diff --git a/fs/exofs/ios.c b/fs/exofs/ios.c
index 2b81f99..6e446b2 100644
--- a/fs/exofs/ios.c
+++ b/fs/exofs/ios.c
@@ -23,6 +23,7 @@
  */
 
 #include <scsi/scsi_device.h>
+#include <asm/div64.h>
 
 #include "exofs.h"
 
@@ -110,7 +111,17 @@
 unsigned exofs_layout_od_id(struct exofs_layout *layout,
 			    osd_id obj_no, unsigned layout_index)
 {
-	return layout_index;
+/*	switch (layout->lay_func) {
+	case LAYOUT_MOVING_WINDOW:
+	{*/
+		unsigned dev_mod = obj_no;
+
+		return (layout_index + dev_mod * layout->mirrors_p1) %
+							      layout->s_numdevs;
+/*	}
+	case LAYOUT_FUNC_IMPLICT:
+		return layout->devs[layout_index];
+	}*/
 }
 
 static inline struct osd_dev *exofs_ios_od(struct exofs_io_state *ios,
@@ -225,8 +236,8 @@
 			_clear_bio(ios->per_dev[i].bio);
 			EXOFS_DBGMSG("start read offset passed end of file "
 				"offset=0x%llx, length=0x%llx\n",
-				_LLU(ios->offset),
-				_LLU(ios->length));
+				_LLU(ios->per_dev[i].offset),
+				_LLU(ios->per_dev[i].length));
 
 			continue; /* we recovered */
 		}
@@ -248,6 +259,127 @@
 	return acumulated_lin_err;
 }
 
+/* REMOVEME: After review
+   Some quoteing from the standard
+
+   L = logical offset into the file
+   W = number of data components in a stripe
+   S = W * stripe_unit (S is Stripe length)
+   N = L / S (N is the stripe Number)
+   C = (L-(N*S)) / stripe_unit (C is the component)
+   O = (N*stripe_unit)+(L%stripe_unit) (O is the object's offset)
+*/
+
+static void _offset_dev_unit_off(struct exofs_io_state *ios, u64 file_offset,
+			u64 *obj_offset, unsigned *dev, unsigned *unit_off)
+{
+	unsigned stripe_unit = ios->layout->stripe_unit;
+	unsigned stripe_length = stripe_unit * ios->layout->group_width;
+	u64 stripe_no = file_offset;
+	unsigned stripe_mod = do_div(stripe_no, stripe_length);
+
+	*unit_off = stripe_mod % stripe_unit;
+	*obj_offset = stripe_no * stripe_unit + *unit_off;
+	*dev = stripe_mod / stripe_unit * ios->layout->mirrors_p1;
+}
+
+static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_bvec,
+		     struct exofs_per_dev_state *per_dev, int cur_len)
+{
+	unsigned bv = *cur_bvec;
+	struct request_queue *q =
+			osd_request_queue(exofs_ios_od(ios, per_dev->dev));
+
+	per_dev->length += cur_len;
+
+	if (per_dev->bio == NULL) {
+		unsigned pages_in_stripe = ios->layout->group_width *
+					(ios->layout->stripe_unit / PAGE_SIZE);
+		unsigned bio_size = (ios->bio->bi_vcnt + pages_in_stripe) /
+						ios->layout->group_width;
+
+		per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
+		if (unlikely(!per_dev->bio)) {
+			EXOFS_DBGMSG("Faild to allocate BIO size=%u\n",
+				     bio_size);
+			return -ENOMEM;
+		}
+	}
+
+	while (cur_len > 0) {
+		int added_len;
+		struct bio_vec *bvec = &ios->bio->bi_io_vec[bv];
+
+		BUG_ON(ios->bio->bi_vcnt <= bv);
+		cur_len -= bvec->bv_len;
+
+		added_len = bio_add_pc_page(q, per_dev->bio, bvec->bv_page,
+					    bvec->bv_len, bvec->bv_offset);
+		if (unlikely(bvec->bv_len != added_len))
+			return -ENOMEM;
+		++bv;
+	}
+	BUG_ON(cur_len);
+
+	*cur_bvec = bv;
+	return 0;
+}
+
+static int _prepare_for_striping(struct exofs_io_state *ios)
+{
+	u64 length = ios->length;
+	u64 offset = ios->offset;
+	unsigned stripe_unit = ios->layout->stripe_unit;
+	unsigned comp = 0;
+	unsigned stripes = 0;
+	unsigned cur_bvec = 0;
+	int ret;
+
+	if (!ios->bio) {
+		if (ios->kern_buff) {
+			struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
+			unsigned unit_off;
+
+			_offset_dev_unit_off(ios, offset, &per_dev->offset,
+					     &per_dev->dev, &unit_off);
+			/* no cross device without page array */
+			BUG_ON((ios->layout->group_width > 1) &&
+			       (unit_off + length > stripe_unit));
+		}
+		ios->numdevs = ios->layout->mirrors_p1;
+		return 0;
+	}
+
+	while (length) {
+		struct exofs_per_dev_state *per_dev = &ios->per_dev[comp];
+		unsigned cur_len;
+
+		if (!per_dev->length) {
+			unsigned unit_off;
+
+			_offset_dev_unit_off(ios, offset, &per_dev->offset,
+					     &per_dev->dev, &unit_off);
+			stripes++;
+			cur_len = min_t(u64, stripe_unit - unit_off, length);
+			offset += cur_len;
+		} else {
+			cur_len = min_t(u64, stripe_unit, length);
+		}
+
+		ret = _add_stripe_unit(ios, &cur_bvec, per_dev, cur_len);
+		if (unlikely(ret))
+			goto out;
+
+		comp += ios->layout->mirrors_p1;
+		comp %= ios->layout->s_numdevs;
+
+		length -= cur_len;
+	}
+out:
+	ios->numdevs = stripes * ios->layout->mirrors_p1;
+	return ret;
+}
+
 int exofs_sbi_create(struct exofs_io_state *ios)
 {
 	int i, ret;
@@ -296,61 +428,71 @@
 	return ret;
 }
 
