Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "The rest of MM and the rest of everything else: hotfixes, ipc, misc,
  procfs, lib, cleanups, arm"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits)
  ARM: dma-api: fix max_pfn off-by-one error in __dma_supported()
  treewide: remove redundant IS_ERR() before error code check
  include/linux/cpumask.h: don't calculate length of the input string
  lib: new testcases for bitmap_parse{_user}
  lib: rework bitmap_parse()
  lib: make bitmap_parse_user a wrapper on bitmap_parse
  lib: add test for bitmap_parse()
  bitops: more BITS_TO_* macros
  lib/string: add strnchrnul()
  proc: convert everything to "struct proc_ops"
  proc: decouple proc from VFS with "struct proc_ops"
  asm-generic/tlb: provide MMU_GATHER_TABLE_FREE
  asm-generic/tlb: rename HAVE_MMU_GATHER_NO_GATHER
  asm-generic/tlb: rename HAVE_MMU_GATHER_PAGE_SIZE
  asm-generic/tlb: rename HAVE_RCU_TABLE_FREE
  asm-generic/tlb: add missing CONFIG symbol
  asm-gemeric/tlb: remove stray function declarations
  asm-generic/tlb: avoid potential double flush
  mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush
  powerpc/mmu_gather: enable RCU_TABLE_FREE even for !SMP case
  ...

13 files changed, 115 insertions, 34 deletions

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 80ad521116d7..e52ceb1a73d3 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -186,7 +186,7 @@ bitmap_find_next_zero_area(unsigned long *map,
 					      align_mask, 0);
 }
 
-extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
+extern int bitmap_parse(const char *buf, unsigned int buflen,
 			unsigned long *dst, int nbits);
 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
 			unsigned long *dst, int nbits);
@@ -454,12 +454,6 @@ static inline void bitmap_replace(unsigned long *dst,
 		__bitmap_replace(dst, old, new, mask, nbits);
 }
 
-static inline int bitmap_parse(const char *buf, unsigned int buflen,
-			unsigned long *maskp, int nmaskbits)
-{
-	return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
-}
-
 static inline void bitmap_next_clear_region(unsigned long *bitmap,
 					    unsigned int *rs, unsigned int *re,
 					    unsigned int end)
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 6c7c4133c25c..47f54b459c26 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -11,8 +11,10 @@
 #  define aligned_byte_mask(n) (~0xffUL << (BITS_PER_LONG - 8 - 8*(n)))
 #endif
 
-#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
+#define BITS_PER_TYPE(type)	(sizeof(type) * BITS_PER_BYTE)
 #define BITS_TO_LONGS(nr)	DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
+#define BITS_TO_U64(nr)		DIV_ROUND_UP(nr, BITS_PER_TYPE(u64))
+#define BITS_TO_U32(nr)		DIV_ROUND_UP(nr, BITS_PER_TYPE(u32))
 #define BITS_TO_BYTES(nr)	DIV_ROUND_UP(nr, BITS_PER_TYPE(char))
 
 extern unsigned int __sw_hweight8(unsigned int w);
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 78a73eba64dd..d5cc88514aee 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -663,9 +663,7 @@ static inline int cpumask_parselist_user(const char __user *buf, int len,
  */
 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
 {
-	unsigned int len = strchrnul(buf, '\n') - buf;
-
-	return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
+	return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
 }
 
 /**
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index ffa6ad12d84a..f4d59155f3d4 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -96,8 +96,8 @@ extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
 /* VM interface that may be used by firmware interface */
 extern int online_pages(unsigned long pfn, unsigned long nr_pages,
 			int online_type, int nid);
-extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
-	unsigned long *valid_start, unsigned long *valid_end);
+extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
+					 unsigned long end_pfn);
 extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
 						unsigned long end_pfn);
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index faa3bb5fe633..52269e56c514 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2182,12 +2182,6 @@ extern int __meminit __early_pfn_to_nid(unsigned long pfn,
 					struct mminit_pfnnid_cache *state);
 #endif
 
