[src/uebayasi-xip]: src/sys/miscfs/genfs Put back XIP putpages, but slightly ...

[uebayasi <uebayasi%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/723fb233274b
branches:  uebayasi-xip
changeset: 751901:723fb233274b
user:      uebayasi <uebayasi%NetBSD.org@localhost>
date:      Sun Nov 21 17:07:38 2010 +0000

description:
Put back XIP putpages, but slightly modifed to be called from the
generic putpages, and to call pgo_get() than a specific function.
Without this, UVM went mad after unmount (vinval, etc.).

diffstat:

 sys/miscfs/genfs/genfs_io.c |  96 ++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 94 insertions(+), 2 deletions(-)

diffs (131 lines):

diff -r 7955dd0f2242 -r 723fb233274b sys/miscfs/genfs/genfs_io.c
--- a/sys/miscfs/genfs/genfs_io.c       Sun Nov 21 15:27:36 2010 +0000
+++ b/sys/miscfs/genfs/genfs_io.c       Sun Nov 21 17:07:38 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: genfs_io.c,v 1.36.2.62 2010/11/21 15:00:12 uebayasi Exp $      */
+/*     $NetBSD: genfs_io.c,v 1.36.2.63 2010/11/21 17:07:38 uebayasi Exp $      */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.36.2.62 2010/11/21 15:00:12 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.36.2.63 2010/11/21 17:07:38 uebayasi Exp $");
 
 #include "opt_xip.h"
 
@@ -993,6 +993,12 @@
  *     range by an estimate of the relatively higher cost of the hash lookup.
  */
 
+#ifdef XIP
+static int
+genfs_do_putpages_xip_free(struct vnode *vp, off_t startoff, off_t endoff,
+    int origflags);
+#endif
+
 int
 genfs_putpages(void *v)
 {
@@ -1062,6 +1068,15 @@
                                WAPBL_END(vp->v_mount);
                        fstrans_done(vp->v_mount);
                }
+#ifdef XIP
+               if ((vp->v_vflag & VV_XIP) != 0) {
+                       if (flags & PGO_FREE) {
+                               error = genfs_do_putpages_xip_free(vp,
+                                   startoff, endoff, origflags);
+                               KASSERT(error == 0);
+                       }
+               }
+#endif
                mutex_exit(slock);
                return (0);
        }
@@ -1469,6 +1484,83 @@
        return (error);
 }
 
+#ifdef XIP
+static int
+genfs_do_putpages_xip_free(struct vnode *vp, off_t startoff, off_t endoff,
+    int origflags)
+{
+       struct uvm_object * const uobj = &vp->v_uobj;
+ 
+       KASSERT(uobj->uo_npages == 0);
+
+       /*
+        * For PGO_FREE (or (PGO_CLEANIT | PGO_FREE)), we invalidate MMU
+        * mappings of both XIP pages and XIP zero pages.
+        *
+        * Hole page is freed when one of its mapped offset is freed, even if
+        * one file (vnode) has many holes and mapping its zero page to all
+        * of those hole pages.
+        *
+        * We don't know which pages are currently mapped in the given vnode,
+        * because XIP pages are not added to vnode.  What we can do is to
+        * locate pages by querying the filesystem as done in getpages.  Call
+        * genfs_do_getpages_xip_io().
+        */
+ 
+       off_t off, eof;
+ 
+       off = trunc_page(startoff);
+       if (endoff == 0 || (origflags & PGO_ALLPAGES))
+               GOP_SIZE(vp, vp->v_size, &eof, GOP_SIZE_MEM);
+       else
+               eof = endoff;
+ 
+       while (off < eof) {
+               int npages, orignpages, error, i;
+               struct vm_page *pgs[maxpages], *pg;
+ 
+               npages = round_page(eof - off) >> PAGE_SHIFT;
+               if (npages > maxpages)
+                       npages = maxpages;
+ 
+               orignpages = npages;
+               KASSERT(mutex_owned(&uobj->vmobjlock));
+               error = (*uobj->pgops->pgo_get)(uobj, off, pgs, &npages, 0,
+                   VM_PROT_ALL, 0, PGO_SYNCIO);
+               KASSERT(error == 0);
+               KASSERT(npages == orignpages);
+               mutex_enter(&uobj->vmobjlock);
+               for (i = 0; i < npages; i++) {
+                       pg = pgs[i];
+                       if (pg == NULL || pg == PGO_DONTCARE)
+                               continue;
+                       if (pg == PGO_HOLE) {
+                               pg = uvm_page_holepage;
+                               KASSERT(pg != NULL);
+                               /*
+                                * XXXUEBS
+                                * Invalidating hole pages may be unnecessary,
+                                * but just for safety.
+                                */
+                       } else {
+                               /*
+                                * Freeing normal XIP pages; nothing to do.
+                                */
+                               KASSERT((pg->flags & PG_RDONLY) != 0);
+                               KASSERT((pg->flags & PG_CLEAN) != 0);
+                               KASSERT((pg->flags & PG_FAKE) == 0);
+                               KASSERT((pg->flags & PG_DEVICE) != 0);
+                               pg->flags &= ~PG_BUSY;
+                       }
+                       pmap_page_protect(pg, VM_PROT_NONE);
+               }
+               off += npages << PAGE_SHIFT;
+       }
+
+       return 0;
+}
+#endif
+
 int
 genfs_gop_write(struct vnode *vp, struct vm_page **pgs, int npages, int flags)
 {