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pmap.c
3385 lines (2848 loc) · 81.1 KB
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pmap.c
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/* $OpenBSD: pmap.c,v 1.148 2021/09/14 16:14:50 kettenis Exp $ */
/* $NetBSD: pmap.c,v 1.3 2003/05/08 18:13:13 thorpej Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright 2001 (c) Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Frank van der Linden for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This is the i386 pmap modified and generalized to support x86-64
* as well. The idea is to hide the upper N levels of the page tables
* inside pmap_get_ptp, pmap_free_ptp and pmap_growkernel. The rest
* is mostly untouched, except that it uses some more generalized
* macros and interfaces.
*
* This pmap has been tested on the i386 as well, and it can be easily
* adapted to PAE.
*
* fvdl@wasabisystems.com 18-Jun-2001
*/
/*
* pmap.c: i386 pmap module rewrite
* Chuck Cranor <chuck@ccrc.wustl.edu>
* 11-Aug-97
*
* history of this pmap module: in addition to my own input, i used
* the following references for this rewrite of the i386 pmap:
*
* [1] the NetBSD i386 pmap. this pmap appears to be based on the
* BSD hp300 pmap done by Mike Hibler at University of Utah.
* it was then ported to the i386 by William Jolitz of UUNET
* Technologies, Inc. Then Charles M. Hannum of the NetBSD
* project fixed some bugs and provided some speed ups.
*
* [2] the FreeBSD i386 pmap. this pmap seems to be the
* Hibler/Jolitz pmap, as modified for FreeBSD by John S. Dyson
* and David Greenman.
*
* [3] the Mach pmap. this pmap, from CMU, seems to have migrated
* between several processors. the VAX version was done by
* Avadis Tevanian, Jr., and Michael Wayne Young. the i386
* version was done by Lance Berc, Mike Kupfer, Bob Baron,
* David Golub, and Richard Draves. the alpha version was
* done by Alessandro Forin (CMU/Mach) and Chris Demetriou
* (NetBSD/alpha).
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/atomic.h>
#include <sys/proc.h>
#include <sys/pool.h>
#include <sys/user.h>
#include <sys/mutex.h>
#include <uvm/uvm.h>
#include <machine/cpu.h>
#ifdef MULTIPROCESSOR
#include <machine/i82489reg.h>
#include <machine/i82489var.h>
#endif
#include "vmm.h"
#if NVMM > 0
#include <machine/vmmvar.h>
#endif /* NVMM > 0 */
#include "acpi.h"
/* #define PMAP_DEBUG */
#ifdef PMAP_DEBUG
#define DPRINTF(x...) do { printf(x); } while(0)
#else
#define DPRINTF(x...)
#endif /* PMAP_DEBUG */
/*
* general info:
*
* - for an explanation of how the i386 MMU hardware works see
* the comments in <machine/pte.h>.
*
* - for an explanation of the general memory structure used by
* this pmap (including the recursive mapping), see the comments
* in <machine/pmap.h>.
*
* this file contains the code for the "pmap module." the module's
* job is to manage the hardware's virtual to physical address mappings.
* note that there are two levels of mapping in the VM system:
*
* [1] the upper layer of the VM system uses vm_map's and vm_map_entry's
* to map ranges of virtual address space to objects/files. for
* example, the vm_map may say: "map VA 0x1000 to 0x22000 read-only
* to the file /bin/ls starting at offset zero." note that
* the upper layer mapping is not concerned with how individual
* vm_pages are mapped.
*
* [2] the lower layer of the VM system (the pmap) maintains the mappings
* from virtual addresses. it is concerned with which vm_page is
* mapped where. for example, when you run /bin/ls and start
* at page 0x1000 the fault routine may lookup the correct page
* of the /bin/ls file and then ask the pmap layer to establish
* a mapping for it.
*
* note that information in the lower layer of the VM system can be
* thrown away since it can easily be reconstructed from the info
* in the upper layer.
*
* data structures we use include:
* - struct pmap: describes the address space of one process
* - struct pv_entry: describes one <PMAP,VA> mapping of a PA
* - struct pg_to_free: a list of virtual addresses whose mappings
* have been changed. used for TLB flushing.
