5 files changed, 47 insertions, 4 deletions

diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index 514e44983a8e..12a147c9f87f 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -189,6 +189,8 @@ fsync_mode=%s          Control the policy of fsync. Currently supports "posix"
                        fsync will be heavy and behaves in line with xfs, ext4
                        and btrfs, where xfstest generic/342 will pass, but the
                        performance will regress.
+test_dummy_encryption  Enable dummy encryption, which provides a fake fscrypt
+                       context. The fake fscrypt context is used by xfstests.
 
 ================================================================================
 DEBUGFS ENTRIES
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 9a0d103b5052..fe661274ff10 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -361,6 +361,7 @@ struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
                         struct page *dpage)
 {
         struct page *page;
+        int dummy_encrypt = DUMMY_ENCRYPTION_ENABLED(F2FS_I_SB(dir));
         int err;
 
         if (is_inode_flag_set(inode, FI_NEW_INODE)) {
@@ -387,7 +388,8 @@ struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
                 if (err)
                         goto put_error;
 
-                if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) {
+                if ((f2fs_encrypted_inode(dir) || dummy_encrypt) &&
+                                        f2fs_may_encrypt(inode)) {
                         err = fscrypt_inherit_context(dir, inode, page, false);
                         if (err)
                                 goto put_error;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index c0d74ff9a6d7..191ee5718369 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -133,6 +133,7 @@ struct f2fs_mount_info {
         int whint_mode;
         int alloc_mode;                 /* segment allocation policy */
         int fsync_mode;                 /* fsync policy */
+        bool test_dummy_encryption;     /* test dummy encryption */
 };
 
 #define F2FS_FEATURE_ENCRYPT            0x0001
@@ -1077,6 +1078,13 @@ enum fsync_mode {
         FSYNC_MODE_STRICT,      /* fsync behaves in line with ext4 */
 };
 
+#ifdef CONFIG_F2FS_FS_ENCRYPTION
+#define DUMMY_ENCRYPTION_ENABLED(sbi) \
+                        (unlikely(F2FS_OPTION(sbi).test_dummy_encryption))
+#else
+#define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
+#endif
+
 struct f2fs_sb_info {
         struct super_block *sb;                 /* pointer to VFS super block */
         struct proc_dir_entry *s_proc;          /* proc entry */
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index f4ae46282eef..d5098efe577c 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -78,7 +78,8 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
         set_inode_flag(inode, FI_NEW_INODE);
 
         /* If the directory encrypted, then we should encrypt the inode. */
-        if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode))
+        if ((f2fs_encrypted_inode(dir) || DUMMY_ENCRYPTION_ENABLED(sbi)) &&
+                                f2fs_may_encrypt(inode))
                 f2fs_set_encrypted_inode(inode);
 
         if (f2fs_sb_has_extra_attr(sbi->sb)) {
@@ -787,10 +788,12 @@ out:
 
 static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
-        if (unlikely(f2fs_cp_error(F2FS_I_SB(dir))))
+        struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
+
+        if (unlikely(f2fs_cp_error(sbi)))
                 return -EIO;
 
-        if (f2fs_encrypted_inode(dir)) {
+        if (f2fs_encrypted_inode(dir) || DUMMY_ENCRYPTION_ENABLED(sbi)) {
                 int err = fscrypt_get_encryption_info(dir);
                 if (err)
                         return err;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index dcdae3f932e2..98b2c7ff1804 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -132,6 +132,7 @@ enum {
         Opt_whint,
         Opt_alloc,
         Opt_fsync,
+        Opt_test_dummy_encryption,
         Opt_err,
 };
 
@@ -188,6 +189,7 @@ static match_table_t f2fs_tokens = {
         {Opt_whint, "whint_mode=%s"},
         {Opt_alloc, "alloc_mode=%s"},
         {Opt_fsync, "fsync_mode=%s"},
+        {Opt_test_dummy_encryption, "test_dummy_encryption"},
         {Opt_err, NULL},
 };
 
@@ -744,6 +746,21 @@ static int parse_options(struct super_block *sb, char *options)
                         }
                         kfree(name);
                         break;
+                case Opt_test_dummy_encryption:
+#ifdef CONFIG_F2FS_FS_ENCRYPTION
+                        if (!f2fs_sb_has_encrypt(sb)) {
+                                f2fs_msg(sb, KERN_ERR, "Encrypt feature is off");
+                                return -EINVAL;
+                        }
+
+                        F2FS_OPTION(sbi).test_dummy_encryption = true;
+                        f2fs_msg(sb, KERN_INFO,
+                                        "Test dummy encryption mode enabled");
+#else
+                        f2fs_msg(sb, KERN_INFO,
+                                        "Test dummy encryption mount option ignored");
+#endif
+                        break;
                 default:
                         f2fs_msg(sb, KERN_ERR,
                                 "Unrecognized mount option \"%s\" or missing value",
@@ -1314,6 +1331,10 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
                 seq_printf(seq, ",whint_mode=%s", "user-based");
         else if (F2FS_OPTION(sbi).whint_mode == WHINT_MODE_FS)
                 seq_printf(seq, ",whint_mode=%s", "fs-based");
+#ifdef CONFIG_F2FS_FS_ENCRYPTION
+        if (F2FS_OPTION(sbi).test_dummy_encryption)
+                seq_puts(seq, ",test_dummy_encryption");
+#endif
 
         if (F2FS_OPTION(sbi).alloc_mode == ALLOC_MODE_DEFAULT)
                 seq_printf(seq, ",alloc_mode=%s", "default");
@@ -1335,6 +1356,7 @@ static void default_options(struct f2fs_sb_info *sbi)
         F2FS_OPTION(sbi).whint_mode = WHINT_MODE_OFF;
         F2FS_OPTION(sbi).alloc_mode = ALLOC_MODE_DEFAULT;
         F2FS_OPTION(sbi).fsync_mode = FSYNC_MODE_POSIX;
+        F2FS_OPTION(sbi).test_dummy_encryption = false;
         sbi->readdir_ra = 1;
 
         set_opt(sbi, BG_GC);
@@ -1908,6 +1930,11 @@ static int f2fs_set_context(struct inode *inode, const void *ctx, size_t len,
                                 ctx, len, fs_data, XATTR_CREATE);
 }
 
+static bool f2fs_dummy_context(struct inode *inode)
+{
+        return DUMMY_ENCRYPTION_ENABLED(F2FS_I_SB(inode));
+}
+
 static unsigned f2fs_max_namelen(struct inode *inode)
 {
         return S_ISLNK(inode->i_mode) ?
@@ -1918,6 +1945,7 @@ static const struct fscrypt_operations f2fs_cryptops = {
         .key_prefix     = "f2fs:",
         .get_context    = f2fs_get_context,
         .set_context    = f2fs_set_context,
+        .dummy_context  = f2fs_dummy_context,
         .empty_dir      = f2fs_empty_dir,
         .max_namelen    = f2fs_max_namelen,
 };