1 files changed, 55 insertions, 68 deletions

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index b202626391ff..7aca8944901d 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3249,6 +3249,32 @@ out_trace:
 	return retval;
 }
 
+static int ext4_init_symlink_block(handle_t *handle, struct inode *inode,
+				   struct fscrypt_str *disk_link)
+{
+	struct buffer_head *bh;
+	char *kaddr;
+	int err = 0;
+
+	bh = ext4_bread(handle, inode, 0, EXT4_GET_BLOCKS_CREATE);
+	if (IS_ERR(bh))
+		return PTR_ERR(bh);
+
+	BUFFER_TRACE(bh, "get_write_access");
+	err = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE);
+	if (err)
+		goto out;
+
+	kaddr = (char *)bh->b_data;
+	memcpy(kaddr, disk_link->name, disk_link->len);
+	inode->i_size = disk_link->len - 1;
+	EXT4_I(inode)->i_disksize = inode->i_size;
+	err = ext4_handle_dirty_metadata(handle, inode, bh);
+out:
+	brelse(bh);
+	return err;
+}
+
 static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 			struct dentry *dentry, const char *symname)
 {
@@ -3257,6 +3283,7 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 	int err, len = strlen(symname);
 	int credits;
 	struct fscrypt_str disk_link;
+	int retries = 0;
 
 	if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
 		return -EIO;
@@ -3270,26 +3297,15 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 	if (err)
 		return err;
 
-	if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
-		/*
-		 * For non-fast symlinks, we just allocate inode and put it on
-		 * orphan list in the first transaction => we need bitmap,
-		 * group descriptor, sb, inode block, quota blocks, and
-		 * possibly selinux xattr blocks.
-		 */
-		credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
-			  EXT4_XATTR_TRANS_BLOCKS;
-	} else {
-		/*
-		 * Fast symlink. We have to add entry to directory
-		 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
-		 * allocate new inode (bitmap, group descriptor, inode block,
-		 * quota blocks, sb is already counted in previous macros).
-		 */
-		credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
-			  EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
-	}
-
+	/*
+	 * EXT4_INDEX_EXTRA_TRANS_BLOCKS for addition of entry into the
+	 * directory. +3 for inode, inode bitmap, group descriptor allocation.
+	 * EXT4_DATA_TRANS_BLOCKS for the data block allocation and
+	 * modification.
+	 */
+	credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+		  EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
+retry:
 	inode = ext4_new_inode_start_handle(mnt_userns, dir, S_IFLNK|S_IRWXUGO,
 					    &dentry->d_name, 0, NULL,
 					    EXT4_HT_DIR, credits);
@@ -3297,7 +3313,8 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 	if (IS_ERR(inode)) {
 		if (handle)
 			ext4_journal_stop(handle);
-		return PTR_ERR(inode);
+		err = PTR_ERR(inode);
+		goto out_retry;
 	}
 
 	if (IS_ENCRYPTED(inode)) {
@@ -3305,74 +3322,44 @@ static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 		if (err)
 			goto err_drop_inode;
 		inode->i_op = &ext4_encrypted_symlink_inode_operations;
+	} else {
+		if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
+			inode->i_op = &ext4_symlink_inode_operations;
+		} else {
+			inode->i_op = &ext4_fast_symlink_inode_operations;
+			inode->i_link = (char *)&EXT4_I(inode)->i_data;
+		}
 	}
 
 	if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
-		if (!IS_ENCRYPTED(inode))
-			inode->i_op = &ext4_symlink_inode_operations;
-		inode_nohighmem(inode);
-		ext4_set_aops(inode);
-		/*
-		 * We cannot call page_symlink() with transaction started
-		 * because it calls into ext4_write_begin() which can wait
-		 * for transaction commit if we are running out of space
-		 * and thus we deadlock. So we have to stop transaction now
-		 * and restart it when symlink contents is written.
-		 *
-		 * To keep fs consistent in case of crash, we have to put inode
-		 * to orphan list in the mean time.
-		 */
-		drop_nlink(inode);
-		err = ext4_orphan_add(handle, inode);
-		if (handle)
-			ext4_journal_stop(handle);
-		handle = NULL;
-		if (err)
-			goto err_drop_inode;
-		err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
-		if (err)
-			goto err_drop_inode;
-		/*
-		 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
-		 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
-		 */
-		handle = ext4_journal_start(dir, EXT4_HT_DIR,
-				EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
-				EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
-		if (IS_ERR(handle)) {
-			err = PTR_ERR(handle);
-			handle = NULL;
-			goto err_drop_inode;
-		}
-		set_nlink(inode, 1);
-		err = ext4_orphan_del(handle, inode);
+		/* alloc symlink block and fill it */
+		err = ext4_init_symlink_block(handle, inode, &disk_link);
 		if (err)
 			goto err_drop_inode;
 	} else {
 		/* clear the extent format for fast symlink */
 		ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
-		if (!IS_ENCRYPTED(inode)) {
-			inode->i_op = &ext4_fast_symlink_inode_operations;
-			inode->i_link = (char *)&EXT4_I(inode)->i_data;
-		}
 		memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,
 		       disk_link.len);
 		inode->i_size = disk_link.len - 1;
+		EXT4_I(inode)->i_disksize = inode->i_size;
 	}
-	EXT4_I(inode)->i_disksize = inode->i_size;
 	err = ext4_add_nondir(handle, dentry, &inode);
 	if (handle)
 		ext4_journal_stop(handle);
 	iput(inode);
-	goto out_free_encrypted_link;
+	goto out_retry;
 
 err_drop_inode:
-	if (handle)
-		ext4_journal_stop(handle);
 	clear_nlink(inode);
+	ext4_orphan_add(handle, inode);
 	unlock_new_inode(inode);
+	if (handle)
+		ext4_journal_stop(handle);
 	iput(inode);
-out_free_encrypted_link:
+out_retry:
+	if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+		goto retry;
 	if (disk_link.name != (unsigned char *)symname)
 		kfree(disk_link.name);
 	return err;