*/
/*
* memory allocation
*
* - there are three data structures that we must dynamically allocate:
*
* [A] new process' page directory page (PDP)
* - plan 1: done at pmap_create() we use
* pool_get(&pmap_pmap_pool, PR_WAITOK) to do this allocation.
*
* if we are low in free physical memory then we sleep in
* pool_get() -- in this case this is ok since we are creating
* a new pmap and should not be holding any locks.
*
* XXX: the fork code currently has no way to return an "out of
* memory, try again" error code since uvm_fork [fka vm_fork]
* is a void function.
*
* [B] new page tables pages (PTP)
* call uvm_pagealloc()
* => success: zero page, add to pm_pdir
* => failure: we are out of free vm_pages, let pmap_enter()
* tell UVM about it.
*
* note: for kernel PTPs, we start with NKPTP of them. as we map
* kernel memory (at uvm_map time) we check to see if we've grown
* the kernel pmap. if so, we call the optional function
* pmap_growkernel() to grow the kernel PTPs in advance.
*
* [C] pv_entry structures
* - try to allocate one from the pool.
* If we fail, we simply let pmap_enter() tell UVM about it.
*/
long nkptp[] = NKPTP_INITIALIZER;
const vaddr_t ptp_masks[] = PTP_MASK_INITIALIZER;
const int ptp_shifts[] = PTP_SHIFT_INITIALIZER;
const long nkptpmax[] = NKPTPMAX_INITIALIZER;
const long nbpd[] = NBPD_INITIALIZER;
pd_entry_t *const normal_pdes[] = PDES_INITIALIZER;
#define pmap_pte_set(p, n) atomic_swap_64(p, n)
#define pmap_pte_clearbits(p, b) x86_atomic_clearbits_u64(p, b)
#define pmap_pte_setbits(p, b) x86_atomic_setbits_u64(p, b)
/*
* global data structures
*/
struct pmap kernel_pmap_store; /* the kernel's pmap (proc0) */
/*
* pmap_pg_wc: if our processor supports PAT then we set this
* to be the pte bits for Write Combining. Else we fall back to
* UC- so mtrrs can override the cacheability;
*/
int pmap_pg_wc = PG_UCMINUS;
/*
* pmap_use_pcid: nonzero if PCID use is enabled (currently we require INVPCID)
*
* The next three are zero unless and until PCID support is enabled so code
* can just 'or' them in as needed without tests.
* cr3_pcid: CR3_REUSE_PCID
* cr3_pcid_proc and cr3_pcid_temp: PCID_PROC and PCID_TEMP
*/
#if PCID_KERN != 0
# error "pmap.c assumes PCID_KERN is zero"
#endif
int pmap_use_pcid;
static u_int cr3_pcid_proc;
static u_int cr3_pcid_temp;
/* these two are accessed from locore.o */
paddr_t cr3_reuse_pcid;
paddr_t cr3_pcid_proc_intel;
/*
* other data structures
*/
pt_entry_t protection_codes[8]; /* maps MI prot to i386 prot code */
int pmap_initialized = 0; /* pmap_init done yet? */
/*
* pv management structures.
*/
struct pool pmap_pv_pool;
/*
* linked list of all non-kernel pmaps
*/
struct pmap_head pmaps;
struct mutex pmaps_lock = MUTEX_INITIALIZER(IPL_VM);
/*
* pool that pmap structures are allocated from
*/
struct pool pmap_pmap_pool;
/*
* When we're freeing a ptp, we need to delay the freeing until all
* tlb shootdown has been done. This is the list of the to-be-freed pages.
