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

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  ore: Make ore its own module
  exofs: Rename raid engine from exofs/ios.c => ore
  exofs: ios: Move to a per inode components & device-table
  exofs: Move exofs specific osd operations out of ios.c
  exofs: Add offset/length to exofs_get_io_state
  exofs: Fix truncate for the raid-groups case
  exofs: Small cleanup of exofs_fill_super
  exofs: BUG: Avoid sbi realloc
  exofs: Remove pnfs-osd private definitions
  nfs_xdr: Move nfs4_string definition out of #ifdef CONFIG_NFS_V4

7 files changed, 487 insertions, 499 deletions

diff --git a/fs/exofs/Kbuild b/fs/exofs/Kbuild
index 2d0f757fda3e..c5a5855a6c44 100644
--- a/fs/exofs/Kbuild
+++ b/fs/exofs/Kbuild
@@ -12,5 +12,8 @@
 # Kbuild - Gets included from the Kernels Makefile and build system
 #
 
-exofs-y := ios.o inode.o file.o symlink.o namei.o dir.o super.o
+# ore module library
+obj-$(CONFIG_ORE) += ore.o
+
+exofs-y := inode.o file.o symlink.o namei.o dir.o super.o
 obj-$(CONFIG_EXOFS_FS) += exofs.o
diff --git a/fs/exofs/Kconfig b/fs/exofs/Kconfig
index 86194b2f799d..70bae4149291 100644
--- a/fs/exofs/Kconfig
+++ b/fs/exofs/Kconfig
@@ -1,6 +1,10 @@
+config ORE
+	tristate
+
 config EXOFS_FS
 	tristate "exofs: OSD based file system support"
 	depends on SCSI_OSD_ULD
+	select ORE
 	help
 	  EXOFS is a file system that uses an OSD storage device,
 	  as its backing storage.
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
index c965806c2821..f4e442ec7445 100644
--- a/fs/exofs/exofs.h
+++ b/fs/exofs/exofs.h
@@ -36,12 +36,9 @@
 #include <linux/fs.h>
 #include <linux/time.h>
 #include <linux/backing-dev.h>
-#include "common.h"
+#include <scsi/osd_ore.h>
 
-/* FIXME: Remove once pnfs hits mainline
- * #include <linux/exportfs/pnfs_osd_xdr.h>
- */
-#include "pnfs.h"
+#include "common.h"
 
 #define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
 
@@ -56,27 +53,11 @@
 /* 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 backing_dev_info bdi;		/* register our bdi with VFS  */
 	struct exofs_sb_stats s_ess;		/* Written often, pre-allocate*/
 	int		s_timeout;		/* timeout for OSD operations */
 	uint64_t	s_nextid;		/* highest object ID used     */
@@ -84,16 +65,13 @@ struct exofs_sb_info {
 	spinlock_t	s_next_gen_lock;	/* spinlock for gen # update  */
 	u32		s_next_generation;	/* next gen # to use          */
 	atomic_t	s_curr_pending;		/* number of pending commands */
-	uint8_t		s_cred[OSD_CAP_LEN];	/* credential for the fscb    */
-	struct 		backing_dev_info bdi;	/* register our bdi with VFS  */
 
 	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 ore_layout	layout;		/* Default files layout       */
+	struct ore_comp one_comp;		/* id & cred of partition id=0*/
+	struct ore_components comps;		/* comps for the partition    */
 	struct osd_dev	*_min_one_dev[1];	/* Place holder for one dev   */
 };
 
@@ -107,7 +85,8 @@ struct exofs_i_info {
 	uint32_t       i_data[EXOFS_IDATA];/*short symlink names and device #s*/
 	uint32_t       i_dir_start_lookup; /* which page to start lookup      */
 	uint64_t       i_commit_size;      /* the object's written length     */
-	uint8_t        i_cred[OSD_CAP_LEN];/* all-powerful credential         */
+	struct ore_comp one_comp;	   /* same component for all devices  */
+	struct ore_components comps;	   /* inode view of the device table  */
 };
 
 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
@@ -115,52 +94,6 @@ static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
 	return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
 }
 
