1 files changed, 111 insertions, 236 deletions

diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index 781965f7210e..7df23528c01b 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -10,70 +10,45 @@
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <asm/mmu_context.h>
+#include <asm/page-states.h>
 #include <asm/pgalloc.h>
-#include <asm/gmap.h>
-#include <asm/tlb.h>
 #include <asm/tlbflush.h>
 
-#ifdef CONFIG_PGSTE
-
-int page_table_allocate_pgste = 0;
-EXPORT_SYMBOL(page_table_allocate_pgste);
-
-static struct ctl_table page_table_sysctl[] = {
-	{
-		.procname	= "allocate_pgste",
-		.data		= &page_table_allocate_pgste,
-		.maxlen		= sizeof(int),
-		.mode		= S_IRUGO | S_IWUSR,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_ONE,
-	},
-	{ }
-};
-
-static struct ctl_table page_table_sysctl_dir[] = {
-	{
-		.procname	= "vm",
-		.maxlen		= 0,
-		.mode		= 0555,
-		.child		= page_table_sysctl,
-	},
-	{ }
-};
-
-static int __init page_table_register_sysctl(void)
+unsigned long *crst_table_alloc_noprof(struct mm_struct *mm)
 {
-	return register_sysctl_table(page_table_sysctl_dir) ? 0 : -ENOMEM;
-}
-__initcall(page_table_register_sysctl);
-
-#endif /* CONFIG_PGSTE */
-
-unsigned long *crst_table_alloc(struct mm_struct *mm)
-{
-	struct page *page = alloc_pages(GFP_KERNEL, 2);
+	gfp_t gfp = GFP_KERNEL_ACCOUNT;
+	struct ptdesc *ptdesc;
+	unsigned long *table;
 
-	if (!page)
+	if (mm == &init_mm)
+		gfp &= ~__GFP_ACCOUNT;
+	ptdesc = pagetable_alloc_noprof(gfp, CRST_ALLOC_ORDER);
+	if (!ptdesc)
 		return NULL;
-	arch_set_page_dat(page, 2);
-	return (unsigned long *) page_to_virt(page);
+	table = ptdesc_address(ptdesc);
+	__arch_set_page_dat(table, 1UL << CRST_ALLOC_ORDER);
+	return table;
 }
 
 void crst_table_free(struct mm_struct *mm, unsigned long *table)
 {
-	free_pages((unsigned long) table, 2);
+	if (!table)
+		return;
+	pagetable_free(virt_to_ptdesc(table));
 }
 
 static void __crst_table_upgrade(void *arg)
 {
 	struct mm_struct *mm = arg;
+	struct ctlreg asce;
 
 	/* change all active ASCEs to avoid the creation of new TLBs */
 	if (current->active_mm == mm) {
-		S390_lowcore.user_asce = mm->context.asce;
-		__ctl_load(S390_lowcore.user_asce, 7, 7);
+		asce.val = mm->context.asce;
+		get_lowcore()->user_asce = asce;
+		local_ctl_load(7, &asce);
+		if (!test_thread_flag(TIF_ASCE_PRIMARY))
+			local_ctl_load(1, &asce);
 	}
 	__tlb_flush_local();
 }
@@ -83,6 +58,8 @@ int crst_table_upgrade(struct mm_struct *mm, unsigned long end)
 	unsigned long *pgd = NULL, *p4d = NULL, *__pgd;
 	unsigned long asce_limit = mm->context.asce_limit;
 
+	mmap_assert_write_locked(mm);
+
 	/* upgrade should only happen from 3 to 4, 3 to 5, or 4 to 5 levels */
 	VM_BUG_ON(asce_limit < _REGION2_SIZE);
 
@@ -94,23 +71,18 @@ int crst_table_upgrade(struct mm_struct *mm, unsigned long end)
 		if (unlikely(!p4d))
 			goto err_p4d;
 		crst_table_init(p4d, _REGION2_ENTRY_EMPTY);
+		pagetable_p4d_ctor(virt_to_ptdesc(p4d));
 	}
 	if (end > _REGION1_SIZE) {
 		pgd = crst_table_alloc(mm);
 		if (unlikely(!pgd))
 			goto err_pgd;
 		crst_table_init(pgd, _REGION1_ENTRY_EMPTY);
+		pagetable_pgd_ctor(virt_to_ptdesc(pgd));
 	}
 
 	spin_lock_bh(&mm->page_table_lock);
 
