Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 386 insertions, 0 deletions

diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
new file mode 100644
index 000000000..f8c6faab4
--- /dev/null
+++ b/arch/s390/mm/pageattr.c
@@ -0,0 +1,386 @@
+// 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/pgtable.h>
+#include <asm/pgalloc.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)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;
+
+	ptep = pte_offset(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;
+	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)) {
+			if (addr & ~PMD_MASK || addr + PMD_SIZE > next) {
+				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;
+	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)) {
+			if (addr & ~PUD_MASK || addr + PUD_SIZE > next) {
+				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;
+}
+
+static 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);
+}
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+
+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;
+	pgd_t *pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+
+	for (i = 0; i < numpages;) {
+		address = page_to_phys(page + i);
+		pgd = pgd_offset_k(address);
+		p4d = p4d_offset(pgd, address);
+		pud = pud_offset(p4d, address);
+		pmd = pmd_offset(pud, address);
+		pte = pte_offset_kernel(pmd, 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;
+	}
+}
+
+#ifdef CONFIG_HIBERNATION
+bool kernel_page_present(struct page *page)
+{
+	unsigned long addr;
+	int cc;
+
+	addr = page_to_phys(page);
+	asm volatile(
+		"	lra	%1,0(%1)\n"
+		"	ipm	%0\n"
+		"	srl	%0,28"
+		: "=d" (cc), "+a" (addr) : : "cc");
+	return cc == 0;
+}
+#endif /* CONFIG_HIBERNATION */
+
+#endif /* CONFIG_DEBUG_PAGEALLOC */