Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  exofs: groups support
  exofs: Prepare for groups
  exofs: Error recovery if object is missing from storage
  exofs: convert io_state to use pages array instead of bio at input
  exofs: RAID0 support
  exofs: Define on-disk per-inode optional layout attribute
  exofs: unindent exofs_sbi_read
  exofs: Move layout related members to a layout structure
  exofs: Recover in the case of read-passed-end-of-file
  exofs: Micro-optimize exofs_i_info
  exofs: debug print even less

5 files changed, 779 insertions, 203 deletions

diff --git a/fs/exofs/common.h b/fs/exofs/common.h
index b1b178e6171..f0d520312d8 100644
--- a/fs/exofs/common.h
+++ b/fs/exofs/common.h
@@ -55,6 +55,8 @@
 /* exofs Application specific page/attribute */
 # define EXOFS_APAGE_FS_DATA	(OSD_APAGE_APP_DEFINED_FIRST + 3)
 # define EXOFS_ATTR_INODE_DATA	1
+# define EXOFS_ATTR_INODE_FILE_LAYOUT	2
+# define EXOFS_ATTR_INODE_DIR_LAYOUT	3
 
 /*
  * The maximum number of files we can have is limited by the size of the
@@ -206,4 +208,41 @@ enum {
 	(((name_len) + offsetof(struct exofs_dir_entry, name)  + \
 	  EXOFS_DIR_ROUND) & ~EXOFS_DIR_ROUND)
 
+/*
+ * The on-disk (optional) layout structure.
+ * sits in an EXOFS_ATTR_INODE_FILE_LAYOUT or EXOFS_ATTR_INODE_DIR_LAYOUT
+ * attribute, attached to any inode, usually to a directory.
+ */
+
+enum exofs_inode_layout_gen_functions {
+	LAYOUT_MOVING_WINDOW = 0,
+	LAYOUT_IMPLICT = 1,
+};
+
+struct exofs_on_disk_inode_layout {
+	__le16 gen_func; /* One of enum exofs_inode_layout_gen_functions */
+	__le16 pad;
+	union {
+		/* gen_func == LAYOUT_MOVING_WINDOW (default) */
+		struct exofs_layout_sliding_window {
+			__le32 num_devices; /* first n devices in global-table*/
+		} sliding_window __packed;
+
+		/* gen_func == LAYOUT_IMPLICT */
+		struct exofs_layout_implict_list {
+			struct exofs_dt_data_map data_map;
+			/* Variable array of size data_map.cb_num_comps. These
+			 * are device indexes of the devices in the global table
+			 */
+			__le32 dev_indexes[];
+		} implict __packed;
+	};
+} __packed;
+
+static inline size_t exofs_on_disk_inode_layout_size(unsigned max_devs)
+{
+	return sizeof(struct exofs_on_disk_inode_layout) +
+		max_devs * sizeof(__le32);
+}
+
 #endif /*ifndef __EXOFS_COM_H__*/
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
index c35fd462398..59b8bf2825c 100644
--- a/fs/exofs/exofs.h
+++ b/fs/exofs/exofs.h
@@ -55,12 +55,28 @@
 /* u64 has problems with printk this will cast it to unsigned long long */
 #define _LLU(x) (unsigned long long)(x)
 
+struct exofs_layout {
+	osd_id		s_pid;			/* partition ID of file system*/
+
+	/* Our way of looking at the data_map */
+	unsigned stripe_unit;
+	unsigned mirrors_p1;
+
+	unsigned group_width;
+	u64	 group_depth;
+	unsigned group_count;
+
+	enum exofs_inode_layout_gen_functions lay_func;
+
+	unsigned	s_numdevs;		/* Num of devices in array    */
+	struct osd_dev	*s_ods[0];		/* Variable length            */
+};
+
 /*
  * our extension to the in-memory superblock
  */
 struct exofs_sb_info {
 	struct exofs_fscb s_fscb;		/* Written often, pre-allocate*/
-	osd_id		s_pid;			/* partition ID of file system*/
 	int		s_timeout;		/* timeout for OSD operations */
 	uint64_t	s_nextid;		/* highest object ID used     */
 	uint32_t	s_numfiles;		/* number of files on fs      */
@@ -69,22 +85,27 @@ struct exofs_sb_info {
 	atomic_t	s_curr_pending;		/* number of pending commands */
 	uint8_t		s_cred[OSD_CAP_LEN];	/* credential for the fscb    */
 
-	struct pnfs_osd_data_map data_map;	/* Default raid to use        */
-	unsigned	s_numdevs;		/* Num of devices in array    */
-	struct osd_dev	*s_ods[1];		/* Variable length, minimum 1 */
+	struct pnfs_osd_data_map data_map;	/* Default raid to use
+						 * FIXME: Needed ?
+						 */
+/*	struct exofs_layout	dir_layout;*/	/* Default dir layout */
+	struct exofs_layout	layout;		/* Default files layout,
+						 * contains the variable osd_dev
+						 * array. Keep last */
+	struct osd_dev	*_min_one_dev[1];	/* Place holder for one dev   */
 };
 
 /*
  * our extension to the in-memory inode
  */
 struct exofs_i_info {
+	struct inode   vfs_inode;          /* normal in-memory inode          */
+	wait_queue_head_t i_wq;            /* wait queue for inode            */
 	unsigned long  i_flags;            /* various atomic flags            */
 	uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
 	uint32_t       i_dir_start_lookup; /* which page to start lookup      */
-	wait_queue_head_t i_wq;            /* wait queue for inode            */
 	uint64_t       i_commit_size;      /* the object's written length     */
 	uint8_t        i_cred[OSD_CAP_LEN];/* all-powerful credential         */
-	struct inode   vfs_inode;          /* normal in-memory inode          */
 };
 
 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
@@ -101,7 +122,7 @@ struct exofs_io_state {
 	void			*private;
 	exofs_io_done_fn	done;
 
-	struct exofs_sb_info	*sbi;
+	struct exofs_layout	*layout;
 	struct osd_obj_id	obj;
 	u8			*cred;
 
@@ -109,7 +130,11 @@ struct exofs_io_state {
 	loff_t			offset;
 	unsigned long		length;
 	void			*kern_buff;
-	struct bio		*bio;
+
+	struct page		**pages;
+	unsigned		nr_pages;
+	unsigned		pgbase;
+	unsigned		pages_consumed;
 
