f2fs: refactor f2fs_convert_inline_data

Change log from v1:
 o handle NULL pointer of grab_cache_page_write_begin() pointed by Chao Yu.

This patch refactors f2fs_convert_inline_data to check a couple of conditions
internally for deciding whether it needs to convert inline_data or not.

So, the new f2fs_convert_inline_data initially checks:
1) f2fs_has_inline_data(), and
2) the data size to be changed.

If the inode has inline_data but the size to fill is less than MAX_INLINE_DATA,
then we don't need to convert the inline_data with data allocation.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/data.c

@@ -906,21 +906,17 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
 
 	f2fs_balance_fs(sbi);
 repeat:
+	err = f2fs_convert_inline_data(inode, pos + len);
+	if (err)
+		return err;
+
 	page = grab_cache_page_write_begin(mapping, index, flags);
 	if (!page)
 		return -ENOMEM;
 	*pagep = page;
 
-	if ((pos + len) < MAX_INLINE_DATA) {
-		if (f2fs_has_inline_data(inode))
-			goto inline_data;
-	} else if (f2fs_has_inline_data(inode)) {
-		err = f2fs_convert_inline_data(inode, page, flags);
-		if (err) {
-			f2fs_put_page(page, 1);
-			return err;
-		}
-	}
+	if (f2fs_has_inline_data(inode) && (pos + len) <= MAX_INLINE_DATA)
+		goto inline_data;
 
 	f2fs_lock_op(sbi);
 	set_new_dnode(&dn, inode, NULL, NULL, 0);

fs/f2fs/f2fs.h

@@ -1302,6 +1302,6 @@ extern const struct inode_operations f2fs_special_inode_operations;
 inline int f2fs_has_inline_data(struct inode *);
 bool f2fs_may_inline(struct inode *);
 int f2fs_read_inline_data(struct inode *, struct page *);
-int f2fs_convert_inline_data(struct inode *, struct page *, unsigned);
+int f2fs_convert_inline_data(struct inode *, pgoff_t);
 int f2fs_write_inline_data(struct inode *, struct page *, unsigned int);
 #endif

fs/f2fs/file.c

@@ -370,17 +370,12 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
 
 	if ((attr->ia_valid & ATTR_SIZE) &&
 			attr->ia_size != i_size_read(inode)) {
-		if (f2fs_has_inline_data(inode) &&
-				(attr->ia_size > MAX_INLINE_DATA)) {
-			unsigned flags = AOP_FLAG_NOFS;
-			err = f2fs_convert_inline_data(inode, NULL, flags);
-			if (err)
-				return err;
-		}
+		err = f2fs_convert_inline_data(inode, attr->ia_size);
+		if (err)
+			return err;
 
 		truncate_setsize(inode, attr->ia_size);
-		if (!f2fs_has_inline_data(inode))
-			f2fs_truncate(inode);
+		f2fs_truncate(inode);
 		f2fs_balance_fs(F2FS_SB(inode->i_sb));
 	}
 
@@ -462,7 +457,7 @@ static int punch_hole(struct inode *inode, loff_t offset, loff_t len)
 	loff_t off_start, off_end;
 	int ret = 0;
 
-	ret = f2fs_convert_inline_data(inode, NULL, AOP_FLAG_NOFS);
+	ret = f2fs_convert_inline_data(inode, MAX_INLINE_DATA + 1);
 	if (ret)
 		return ret;
 
@@ -512,16 +507,14 @@ static int expand_inode_data(struct inode *inode, loff_t offset,
 	loff_t off_start, off_end;
 	int ret = 0;
 
-	if (f2fs_has_inline_data(inode) && (offset + len > MAX_INLINE_DATA)) {
-		ret = f2fs_convert_inline_data(inode, NULL, AOP_FLAG_NOFS);
-		if (ret)
-			return ret;
-	}
-
 	ret = inode_newsize_ok(inode, (len + offset));
 	if (ret)
 		return ret;
 
+	ret = f2fs_convert_inline_data(inode, offset + len);
+	if (ret)
+		return ret;
+
 	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
 	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;
 

fs/f2fs/inline.c

@@ -101,6 +101,7 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
 	dst_addr = kmap(page);
 	memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
 	kunmap(page);
+	SetPageUptodate(page);
 
 	/* write data page to try to make data consistent */
 	set_page_writeback(page);
@@ -120,25 +121,22 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
 	return err;
 }
 
-int f2fs_convert_inline_data(struct inode *inode,
-			     struct page *p, unsigned flags)
+int f2fs_convert_inline_data(struct inode *inode, pgoff_t to_size)
 {
-	int err;
 	struct page *page;
+	int err;
 
-	if (!p || p->index) {
-		page = grab_cache_page_write_begin(inode->i_mapping, 0, flags);
-		if (IS_ERR(page))
-			return PTR_ERR(page);
-	} else {
-		page = p;
-	}
-
-	err = __f2fs_convert_inline_data(inode, page);
+	if (!f2fs_has_inline_data(inode))
+		return 0;
+	else if (to_size <= MAX_INLINE_DATA)
+		return 0;
 
-	if (!p || p->index)
-		f2fs_put_page(page, 1);
+	page = grab_cache_page_write_begin(inode->i_mapping, 0, AOP_FLAG_NOFS);
+	if (!page)
+		return -ENOMEM;
 
+	err = __f2fs_convert_inline_data(inode, page);
+	f2fs_put_page(page, 1);
 	return err;
 }