*/
TAILQ_HEAD(pg_to_free, vm_page);
/*
* pool that PDPs are allocated from
*/
struct pool pmap_pdp_pool;
void pmap_pdp_ctor(pd_entry_t *);
void pmap_pdp_ctor_intel(pd_entry_t *);
extern vaddr_t msgbuf_vaddr;
extern paddr_t msgbuf_paddr;
extern vaddr_t idt_vaddr; /* we allocate IDT early */
extern paddr_t idt_paddr;
extern vaddr_t lo32_vaddr;
extern vaddr_t lo32_paddr;
vaddr_t virtual_avail;
extern int end;
/*
* local prototypes
*/
void pmap_enter_pv(struct vm_page *, struct pv_entry *, struct pmap *,
vaddr_t, struct vm_page *);
struct vm_page *pmap_get_ptp(struct pmap *, vaddr_t);
struct vm_page *pmap_find_ptp(struct pmap *, vaddr_t, paddr_t, int);
int pmap_find_pte_direct(struct pmap *pm, vaddr_t va, pt_entry_t **pd, int *offs);
void pmap_free_ptp(struct pmap *, struct vm_page *,
vaddr_t, struct pg_to_free *);
void pmap_freepage(struct pmap *, struct vm_page *, int, struct pg_to_free *);
#ifdef MULTIPROCESSOR
static int pmap_is_active(struct pmap *, struct cpu_info *);
#endif
paddr_t pmap_map_ptes(struct pmap *);
struct pv_entry *pmap_remove_pv(struct vm_page *, struct pmap *, vaddr_t);
void pmap_do_remove(struct pmap *, vaddr_t, vaddr_t, int);
void pmap_remove_ept(struct pmap *, vaddr_t, vaddr_t);
void pmap_do_remove_ept(struct pmap *, vaddr_t);
int pmap_enter_ept(struct pmap *, vaddr_t, paddr_t, vm_prot_t);
int pmap_remove_pte(struct pmap *, struct vm_page *, pt_entry_t *,
vaddr_t, int, struct pv_entry **);
void pmap_remove_ptes(struct pmap *, struct vm_page *, vaddr_t,
vaddr_t, vaddr_t, int, struct pv_entry **);
#define PMAP_REMOVE_ALL 0 /* remove all mappings */
#define PMAP_REMOVE_SKIPWIRED 1 /* skip wired mappings */
void pmap_unmap_ptes(struct pmap *, paddr_t);
int pmap_get_physpage(vaddr_t, int, paddr_t *);
int pmap_pdes_valid(vaddr_t, pd_entry_t *);
void pmap_alloc_level(vaddr_t, int, long *);
static inline
void pmap_sync_flags_pte(struct vm_page *, u_long);
void pmap_tlb_shootpage(struct pmap *, vaddr_t, int);
void pmap_tlb_shootrange(struct pmap *, vaddr_t, vaddr_t, int);
void pmap_tlb_shoottlb(struct pmap *, int);
#ifdef MULTIPROCESSOR
void pmap_tlb_shootwait(void);
#else
#define pmap_tlb_shootwait() do { } while (0)
#endif
/*
* p m a p i n l i n e h e l p e r f u n c t i o n s
*/
/*
* pmap_is_curpmap: is this pmap the one currently loaded [in %cr3]?
* of course the kernel is always loaded
*/
static inline int
pmap_is_curpmap(struct pmap *pmap)
{
return((pmap == pmap_kernel()) ||
(pmap->pm_pdirpa == (rcr3() & CR3_PADDR)));
}
/*
* pmap_is_active: is this pmap loaded into the specified processor's %cr3?
*/
#ifdef MULTIPROCESSOR
static inline int
pmap_is_active(struct pmap *pmap, struct cpu_info *ci)
{
return pmap == pmap_kernel() || pmap == ci->ci_proc_pmap;
}
#endif
static inline u_int
pmap_pte2flags(u_long pte)
{
return (((pte & PG_U) ? PG_PMAP_REF : 0) |
((pte & PG_M) ? PG_PMAP_MOD : 0));
}
static inline void
pmap_sync_flags_pte(struct vm_page *pg, u_long pte)
{
if (pte & (PG_U|PG_M)) {
atomic_setbits_int(&pg->pg_flags, pmap_pte2flags(pte));
}
}
/*
* pmap_map_ptes: map a pmap's PTEs into KVM
*
* This should not be done for EPT pmaps
*/
paddr_t
pmap_map_ptes(struct pmap *pmap)
{
paddr_t cr3;
KASSERT(pmap->pm_type != PMAP_TYPE_EPT);
/* the kernel's pmap is always accessible */
if (pmap == pmap_kernel())
return 0;
/*
* Lock the target map before switching to its page tables to
* guarantee other CPUs have finished changing the tables before
* we potentially start caching table and TLB entries.