 	/* Attributes */
 	unsigned		in_attr_len;
@@ -122,6 +147,9 @@ struct exofs_io_state {
 	struct exofs_per_dev_state {
 		struct osd_request *or;
 		struct bio *bio;
+		loff_t offset;
+		unsigned length;
+		unsigned dev;
 	} per_dev[];
 };
 
@@ -175,6 +203,12 @@ static inline struct exofs_i_info *exofs_i(struct inode *inode)
 }
 
 /*
+ * Given a layout, object_number and stripe_index return the associated global
+ * dev_index
+ */
+unsigned exofs_layout_od_id(struct exofs_layout *layout,
+			    osd_id obj_no, unsigned layout_index);
+/*
  * Maximum count of links to a file
  */
 #define EXOFS_LINK_MAX           32000
@@ -189,7 +223,8 @@ void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
 int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
 		    u64 offset, void *p, unsigned length);
 
-int  exofs_get_io_state(struct exofs_sb_info *sbi, struct exofs_io_state** ios);
+int  exofs_get_io_state(struct exofs_layout *layout,
+			struct exofs_io_state **ios);
 void exofs_put_io_state(struct exofs_io_state *ios);
 
 int exofs_check_io(struct exofs_io_state *ios, u64 *resid);
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index 2afbcebeda7..5514f3c2c2f 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -41,16 +41,18 @@
 
 enum { BIO_MAX_PAGES_KMALLOC =
 		(PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec),
+	MAX_PAGES_KMALLOC =
+		PAGE_SIZE / sizeof(struct page *),
 };
 
 struct page_collect {
 	struct exofs_sb_info *sbi;
-	struct request_queue *req_q;
 	struct inode *inode;
 	unsigned expected_pages;
 	struct exofs_io_state *ios;
 
-	struct bio *bio;
+	struct page **pages;
+	unsigned alloc_pages;
 	unsigned nr_pages;
 	unsigned long length;
 	loff_t pg_first; /* keep 64bit also in 32-arches */
@@ -62,15 +64,12 @@ static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
 	struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
 
 	pcol->sbi = sbi;
-	/* Create master bios on first Q, later on cloning, each clone will be
-	 * allocated on it's destination Q
-	 */
-	pcol->req_q = osd_request_queue(sbi->s_ods[0]);
 	pcol->inode = inode;
 	pcol->expected_pages = expected_pages;
 
 	pcol->ios = NULL;
-	pcol->bio = NULL;
+	pcol->pages = NULL;
+	pcol->alloc_pages = 0;
 	pcol->nr_pages = 0;
 	pcol->length = 0;
 	pcol->pg_first = -1;
@@ -80,7 +79,8 @@ static void _pcol_reset(struct page_collect *pcol)
 {
 	pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
 
-	pcol->bio = NULL;
+	pcol->pages = NULL;
+	pcol->alloc_pages = 0;
 	pcol->nr_pages = 0;
 	pcol->length = 0;
 	pcol->pg_first = -1;
@@ -90,38 +90,43 @@ static void _pcol_reset(struct page_collect *pcol)
 	 * it might not end here. don't be left with nothing
 	 */
 	if (!pcol->expected_pages)
-		pcol->expected_pages = BIO_MAX_PAGES_KMALLOC;
+		pcol->expected_pages = MAX_PAGES_KMALLOC;
 }
 
 static int pcol_try_alloc(struct page_collect *pcol)
 {
-	int pages = min_t(unsigned, pcol->expected_pages,
-			  BIO_MAX_PAGES_KMALLOC);
+	unsigned pages = min_t(unsigned, pcol->expected_pages,
+			  MAX_PAGES_KMALLOC);
 
 	if (!pcol->ios) { /* First time allocate io_state */
-		int ret = exofs_get_io_state(pcol->sbi, &pcol->ios);
+		int ret = exofs_get_io_state(&pcol->sbi->layout, &pcol->ios);
 
 		if (ret)
 			return ret;
 	}
 
+	/* TODO: easily support bio chaining */
+	pages =  min_t(unsigned, pages,
+		       pcol->sbi->layout.group_width * BIO_MAX_PAGES_KMALLOC);
+
 	for (; pages; pages >>= 1) {
-		pcol->bio = bio_kmalloc(GFP_KERNEL, pages);
-		if (likely(pcol->bio))
+		pcol->pages = kmalloc(pages * sizeof(struct page *),
+				      GFP_KERNEL);
+		if (likely(pcol->pages)) {
+			pcol->alloc_pages = pages;
 			return 0;
+		}
 	}
 
-	EXOFS_ERR("Failed to bio_kmalloc expected_pages=%u\n",
+	EXOFS_ERR("Failed to kmalloc expected_pages=%u\n",
 		  pcol->expected_pages);
 	return -ENOMEM;
 }
 
 static void pcol_free(struct page_collect *pcol)
 {
-	if (pcol->bio) {
-		bio_put(pcol->bio);
-		pcol->bio = NULL;
-	}
+	kfree(pcol->pages);
+	pcol->pages = NULL;
 
 	if (pcol->ios) {
 		exofs_put_io_state(pcol->ios);
@@ -132,11 +137,10 @@ static void pcol_free(struct page_collect *pcol)
 static int pcol_add_page(struct page_collect *pcol, struct page *page,
 			 unsigned len)
 {
-	int added_len = bio_add_pc_page(pcol->req_q, pcol->bio, page, len, 0);
-	if (unlikely(len != added_len))
+	if (unlikely(pcol->nr_pages >= pcol->alloc_pages))
 		return -ENOMEM;
 
-	++pcol->nr_pages;
+	pcol->pages[pcol->nr_pages++] = page;
 	pcol->length += len;
 	return 0;
 }
@@ -181,7 +185,6 @@ static void update_write_page(struct page *page, int ret)
  */
 static int __readpages_done(struct page_collect *pcol, bool do_unlock)
 {
-	struct bio_vec *bvec;
 	int i;
 	u64 resid;
 	u64 good_bytes;
@@ -193,13 +196,13 @@ static int __readpages_done(struct page_collect *pcol, bool do_unlock)
 	else
 		good_bytes = pcol->length - resid;
 
-	EXOFS_DBGMSG("readpages_done(0x%lx) good_bytes=0x%llx"
+	EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx"
 		     " length=0x%lx nr_pages=%u\n",
 		     pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 		     pcol->nr_pages);
 
-	__bio_for_each_segment(bvec, pcol->bio, i, 0) {
-		struct page *page = bvec->bv_page;
+	for (i = 0; i < pcol->nr_pages; i++) {
+		struct page *page = pcol->pages[i];
 		struct inode *inode = page->mapping->host;
 		int page_stat;
 
@@ -218,11 +221,11 @@ static int __readpages_done(struct page_collect *pcol, bool do_unlock)
 		ret = update_read_page(page, page_stat);
 		if (do_unlock)
 			unlock_page(page);
-		length += bvec->bv_len;
+		length += PAGE_SIZE;
 	}
 
 	pcol_free(pcol);
-	EXOFS_DBGMSG("readpages_done END\n");
+	EXOFS_DBGMSG2("readpages_done END\n");
 	return ret;
 }
 
@@ -238,11 +241,10 @@ static void readpages_done(struct exofs_io_state *ios, void *p)
 
 static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
 {
-	struct bio_vec *bvec;
 	int i;
 
-	__bio_for_each_segment(bvec, pcol->bio, i, 0) {
-		struct page *page = bvec->bv_page;
+	for (i = 0; i < pcol->nr_pages; i++) {
+		struct page *page = pcol->pages[i];
 
 		if (rw == READ)
 			update_read_page(page, ret);
@@ -260,13 +262,14 @@ static int read_exec(struct page_collect *pcol, bool is_sync)
 	struct page_collect *pcol_copy = NULL;
 	int ret;
 
-	if (!pcol->bio)
+	if (!pcol->pages)
 		return 0;
 
 	/* see comment in _readpage() about sync reads */
 	WARN_ON(is_sync && (pcol->nr_pages != 1));
 
-	ios->bio = pcol->bio;
+	ios->pages = pcol->pages;
+	ios->nr_pages = pcol->nr_pages;
 	ios->length = pcol->length;
 	ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT;
 
@@ -290,7 +293,7 @@ static int read_exec(struct page_collect *pcol, bool is_sync)
 
 	atomic_inc(&pcol->sbi->s_curr_pending);
 
-	EXOFS_DBGMSG("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
+	EXOFS_DBGMSG2("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
 		  ios->obj.id, _LLU(ios->offset), pcol->length);
 
 	/* pages ownership was passed to pcol_copy */
@@ -366,7 +369,7 @@ try_again:
 		goto try_again;
 	}
 
-	if (!pcol->bio) {
+	if (!pcol->pages) {
 		ret = pcol_try_alloc(pcol);
 		if (unlikely(ret))
 			goto fail;
@@ -448,7 +451,6 @@ static int exofs_readpage(struct file *file, struct page *page)
 static void writepages_done(struct exofs_io_state *ios, void *p)
 {
 	struct page_collect *pcol = p;
-	struct bio_vec *bvec;
 	int i;
 	u64 resid;
 	u64  good_bytes;
@@ -462,13 +464,13 @@ static void writepages_done(struct exofs_io_state *ios, void *p)
 	else
 		good_bytes = pcol->length - resid;
 
-	EXOFS_DBGMSG("writepages_done(0x%lx) good_bytes=0x%llx"
+	EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx"
 		     " length=0x%lx nr_pages=%u\n",
 		     pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 		     pcol->nr_pages);
 
-	__bio_for_each_segment(bvec, pcol->bio, i, 0) {
-		struct page *page = bvec->bv_page;
+	for (i = 0; i < pcol->nr_pages; i++) {
+		struct page *page = pcol->pages[i];
 		struct inode *inode = page->mapping->host;
 		int page_stat;
 
@@ -485,12 +487,12 @@ static void writepages_done(struct exofs_io_state *ios, void *p)
 		EXOFS_DBGMSG2("    writepages_done(0x%lx, 0x%lx) status=%d\n",
 			     inode->i_ino, page->index, page_stat);
 
-		length += bvec->bv_len;
+		length += PAGE_SIZE;
 	}
 
 	pcol_free(pcol);
 	kfree(pcol);
-	EXOFS_DBGMSG("writepages_done END\n");
+	EXOFS_DBGMSG2("writepages_done END\n");
 }
 
 static int write_exec(struct page_collect *pcol)
@@ -500,7 +502,7 @@ static int write_exec(struct page_collect *pcol)
 	struct page_collect *pcol_copy = NULL;
 	int ret;
 
-	if (!pcol->bio)
+	if (!pcol->pages)
 		return 0;
 
 	pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
@@ -512,9 +514,8 @@ static int write_exec(struct page_collect *pcol)
 
 	*pcol_copy = *pcol;
 
-	pcol_copy->bio->bi_rw |= (1 << BIO_RW); /* FIXME: bio_set_dir() */
-
-	ios->bio = pcol_copy->bio;
+	ios->pages = pcol_copy->pages;
+	ios->nr_pages = pcol_copy->nr_pages;
 	ios->offset = pcol_copy->pg_first << PAGE_CACHE_SHIFT;
 	ios->length = pcol_copy->length;
 	ios->done = writepages_done;
@@ -527,7 +528,7 @@ static int write_exec(struct page_collect *pcol)
 	}
 
 	atomic_inc(&pcol->sbi->s_curr_pending);
-	EXOFS_DBGMSG("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
+	EXOFS_DBGMSG2("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
 		  pcol->inode->i_ino, pcol->pg_first, _LLU(ios->offset),
 		  pcol->length);
 	/* pages ownership was passed to pcol_copy */
@@ -605,7 +606,7 @@ try_again:
 		goto try_again;
 	}
 
-	if (!pcol->bio) {
+	if (!pcol->pages) {
 		ret = pcol_try_alloc(pcol);
 		if (unlikely(ret))
 			goto fail;
@@ -616,7 +617,7 @@ try_again:
 
 	ret = pcol_add_page(pcol, page, len);
 	if (unlikely(ret)) {
-		EXOFS_DBGMSG("Failed pcol_add_page "
+		EXOFS_DBGMSG2("Failed pcol_add_page "
 			     "nr_pages=%u total_length=0x%lx\n",
 			     pcol->nr_pages, pcol->length);
 
@@ -663,7 +664,7 @@ static int exofs_writepages(struct address_space *mapping,
 	if (expected_pages < 32L)
 		expected_pages = 32L;
 
