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

…nel/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

Documentation/filesystems/locking.rst

@@ -70,7 +70,7 @@ prototypes::
 	const char *(*get_link) (struct dentry *, struct inode *, struct delayed_call *);
 	void (*truncate) (struct inode *);
 	int (*permission) (struct inode *, int, unsigned int);
-	int (*get_acl)(struct inode *, int);
+	struct posix_acl * (*get_acl)(struct inode *, int, bool);
 	int (*setattr) (struct dentry *, struct iattr *);
 	int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
 	ssize_t (*listxattr) (struct dentry *, char *, size_t);

Documentation/filesystems/overlayfs.rst

@@ -427,6 +427,9 @@ b) If a file residing on a lower layer is opened for read-only and then
 memory mapped with MAP_SHARED, then subsequent changes to the file are not
 reflected in the memory mapping.
 
+c) If a file residing on a lower layer is being executed, then opening that
+file for write or truncating the file will not be denied with ETXTBSY.
+
 The following options allow overlayfs to act more like a standards
 compliant filesystem:
 

Documentation/filesystems/vfs.rst

@@ -432,7 +432,7 @@ As of kernel 2.6.22, the following members are defined:
 		const char *(*get_link) (struct dentry *, struct inode *,
 					 struct delayed_call *);
 		int (*permission) (struct user_namespace *, struct inode *, int);
-		int (*get_acl)(struct inode *, int);
+		struct posix_acl * (*get_acl)(struct inode *, int, bool);
 		int (*setattr) (struct user_namespace *, struct dentry *, struct iattr *);
 		int (*getattr) (struct user_namespace *, const struct path *, struct kstat *, u32, unsigned int);
 		ssize_t (*listxattr) (struct dentry *, char *, size_t);

fs/9p/acl.c

@@ -97,10 +97,13 @@ static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
 	return acl;
 }
 
-struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
+struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct v9fs_session_info *v9ses;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	v9ses = v9fs_inode2v9ses(inode);
 	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
 			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {

fs/9p/acl.h

@@ -16,7 +16,7 @@
 
 #ifdef CONFIG_9P_FS_POSIX_ACL
 extern int v9fs_get_acl(struct inode *, struct p9_fid *);
-extern struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type);
+extern struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type, bool rcu);
 extern int v9fs_acl_chmod(struct inode *, struct p9_fid *);
 extern int v9fs_set_create_acl(struct inode *, struct p9_fid *,
 			       struct posix_acl *, struct posix_acl *);

fs/bad_inode.c

@@ -121,7 +121,7 @@ static const char *bad_inode_get_link(struct dentry *dentry,
 	return ERR_PTR(-EIO);
 }
 
-static struct posix_acl *bad_inode_get_acl(struct inode *inode, int type)
+static struct posix_acl *bad_inode_get_acl(struct inode *inode, int type, bool rcu)
 {
 	return ERR_PTR(-EIO);
 }

fs/btrfs/acl.c

@@ -16,13 +16,16 @@
 #include "btrfs_inode.h"
 #include "xattr.h"
 
-struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
+struct posix_acl *btrfs_get_acl(struct inode *inode, int type, bool rcu)
 {
 	int size;
 	const char *name;
 	char *value = NULL;
 	struct posix_acl *acl;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name = XATTR_NAME_POSIX_ACL_ACCESS;

fs/btrfs/ctree.h

@@ -3706,7 +3706,7 @@ static inline int __btrfs_fs_compat_ro(struct btrfs_fs_info *fs_info, u64 flag)
 
 /* acl.c */
 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
-struct posix_acl *btrfs_get_acl(struct inode *inode, int type);
+struct posix_acl *btrfs_get_acl(struct inode *inode, int type, bool rcu);
 int btrfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		  struct posix_acl *acl, int type);
 int btrfs_init_acl(struct btrfs_trans_handle *trans,

fs/ceph/acl.c

@@ -29,14 +29,17 @@ static inline void ceph_set_cached_acl(struct inode *inode,
 	spin_unlock(&ci->i_ceph_lock);
 }
 
-struct posix_acl *ceph_get_acl(struct inode *inode, int type)
+struct posix_acl *ceph_get_acl(struct inode *inode, int type, bool rcu)
 {
 	int size;
 	unsigned int retry_cnt = 0;
 	const char *name;
 	char *value = NULL;
 	struct posix_acl *acl;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name = XATTR_NAME_POSIX_ACL_ACCESS;

fs/ceph/super.h

@@ -1088,7 +1088,7 @@ void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx);
 /* acl.c */
 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 
-struct posix_acl *ceph_get_acl(struct inode *, int);
+struct posix_acl *ceph_get_acl(struct inode *, int, bool);
 int ceph_set_acl(struct user_namespace *mnt_userns,
 		 struct inode *inode, struct posix_acl *acl, int type);
 int ceph_pre_init_acls(struct inode *dir, umode_t *mode,

fs/erofs/xattr.c

@@ -673,12 +673,15 @@ ssize_t erofs_listxattr(struct dentry *dentry,
 }
 
 #ifdef CONFIG_EROFS_FS_POSIX_ACL
-struct posix_acl *erofs_get_acl(struct inode *inode, int type)
+struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct posix_acl *acl;
 	int prefix, rc;
 	char *value = NULL;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS;

fs/erofs/xattr.h

@@ -80,7 +80,7 @@ static inline int erofs_getxattr(struct inode *inode, int index,
 #endif	/* !CONFIG_EROFS_FS_XATTR */
 
