efirt_machdep.c

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
    1 /*-
    2  * Copyright (c) 2004 Marcel Moolenaar
    3  * Copyright (c) 2001 Doug Rabson
    4  * Copyright (c) 2016 The FreeBSD Foundation
    5  * All rights reserved.
    6  *
    7  * Portions of this software were developed by Konstantin Belousov
    8  * under sponsorship from the FreeBSD Foundation.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  *
   19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   29  * SUCH DAMAGE.
   30  */
   31 
   32 #include <sys/cdefs.h>
   33 __FBSDID("$FreeBSD: releng/11.2/sys/amd64/amd64/efirt_machdep.c 332028 2018-04-04 13:58:18Z kevans $");
   34 
   35 #include <sys/param.h>
   36 #include <sys/efi.h>
   37 #include <sys/kernel.h>
   38 #include <sys/linker.h>
   39 #include <sys/lock.h>
   40 #include <sys/module.h>
   41 #include <sys/mutex.h>
   42 #include <sys/clock.h>
   43 #include <sys/proc.h>
   44 #include <sys/rwlock.h>
   45 #include <sys/sched.h>
   46 #include <sys/sysctl.h>
   47 #include <sys/systm.h>
   48 #include <sys/vmmeter.h>
   49 #include <isa/rtc.h>
   50 #include <machine/fpu.h>
   51 #include <machine/efi.h>
   52 #include <machine/metadata.h>
   53 #include <machine/md_var.h>
   54 #include <machine/smp.h>
   55 #include <machine/vmparam.h>
   56 #include <vm/vm.h>
   57 #include <vm/pmap.h>
   58 #include <vm/vm_map.h>
   59 #include <vm/vm_object.h>
   60 #include <vm/vm_page.h>
   61 #include <vm/vm_pager.h>
   62 
   63 static pml4_entry_t *efi_pml4;
   64 static vm_object_t obj_1t1_pt;
   65 static vm_page_t efi_pml4_page;
   66 static vm_pindex_t efi_1t1_idx;
   67 
   68 void
   69 efi_destroy_1t1_map(void)
   70 {
   71         vm_page_t m;
   72 
   73         if (obj_1t1_pt != NULL) {
   74                 VM_OBJECT_RLOCK(obj_1t1_pt);
   75                 TAILQ_FOREACH(m, &obj_1t1_pt->memq, listq)
   76                         m->wire_count = 0;
   77                 atomic_subtract_int(&vm_cnt.v_wire_count,
   78                     obj_1t1_pt->resident_page_count);
   79                 VM_OBJECT_RUNLOCK(obj_1t1_pt);
   80                 vm_object_deallocate(obj_1t1_pt);
   81         }
   82 
   83         obj_1t1_pt = NULL;
   84         efi_pml4 = NULL;
   85         efi_pml4_page = NULL;
   86 }
   87 
   88 static vm_page_t
   89 efi_1t1_page(void)
   90 {
   91 
   92         return (vm_page_grab(obj_1t1_pt, efi_1t1_idx++, VM_ALLOC_NOBUSY |
   93             VM_ALLOC_WIRED | VM_ALLOC_ZERO));
   94 }
   95 
   96 static pt_entry_t *
   97 efi_1t1_pte(vm_offset_t va)
   98 {
   99         pml4_entry_t *pml4e;
  100         pdp_entry_t *pdpe;
  101         pd_entry_t *pde;
  102         pt_entry_t *pte;
  103         vm_page_t m;
  104         vm_pindex_t pml4_idx, pdp_idx, pd_idx;
  105         vm_paddr_t mphys;
  106 
  107         pml4_idx = pmap_pml4e_index(va);
  108         pml4e = &efi_pml4[pml4_idx];
  109         if (*pml4e == 0) {
  110                 m = efi_1t1_page();
  111                 mphys =  VM_PAGE_TO_PHYS(m);
  112                 *pml4e = mphys | X86_PG_RW | X86_PG_V;
  113         } else {
  114                 mphys = *pml4e & ~PAGE_MASK;
  115         }
  116 
  117         pdpe = (pdp_entry_t *)PHYS_TO_DMAP(mphys);
  118         pdp_idx = pmap_pdpe_index(va);
  119         pdpe += pdp_idx;
  120         if (*pdpe == 0) {
  121                 m = efi_1t1_page();
  122                 mphys =  VM_PAGE_TO_PHYS(m);
  123                 *pdpe = mphys | X86_PG_RW | X86_PG_V;
  124         } else {
  125                 mphys = *pdpe & ~PAGE_MASK;
  126         }
  127 
  128         pde = (pd_entry_t *)PHYS_TO_DMAP(mphys);
  129         pd_idx = pmap_pde_index(va);
  130         pde += pd_idx;
  131         if (*pde == 0) {
  132                 m = efi_1t1_page();
  133                 mphys = VM_PAGE_TO_PHYS(m);
  134                 *pde = mphys | X86_PG_RW | X86_PG_V;
  135         } else {
  136                 mphys = *pde & ~PAGE_MASK;
  137         }
  138 
  139         pte = (pt_entry_t *)PHYS_TO_DMAP(mphys);
  140         pte += pmap_pte_index(va);