*/
mtx_enter(&pmap->pm_mtx);
cr3 = rcr3();
KASSERT((cr3 & CR3_PCID) == PCID_KERN ||
(cr3 & CR3_PCID) == PCID_PROC);
if (pmap->pm_pdirpa == (cr3 & CR3_PADDR))
cr3 = 0;
else {
cr3 |= cr3_reuse_pcid;
lcr3(pmap->pm_pdirpa | cr3_pcid_temp);
}
return cr3;
}
void
pmap_unmap_ptes(struct pmap *pmap, paddr_t save_cr3)
{
if (pmap != pmap_kernel())
mtx_leave(&pmap->pm_mtx);
if (save_cr3 != 0)
lcr3(save_cr3);
}
int
pmap_find_pte_direct(struct pmap *pm, vaddr_t va, pt_entry_t **pd, int *offs)
{
u_long mask, shift;
pd_entry_t pde;
paddr_t pdpa;
int lev;
pdpa = pm->pm_pdirpa;
shift = L4_SHIFT;
mask = L4_MASK;
for (lev = PTP_LEVELS; lev > 0; lev--) {
*pd = (pd_entry_t *)PMAP_DIRECT_MAP(pdpa);
*offs = (VA_SIGN_POS(va) & mask) >> shift;
pde = (*pd)[*offs];
/* Large pages are different, break early if we run into one. */
if ((pde & (PG_PS|PG_V)) != PG_V)
return (lev - 1);
pdpa = ((*pd)[*offs] & PG_FRAME);
/* 4096/8 == 512 == 2^9 entries per level */
shift -= 9;
mask >>= 9;
}
return (0);
}
/*
* p m a p k e n t e r f u n c t i o n s
*
* functions to quickly enter/remove pages from the kernel address
* space. pmap_kremove is exported to MI kernel. we make use of
* the recursive PTE mappings.
*/
/*
* pmap_kenter_pa: enter a kernel mapping without R/M (pv_entry) tracking
*
* => no need to lock anything, assume va is already allocated
* => should be faster than normal pmap enter function
*/
void
pmap_kenter_pa(vaddr_t va, paddr_t pa, vm_prot_t prot)
{
pt_entry_t *pte, opte, npte;
pte = kvtopte(va);
npte = (pa & PMAP_PA_MASK) | ((prot & PROT_WRITE) ? PG_RW : PG_RO) |
((pa & PMAP_NOCACHE) ? PG_N : 0) |
((pa & PMAP_WC) ? pmap_pg_wc : 0) | PG_V;
/* special 1:1 mappings in the first 2MB must not be global */
if (va >= (vaddr_t)NBPD_L2)
npte |= pg_g_kern;
if (!(prot & PROT_EXEC))
npte |= pg_nx;
opte = pmap_pte_set(pte, npte);
#ifdef LARGEPAGES
/* XXX For now... */
if (opte & PG_PS)
panic("%s: PG_PS", __func__);
#endif
if (pmap_valid_entry(opte)) {
if (pa & PMAP_NOCACHE && (opte & PG_N) == 0)
wbinvd_on_all_cpus();
/* This shouldn't happen */
pmap_tlb_shootpage(pmap_kernel(), va, 1);
pmap_tlb_shootwait();
}
}
/*
* pmap_kremove: remove a kernel mapping(s) without R/M (pv_entry) tracking
*
* => no need to lock anything
* => caller must dispose of any vm_page mapped in the va range
* => note: not an inline function
* => we assume the va is page aligned and the len is a multiple of PAGE_SIZE
* => we assume kernel only unmaps valid addresses and thus don't bother
* checking the valid bit before doing TLB flushing
*/
void
pmap_kremove(vaddr_t sva, vsize_t len)
{
pt_entry_t *pte, opte;
vaddr_t va, eva;
eva = sva + len;
for (va = sva; va != eva; va += PAGE_SIZE) {
pte = kvtopte(va);
opte = pmap_pte_set(pte, 0);
#ifdef LARGEPAGES
KASSERT((opte & PG_PS) == 0);
#endif
KASSERT((opte & PG_PVLIST) == 0);
}
pmap_tlb_shootrange(pmap_kernel(), sva, eva, 1);
pmap_tlb_shootwait();
}
/*
* pmap_set_pml4_early
*
* Utility function to map 2GB of 2MB pages to 'pa'. The VA that is assigned
* is the pml4 entry for 'early mappings' (see pmap.h). This function is used
* by display drivers that need to map their framebuffers early, before the
* pmap is fully initialized (eg, to show panic messages).
