[src/uebayasi-xip]: src/sys Factor out the part which lookups physical page "...

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

details:   https://anonhg.NetBSD.org/src/rev/546ec9b02f4f
branches:  uebayasi-xip
changeset: 751860:546ec9b02f4f
user:      uebayasi <uebayasi%NetBSD.org@localhost>
date:      Tue Nov 16 07:44:24 2010 +0000

description:
Factor out the part which lookups physical page "identity" from
UVM object, into sys/uvm/uvm_vnode.c:uvn_findpage_xip().  Eventually
this will become a call to cdev UVM object pager.

diffstat:

 sys/miscfs/genfs/genfs_io.c |  25 ++++++++-----------------
 sys/uvm/uvm_extern.h        |   3 ++-
 sys/uvm/uvm_vnode.c         |  40 ++++++++++++++++++++++++++++++++++++++--
 3 files changed, 48 insertions(+), 20 deletions(-)

diffs (129 lines):

diff -r 00996a328fc9 -r 546ec9b02f4f sys/miscfs/genfs/genfs_io.c
--- a/sys/miscfs/genfs/genfs_io.c       Tue Nov 16 03:03:28 2010 +0000
+++ b/sys/miscfs/genfs/genfs_io.c       Tue Nov 16 07:44:24 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: genfs_io.c,v 1.36.2.31 2010/11/15 17:32:01 uebayasi Exp $      */
+/*     $NetBSD: genfs_io.c,v 1.36.2.32 2010/11/16 07:44:25 uebayasi Exp $      */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.36.2.31 2010/11/15 17:32:01 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.36.2.32 2010/11/16 07:44:25 uebayasi Exp $");
 
 #include "opt_xip.h"
 
@@ -869,29 +869,20 @@
                 * XIP page metadata assignment
                 * - Unallocated block is redirected to the dedicated zero'ed
                 *   page.
-                * - Assume that struct vm_page *[] array of this segment is
-                *   allocated and linearly ordered by physical address.
                 */
                if (blkno < 0) {
                        zero_page = uvm_page_zeropage_alloc();
                        KASSERT(zero_page != NULL);
                        pps[i] = zero_page;
                } else {
-                       struct vm_physseg *seg;
-                       daddr_t seg_off;
-                       struct vm_page *pg;
+                       daddr_t blk_off, fs_off;
 
-                       seg = devvp->v_physseg;
-                       KASSERT(seg != NULL);
-                       /* bus_space_mmap cookie -> paddr_t */
-                       seg_off = (blkno << dev_bshift) +
-                           (off - (lbn << fs_bshift));
-                       KASSERT((seg_off & PAGE_MASK) == 0);
-                       pg = seg->pgs + (seg_off >> PAGE_SHIFT);
-                       KASSERT(pg->phys_addr ==
-                           (seg->start << PAGE_SHIFT) + seg_off);
+                       blk_off = blkno << dev_bshift;
+                       fs_off = off - (lbn << fs_bshift);
 
-                       pps[i] = pg;
+                       pps[i] = uvn_findpage_xip(&devvp->v_uobj,
+                           blk_off + fs_off);
+                       KASSERT(pps[i] != NULL);
                }
 
                UVMHIST_LOG(ubchist, "xip pgs %d => phys_addr=0x%lx (%p)",
diff -r 00996a328fc9 -r 546ec9b02f4f sys/uvm/uvm_extern.h
--- a/sys/uvm/uvm_extern.h      Tue Nov 16 03:03:28 2010 +0000
+++ b/sys/uvm/uvm_extern.h      Tue Nov 16 07:44:24 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_extern.h,v 1.161.2.11 2010/11/15 08:41:44 uebayasi Exp $   */
+/*     $NetBSD: uvm_extern.h,v 1.161.2.12 2010/11/16 07:44:24 uebayasi Exp $   */
 
 /*
  *
@@ -763,6 +763,7 @@
 bool                   uvn_text_p(struct uvm_object *);
 bool                   uvn_clean_p(struct uvm_object *);
 bool                   uvn_needs_writefault_p(struct uvm_object *);
+struct vm_page         *uvn_findpage_xip(struct uvm_object *, off_t);
 
 /* kern_malloc.c */
 void                   kmeminit_nkmempages(void);
diff -r 00996a328fc9 -r 546ec9b02f4f sys/uvm/uvm_vnode.c
--- a/sys/uvm/uvm_vnode.c       Tue Nov 16 03:03:28 2010 +0000
+++ b/sys/uvm/uvm_vnode.c       Tue Nov 16 07:44:24 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_vnode.c,v 1.93.2.2 2010/08/25 14:21:23 uebayasi Exp $      */
+/*     $NetBSD: uvm_vnode.c,v 1.93.2.3 2010/11/16 07:44:25 uebayasi Exp $      */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -50,7 +50,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_vnode.c,v 1.93.2.2 2010/08/25 14:21:23 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_vnode.c,v 1.93.2.3 2010/11/16 07:44:25 uebayasi Exp $");
 
 #include "opt_uvmhist.h"
 #include "opt_xip.h"
@@ -404,3 +404,39 @@
        return uvn_clean_p(uobj) ||
            (vp->v_iflag & (VI_WRMAP|VI_WRMAPDIRTY)) == VI_WRMAP;
 }
+
+/*
+ * uvn_findpage_xip
+ *     Lookup a physical page identity (== struct vm_page * in
+ *     the current UVM design) within the given vnode, at the
+ *     given offset.
+ */
+struct vm_page *
+uvn_findpage_xip(struct uvm_object *uobj, off_t off)
+{
+       struct vnode *vp = (struct vnode *)uobj;
+       struct vm_physseg *seg;
+       struct vm_page *pg;
+
+       KASSERT((vp->v_vflag & VV_XIP) != 0);
+       KASSERT((off & PAGE_MASK) == 0);
+
+       /*
+        * Lookup a physical page identity from the underlying physical
+        * segment.
+        *
+        * Eventually, this will be replaced by a call of character
+        * device pager method, which is a generalized version of
+        * cdev_mmap().  Which means that v_physseg will become struct
+        * uvm_object *, and this will call cdev_page(uobj, off).
+        */
+
+       seg = vp->v_physseg;
+       KASSERT(seg != NULL);
+
+       pg = seg->pgs + (off >> PAGE_SHIFT);
+
+       KASSERT(pg->phys_addr == (seg->start << PAGE_SHIFT) + off);
+
+       return pg;
+}