Merge tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs update from Miklos Szeredi:

 - Copy up immutable/append/sync/noatime attributes (Amir Goldstein)

 - Improve performance by enabling RCU lookup.

 - Misc fixes and improvements

The reason this touches so many files is that the ->get_acl() method now
gets a "bool rcu" argument.  The ->get_acl() API was updated based on
comments from Al and Linus:

Link: https://lore.kernel.org/linux-fsdevel/CAJfpeguQxpd6Wgc0Jd3ks77zcsAv_bn0q17L3VNnnmPKu11t8A@mail.gmail.com/

* tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: enable RCU'd ->get_acl()
  vfs: add rcu argument to ->get_acl() callback
  ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup()
  ovl: use kvalloc in xattr copy-up
  ovl: update ctime when changing fileattr
  ovl: skip checking lower file's i_writecount on truncate
  ovl: relax lookup error on mismatch origin ftype
  ovl: do not set overlay.opaque for new directories
  ovl: add ovl_allow_offline_changes() helper
  ovl: disable decoding null uuid with redirect_dir
  ovl: consistent behavior for immutable/append-only inodes
  ovl: copy up sync/noatime fileattr flags
  ovl: pass ovl_fs to ovl_check_setxattr()
  fs: add generic helper for filling statx attribute flags

3 files changed, 13 insertions, 2 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1c01f9f2b574..a6074cdb7798 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -588,6 +588,11 @@ static inline void mapping_allow_writable(struct address_space *mapping)
 
 struct posix_acl;
 #define ACL_NOT_CACHED ((void *)(-1))
+/*
+ * ACL_DONT_CACHE is for stacked filesystems, that rely on underlying fs to
+ * cache the ACL.  This also means that ->get_acl() can be called in RCU mode
+ * with the LOOKUP_RCU flag.
+ */
 #define ACL_DONT_CACHE ((void *)(-3))
 
 static inline struct posix_acl *
@@ -2109,7 +2114,7 @@ struct inode_operations {
 	struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
 	const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
 	int (*permission) (struct user_namespace *, struct inode *, int);
-	struct posix_acl * (*get_acl)(struct inode *, int);
+	struct posix_acl * (*get_acl)(struct inode *, int, bool);
 
 	int (*readlink) (struct dentry *, char __user *,int);
 
@@ -3314,6 +3319,7 @@ extern int page_symlink(struct inode *inode, const char *symname, int len);
 extern const struct inode_operations page_symlink_inode_operations;
 extern void kfree_link(void *);
 void generic_fillattr(struct user_namespace *, struct inode *, struct kstat *);
+void generic_fill_statx_attr(struct inode *inode, struct kstat *stat);
 extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
 extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
 void __inode_add_bytes(struct inode *inode, loff_t bytes);
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 307094ebb88c..b65c877d92b8 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -72,6 +72,8 @@ extern struct posix_acl *get_posix_acl(struct inode *, int);
 extern int set_posix_acl(struct user_namespace *, struct inode *, int,
 			 struct posix_acl *);
 
+struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type);
+
 #ifdef CONFIG_FS_POSIX_ACL
 int posix_acl_chmod(struct user_namespace *, struct inode *, umode_t);
 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **,
@@ -84,7 +86,6 @@ extern int simple_set_acl(struct user_namespace *, struct inode *,
 extern int simple_acl_create(struct inode *, struct inode *);
 
 struct posix_acl *get_cached_acl(struct inode *inode, int type);
-struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type);
 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl);
 void forget_cached_acl(struct inode *inode, int type);
 void forget_all_cached_acls(struct inode *inode);
diff --git a/include/linux/stat.h b/include/linux/stat.h
index fff27e603814..7df06931f25d 100644
--- a/include/linux/stat.h
+++ b/include/linux/stat.h
@@ -34,6 +34,10 @@ struct kstat {
 	 STATX_ATTR_ENCRYPTED |				\
 	 STATX_ATTR_VERITY				\
 	 )/* Attrs corresponding to FS_*_FL flags */
+#define KSTAT_ATTR_VFS_FLAGS				\
+	(STATX_ATTR_IMMUTABLE |				\
+	 STATX_ATTR_APPEND				\
+	 ) /* Attrs corresponding to S_* flags that are enforced by the VFS */
 	u64		ino;
 	dev_t		dev;
 	dev_t		rdev;