*
* Users of this function must call pmap_clear_pml4_early to remove the
* mapping when finished.
*
* Parameters:
* pa: phys addr to map
*
* Return value:
* VA mapping to 'pa'. This mapping is 2GB in size and starts at the base
* of the 2MB region containing 'va'.
*/
vaddr_t
pmap_set_pml4_early(paddr_t pa)
{
extern paddr_t early_pte_pages;
pt_entry_t *pml4e, *pte;
int i, j, off;
paddr_t curpa;
vaddr_t va;
pml4e = (pt_entry_t *)(proc0.p_addr->u_pcb.pcb_cr3 + KERNBASE);
pml4e[PDIR_SLOT_EARLY] = (pd_entry_t)early_pte_pages | PG_V | PG_RW;
off = pa & PAGE_MASK_L2;
curpa = pa & L2_FRAME;
pte = (pt_entry_t *)PMAP_DIRECT_MAP(early_pte_pages);
memset(pte, 0, 3 * NBPG);
pte[0] = (early_pte_pages + NBPG) | PG_V | PG_RW;
pte[1] = (early_pte_pages + 2 * NBPG) | PG_V | PG_RW;
pte = (pt_entry_t *)PMAP_DIRECT_MAP(early_pte_pages + NBPG);
for (i = 0; i < 2; i++) {
/* 2 early pages of mappings */
for (j = 0; j < 512; j++) {
/* j[0..511] : 2MB mappings per page */
pte[(i * 512) + j] = curpa | PG_V | PG_RW | PG_PS;
curpa += (2 * 1024 * 1024);
}
}
va = (vaddr_t)((PDIR_SLOT_EARLY * 512ULL) << L3_SHIFT) + off;
return VA_SIGN_NEG(va);
}
/*
* pmap_clear_pml4_early
*
* Clears the mapping previously established with pmap_set_pml4_early.
*/
void
pmap_clear_pml4_early(void)
{
extern paddr_t early_pte_pages;
pt_entry_t *pml4e, *pte;
pte = (pt_entry_t *)PMAP_DIRECT_MAP(early_pte_pages);
memset(pte, 0, 3 * NBPG);
pml4e = (pd_entry_t *)pmap_kernel()->pm_pdir;
pml4e[PDIR_SLOT_EARLY] = 0;
tlbflush();
}
/*
* p m a p i n i t f u n c t i o n s
*
* pmap_bootstrap and pmap_init are called during system startup
* to init the pmap module. pmap_bootstrap() does a low level
* init just to get things rolling. pmap_init() finishes the job.
*/
/*
* pmap_bootstrap: get the system in a state where it can run with VM
* properly enabled (called before main()). the VM system is
* fully init'd later...
*/
paddr_t
pmap_bootstrap(paddr_t first_avail, paddr_t max_pa)
{
vaddr_t kva_start = VM_MIN_KERNEL_ADDRESS;
struct pmap *kpm;
int curslot, i, j, p;
long ndmpdp;
paddr_t dmpd, dmpdp, start_cur, cur_pa;
vaddr_t kva, kva_end;
pt_entry_t *pml3, *pml2;
/*
* define the boundaries of the managed kernel virtual address
* space.
*/
virtual_avail = kva_start; /* first free KVA */
/*
* set up protection_codes: we need to be able to convert from
* a MI protection code (some combo of VM_PROT...) to something
* we can jam into a i386 PTE.
