[PATCH 13/14] ptp: vmclock: convert mmap hook to mmap_prepare

[Lorenzo Stoakes (ARM)]

Move from the deprecated mmap hook to the new mmap_prepare hook, using the
I/O PFN remap mmap action to map the clock page and retaining the -EAGAIN
error on failure via the action error override.

Signed-off-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>
---
 drivers/ptp/ptp_vmclock.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/ptp/ptp_vmclock.c b/drivers/ptp/ptp_vmclock.c
index bb0e14bac9f2..e44433430044 100644
--- a/drivers/ptp/ptp_vmclock.c
+++ b/drivers/ptp/ptp_vmclock.c
@@ -364,27 +364,26 @@ struct vmclock_file_state {
 	atomic_t seq;
 };
 
-static int vmclock_miscdev_mmap(struct file *fp, struct vm_area_struct *vma)
+static int vmclock_miscdev_mmap_prepare(struct vm_area_desc *desc)
 {
-	struct vmclock_file_state *fst = fp->private_data;
+	struct vmclock_file_state *fst = desc->file->private_data;
 	struct vmclock_state *st = fst->st;
 
-	if ((vma->vm_flags & (VM_READ|VM_WRITE)) != VM_READ)
+	if (!vma_desc_test(desc, VMA_READ_BIT) ||
+	    vma_desc_test(desc, VMA_WRITE_BIT))
 		return -EROFS;
 
 	/*
 	 * Restrict the read-only mapping so it cannot be upgraded to
 	 * writable later with mprotect().
 	 */
-	vm_flags_clear(vma, VM_MAYWRITE);
+	vma_desc_clear_flags(desc, VMA_MAYWRITE_BIT);
 
-	if (vma->vm_end - vma->vm_start != PAGE_SIZE || vma->vm_pgoff)
+	if (vma_desc_size(desc) != PAGE_SIZE || desc->pgoff)
 		return -EINVAL;
 
-	if (io_remap_pfn_range(vma, vma->vm_start,
-			       st->res.start >> PAGE_SHIFT, PAGE_SIZE,
-			       vma->vm_page_prot))
-		return -EAGAIN;
+	mmap_action_ioremap_full(desc, st->res.start >> PAGE_SHIFT);
+	desc->action.error_override = -EAGAIN;
 
 	return 0;
 }
@@ -484,7 +483,7 @@ static const struct file_operations vmclock_miscdev_fops = {
 	.owner = THIS_MODULE,
 	.open = vmclock_miscdev_open,
 	.release = vmclock_miscdev_release,
-	.mmap = vmclock_miscdev_mmap,
+	.mmap_prepare = vmclock_miscdev_mmap_prepare,
 	.read = vmclock_miscdev_read,
 	.poll = vmclock_miscdev_poll,
 };

-- 
2.56.0