-struct exofs_io_state;
-typedef void (*exofs_io_done_fn)(struct exofs_io_state *or, void *private);
-
-struct exofs_io_state {
-	struct kref		kref;
-
-	void			*private;
-	exofs_io_done_fn	done;
-
-	struct exofs_layout	*layout;
-	struct osd_obj_id	obj;
-	u8			*cred;
-
-	/* Global read/write IO*/
-	loff_t			offset;
-	unsigned long		length;
-	void			*kern_buff;
-
-	struct page		**pages;
-	unsigned		nr_pages;
-	unsigned		pgbase;
-	unsigned		pages_consumed;
-
-	/* Attributes */
-	unsigned		in_attr_len;
-	struct osd_attr 	*in_attr;
-	unsigned		out_attr_len;
-	struct osd_attr 	*out_attr;
-
-	/* Variable array of size numdevs */
-	unsigned numdevs;
-	struct exofs_per_dev_state {
-		struct osd_request *or;
-		struct bio *bio;
-		loff_t offset;
-		unsigned length;
-		unsigned dev;
-	} per_dev[];
-};
-
-static inline unsigned exofs_io_state_size(unsigned numdevs)
-{
-	return sizeof(struct exofs_io_state) +
-		sizeof(struct exofs_per_dev_state) * numdevs;
-}
-
 /*
  * our inode flags
  */
@@ -205,12 +138,6 @@ 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
@@ -219,44 +146,8 @@ unsigned exofs_layout_od_id(struct exofs_layout *layout,
  * function declarations *
  *************************/
 
-/* ios.c */
-void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
-			   const struct osd_obj_id *obj);
-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_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);
-
-int exofs_sbi_create(struct exofs_io_state *ios);
-int exofs_sbi_remove(struct exofs_io_state *ios);
-int exofs_sbi_write(struct exofs_io_state *ios);
-int exofs_sbi_read(struct exofs_io_state *ios);
-
-int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr);
-
-int exofs_oi_truncate(struct exofs_i_info *oi, u64 new_len);
-static inline int exofs_oi_write(struct exofs_i_info *oi,
-				 struct exofs_io_state *ios)
-{
-	ios->obj.id = exofs_oi_objno(oi);
-	ios->cred = oi->i_cred;
-	return exofs_sbi_write(ios);
-}
-
-static inline int exofs_oi_read(struct exofs_i_info *oi,
-				struct exofs_io_state *ios)
-{
-	ios->obj.id = exofs_oi_objno(oi);
-	ios->cred = oi->i_cred;
-	return exofs_sbi_read(ios);
-}
-
 /* inode.c               */
-unsigned exofs_max_io_pages(struct exofs_layout *layout,
+unsigned exofs_max_io_pages(struct ore_layout *layout,
 			    unsigned expected_pages);
 int exofs_setattr(struct dentry *, struct iattr *);
 int exofs_write_begin(struct file *file, struct address_space *mapping,
@@ -281,6 +172,8 @@ int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
 		    struct inode *);
 
 /* super.c               */
+void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
+			   const struct osd_obj_id *obj);
 int exofs_sbi_write_stats(struct exofs_sb_info *sbi);
 
 /*********************
@@ -295,7 +188,6 @@ extern const struct file_operations exofs_file_operations;
 
 /* inode.c           */
 extern const struct address_space_operations exofs_aops;
-extern const struct osd_attr g_attr_logical_length;
 
 /* namei.c           */
 extern const struct inode_operations exofs_dir_inode_operations;
@@ -305,4 +197,33 @@ extern const struct inode_operations exofs_special_inode_operations;
 extern const struct inode_operations exofs_symlink_inode_operations;
 extern const struct inode_operations exofs_fast_symlink_inode_operations;
 
+/* exofs_init_comps will initialize an ore_components device array
+ * pointing to a single ore_comp struct, and a round-robin view
+ * of the device table.
+ * The first device of each inode is the [inode->ino % num_devices]
+ * and the rest of the devices sequentially following where the
+ * first device is after the last device.
+ * It is assumed that the global device array at @sbi is twice
+ * bigger and that the device table repeats twice.
+ * See: exofs_read_lookup_dev_table()
+ */
+static inline void exofs_init_comps(struct ore_components *comps,
+				    struct ore_comp *one_comp,
+				    struct exofs_sb_info *sbi, osd_id oid)
+{
+	unsigned dev_mod = (unsigned)oid, first_dev;
+
+	one_comp->obj.partition = sbi->one_comp.obj.partition;
+	one_comp->obj.id = oid;
+	exofs_make_credential(one_comp->cred, &one_comp->obj);
+
+	comps->numdevs = sbi->comps.numdevs;
+	comps->single_comp = EC_SINGLE_COMP;
+	comps->comps = one_comp;
+
+	/* Round robin device view of the table */
+	first_dev = (dev_mod * sbi->layout.mirrors_p1) % sbi->comps.numdevs;
+	comps->ods = sbi->comps.ods + first_dev;
+}
+
 #endif
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index 8472c098445d..f39a38fc2349 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -43,7 +43,7 @@ enum { BIO_MAX_PAGES_KMALLOC =
 		PAGE_SIZE / sizeof(struct page *),
 };
 
