// SPDX-License-Identifier: GPL-2.0 /* * Copyright IBM Corp. 2011 * Author(s): Jan Glauber */ #include #include #include #include #include #include #include #include static inline unsigned long sske_frame(unsigned long addr, unsigned char skey) { asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],1,0" : [addr] "+a" (addr) : [skey] "d" (skey)); return addr; } void __storage_key_init_range(unsigned long start, unsigned long end) { unsigned long boundary, size; while (start < end) { if (MACHINE_HAS_EDAT1) { /* set storage keys for a 1MB frame */ size = 1UL << 20; boundary = (start + size) & ~(size - 1); if (boundary <= end) { do { start = sske_frame(start, PAGE_DEFAULT_KEY); } while (start < boundary); continue; } } page_set_storage_key(start, PAGE_DEFAULT_KEY, 1); start += PAGE_SIZE; } } #ifdef CONFIG_PROC_FS atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX]; void arch_report_meminfo(struct seq_file *m) { seq_printf(m, "DirectMap4k: %8lu kB\n", atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2); seq_printf(m, "DirectMap1M: %8lu kB\n", atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10); seq_printf(m, "DirectMap2G: %8lu kB\n", atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21); } #endif /* CONFIG_PROC_FS */ static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr, unsigned long dtt) { unsigned long table, mask; mask = 0; if (MACHINE_HAS_EDAT2) { switch (dtt) { case CRDTE_DTT_REGION3: mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1); break; case CRDTE_DTT_SEGMENT: mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); break; case CRDTE_DTT_PAGE: mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1); break; } table = (unsigned long)old & mask; crdte(*old, new, table, dtt, addr, S390_lowcore.kernel_asce); } else if (MACHINE_HAS_IDTE) { cspg(old, *old, new); } else { csp((unsigned int *)old + 1, *old, new); } } static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end, unsigned long flags) { pte_t *ptep, new; if ((flags & SET_MEMORY_4K) == SET_MEMORY_4K) return 0; ptep = pte_offset_kernel(pmdp, addr); do { new = *ptep; if (pte_none(new)) return -EINVAL; if (flags & SET_MEMORY_RO) new = pte_wrprotect(new); else if (flags & SET_MEMORY_RW) new = pte_mkwrite(pte_mkdirty(new)); if (flags & SET_MEMORY_NX) pte_val(new) |= _PAGE_NOEXEC; else if (flags & SET_MEMORY_X) pte_val(new) &= ~_PAGE_NOEXEC; pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE); ptep++; addr += PAGE_SIZE; cond_resched(); } while (addr < end); return 0; } static int split_pmd_page(pmd_t *pmdp, unsigned long addr) { unsigned long pte_addr, prot; pte_t *pt_dir, *ptep; pmd_t new; int i, ro, nx; pt_dir = vmem_pte_alloc(); if (!pt_dir) return -ENOMEM; pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT; ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT); nx = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_NOEXEC); prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL); if (!nx) prot &= ~_PAGE_NOEXEC; ptep = pt_dir; for (i = 0; i < PTRS_PER_PTE; i++) { pte_val(*ptep) = pte_addr | prot; pte_addr += PAGE_SIZE; ptep++; } pmd_val(new) = __pa(pt_dir) | _SEGMENT_ENTRY; pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT); update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE); update_page_count(PG_DIRECT_MAP_1M, -1); return 0; } static void modify_pmd_page(pmd_t *pmdp, unsigned long addr, unsigned long flags) { pmd_t new = *pmdp; if (flags & SET_MEMORY_RO) new = pmd_wrprotect(new); else if (flags & SET_MEMORY_RW) new = pmd_mkwrite(pmd_mkdirty(new)); if (flags & SET_MEMORY_NX) pmd_val(new) |= _SEGMENT_ENTRY_NOEXEC; else if (flags & SET_MEMORY_X) pmd_val(new) &= ~_SEGMENT_ENTRY_NOEXEC; pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT); } static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end, unsigned long flags) { unsigned long next; int need_split; pmd_t *pmdp; int rc = 0; pmdp = pmd_offset(pudp, addr); do { if (pmd_none(*pmdp)) return -EINVAL; next = pmd_addr_end(addr, end); if (pmd_large(*pmdp)) { need_split = !!(flags & SET_MEMORY_4K); need_split |= !!(addr & ~PMD_MASK); need_split |= !!