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

Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...

3 files changed, 65 insertions, 83 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 6aaa8112c538..2c90d07c0b3a 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -725,8 +725,7 @@ out_nls:
 	goto out;
 }
 
-static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
-				   unsigned long nr_segs, loff_t pos)
+static ssize_t cifs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
@@ -737,14 +736,14 @@ static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	if (written)
 		return written;
 
-	written = generic_file_aio_write(iocb, iov, nr_segs, pos);
+	written = generic_file_write_iter(iocb, from);
 
 	if (CIFS_CACHE_WRITE(CIFS_I(inode)))
 		goto out;
 
 	rc = filemap_fdatawrite(inode->i_mapping);
 	if (rc)
-		cifs_dbg(FYI, "cifs_file_aio_write: %d rc on %p inode\n",
+		cifs_dbg(FYI, "cifs_file_write_iter: %d rc on %p inode\n",
 			 rc, inode);
 
 out:
@@ -880,10 +879,10 @@ const struct inode_operations cifs_symlink_inode_ops = {
 };
 
 const struct file_operations cifs_file_ops = {
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = generic_file_aio_read,
-	.aio_write = cifs_file_aio_write,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = generic_file_read_iter,
+	.write_iter = cifs_file_write_iter,
 	.open = cifs_open,
 	.release = cifs_close,
 	.lock = cifs_lock,
@@ -899,10 +898,10 @@ const struct file_operations cifs_file_ops = {
 };
 
 const struct file_operations cifs_file_strict_ops = {
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = cifs_strict_readv,
-	.aio_write = cifs_strict_writev,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = cifs_strict_readv,
+	.write_iter = cifs_strict_writev,
 	.open = cifs_open,
 	.release = cifs_close,
 	.lock = cifs_lock,
@@ -919,10 +918,10 @@ const struct file_operations cifs_file_strict_ops = {
 
 const struct file_operations cifs_file_direct_ops = {
 	/* BB reevaluate whether they can be done with directio, no cache */
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = cifs_user_readv,
-	.aio_write = cifs_user_writev,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = cifs_user_readv,
+	.write_iter = cifs_user_writev,
 	.open = cifs_open,
 	.release = cifs_close,
 	.lock = cifs_lock,
@@ -938,10 +937,10 @@ const struct file_operations cifs_file_direct_ops = {
 };
 
 const struct file_operations cifs_file_nobrl_ops = {
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = generic_file_aio_read,
-	.aio_write = cifs_file_aio_write,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = generic_file_read_iter,
+	.write_iter = cifs_file_write_iter,
 	.open = cifs_open,
 	.release = cifs_close,
 	.fsync = cifs_fsync,
@@ -956,10 +955,10 @@ const struct file_operations cifs_file_nobrl_ops = {
 };
 
 const struct file_operations cifs_file_strict_nobrl_ops = {
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = cifs_strict_readv,
-	.aio_write = cifs_strict_writev,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = cifs_strict_readv,
+	.write_iter = cifs_strict_writev,
 	.open = cifs_open,
 	.release = cifs_close,
 	.fsync = cifs_strict_fsync,
@@ -975,10 +974,10 @@ const struct file_operations cifs_file_strict_nobrl_ops = {
 
 const struct file_operations cifs_file_direct_nobrl_ops = {
 	/* BB reevaluate whether they can be done with directio, no cache */
-	.read = do_sync_read,
-	.write = do_sync_write,
-	.aio_read = cifs_user_readv,
-	.aio_write = cifs_user_writev,
+	.read = new_sync_read,
+	.write = new_sync_write,
+	.read_iter = cifs_user_readv,
+	.write_iter = cifs_user_writev,
 	.open = cifs_open,
 	.release = cifs_close,
 	.fsync = cifs_fsync,
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 8fe51166d6e3..70f178a7c759 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -95,14 +95,10 @@ extern const struct file_operations cifs_file_strict_nobrl_ops;
 extern int cifs_open(struct inode *inode, struct file *file);
 extern int cifs_close(struct inode *inode, struct file *file);
 extern int cifs_closedir(struct inode *inode, struct file *file);
-extern ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
-			       unsigned long nr_segs, loff_t pos);
-extern ssize_t cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
-				 unsigned long nr_segs, loff_t pos);
-extern ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
-				unsigned long nr_segs, loff_t pos);
-extern ssize_t cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
-				  unsigned long nr_segs, loff_t pos);
+extern ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to);
+extern ssize_t cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to);
+extern ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from);
+extern ssize_t cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from);
 extern int cifs_lock(struct file *, int, struct file_lock *);
 extern int cifs_fsync(struct file *, loff_t, loff_t, int);
 extern int cifs_strict_fsync(struct file *, loff_t, loff_t, int);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 208f56eca4bf..e90a1e9aa627 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2385,14 +2385,12 @@ cifs_uncached_retry_writev(struct cifs_writedata *wdata)
 }
 