-unsigned exofs_max_io_pages(struct exofs_layout *layout,
+unsigned exofs_max_io_pages(struct ore_layout *layout,
 			    unsigned expected_pages)
 {
 	unsigned pages = min_t(unsigned, expected_pages, MAX_PAGES_KMALLOC);
@@ -58,7 +58,7 @@ struct page_collect {
 	struct exofs_sb_info *sbi;
 	struct inode *inode;
 	unsigned expected_pages;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 
 	struct page **pages;
 	unsigned alloc_pages;
@@ -110,13 +110,6 @@ static int pcol_try_alloc(struct page_collect *pcol)
 {
 	unsigned pages;
 
-	if (!pcol->ios) { /* First time allocate io_state */
-		int ret = exofs_get_io_state(&pcol->sbi->layout, &pcol->ios);
-
-		if (ret)
-			return ret;
-	}
-
 	/* TODO: easily support bio chaining */
 	pages =  exofs_max_io_pages(&pcol->sbi->layout, pcol->expected_pages);
 
@@ -140,7 +133,7 @@ static void pcol_free(struct page_collect *pcol)
 	pcol->pages = NULL;
 
 	if (pcol->ios) {
-		exofs_put_io_state(pcol->ios);
+		ore_put_io_state(pcol->ios);
 		pcol->ios = NULL;
 	}
 }
@@ -200,7 +193,7 @@ static int __readpages_done(struct page_collect *pcol)
 	u64 resid;
 	u64 good_bytes;
 	u64 length = 0;
-	int ret = exofs_check_io(pcol->ios, &resid);
+	int ret = ore_check_io(pcol->ios, &resid);
 
 	if (likely(!ret))
 		good_bytes = pcol->length;
@@ -241,7 +234,7 @@ static int __readpages_done(struct page_collect *pcol)
 }
 
 /* callback of async reads */
-static void readpages_done(struct exofs_io_state *ios, void *p)
+static void readpages_done(struct ore_io_state *ios, void *p)
 {
 	struct page_collect *pcol = p;
 
@@ -269,20 +262,28 @@ static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
 static int read_exec(struct page_collect *pcol)
 {
 	struct exofs_i_info *oi = exofs_i(pcol->inode);
-	struct exofs_io_state *ios = pcol->ios;
+	struct ore_io_state *ios;
 	struct page_collect *pcol_copy = NULL;
 	int ret;
 
 	if (!pcol->pages)
 		return 0;
 
+	if (!pcol->ios) {
+		int ret = ore_get_rw_state(&pcol->sbi->layout, &oi->comps, true,
+					     pcol->pg_first << PAGE_CACHE_SHIFT,
+					     pcol->length, &pcol->ios);
+
+		if (ret)
+			return ret;
+	}
+
+	ios = pcol->ios;
 	ios->pages = pcol->pages;
 	ios->nr_pages = pcol->nr_pages;
-	ios->length = pcol->length;
-	ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT;
 
 	if (pcol->read_4_write) {
-		exofs_oi_read(oi, pcol->ios);
+		ore_read(pcol->ios);
 		return __readpages_done(pcol);
 	}
 
@@ -295,14 +296,14 @@ static int read_exec(struct page_collect *pcol)
 	*pcol_copy = *pcol;
 	ios->done = readpages_done;
 	ios->private = pcol_copy;
-	ret = exofs_oi_read(oi, ios);
+	ret = ore_read(ios);
 	if (unlikely(ret))
 		goto err;
 
 	atomic_inc(&pcol->sbi->s_curr_pending);
 
 	EXOFS_DBGMSG2("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
-		  ios->obj.id, _LLU(ios->offset), pcol->length);
+		  oi->one_comp.obj.id, _LLU(ios->offset), pcol->length);
 