-	/*
-	 * This routine gets called with mmap_lock lock held and there is
-	 * no reason to optimize for the case of otherwise. However, if
-	 * that would ever change, the below check will let us know.
-	 */
-	VM_BUG_ON(asce_limit != mm->context.asce_limit);
-
 	if (p4d) {
 		__pgd = (unsigned long *) mm->pgd;
 		p4d_populate(mm, (p4d_t *) p4d, (pud_t *) __pgd);
@@ -136,184 +108,82 @@ int crst_table_upgrade(struct mm_struct *mm, unsigned long end)
 	return 0;
 
 err_pgd:
+	pagetable_dtor(virt_to_ptdesc(p4d));
 	crst_table_free(mm, p4d);
 err_p4d:
 	return -ENOMEM;
 }
 
-static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
-{
-	unsigned int old, new;
-
-	do {
-		old = atomic_read(v);
-		new = old ^ bits;
-	} while (atomic_cmpxchg(v, old, new) != old);
-	return new;
-}
-
 #ifdef CONFIG_PGSTE
 
-struct page *page_table_alloc_pgste(struct mm_struct *mm)
+struct ptdesc *page_table_alloc_pgste_noprof(struct mm_struct *mm)
 {
-	struct page *page;
+	struct ptdesc *ptdesc;
 	u64 *table;
 
-	page = alloc_page(GFP_KERNEL);
-	if (page) {
-		table = (u64 *)page_to_virt(page);
+	ptdesc = pagetable_alloc_noprof(GFP_KERNEL_ACCOUNT, 0);
+	if (ptdesc) {
+		table = (u64 *)ptdesc_address(ptdesc);
+		__arch_set_page_dat(table, 1);
 		memset64(table, _PAGE_INVALID, PTRS_PER_PTE);
 		memset64(table + PTRS_PER_PTE, 0, PTRS_PER_PTE);
 	}
-	return page;
+	return ptdesc;
 }
 
-void page_table_free_pgste(struct page *page)
+void page_table_free_pgste(struct ptdesc *ptdesc)
 {
-	__free_page(page);
+	pagetable_free(ptdesc);
 }
 
 #endif /* CONFIG_PGSTE */
 
-/*
- * page table entry allocation/free routines.
- */
-unsigned long *page_table_alloc(struct mm_struct *mm)
+unsigned long *page_table_alloc_noprof(struct mm_struct *mm)
 {
+	gfp_t gfp = GFP_KERNEL_ACCOUNT;
+	struct ptdesc *ptdesc;
 	unsigned long *table;
-	struct page *page;
-	unsigned int mask, bit;
-
-	/* Try to get a fragment of a 4K page as a 2K page table */
-	if (!mm_alloc_pgste(mm)) {
-		table = NULL;
-		spin_lock_bh(&mm->context.lock);
-		if (!list_empty(&mm->context.pgtable_list)) {
-			page = list_first_entry(&mm->context.pgtable_list,
-						struct page, lru);
-			mask = atomic_read(&page->_refcount) >> 24;
-			mask = (mask | (mask >> 4)) & 3;
-			if (mask != 3) {
-				table = (unsigned long *) page_to_virt(page);
-				bit = mask & 1;		/* =1 -> second 2K */
-				if (bit)
-					table += PTRS_PER_PTE;
-				atomic_xor_bits(&page->_refcount,
-							1U << (bit + 24));
-				list_del(&page->lru);
-			}
-		}
-		spin_unlock_bh(&mm->context.lock);
-		if (table)
-			return table;
-	}
-	/* Allocate a fresh page */
-	page = alloc_page(GFP_KERNEL);
-	if (!page)
+
+	if (mm == &init_mm)
+		gfp &= ~__GFP_ACCOUNT;
+	ptdesc = pagetable_alloc_noprof(gfp, 0);
+	if (!ptdesc)
 		return NULL;
-	if (!pgtable_pte_page_ctor(page)) {
-		__free_page(page);
+	if (!pagetable_pte_ctor(mm, ptdesc)) {
+		pagetable_free(ptdesc);
 		return NULL;
 	}
-	arch_set_page_dat(page, 0);
-	/* Initialize page table */
-	table = (unsigned long *) page_to_virt(page);
-	if (mm_alloc_pgste(mm)) {
-		/* Return 4K page table with PGSTEs */
-		atomic_xor_bits(&page->_refcount, 3 << 24);
-		memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
-		memset64((u64 *)table + PTRS_PER_PTE, 0, PTRS_PER_PTE);
-	} else {
-		/* Return the first 2K fragment of the page */
-		atomic_xor_bits(&page->_refcount, 1 << 24);
-		memset64((u64 *)table, _PAGE_INVALID, 2 * PTRS_PER_PTE);
-		spin_lock_bh(&mm->context.lock);
-		list_add(&page->lru, &mm->context.pgtable_list);
-		spin_unlock_bh(&mm->context.lock);
-	}
+	table = ptdesc_address(ptdesc);
+	__arch_set_page_dat(table, 1);
+	memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
+	memset64((u64 *)table + PTRS_PER_PTE, 0, PTRS_PER_PTE);
 	return table;
 }
 
