18f75582aSVasily Gorbik // SPDX-License-Identifier: GPL-2.0 28f75582aSVasily Gorbik #include <linux/string.h> 3805bc0bcSGerald Schaefer #include <linux/elf.h> 473045a08SVasily Gorbik #include <asm/boot_data.h> 5a80313ffSGerald Schaefer #include <asm/sections.h> 6d7e7fbbaSVasily Gorbik #include <asm/cpu_mf.h> 715426ca4SVasily Gorbik #include <asm/setup.h> 80c4f2623SVasily Gorbik #include <asm/kasan.h> 9805bc0bcSGerald Schaefer #include <asm/kexec.h> 107516fc11SVasily Gorbik #include <asm/sclp.h> 11a80313ffSGerald Schaefer #include <asm/diag.h> 125abb9351SVasily Gorbik #include <asm/uv.h> 13*edd4a866SHeiko Carstens #include "decompressor.h" 148f75582aSVasily Gorbik #include "boot.h" 15c5cf5054SAlexander Egorenkov #include "uv.h" 168f75582aSVasily Gorbik 17b2d24b97SGerald Schaefer unsigned long __bootdata_preserved(__kaslr_offset); 18e3ec8e0fSAlexander Gordeev unsigned long __bootdata(__amode31_base); 190c4f2623SVasily Gorbik unsigned long __bootdata_preserved(VMALLOC_START); 200c4f2623SVasily Gorbik unsigned long __bootdata_preserved(VMALLOC_END); 210c4f2623SVasily Gorbik struct page *__bootdata_preserved(vmemmap); 220c4f2623SVasily Gorbik unsigned long __bootdata_preserved(vmemmap_size); 230c4f2623SVasily Gorbik unsigned long __bootdata_preserved(MODULES_VADDR); 240c4f2623SVasily Gorbik unsigned long __bootdata_preserved(MODULES_END); 2573045a08SVasily Gorbik unsigned long __bootdata(ident_map_size); 269f744abbSAlexander Egorenkov int __bootdata(is_full_image) = 1; 2784733284SAlexander Egorenkov struct initrd_data __bootdata(initrd_data); 28d1b52a43SVasily Gorbik 2917e89e13SSven Schnelle u64 __bootdata_preserved(stfle_fac_list[16]); 3017e89e13SSven Schnelle u64 __bootdata_preserved(alt_stfle_fac_list[16]); 31e9e7870fSAlexander Egorenkov struct oldmem_data __bootdata_preserved(oldmem_data); 3217e89e13SSven Schnelle 337516fc11SVasily Gorbik void error(char *x) 347516fc11SVasily Gorbik { 357516fc11SVasily Gorbik sclp_early_printk("\n\n"); 367516fc11SVasily Gorbik sclp_early_printk(x); 377516fc11SVasily Gorbik sclp_early_printk("\n\n -- System halted"); 387516fc11SVasily Gorbik 3998587c2dSMartin Schwidefsky disabled_wait(); 407516fc11SVasily Gorbik } 417516fc11SVasily Gorbik 42d7e7fbbaSVasily Gorbik static void setup_lpp(void) 43d7e7fbbaSVasily Gorbik { 44d7e7fbbaSVasily Gorbik S390_lowcore.current_pid = 0; 45d7e7fbbaSVasily Gorbik S390_lowcore.lpp = LPP_MAGIC; 46d7e7fbbaSVasily Gorbik if (test_facility(40)) 47d7e7fbbaSVasily Gorbik lpp(&S390_lowcore.lpp); 48d7e7fbbaSVasily Gorbik } 49d7e7fbbaSVasily Gorbik 5015426ca4SVasily Gorbik #ifdef CONFIG_KERNEL_UNCOMPRESSED 5115426ca4SVasily Gorbik unsigned long mem_safe_offset(void) 5215426ca4SVasily Gorbik { 5315426ca4SVasily Gorbik return vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size; 5415426ca4SVasily Gorbik } 5515426ca4SVasily Gorbik #endif 5615426ca4SVasily Gorbik 579641b8ccSMartin Schwidefsky static void rescue_initrd(unsigned long addr) 5815426ca4SVasily Gorbik { 5915426ca4SVasily Gorbik if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD)) 6015426ca4SVasily Gorbik return; 6184733284SAlexander Egorenkov if (!initrd_data.start || !initrd_data.size) 6215426ca4SVasily Gorbik return; 6384733284SAlexander Egorenkov if (addr <= initrd_data.start) 6415426ca4SVasily Gorbik return; 6584733284SAlexander Egorenkov memmove((void *)addr, (void *)initrd_data.start, initrd_data.size); 6684733284SAlexander Egorenkov initrd_data.start = addr; 6715426ca4SVasily