-	EXOFS_DBGMSG("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
+	EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
 		     "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
 		     mapping->host->i_ino, wbc->range_start, wbc->range_end,
 		     mapping->nrpages, start, end, expected_pages);
@@ -859,20 +860,33 @@ int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
 	return error;
 }
 
+static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
+	EXOFS_APAGE_FS_DATA,
+	EXOFS_ATTR_INODE_FILE_LAYOUT,
+	0);
+static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
+	EXOFS_APAGE_FS_DATA,
+	EXOFS_ATTR_INODE_DIR_LAYOUT,
+	0);
+
 /*
- * Read an inode from the OSD, and return it as is.  We also return the size
- * attribute in the 'obj_size' argument.
+ * Read the Linux inode info from the OSD, and return it as is. In exofs the
+ * inode info is in an application specific page/attribute of the osd-object.
  */
 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
-		    struct exofs_fcb *inode, uint64_t *obj_size)
+		    struct exofs_fcb *inode)
 {
 	struct exofs_sb_info *sbi = sb->s_fs_info;
-	struct osd_attr attrs[2];
+	struct osd_attr attrs[] = {
+		[0] = g_attr_inode_data,
+		[1] = g_attr_inode_file_layout,
+		[2] = g_attr_inode_dir_layout,
+	};
 	struct exofs_io_state *ios;
+	struct exofs_on_disk_inode_layout *layout;
 	int ret;
 
-	*obj_size = ~0;
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
 		return ret;
@@ -882,14 +896,25 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
 	exofs_make_credential(oi->i_cred, &ios->obj);
 	ios->cred = oi->i_cred;
 
-	attrs[0] = g_attr_inode_data;
-	attrs[1] = g_attr_logical_length;
+	attrs[1].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
+	attrs[2].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs);
+
 	ios->in_attr = attrs;
 	ios->in_attr_len = ARRAY_SIZE(attrs);
 
 	ret = exofs_sbi_read(ios);
-	if (ret)
+	if (unlikely(ret)) {
+		EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
+			  _LLU(ios->obj.id), ret);
+		memset(inode, 0, sizeof(*inode));
+		inode->i_mode = 0040000 | (0777 & ~022);
+		/* If object is lost on target we might as well enable it's
+		 * delete.
+		 */
+		if ((ret == -ENOENT) || (ret == -EINVAL))
+			ret = 0;
 		goto out;
+	}
 
 	ret = extract_attr_from_ios(ios, &attrs[0]);
 	if (ret) {
@@ -901,11 +926,33 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
 
 	ret = extract_attr_from_ios(ios, &attrs[1]);
 	if (ret) {
-		EXOFS_ERR("%s: extract_attr of logical_length failed\n",
-			  __func__);
+		EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
+		goto out;
+	}
+	if (attrs[1].len) {
+		layout = attrs[1].val_ptr;
+		if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
+			EXOFS_ERR("%s: unsupported files layout %d\n",
+				__func__, layout->gen_func);
+			ret = -ENOTSUPP;
+			goto out;
+		}
+	}
+
+	ret = extract_attr_from_ios(ios, &attrs[2]);
+	if (ret) {
+		EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
 		goto out;
 	}
-	*obj_size = get_unaligned_be64(attrs[1].val_ptr);
+	if (attrs[2].len) {
+		layout = attrs[2].val_ptr;
+		if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
+			EXOFS_ERR("%s: unsupported meta-data layout %d\n",
+				__func__, layout->gen_func);
+			ret = -ENOTSUPP;
+			goto out;
+		}
+	}
 
 out:
 	exofs_put_io_state(ios);
@@ -925,7 +972,6 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
 	struct exofs_i_info *oi;
 	struct exofs_fcb fcb;
 	struct inode *inode;
-	uint64_t obj_size;
 	int ret;
 
 	inode = iget_locked(sb, ino);
@@ -937,7 +983,7 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
 	__oi_init(oi);
 
 	/* read the inode from the osd */
-	ret = exofs_get_inode(sb, oi, &fcb, &obj_size);
+	ret = exofs_get_inode(sb, oi, &fcb);
 	if (ret)
 		goto bad_inode;
 
@@ -958,13 +1004,6 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
 	inode->i_blkbits = EXOFS_BLKSHIFT;
 	inode->i_generation = le32_to_cpu(fcb.i_generation);
 
-	if ((inode->i_size != obj_size) &&
-		(!exofs_inode_is_fast_symlink(inode))) {
-		EXOFS_ERR("WARNING: Size of inode=%llu != object=%llu\n",
-			  inode->i_size, _LLU(obj_size));
-		/* FIXME: call exofs_inode_recovery() */
-	}
-
 	oi->i_dir_start_lookup = 0;
 
 	if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
@@ -1043,7 +1082,7 @@ static void create_done(struct exofs_io_state *ios, void *p)
 
 	if (unlikely(ret)) {
 		EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
-			  _LLU(exofs_oi_objno(oi)), _LLU(sbi->s_pid));
+			  _LLU(exofs_oi_objno(oi)), _LLU(sbi->layout.s_pid));
 		/*TODO: When FS is corrupted creation can fail, object already
 		 * exist. Get rid of this asynchronous creation, if exist
 		 * increment the obj counter and try the next object. Until we
@@ -1104,7 +1143,7 @@ struct inode *exofs_new_inode(struct inode *dir, int mode)
 
 	mark_inode_dirty(inode);
 
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("exofs_new_inode: exofs_get_io_state failed\n");
 		return ERR_PTR(ret);
@@ -1170,8 +1209,10 @@ static int exofs_update_inode(struct inode *inode, int do_sync)
 	int ret;
 
 	args = kzalloc(sizeof(*args), GFP_KERNEL);
-	if (!args)
+	if (!args) {
+		EXOFS_DBGMSG("Faild kzalloc of args\n");
 		return -ENOMEM;
+	}
 
 	fcb = &args->fcb;
 
@@ -1200,7 +1241,7 @@ static int exofs_update_inode(struct inode *inode, int do_sync)
 	} else
 		memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
 
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
 		goto free_args;
@@ -1234,7 +1275,8 @@ static int exofs_update_inode(struct inode *inode, int do_sync)
 free_args:
 	kfree(args);
 out:
-	EXOFS_DBGMSG("ret=>%d\n", ret);
+	EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
+		     inode->i_ino, do_sync, ret);
 	return ret;
 }
 