  141         KASSERT(*pte == 0, ("va %#jx *pt %#jx", va, *pte));
  142 
  143         return (pte);
  144 }
  145 
  146 bool
  147 efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz)
  148 {
  149         struct efi_md *p;
  150         pt_entry_t *pte;
  151         vm_offset_t va;
  152         uint64_t idx;
  153         int bits, i, mode;
  154 
  155         obj_1t1_pt = vm_pager_allocate(OBJT_PHYS, NULL, ptoa(1 +
  156             NPML4EPG + NPML4EPG * NPDPEPG + NPML4EPG * NPDPEPG * NPDEPG),
  157             VM_PROT_ALL, 0, NULL);
  158         efi_1t1_idx = 0;
  159         VM_OBJECT_WLOCK(obj_1t1_pt);
  160         efi_pml4_page = efi_1t1_page();
  161         VM_OBJECT_WUNLOCK(obj_1t1_pt);
  162         efi_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(efi_pml4_page));
  163         pmap_pinit_pml4(efi_pml4_page);
  164 
  165         for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
  166             descsz)) {
  167                 if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
  168                         continue;
  169                 if (p->md_virt != NULL && (uint64_t)p->md_virt != p->md_phys) {
  170                         if (bootverbose)
  171                                 printf("EFI Runtime entry %d is mapped\n", i);
  172                         goto fail;
  173                 }
  174                 if ((p->md_phys & EFI_PAGE_MASK) != 0) {
  175                         if (bootverbose)
  176                                 printf("EFI Runtime entry %d is not aligned\n",
  177                                     i);
  178                         goto fail;
  179                 }
  180                 if (p->md_phys + p->md_pages * EFI_PAGE_SIZE < p->md_phys ||
  181                     p->md_phys + p->md_pages * EFI_PAGE_SIZE >=
  182                     VM_MAXUSER_ADDRESS) {
  183                         printf("EFI Runtime entry %d is not in mappable for RT:"
  184                             "base %#016jx %#jx pages\n",
  185                             i, (uintmax_t)p->md_phys,
  186                             (uintmax_t)p->md_pages);
  187                         goto fail;
  188                 }
  189                 if ((p->md_attr & EFI_MD_ATTR_WB) != 0)
  190                         mode = VM_MEMATTR_WRITE_BACK;
  191                 else if ((p->md_attr & EFI_MD_ATTR_WT) != 0)
  192                         mode = VM_MEMATTR_WRITE_THROUGH;
  193                 else if ((p->md_attr & EFI_MD_ATTR_WC) != 0)
  194                         mode = VM_MEMATTR_WRITE_COMBINING;
  195                 else if ((p->md_attr & EFI_MD_ATTR_WP) != 0)
  196                         mode = VM_MEMATTR_WRITE_PROTECTED;
  197                 else if ((p->md_attr & EFI_MD_ATTR_UC) != 0)
  198                         mode = VM_MEMATTR_UNCACHEABLE;
  199                 else {
  200                         if (bootverbose)
  201                                 printf("EFI Runtime entry %d mapping "
  202                                     "attributes unsupported\n", i);
  203                         mode = VM_MEMATTR_UNCACHEABLE;
  204                 }
  205                 bits = pmap_cache_bits(kernel_pmap, mode, FALSE) | X86_PG_RW |
  206                     X86_PG_V;
  207                 VM_OBJECT_WLOCK(obj_1t1_pt);
  208                 for (va = p->md_phys, idx = 0; idx < p->md_pages; idx++,
  209                     va += PAGE_SIZE) {
  210                         pte = efi_1t1_pte(va);
  211                         pte_store(pte, va | bits);
  212                 }
  213                 VM_OBJECT_WUNLOCK(obj_1t1_pt);
  214         }
  215 
  216         return (true);
  217 
  218 fail:
  219         efi_destroy_1t1_map();
  220         return (false);
  221 }
  222 
  223 /*
  224  * Create an environment for the EFI runtime code call.  The most
  225  * important part is creating the required 1:1 physical->virtual
  226  * mappings for the runtime segments.  To do that, we manually create
  227  * page table which unmap userspace but gives correct kernel mapping.