Gorbik } 6815426ca4SVasily Gorbik 69d1b52a43SVasily Gorbik static void copy_bootdata(void) 70d1b52a43SVasily Gorbik { 71d1b52a43SVasily Gorbik if (__boot_data_end - __boot_data_start != vmlinux.bootdata_size) 72d1b52a43SVasily Gorbik error(".boot.data section size mismatch"); 73d1b52a43SVasily Gorbik memcpy((void *)vmlinux.bootdata_off, __boot_data_start, vmlinux.bootdata_size); 74bf9921a9SGerald Schaefer if (__boot_data_preserved_end - __boot_data_preserved_start != vmlinux.bootdata_preserved_size) 75bf9921a9SGerald Schaefer error(".boot.preserved.data section size mismatch"); 76bf9921a9SGerald Schaefer memcpy((void *)vmlinux.bootdata_preserved_off, __boot_data_preserved_start, vmlinux.bootdata_preserved_size); 77d1b52a43SVasily Gorbik } 78d1b52a43SVasily Gorbik 79805bc0bcSGerald Schaefer static void handle_relocs(unsigned long offset) 80805bc0bcSGerald Schaefer { 81805bc0bcSGerald Schaefer Elf64_Rela *rela_start, *rela_end, *rela; 82805bc0bcSGerald Schaefer int r_type, r_sym, rc; 83805bc0bcSGerald Schaefer Elf64_Addr loc, val; 84805bc0bcSGerald Schaefer Elf64_Sym *dynsym; 85805bc0bcSGerald Schaefer 86805bc0bcSGerald Schaefer rela_start = (Elf64_Rela *) vmlinux.rela_dyn_start; 87805bc0bcSGerald Schaefer rela_end = (Elf64_Rela *) vmlinux.rela_dyn_end; 88805bc0bcSGerald Schaefer dynsym = (Elf64_Sym *) vmlinux.dynsym_start; 89805bc0bcSGerald Schaefer for (rela = rela_start; rela < rela_end; rela++) { 90805bc0bcSGerald Schaefer loc = rela->r_offset + offset; 91ac49303dSGerald Schaefer val = rela->r_addend; 92805bc0bcSGerald Schaefer r_sym = ELF64_R_SYM(rela->r_info); 93ac49303dSGerald Schaefer if (r_sym) { 94ac49303dSGerald Schaefer if (dynsym[r_sym].st_shndx != SHN_UNDEF) 95ac49303dSGerald Schaefer val += dynsym[r_sym].st_value + offset; 96ac49303dSGerald Schaefer } else { 97ac49303dSGerald Schaefer /* 98ac49303dSGerald Schaefer * 0 == undefined symbol table index (STN_UNDEF), 99ac49303dSGerald Schaefer * used for R_390_RELATIVE, only add KASLR offset 100ac49303dSGerald Schaefer */ 101ac49303dSGerald Schaefer val += offset; 102ac49303dSGerald Schaefer } 103805bc0bcSGerald Schaefer r_type = ELF64_R_TYPE(rela->r_info); 104805bc0bcSGerald Schaefer rc = arch_kexec_do_relocs(r_type, (void *) loc, val, 0); 105805bc0bcSGerald Schaefer if (rc) 106805bc0bcSGerald Schaefer error("Unknown relocation type"); 107805bc0bcSGerald Schaefer } 108805bc0bcSGerald Schaefer } 109805bc0bcSGerald Schaefer 110980d5f9aSAlexander Egorenkov /* 11173045a08SVasily Gorbik * Merge information from several sources into a single ident_map_size value. 11273045a08SVasily Gorbik * "ident_map_size" represents the upper limit of physical memory we may ever 11373045a08SVasily Gorbik * reach. It might not be all online memory, but also include standby (offline) 11473045a08SVasily Gorbik * memory. "ident_map_size" could be lower then actual standby or even online 11573045a08SVasily Gorbik * memory present, due to limiting factors. We should never go above this limit. 11673045a08SVasily Gorbik * It is the size of our identity mapping. 11773045a08SVasily Gorbik * 11873045a08SVasily Gorbik * Consider the following factors: 11973045a08SVasily Gorbik * 1. max_physmem_end - end of physical memory online or standby. 12073045a08SVasily Gorbik * Always <= end of the last online memory block (get_mem_detect_end()). 12173045a08SVasily Gorbik * 2. CONFIG_MAX_PHYSMEM_BITS - the maximum size of physical memory the 12273045a08SVasily Gorbik * kernel is able to support. 