 @@ -1,14 +1,14 @@
-/*	$NetBSD: fss.c,v 1.81.4.4 2016/08/27 14:47:47 bouyer Exp $	*/
+/*	$NetBSD: fss.c,v 1.81.4.5 2018/03/13 16:38:28 snj Exp $	*/
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Juergen Hannken-Illjes.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
 @@ -26,27 +26,27 @@
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */
 /*
  * File system snapshot disk driver.
+ *
  * Block/character interface to the snapshot of a mounted file system.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.81.4.4 2016/08/27 14:47:47 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.81.4.5 2018/03/13 16:38:28 snj Exp $");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/namei.h>
 #include <sys/proc.h>
 #include <sys/errno.h>
 #include <sys/malloc.h>
 #include <sys/buf.h>
 #include <sys/ioctl.h>
 #include <sys/disklabel.h>
 #include <sys/device.h>
 #include <sys/disk.h>
 #include <sys/stat.h>
 @@ -80,27 +80,27 @@ dev_type_size(fss_size);
 static void fss_unmount_hook(struct mount *);
 static int fss_copy_on_write(void *, struct buf *, bool);
 static inline void fss_error(struct fss_softc *, const char *);
 static int fss_create_files(struct fss_softc *, struct fss_set *,
     off_t *, struct lwp *);
 static int fss_create_snapshot(struct fss_softc *, struct fss_set *,
     struct lwp *);
 static int fss_delete_snapshot(struct fss_softc *, struct lwp *);
 static int fss_softc_alloc(struct fss_softc *);
 static void fss_softc_free(struct fss_softc *);
 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. */
 static int fss_num_attached = 0;	/* Number of attached devices. */
 static struct vfs_hooks fss_vfs_hooks = {
 	.vh_unmount = fss_unmount_hook
 };
 const struct bdevsw fss_bdevsw = {
 	fss_open, fss_close, fss_strategy, fss_ioctl,
 	fss_dump, fss_size, D_DISK | D_MPSAFE
 };
 @@ -256,40 +256,46 @@ restart:
 	return error;
+}
 void
 fss_strategy(struct buf *bp)
+{
 	const bool write = ((bp->b_flags & B_READ) != B_READ);
 	struct fss_softc *sc = device_lookup_private(&fss_cd, minor(bp->b_dev));
 	mutex_enter(&sc->sc_slock);
 	if (write || !FSS_ISVALID(sc)) {
 		mutex_exit(&sc->sc_slock);
 		bp->b_error = (write ? EROFS : ENXIO);
-		bp->b_resid = bp->b_bcount;
+		goto done;
 		biodone(bp);
 		return;
+	}
 	/* Check bounds for non-persistent snapshots. */
 	if ((sc->sc_flags & FSS_PERSISTENT) == 0 &&
 	    bounds_check_with_mediasize(bp, DEV_BSIZE,
 	    btodb(FSS_CLTOB(sc, sc->sc_clcount - 1) + sc->sc_clresid)) <= 0)
 		goto done;
 	bp->b_rawblkno = bp->b_blkno;
 	bufq_put(sc->sc_bufq, bp);
 	cv_signal(&sc->sc_work_cv);
 	mutex_exit(&sc->sc_slock);
 	return;
 done:
 	mutex_exit(&sc->sc_slock);
 	bp->b_resid = bp->b_bcount;
 	biodone(bp);
+}
 int
 fss_read(dev_t dev, struct uio *uio, int flags)
+{
 	return physio(fss_strategy, NULL, dev, B_READ, minphys, uio);
+}
 int
 fss_write(dev_t dev, struct uio *uio, int flags)
+{
 	return physio(fss_strategy, NULL, dev, B_WRITE, minphys, uio);
+}
 @@ -983,59 +989,61 @@ restart:
 			bp = mbp;
 		else {
 			bp = getiobuf(NULL, true);
 			nestiobuf_setup(mbp, bp, offset, len);
+		}
 		bp->b_lblkno = 0;
 		bp->b_blkno = dblk;
 		bdev_strategy(bp);
 		dblk += btodb(len);
 		offset += len;
 		todo -= len;
+	}
 	error = biowait(mbp);
 	if (error == 0 && mbp->b_resid != 0)
 		error = EIO;
 	putiobuf(mbp);
 	mutex_enter(&sc->sc_slock);
 	scp->fc_type = (error ? FSS_CACHE_FREE : FSS_CACHE_VALID);
 	cv_broadcast(&scp->fc_state_cv);
 	if (error == 0) {
 		setbit(sc->sc_copied, scp->fc_cluster);
 		cv_signal(&sc->sc_work_cv);
+	}
 	mutex_exit(&sc->sc_slock);
 	return error;
+}
 /*
  * Read/write clusters from/to backing store.
  * For persistent snapshots must be called with cl == 0. off is the
  * offset into the snapshot.
  */
 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;
 	off += FSS_CLTOB(sc, cl);
 	vn_lock(sc->sc_bs_vp, LK_EXCLUSIVE|LK_RETRY);
 	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),
 		    round_page(off+len), PGO_CLEANIT | PGO_FREE | PGO_SYNCIO);
+	}
 	VOP_UNLOCK(sc->sc_bs_vp);
 	return error;
+}
 /*
  * Get a pointer to the indirect slot for this cluster.
