Merge tag 'driver-core-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core updates for 6.7-rc1. Nothing major in
  here at all, just a small number of changes including:

   - minor cleanups and updates from Andy Shevchenko

   - __counted_by addition

   - firmware_loader update for aborting loads cleaner

   - other minor changes, details in the shortlog

   - documentation update

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (21 commits)
  firmware_loader: Abort all upcoming firmware load request once reboot triggered
  firmware_loader: Refactor kill_pending_fw_fallback_reqs()
  Documentation: security-bugs.rst: linux-distros relaxed their rules
  driver core: Release all resources during unbind before updating device links
  driver core: class: remove boilerplate code
  driver core: platform: Annotate struct irq_affinity_devres with __counted_by
  resource: Constify resource crosscheck APIs
  resource: Unify next_resource() and next_resource_skip_children()
  resource: Reuse for_each_resource() macro
  PCI: Implement custom llseek for sysfs resource entries
  kernfs: sysfs: support custom llseek method for sysfs entries
  debugfs: Fix __rcu type comparison warning
  device property: Replace custom implementation of COUNT_ARGS()
  drivers: base: test: Make property entry API test modular
  driver core: Add missing parameter description to __fwnode_link_add()
  device property: Clarify usage scope of some struct fwnode_handle members
  devres: rename the first parameter of devm_add_action(_or_reset)
  driver core: platform: Unify the firmware node type check
  driver core: platform: Use temporary variable in platform_device_add()
  driver core: platform: Refactor error path in a couple places
  ...

1 files changed, 28 insertions, 1 deletions

diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index aaa76410e550..f0cb729e9a97 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -854,6 +854,33 @@ static __poll_t kernfs_fop_poll(struct file *filp, poll_table *wait)
 	return ret;
 }
 
+static loff_t kernfs_fop_llseek(struct file *file, loff_t offset, int whence)
+{
+	struct kernfs_open_file *of = kernfs_of(file);
+	const struct kernfs_ops *ops;
+	loff_t ret;
+
+	/*
+	 * @of->mutex nests outside active ref and is primarily to ensure that
+	 * the ops aren't called concurrently for the same open file.
+	 */
+	mutex_lock(&of->mutex);
+	if (!kernfs_get_active(of->kn)) {
+		mutex_unlock(&of->mutex);
+		return -ENODEV;
+	}
+
+	ops = kernfs_ops(of->kn);
+	if (ops->llseek)
+		ret = ops->llseek(of, offset, whence);
+	else
+		ret = generic_file_llseek(file, offset, whence);
+
+	kernfs_put_active(of->kn);
+	mutex_unlock(&of->mutex);
+	return ret;
+}
+
 static void kernfs_notify_workfn(struct work_struct *work)
 {
 	struct kernfs_node *kn;
@@ -956,7 +983,7 @@ EXPORT_SYMBOL_GPL(kernfs_notify);
 const struct file_operations kernfs_file_fops = {
 	.read_iter	= kernfs_fop_read_iter,
 	.write_iter	= kernfs_fop_write_iter,
-	.llseek		= generic_file_llseek,
+	.llseek		= kernfs_fop_llseek,
 	.mmap		= kernfs_fop_mmap,
 	.open		= kernfs_fop_open,
 	.release	= kernfs_fop_release,