--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/usr/src/uts/common/fs/zfs/vdev_disk.c	Mon Oct 31 11:33:35 2005 -0800
@@ -0,0 +1,307 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/zfs_context.h>
+#include <sys/spa.h>
+#include <sys/vdev_disk.h>
+#include <sys/vdev_impl.h>
+#include <sys/fs/zfs.h>
+#include <sys/zio.h>
+#include <sys/sunddi.h>
+
+/*
+ * Virtual device vector for disks.
+ */
+
+extern ldi_ident_t zfs_li;
+
+typedef struct vdev_disk_buf {
+	buf_t	vdb_buf;
+	zio_t	*vdb_io;
+} vdev_disk_buf_t;
+
+static int
+vdev_disk_open(vdev_t *vd, uint64_t *psize, uint64_t *ashift)
+{
+	vdev_disk_t *dvd;
+	int error;
+
+	/*
+	 * We must have a pathname, and it must be absolute.
+	 */
+	if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
+		vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
+		return (EINVAL);
+	}
+
+	dvd = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP);
+
+	/*
+	 * When opening a disk device, we want to preserve the user's original
+	 * intent.  We always want to open the device by the path the user gave
+	 * us, even if it is one of multiple paths to the save device.  But we
+	 * also want to be able to survive disks being removed/recabled.
+	 * Therefore the sequence of opening devices is:
+	 *
+	 * 1. Try opening the device by path.
+	 *
+	 * 	a. First append "s0" to see if this is a whole disk
+	 * 	b. Fall back to path otherwise
+	 *
+	 * 2. If the devid of the device matches the stored value, return
+	 *    success.
+	 *
+	 * 3. Otherwise, the device may have moved.  Try opening the device
+	 *    by the devid instead.
+	 *
+	 */
+	if (vd->vdev_devid != NULL) {
+		if (ddi_devid_str_decode(vd->vdev_devid, &dvd->vd_devid,
+		    &dvd->vd_minor) != 0) {
+			vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
+			return (EINVAL);
+		}
+	}
+
+	error = EINVAL;		/* presume failure */
+
+	if (vd->vdev_path != NULL) {
+		size_t len = strlen(vd->vdev_path) + 3;
+		char *buf = kmem_alloc(len, KM_SLEEP);
+		ddi_devid_t devid;
+
+		(void) snprintf(buf, len, "%ss0", vd->vdev_path);
+
+		/*
+		 * Try whole disk first, then slice name.
+		 */
+		if ((error = ldi_open_by_name(buf, spa_mode, kcred,
+		    &dvd->vd_lh, zfs_li)) != 0)
+			error = ldi_open_by_name(vd->vdev_path,
+			    spa_mode, kcred, &dvd->vd_lh, zfs_li);
+
+		kmem_free(buf, len);
+
+		/*
+		 * Compare the devid to the stored value.
+		 */
+		if (error == 0 && vd->vdev_devid != NULL &&
+		    ldi_get_devid(dvd->vd_lh, &devid) == 0) {
+			if (ddi_devid_compare(devid, dvd->vd_devid) != 0) {
+				error = EINVAL;
+				(void) ldi_close(dvd->vd_lh, spa_mode, kcred);
+				dvd->vd_lh = NULL;
+			}
+			ddi_devid_free(devid);
+		}
+	}
+
+	/*
+	 * If we were unable to open by path, or the devid check fails, open by
+	 * devid instead.
+	 */
+	if (error != 0 && vd->vdev_devid != NULL)
+		error = ldi_open_by_devid(dvd->vd_devid, dvd->vd_minor,
+		    spa_mode, kcred, &dvd->vd_lh, zfs_li);
+
+	if (error) {
+		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
+		return (error);
+	}
+
+	/*
+	 * Determine the actual size of the device.