  228  * The 1:1 mappings for runtime segments usually occupy low 4G of the
  229  * physical address map.
  230  *
  231  * The 1:1 mappings were chosen over the SetVirtualAddressMap() EFI RT
  232  * service, because there are some BIOSes which fail to correctly
  233  * relocate itself on the call, requiring both 1:1 and virtual
  234  * mapping.  As result, we must provide 1:1 mapping anyway, so no
  235  * reason to bother with the virtual map, and no need to add a
  236  * complexity into loader.
  237  *
  238  * The fpu_kern_enter() call allows firmware to use FPU, as mandated
  239  * by the specification.  In particular, CR0.TS bit is cleared.  Also
  240  * it enters critical section, giving us neccessary protection against
  241  * context switch.
  242  *
  243  * There is no need to disable interrupts around the change of %cr3,
  244  * the kernel mappings are correct, while we only grabbed the
  245  * userspace portion of VA.  Interrupts handlers must not access
  246  * userspace.  Having interrupts enabled fixes the issue with
  247  * firmware/SMM long operation, which would negatively affect IPIs,
  248  * esp. TLB shootdown requests.
  249  */
  250 int
  251 efi_arch_enter(void)
  252 {
  253         pmap_t curpmap;
  254 
  255         curpmap = PCPU_GET(curpmap);
  256         PMAP_LOCK_ASSERT(curpmap, MA_OWNED);
  257 
  258         /*
  259          * IPI TLB shootdown handler invltlb_pcid_handler() reloads
  260          * %cr3 from the curpmap->pm_cr3, which would disable runtime
  261          * segments mappings.  Block the handler's action by setting
  262          * curpmap to impossible value.  See also comment in
  263          * pmap.c:pmap_activate_sw().
  264          */
  265         if (pmap_pcid_enabled && !invpcid_works)
  266                 PCPU_SET(curpmap, NULL);
  267 
  268         load_cr3(VM_PAGE_TO_PHYS(efi_pml4_page) | (pmap_pcid_enabled ?
  269             curpmap->pm_pcids[PCPU_GET(cpuid)].pm_pcid : 0));
  270         /*
  271          * If PCID is enabled, the clear CR3_PCID_SAVE bit in the loaded %cr3
  272          * causes TLB invalidation.
  273          */
  274         if (!pmap_pcid_enabled)
  275                 invltlb();
  276         return (0);
  277 }
  278 
  279 void
  280 efi_arch_leave(void)
  281 {
  282         pmap_t curpmap;
  283 
  284         curpmap = &curproc->p_vmspace->vm_pmap;
  285         if (pmap_pcid_enabled && !invpcid_works)
  286                 PCPU_SET(curpmap, curpmap);
  287         load_cr3(curpmap->pm_cr3 | (pmap_pcid_enabled ?
  288             curpmap->pm_pcids[PCPU_GET(cpuid)].pm_pcid : 0));
  289         if (!pmap_pcid_enabled)
  290                 invltlb();
  291 }
  292 
  293 /* XXX debug stuff */
  294 static int
  295 efi_time_sysctl_handler(SYSCTL_HANDLER_ARGS)
  296 {
  297         struct efi_tm tm;
  298         int error, val;
  299 
  300         val = 0;
  301         error = sysctl_handle_int(oidp, &val, 0, req);
  302         if (error != 0 || req->newptr == NULL)
  303                 return (error);
  304         error = efi_get_time(&tm);
  305         if (error == 0) {
  306                 uprintf("EFI reports: Year %d Month %d Day %d Hour %d Min %d "
  307                     "Sec %d\n", tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
  308                     tm.tm_min, tm.tm_sec);
  309         }
  310         return (error);
  311 }
  312 
  313 SYSCTL_PROC(_debug, OID_AUTO, efi_time, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
  314     efi_time_sysctl_handler, "I", "");
Cache object: cb5e944f84864d47cb131a94c4aae0a6
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.
FreeBSD/Linux Kernel Cross Reference sys/amd64/amd64/efirt_machdep.c

FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/efirt_machdep.c
