[src/trunk]: src/sys/dev Pass residual back to b_resid for persistent snapshots.

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

details:   https://anonhg.NetBSD.org/src/rev/ee985304e56b
branches:  trunk
changeset: 828624:ee985304e56b
user:      hannken <hannken%NetBSD.org@localhost>
date:      Thu Dec 21 15:51:39 2017 +0000

description:
Pass residual back to b_resid for persistent snapshots.

diffstat:

 sys/dev/fss.c |  31 ++++++++++++++++++-------------
 1 files changed, 18 insertions(+), 13 deletions(-)

diffs (113 lines):

diff -r 90387df39aef -r ee985304e56b sys/dev/fss.c
--- a/sys/dev/fss.c     Thu Dec 21 15:51:07 2017 +0000
+++ b/sys/dev/fss.c     Thu Dec 21 15:51:39 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fss.c,v 1.102 2017/12/21 15:51:07 hannken Exp $        */
+/*     $NetBSD: fss.c,v 1.103 2017/12/21 15:51:39 hannken Exp $        */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.102 2017/12/21 15:51:07 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.103 2017/12/21 15:51:39 hannken Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -89,7 +89,7 @@
 static int fss_read_cluster(struct fss_softc *, u_int32_t);
 static void fss_bs_thread(void *);
 static int fss_bs_io(struct fss_softc *, fss_io_type,
-    u_int32_t, off_t, int, void *);
+    u_int32_t, off_t, int, void *, size_t *);
 static u_int32_t *fss_bs_indir(struct fss_softc *, u_int32_t);
 
 static kmutex_t fss_device_lock;       /* Protect all units. */
@@ -1009,7 +1009,7 @@
  */
 static int
 fss_bs_io(struct fss_softc *sc, fss_io_type rw,
-    u_int32_t cl, off_t off, int len, void *data)
+    u_int32_t cl, off_t off, int len, void *data, size_t *resid)
 {
        int error;
 
@@ -1020,7 +1020,7 @@
        error = vn_rdwr((rw == FSS_READ ? UIO_READ : UIO_WRITE), sc->sc_bs_vp,
            data, len, off, UIO_SYSSPACE,
            IO_ADV_ENCODE(POSIX_FADV_NOREUSE) | IO_NODELOCKED,
-           sc->sc_bs_lwp->l_cred, NULL, NULL);
+           sc->sc_bs_lwp->l_cred, resid, NULL);
        if (error == 0) {
                mutex_enter(sc->sc_bs_vp->v_interlock);
                error = VOP_PUTPAGES(sc->sc_bs_vp, trunc_page(off),
@@ -1049,7 +1049,7 @@
 
        if (sc->sc_indir_dirty) {
                if (fss_bs_io(sc, FSS_WRITE, sc->sc_indir_cur, 0,
-                   FSS_CLSIZE(sc), (void *)sc->sc_indir_data) != 0)
+                   FSS_CLSIZE(sc), (void *)sc->sc_indir_data, NULL) != 0)
                        return NULL;
                setbit(sc->sc_indir_valid, sc->sc_indir_cur);
        }
@@ -1059,7 +1059,7 @@
 
        if (isset(sc->sc_indir_valid, sc->sc_indir_cur)) {
                if (fss_bs_io(sc, FSS_READ, sc->sc_indir_cur, 0,
-                   FSS_CLSIZE(sc), (void *)sc->sc_indir_data) != 0)
+                   FSS_CLSIZE(sc), (void *)sc->sc_indir_data, NULL) != 0)
                        return NULL;
        } else
                memset(sc->sc_indir_data, 0, FSS_CLSIZE(sc));
@@ -1080,6 +1080,7 @@
        long off;
        char *addr;
        u_int32_t c, cl, ch, *indirp;
+       size_t resid;
        struct buf *bp, *nbp;
        struct fss_softc *sc;
        struct fss_cache *scp, *scl;
@@ -1116,14 +1117,18 @@
                                disk_busy(sc->sc_dkdev);
                                error = fss_bs_io(sc, FSS_READ, 0,
                                    dbtob(bp->b_blkno), bp->b_bcount,
-                                   bp->b_data);
+                                   bp->b_data, &resid);
+                               if (error)
+                                       resid = bp->b_bcount;
                                disk_unbusy(sc->sc_dkdev,
                                    (error ? 0 : bp->b_bcount), is_read);
-                       } else
+                       } else {
                                error = ENXIO;
+                               resid = bp->b_bcount;
+                       }
 
                        bp->b_error = error;
-                       bp->b_resid = (error ? bp->b_bcount : 0);
+                       bp->b_resid = resid;
                        biodone(bp);
 
                        mutex_enter(&sc->sc_slock);
@@ -1144,7 +1149,7 @@
                        indirp = fss_bs_indir(sc, scp->fc_cluster);
                        if (indirp != NULL) {
                                error = fss_bs_io(sc, FSS_WRITE, sc->sc_clnext,
-                                   0, FSS_CLSIZE(sc), scp->fc_data);
+                                   0, FSS_CLSIZE(sc), scp->fc_data, NULL);
                        } else
                                error = EIO;
 
@@ -1265,8 +1270,8 @@
                        /*
                         * Read from backing store.
                         */
-                       error =
-                           fss_bs_io(sc, FSS_READ, *indirp, off, len, addr);
+                       error = fss_bs_io(sc, FSS_READ,
+                           *indirp, off, len, addr, NULL);
 
                        mutex_enter(&sc->sc_slock);
                        if (error) {