12373045a08SVasily Gorbik * 3. "mem=" kernel command line option which limits physical memory usage. 12473045a08SVasily Gorbik * 4. OLDMEM_BASE which is a kdump memory limit when the kernel is executed as 12573045a08SVasily Gorbik * crash kernel. 12673045a08SVasily Gorbik * 5. "hsa" size which is a memory limit when the kernel is executed during 12773045a08SVasily Gorbik * zfcp/nvme dump. 12873045a08SVasily Gorbik */ 12973045a08SVasily Gorbik static void setup_ident_map_size(unsigned long max_physmem_end) 13073045a08SVasily Gorbik { 13173045a08SVasily Gorbik unsigned long hsa_size; 13273045a08SVasily Gorbik 13373045a08SVasily Gorbik ident_map_size = max_physmem_end; 13473045a08SVasily Gorbik if (memory_limit) 13573045a08SVasily Gorbik ident_map_size = min(ident_map_size, memory_limit); 13673045a08SVasily Gorbik ident_map_size = min(ident_map_size, 1UL << MAX_PHYSMEM_BITS); 13773045a08SVasily Gorbik 13873045a08SVasily Gorbik #ifdef CONFIG_CRASH_DUMP 139e9e7870fSAlexander Egorenkov if (oldmem_data.start) { 14073045a08SVasily Gorbik kaslr_enabled = 0; 141e9e7870fSAlexander Egorenkov ident_map_size = min(ident_map_size, oldmem_data.size); 14273045a08SVasily Gorbik } else if (ipl_block_valid && is_ipl_block_dump()) { 14373045a08SVasily Gorbik kaslr_enabled = 0; 14473045a08SVasily Gorbik if (!sclp_early_get_hsa_size(&hsa_size) && hsa_size) 14573045a08SVasily Gorbik ident_map_size = min(ident_map_size, hsa_size); 14673045a08SVasily Gorbik } 14773045a08SVasily Gorbik #endif 14873045a08SVasily Gorbik } 14973045a08SVasily Gorbik 1500c4f2623SVasily Gorbik static void setup_kernel_memory_layout(void) 1510c4f2623SVasily Gorbik { 1529a39abb7SVasily Gorbik unsigned long vmemmap_start; 1530c4f2623SVasily Gorbik unsigned long rte_size; 1540c4f2623SVasily Gorbik unsigned long pages; 1550c4f2623SVasily Gorbik 1560c4f2623SVasily Gorbik pages = ident_map_size / PAGE_SIZE; 1570c4f2623SVasily Gorbik /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */ 1580c4f2623SVasily Gorbik vmemmap_size = SECTION_ALIGN_UP(pages) * sizeof(struct page); 1590c4f2623SVasily Gorbik 1600c4f2623SVasily Gorbik /* choose kernel address space layout: 4 or 3 levels. */ 1619a39abb7SVasily Gorbik vmemmap_start = round_up(ident_map_size, _REGION3_SIZE); 1620c4f2623SVasily Gorbik if (IS_ENABLED(CONFIG_KASAN) || 1630c4f2623SVasily Gorbik vmalloc_size > _REGION2_SIZE || 1649a39abb7SVasily Gorbik vmemmap_start + vmemmap_size + vmalloc_size + MODULES_LEN > 1659a39abb7SVasily Gorbik _REGION2_SIZE) { 1669a39abb7SVasily Gorbik MODULES_END = _REGION1_SIZE; 1679a39abb7SVasily Gorbik rte_size = _REGION2_SIZE; 1689a39abb7SVasily Gorbik } else { 1699a39abb7SVasily Gorbik MODULES_END = _REGION2_SIZE; 1709a39abb7SVasily Gorbik rte_size = _REGION3_SIZE; 1719a39abb7SVasily Gorbik } 1720c4f2623SVasily Gorbik /* 1730c4f2623SVasily Gorbik * forcing modules and vmalloc area under the ultravisor 1740c4f2623SVasily Gorbik * secure storage limit, so that any vmalloc allocation 1750c4f2623SVasily Gorbik * we do could be used to back secure guest storage. 