*/
protection_codes[PROT_NONE] = pg_nx; /* --- */
protection_codes[PROT_EXEC] = PG_RO; /* --x */
protection_codes[PROT_READ] = PG_RO | pg_nx; /* -r- */
protection_codes[PROT_READ | PROT_EXEC] = PG_RO; /* -rx */
protection_codes[PROT_WRITE] = PG_RW | pg_nx; /* w-- */
protection_codes[PROT_WRITE | PROT_EXEC] = PG_RW; /* w-x */
protection_codes[PROT_WRITE | PROT_READ] = PG_RW | pg_nx; /* wr- */
protection_codes[PROT_READ | PROT_WRITE | PROT_EXEC] = PG_RW; /* wrx */
/*
* now we init the kernel's pmap
*
* the kernel pmap's pm_obj is not used for much. however, in
* user pmaps the pm_obj contains the list of active PTPs.
* the pm_obj currently does not have a pager.
*/
kpm = pmap_kernel();
for (i = 0; i < PTP_LEVELS - 1; i++) {
uvm_obj_init(&kpm->pm_obj[i], &pmap_pager, 1);
kpm->pm_ptphint[i] = NULL;
}
memset(&kpm->pm_list, 0, sizeof(kpm->pm_list)); /* pm_list not used */
kpm->pm_pdir = (pd_entry_t *)(proc0.p_addr->u_pcb.pcb_cr3 + KERNBASE);
kpm->pm_pdirpa = proc0.p_addr->u_pcb.pcb_cr3;
kpm->pm_stats.wired_count = kpm->pm_stats.resident_count =
atop(kva_start - VM_MIN_KERNEL_ADDRESS);
/*
* the above is just a rough estimate and not critical to the proper
* operation of the system.
*/
kpm->pm_type = PMAP_TYPE_NORMAL;
curpcb->pcb_pmap = kpm; /* proc0's pcb */
/*
* Configure and enable PCID use if supported.
* Currently we require INVPCID support.
*/
if ((cpu_ecxfeature & CPUIDECX_PCID) && cpuid_level >= 0x07) {
uint32_t ebx, dummy;
CPUID_LEAF(0x7, 0, dummy, ebx, dummy, dummy);
if (ebx & SEFF0EBX_INVPCID) {
pmap_use_pcid = 1;
/*
* We cannot use global mappings because
* invpcid function 0 does not invalidate global
* mappings. The hardware can cache kernel
* mappings based on PCID_KERN, i.e. there is no
* need for global mappings.
*/
pg_g_kern = 0;
lcr4( rcr4() | CR4_PCIDE );
cr3_pcid_proc = PCID_PROC;
cr3_pcid_temp = PCID_TEMP;
cr3_reuse_pcid = CR3_REUSE_PCID;
cr3_pcid_proc_intel = PCID_PROC_INTEL;
}
}
/*
* Add PG_G attribute to already mapped kernel pages. pg_g_kern
* is calculated in locore0.S and may be set to:
*
* 0 if this CPU does not safely support global pages in the kernel
* (Intel/Meltdown)
* PG_G if this CPU does safely support global pages in the kernel
* (AMD)
*/
#if KERNBASE == VM_MIN_KERNEL_ADDRESS
for (kva = VM_MIN_KERNEL_ADDRESS ; kva < virtual_avail ;
#else
kva_end = roundup((vaddr_t)&end, PAGE_SIZE);
for (kva = KERNBASE; kva < kva_end ;
#endif
kva += PAGE_SIZE) {
unsigned long p1i = pl1_i(kva);
if (pmap_valid_entry(PTE_BASE[p1i]))
PTE_BASE[p1i] |= pg_g_kern;
}
/*
* Map the direct map. The first 4GB were mapped in locore, here
* we map the rest if it exists. We actually use the direct map
* here to set up the page tables, we're assuming that we're still
* operating in the lower 4GB of memory.
*
* Map (up to) the first 512GB of physical memory first. This part
* is handled differently than physical memory > 512GB since we have
* already mapped part of this range in locore0.
