1 /*- 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 3 * Copyright (c) 2014 The FreeBSD Foundation 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #define __ELF_WORD_SIZE 64 29 #include <sys/param.h> 30 #include <sys/exec.h> 31 #include <sys/linker.h> 32 #include <string.h> 33 #include <machine/elf.h> 34 #include <stand.h> 35 #include <vm/vm.h> 36 #include <vm/pmap.h> 37 38 #include <efi.h> 39 #include <efilib.h> 40 41 #include "bootstrap.h" 42 43 #include "loader_efi.h" 44 45 extern int bi_load(char *args, vm_offset_t *modulep, vm_offset_t *kernendp, 46 bool exit_bs); 47 48 static int elf64_exec(struct preloaded_file *amp); 49 static int elf64_obj_exec(struct preloaded_file *amp); 50 51 static struct file_format amd64_elf = { 52 .l_load = elf64_loadfile, 53 .l_exec = elf64_exec, 54 }; 55 static struct file_format amd64_elf_obj = { 56 .l_load = elf64_obj_loadfile, 57 .l_exec = elf64_obj_exec, 58 }; 59 60 extern struct file_format multiboot2; 61 extern struct file_format multiboot2_obj; 62 63 struct file_format *file_formats[] = { 64 &multiboot2, 65 &multiboot2_obj, 66 &amd64_elf, 67 &amd64_elf_obj, 68 NULL 69 }; 70 71 static pml4_entry_t *PT4; 72 static pdp_entry_t *PT3; 73 static pdp_entry_t *PT3_l, *PT3_u; 74 static pd_entry_t *PT2; 75 static pd_entry_t *PT2_l0, *PT2_l1, *PT2_l2, *PT2_l3, *PT2_u0, *PT2_u1; 76 77 extern EFI_PHYSICAL_ADDRESS staging; 78 79 static void (*trampoline)(uint64_t stack, void *copy_finish, uint64_t kernend, 80 uint64_t modulep, pml4_entry_t *pagetable, uint64_t entry); 81 82 extern uintptr_t amd64_tramp; 83 extern uint32_t amd64_tramp_size; 84 85 /* 86 * There is an ELF kernel and one or more ELF modules loaded. 87 * We wish to start executing the kernel image, so make such 88 * preparations as are required, and do so. 89 */ 90 static int 91 elf64_exec(struct preloaded_file *fp) 92 { 93 struct file_metadata *md; 94 Elf_Ehdr *ehdr; 95 vm_offset_t modulep, kernend, trampcode, trampstack; 96 int err, i; 97 bool copy_auto; 98 99 copy_auto = copy_staging == COPY_STAGING_AUTO; 100 if (copy_auto) 101 copy_staging = fp->f_kernphys_relocatable ? 102 COPY_STAGING_DISABLE : COPY_STAGING_ENABLE; 103 104 if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL) 105 return (EFTYPE); 106 ehdr = (Elf_Ehdr *)&(md->md_data); 107 108 trampcode = copy_staging == COPY_STAGING_ENABLE ? 109 (vm_offset_t)0x0000000040000000 /* 1G */ : 110 (vm_offset_t)0x0000000100000000; /* 4G */; 111 err = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 1, 112 (EFI_PHYSICAL_ADDRESS *)&trampcode); 113 if (EFI_ERROR(err)) { 114 printf("Unable to allocate trampoline\n"); 115 if (copy_auto) 116 copy_staging = COPY_STAGING_AUTO; 117 return (ENOMEM); 118 } 119 bzero((void *)trampcode, EFI_PAGE_SIZE); 120 trampstack = trampcode + EFI_PAGE_SIZE - 8; 121 bcopy((void *)&amd64_tramp, (void *)trampcode, amd64_tramp_size); 122 trampoline = (void *)trampcode; 123 124 if (copy_staging == COPY_STAGING_ENABLE) { 125 PT4 = (pml4_entry_t *)0x0000000040000000; /* 1G */ 126 err = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 3, 127 (EFI_PHYSICAL_ADDRESS *)&PT4); 128 if (EFI_ERROR(err)) { 129 printf("Unable to allocate trampoline page table\n"); 130 BS->FreePages(trampcode, 1); 131 if (copy_auto) 132 copy_staging = COPY_STAGING_AUTO; 133 return (ENOMEM); 134 } 135 bzero(PT4, 3 * EFI_PAGE_SIZE); 136 PT3 = &PT4[512]; 137 PT2 = &PT3[512]; 138 139 /* 140 * This is kinda brutal, but every single 1GB VM 141 * memory segment points to the same first 1GB of 142 * physical memory. But it is more than adequate. 