-#if !defined(CONFIG_FLAT_NODE_MEM_MAP)
-void zero_resv_unavail(void);
-#else
-static inline void zero_resv_unavail(void) {}
-#endif
-
 extern void set_dma_reserve(unsigned long new_dma_reserve);
 extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long,
 		enum memmap_context, struct vmem_altmap *);
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c2bc309d1634..462f6873905a 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1379,6 +1379,16 @@ static inline int pfn_present(unsigned long pfn)
 	return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
 }
 
+static inline unsigned long next_present_section_nr(unsigned long section_nr)
+{
+	while (++section_nr <= __highest_present_section_nr) {
+		if (present_section_nr(section_nr))
+			return section_nr;
+	}
+
+	return -1;
+}
+
 /*
  * These are _only_ used during initialisation, therefore they
  * can use __initdata ...  They could have names to indicate
diff --git a/include/linux/pagewalk.h b/include/linux/pagewalk.h
index 6ec82e92c87f..b1cb6b753abb 100644
--- a/include/linux/pagewalk.h
+++ b/include/linux/pagewalk.h
@@ -8,16 +8,19 @@ struct mm_walk;
 
 /**
  * mm_walk_ops - callbacks for walk_page_range
- * @pud_entry:		if set, called for each non-empty PUD (2nd-level) entry
- *			this handler should only handle pud_trans_huge() puds.
- *			the pmd_entry or pte_entry callbacks will be used for
- *			regular PUDs.
- * @pmd_entry:		if set, called for each non-empty PMD (3rd-level) entry
+ * @pgd_entry:		if set, called for each non-empty PGD (top-level) entry
+ * @p4d_entry:		if set, called for each non-empty P4D entry
+ * @pud_entry:		if set, called for each non-empty PUD entry
+ * @pmd_entry:		if set, called for each non-empty PMD entry
  *			this handler is required to be able to handle
  *			pmd_trans_huge() pmds.  They may simply choose to
  *			split_huge_page() instead of handling it explicitly.
- * @pte_entry:		if set, called for each non-empty PTE (4th-level) entry
- * @pte_hole:		if set, called for each hole at all levels
+ * @pte_entry:		if set, called for each non-empty PTE (lowest-level)
+ *			entry
+ * @pte_hole:		if set, called for each hole at all levels,
+ *			depth is -1 if not known, 0:PGD, 1:P4D, 2:PUD, 3:PMD
+ *			4:PTE. Any folded depths (where PTRS_PER_P?D is equal
+ *			to 1) are skipped.
  * @hugetlb_entry:	if set, called for each hugetlb entry
  * @test_walk:		caller specific callback function to determine whether
  *			we walk over the current vma or not. Returning 0 means
@@ -27,8 +30,15 @@ struct mm_walk;
  * @pre_vma:            if set, called before starting walk on a non-null vma.
  * @post_vma:           if set, called after a walk on a non-null vma, provided
  *                      that @pre_vma and the vma walk succeeded.
+ *
+ * p?d_entry callbacks are called even if those levels are folded on a
+ * particular architecture/configuration.
  */
 struct mm_walk_ops {
+	int (*pgd_entry)(pgd_t *pgd, unsigned long addr,
+			 unsigned long next, struct mm_walk *walk);
+	int (*p4d_entry)(p4d_t *p4d, unsigned long addr,
+			 unsigned long next, struct mm_walk *walk);
 	int (*pud_entry)(pud_t *pud, unsigned long addr,
 			 unsigned long next, struct mm_walk *walk);
 	int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
@@ -36,7 +46,7 @@ struct mm_walk_ops {
 	int (*pte_entry)(pte_t *pte, unsigned long addr,
 			 unsigned long next, struct mm_walk *walk);
 	int (*pte_hole)(unsigned long addr, unsigned long next,
-			struct mm_walk *walk);
+			int depth, struct mm_walk *walk);
 	int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
 			     unsigned long addr, unsigned long next,
 			     struct mm_walk *walk);
@@ -47,11 +57,27 @@ struct mm_walk_ops {
 	void (*post_vma)(struct mm_walk *walk);
 };
 