 	/* pages ownership was passed to pcol_copy */
 	_pcol_reset(pcol);
@@ -457,14 +458,14 @@ static int exofs_readpage(struct file *file, struct page *page)
 }
 
 /* Callback for osd_write. All writes are asynchronous */
-static void writepages_done(struct exofs_io_state *ios, void *p)
+static void writepages_done(struct ore_io_state *ios, void *p)
 {
 	struct page_collect *pcol = p;
 	int i;
 	u64 resid;
 	u64  good_bytes;
 	u64  length = 0;
-	int ret = exofs_check_io(ios, &resid);
+	int ret = ore_check_io(ios, &resid);
 
 	atomic_dec(&pcol->sbi->s_curr_pending);
 
@@ -507,13 +508,21 @@ static void writepages_done(struct exofs_io_state *ios, void *p)
 static int write_exec(struct page_collect *pcol)
 {
 	struct exofs_i_info *oi = exofs_i(pcol->inode);
-	struct exofs_io_state *ios = pcol->ios;
+	struct ore_io_state *ios;
 	struct page_collect *pcol_copy = NULL;
 	int ret;
 
 	if (!pcol->pages)
 		return 0;
 
+	BUG_ON(pcol->ios);
+	ret = ore_get_rw_state(&pcol->sbi->layout, &oi->comps, false,
+				 pcol->pg_first << PAGE_CACHE_SHIFT,
+				 pcol->length, &pcol->ios);
+
+	if (unlikely(ret))
+		goto err;
+
 	pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 	if (!pcol_copy) {
 		EXOFS_ERR("write_exec: Failed to kmalloc(pcol)\n");
@@ -523,16 +532,15 @@ static int write_exec(struct page_collect *pcol)
 
 	*pcol_copy = *pcol;
 
+	ios = pcol->ios;
 	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;
 	ios->private = pcol_copy;
 
-	ret = exofs_oi_write(oi, ios);
+	ret = ore_write(ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("write_exec: exofs_oi_write() Failed\n");
+		EXOFS_ERR("write_exec: ore_write() Failed\n");
 		goto err;
 	}
 
@@ -844,17 +852,15 @@ static inline int exofs_inode_is_fast_symlink(struct inode *inode)
 	return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
 }
 
-const struct osd_attr g_attr_logical_length = ATTR_DEF(
-	OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
-
 static int _do_truncate(struct inode *inode, loff_t newsize)
 {
 	struct exofs_i_info *oi = exofs_i(inode);
+	struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
 	int ret;
 
 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 
-	ret = exofs_oi_truncate(oi, (u64)newsize);
+	ret = ore_truncate(&sbi->layout, &oi->comps, (u64)newsize);
 	if (likely(!ret))
 		truncate_setsize(inode, newsize);
 
@@ -917,30 +923,26 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
 		[1] = g_attr_inode_file_layout,
 		[2] = g_attr_inode_dir_layout,
 	};
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	struct exofs_on_disk_inode_layout *layout;
 	int ret;
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &oi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
+		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 		return ret;
 	}
 
-	ios->obj.id = exofs_oi_objno(oi);
-	exofs_make_credential(oi->i_cred, &ios->obj);
-	ios->cred = oi->i_cred;
-
-	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);
+	attrs[1].len = exofs_on_disk_inode_layout_size(sbi->comps.numdevs);
+	attrs[2].len = exofs_on_disk_inode_layout_size(sbi->comps.numdevs);
 
 	ios->in_attr = attrs;
 	ios->in_attr_len = ARRAY_SIZE(attrs);
 
-	ret = exofs_sbi_read(ios);
+	ret = ore_read(ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
-			  _LLU(ios->obj.id), ret);
+			  _LLU(oi->one_comp.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
@@ -990,7 +992,7 @@ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
 	}
 
 out:
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	return ret;
 }
 
@@ -1016,6 +1018,8 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
 		return inode;
 	oi = exofs_i(inode);
 	__oi_init(oi);
+	exofs_init_comps(&oi->comps, &oi->one_comp, sb->s_fs_info,
+			 exofs_oi_objno(oi));
 
 	/* read the inode from the osd */
 	ret = exofs_get_inode(sb, oi, &fcb);
@@ -1107,21 +1111,22 @@ int __exofs_wait_obj_created(struct exofs_i_info *oi)
  * set the obj_created flag so that other methods know that the object exists on
  * the OSD.
  */
-static void create_done(struct exofs_io_state *ios, void *p)
+static void create_done(struct ore_io_state *ios, void *p)
 {
 	struct inode *inode = p;
 	struct exofs_i_info *oi = exofs_i(inode);
 	struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
 	int ret;
 
