vfio/type1: introduce a new member has_rsvd for struct vfio_dma

Introduce a new member has_rsvd for struct vfio_dma. This member is
used to indicate whether there are any reserved or invalid pfns in
the region represented by this vfio_dma. If it is true, it indicates
that there is at least one pfn in this region that is either reserved
or invalid.

Signed-off-by: Li Zhe <lizhe.67@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250814064714.56485-5-lizhe.67@bytedance.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Author: Li Zhe

drivers/vfio/vfio_iommu_type1.c

@@ -93,6 +93,7 @@ struct vfio_dma {
 	bool			iommu_mapped;
 	bool			lock_cap;	/* capable(CAP_IPC_LOCK) */
 	bool			vaddr_invalid;
+	bool			has_rsvd;	/* has 1 or more rsvd pfns */
 	struct task_struct	*task;
 	struct rb_root		pfn_list;	/* Ex-user pinned pfn list */
 	unsigned long		*bitmap;
@@ -782,6 +783,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr,
 	}
 
 out:
+	dma->has_rsvd |= rsvd;
 	ret = vfio_lock_acct(dma, lock_acct, false);
 
 unpin_out: