(from, to, sz);
/*
* erase the mapping
*/
if (use_kbm)
kbm_pop();
#if defined(__xpv)
else
(void) HYPERVISOR_update_va_mapping(
(uintptr_t)va, 0, UVMF_INVLPG);
#else
else if (hat_kdi_use_pae)
*hat_kdi_pte = 0;
else
*(x86pte32_t *)hat_kdi_pte = 0;
mmu_tlbflush_entry((caddr_t)hat_kdi_page);
#endif
buf += sz;
pa += sz;
nbytes -= sz;
ncopied += sz;
}
if (ncopied == 0)
return (ENOENT);
*ncopiedp = ncopied;
return (0);
}
int
kdi_pread(caddr_t buf, size_t nbytes, uint64_t addr, size_t *ncopiedp)
{
return (kdi_prw(buf, nbytes, addr, ncopiedp, 1));
}
int
kdi_pwrite(caddr_t buf, size_t nbytes, uint64_t addr, size_t *ncopiedp)
{
return (kdi_prw(buf, nbytes, addr, ncopiedp, 0));
}
/*
* Return the number of bytes, relative to the beginning of a given range, that
* are non-toxic (can be read from and written to with relative impunity).
*/
/*ARGSUSED*/
size_t
kdi_range_is_nontoxic(uintptr_t va, size_t sz, int write)
{
#if defined(__amd64)
extern uintptr_t toxic_addr;
extern size_t toxic_size;
/*
* Check 64 bit toxic range.
*/
if (toxic_addr != 0 &&
va + sz >= toxic_addr &&
va < toxic_addr + toxic_size)
return (va < toxic_addr ? toxic_addr - va : 0);
/*
* avoid any Virtual Address hole
*/
if (va + sz >= hole_start && va < hole_end)
return (va < hole_start ? hole_start - va : 0);
return (sz);
#elif defined(__i386)
extern void *device_arena_contains(void *, size_t, size_t *);
uintptr_t v;
v = (uintptr_t)device_arena_contains((void *)va, sz, NULL);
if (v == 0)
return (sz);
else if (v <= va)
return (0);
else
return (v - va);
#endif /* __i386 */
}