git: 1390a5cbeb18 - main - Add pgo_freespace method

[Konstantin Belousov]

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=1390a5cbeb1828b11584783c53f50b9679379651

commit 1390a5cbeb1828b11584783c53f50b9679379651
Author:     Konstantin Belousov <kib at FreeBSD.org>
AuthorDate: 2021-05-01 17:12:32 +0000
Commit:     Konstantin Belousov <kib at FreeBSD.org>
CommitDate: 2021-05-07 14:08:03 +0000

    Add pgo_freespace method
    
    Makes the code in vm_object collapse/page_remove cleaner
    
    Reviewed by:    markj
    Tested by:      pho
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D30070
---
 sys/vm/swap_pager.c |  7 ++++---
 sys/vm/swap_pager.h |  1 -
 sys/vm/vm_object.c  | 24 ++++++++----------------
 sys/vm/vm_pager.h   | 14 ++++++++++++++
 4 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 294f61e22cb1..f09a6ffc80dc 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -437,6 +437,8 @@ static void	swap_pager_set_writeable_dirty(vm_object_t object);
 static bool	swap_pager_mightbedirty(vm_object_t object);
 static void	swap_pager_getvp(vm_object_t object, struct vnode **vpp,
     bool *vp_heldp);
+static void	swap_pager_freespace(vm_object_t object, vm_pindex_t start,
+    vm_size_t size);
 
 struct pagerops swappagerops = {
 	.pgo_init =	swap_pager_init,	/* early system initialization of pager	*/
@@ -452,6 +454,7 @@ struct pagerops swappagerops = {
 	.pgo_set_writeable_dirty = swap_pager_set_writeable_dirty,
 	.pgo_mightbedirty = swap_pager_mightbedirty,
 	.pgo_getvp = swap_pager_getvp,
+	.pgo_freespace = swap_pager_freespace,
 };
 
 /*
@@ -942,8 +945,6 @@ sysctl_swap_fragmentation(SYSCTL_HANDLER_ARGS)
  * SWAP_PAGER_FREESPACE() -	frees swap blocks associated with a page
  *				range within an object.
  *
- *	This is a globally accessible routine.
- *
  *	This routine removes swapblk assignments from swap metadata.
  *
  *	The external callers of this routine typically have already destroyed
@@ -952,7 +953,7 @@ sysctl_swap_fragmentation(SYSCTL_HANDLER_ARGS)
  *
  *	The object must be locked.
  */
-void
+static void
 swap_pager_freespace(vm_object_t object, vm_pindex_t start, vm_size_t size)
 {
 
diff --git a/sys/vm/swap_pager.h b/sys/vm/swap_pager.h
index 59ca2cc2cfdb..7a2ea12e887d 100644
--- a/sys/vm/swap_pager.h
+++ b/sys/vm/swap_pager.h
@@ -76,7 +76,6 @@ struct xswdev;
 int swap_dev_info(int name, struct xswdev *xs, char *devname, size_t len);
 void swap_pager_copy(vm_object_t, vm_object_t, vm_pindex_t, int);
 vm_pindex_t swap_pager_find_least(vm_object_t object, vm_pindex_t pindex);
-void swap_pager_freespace(vm_object_t, vm_pindex_t, vm_size_t);
 void swap_pager_swap_init(void);
 int swap_pager_nswapdev(void);
 int swap_pager_reserve(vm_object_t, vm_pindex_t, vm_size_t);
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index b601bff33ff4..7b380608cdf4 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -1277,8 +1277,8 @@ vm_object_madvise_freespace(vm_object_t object, int advice, vm_pindex_t pindex,
     vm_size_t size)
 {
 
-	if (advice == MADV_FREE && object->type == OBJT_SWAP)
-		swap_pager_freespace(object, pindex, size);
+	if (advice == MADV_FREE)
+		vm_pager_freespace(object, pindex, size);
 }
 
 /*
@@ -1798,9 +1798,7 @@ vm_object_collapse_scan(vm_object_t object)
 
 		if (p->pindex < backing_offset_index ||
 		    new_pindex >= object->size) {
-			if (backing_object->type == OBJT_SWAP)
-				swap_pager_freespace(backing_object, p->pindex,
-				    1);
+			vm_pager_freespace(backing_object, p->pindex, 1);
 
 			KASSERT(!pmap_page_is_mapped(p),
 			    ("freeing mapped page %p", p));
@@ -1849,9 +1847,7 @@ vm_object_collapse_scan(vm_object_t object)
 			 * page alone.  Destroy the original page from the
 			 * backing object.
 			 */
-			if (backing_object->type == OBJT_SWAP)
-				swap_pager_freespace(backing_object, p->pindex,
-				    1);
+			vm_pager_freespace(backing_object, p->pindex, 1);
 			KASSERT(!pmap_page_is_mapped(p),
 			    ("freeing mapped page %p", p));
 			if (vm_page_remove(p))
@@ -1875,9 +1871,8 @@ vm_object_collapse_scan(vm_object_t object)
 		}
 
 		/* Use the old pindex to free the right page. */
-		if (backing_object->type == OBJT_SWAP)
-			swap_pager_freespace(backing_object,
-			    new_pindex + backing_offset_index, 1);
+		vm_pager_freespace(backing_object, new_pindex +
+		    backing_offset_index, 1);
 
 #if VM_NRESERVLEVEL > 0
 		/*
@@ -2138,11 +2133,8 @@ wired:
 	}
 	vm_object_pip_wakeup(object);
 
-	if (object->type == OBJT_SWAP) {
-		if (end == 0)
-			end = object->size;
-		swap_pager_freespace(object, start, end - start);
-	}
+	vm_pager_freespace(object, start, (end == 0 ? object->size : end) -
+	    start);
 }
 
 /*
diff --git a/sys/vm/vm_pager.h b/sys/vm/vm_pager.h
index cb2a896c8749..6a35c066bea6 100644
--- a/sys/vm/vm_pager.h
+++ b/sys/vm/vm_pager.h
@@ -67,6 +67,8 @@ typedef void pgo_set_writeable_dirty_t(vm_object_t);
 typedef bool pgo_mightbedirty_t(vm_object_t);
 typedef void pgo_getvp_t(vm_object_t object, struct vnode **vpp,
     bool *vp_heldp);
+typedef void pgo_freespace_t(vm_object_t object, vm_pindex_t start,
+    vm_size_t size);
 
 struct pagerops {
 	pgo_init_t		*pgo_init;		/* Initialize pager. */
@@ -83,6 +85,7 @@ struct pagerops {
 	pgo_set_writeable_dirty_t *pgo_set_writeable_dirty;
 	pgo_mightbedirty_t	*pgo_mightbedirty;
 	pgo_getvp_t		*pgo_getvp;
+	pgo_freespace_t		*pgo_freespace;
 };
 
 extern struct pagerops defaultpagerops;
@@ -236,6 +239,17 @@ vm_pager_getvp(vm_object_t object, struct vnode **vpp, bool *vp_heldp)
 	}
 }
 
+static __inline void
+vm_pager_freespace(vm_object_t object, vm_pindex_t start,
+    vm_size_t size)
+{
+	pgo_freespace_t *method;
+
+	method = pagertab[object->type]->pgo_freespace;
+	if (method != NULL)
+		method(object, start, size);
+}
+
 struct cdev_pager_ops {
 	int (*cdev_pg_fault)(vm_object_t vm_obj, vm_ooffset_t offset,
 	    int prot, vm_page_t *mres);