 static ssize_t
-cifs_iovec_write(struct file *file, const struct iovec *iov,
-		 unsigned long nr_segs, loff_t *poffset)
+cifs_iovec_write(struct file *file, struct iov_iter *from, loff_t *poffset)
 {
 	unsigned long nr_pages, i;
 	size_t bytes, copied, len, cur_len;
 	ssize_t total_written = 0;
 	loff_t offset;
-	struct iov_iter it;
 	struct cifsFileInfo *open_file;
 	struct cifs_tcon *tcon;
 	struct cifs_sb_info *cifs_sb;
@@ -2401,14 +2399,16 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
 	int rc;
 	pid_t pid;
 
-	len = iov_length(iov, nr_segs);
-	if (!len)
-		return 0;
-
+	len = iov_iter_count(from);
 	rc = generic_write_checks(file, poffset, &len, 0);
 	if (rc)
 		return rc;
 
+	if (!len)
+		return 0;
+
+	iov_iter_truncate(from, len);
+
 	INIT_LIST_HEAD(&wdata_list);
 	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 	open_file = file->private_data;
@@ -2424,7 +2424,6 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
 	else
 		pid = current->tgid;
 
-	iov_iter_init(&it, iov, nr_segs, len, 0);
 	do {
 		size_t save_len;
 
@@ -2444,11 +2443,10 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
 
 		save_len = cur_len;
 		for (i = 0; i < nr_pages; i++) {
-			bytes = min_t(const size_t, cur_len, PAGE_SIZE);
-			copied = iov_iter_copy_from_user(wdata->pages[i], &it,
-							 0, bytes);
+			bytes = min_t(size_t, cur_len, PAGE_SIZE);
+			copied = copy_page_from_iter(wdata->pages[i], 0, bytes,
+						     from);
 			cur_len -= copied;
-			iov_iter_advance(&it, copied);
 			/*
 			 * If we didn't copy as much as we expected, then that
 			 * may mean we trod into an unmapped area. Stop copying
@@ -2546,11 +2544,11 @@ restart_loop:
 	return total_written ? total_written : (ssize_t)rc;
 }
 
-ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
-				unsigned long nr_segs, loff_t pos)
+ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
 {
 	ssize_t written;
 	struct inode *inode;
+	loff_t pos = iocb->ki_pos;
 
 	inode = file_inode(iocb->ki_filp);
 
@@ -2560,7 +2558,7 @@ ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
 	 * write request.
 	 */
 
-	written = cifs_iovec_write(iocb->ki_filp, iov, nr_segs, &pos);
+	written = cifs_iovec_write(iocb->ki_filp, from, &pos);
 	if (written > 0) {
 		set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(inode)->flags);
 		iocb->ki_pos = pos;
@@ -2570,8 +2568,7 @@ ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
 }
 
 static ssize_t
-cifs_writev(struct kiocb *iocb, const struct iovec *iov,
-	    unsigned long nr_segs, loff_t pos)
+cifs_writev(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct file *file = iocb->ki_filp;
 	struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
@@ -2589,10 +2586,10 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov,
 	mutex_lock(&inode->i_mutex);
 	if (file->f_flags & O_APPEND)
 		lock_pos = i_size_read(inode);
-	if (!cifs_find_lock_conflict(cfile, lock_pos, iov_length(iov, nr_segs),
+	if (!cifs_find_lock_conflict(cfile, lock_pos, iov_iter_count(from),
 				     server->vals->exclusive_lock_type, NULL,
 				     CIFS_WRITE_OP)) {
-		rc = __generic_file_aio_write(iocb, iov, nr_segs);
+		rc = __generic_file_write_iter(iocb, from);
 		mutex_unlock(&inode->i_mutex);
 
 		if (rc > 0) {
@@ -2610,8 +2607,7 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov,
 }
 
