1 files changed, 402 insertions, 73 deletions

diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
index 80adfbf75065..3042647c9dbf 100644
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -1,27 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright IBM Corp. 2011
  * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
  */
+#include <linux/cpufeature.h>
 #include <linux/hugetlb.h>
-#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <asm/cacheflush.h>
-#include <asm/pgtable.h>
+#include <asm/facility.h>
+#include <asm/pgalloc.h>
+#include <asm/kfence.h>
 #include <asm/page.h>
+#include <asm/asm.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],9,0"
+	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)
+void __storage_key_init_range(unsigned long start, unsigned long end)
 {
 	unsigned long boundary, size;
 
 	while (start < end) {
-		if (MACHINE_HAS_EDAT1) {
+		if (cpu_has_edat1()) {
 			/* set storage keys for a 1MB frame */
 			size = 1UL << 20;
 			boundary = (start + size) & ~(size - 1);
@@ -32,113 +39,435 @@ void storage_key_init_range(unsigned long start, unsigned long end)
 				continue;
 			}
 		}
-		page_set_storage_key(start, PAGE_DEFAULT_KEY, 0);
+		page_set_storage_key(start, PAGE_DEFAULT_KEY, 1);
 		start += PAGE_SIZE;
 	}
 }
 
-static pte_t *walk_page_table(unsigned long addr)
-{
-	pgd_t *pgdp;
-	pud_t *pudp;
-	pmd_t *pmdp;
-	pte_t *ptep;
+#ifdef CONFIG_PROC_FS
+atomic_long_t __bootdata_preserved(direct_pages_count[PG_DIRECT_MAP_MAX]);
 
-	pgdp = pgd_offset_k(addr);
-	if (pgd_none(*pgdp))
-		return NULL;
-	pudp = pud_offset(pgdp, addr);
-	if (pud_none(*pudp) || pud_large(*pudp))
-		return NULL;
-	pmdp = pmd_offset(pudp, addr);
-	if (pmd_none(*pmdp) || pmd_large(*pmdp))
-		return NULL;
-	ptep = pte_offset_kernel(pmdp, addr);
-	if (pte_none(*ptep))
-		return NULL;
-	return ptep;
+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 change_page_attr(unsigned long addr, int numpages,
-			     pte_t (*set) (pte_t))
+static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
+		    unsigned long dtt)
 {
-	pte_t *ptep, pte;
-	int i;
+	unsigned long *table, mask;
 
-	for (i = 0; i < numpages; i++) {
-		ptep = walk_page_table(addr);
-		if (WARN_ON_ONCE(!ptep))
+	mask = 0;
+	if (cpu_has_edat2()) {
+		switch (dtt) {
+		case CRDTE_DTT_REGION3:
+			mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
 			break;
-		pte = *ptep;
-		pte = set(pte);
-		__ptep_ipte(addr, ptep);
-		*ptep = pte;
-		addr += PAGE_SIZE;
+		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, get_lowcore()->kernel_asce.val);
+	} else {
+		cspg(old, *old, new);
 	}
 }
 
-int set_memory_ro(unsigned long addr, int numpages)
+static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
+			  unsigned long flags)
 {
-	change_page_attr(addr, numpages, pte_wrprotect);
+	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_novma(pte_mkdirty(new));
+		if (flags & SET_MEMORY_NX)
+			new = set_pte_bit(new, __pgprot(_PAGE_NOEXEC));
+		else if (flags & SET_MEMORY_X)
+			new = clear_pte_bit(new, __pgprot(_PAGE_NOEXEC));
+		if (flags & SET_MEMORY_INV) {
+			new = set_pte_bit(new, __pgprot(_PAGE_INVALID));
+		} else if (flags & SET_MEMORY_DEF) {
+			new = __pte(pte_val(new) & PAGE_MASK);
+			new = set_pte_bit(new, PAGE_KERNEL);
+		}
+		pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
+		ptep++;
+		addr += PAGE_SIZE;
+		cond_resched();
+	} while (addr < end);
 	return 0;
 }
 
-int set_memory_rw(unsigned long addr, int numpages)
+static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
 {
-	change_page_attr(addr, numpages, pte_mkwrite);
+	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++) {
+		set_pte(ptep, __pte(pte_addr | prot));
+		pte_addr += PAGE_SIZE;
+		ptep++;
+	}
+	new = __pmd(__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;
 }
 
-/* not possible */
-int set_memory_nx(unsigned long addr, int numpages)
+static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
+			    unsigned long flags)
 {
-	return 0;
+	pmd_t new = *pmdp;
+
+	if (flags & SET_MEMORY_RO)
+		new = pmd_wrprotect(new);
+	else if (flags & SET_MEMORY_RW)
+		new = pmd_mkwrite_novma(pmd_mkdirty(new));
+	if (flags & SET_MEMORY_NX)
+		new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
+	else if (flags & SET_MEMORY_X)
+		new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
+	if (flags & SET_MEMORY_INV) {
+		new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_INVALID));
+	} else if (flags & SET_MEMORY_DEF) {
+		new = __pmd(pmd_val(new) & PMD_MASK);
+		new = set_pmd_bit(new, SEGMENT_KERNEL);
+	}
+	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_leaf(*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;
 }
 