 #ifdef CONFIG_EROFS_FS_POSIX_ACL
-struct posix_acl *erofs_get_acl(struct inode *inode, int type);
+struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu);
 #else
 #define erofs_get_acl	(NULL)
 #endif

fs/ext2/acl.c

@@ -141,13 +141,16 @@ ext2_acl_to_disk(const struct posix_acl *acl, size_t *size)
  * inode->i_mutex: don't care
  */
 struct posix_acl *
-ext2_get_acl(struct inode *inode, int type)
+ext2_get_acl(struct inode *inode, int type, bool rcu)
 {
 	int name_index;
 	char *value = NULL;
 	struct posix_acl *acl;
 	int retval;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name_index = EXT2_XATTR_INDEX_POSIX_ACL_ACCESS;

fs/ext2/acl.h

@@ -55,7 +55,7 @@ static inline int ext2_acl_count(size_t size)
 #ifdef CONFIG_EXT2_FS_POSIX_ACL
 
 /* acl.c */
-extern struct posix_acl *ext2_get_acl(struct inode *inode, int type);
+extern struct posix_acl *ext2_get_acl(struct inode *inode, int type, bool rcu);
 extern int ext2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 			struct posix_acl *acl, int type);
 extern int ext2_init_acl (struct inode *, struct inode *);

fs/ext4/acl.c

@@ -142,13 +142,16 @@ ext4_acl_to_disk(const struct posix_acl *acl, size_t *size)
  * inode->i_mutex: don't care
  */
 struct posix_acl *
-ext4_get_acl(struct inode *inode, int type)
+ext4_get_acl(struct inode *inode, int type, bool rcu)
 {
 	int name_index;
 	char *value = NULL;
 	struct posix_acl *acl;
 	int retval;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS;

fs/ext4/acl.h

@@ -55,7 +55,7 @@ static inline int ext4_acl_count(size_t size)
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 
 /* acl.c */
-struct posix_acl *ext4_get_acl(struct inode *inode, int type);
+struct posix_acl *ext4_get_acl(struct inode *inode, int type, bool rcu);
 int ext4_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		 struct posix_acl *acl, int type);
 extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);

fs/f2fs/acl.c

@@ -196,8 +196,11 @@ static struct posix_acl *__f2fs_get_acl(struct inode *inode, int type,
 	return acl;
 }
 
-struct posix_acl *f2fs_get_acl(struct inode *inode, int type)
+struct posix_acl *f2fs_get_acl(struct inode *inode, int type, bool rcu)
 {
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	return __f2fs_get_acl(inode, type, NULL);
 }
 

fs/f2fs/acl.h

@@ -33,7 +33,7 @@ struct f2fs_acl_header {
 
 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 
-extern struct posix_acl *f2fs_get_acl(struct inode *, int);
+extern struct posix_acl *f2fs_get_acl(struct inode *, int, bool);
 extern int f2fs_set_acl(struct user_namespace *, struct inode *,
 			struct posix_acl *, int);
 extern int f2fs_init_acl(struct inode *, struct inode *, struct page *,

fs/fuse/acl.c

@@ -11,14 +11,17 @@
 #include <linux/posix_acl.h>
 #include <linux/posix_acl_xattr.h>
 
-struct posix_acl *fuse_get_acl(struct inode *inode, int type)
+struct posix_acl *fuse_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	int size;
 	const char *name;
 	void *value = NULL;
 	struct posix_acl *acl;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	if (fuse_is_bad(inode))
 		return ERR_PTR(-EIO);
 

fs/fuse/fuse_i.h

@@ -1209,7 +1209,7 @@ extern const struct xattr_handler *fuse_acl_xattr_handlers[];
 extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
 
 struct posix_acl;
-struct posix_acl *fuse_get_acl(struct inode *inode, int type);
+struct posix_acl *fuse_get_acl(struct inode *inode, int type, bool rcu);
 int fuse_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		 struct posix_acl *acl, int type);
 

fs/gfs2/acl.c

@@ -57,13 +57,16 @@ static struct posix_acl *__gfs2_get_acl(struct inode *inode, int type)
 	return acl;
 }
 
-struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
+struct posix_acl *gfs2_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder gh;
 	bool need_unlock = false;
 	struct posix_acl *acl;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 		int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 					     LM_FLAG_ANY, &gh);

fs/gfs2/acl.h

@@ -11,7 +11,7 @@
 
 #define GFS2_ACL_MAX_ENTRIES(sdp) ((300 << (sdp)->sd_sb.sb_bsize_shift) >> 12)
 
-extern struct posix_acl *gfs2_get_acl(struct inode *inode, int type);
+extern struct posix_acl *gfs2_get_acl(struct inode *inode, int type, bool rcu);
 extern int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
 extern int gfs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 			struct posix_acl *acl, int type);

fs/jffs2/acl.c

@@ -173,12 +173,15 @@ static void *jffs2_acl_to_medium(const struct posix_acl *acl, size_t *size)
 	return ERR_PTR(-EINVAL);
 }
 
-struct posix_acl *jffs2_get_acl(struct inode *inode, int type)
+struct posix_acl *jffs2_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct posix_acl *acl;
 	char *value = NULL;
 	int rc, xprefix;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		xprefix = JFFS2_XPREFIX_ACL_ACCESS;

fs/jffs2/acl.h

@@ -27,7 +27,7 @@ struct jffs2_acl_header {
 
 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
 
-struct posix_acl *jffs2_get_acl(struct inode *inode, int type);
+struct posix_acl *jffs2_get_acl(struct inode *inode, int type, bool rcu);
 int jffs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		  struct posix_acl *acl, int type);
 extern int jffs2_init_acl_pre(struct inode *, struct inode *, umode_t *);

fs/jfs/acl.c

@@ -14,13 +14,16 @@
 #include "jfs_xattr.h"
 #include "jfs_acl.h"
 
-struct posix_acl *jfs_get_acl(struct inode *inode, int type)
+struct posix_acl *jfs_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct posix_acl *acl;
 	char *ea_name;
 	int size;
 	char *value = NULL;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch(type) {
 		case ACL_TYPE_ACCESS:
 			ea_name = XATTR_NAME_POSIX_ACL_ACCESS;

fs/jfs/jfs_acl.h

@@ -7,7 +7,7 @@
 
 #ifdef CONFIG_JFS_POSIX_ACL
 
-struct posix_acl *jfs_get_acl(struct inode *inode, int type);
+struct posix_acl *jfs_get_acl(struct inode *inode, int type, bool rcu);
 int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		struct posix_acl *acl, int type);
 int jfs_init_acl(tid_t, struct inode *, struct inode *);

fs/nfs/nfs3_fs.h

@@ -11,7 +11,7 @@
  * nfs3acl.c
  */
 #ifdef CONFIG_NFS_V3_ACL
-extern struct posix_acl *nfs3_get_acl(struct inode *inode, int type);
+extern struct posix_acl *nfs3_get_acl(struct inode *inode, int type, bool rcu);
 extern int nfs3_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 			struct posix_acl *acl, int type);
 extern int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,

fs/nfs/nfs3acl.c

@@ -44,7 +44,7 @@ static void nfs3_abort_get_acl(struct posix_acl **p)
 	cmpxchg(p, sentinel, ACL_NOT_CACHED);
 }
 
-struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
+struct posix_acl *nfs3_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
 	struct page *pages[NFSACL_MAXPAGES] = { };
@@ -62,6 +62,9 @@ struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
 	};
 	int status, count;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
 		return ERR_PTR(-EOPNOTSUPP);
 

fs/ocfs2/acl.c

@@ -289,14 +289,17 @@ int ocfs2_iop_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 	return status;
 }
 
-struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type)
+struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct ocfs2_super *osb;
 	struct buffer_head *di_bh = NULL;
 	struct posix_acl *acl;
 	int had_lock;
 	struct ocfs2_lock_holder oh;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	osb = OCFS2_SB(inode->i_sb);
 	if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
 		return NULL;

fs/ocfs2/acl.h

@@ -16,7 +16,7 @@ struct ocfs2_acl_entry {
 	__le32 e_id;
 };
 
-struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type);
+struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type, bool rcu);
 int ocfs2_iop_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 		      struct posix_acl *acl, int type);
 extern int ocfs2_acl_chmod(struct inode *, struct buffer_head *);

fs/orangefs/acl.c

@@ -10,12 +10,15 @@
 #include "orangefs-bufmap.h"
 #include <linux/posix_acl_xattr.h>
 
-struct posix_acl *orangefs_get_acl(struct inode *inode, int type)
+struct posix_acl *orangefs_get_acl(struct inode *inode, int type, bool rcu)
 {
 	struct posix_acl *acl;
 	int ret;
 	char *key = NULL, *value = NULL;
 
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		key = XATTR_NAME_POSIX_ACL_ACCESS;