 void page_table_free(struct mm_struct *mm, unsigned long *table)
 {
-	struct page *page;
-	unsigned int bit, mask;
-
-	page = virt_to_page(table);
-	if (!mm_alloc_pgste(mm)) {
-		/* Free 2K page table fragment of a 4K page */
-		bit = ((unsigned long) table & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t));
-		spin_lock_bh(&mm->context.lock);
-		mask = atomic_xor_bits(&page->_refcount, 1U << (bit + 24));
-		mask >>= 24;
-		if (mask & 3)
-			list_add(&page->lru, &mm->context.pgtable_list);
-		else
-			list_del(&page->lru);
-		spin_unlock_bh(&mm->context.lock);
-		if (mask != 0)
-			return;
-	} else {
-		atomic_xor_bits(&page->_refcount, 3U << 24);
-	}
+	struct ptdesc *ptdesc = virt_to_ptdesc(table);
 
-	pgtable_pte_page_dtor(page);
-	__free_page(page);
+	if (pagetable_is_reserved(ptdesc))
+		return free_reserved_ptdesc(ptdesc);
+	pagetable_dtor_free(ptdesc);
 }
 
-void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table,
-			 unsigned long vmaddr)
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static void pte_free_now(struct rcu_head *head)
 {
-	struct mm_struct *mm;
-	struct page *page;
-	unsigned int bit, mask;
-
-	mm = tlb->mm;
-	page = virt_to_page(table);
-	if (mm_alloc_pgste(mm)) {
-		gmap_unlink(mm, table, vmaddr);
-		table = (unsigned long *) ((unsigned long)table | 3);
-		tlb_remove_table(tlb, table);
-		return;
-	}
-	bit = ((unsigned long) table & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t));
-	spin_lock_bh(&mm->context.lock);
-	mask = atomic_xor_bits(&page->_refcount, 0x11U << (bit + 24));
-	mask >>= 24;
-	if (mask & 3)
-		list_add_tail(&page->lru, &mm->context.pgtable_list);
-	else
-		list_del(&page->lru);
-	spin_unlock_bh(&mm->context.lock);
-	table = (unsigned long *) ((unsigned long) table | (1U << bit));
-	tlb_remove_table(tlb, table);
+	struct ptdesc *ptdesc = container_of(head, struct ptdesc, pt_rcu_head);
+
+	pagetable_dtor_free(ptdesc);
 }
 
-void __tlb_remove_table(void *_table)
+void pte_free_defer(struct mm_struct *mm, pgtable_t pgtable)
 {
-	unsigned int mask = (unsigned long) _table & 3;
-	void *table = (void *)((unsigned long) _table ^ mask);
-	struct page *page = virt_to_page(table);
+	struct ptdesc *ptdesc = virt_to_ptdesc(pgtable);
 
-	switch (mask) {
-	case 0:		/* pmd, pud, or p4d */
-		free_pages((unsigned long) table, 2);
-		break;
-	case 1:		/* lower 2K of a 4K page table */
-	case 2:		/* higher 2K of a 4K page table */
-		mask = atomic_xor_bits(&page->_refcount, mask << (4 + 24));
-		mask >>= 24;
-		if (mask != 0)
-			break;
-		fallthrough;
-	case 3:		/* 4K page table with pgstes */
-		if (mask & 3)
-			atomic_xor_bits(&page->_refcount, 3 << 24);
-		pgtable_pte_page_dtor(page);
-		__free_page(page);
-		break;
-	}
+	call_rcu(&ptdesc->pt_rcu_head, pte_free_now);
 }
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
 /*
  * Base infrastructure required to generate basic asces, region, segment,
@@ -322,34 +192,39 @@ void __tlb_remove_table(void *_table)
 
 static struct kmem_cache *base_pgt_cache;
 