*/
ndmpdp = (max_pa + NBPD_L3 - 1) >> L3_SHIFT;
if (ndmpdp < NDML2_ENTRIES)
ndmpdp = NDML2_ENTRIES; /* At least 4GB */
if (ndmpdp > 512)
ndmpdp = 512; /* At most 512GB */
dmpdp = kpm->pm_pdir[PDIR_SLOT_DIRECT] & PG_FRAME;
dmpd = first_avail; first_avail += ndmpdp * PAGE_SIZE;
for (i = NDML2_ENTRIES; i < NPDPG * ndmpdp; i++) {
paddr_t pdp;
vaddr_t va;
pdp = (paddr_t)&(((pd_entry_t *)dmpd)[i]);
va = PMAP_DIRECT_MAP(pdp);
*((pd_entry_t *)va) = ((paddr_t)i << L2_SHIFT);
*((pd_entry_t *)va) |= PG_RW | PG_V | PG_PS | pg_g_kern | PG_U |
PG_M | pg_nx;
}
for (i = NDML2_ENTRIES; i < ndmpdp; i++) {
paddr_t pdp;
vaddr_t va;
pdp = (paddr_t)&(((pd_entry_t *)dmpdp)[i]);
va = PMAP_DIRECT_MAP(pdp);
*((pd_entry_t *)va) = dmpd + (i << PAGE_SHIFT);
*((pd_entry_t *)va) |= PG_RW | PG_V | PG_U | PG_M | pg_nx;
}
kpm->pm_pdir[PDIR_SLOT_DIRECT] = dmpdp | PG_V | PG_KW | PG_U |
PG_M | pg_nx;
/* Map any remaining physical memory > 512GB */
for (curslot = 1 ; curslot < NUM_L4_SLOT_DIRECT ; curslot++) {
/*
* Start of current range starts at PA (curslot) * 512GB
*/
start_cur = (paddr_t)(curslot * NBPD_L4);
if (max_pa > start_cur) {
/* Next 512GB, new PML4e and L3(512GB) page */
dmpd = first_avail; first_avail += PAGE_SIZE;
pml3 = (pt_entry_t *)PMAP_DIRECT_MAP(dmpd);
kpm->pm_pdir[PDIR_SLOT_DIRECT + curslot] = dmpd |
PG_KW | PG_V | PG_U | PG_M | pg_nx;
/* Calculate full 1GB pages in this 512GB region */
p = ((max_pa - start_cur) >> L3_SHIFT);
/* Check if a partial (<1GB) page remains */
if (max_pa & L2_MASK)
p++;
/*
* Handle the case where this range is full and there
* is still more memory after (p would be > 512).
*/
if (p > NPDPG)
p = NPDPG;
/* Allocate 'p' L2(1GB) pages and populate */
for (i = 0; i < p; i++) {
dmpd = first_avail; first_avail += PAGE_SIZE;
pml2 = (pt_entry_t *)PMAP_DIRECT_MAP(dmpd);
pml3[i] = dmpd |
PG_RW | PG_V | PG_U | PG_M | pg_nx;
cur_pa = start_cur + (i << L3_SHIFT);
j = 0;
while (cur_pa < max_pa && j < NPDPG) {
pml2[j] = curslot * NBPD_L4 +
(uint64_t)i * NBPD_L3 +
(uint64_t)j * NBPD_L2;
pml2[j] |= PG_RW | PG_V | pg_g_kern |
PG_U | PG_M | pg_nx | PG_PS;
cur_pa += NBPD_L2;
j++;
}
}
}
}
tlbflush();
msgbuf_vaddr = virtual_avail;
virtual_avail += round_page(MSGBUFSIZE);
idt_vaddr = virtual_avail;
virtual_avail += 2 * PAGE_SIZE;
idt_paddr = first_avail; /* steal a page */
first_avail += 2 * PAGE_SIZE;
#if defined(MULTIPROCESSOR) || \
(NACPI > 0 && !defined(SMALL_KERNEL))
/*
* Grab a page below 4G for things that need it (i.e.
* having an initial %cr3 for the MP trampoline).
*/
lo32_vaddr = virtual_avail;
virtual_avail += PAGE_SIZE;
lo32_paddr = first_avail;
first_avail += PAGE_SIZE;
#endif
/*
* init the global lists.
*/
LIST_INIT(&pmaps);
/*
* initialize the pmap pools.
*/
pool_init(&pmap_pmap_pool, sizeof(struct pmap), 0, IPL_VM, 0,
"pmappl", NULL);
pool_init(&pmap_pv_pool, sizeof(struct pv_entry), 0, IPL_VM, 0,
"pvpl", &pool_allocator_single);
pool_sethiwat(&pmap_pv_pool, 32 * 1024);
/*
* initialize the PDE pool.
