| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright IBM Corp. 2011 |
| * Author(s): Jan Glauber <jang@linux.vnet.ibm.com> |
| */ |
| #include <linux/hugetlb.h> |
| #include <linux/mm.h> |
| #include <asm/cacheflush.h> |
| #include <asm/facility.h> |
| #include <asm/pgalloc.h> |
| #include <asm/kfence.h> |
| #include <asm/page.h> |
| #include <asm/set_memory.h> |
| |
| 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 *)((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) |
| 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 */ |
