Commit eff4f675 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'powerpc-6.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux 

Pull powerpc fix from Madhavan Srinivasan:

 - Add close() callback in vas_vm_ops struct for proper cleanup

Thanks to Haren Myneni.

* tag 'powerpc-6.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries/vas: Add close() callback in vas_vm_ops struct
parents 411a678d 05aa156e

arch/powerpc/platforms/book3s/vas-api.c

+36 −0
Original line number Diff line number Diff line
@@ -464,7 +464,43 @@ static vm_fault_t vas_mmap_fault(struct vm_fault *vmf) 
	return VM_FAULT_SIGBUS;

}



/*

 * During mmap() paste address, mapping VMA is saved in VAS window

 * struct which is used to unmap during migration if the window is

 * still open. But the user space can remove this mapping with

 * munmap() before closing the window and the VMA address will

 * be invalid. Set VAS window VMA to NULL in this function which

 * is called before VMA free.

 */

static void vas_mmap_close(struct vm_area_struct *vma)

{

	struct file *fp = vma->vm_file;

	struct coproc_instance *cp_inst = fp->private_data;

	struct vas_window *txwin;



	/* Should not happen */

	if (!cp_inst || !cp_inst->txwin) {

		pr_err("No attached VAS window for the paste address mmap\n");

		return;

	}



	txwin = cp_inst->txwin;

	/*

	 * task_ref.vma is set in coproc_mmap() during mmap paste

	 * address. So it has to be the same VMA that is getting freed.

	 */

	if (WARN_ON(txwin->task_ref.vma != vma)) {

		pr_err("Invalid paste address mmaping\n");

		return;

	}



	mutex_lock(&txwin->task_ref.mmap_mutex);

	txwin->task_ref.vma = NULL;

	mutex_unlock(&txwin->task_ref.mmap_mutex);

}



static const struct vm_operations_struct vas_vm_ops = {

	.close = vas_mmap_close,

	.fault = vas_mmap_fault,

};