Merge tag 'vfs-6.15-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "Features:

   - Add CONFIG_DEBUG_VFS infrastucture:
      - Catch invalid modes in open
      - Use the new debug macros in inode_set_cached_link()
      - Use debug-only asserts around fd allocation and install

   - Place f_ref to 3rd cache line in struct file to resolve false
     sharing

Cleanups:

   - Start using anon_inode_getfile_fmode() helper in various places

   - Don't take f_lock during SEEK_CUR if exclusion is guaranteed by
     f_pos_lock

   - Add unlikely() to kcmp()

   - Remove legacy ->remount_fs method from ecryptfs after port to the
     new mount api

   - Remove invalidate_inodes() in favour of evict_inodes()

   - Simplify ep_busy_loopER by removing unused argument

   - Avoid mmap sem relocks when coredumping with many missing pages

   - Inline getname()

   - Inline new_inode_pseudo() and de-staticize alloc_inode()

   - Dodge an atomic in putname if ref == 1

   - Consistently deref the files table with rcu_dereference_raw()

   - Dedup handling of struct filename init and refcounts bumps

   - Use wq_has_sleeper() in end_dir_add()

   - Drop the lock trip around I_NEW wake up in evict()

   - Load the ->i_sb pointer once in inode_sb_list_{add,del}

   - Predict not reaching the limit in alloc_empty_file()

   - Tidy up do_sys_openat2() with likely/unlikely

   - Call inode_sb_list_add() outside of inode hash lock

   - Sort out fd allocation vs dup2 race commentary

   - Turn page_offset() into a wrapper around folio_pos()

   - Remove locking in exportfs around ->get_parent() call

   - try_lookup_one_len() does not need any locks in autofs

   - Fix return type of several functions from long to int in open

   - Fix return type of several functions from long to int in ioctls

  Fixes:

   - Fix watch queue accounting mismatch"

* tag 'vfs-6.15-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
  fs: sort out fd allocation vs dup2 race commentary, take 2
  fs: call inode_sb_list_add() outside of inode hash lock
  fs: tidy up do_sys_openat2() with likely/unlikely
  fs: predict not reaching the limit in alloc_empty_file()
  fs: load the ->i_sb pointer once in inode_sb_list_{add,del}
  fs: drop the lock trip around I_NEW wake up in evict()
  fs: use wq_has_sleeper() in end_dir_add()
  VFS/autofs: try_lookup_one_len() does not need any locks
  fs: dedup handling of struct filename init and refcounts bumps
  fs: consistently deref the files table with rcu_dereference_raw()
  exportfs: remove locking around ->get_parent() call.
  fs: use debug-only asserts around fd allocation and install
  fs: dodge an atomic in putname if ref == 1
  vfs: Remove invalidate_inodes()
  ecryptfs: remove NULL remount_fs from super_operations
  watch_queue: fix pipe accounting mismatch
  fs: place f_ref to 3rd cache line in struct file to resolve false sharing
  epoll: simplify ep_busy_loop by removing always 0 argument
  fs: Turn page_offset() into a wrapper around folio_pos()
  kcmp: improve performance adding an unlikely hint to task comparisons
  ...

3 files changed, 15 insertions, 8 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 9c853cde9abe..78fd876a5473 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2207,10 +2207,8 @@ __audit_reusename(const __user char *uptr)
 	list_for_each_entry(n, &context->names_list, list) {
 		if (!n->name)
 			continue;
-		if (n->name->uptr == uptr) {
-			atomic_inc(&n->name->refcnt);
-			return n->name;
-		}
+		if (n->name->uptr == uptr)
+			return refname(n->name);
 	}
 	return NULL;
 }
@@ -2237,7 +2235,7 @@ void __audit_getname(struct filename *name)
 	n->name = name;
 	n->name_len = AUDIT_NAME_FULL;
 	name->aname = n;
-	atomic_inc(&name->refcnt);
+	refname(name);
 }
 
 static inline int audit_copy_fcaps(struct audit_names *name,
@@ -2369,7 +2367,7 @@ out_alloc:
 		return;
 	if (name) {
 		n->name = name;
-		atomic_inc(&name->refcnt);
+		refname(name);
 	}
 
 out:
@@ -2496,7 +2494,7 @@ void __audit_inode_child(struct inode *parent,
 		if (found_parent) {
 			found_child->name = found_parent->name;
 			found_child->name_len = AUDIT_NAME_FULL;
-			atomic_inc(&found_child->name->refcnt);
+			refname(found_child->name);
 		}
 	}
 
diff --git a/kernel/kcmp.c b/kernel/kcmp.c
index 2c596851f8a9..7c1a65bd5f8d 100644
--- a/kernel/kcmp.c
+++ b/kernel/kcmp.c
@@ -145,7 +145,7 @@ SYSCALL_DEFINE5(kcmp, pid_t, pid1, pid_t, pid2, int, type,
 	 */
 	task1 = find_task_by_vpid(pid1);
 	task2 = find_task_by_vpid(pid2);
-	if (!task1 || !task2)
+	if (unlikely(!task1 || !task2))
 		goto err_no_task;
 
 	get_task_struct(task1);
diff --git a/kernel/watch_queue.c b/kernel/watch_queue.c
index 5267adeaa403..41e4e8070923 100644
--- a/kernel/watch_queue.c
+++ b/kernel/watch_queue.c
@@ -269,6 +269,15 @@ long watch_queue_set_size(struct pipe_inode_info *pipe, unsigned int nr_notes)
 	if (ret < 0)
 		goto error;
 
+	/*
+	 * pipe_resize_ring() does not update nr_accounted for watch_queue
+	 * pipes, because the above vastly overprovisions. Set nr_accounted on
+	 * and max_usage this pipe to the number that was actually charged to
+	 * the user above via account_pipe_buffers.
+	 */
+	pipe->max_usage = nr_pages;
+	pipe->nr_accounted = nr_pages;
+
 	ret = -ENOMEM;
 	pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
 	if (!pages)