-	ret = exofs_check_io(ios, NULL);
-	exofs_put_io_state(ios);
+	ret = ore_check_io(ios, NULL);
+	ore_put_io_state(ios);
 
 	atomic_dec(&sbi->s_curr_pending);
 
 	if (unlikely(ret)) {
 		EXOFS_ERR("object=0x%llx creation failed in pid=0x%llx",
-			  _LLU(exofs_oi_objno(oi)), _LLU(sbi->layout.s_pid));
+			  _LLU(exofs_oi_objno(oi)),
+			  _LLU(oi->one_comp.obj.partition));
 		/*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
@@ -1140,14 +1145,13 @@ static void create_done(struct exofs_io_state *ios, void *p)
  */
 struct inode *exofs_new_inode(struct inode *dir, int mode)
 {
-	struct super_block *sb;
+	struct super_block *sb = dir->i_sb;
+	struct exofs_sb_info *sbi = sb->s_fs_info;
 	struct inode *inode;
 	struct exofs_i_info *oi;
-	struct exofs_sb_info *sbi;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	int ret;
 
-	sb = dir->i_sb;
 	inode = new_inode(sb);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
@@ -1157,8 +1161,6 @@ struct inode *exofs_new_inode(struct inode *dir, int mode)
 
 	set_obj_2bcreated(oi);
 
-	sbi = sb->s_fs_info;
-
 	inode->i_mapping->backing_dev_info = sb->s_bdi;
 	inode_init_owner(inode, dir, mode);
 	inode->i_ino = sbi->s_nextid++;
@@ -1170,25 +1172,24 @@ struct inode *exofs_new_inode(struct inode *dir, int mode)
 	spin_unlock(&sbi->s_next_gen_lock);
 	insert_inode_hash(inode);
 
+	exofs_init_comps(&oi->comps, &oi->one_comp, sb->s_fs_info,
+			 exofs_oi_objno(oi));
 	exofs_sbi_write_stats(sbi); /* Make sure new sbi->s_nextid is on disk */
 
 	mark_inode_dirty(inode);
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &oi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("exofs_new_inode: exofs_get_io_state failed\n");
+		EXOFS_ERR("exofs_new_inode: ore_get_io_state failed\n");
 		return ERR_PTR(ret);
 	}
 
-	ios->obj.id = exofs_oi_objno(oi);
-	exofs_make_credential(oi->i_cred, &ios->obj);
-
 	ios->done = create_done;
 	ios->private = inode;
-	ios->cred = oi->i_cred;
-	ret = exofs_sbi_create(ios);
+
+	ret = ore_create(ios);
 	if (ret) {
-		exofs_put_io_state(ios);
+		ore_put_io_state(ios);
 		return ERR_PTR(ret);
 	}
 	atomic_inc(&sbi->s_curr_pending);
@@ -1207,11 +1208,11 @@ struct updatei_args {
 /*
  * Callback function from exofs_update_inode().
  */
-static void updatei_done(struct exofs_io_state *ios, void *p)
+static void updatei_done(struct ore_io_state *ios, void *p)
 {
 	struct updatei_args *args = p;
 
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 
 	atomic_dec(&args->sbi->s_curr_pending);
 
@@ -1227,7 +1228,7 @@ static int exofs_update_inode(struct inode *inode, int do_sync)
 	struct exofs_i_info *oi = exofs_i(inode);
 	struct super_block *sb = inode->i_sb;
 	struct exofs_sb_info *sbi = sb->s_fs_info;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	struct osd_attr attr;
 	struct exofs_fcb *fcb;
 	struct updatei_args *args;
@@ -1266,9 +1267,9 @@ 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->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &oi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
+		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 		goto free_args;
 	}
 
@@ -1285,13 +1286,13 @@ static int exofs_update_inode(struct inode *inode, int do_sync)
 		ios->private = args;
 	}
 
-	ret = exofs_oi_write(oi, ios);
+	ret = ore_write(ios);
 	if (!do_sync && !ret) {
 		atomic_inc(&sbi->s_curr_pending);
 		goto out; /* deallocation in updatei_done */
 	}
 