-int set_memory_x(unsigned long addr, int numpages)
+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++) {
+		set_pmd(pmdp, __pmd(pmd_addr | prot));
+		pmd_addr += PMD_SIZE;
+		pmdp++;
+	}
+	new = __pud(__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;
 }
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-void kernel_map_pages(struct page *page, int numpages, int enable)
+static void modify_pud_page(pud_t *pudp, unsigned long addr,
+			    unsigned long flags)
 {
-	unsigned long address;
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	pte_t *pte;
-	int i;
+	pud_t new = *pudp;
 
-	for (i = 0; i < numpages; i++) {
-		address = page_to_phys(page + i);
-		pgd = pgd_offset_k(address);
-		pud = pud_offset(pgd, address);
-		pmd = pmd_offset(pud, address);
-		pte = pte_offset_kernel(pmd, address);
-		if (!enable) {
-			__ptep_ipte(address, pte);
-			pte_val(*pte) = _PAGE_TYPE_EMPTY;
-			continue;
+	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)
+		new = set_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
+	else if (flags & SET_MEMORY_X)
+		new = clear_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
+	if (flags & SET_MEMORY_INV) {
+		new = set_pud_bit(new, __pgprot(_REGION_ENTRY_INVALID));
+	} else if (flags & SET_MEMORY_DEF) {
+		new = __pud(pud_val(new) & PUD_MASK);
+		new = set_pud_bit(new, REGION3_KERNEL);
+	}
+	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_leaf(*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);
 		}
-		pte_val(*pte) = __pa(address);
+		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;
+
+	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);
+	return rc;
+}
+
+static int change_page_attr_alias(unsigned long addr, unsigned long end,
+				  unsigned long flags)
+{
+	unsigned long alias, offset, va_start, va_end;
+	struct vm_struct *area;
+	int rc = 0;
+
+	/*
+	 * Changes to read-only permissions on kernel VA mappings are also
+	 * applied to the kernel direct mapping. Execute permissions are
+	 * intentionally not transferred to keep all allocated pages within
+	 * the direct mapping non-executable.
+	 */
+	flags &= SET_MEMORY_RO | SET_MEMORY_RW;
+	if (!flags)
+		return 0;
+	area = NULL;
+	while (addr < end) {
+		if (!area)
+			area = find_vm_area((void *)addr);
+		if (!area || !(area->flags & VM_ALLOC))
+			return 0;
+		va_start = (unsigned long)area->addr;
+		va_end = va_start + area->nr_pages * PAGE_SIZE;
+		offset = (addr - va_start) >> PAGE_SHIFT;
+		alias = (unsigned long)page_address(area->pages[offset]);
+		rc = change_page_attr(alias, alias + PAGE_SIZE, flags);
+		if (rc)
+			break;
+		addr += PAGE_SIZE;
+		if (addr >= va_end)
+			area = NULL;
 	}
+	return rc;
+}
+
+int __set_memory(unsigned long addr, unsigned long numpages, unsigned long flags)
+{
+	unsigned long end;
+	int rc;
+
+	if (!cpu_has_nx())
+		flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
+	if (!flags)
+		return 0;
+	if (!numpages)
+		return 0;
+	addr &= PAGE_MASK;
+	end = addr + numpages * PAGE_SIZE;
+	mutex_lock(&cpa_mutex);
+	rc = change_page_attr(addr, end, flags);
+	if (rc)
+		goto out;
+	rc = change_page_attr_alias(addr, end, flags);
+out:
+	mutex_unlock(&cpa_mutex);
+	return rc;
+}
+
+int set_direct_map_invalid_noflush(struct page *page)
+{
+	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_INV);
+}
+
+int set_direct_map_default_noflush(struct page *page)
+{
+	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_DEF);
+}
+
+int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
+{
+	unsigned long flags;
+
+	if (valid)
+		flags = SET_MEMORY_DEF;
+	else
+		flags = SET_MEMORY_INV;
+
+	return __set_memory((unsigned long)page_to_virt(page), nr, flags);
 }
 
-#ifdef CONFIG_HIBERNATION
 bool kernel_page_present(struct page *page)
 {
 	unsigned long addr;
-	int cc;
+	unsigned int cc;
 
-	addr = page_to_phys(page);
+	addr = (unsigned long)page_address(page);
 	asm volatile(
-		"	lra	%1,0(%1)\n"
-		"	ipm	%0\n"
-		"	srl	%0,28"
-		: "=d" (cc), "+a" (addr) : : "cc");
-	return cc == 0;
+		"	lra	%[addr],0(%[addr])\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, cc), [addr] "+a" (addr)
+		:
+		: CC_CLOBBER);
+	return CC_TRANSFORM(cc) == 0;
+}
+
+#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;
+	pte_t *ptep, pte;
+	int nr, i, j;
+
+	for (i = 0; i < numpages;) {
+		address = (unsigned long)page_to_virt(page + i);
+		ptep = virt_to_kpte(address);
+		nr = (unsigned long)ptep >> 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 = clear_pte_bit(*ptep, __pgprot(_PAGE_INVALID));
+				set_pte(ptep, pte);
+				address += PAGE_SIZE;
+				ptep++;
+			}
+		} else {
+			ipte_range(ptep, address, nr);
+		}
+		i += nr;
+	}
 }
-#endif /* CONFIG_HIBERNATION */
 
 #endif /* CONFIG_DEBUG_PAGEALLOC */