-int exofs_sbi_write(struct exofs_io_state *ios)
+static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
 {
-	int i, ret;
+	struct exofs_per_dev_state *master_dev = &ios->per_dev[cur_comp];
+	unsigned dev = ios->per_dev[cur_comp].dev;
+	unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
+	int ret = 0;
 
-	for (i = 0; i < ios->layout->s_numdevs; i++) {
+	for (; cur_comp < last_comp; ++cur_comp, ++dev) {
+		struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 		struct osd_request *or;
 
-		or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
+		or = osd_start_request(exofs_ios_od(ios, dev), GFP_KERNEL);
 		if (unlikely(!or)) {
 			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 			ret = -ENOMEM;
 			goto out;
 		}
-		ios->per_dev[i].or = or;
-		ios->numdevs++;
+		per_dev->or = or;
+		per_dev->offset = master_dev->offset;
 
 		if (ios->bio) {
 			struct bio *bio;
 
-			if (i != 0) {
+			if (per_dev != master_dev) {
 				bio = bio_kmalloc(GFP_KERNEL,
-						  ios->bio->bi_max_vecs);
+						  master_dev->bio->bi_max_vecs);
 				if (unlikely(!bio)) {
 					EXOFS_DBGMSG(
 					      "Faild to allocate BIO size=%u\n",
-					      ios->bio->bi_max_vecs);
+					      master_dev->bio->bi_max_vecs);
 					ret = -ENOMEM;
 					goto out;
 				}
 
-				__bio_clone(bio, ios->bio);
+				__bio_clone(bio, master_dev->bio);
 				bio->bi_bdev = NULL;
 				bio->bi_next = NULL;
-				ios->per_dev[i].bio =  bio;
+				per_dev->length = master_dev->length;
+				per_dev->bio =  bio;
+				per_dev->dev = dev;
 			} else {
-				bio = ios->bio;
+				bio = master_dev->bio;
+				/* FIXME: bio_set_dir() */
+				bio->bi_rw |= (1 << BIO_RW);
 			}
 