 @@ -1044,57 +1052,58 @@ static u_int32_t *
 fss_bs_indir(struct fss_softc *sc, u_int32_t cl)
+{
 	u_int32_t icl;
 	int ioff;
 	icl = cl/(FSS_CLSIZE(sc)/sizeof(u_int32_t));
 	ioff = cl%(FSS_CLSIZE(sc)/sizeof(u_int32_t));
 	if (sc->sc_indir_cur == icl)
 		return &sc->sc_indir_data[ioff];
 	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);
+	}
 	sc->sc_indir_dirty = 0;
 	sc->sc_indir_cur = icl;
 	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));
 	return &sc->sc_indir_data[ioff];
+}
 /*
  * The kernel thread (one for every active snapshot).
+ *
  * After wakeup it cleans the cache and runs the I/O requests.
  */
 static void
 fss_bs_thread(void *arg)
+{
 	bool thread_idle, is_valid;
 	int error, i, todo, len, crotor, is_read;
 	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;
 	sc = arg;
 	scl = sc->sc_cache+sc->sc_cache_size;
 	crotor = 0;
 	thread_idle = false;
 	mutex_enter(&sc->sc_slock);
 	for (;;) {
 		if (thread_idle)
 @@ -1111,55 +1120,59 @@ fss_bs_thread(void *arg)
 		if (sc->sc_flags & FSS_PERSISTENT) {
 			if ((bp = bufq_get(sc->sc_bufq)) == NULL)
 				continue;
 			is_valid = FSS_ISVALID(sc);
 			is_read = (bp->b_flags & B_READ);
 			thread_idle = false;
 			mutex_exit(&sc->sc_slock);
 			if (is_valid) {
 				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);
 			continue;
+		}
 		/*
 		 * Clean the cache
 		 */
 		for (i = 0; i < sc->sc_cache_size; i++) {
 			crotor = (crotor + 1) % sc->sc_cache_size;
 			scp = sc->sc_cache + crotor;
 			if (scp->fc_type != FSS_CACHE_VALID)
 				continue;
 			mutex_exit(&sc->sc_slock);
 			thread_idle = false;
 			indirp = fss_bs_indir(sc, scp->fc_cluster);
 			if (indirp != NULL) {
 				error = fss_bs_io(sc, FSS_WRITE, sc->sc_clnext,
-, FSS_CLSIZE(sc), scp->fc_data);
+, FSS_CLSIZE(sc), scp->fc_data, NULL);
 			} else
 				error = EIO;
 			mutex_enter(&sc->sc_slock);
 			if (error == 0) {
 				*indirp = sc->sc_clnext++;
 				sc->sc_indir_dirty = 1;
 			} else
 				fss_error(sc, "write error on backing store");
 			scp->fc_type = FSS_CACHE_FREE;
 			cv_signal(&sc->sc_cache_cv);
 			break;
 @@ -1207,26 +1220,28 @@ fss_bs_thread(void *arg)
 			nbp = getiobuf(NULL, true);
 			nbp->b_flags = B_READ;
 			nbp->b_resid = nbp->b_bcount = bp->b_bcount;
 			nbp->b_bufsize = bp->b_bcount;
 			nbp->b_data = bp->b_data;
 			nbp->b_blkno = bp->b_blkno;
 			nbp->b_lblkno = 0;
 			nbp->b_dev = sc->sc_bdev;
 			SET(nbp->b_cflags, BC_BUSY);	/* mark buffer busy */
 			bdev_strategy(nbp);
 			error = biowait(nbp);
 			if (error == 0 && nbp->b_resid != 0)
 				error = EIO;
 			if (error != 0) {
 				bp->b_resid = bp->b_bcount;
 				bp->b_error = nbp->b_error;
 				disk_unbusy(sc->sc_dkdev, 0, is_read);
 				biodone(bp);
+			}
 			putiobuf(nbp);
 			mutex_enter(&sc->sc_slock);
 			break;
+		}
 		if (error)
 			continue;
 @@ -1258,28 +1273,28 @@ fss_bs_thread(void *arg)
 					    scp->fc_cluster == c)
 						break;
 				if (scp < scl)
 					memcpy(addr, (char *)scp->fc_data+off,
 					    len);
 				else
 					memset(addr, 0, len);
 				continue;
+			}
 			/*
 			 * Read from backing store.
 			 */
-			error =
+			error = fss_bs_io(sc, FSS_READ,
-			    fss_bs_io(sc, FSS_READ, *indirp, off, len, addr);
+			    *indirp, off, len, addr, NULL);
 			mutex_enter(&sc->sc_slock);
 			if (error) {
 				bp->b_resid = bp->b_bcount;
 				bp->b_error = error;
 				break;
+			}
+		}
 		mutex_exit(&sc->sc_slock);
 		disk_unbusy(sc->sc_dkdev, (error ? 0 : bp->b_bcount), is_read);
 		biodone(bp);