Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull VFS changes from Al Viro:
 "First pile out of several (there _definitely_ will be more).  Stuff in
  this one:

   - unification of d_splice_alias()/d_materialize_unique()

   - iov_iter rewrite

   - killing a bunch of ->f_path.dentry users (and f_dentry macro).

     Getting that completed will make life much simpler for
     unionmount/overlayfs, since then we'll be able to limit the places
     sensitive to file _dentry_ to reasonably few.  Which allows to have
     file_inode(file) pointing to inode in a covered layer, with dentry
     pointing to (negative) dentry in union one.

     Still not complete, but much closer now.

   - crapectomy in lustre (dead code removal, mostly)

   - "let's make seq_printf return nothing" preparations

   - assorted cleanups and fixes

  There _definitely_ will be more piles"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  copy_from_iter_nocache()
  new helper: iov_iter_kvec()
  csum_and_copy_..._iter()
  iov_iter.c: handle ITER_KVEC directly
  iov_iter.c: convert copy_to_iter() to iterate_and_advance
  iov_iter.c: convert copy_from_iter() to iterate_and_advance
  iov_iter.c: get rid of bvec_copy_page_{to,from}_iter()
  iov_iter.c: convert iov_iter_zero() to iterate_and_advance
  iov_iter.c: convert iov_iter_get_pages_alloc() to iterate_all_kinds
  iov_iter.c: convert iov_iter_get_pages() to iterate_all_kinds
  iov_iter.c: convert iov_iter_npages() to iterate_all_kinds
  iov_iter.c: iterate_and_advance
  iov_iter.c: macros for iterating over iov_iter
  kill f_dentry macro
  dcache: fix kmemcheck warning in switch_names
  new helper: audit_file()
  nfsd_vfs_write(): use file_inode()
  ncpfs: use file_inode()
  kill f_dentry uses
  lockd: get rid of ->f_path.dentry->d_sb
  ...

include/linux/audit.h

@@ -130,6 +130,7 @@ extern void audit_putname(struct filename *name);
 #define AUDIT_INODE_HIDDEN	2	/* audit record should be hidden */
 extern void __audit_inode(struct filename *name, const struct dentry *dentry,
 				unsigned int flags);
+extern void __audit_file(const struct file *);
 extern void __audit_inode_child(const struct inode *parent,
 				const struct dentry *dentry,
 				const unsigned char type);
@@ -183,6 +184,11 @@ static inline void audit_inode(struct filename *name,
 		__audit_inode(name, dentry, flags);
 	}
 }
+static inline void audit_file(struct file *file)
+{
+	if (unlikely(!audit_dummy_context()))
+		__audit_file(file);
+}
 static inline void audit_inode_parent_hidden(struct filename *name,
 						const struct dentry *dentry)
 {
@@ -357,6 +363,9 @@ static inline void audit_inode(struct filename *name,
 				const struct dentry *dentry,
 				unsigned int parent)
 { }
+static inline void audit_file(struct file *file)
+{
+}
 static inline void audit_inode_parent_hidden(struct filename *name,
 				const struct dentry *dentry)
 { }

include/linux/cgroup.h

@@ -367,8 +367,8 @@ struct css_set {
  * struct cftype: handler definitions for cgroup control files
  *
  * When reading/writing to a file:
- *	- the cgroup to use is file->f_dentry->d_parent->d_fsdata
- *	- the 'cftype' of the file is file->f_dentry->d_fsdata
+ *	- the cgroup to use is file->f_path.dentry->d_parent->d_fsdata
+ *	- the 'cftype' of the file is file->f_path.dentry->d_fsdata
  */
 
 /* cftype->flags */

include/linux/dcache.h

@@ -124,15 +124,15 @@ struct dentry {
 	void *d_fsdata;			/* fs-specific data */
 
 	struct list_head d_lru;		/* LRU list */
+	struct list_head d_child;	/* child of parent list */
+	struct list_head d_subdirs;	/* our children */
 	/*
-	 * d_child and d_rcu can share memory
+	 * d_alias and d_rcu can share memory
 	 */
 	union {
-		struct list_head d_child;	/* child of parent list */
+		struct hlist_node d_alias;	/* inode alias list */
 	 	struct rcu_head d_rcu;
 	} d_u;
-	struct list_head d_subdirs;	/* our children */
-	struct hlist_node d_alias;	/* inode alias list */
 };
 