+/*
+ * Action for pud_entry / pmd_entry callbacks.
+ * ACTION_SUBTREE is the default
+ */
+enum page_walk_action {
+	/* Descend to next level, splitting huge pages if needed and possible */
+	ACTION_SUBTREE = 0,
+	/* Continue to next entry at this level (ignoring any subtree) */
+	ACTION_CONTINUE = 1,
+	/* Call again for this entry */
+	ACTION_AGAIN = 2
+};
+
 /**
  * mm_walk - walk_page_range data
  * @ops:	operation to call during the walk
  * @mm:		mm_struct representing the target process of page table walk
+ * @pgd:	pointer to PGD; only valid with no_vma (otherwise set to NULL)
  * @vma:	vma currently walked (NULL if walking outside vmas)
+ * @action:	next action to perform (see enum page_walk_action)
+ * @no_vma:	walk ignoring vmas (vma will always be NULL)
  * @private:	private data for callbacks' usage
  *
  * (see the comment on walk_page_range() for more details)
@@ -59,13 +85,20 @@ struct mm_walk_ops {
 struct mm_walk {
 	const struct mm_walk_ops *ops;
 	struct mm_struct *mm;
+	pgd_t *pgd;
 	struct vm_area_struct *vma;
+	enum page_walk_action action;
+	bool no_vma;
 	void *private;
 };
 
 int walk_page_range(struct mm_struct *mm, unsigned long start,
 		unsigned long end, const struct mm_walk_ops *ops,
 		void *private);
+int walk_page_range_novma(struct mm_struct *mm, unsigned long start,
+			  unsigned long end, const struct mm_walk_ops *ops,
+			  pgd_t *pgd,
+			  void *private);
 int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops,
 		void *private);
 int walk_page_mapping(struct address_space *mapping, pgoff_t first_index,
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 0640be56dcbd..3dfa92633af3 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -12,6 +12,21 @@ struct proc_dir_entry;
 struct seq_file;
 struct seq_operations;
 
+struct proc_ops {
+	int	(*proc_open)(struct inode *, struct file *);
+	ssize_t	(*proc_read)(struct file *, char __user *, size_t, loff_t *);
+	ssize_t	(*proc_write)(struct file *, const char __user *, size_t, loff_t *);
+	loff_t	(*proc_lseek)(struct file *, loff_t, int);
+	int	(*proc_release)(struct inode *, struct file *);
+	__poll_t (*proc_poll)(struct file *, struct poll_table_struct *);
+	long	(*proc_ioctl)(struct file *, unsigned int, unsigned long);
+#ifdef CONFIG_COMPAT
+	long	(*proc_compat_ioctl)(struct file *, unsigned int, unsigned long);
+#endif
+	int	(*proc_mmap)(struct file *, struct vm_area_struct *);
+	unsigned long (*proc_get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
+};
+
 #ifdef CONFIG_PROC_FS
 
 typedef int (*proc_write_t)(struct file *, char *, size_t);
@@ -43,10 +58,10 @@ struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
  
 extern struct proc_dir_entry *proc_create_data(const char *, umode_t,
 					       struct proc_dir_entry *,
-					       const struct file_operations *,
+					       const struct proc_ops *,
 					       void *);
 
-struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct file_operations *proc_fops);
+struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct proc_ops *proc_ops);
 extern void proc_set_size(struct proc_dir_entry *, loff_t);
 extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t);
 extern void *PDE_DATA(const struct inode *);
@@ -108,8 +123,8 @@ static inline struct proc_dir_entry *proc_mkdir_mode(const char *name,
 #define proc_create_seq(name, mode, parent, ops) ({NULL;})
 #define proc_create_single(name, mode, parent, show) ({NULL;})
 #define proc_create_single_data(name, mode, parent, show, data) ({NULL;})
-#define proc_create(name, mode, parent, proc_fops) ({NULL;})
-#define proc_create_data(name, mode, parent, proc_fops, data) ({NULL;})
+#define proc_create(name, mode, parent, proc_ops) ({NULL;})
+#define proc_create_data(name, mode, parent, proc_ops, data) ({NULL;})
 