@@ -1283,7 +1325,7 @@ void exofs_delete_inode(struct inode *inode)
 
 	clear_inode(inode);
 
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("%s: exofs_get_io_state failed\n", __func__);
 		return;
diff --git a/fs/exofs/ios.c b/fs/exofs/ios.c
index 5bad01fa1f9..5293bc411d1 100644
--- a/fs/exofs/ios.c
+++ b/fs/exofs/ios.c
@@ -23,9 +23,13 @@
  */
 
 #include <scsi/scsi_device.h>
+#include <asm/div64.h>
 
 #include "exofs.h"
 
+#define EXOFS_DBGMSG2(M...) do {} while (0)
+/* #define EXOFS_DBGMSG2 EXOFS_DBGMSG */
+
 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
 {
 	osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
@@ -64,21 +68,24 @@ out:
 	return ret;
 }
 
-int exofs_get_io_state(struct exofs_sb_info *sbi, struct exofs_io_state** pios)
+int exofs_get_io_state(struct exofs_layout *layout,
+		       struct exofs_io_state **pios)
 {
 	struct exofs_io_state *ios;
 
 	/*TODO: Maybe use kmem_cach per sbi of size
-	 * exofs_io_state_size(sbi->s_numdevs)
+	 * exofs_io_state_size(layout->s_numdevs)
 	 */
-	ios = kzalloc(exofs_io_state_size(sbi->s_numdevs), GFP_KERNEL);
+	ios = kzalloc(exofs_io_state_size(layout->s_numdevs), GFP_KERNEL);
 	if (unlikely(!ios)) {
+		EXOFS_DBGMSG("Faild kzalloc bytes=%d\n",
+			     exofs_io_state_size(layout->s_numdevs));
 		*pios = NULL;
 		return -ENOMEM;
 	}
 
-	ios->sbi = sbi;
-	ios->obj.partition = sbi->s_pid;
+	ios->layout = layout;
+	ios->obj.partition = layout->s_pid;
 	*pios = ios;
 	return 0;
 }
@@ -101,6 +108,29 @@ void exofs_put_io_state(struct exofs_io_state *ios)
 	}
 }
 
+unsigned exofs_layout_od_id(struct exofs_layout *layout,
+			    osd_id obj_no, unsigned 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,
+					   unsigned layout_index)
+{
+	return ios->layout->s_ods[
+		exofs_layout_od_id(ios->layout, ios->obj.id, layout_index)];
+}
+
 static void _sync_done(struct exofs_io_state *ios, void *p)
 {
 	struct completion *waiting = p;
@@ -168,6 +198,21 @@ static int exofs_io_execute(struct exofs_io_state *ios)
 	return ret;
 }
 
+static void _clear_bio(struct bio *bio)
+{
+	struct bio_vec *bv;
+	unsigned i;
+
+	__bio_for_each_segment(bv, bio, i, 0) {
+		unsigned this_count = bv->bv_len;
+
+		if (likely(PAGE_SIZE == this_count))
+			clear_highpage(bv->bv_page);
+		else
+			zero_user(bv->bv_page, bv->bv_offset, this_count);
+	}
+}
+
 int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 {
 	enum osd_err_priority acumulated_osd_err = 0;
@@ -176,16 +221,25 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 
 	for (i = 0; i < ios->numdevs; i++) {
 		struct osd_sense_info osi;
-		int ret = osd_req_decode_sense(ios->per_dev[i].or, &osi);
+		struct osd_request *or = ios->per_dev[i].or;
+		int ret;
+
+		if (unlikely(!or))
+			continue;
 
+		ret = osd_req_decode_sense(or, &osi);
 		if (likely(!ret))
 			continue;
 
-		if (unlikely(ret == -EFAULT)) {
-			EXOFS_DBGMSG("%s: EFAULT Need page clear\n", __func__);
-			/*FIXME: All the pages in this device range should:
-			 *	clear_highpage(page);
-			 */
+		if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
+			/* start read offset passed endof file */
+			_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->per_dev[i].offset),
+				_LLU(ios->per_dev[i].length));
+
+			continue; /* we recovered */
 		}
 
 		if (osi.osd_err_pri >= acumulated_osd_err) {
@@ -205,14 +259,259 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 	return acumulated_lin_err;
 }
 