*/
pool_init(&pmap_pdp_pool, PAGE_SIZE, 0, IPL_VM, 0,
"pdppl", &pool_allocator_single);
kpm->pm_pdir_intel = NULL;
kpm->pm_pdirpa_intel = 0;
/*
* ensure the TLB is sync'd with reality by flushing it...
*/
tlbflush();
return first_avail;
}
/*
* pmap_randomize
*
* Randomizes the location of the kernel pmap
*/
void
pmap_randomize(void)
{
pd_entry_t *pml4va, *oldpml4va;
paddr_t pml4pa;
int i;
pml4va = km_alloc(PAGE_SIZE, &kv_page, &kp_zero, &kd_nowait);
if (pml4va == NULL)
panic("%s: km_alloc failed", __func__);
/* Copy old PML4 page to new one */
oldpml4va = pmap_kernel()->pm_pdir;
memcpy(pml4va, oldpml4va, PAGE_SIZE);
/* Switch to new PML4 */
pmap_extract(pmap_kernel(), (vaddr_t)pml4va, &pml4pa);
lcr3(pml4pa);
/* Fixup pmap_kernel and proc0's %cr3 */
pmap_kernel()->pm_pdirpa = pml4pa;
pmap_kernel()->pm_pdir = pml4va;
proc0.p_addr->u_pcb.pcb_cr3 = pml4pa;
/* Fixup recursive PTE PML4E slot. We are only changing the PA */
pml4va[PDIR_SLOT_PTE] = pml4pa | (pml4va[PDIR_SLOT_PTE] & ~PG_FRAME);
for (i = 0; i < NPDPG; i++) {
/* PTE slot already handled earlier */
if (i == PDIR_SLOT_PTE)
continue;
if (pml4va[i] & PG_FRAME)
pmap_randomize_level(&pml4va[i], 3);
}
/* Wipe out bootstrap PML4 */
memset(oldpml4va, 0, PAGE_SIZE);
tlbflush();
}
void
pmap_randomize_level(pd_entry_t *pde, int level)
{
pd_entry_t *new_pd_va;
paddr_t old_pd_pa, new_pd_pa;
vaddr_t old_pd_va;
struct vm_page *pg;
int i;
if (level == 0)
return;
if (level < PTP_LEVELS - 1 && (*pde & PG_PS))
return;
new_pd_va = km_alloc(PAGE_SIZE, &kv_page, &kp_zero, &kd_nowait);
if (new_pd_va == NULL)
panic("%s: cannot allocate page for L%d page directory",
__func__, level);
old_pd_pa = *pde & PG_FRAME;
old_pd_va = PMAP_DIRECT_MAP(old_pd_pa);
pmap_extract(pmap_kernel(), (vaddr_t)new_pd_va, &new_pd_pa);
memcpy(new_pd_va, (void *)old_pd_va, PAGE_SIZE);
*pde = new_pd_pa | (*pde & ~PG_FRAME);
tlbflush();
memset((void *)old_pd_va, 0, PAGE_SIZE);
pg = PHYS_TO_VM_PAGE(old_pd_pa);
if (pg != NULL) {
pg->wire_count--;
pmap_kernel()->pm_stats.resident_count--;
if (pg->wire_count <= 1)
uvm_pagefree(pg);
}
for (i = 0; i < NPDPG; i++)
if (new_pd_va[i] & PG_FRAME)
pmap_randomize_level(&new_pd_va[i], level - 1);
}
/*
* Pre-allocate PTPs for low memory, so that 1:1 mappings for various
* trampoline code can be entered.
*/
paddr_t
pmap_prealloc_lowmem_ptps(paddr_t first_avail)
{
pd_entry_t *pdes;
int level;
paddr_t newp;
pdes = pmap_kernel()->pm_pdir;
level = PTP_LEVELS;
for (;;) {
newp = first_avail; first_avail += PAGE_SIZE;
memset((void *)PMAP_DIRECT_MAP(newp), 0, PAGE_SIZE);
pdes[pl_i(0, level)] = (newp & PG_FRAME) | PG_V | PG_RW;
level--;
if (level <= 1)
break;
pdes = normal_pdes[level - 2];
}