 /*
@@ -230,7 +230,6 @@ extern seqlock_t rename_lock;
  */
 extern void d_instantiate(struct dentry *, struct inode *);
 extern struct dentry * d_instantiate_unique(struct dentry *, struct inode *);
-extern struct dentry * d_materialise_unique(struct dentry *, struct inode *);
 extern int d_instantiate_no_diralias(struct dentry *, struct inode *);
 extern void __d_drop(struct dentry *dentry);
 extern void d_drop(struct dentry *dentry);

include/linux/debugfs.h

@@ -92,8 +92,8 @@ struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
 				     struct dentry *parent,
 				     struct debugfs_regset32 *regset);
 
-int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
-			 int nregs, void __iomem *base, char *prefix);
+void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+			  int nregs, void __iomem *base, char *prefix);
 
 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
 					struct dentry *parent,
@@ -233,10 +233,9 @@ static inline struct dentry *debugfs_create_regset32(const char *name,
 	return ERR_PTR(-ENODEV);
 }
 
-static inline int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
 			 int nregs, void __iomem *base, char *prefix)
 {
-	return 0;
 }
 
 static inline bool debugfs_initialized(void)

include/linux/fs.h

@@ -786,7 +786,6 @@ struct file {
 		struct rcu_head 	fu_rcuhead;
 	} f_u;
 	struct path		f_path;
-#define f_dentry	f_path.dentry
 	struct inode		*f_inode;	/* cached value */
 	const struct file_operations	*f_op;
 
@@ -1465,7 +1464,10 @@ int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags);
  * This allows the kernel to read directories into kernel space or
  * to have different dirent layouts depending on the binary type.
  */
-typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
+struct dir_context;
+typedef int (*filldir_t)(struct dir_context *, const char *, int, loff_t, u64,
+			 unsigned);
+
 struct dir_context {
 	const filldir_t actor;
 	loff_t pos;
@@ -1511,7 +1513,7 @@ struct file_operations {
 	int (*setlease)(struct file *, long, struct file_lock **, void **);
 	long (*fallocate)(struct file *file, int mode, loff_t offset,
 			  loff_t len);
-	int (*show_fdinfo)(struct seq_file *m, struct file *f);
+	void (*show_fdinfo)(struct seq_file *m, struct file *f);
 };
 
 struct inode_operations {
@@ -2787,6 +2789,11 @@ static inline void inode_has_no_xattr(struct inode *inode)
 		inode->i_flags |= S_NOSEC;
 }
 
+static inline bool is_root_inode(struct inode *inode)
+{
+	return inode == inode->i_sb->s_root->d_inode;
+}
+
 static inline bool dir_emit(struct dir_context *ctx,
 			    const char *name, int namelen,
 			    u64 ino, unsigned type)

include/linux/seq_file.h

@@ -42,6 +42,21 @@ struct seq_operations {
 
 #define SEQ_SKIP 1
 
+/**
+ * seq_has_overflowed - check if the buffer has overflowed
+ * @m: the seq_file handle
+ *
+ * seq_files have a buffer which may overflow. When this happens a larger
+ * buffer is reallocated and all the data will be printed again.
+ * The overflow state is true when m->count == m->size.
+ *
+ * Returns true if the buffer received more than it can hold.
+ */
+static inline bool seq_has_overflowed(struct seq_file *m)
+{
+	return m->count == m->size;
+}
+
 /**
  * seq_get_buf - get buffer to write arbitrary data to
  * @m: the seq_file handle

include/linux/uio.h

@@ -31,6 +31,7 @@ struct iov_iter {
 	size_t count;
 	union {
 		const struct iovec *iov;
+		const struct kvec *kvec;
 		const struct bio_vec *bvec;
 	};
 	unsigned long nr_segs;
@@ -82,10 +83,13 @@ size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
 			 struct iov_iter *i);
 size_t copy_to_iter(void *addr, size_t bytes, struct iov_iter *i);
 size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i);
+size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i);
 size_t iov_iter_zero(size_t bytes, struct iov_iter *);
 unsigned long iov_iter_alignment(const struct iov_iter *i);
 void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov,
 			unsigned long nr_segs, size_t count);
+void iov_iter_kvec(struct iov_iter *i, int direction, const struct kvec *iov,
+			unsigned long nr_segs, size_t count);
 ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
 			size_t maxsize, unsigned maxpages, size_t *start);
 ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
@@ -123,6 +127,8 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
 {
 	i->count = count;
 }
+size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
+size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 
 int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
 int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len);