git: e413e15c1ad5 - main - swap_pager_freespace: fix freed count

The branch main has been updated by dougm:

URL: https://cgit.FreeBSD.org/src/commit/?id=e413e15c1ad5ba6dde8d2747c3c505cc39746c80

commit e413e15c1ad5ba6dde8d2747c3c505cc39746c80
Author:     Doug Moore <dougm@FreeBSD.org>
AuthorDate: 2024-08-07 08:37:18 +0000
Commit:     Doug Moore <dougm@FreeBSD.org>
CommitDate: 2024-08-07 08:37:18 +0000

    swap_pager_freespace: fix freed count
    
    Function swp_pager_meta_transfer uses 'pindex' as the start address of
    the swblk in calculating which page to lookup in order to count freed
    pages.  However, the lookup for a swblk at 'pindex' or greater may
    produce one greater than 'pindex', given by sb->p, and that's the
    value that should be used to compute a page adddress.
    
    Reviewed by:    kib
    Differential Revision:  https://reviews.freebsd.org/D46234
---
 sys/vm/swap_pager.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 9df1521858c1..59d947c71279 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -2201,10 +2201,9 @@ swp_pager_meta_transfer(vm_object_t srcobject, vm_object_t dstobject,
 				VM_OBJECT_WLOCK(srcobject);
 			}
 			if (moved != NULL) {
-				if (m != NULL && m->pindex != pindex + i - 1)
-					m = NULL;
-				m = m != NULL ? vm_page_next(m) :
-				    vm_page_lookup(srcobject, pindex + i);
+				m = (m != NULL && m->pindex == sb->p + i - 1) ?
+				    vm_page_next(m) :
+				    vm_page_lookup(srcobject, sb->p + i);
 				if (m == NULL || vm_page_none_valid(m))
 					mc++;
 			}