-static unsigned long base_pgt_alloc(void)
+static unsigned long *base_pgt_alloc(void)
 {
-	u64 *table;
+	unsigned long *table;
 
 	table = kmem_cache_alloc(base_pgt_cache, GFP_KERNEL);
 	if (table)
-		memset64(table, _PAGE_INVALID, PTRS_PER_PTE);
-	return (unsigned long) table;
+		memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
+	return table;
 }
 
-static void base_pgt_free(unsigned long table)
+static void base_pgt_free(unsigned long *table)
 {
-	kmem_cache_free(base_pgt_cache, (void *) table);
+	kmem_cache_free(base_pgt_cache, table);
 }
 
-static unsigned long base_crst_alloc(unsigned long val)
+static unsigned long *base_crst_alloc(unsigned long val)
 {
-	unsigned long table;
+	unsigned long *table;
+	struct ptdesc *ptdesc;
 
-	table =	 __get_free_pages(GFP_KERNEL, CRST_ALLOC_ORDER);
-	if (table)
-		crst_table_init((unsigned long *)table, val);
+	ptdesc = pagetable_alloc(GFP_KERNEL, CRST_ALLOC_ORDER);
+	if (!ptdesc)
+		return NULL;
+	table = ptdesc_address(ptdesc);
+	crst_table_init(table, val);
 	return table;
 }
 
-static void base_crst_free(unsigned long table)
+static void base_crst_free(unsigned long *table)
 {
-	free_pages(table, CRST_ALLOC_ORDER);
+	if (!table)
+		return;
+	pagetable_free(virt_to_ptdesc(table));
 }
 
 #define BASE_ADDR_END_FUNC(NAME, SIZE)					\
@@ -361,7 +236,7 @@ static inline unsigned long base_##NAME##_addr_end(unsigned long addr,	\
 	return (next - 1) < (end - 1) ? next : end;			\
 }
 
-BASE_ADDR_END_FUNC(page,    _PAGE_SIZE)
+BASE_ADDR_END_FUNC(page,    PAGE_SIZE)
 BASE_ADDR_END_FUNC(segment, _SEGMENT_SIZE)
 BASE_ADDR_END_FUNC(region3, _REGION3_SIZE)
 BASE_ADDR_END_FUNC(region2, _REGION2_SIZE)
@@ -372,20 +247,20 @@ static inline unsigned long base_lra(unsigned long address)
 	unsigned long real;
 
 	asm volatile(
-		"	lra	%0,0(%1)\n"
+		"	lra	%0,0(%1)"
 		: "=d" (real) : "a" (address) : "cc");
 	return real;
 }
 
-static int base_page_walk(unsigned long origin, unsigned long addr,
+static int base_page_walk(unsigned long *origin, unsigned long addr,
 			  unsigned long end, int alloc)
 {
 	unsigned long *pte, next;
 
 	if (!alloc)
 		return 0;
-	pte = (unsigned long *) origin;
-	pte += (addr & _PAGE_INDEX) >> _PAGE_SHIFT;
+	pte = origin;
+	pte += (addr & _PAGE_INDEX) >> PAGE_SHIFT;
 	do {
 		next = base_page_addr_end(addr, end);
 		*pte = base_lra(addr);
@@ -393,13 +268,13 @@ static int base_page_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_segment_walk(unsigned long origin, unsigned long addr,
+static int base_segment_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *ste, next, table;
+	unsigned long *ste, next, *table;
 	int rc;
 
-	ste = (unsigned long *) origin;
+	ste = origin;
 	ste += (addr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT;
 	do {
 		next = base_segment_addr_end(addr, end);
@@ -409,9 +284,9 @@ static int base_segment_walk(unsigned long origin, unsigned long addr,
 			table = base_pgt_alloc();
 			if (!table)
 				return -ENOMEM;
-			*ste = table | _SEGMENT_ENTRY;
+			*ste = __pa(table) | _SEGMENT_ENTRY;
 		}
-		table = *ste & _SEGMENT_ENTRY_ORIGIN;
+		table = __va(*ste & _SEGMENT_ENTRY_ORIGIN);
 		rc = base_page_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -422,13 +297,13 @@ static int base_segment_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region3_walk(unsigned long origin, unsigned long addr,
+static int base_region3_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rtte, next, table;
+	unsigned long *rtte, next, *table;
 	int rc;
 
