Merge tag 'fuse-update-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse update from Miklos Szeredi:

 - Allow some write requests to proceed in parallel

 - Fix a performance problem with allow_sys_admin_access

 - Add a special kind of invalidation that doesn't immediately purge
   submounts

 - On revalidation treat the target of rename(RENAME_NOREPLACE) the same
   as open(O_EXCL)

 - Use type safe helpers for some mnt_userns transformations

* tag 'fuse-update-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: Rearrange fuse_allow_current_process checks
  fuse: allow non-extending parallel direct writes on the same file
  fuse: remove the unneeded result variable
  fuse: port to vfs{g,u}id_t and associated helpers
  fuse: Remove user_ns check for FUSE_DEV_IOC_CLONE
  fuse: always revalidate rename target dentry
  fuse: add "expire only" mode to FUSE_NOTIFY_INVAL_ENTRY
  fs/fuse: Replace kmap() with kmap_local_page()

1 files changed, 25 insertions, 18 deletions

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 25e6b0f7e73d..cd1a071b625a 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -214,7 +214,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
 	if (inode && fuse_is_bad(inode))
 		goto invalid;
 	else if (time_before64(fuse_dentry_time(entry), get_jiffies_64()) ||
-		 (flags & (LOOKUP_EXCL | LOOKUP_REVAL))) {
+		 (flags & (LOOKUP_EXCL | LOOKUP_REVAL | LOOKUP_RENAME_TARGET))) {
 		struct fuse_entry_out outarg;
 		FUSE_ARGS(args);
 		struct fuse_forget_link *forget;
@@ -1170,7 +1170,7 @@ int fuse_update_attributes(struct inode *inode, struct file *file, u32 mask)
 }
 
 int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
-			     u64 child_nodeid, struct qstr *name)
+			     u64 child_nodeid, struct qstr *name, u32 flags)
 {
 	int err = -ENOTDIR;
 	struct inode *parent;
@@ -1197,7 +1197,9 @@ int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
 		goto unlock;
 
 	fuse_dir_changed(parent);
-	fuse_invalidate_entry(entry);
+	if (!(flags & FUSE_EXPIRE_ONLY))
+		d_invalidate(entry);
+	fuse_invalidate_entry_cache(entry);
 
 	if (child_nodeid != 0 && d_really_is_positive(entry)) {
 		inode_lock(d_inode(entry));
@@ -1235,6 +1237,18 @@ int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
 	return err;
 }
 
+static inline bool fuse_permissible_uidgid(struct fuse_conn *fc)
+{
+	const struct cred *cred = current_cred();
+
+	return (uid_eq(cred->euid, fc->user_id) &&
+		uid_eq(cred->suid, fc->user_id) &&
+		uid_eq(cred->uid,  fc->user_id) &&
+		gid_eq(cred->egid, fc->group_id) &&
+		gid_eq(cred->sgid, fc->group_id) &&
+		gid_eq(cred->gid,  fc->group_id));
+}
+
 /*
  * Calling into a user-controlled filesystem gives the filesystem
  * daemon ptrace-like capabilities over the current process.  This
@@ -1248,26 +1262,19 @@ int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
  * for which the owner of the mount has ptrace privilege.  This
  * excludes processes started by other users, suid or sgid processes.
  */
-int fuse_allow_current_process(struct fuse_conn *fc)
+bool fuse_allow_current_process(struct fuse_conn *fc)
 {
-	const struct cred *cred;
-
-	if (allow_sys_admin_access && capable(CAP_SYS_ADMIN))
-		return 1;
+	bool allow;
 
 	if (fc->allow_other)
-		return current_in_userns(fc->user_ns);
+		allow = current_in_userns(fc->user_ns);
+	else
+		allow = fuse_permissible_uidgid(fc);
 
-	cred = current_cred();
-	if (uid_eq(cred->euid, fc->user_id) &&
-	    uid_eq(cred->suid, fc->user_id) &&
-	    uid_eq(cred->uid,  fc->user_id) &&
-	    gid_eq(cred->egid, fc->group_id) &&
-	    gid_eq(cred->sgid, fc->group_id) &&
-	    gid_eq(cred->gid,  fc->group_id))
-		return 1;
+	if (!allow && allow_sys_admin_access && capable(CAP_SYS_ADMIN))
+		allow = true;
 
-	return 0;
+	return allow;
 }
 
 static int fuse_access(struct inode *inode, int mask)