+/*
+ * L - logical offset into the file
+ *
+ * U - The number of bytes in a stripe within a group
+ *
+ *	U = stripe_unit * group_width
+ *
+ * T - The number of bytes striped within a group of component objects
+ *     (before advancing to the next group)
+ *
+ *	T = stripe_unit * group_width * group_depth
+ *
+ * S - The number of bytes striped across all component objects
+ *     before the pattern repeats
+ *
+ *	S = stripe_unit * group_width * group_depth * group_count
+ *
+ * M - The "major" (i.e., across all components) stripe number
+ *
+ *	M = L / S
+ *
+ * G - Counts the groups from the beginning of the major stripe
+ *
+ *	G = (L - (M * S)) / T	[or (L % S) / T]
+ *
+ * H - The byte offset within the group
+ *
+ *	H = (L - (M * S)) % T	[or (L % S) % T]
+ *
+ * N - The "minor" (i.e., across the group) stripe number
+ *
+ *	N = H / U
+ *
+ * C - The component index coresponding to L
+ *
+ *	C = (H - (N * U)) / stripe_unit + G * group_width
+ *	[or (L % U) / stripe_unit + G * group_width]
+ *
+ * O - The component offset coresponding to L
+ *
+ *	O = L % stripe_unit + N * stripe_unit + M * group_depth * stripe_unit
+ */
+struct _striping_info {
+	u64 obj_offset;
+	u64 group_length;
+	u64 total_group_length;
+	u64 Major;
+	unsigned dev;
+	unsigned unit_off;
+};
+
+static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
+			      struct _striping_info *si)
+{
+	u32	stripe_unit = ios->layout->stripe_unit;
+	u32	group_width = ios->layout->group_width;
+	u64	group_depth = ios->layout->group_depth;
+
+	u32	U = stripe_unit * group_width;
+	u64	T = U * group_depth;
+	u64	S = T * ios->layout->group_count;
+	u64	M = div64_u64(file_offset, S);
+
+	/*
+	G = (L - (M * S)) / T
+	H = (L - (M * S)) % T
+	*/
+	u64	LmodS = file_offset - M * S;
+	u32	G = div64_u64(LmodS, T);
+	u64	H = LmodS - G * T;
+
+	u32	N = div_u64(H, U);
+
+	/* "H - (N * U)" is just "H % U" so it's bound to u32 */
+	si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
+	si->dev *= ios->layout->mirrors_p1;
+
+	div_u64_rem(file_offset, stripe_unit, &si->unit_off);
+
+	si->obj_offset = si->unit_off + (N * stripe_unit) +
+				  (M * group_depth * stripe_unit);
+
+	si->group_length = T - H;
+	si->total_group_length = T;
+	si->Major = M;
+}
+
+static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_pg,
+		unsigned pgbase, struct exofs_per_dev_state *per_dev,
+		int cur_len)
+{
+	unsigned pg = *cur_pg;
+	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->nr_pages + 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) {
+		unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
+		unsigned added_len;
+
+		BUG_ON(ios->nr_pages <= pg);
+		cur_len -= pglen;
+
+		added_len = bio_add_pc_page(q, per_dev->bio, ios->pages[pg],
+					    pglen, pgbase);
+		if (unlikely(pglen != added_len))
+			return -ENOMEM;
+		pgbase = 0;
+		++pg;
+	}
+	BUG_ON(cur_len);
+
+	*cur_pg = pg;
+	return 0;
+}
+
+static int _prepare_one_group(struct exofs_io_state *ios, u64 length,
+			      struct _striping_info *si, unsigned first_comp)
+{
+	unsigned stripe_unit = ios->layout->stripe_unit;
+	unsigned mirrors_p1 = ios->layout->mirrors_p1;
+	unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
+	unsigned dev = si->dev;
+	unsigned first_dev = dev - (dev % devs_in_group);
+	unsigned comp = first_comp + (dev - first_dev);
+	unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
+	unsigned cur_pg = ios->pages_consumed;
+	int ret = 0;
+
+	while (length) {
+		struct exofs_per_dev_state *per_dev = &ios->per_dev[comp];
+		unsigned cur_len, page_off = 0;
+
+		if (!per_dev->length) {
+			per_dev->dev = dev;
+			if (dev < si->dev) {
+				per_dev->offset = si->obj_offset + stripe_unit -
+								   si->unit_off;
+				cur_len = stripe_unit;
+			} else if (dev == si->dev) {
+				per_dev->offset = si->obj_offset;
+				cur_len = stripe_unit - si->unit_off;
+				page_off = si->unit_off & ~PAGE_MASK;
+				BUG_ON(page_off && (page_off != ios->pgbase));
+			} else { /* dev > si->dev */
+				per_dev->offset = si->obj_offset - si->unit_off;
+				cur_len = stripe_unit;
+			}
+
+			if (max_comp < comp)
+				max_comp = comp;
+
+			dev += mirrors_p1;
+			dev = (dev % devs_in_group) + first_dev;
+		} else {
+			cur_len = stripe_unit;
+		}
+		if (cur_len >= length)
+			cur_len = length;
+
+		ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
+				       cur_len);
+		if (unlikely(ret))
+			goto out;
+
+		comp += mirrors_p1;
+		comp = (comp % devs_in_group) + first_comp;
+
+		length -= cur_len;
+	}
+out:
+	ios->numdevs = max_comp + mirrors_p1;
+	ios->pages_consumed = cur_pg;
+	return ret;
+}
+
+static int _prepare_for_striping(struct exofs_io_state *ios)
+{
+	u64 length = ios->length;
+	struct _striping_info si;
+	unsigned devs_in_group = ios->layout->group_width *
+				 ios->layout->mirrors_p1;
+	unsigned first_comp = 0;
+	int ret = 0;
+
+	_calc_stripe_info(ios, ios->offset, &si);
+
+	if (!ios->pages) {
+		if (ios->kern_buff) {
+			struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
+
+			per_dev->offset = si.obj_offset;
+			per_dev->dev = si.dev;
+
+			/* no cross device without page array */
+			BUG_ON((ios->layout->group_width > 1) &&
+			       (si.unit_off + ios->length >
+				ios->layout->stripe_unit));
+		}
+		ios->numdevs = ios->layout->mirrors_p1;
+		return 0;
+	}
+
+	while (length) {
+		if (length < si.group_length)
+			si.group_length = length;
+
+		ret = _prepare_one_group(ios, si.group_length, &si, first_comp);
+		if (unlikely(ret))
+			goto out;
+
+		length -= si.group_length;
+
+		si.group_length = si.total_group_length;
+		si.unit_off = 0;
+		++si.Major;
+		si.obj_offset = si.Major * ios->layout->stripe_unit *
+						ios->layout->group_depth;
+
+		si.dev = (si.dev - (si.dev % devs_in_group)) + devs_in_group;
+		si.dev %= ios->layout->s_numdevs;
+
+		first_comp += devs_in_group;
+		first_comp %= ios->layout->s_numdevs;
+	}
+
+out:
+	return ret;
+}
+
 int exofs_sbi_create(struct exofs_io_state *ios)
 {
 	int i, ret;
 
-	for (i = 0; i < ios->sbi->s_numdevs; i++) {
+	for (i = 0; i < ios->layout->s_numdevs; i++) {
 		struct osd_request *or;
 
-		or = osd_start_request(ios->sbi->s_ods[i], GFP_KERNEL);
+		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;
@@ -233,10 +532,10 @@ int exofs_sbi_remove(struct exofs_io_state *ios)
 {
 	int i, ret;
 
-	for (i = 0; i < ios->sbi->s_numdevs; i++) {
+	for (i = 0; i < ios->layout->s_numdevs; i++) {
 		struct osd_request *or;
 
-		or = osd_start_request(ios->sbi->s_ods[i], GFP_KERNEL);
+		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;
@@ -253,51 +552,74 @@ out:
 	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->sbi->s_numdevs; i++) {
+	if (ios->pages && !master_dev->length)
+		return 0; /* Just an empty slot */
+
+	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(ios->sbi->s_ods[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) {
+		if (ios->pages) {
 			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",
+					      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);
-/*			EXOFS_DBGMSG("write sync=%d\n", sync);*/
+			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(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);
-/*			EXOFS_DBGMSG("write_kern sync=%d\n", sync);*/
+			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(per_dev->offset),
+				     _LLU(ios->length), dev);
 		} else {
 			osd_req_set_attributes(or, &ios->obj);
-/*			EXOFS_DBGMSG("set_attributes sync=%d\n", sync);*/
+			EXOFS_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
+				     _LLU(ios->obj.id), ios->out_attr_len, dev);
 		}
 
 		if (ios->out_attr)
@@ -308,54 +630,93 @@ int exofs_sbi_write(struct exofs_io_state *ios)
 			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, ret;
+	int i;
+	int ret;
 