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 free_args:
 	kfree(args);
 out:
@@ -1310,11 +1311,11 @@ int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
  * Callback function from exofs_delete_inode() - don't have much cleaning up to
  * do.
  */
-static void delete_done(struct exofs_io_state *ios, void *p)
+static void delete_done(struct ore_io_state *ios, void *p)
 {
 	struct exofs_sb_info *sbi = p;
 
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 
 	atomic_dec(&sbi->s_curr_pending);
 }
@@ -1329,7 +1330,7 @@ void exofs_evict_inode(struct inode *inode)
 	struct exofs_i_info *oi = exofs_i(inode);
 	struct super_block *sb = inode->i_sb;
 	struct exofs_sb_info *sbi = sb->s_fs_info;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	int ret;
 
 	truncate_inode_pages(&inode->i_data, 0);
@@ -1349,20 +1350,19 @@ void exofs_evict_inode(struct inode *inode)
 	/* ignore the error, attempt a remove anyway */
 
 	/* Now Remove the OSD objects */
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &oi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_get_io_state failed\n", __func__);
+		EXOFS_ERR("%s: ore_get_io_state failed\n", __func__);
 		return;
 	}
 
-	ios->obj.id = exofs_oi_objno(oi);
 	ios->done = delete_done;
 	ios->private = sbi;
-	ios->cred = oi->i_cred;
-	ret = exofs_sbi_remove(ios);
+
+	ret = ore_remove(ios);
 	if (ret) {
-		EXOFS_ERR("%s: exofs_sbi_remove failed\n", __func__);
-		exofs_put_io_state(ios);
+		EXOFS_ERR("%s: ore_remove failed\n", __func__);
+		ore_put_io_state(ios);
 		return;
 	}
 	atomic_inc(&sbi->s_curr_pending);
diff --git a/fs/exofs/ios.c b/fs/exofs/ore.c
index f74a2ec027a6..25305af88198 100644
--- a/fs/exofs/ios.c
+++ b/fs/exofs/ore.c
@@ -23,81 +23,87 @@
  */
 
 #include <linux/slab.h>
-#include <scsi/scsi_device.h>
 #include <asm/div64.h>
 
-#include "exofs.h"
+#include <scsi/osd_ore.h>
 
-#define EXOFS_DBGMSG2(M...) do {} while (0)
-/* #define EXOFS_DBGMSG2 EXOFS_DBGMSG */
+#define ORE_ERR(fmt, a...) printk(KERN_ERR "ore: " fmt, ##a)
 
-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);
-}
+#ifdef CONFIG_EXOFS_DEBUG
+#define ORE_DBGMSG(fmt, a...) \
+	printk(KERN_NOTICE "ore @%s:%d: " fmt, __func__, __LINE__, ##a)
+#else
+#define ORE_DBGMSG(fmt, a...) \
+	do { if (0) printk(fmt, ##a); } while (0)
+#endif
 
-int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
-		    u64 offset, void *p, unsigned length)
-{
-	struct osd_request *or = osd_start_request(od, GFP_KERNEL);
-/*	struct osd_sense_info osi = {.key = 0};*/
-	int ret;
+/* u64 has problems with printk this will cast it to unsigned long long */
+#define _LLU(x) (unsigned long long)(x)
 
-	if (unlikely(!or)) {
-		EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
-		return -ENOMEM;
-	}
-	ret = osd_req_read_kern(or, obj, offset, p, length);
-	if (unlikely(ret)) {
-		EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
-		goto out;
-	}
+#define ORE_DBGMSG2(M...) do {} while (0)
+/* #define ORE_DBGMSG2 ORE_DBGMSG */
 
-	ret = osd_finalize_request(or, 0, cred, NULL);
-	if (unlikely(ret)) {
-		EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
-		goto out;
-	}
+MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
+MODULE_DESCRIPTION("Objects Raid Engine ore.ko");
+MODULE_LICENSE("GPL");
 
-	ret = osd_execute_request(or);
-	if (unlikely(ret))
-		EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
-	/* osd_req_decode_sense(or, ret); */
+static u8 *_ios_cred(struct ore_io_state *ios, unsigned index)
+{
+	return ios->comps->comps[index & ios->comps->single_comp].cred;
+}
 
-out:
-	osd_end_request(or);
-	return ret;
+static struct osd_obj_id *_ios_obj(struct ore_io_state *ios, unsigned index)
+{
+	return &ios->comps->comps[index & ios->comps->single_comp].obj;
 }
 
