Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index f622f74..0d1a53d 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -100,6 +100,35 @@
 	dentry->d_flags &= ~DCACHE_ENCRYPTED_NAME;
 }
 
+/**
+ * fscrypt_is_nokey_name() - test whether a dentry is a no-key name
+ * @dentry: the dentry to check
+ *
+ * This returns true if the dentry is a no-key dentry.  A no-key dentry is a
+ * dentry that was created in an encrypted directory that hasn't had its
+ * encryption key added yet.  Such dentries may be either positive or negative.
+ *
+ * When a filesystem is asked to create a new filename in an encrypted directory
+ * and the new filename's dentry is a no-key dentry, it must fail the operation
+ * with ENOKEY.  This includes ->create(), ->mkdir(), ->mknod(), ->symlink(),
+ * ->rename(), and ->link().  (However, ->rename() and ->link() are already
+ * handled by fscrypt_prepare_rename() and fscrypt_prepare_link().)
+ *
+ * This is necessary because creating a filename requires the directory's
+ * encryption key, but just checking for the key on the directory inode during
+ * the final filesystem operation doesn't guarantee that the key was available
+ * during the preceding dentry lookup.  And the key must have already been
+ * available during the dentry lookup in order for it to have been checked
+ * whether the filename already exists in the directory and for the new file's
+ * dentry not to be invalidated due to it incorrectly having the no-key flag.
+ *
+ * Return: %true if the dentry is a no-key name
+ */
+static inline bool fscrypt_is_nokey_name(const struct dentry *dentry)
+{
+	return dentry->d_flags & DCACHE_ENCRYPTED_NAME;
+}
+
 /* crypto.c */
 extern void fscrypt_enqueue_decrypt_work(struct work_struct *);
 extern struct fscrypt_ctx *fscrypt_get_ctx(gfp_t);
@@ -269,6 +298,7 @@
 extern const char *fscrypt_get_symlink(struct inode *inode, const void *caddr,
 				       unsigned int max_size,
 				       struct delayed_call *done);
+int fscrypt_symlink_getattr(const struct path *path, struct kstat *stat);
 static inline void fscrypt_set_ops(struct super_block *sb,
 				   const struct fscrypt_operations *s_cop)
 {
@@ -290,6 +320,11 @@
 {
 }
 
+static inline bool fscrypt_is_nokey_name(const struct dentry *dentry)
+{
+	return false;
+}
+
 /* crypto.c */
 static inline void fscrypt_enqueue_decrypt_work(struct work_struct *work)
 {
@@ -551,6 +586,12 @@
 	return ERR_PTR(-EOPNOTSUPP);
 }
 
+static inline int fscrypt_symlink_getattr(const struct path *path,
+					  struct kstat *stat)
+{
+	return -EOPNOTSUPP;
+}
+
 static inline void fscrypt_set_ops(struct super_block *sb,
 				   const struct fscrypt_operations *s_cop)
 {