-	for (i = 0; i < 1; i++) {
-		struct osd_request *or;
-		unsigned first_dev = (unsigned)ios->obj.id;
+	ret = _prepare_for_striping(ios);
+	if (unlikely(ret))
+		return ret;
 
-		first_dev %= ios->sbi->s_numdevs;
-		or = osd_start_request(ios->sbi->s_ods[first_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++;
+	for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
+		ret = _sbi_write_mirror(ios, i);
+		if (unlikely(ret))
+			return ret;
+	}
 
-		if (ios->bio) {
-			osd_req_read(or, &ios->obj, ios->offset, ios->bio,
-				     ios->length);
-/*			EXOFS_DBGMSG("read sync=%d\n", sync);*/
-		} else if (ios->kern_buff) {
-			osd_req_read_kern(or, &ios->obj, ios->offset,
-					   ios->kern_buff, ios->length);
-/*			EXOFS_DBGMSG("read_kern sync=%d\n", sync);*/
-		} else {
-			osd_req_get_attributes(or, &ios->obj);
-/*			EXOFS_DBGMSG("get_attributes sync=%d\n", sync);*/
-		}
+	ret = exofs_io_execute(ios);
+	return ret;
+}
 
-		if (ios->out_attr)
-			osd_req_add_set_attr_list(or, ios->out_attr,
-						  ios->out_attr_len);
+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[cur_comp];
+	unsigned first_dev = (unsigned)ios->obj.id;
 
-		if (ios->in_attr)
-			osd_req_add_get_attr_list(or, ios->in_attr,
-						  ios->in_attr_len);
+	if (ios->pages && !per_dev->length)
+		return 0; /* Just an empty slot */
+
+	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;
 	}
-	ret = exofs_io_execute(ios);
+	per_dev->or = or;
+
+	if (ios->pages) {
+		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(per_dev->offset), _LLU(per_dev->length),
+			     first_dev);
+	} else if (ios->kern_buff) {
+		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(per_dev->offset),
+			      _LLU(ios->length), first_dev, ret);
+		if (unlikely(ret))
+			return ret;
+	} else {
+		osd_req_get_attributes(or, &ios->obj);
+		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);
 
-out:
+	if (ios->in_attr)
+		osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
+
+	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;
 }
 
@@ -380,42 +741,82 @@ int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
 	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;
+	struct _striping_info si;
 	int i, ret;
 
-	if (exofs_get_io_state(sbi, &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;
+	_calc_stripe_info(ios, size, &si);
 
-	for (i = 0; i < sbi->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(sbi->s_ods[i], 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++;
+		if (i < si.dev)
+			obj_size = si.obj_offset +
+					ios->layout->stripe_unit - si.unit_off;
+		else if (i == si.dev)
+			obj_size = si.obj_offset;
+		else /* i > si.dev */
+			obj_size = si.obj_offset - si.unit_off;
 
-		osd_req_set_attributes(or, &ios->obj);
-		osd_req_add_set_attr_list(or, &attr, 1);
+		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;
 	}
 	ret = exofs_io_execute(ios);
 
 out:
+	kfree(size_attrs);
 	exofs_put_io_state(ios);
 	return ret;
 }
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index a1d1e77b12e..6cf5e4e84d6 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -210,7 +210,7 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 	sbi = sb->s_fs_info;
 	fscb = &sbi->s_fscb;
 
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (ret)
 		goto out;
 
@@ -264,12 +264,12 @@ static void _exofs_print_device(const char *msg, const char *dev_path,
 
 void exofs_free_sbi(struct exofs_sb_info *sbi)
 {
-	while (sbi->s_numdevs) {
-		int i = --sbi->s_numdevs;
-		struct osd_dev *od = sbi->s_ods[i];
+	while (sbi->layout.s_numdevs) {
+		int i = --sbi->layout.s_numdevs;
+		struct osd_dev *od = sbi->layout.s_ods[i];
 
 		if (od) {
-			sbi->s_ods[i] = NULL;
+			sbi->layout.s_ods[i] = NULL;
 			osduld_put_device(od);
 		}
 	}
@@ -298,7 +298,8 @@ static void exofs_put_super(struct super_block *sb)
 				  msecs_to_jiffies(100));
 	}
 
-	_exofs_print_device("Unmounting", NULL, sbi->s_ods[0], sbi->s_pid);
+	_exofs_print_device("Unmounting", NULL, sbi->layout.s_ods[0],
+			    sbi->layout.s_pid);
 