-int exofs_get_io_state(struct exofs_layout *layout,
-		       struct exofs_io_state **pios)
+static struct osd_dev *_ios_od(struct ore_io_state *ios, unsigned index)
 {
-	struct exofs_io_state *ios;
+	return ios->comps->ods[index];
+}
+
+int  ore_get_rw_state(struct ore_layout *layout, struct ore_components *comps,
+		      bool is_reading, u64 offset, u64 length,
+		      struct ore_io_state **pios)
+{
+	struct ore_io_state *ios;
 
 	/*TODO: Maybe use kmem_cach per sbi of size
 	 * exofs_io_state_size(layout->s_numdevs)
 	 */
-	ios = kzalloc(exofs_io_state_size(layout->s_numdevs), GFP_KERNEL);
+	ios = kzalloc(ore_io_state_size(comps->numdevs), GFP_KERNEL);
 	if (unlikely(!ios)) {
-		EXOFS_DBGMSG("Failed kzalloc bytes=%d\n",
-			     exofs_io_state_size(layout->s_numdevs));
+		ORE_DBGMSG("Failed kzalloc bytes=%d\n",
+			     ore_io_state_size(comps->numdevs));
 		*pios = NULL;
 		return -ENOMEM;
 	}
 
 	ios->layout = layout;
-	ios->obj.partition = layout->s_pid;
+	ios->comps = comps;
+	ios->offset = offset;
+	ios->length = length;
+	ios->reading = is_reading;
+
 	*pios = ios;
 	return 0;
 }
+EXPORT_SYMBOL(ore_get_rw_state);
+
+int  ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
+		      struct ore_io_state **ios)
+{
+	return ore_get_rw_state(layout, comps, true, 0, 0, ios);
+}
+EXPORT_SYMBOL(ore_get_io_state);
 
-void exofs_put_io_state(struct exofs_io_state *ios)
+void ore_put_io_state(struct ore_io_state *ios)
 {
 	if (ios) {
 		unsigned i;
 
 		for (i = 0; i < ios->numdevs; i++) {
-			struct exofs_per_dev_state *per_dev = &ios->per_dev[i];
+			struct ore_per_dev_state *per_dev = &ios->per_dev[i];
 
 			if (per_dev->or)
 				osd_end_request(per_dev->or);
@@ -108,31 +114,9 @@ void exofs_put_io_state(struct exofs_io_state *ios)
 		kfree(ios);
 	}
 }
+EXPORT_SYMBOL(ore_put_io_state);
 
-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)
+static void _sync_done(struct ore_io_state *ios, void *p)
 {
 	struct completion *waiting = p;
 
@@ -141,20 +125,20 @@ static void _sync_done(struct exofs_io_state *ios, void *p)
 
 static void _last_io(struct kref *kref)
 {
-	struct exofs_io_state *ios = container_of(
-					kref, struct exofs_io_state, kref);
+	struct ore_io_state *ios = container_of(
+					kref, struct ore_io_state, kref);
 
 	ios->done(ios, ios->private);
 }
 
 static void _done_io(struct osd_request *or, void *p)
 {
-	struct exofs_io_state *ios = p;
+	struct ore_io_state *ios = p;
 
 	kref_put(&ios->kref, _last_io);
 }
 
-static int exofs_io_execute(struct exofs_io_state *ios)
+static int ore_io_execute(struct ore_io_state *ios)
 {
 	DECLARE_COMPLETION_ONSTACK(wait);
 	bool sync = (ios->done == NULL);
@@ -170,9 +154,9 @@ static int exofs_io_execute(struct exofs_io_state *ios)
 		if (unlikely(!or))
 			continue;
 
-		ret = osd_finalize_request(or, 0, ios->cred, NULL);
+		ret = osd_finalize_request(or, 0, _ios_cred(ios, i), NULL);
 		if (unlikely(ret)) {
-			EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n",
+			ORE_DBGMSG("Failed to osd_finalize_request() => %d\n",
 				     ret);
 			return ret;
 		}
@@ -194,7 +178,7 @@ static int exofs_io_execute(struct exofs_io_state *ios)
 
 	if (sync) {
 		wait_for_completion(&wait);
-		ret = exofs_check_io(ios, NULL);
+		ret = ore_check_io(ios, NULL);
 	}
 	return ret;
 }
@@ -214,7 +198,7 @@ static void _clear_bio(struct bio *bio)
 	}
 }
 