143 */ 144 for (i = 0; i < NPTEPG; i++) { 145 /* 146 * Each slot of the L4 pages points to the 147 * same L3 page. 148 */ 149 PT4[i] = (pml4_entry_t)PT3; 150 PT4[i] |= PG_V | PG_RW; 151 152 /* 153 * Each slot of the L3 pages points to the 154 * same L2 page. 155 */ 156 PT3[i] = (pdp_entry_t)PT2; 157 PT3[i] |= PG_V | PG_RW; 158 159 /* 160 * The L2 page slots are mapped with 2MB pages for 1GB. 161 */ 162 PT2[i] = (pd_entry_t)i * (2 * 1024 * 1024); 163 PT2[i] |= PG_V | PG_RW | PG_PS; 164 } 165 } else { 166 PT4 = (pml4_entry_t *)0x0000000100000000; /* 4G */ 167 err = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 9, 168 (EFI_PHYSICAL_ADDRESS *)&PT4); 169 if (EFI_ERROR(err)) { 170 printf("Unable to allocate trampoline page table\n"); 171 BS->FreePages(trampcode, 9); 172 if (copy_auto) 173 copy_staging = COPY_STAGING_AUTO; 174 return (ENOMEM); 175 } 176 177 bzero(PT4, 9 * EFI_PAGE_SIZE); 178 179 PT3_l = &PT4[NPML4EPG * 1]; 180 PT3_u = &PT4[NPML4EPG * 2]; 181 PT2_l0 = &PT4[NPML4EPG * 3]; 182 PT2_l1 = &PT4[NPML4EPG * 4]; 183 PT2_l2 = &PT4[NPML4EPG * 5]; 184 PT2_l3 = &PT4[NPML4EPG * 6]; 185 PT2_u0 = &PT4[NPML4EPG * 7]; 186 PT2_u1 = &PT4[NPML4EPG * 8]; 187 188 /* 1:1 mapping of lower 4G */ 189 PT4[0] = (pml4_entry_t)PT3_l | PG_V | PG_RW; 190 PT3_l[0] = (pdp_entry_t)PT2_l0 | PG_V | PG_RW; 191 PT3_l[1] = (pdp_entry_t)PT2_l1 | PG_V | PG_RW; 192 PT3_l[2] = (pdp_entry_t)PT2_l2 | PG_V | PG_RW; 193 PT3_l[3] = (pdp_entry_t)PT2_l3 | PG_V | PG_RW; 194 for (i = 0; i < 4 * NPDEPG; i++) { 195 PT2_l0[i] = ((pd_entry_t)i << PDRSHIFT) | PG_V | 196 PG_RW | PG_PS; 197 } 198 199 /* mapping of kernel 2G below top */ 200 PT4[NPML4EPG - 1] = (pml4_entry_t)PT3_u | PG_V | PG_RW; 201 PT3_u[NPDPEPG - 2] = (pdp_entry_t)PT2_u0 | PG_V | PG_RW; 202 PT3_u[NPDPEPG - 1] = (pdp_entry_t)PT2_u1 | PG_V | PG_RW; 203 /* compat mapping of phys @0 */ 204 PT2_u0[0] = PG_PS | PG_V | PG_RW; 205 /* this maps past staging area */ 206 for (i = 1; i < 2 * NPDEPG; i++) { 207 PT2_u0[i] = ((pd_entry_t)staging + 208 ((pd_entry_t)i - 1) * NBPDR) | 209 PG_V | PG_RW | PG_PS; 210 } 211 } 212 213 printf("staging %#lx (%scopying) tramp %p PT4 %p\n", 214 staging, copy_staging == COPY_STAGING_ENABLE ? "" : "not ", 215 trampoline, PT4); 216 printf("Start @ 0x%lx ...\n", ehdr->e_entry); 217 218 efi_time_fini(); 219 err = bi_load(fp->f_args, &modulep, &kernend, true); 220 if (err != 0) { 221 efi_time_init(); 222 if (copy_auto) 223 copy_staging = COPY_STAGING_AUTO; 224 return (err); 225 } 226 227 dev_cleanup(); 228 229 trampoline(trampstack, copy_staging == COPY_STAGING_ENABLE ? 230 efi_copy_finish : efi_copy_finish_nop, kernend, modulep, 231 PT4, ehdr->e_entry); 232 233 panic("exec returned"); 234 } 235 236 static int 237 elf64_obj_exec(struct preloaded_file *fp) 238 { 239 240 return (EFTYPE); 241 } 242