-	rtte = (unsigned long *) origin;
+	rtte = origin;
 	rtte += (addr & _REGION3_INDEX) >> _REGION3_SHIFT;
 	do {
 		next = base_region3_addr_end(addr, end);
@@ -438,9 +313,9 @@ static int base_region3_walk(unsigned long origin, unsigned long addr,
 			table = base_crst_alloc(_SEGMENT_ENTRY_EMPTY);
 			if (!table)
 				return -ENOMEM;
-			*rtte = table | _REGION3_ENTRY;
+			*rtte = __pa(table) | _REGION3_ENTRY;
 		}
-		table = *rtte & _REGION_ENTRY_ORIGIN;
+		table = __va(*rtte & _REGION_ENTRY_ORIGIN);
 		rc = base_segment_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -450,13 +325,13 @@ static int base_region3_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region2_walk(unsigned long origin, unsigned long addr,
+static int base_region2_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rste, next, table;
+	unsigned long *rste, next, *table;
 	int rc;
 
-	rste = (unsigned long *) origin;
+	rste = origin;
 	rste += (addr & _REGION2_INDEX) >> _REGION2_SHIFT;
 	do {
 		next = base_region2_addr_end(addr, end);
@@ -466,9 +341,9 @@ static int base_region2_walk(unsigned long origin, unsigned long addr,
 			table = base_crst_alloc(_REGION3_ENTRY_EMPTY);
 			if (!table)
 				return -ENOMEM;
-			*rste = table | _REGION2_ENTRY;
+			*rste = __pa(table) | _REGION2_ENTRY;
 		}
-		table = *rste & _REGION_ENTRY_ORIGIN;
+		table = __va(*rste & _REGION_ENTRY_ORIGIN);
 		rc = base_region3_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -478,13 +353,13 @@ static int base_region2_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region1_walk(unsigned long origin, unsigned long addr,
+static int base_region1_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rfte, next, table;
+	unsigned long *rfte, next, *table;
 	int rc;
 
-	rfte = (unsigned long *) origin;
+	rfte = origin;
 	rfte += (addr & _REGION1_INDEX) >> _REGION1_SHIFT;
 	do {
 		next = base_region1_addr_end(addr, end);
@@ -494,9 +369,9 @@ static int base_region1_walk(unsigned long origin, unsigned long addr,
 			table = base_crst_alloc(_REGION2_ENTRY_EMPTY);
 			if (!table)
 				return -ENOMEM;
-			*rfte = table | _REGION1_ENTRY;
+			*rfte = __pa(table) | _REGION1_ENTRY;
 		}
-		table = *rfte & _REGION_ENTRY_ORIGIN;
+		table = __va(*rfte & _REGION_ENTRY_ORIGIN);
 		rc = base_region2_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -515,7 +390,7 @@ static int base_region1_walk(unsigned long origin, unsigned long addr,
  */
 void base_asce_free(unsigned long asce)
 {
-	unsigned long table = asce & _ASCE_ORIGIN;
+	unsigned long *table = __va(asce & _ASCE_ORIGIN);
 
 	if (!asce)
 		return;
@@ -567,7 +442,7 @@ static int base_pgt_cache_init(void)
  */
 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages)
 {
-	unsigned long asce, table, end;
+	unsigned long asce, *table, end;
 	int rc;
 
 	if (base_pgt_cache_init())
@@ -578,25 +453,25 @@ unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages)
 		if (!table)
 			return 0;
 		rc = base_segment_walk(table, addr, end, 1);
-		asce = table | _ASCE_TYPE_SEGMENT | _ASCE_TABLE_LENGTH;
+		asce = __pa(table) | _ASCE_TYPE_SEGMENT | _ASCE_TABLE_LENGTH;
 	} else if (end <= _REGION2_SIZE) {
 		table = base_crst_alloc(_REGION3_ENTRY_EMPTY);
 		if (!table)
 			return 0;
 		rc = base_region3_walk(table, addr, end, 1);
-		asce = table | _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
+		asce = __pa(table) | _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
 	} else if (end <= _REGION1_SIZE) {
 		table = base_crst_alloc(_REGION2_ENTRY_EMPTY);
 		if (!table)
 			return 0;
 		rc = base_region2_walk(table, addr, end, 1);
-		asce = table | _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH;
+		asce = __pa(table) | _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH;
 	} else {
 		table = base_crst_alloc(_REGION1_ENTRY_EMPTY);
 		if (!table)
 			return 0;
 		rc = base_region1_walk(table, addr, end, 1);
-		asce = table | _ASCE_TYPE_REGION1 | _ASCE_TABLE_LENGTH;
+		asce = __pa(table) | _ASCE_TYPE_REGION1 | _ASCE_TABLE_LENGTH;
 	}
 	if (rc) {
 		base_asce_free(asce);