-			osd_req_write(or, &ios->obj, ios->offset, bio,
-				      ios->length);
+			osd_req_write(or, &ios->obj, per_dev->offset, bio,
+				      per_dev->length);
 			EXOFS_DBGMSG("write(0x%llx) offset=0x%llx "
 				      "length=0x%llx dev=%d\n",
-				     _LLU(ios->obj.id), _LLU(ios->offset),
-				     _LLU(ios->length), i);
+				     _LLU(ios->obj.id), _LLU(per_dev->offset),
+				     _LLU(per_dev->length), dev);
 		} else if (ios->kern_buff) {
-			osd_req_write_kern(or, &ios->obj, ios->offset,
+			ret = osd_req_write_kern(or, &ios->obj, per_dev->offset,
 					   ios->kern_buff, ios->length);
+			if (unlikely(ret))
+				goto out;
 			EXOFS_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
 				      "length=0x%llx dev=%d\n",
-				     _LLU(ios->obj.id), _LLU(ios->offset),
-				     _LLU(ios->length), i);
+				     _LLU(ios->obj.id), _LLU(per_dev->offset),
+				     _LLU(ios->length), dev);
 		} else {
 			osd_req_set_attributes(or, &ios->obj);
 			EXOFS_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
-				     _LLU(ios->obj.id), ios->out_attr_len, i);
+				     _LLU(ios->obj.id), ios->out_attr_len, dev);
 		}
 
 		if (ios->out_attr)
@@ -361,40 +503,57 @@
 			osd_req_add_get_attr_list(or, ios->in_attr,
 						  ios->in_attr_len);
 	}
-	ret = exofs_io_execute(ios);
 
 out:
 	return ret;
 }
 
-int exofs_sbi_read(struct exofs_io_state *ios)
+int exofs_sbi_write(struct exofs_io_state *ios)
+{
+	int i;
+	int ret;
+
+	ret = _prepare_for_striping(ios);
+	if (unlikely(ret))
+		return ret;
+
+	for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
+		ret = _sbi_write_mirror(ios, i);
+		if (unlikely(ret))
+			return ret;
+	}
+
+	ret = exofs_io_execute(ios);
+	return ret;
+}
+
+static int _sbi_read_mirror(struct exofs_io_state *ios, unsigned cur_comp)
 {
 	struct osd_request *or;
-	struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
+	struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 	unsigned first_dev = (unsigned)ios->obj.id;
 
-	first_dev %= ios->layout->s_numdevs;
+	first_dev = per_dev->dev + first_dev % ios->layout->mirrors_p1;
 	or = osd_start_request(exofs_ios_od(ios, first_dev), GFP_KERNEL);
 	if (unlikely(!or)) {
 		EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 		return -ENOMEM;
 	}
 	per_dev->or = or;
-	ios->numdevs++;
 
 	if (ios->bio) {
-		osd_req_read(or, &ios->obj, ios->offset, ios->bio, ios->length);
+		osd_req_read(or, &ios->obj, per_dev->offset,
+				per_dev->bio, per_dev->length);
 		EXOFS_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
 			     " dev=%d\n", _LLU(ios->obj.id),
-			     _LLU(ios->offset), _LLU(ios->length),
+			     _LLU(per_dev->offset), _LLU(per_dev->length),
 			     first_dev);
 	} else if (ios->kern_buff) {
-		int ret = osd_req_read_kern(or, &ios->obj, ios->offset,
+		int ret = osd_req_read_kern(or, &ios->obj, per_dev->offset,
 					    ios->kern_buff, ios->length);
-
 		EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 			      "length=0x%llx dev=%d ret=>%d\n",
-			      _LLU(ios->obj.id), _LLU(ios->offset),
+			      _LLU(ios->obj.id), _LLU(per_dev->offset),
 			      _LLU(ios->length), first_dev, ret);
 		if (unlikely(ret))
 			return ret;
@@ -403,14 +562,32 @@
 		EXOFS_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
 			      _LLU(ios->obj.id), ios->in_attr_len, first_dev);
 	}
-
 	if (ios->out_attr)
 		osd_req_add_set_attr_list(or, ios->out_attr, ios->out_attr_len);
 