 ssize_t
-cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
-		   unsigned long nr_segs, loff_t pos)
+cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
@@ -2629,11 +2625,10 @@ cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
 		if (cap_unix(tcon->ses) &&
 		(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
 		  && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
-			written = generic_file_aio_write(
-					iocb, iov, nr_segs, pos);
+			written = generic_file_write_iter(iocb, from);
 			goto out;
 		}
-		written = cifs_writev(iocb, iov, nr_segs, pos);
+		written = cifs_writev(iocb, from);
 		goto out;
 	}
 	/*
@@ -2642,7 +2637,7 @@ cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
 	 * affected pages because it may cause a error with mandatory locks on
 	 * these pages but not on the region from pos to ppos+len-1.
 	 */
-	written = cifs_user_writev(iocb, iov, nr_segs, pos);
+	written = cifs_user_writev(iocb, from);
 	if (written > 0 && CIFS_CACHE_READ(cinode)) {
 		/*
 		 * Windows 7 server can delay breaking level2 oplock if a write
@@ -2831,32 +2826,25 @@ cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
 	return total_read > 0 ? total_read : result;
 }
 
-ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
-			       unsigned long nr_segs, loff_t pos)
+ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
 {
 	struct file *file = iocb->ki_filp;
 	ssize_t rc;
 	size_t len, cur_len;
 	ssize_t total_read = 0;
-	loff_t offset = pos;
+	loff_t offset = iocb->ki_pos;
 	unsigned int npages;
 	struct cifs_sb_info *cifs_sb;
 	struct cifs_tcon *tcon;
 	struct cifsFileInfo *open_file;
 	struct cifs_readdata *rdata, *tmp;
 	struct list_head rdata_list;
-	struct iov_iter to;
 	pid_t pid;
 
-	if (!nr_segs)
-		return 0;
-
-	len = iov_length(iov, nr_segs);
+	len = iov_iter_count(to);
 	if (!len)
 		return 0;
 
-	iov_iter_init(&to, iov, nr_segs, len, 0);
-
 	INIT_LIST_HEAD(&rdata_list);
 	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 	open_file = file->private_data;
@@ -2914,7 +2902,7 @@ error:
 	if (!list_empty(&rdata_list))
 		rc = 0;
 
-	len = iov_iter_count(&to);
+	len = iov_iter_count(to);
 	/* the loop below should proceed in the order of increasing offsets */
 	list_for_each_entry_safe(rdata, tmp, &rdata_list, list) {
 	again:
@@ -2931,7 +2919,7 @@ error:
 					goto again;
 				}
 			} else {
-				rc = cifs_readdata_to_iov(rdata, &to);
+				rc = cifs_readdata_to_iov(rdata, to);
 			}
 
 		}
@@ -2939,7 +2927,7 @@ error:
 		kref_put(&rdata->refcount, cifs_uncached_readdata_release);
 	}
 
-	total_read = len - iov_iter_count(&to);
+	total_read = len - iov_iter_count(to);
 
 	cifs_stats_bytes_read(tcon, total_read);
 
@@ -2948,15 +2936,14 @@ error:
 		rc = 0;
 
 	if (total_read) {
-		iocb->ki_pos = pos + total_read;
+		iocb->ki_pos += total_read;
 		return total_read;
 	}
 	return rc;
 }
 
 ssize_t
-cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
-		  unsigned long nr_segs, loff_t pos)
+cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
@@ -2975,22 +2962,22 @@ cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
 	 * pos+len-1.
 	 */
 	if (!CIFS_CACHE_READ(cinode))
-		return cifs_user_readv(iocb, iov, nr_segs, pos);
+		return cifs_user_readv(iocb, to);
 
 	if (cap_unix(tcon->ses) &&
 	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
 	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
-		return generic_file_aio_read(iocb, iov, nr_segs, pos);
+		return generic_file_read_iter(iocb, to);
 
 	/*
 	 * We need to hold the sem to be sure nobody modifies lock list
 	 * with a brlock that prevents reading.
 	 */
 	down_read(&cinode->lock_sem);
-	if (!cifs_find_lock_conflict(cfile, pos, iov_length(iov, nr_segs),
+	if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
 				     tcon->ses->server->vals->shared_lock_type,
 				     NULL, CIFS_READ_OP))
-		rc = generic_file_aio_read(iocb, iov, nr_segs, pos);
+		rc = generic_file_read_iter(iocb, to);
 	up_read(&cinode->lock_sem);
 	return rc;
 }
@@ -3703,8 +3690,8 @@ void cifs_oplock_break(struct work_struct *work)
  * Direct IO is not yet supported in the cached mode. 
  */
 static ssize_t
-cifs_direct_io(int rw, struct kiocb *iocb, const struct iovec *iov,
-               loff_t pos, unsigned long nr_segs)
+cifs_direct_io(int rw, struct kiocb *iocb, struct iov_iter *iter,
+               loff_t pos)
 {
         /*
          * FIXME