Module Name: src
Committed By: yamt
Date: Tue Jan 24 02:09:35 UTC 2012
Modified Files:
src/sys/miscfs/genfs [yamt-pagecache]: genfs_io.c
Log Message:
- g/c #if 0'ed code
- minor optimization
- comments
To generate a diff of this commit:
cvs rdiff -u -r1.53.2.8 -r1.53.2.9 src/sys/miscfs/genfs/genfs_io.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/miscfs/genfs/genfs_io.c
diff -u src/sys/miscfs/genfs/genfs_io.c:1.53.2.8 src/sys/miscfs/genfs/genfs_io.c:1.53.2.9
--- src/sys/miscfs/genfs/genfs_io.c:1.53.2.8 Wed Jan 18 02:09:05 2012
+++ src/sys/miscfs/genfs/genfs_io.c Tue Jan 24 02:09:34 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: genfs_io.c,v 1.53.2.8 2012/01/18 02:09:05 yamt Exp $ */
+/* $NetBSD: genfs_io.c,v 1.53.2.9 2012/01/24 02:09:34 yamt Exp $ */
/*
* Copyright (c) 1982, 1986, 1989, 1993
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.53.2.8 2012/01/18 02:09:05 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: genfs_io.c,v 1.53.2.9 2012/01/24 02:09:34 yamt Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -224,6 +224,10 @@ startover:
error = EBUSY;
goto out_err;
}
+ /*
+ * lock and unlock g_glock to ensure that no one is truncating
+ * the file behind us.
+ */
if (!genfs_node_rdtrylock(vp)) {
genfs_rel_pages(ap->a_m, npages);
@@ -590,19 +594,13 @@ startover:
iobytes);
skipbytes += iobytes;
- mutex_enter(uobj->vmobjlock);
- for (i = 0; i < holepages; i++) {
-#if 0
- if (memwrite) {
- uvm_pagemarkdirty(pgs[pidx + i],
- UVM_PAGE_STATUS_DIRTY);
- }
-#endif
- if (!blockalloc) {
+ if (!blockalloc) {
+ mutex_enter(uobj->vmobjlock);
+ for (i = 0; i < holepages; i++) {
pgs[pidx + i]->flags |= PG_HOLE;
}
+ mutex_exit(uobj->vmobjlock);
}
- mutex_exit(uobj->vmobjlock);
continue;
}
@@ -887,7 +885,6 @@ genfs_do_putpages(struct vnode *vp, off_
(origflags & PGO_JOURNALLOCKED) == 0);
retry:
- written = false;
flags = origflags;
KASSERT((vp->v_iflag & VI_ONWORKLST) != 0 ||
(vp->v_iflag & VI_WRMAPDIRTY) == 0);
@@ -939,10 +936,6 @@ retry:
error = 0;
wasclean = (vp->v_numoutput == 0);
- nextoff = startoff;
- if (endoff == 0 || flags & PGO_ALLPAGES) {
- endoff = trunc_page(LLONG_MAX);
- }
/*
* if this vnode is known not to have dirty pages,
@@ -959,9 +952,14 @@ retry:
}
/*
- * start the loop.
+ * start the loop to scan pages.
*/
+ written = false;
+ nextoff = startoff;
+ if (endoff == 0 || flags & PGO_ALLPAGES) {
+ endoff = trunc_page(LLONG_MAX);
+ }
freeflag = pagedaemon ? PG_PAGEOUT : PG_RELEASED;
tryclean = true;
uvm_page_array_init(&a);
@@ -1102,7 +1100,14 @@ retry:
/*
* XXX PG_PAGER1 incompatibility check.
- * this is a kludge for nfs.
+ *
+ * this is a kludge for nfs. nfs has two kind of dirty
+ * pages:
+ * - not written to the server yet
+ * - written to the server but not committed yet
+ * the latter is marked as PG_NEEDCOMMIT. (== PG_PAGER1)
+ * nfs doesn't want them being clustered together.
+ *
* probably it's better to make PG_NEEDCOMMIT a first
* level citizen for uvm/genfs.
*/