+	 */
+	if (ldi_get_size(dvd->vd_lh, psize) != 0) {
+		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
+		return (EINVAL);
+	}
+
+	*ashift = SPA_MINBLOCKSHIFT;
+
+	return (0);
+}
+
+static void
+vdev_disk_close(vdev_t *vd)
+{
+	vdev_disk_t *dvd = vd->vdev_tsd;
+
+	if (dvd == NULL)
+		return;
+
+	dprintf("removing disk %s, devid %s\n",
+	    vd->vdev_path ? vd->vdev_path : "<none>",
+	    vd->vdev_devid ? vd->vdev_devid : "<none>");
+
+	if (dvd->vd_minor != NULL)
+		ddi_devid_str_free(dvd->vd_minor);
+
+	if (dvd->vd_devid != NULL)
+		ddi_devid_free(dvd->vd_devid);
+
+	if (dvd->vd_lh != NULL)
+		(void) ldi_close(dvd->vd_lh, spa_mode, kcred);
+
+	kmem_free(dvd, sizeof (vdev_disk_t));
+	vd->vdev_tsd = NULL;
+}
+
+static void
+vdev_disk_io_intr(buf_t *bp)
+{
+	vdev_disk_buf_t *vdb = (vdev_disk_buf_t *)bp;
+	zio_t *zio = vdb->vdb_io;
+
+	if ((zio->io_error = geterror(bp)) == 0 && bp->b_resid != 0)
+		zio->io_error = EIO;
+
+	kmem_free(vdb, sizeof (vdev_disk_buf_t));
+
+	zio_next_stage_async(zio);
+}
+
+static void
+vdev_disk_ioctl_done(void *zio_arg, int error)
+{
+	zio_t *zio = zio_arg;
+
+	zio->io_error = error;
+
+	zio_next_stage_async(zio);
+}
+
+static void
+vdev_disk_io_start(zio_t *zio)
+{
+	vdev_t *vd = zio->io_vd;
+	vdev_disk_t *dvd = vd->vdev_tsd;
+	vdev_disk_buf_t *vdb;
+	buf_t *bp;
+	int flags, error;
+
+	if (zio->io_type == ZIO_TYPE_IOCTL) {
+		zio_vdev_io_bypass(zio);
+
+		/* XXPOLICY */
+		if (vdev_is_dead(vd)) {
+			zio->io_error = ENXIO;
+			zio_next_stage_async(zio);
+			return;
+		}
+
+		switch (zio->io_cmd) {
+
+		case DKIOCFLUSHWRITECACHE:
+
+			zio->io_dk_callback.dkc_callback = vdev_disk_ioctl_done;
+			zio->io_dk_callback.dkc_cookie = zio;
+
+			error = ldi_ioctl(dvd->vd_lh, zio->io_cmd,
+			    (uintptr_t)&zio->io_dk_callback,
+			    FKIOCTL, kcred, NULL);
+
+			if (error == 0) {
+				/*
+				 * The ioctl will be done asychronously,
+				 * and will call vdev_disk_ioctl_done()
+				 * upon completion.
+				 */
+				return;
+			}
+			zio->io_error = error;
+			break;
+
+		default:
+			zio->io_error = ENOTSUP;
+		}
+
+		zio_next_stage_async(zio);
+		return;
+	}
+
+	if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio) == 0)
+		return;
+
+	if ((zio = vdev_queue_io(zio)) == NULL)
+		return;
+
+	flags = (zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE);
+	flags |= B_BUSY | B_NOCACHE;
+	if (zio->io_flags & ZIO_FLAG_FAILFAST)
+		flags |= B_FAILFAST;
+
+	vdb = kmem_alloc(sizeof (vdev_disk_buf_t), KM_SLEEP);
+
+	vdb->vdb_io = zio;
+	bp = &vdb->vdb_buf;
+
+	bioinit(bp);
+	bp->b_flags = flags;
+	bp->b_bcount = zio->io_size;
+	bp->b_un.b_addr = zio->io_data;
+	bp->b_lblkno = lbtodb(zio->io_offset);
+	bp->b_bufsize = zio->io_size;
+	bp->b_iodone = (int (*)())vdev_disk_io_intr;
+
+	/* XXPOLICY */
+	error = vdev_is_dead(vd) ? ENXIO : vdev_error_inject(vd, zio);
+	if (error) {
+		zio->io_error = error;
+		bioerror(bp, error);
+		bp->b_resid = bp->b_bcount;
+		bp->b_iodone(bp);
+		return;
+	}
+
+	error = ldi_strategy(dvd->vd_lh, bp);
+	/* ldi_strategy() will return non-zero only on programming errors */
+	ASSERT(error == 0);
+}
+
+static void
+vdev_disk_io_done(zio_t *zio)
+{
+	vdev_queue_io_done(zio);
+
+	if (zio->io_type == ZIO_TYPE_WRITE)
+		vdev_cache_write(zio);
+
+	zio_next_stage(zio);
+}
+
+vdev_ops_t vdev_disk_ops = {
+	vdev_disk_open,
+	vdev_disk_close,
+	vdev_default_asize,
+	vdev_disk_io_start,
+	vdev_disk_io_done,
+	NULL,
+	VDEV_TYPE_DISK,		/* name of this vdev type */
+	B_TRUE			/* leaf vdev */
+};