 	if (ios->in_attr)
 		osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
 
-	return exofs_io_execute(ios);
+	return 0;
+}
+
+int exofs_sbi_read(struct exofs_io_state *ios)
+{
+	int i;
+	int ret;
+
+	ret = _prepare_for_striping(ios);
+	if (unlikely(ret))
+		return ret;
+
+	for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
+		ret = _sbi_read_mirror(ios, i);
+		if (unlikely(ret))
+			return ret;
+	}
+
+	ret = exofs_io_execute(ios);
+	return ret;
 }
 
 int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
@@ -434,42 +611,84 @@
 	return -EIO;
 }
 
+static int _truncate_mirrors(struct exofs_io_state *ios, unsigned cur_comp,
+			     struct osd_attr *attr)
+{
+	int last_comp = cur_comp + ios->layout->mirrors_p1;
+
+	for (; cur_comp < last_comp; ++cur_comp) {
+		struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
+		struct osd_request *or;
+
+		or = osd_start_request(exofs_ios_od(ios, cur_comp), GFP_KERNEL);
+		if (unlikely(!or)) {
+			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+			return -ENOMEM;
+		}
+		per_dev->or = or;
+
+		osd_req_set_attributes(or, &ios->obj);
+		osd_req_add_set_attr_list(or, attr, 1);
+	}
+
+	return 0;
+}
+
 int exofs_oi_truncate(struct exofs_i_info *oi, u64 size)
 {
 	struct exofs_sb_info *sbi = oi->vfs_inode.i_sb->s_fs_info;
 	struct exofs_io_state *ios;
-	struct osd_attr attr;
-	__be64 newsize;
+	struct exofs_trunc_attr {
+		struct osd_attr attr;
+		__be64 newsize;
+	} *size_attrs;
+	u64 this_obj_size;
+	unsigned dev;
+	unsigned unit_off;
 	int i, ret;
 
-	if (exofs_get_io_state(&sbi->layout, &ios))
-		return -ENOMEM;
+	ret = exofs_get_io_state(&sbi->layout, &ios);
+	if (unlikely(ret))
+		return ret;
+
+	size_attrs = kcalloc(ios->layout->group_width, sizeof(*size_attrs),
+			     GFP_KERNEL);
+	if (unlikely(!size_attrs)) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	ios->obj.id = exofs_oi_objno(oi);
 	ios->cred = oi->i_cred;
 
-	newsize = cpu_to_be64(size);
-	attr = g_attr_logical_length;
-	attr.val_ptr = &newsize;
+	ios->numdevs = ios->layout->s_numdevs;
+	_offset_dev_unit_off(ios, size, &this_obj_size, &dev, &unit_off);
 
-	for (i = 0; i < sbi->layout.s_numdevs; i++) {
-		struct osd_request *or;
+	for (i = 0; i < ios->layout->group_width; ++i) {
+		struct exofs_trunc_attr *size_attr = &size_attrs[i];
+		u64 obj_size;
 
-		or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
-		if (unlikely(!or)) {
-			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
-			ret = -ENOMEM;
+		if (i < dev)
+			obj_size = this_obj_size +
+					ios->layout->stripe_unit - unit_off;
+		else if (i == dev)
+			obj_size = this_obj_size;
+		else /* i > dev */
+			obj_size = this_obj_size - unit_off;
+
+		size_attr->newsize = cpu_to_be64(obj_size);
+		size_attr->attr = g_attr_logical_length;
+		size_attr->attr.val_ptr = &size_attr->newsize;
+
+		ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
+					&size_attr->attr);
+		if (unlikely(ret))
 			goto out;
-		}
-		ios->per_dev[i].or = or;
-		ios->numdevs++;
-
-		osd_req_set_attributes(or, &ios->obj);
-		osd_req_add_set_attr_list(or, &attr, 1);
 	}
 	ret = exofs_io_execute(ios);
 
 out:
+	kfree(size_attrs);
 	exofs_put_io_state(ios);
 	return ret;
 }