1760c4f2623SVasily Gorbik */ 1770c4f2623SVasily Gorbik adjust_to_uv_max(&MODULES_END); 1780c4f2623SVasily Gorbik #ifdef CONFIG_KASAN 1790c4f2623SVasily Gorbik /* force vmalloc and modules below kasan shadow */ 1800c4f2623SVasily Gorbik MODULES_END = min(MODULES_END, KASAN_SHADOW_START); 1810c4f2623SVasily Gorbik #endif 1820c4f2623SVasily Gorbik MODULES_VADDR = MODULES_END - MODULES_LEN; 1830c4f2623SVasily Gorbik VMALLOC_END = MODULES_VADDR; 1840c4f2623SVasily Gorbik 1859a39abb7SVasily Gorbik /* allow vmalloc area to occupy up to about 1/2 of the rest virtual space left */ 1869a39abb7SVasily Gorbik vmalloc_size = min(vmalloc_size, round_down(VMALLOC_END / 2, _REGION3_SIZE)); 1870c4f2623SVasily Gorbik VMALLOC_START = VMALLOC_END - vmalloc_size; 1880c4f2623SVasily Gorbik 1899a39abb7SVasily Gorbik /* split remaining virtual space between 1:1 mapping & vmemmap array */ 1909a39abb7SVasily Gorbik pages = VMALLOC_START / (PAGE_SIZE + sizeof(struct page)); 1910c4f2623SVasily Gorbik pages = SECTION_ALIGN_UP(pages); 1929a39abb7SVasily Gorbik /* keep vmemmap_start aligned to a top level region table entry */ 1939a39abb7SVasily Gorbik vmemmap_start = round_down(VMALLOC_START - pages * sizeof(struct page), rte_size); 1949a39abb7SVasily Gorbik /* vmemmap_start is the future VMEM_MAX_PHYS, make sure it is within MAX_PHYSMEM */ 1959a39abb7SVasily Gorbik vmemmap_start = min(vmemmap_start, 1UL << MAX_PHYSMEM_BITS); 1969a39abb7SVasily Gorbik /* make sure identity map doesn't overlay with vmemmap */ 1979a39abb7SVasily Gorbik ident_map_size = min(ident_map_size, vmemmap_start); 1980c4f2623SVasily Gorbik vmemmap_size = SECTION_ALIGN_UP(ident_map_size / PAGE_SIZE) * sizeof(struct page); 1999a39abb7SVasily Gorbik /* make sure vmemmap doesn't overlay with vmalloc area */ 2009a39abb7SVasily Gorbik VMALLOC_START = max(vmemmap_start + vmemmap_size, VMALLOC_START); 2019a39abb7SVasily Gorbik vmemmap = (struct page *)vmemmap_start; 2020c4f2623SVasily Gorbik } 2030c4f2623SVasily Gorbik 20473045a08SVasily Gorbik /* 205980d5f9aSAlexander Egorenkov * This function clears the BSS section of the decompressed Linux kernel and NOT the decompressor's. 206980d5f9aSAlexander Egorenkov */ 2072e83e0ebSVasily Gorbik static void clear_bss_section(void) 2082e83e0ebSVasily Gorbik { 2092e83e0ebSVasily Gorbik memset((void *)vmlinux.default_lma + vmlinux.image_size, 0, vmlinux.bss_size); 2102e83e0ebSVasily Gorbik } 2112e83e0ebSVasily Gorbik 21290178c19SHeiko Carstens /* 21390178c19SHeiko Carstens * Set vmalloc area size to an 8th of (potential) physical memory 21490178c19SHeiko Carstens * size, unless size has been set by kernel command line parameter. 21590178c19SHeiko Carstens */ 21690178c19SHeiko Carstens static void setup_vmalloc_size(void) 21790178c19SHeiko Carstens { 21890178c19SHeiko Carstens unsigned long size; 21990178c19SHeiko Carstens 22090178c19SHeiko Carstens if (vmalloc_size_set) 22190178c19SHeiko Carstens return; 22273045a08SVasily Gorbik size = round_up(ident_map_size / 8, _SEGMENT_SIZE); 22390178c19SHeiko Carstens vmalloc_size = max(size, vmalloc_size); 22490178c19SHeiko Carstens } 22590178c19SHeiko Carstens 226e8f06683SAlexander Gordeev static void offset_vmlinux_info(unsigned long offset) 227e8f06683SAlexander Gordeev { 228e8f06683SAlexander Gordeev vmlinux.default_lma += offset; 229e8f06683SAlexander Gordeev *(unsigned long *)(&vmlinux.entry) += offset; 230e8f06683SAlexander Gordeev vmlinux.bootdata_off += offset; 231e8f06683SAlexander Gordeev vmlinux.bootdata_preserved_off += offset; 232e8f06683SAlexander Gordeev vmlinux.rela_dyn_start += offset; 233e8f06683SAlexander Gordeev vmlinux.rela_dyn_end += offset; 234e8f06683SAlexander Gordeev vmlinux.dynsym_start += offset; 235e8f06683SAlexander Gordeev } 236e8f06683SAlexander Gordeev 237e3ec8e0fSAlexander Gordeev static unsigned long reserve_amode31(unsigned long safe_addr) 238e3ec8e0fSAlexander