 	exofs_free_sbi(sbi);
 	sb->s_fs_info = NULL;
@@ -307,6 +308,8 @@ static void exofs_put_super(struct super_block *sb)
 static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 				    struct exofs_device_table *dt)
 {
+	u64 stripe_length;
+
 	sbi->data_map.odm_num_comps   =
 				le32_to_cpu(dt->dt_data_map.cb_num_comps);
 	sbi->data_map.odm_stripe_unit =
@@ -320,14 +323,63 @@ static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 	sbi->data_map.odm_raid_algorithm  =
 				le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 
-/* FIXME: Hard coded mirror only for now. if not so do not mount */
-	if ((sbi->data_map.odm_num_comps != numdevs) ||
-	    (sbi->data_map.odm_stripe_unit != EXOFS_BLKSIZE) ||
-	    (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) ||
-	    (sbi->data_map.odm_mirror_cnt != (numdevs - 1)))
+/* FIXME: Only raid0 for now. if not so, do not mount */
+	if (sbi->data_map.odm_num_comps != numdevs) {
+		EXOFS_ERR("odm_num_comps(%u) != numdevs(%u)\n",
+			  sbi->data_map.odm_num_comps, numdevs);
 		return -EINVAL;
-	else
-		return 0;
+	}
+	if (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) {
+		EXOFS_ERR("Only RAID_0 for now\n");
+		return -EINVAL;
+	}
+	if (0 != (numdevs % (sbi->data_map.odm_mirror_cnt + 1))) {
+		EXOFS_ERR("Data Map wrong, numdevs=%d mirrors=%d\n",
+			  numdevs, sbi->data_map.odm_mirror_cnt);
+		return -EINVAL;
+	}
+
+	if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
+		EXOFS_ERR("Stripe Unit(0x%llx)"
+			  " must be Multples of PAGE_SIZE(0x%lx)\n",
+			  _LLU(sbi->data_map.odm_stripe_unit), PAGE_SIZE);
+		return -EINVAL;
+	}
+
+	sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
+	sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
+
+	if (sbi->data_map.odm_group_width) {
+		sbi->layout.group_width = sbi->data_map.odm_group_width;
+		sbi->layout.group_depth = sbi->data_map.odm_group_depth;
+		if (!sbi->layout.group_depth) {
+			EXOFS_ERR("group_depth == 0 && group_width != 0\n");
+			return -EINVAL;
+		}
+		sbi->layout.group_count = sbi->data_map.odm_num_comps /
+						sbi->layout.mirrors_p1 /
+						sbi->data_map.odm_group_width;
+	} else {
+		if (sbi->data_map.odm_group_depth) {
+			printk(KERN_NOTICE "Warning: group_depth ignored "
+				"group_width == 0 && group_depth == %d\n",
+				sbi->data_map.odm_group_depth);
+			sbi->data_map.odm_group_depth = 0;
+		}
+		sbi->layout.group_width = sbi->data_map.odm_num_comps /
+							sbi->layout.mirrors_p1;
+		sbi->layout.group_depth = -1;
+		sbi->layout.group_count = 1;
+	}
+
+	stripe_length = (u64)sbi->layout.group_width * sbi->layout.stripe_unit;
+	if (stripe_length >= (1ULL << 32)) {
+		EXOFS_ERR("Total Stripe length(0x%llx)"
+			  " >= 32bit is not supported\n", _LLU(stripe_length));
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
 /* @odi is valid only as long as @fscb_dev is valid */
@@ -361,7 +413,7 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 {
 	struct exofs_sb_info *sbi = *psbi;
 	struct osd_dev *fscb_od;
-	struct osd_obj_id obj = {.partition = sbi->s_pid,
+	struct osd_obj_id obj = {.partition = sbi->layout.s_pid,
 				 .id = EXOFS_DEVTABLE_ID};
 	struct exofs_device_table *dt;
 	unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
@@ -376,9 +428,9 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 		return -ENOMEM;
 	}
 
-	fscb_od = sbi->s_ods[0];
-	sbi->s_ods[0] = NULL;
-	sbi->s_numdevs = 0;
+	fscb_od = sbi->layout.s_ods[0];
+	sbi->layout.s_ods[0] = NULL;
+	sbi->layout.s_numdevs = 0;
 	ret = exofs_read_kern(fscb_od, sbi->s_cred, &obj, 0, dt, table_bytes);
 	if (unlikely(ret)) {
 		EXOFS_ERR("ERROR: reading device table\n");
@@ -397,14 +449,15 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 		goto out;
 
 	if (likely(numdevs > 1)) {
-		unsigned size = numdevs * sizeof(sbi->s_ods[0]);
+		unsigned size = numdevs * sizeof(sbi->layout.s_ods[0]);
 
 		sbi = krealloc(sbi, sizeof(*sbi) + size, GFP_KERNEL);
 		if (unlikely(!sbi)) {
 			ret = -ENOMEM;
 			goto out;
 		}
-		memset(&sbi->s_ods[1], 0, size - sizeof(sbi->s_ods[0]));
+		memset(&sbi->layout.s_ods[1], 0,
+		       size - sizeof(sbi->layout.s_ods[0]));
 		*psbi = sbi;
 	}
 
@@ -427,8 +480,8 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 		 * line. We always keep them in device-table order.
 		 */
 		if (fscb_od && osduld_device_same(fscb_od, &odi)) {
-			sbi->s_ods[i] = fscb_od;
-			++sbi->s_numdevs;
+			sbi->layout.s_ods[i] = fscb_od;
+			++sbi->layout.s_numdevs;
 			fscb_od = NULL;
 			continue;
 		}
@@ -441,8 +494,8 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 			goto out;
 		}
 
-		sbi->s_ods[i] = od;
-		++sbi->s_numdevs;
+		sbi->layout.s_ods[i] = od;
+		++sbi->layout.s_numdevs;
 
 		/* Read the fscb of the other devices to make sure the FS
 		 * partition is there.
@@ -499,9 +552,15 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 		goto free_sbi;
 	}
 
-	sbi->s_ods[0] = od;
-	sbi->s_numdevs = 1;
-	sbi->s_pid = opts->pid;
+	/* Default layout in case we do not have a device-table */
+	sbi->layout.stripe_unit = PAGE_SIZE;
+	sbi->layout.mirrors_p1 = 1;
+	sbi->layout.group_width = 1;
+	sbi->layout.group_depth = -1;
+	sbi->layout.group_count = 1;
+	sbi->layout.s_ods[0] = od;
+	sbi->layout.s_numdevs = 1;
+	sbi->layout.s_pid = opts->pid;
 	sbi->s_timeout = opts->timeout;
 
 	/* fill in some other data by hand */
@@ -514,7 +573,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_bdev = NULL;
 	sb->s_dev = 0;
 
-	obj.partition = sbi->s_pid;
+	obj.partition = sbi->layout.s_pid;
 	obj.id = EXOFS_SUPER_ID;
 	exofs_make_credential(sbi->s_cred, &obj);
 
@@ -578,13 +637,13 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 		goto free_sbi;
 	}
 
-	_exofs_print_device("Mounting", opts->dev_name, sbi->s_ods[0],
-			    sbi->s_pid);
+	_exofs_print_device("Mounting", opts->dev_name, sbi->layout.s_ods[0],
+			    sbi->layout.s_pid);
 	return 0;
 
 free_sbi:
 	EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
-		  opts->dev_name, sbi->s_pid, ret);
+		  opts->dev_name, sbi->layout.s_pid, ret);
 	exofs_free_sbi(sbi);
 	return ret;
 }
@@ -627,7 +686,7 @@ static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	uint8_t cred_a[OSD_CAP_LEN];
 	int ret;
 
-	ret = exofs_get_io_state(sbi, &ios);
+	ret = exofs_get_io_state(&sbi->layout, &ios);
 	if (ret) {
 		EXOFS_DBGMSG("exofs_get_io_state failed.\n");
 		return ret;