(addr + PMD_SIZE > next); if (need_split) { rc = split_pmd_page(pmdp, addr); if (rc) return rc; continue; } modify_pmd_page(pmdp, addr, flags); } else { rc = walk_pte_level(pmdp, addr, next, flags); if (rc) return rc; } pmdp++; addr = next; cond_resched(); } while (addr < end); return rc; } static int split_pud_page(pud_t *pudp, unsigned long addr) { unsigned long pmd_addr, prot; pmd_t *pm_dir, *pmdp; pud_t new; int i, ro, nx; pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY); if (!pm_dir) return -ENOMEM; pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT; ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT); nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC); prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL); if (!nx) prot &= ~_SEGMENT_ENTRY_NOEXEC; pmdp = pm_dir; for (i = 0; i < PTRS_PER_PMD; i++) { pmd_val(*pmdp) = pmd_addr | prot; pmd_addr += PMD_SIZE; pmdp++; } pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY; pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3); update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD); update_page_count(PG_DIRECT_MAP_2G, -1); return 0; } static void modify_pud_page(pud_t *pudp, unsigned long addr, unsigned long flags) { pud_t new = *pudp; if (flags & SET_MEMORY_RO) new = pud_wrprotect(new); else if (flags & SET_MEMORY_RW) new = pud_mkwrite(pud_mkdirty(new)); if (flags & SET_MEMORY_NX) pud_val(new) |= _REGION_ENTRY_NOEXEC; else if (flags & SET_MEMORY_X) pud_val(new) &= ~_REGION_ENTRY_NOEXEC; pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3); } static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end, unsigned long flags) { unsigned long next; int need_split; pud_t *pudp; int rc = 0; pudp = pud_offset(p4d, addr); do { if (pud_none(*pudp)) return -EINVAL; next = pud_addr_end(addr, end); if (pud_large(*pudp)) { need_split = !!(flags & SET_MEMORY_4K); need_split |= !!(addr & ~PUD_MASK); need_split |= !!(addr + PUD_SIZE > next); if (need_split) { rc = split_pud_page(pudp, addr); if (rc) break; continue; } modify_pud_page(pudp, addr, flags); } else { rc = walk_pmd_level(pudp, addr, next, flags); } pudp++; addr = next; cond_resched(); } while (addr < end && !rc); return rc; } static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end, unsigned long flags) { unsigned long next; p4d_t *p4dp; int rc = 0; p4dp = p4d_offset(pgd, addr); do { if (p4d_none(*p4dp)) return -EINVAL; next = p4d_addr_end(addr, end); rc = walk_pud_level(p4dp, addr, next, flags); p4dp++; addr = next; cond_resched(); } while (addr < end && !rc); return rc; } DEFINE_MUTEX(cpa_mutex); static int change_page_attr(unsigned long addr, unsigned long end, unsigned long flags) { unsigned long next; int rc = -EINVAL; pgd_t *pgdp; if (addr == end) return 0; if (end >= MODULES_END) return -EINVAL; mutex_lock(&cpa_mutex); pgdp = pgd_offset_k(addr); do { if (pgd_none(*pgdp)) break; next = pgd_addr_end(addr, end); rc = walk_p4d_level(pgdp, addr, next, flags); if (rc) break; cond_resched(); } while (pgdp++, addr = next, addr < end && !rc); mutex_unlock(&cpa_mutex); return rc; } int __set_memory(unsigned long addr, int numpages, unsigned long flags) { if (!MACHINE_HAS_NX) flags &= ~(SET_MEMORY_NX | SET_MEMORY_X); if (!flags) return 0; addr &= PAGE_MASK; return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags); } #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE) static void ipte_range(pte_t *pte, unsigned long address, int nr) { int i; if (test_facility(13)) { __ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL); return; } for (i = 0; i < nr; i++) { __ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL); address += PAGE_SIZE; pte++; } } void __kernel_map_pages(struct page *page, int numpages, int enable) { unsigned long address; int nr, i, j; pte_t *pte; for (i = 0; i < numpages;) { address = (unsigned long)page_to_virt(page + i); pte = virt_to_kpte(address); nr = (unsigned long)pte >> ilog2(sizeof(long)); nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1)); nr = min(numpages - i, nr); if (enable) { for (j = 0; j < nr; j++) { pte_val(*pte) &= ~_PAGE_INVALID; address += PAGE_SIZE; pte++; } } else { ipte_range(pte, address, nr); } i += nr; } } #endif /* CONFIG_DEBUG_PAGEALLOC */