Gordeev { 239e3ec8e0fSAlexander Gordeev __amode31_base = PAGE_ALIGN(safe_addr); 240e3ec8e0fSAlexander Gordeev return safe_addr + vmlinux.amode31_size; 241e3ec8e0fSAlexander Gordeev } 242e3ec8e0fSAlexander Gordeev 2438f75582aSVasily Gorbik void startup_kernel(void) 2448f75582aSVasily Gorbik { 245b2d24b97SGerald Schaefer unsigned long random_lma; 2469641b8ccSMartin Schwidefsky unsigned long safe_addr; 247369f91c3SVasily Gorbik void *img; 2488f75582aSVasily Gorbik 24984733284SAlexander Egorenkov initrd_data.start = parmarea.initrd_start; 25084733284SAlexander Egorenkov initrd_data.size = parmarea.initrd_size; 251e9e7870fSAlexander Egorenkov oldmem_data.start = parmarea.oldmem_base; 252e9e7870fSAlexander Egorenkov oldmem_data.size = parmarea.oldmem_size; 25384733284SAlexander Egorenkov 254d7e7fbbaSVasily Gorbik setup_lpp(); 25549698745SVasily Gorbik store_ipl_parmblock(); 2569641b8ccSMartin Schwidefsky safe_addr = mem_safe_offset(); 257e3ec8e0fSAlexander Gordeev safe_addr = reserve_amode31(safe_addr); 2589641b8ccSMartin Schwidefsky safe_addr = read_ipl_report(safe_addr); 2599641b8ccSMartin Schwidefsky uv_query_info(); 2609641b8ccSMartin Schwidefsky rescue_initrd(safe_addr); 2619641b8ccSMartin Schwidefsky sclp_early_read_info(); 26249698745SVasily Gorbik setup_boot_command_line(); 263b5e80459SVasily Gorbik parse_boot_command_line(); 26442c89439SAlexander Egorenkov sanitize_prot_virt_host(); 26573045a08SVasily Gorbik setup_ident_map_size(detect_memory()); 26690178c19SHeiko Carstens setup_vmalloc_size(); 2670c4f2623SVasily Gorbik setup_kernel_memory_layout(); 268b2d24b97SGerald Schaefer 269b2d24b97SGerald Schaefer if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_enabled) { 270b2d24b97SGerald Schaefer random_lma = get_random_base(safe_addr); 271b2d24b97SGerald Schaefer if (random_lma) { 272b2d24b97SGerald Schaefer __kaslr_offset = random_lma - vmlinux.default_lma; 273b2d24b97SGerald Schaefer img = (void *)vmlinux.default_lma; 274e8f06683SAlexander Gordeev offset_vmlinux_info(__kaslr_offset); 275b2d24b97SGerald Schaefer } 276b2d24b97SGerald Schaefer } 277b2d24b97SGerald Schaefer 2788f75582aSVasily Gorbik if (!IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED)) { 279369f91c3SVasily Gorbik img = decompress_kernel(); 280369f91c3SVasily Gorbik memmove((void *)vmlinux.default_lma, img, vmlinux.image_size); 281b2d24b97SGerald Schaefer } else if (__kaslr_offset) 282b2d24b97SGerald Schaefer memcpy((void *)vmlinux.default_lma, img, vmlinux.image_size); 283b2d24b97SGerald Schaefer 2842e83e0ebSVasily Gorbik clear_bss_section(); 285d1b52a43SVasily Gorbik copy_bootdata(); 286805bc0bcSGerald Schaefer if (IS_ENABLED(CONFIG_RELOCATABLE)) 287b2d24b97SGerald Schaefer handle_relocs(__kaslr_offset); 288b2d24b97SGerald Schaefer 289b2d24b97SGerald Schaefer if (__kaslr_offset) { 290a9f2f686SGerald Schaefer /* 291a9f2f686SGerald Schaefer * Save KASLR offset for early dumps, before vmcore_info is set. 292a9f2f686SGerald Schaefer * Mark as uneven to distinguish from real vmcore_info pointer. 293a9f2f686SGerald Schaefer */ 294a9f2f686SGerald Schaefer S390_lowcore.vmcore_info = __kaslr_offset | 0x1UL; 295b2d24b97SGerald Schaefer /* Clear non-relocated kernel */ 296b2d24b97SGerald Schaefer if (IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED)) 297b2d24b97SGerald Schaefer memset(img, 0, vmlinux.image_size); 298b2d24b97SGerald Schaefer } 299369f91c3SVasily Gorbik vmlinux.entry(); 3008f75582aSVasily Gorbik } 301