 static inline void proc_set_size(struct proc_dir_entry *de, loff_t size) {}
 static inline void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) {}
diff --git a/include/linux/ptdump.h b/include/linux/ptdump.h
new file mode 100644
index 000000000000..a67065c403c3
--- /dev/null
+++ b/include/linux/ptdump.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _LINUX_PTDUMP_H
+#define _LINUX_PTDUMP_H
+
+#include <linux/mm_types.h>
+
+struct ptdump_range {
+	unsigned long start;
+	unsigned long end;
+};
+
+struct ptdump_state {
+	/* level is 0:PGD to 4:PTE, or -1 if unknown */
+	void (*note_page)(struct ptdump_state *st, unsigned long addr,
+			  int level, unsigned long val);
+	const struct ptdump_range *range;
+};
+
+void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd);
+
+#endif /* _LINUX_PTDUMP_H */
diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 5998e1f4ff06..770c2bf3aa43 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -160,6 +160,19 @@ static const struct file_operations __name ## _fops = {			\
 	.release	= single_release,				\
 }
 
+#define DEFINE_PROC_SHOW_ATTRIBUTE(__name)				\
+static int __name ## _open(struct inode *inode, struct file *file)	\
+{									\
+	return single_open(file, __name ## _show, inode->i_private);	\
+}									\
+									\
+static const struct proc_ops __name ## _proc_ops = {			\
+	.proc_open	= __name ## _open,				\
+	.proc_read	= seq_read,					\
+	.proc_lseek	= seq_lseek,					\
+	.proc_release	= single_release,				\
+}
+
 static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
 {
 #ifdef CONFIG_USER_NS
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 877a95c6a2d2..03a389358562 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -184,7 +184,6 @@ void memcg_deactivate_kmem_caches(struct mem_cgroup *, struct mem_cgroup *);
 /*
  * Common kmalloc functions provided by all allocators
  */
-void * __must_check __krealloc(const void *, size_t, gfp_t);
 void * __must_check krealloc(const void *, size_t, gfp_t);
 void kfree(const void *);
 void kzfree(const void *);
diff --git a/include/linux/string.h b/include/linux/string.h
index 02894e417565..6dfbb2efa815 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -62,6 +62,7 @@ extern char * strchr(const char *,int);
 #ifndef __HAVE_ARCH_STRCHRNUL
 extern char * strchrnul(const char *,int);
 #endif
+extern char * strnchrnul(const char *, size_t, int);
 #ifndef __HAVE_ARCH_STRNCHR
 extern char * strnchr(const char *, size_t, int);
 #endif
diff --git a/include/linux/sunrpc/stats.h b/include/linux/sunrpc/stats.h
index 84b92b4ad1c0..d94d4f410507 100644
--- a/include/linux/sunrpc/stats.h
+++ b/include/linux/sunrpc/stats.h
@@ -63,7 +63,7 @@ struct proc_dir_entry *	rpc_proc_register(struct net *,struct rpc_stat *);
 void			rpc_proc_unregister(struct net *,const char *);
 void			rpc_proc_zero(const struct rpc_program *);
 struct proc_dir_entry *	svc_proc_register(struct net *, struct svc_stat *,
-					  const struct file_operations *);
+					  const struct proc_ops *);
 void			svc_proc_unregister(struct net *, const char *);
 
 void			svc_seq_show(struct seq_file *,
@@ -75,7 +75,7 @@ static inline void rpc_proc_unregister(struct net *net, const char *p) {}
 static inline void rpc_proc_zero(const struct rpc_program *p) {}
 
 static inline struct proc_dir_entry *svc_proc_register(struct net *net, struct svc_stat *s,
-						       const struct file_operations *f) { return NULL; }
+						       const struct proc_ops *proc_ops) { return NULL; }
 static inline void svc_proc_unregister(struct net *net, const char *p) {}
 
 static inline void svc_seq_show(struct seq_file *seq,