-int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
+int ore_check_io(struct ore_io_state *ios, u64 *resid)
 {
 	enum osd_err_priority acumulated_osd_err = 0;
 	int acumulated_lin_err = 0;
@@ -235,7 +219,7 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 		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 "
+			ORE_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));
@@ -259,6 +243,7 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 
 	return acumulated_lin_err;
 }
+EXPORT_SYMBOL(ore_check_io);
 
 /*
  * L - logical offset into the file
@@ -305,20 +290,21 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 struct _striping_info {
 	u64 obj_offset;
 	u64 group_length;
+	u64 M; /* for truncate */
 	unsigned dev;
 	unsigned unit_off;
 };
 
-static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
+static void _calc_stripe_info(struct ore_layout *layout, 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	stripe_unit = layout->stripe_unit;
+	u32	group_width = layout->group_width;
+	u64	group_depth = layout->group_depth;
 
 	u32	U = stripe_unit * group_width;
 	u64	T = U * group_depth;
-	u64	S = T * ios->layout->group_count;
+	u64	S = T * layout->group_count;
 	u64	M = div64_u64(file_offset, S);
 
 	/*
@@ -333,7 +319,7 @@ static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
 
 	/* "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;
+	si->dev *= layout->mirrors_p1;
 
 	div_u64_rem(file_offset, stripe_unit, &si->unit_off);
 
@@ -341,15 +327,16 @@ static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
 				  (M * group_depth * stripe_unit);
 
 	si->group_length = T - H;
+	si->M = M;
 }
 
-static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_pg,
-		unsigned pgbase, struct exofs_per_dev_state *per_dev,
+static int _add_stripe_unit(struct ore_io_state *ios,  unsigned *cur_pg,
+		unsigned pgbase, struct ore_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));
+			osd_request_queue(_ios_od(ios, per_dev->dev));
 
 	per_dev->length += cur_len;
 
@@ -361,7 +348,7 @@ static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_pg,
 
 		per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
 		if (unlikely(!per_dev->bio)) {
-			EXOFS_DBGMSG("Failed to allocate BIO size=%u\n",
+			ORE_DBGMSG("Failed to allocate BIO size=%u\n",
 				     bio_size);
 			return -ENOMEM;
 		}
@@ -387,7 +374,7 @@ static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_pg,
 	return 0;
 }
 
-static int _prepare_one_group(struct exofs_io_state *ios, u64 length,
+static int _prepare_one_group(struct ore_io_state *ios, u64 length,
 			      struct _striping_info *si)
 {
 	unsigned stripe_unit = ios->layout->stripe_unit;
@@ -400,7 +387,7 @@ static int _prepare_one_group(struct exofs_io_state *ios, u64 length,
 	int ret = 0;
 
 	while (length) {
-		struct exofs_per_dev_state *per_dev = &ios->per_dev[dev];
+		struct ore_per_dev_state *per_dev = &ios->per_dev[dev];
 		unsigned cur_len, page_off = 0;
 
 		if (!per_dev->length) {
@@ -443,7 +430,7 @@ out:
 	return ret;
 }
 
-static int _prepare_for_striping(struct exofs_io_state *ios)
+static int _prepare_for_striping(struct ore_io_state *ios)
 {
 	u64 length = ios->length;
 	u64 offset = ios->offset;
@@ -452,9 +439,9 @@ static int _prepare_for_striping(struct exofs_io_state *ios)
 
 	if (!ios->pages) {
 		if (ios->kern_buff) {
-			struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
+			struct ore_per_dev_state *per_dev = &ios->per_dev[0];
 
-			_calc_stripe_info(ios, ios->offset, &si);
+			_calc_stripe_info(ios->layout, ios->offset, &si);
 			per_dev->offset = si.obj_offset;
 			per_dev->dev = si.dev;
 
@@ -468,7 +455,7 @@ static int _prepare_for_striping(struct exofs_io_state *ios)
 	}
 
 	while (length) {
-		_calc_stripe_info(ios, offset, &si);
+		_calc_stripe_info(ios->layout, offset, &si);
 
 		if (length < si.group_length)
 			si.group_length = length;
@@ -485,57 +472,59 @@ out:
 	return ret;
 }
 
-int exofs_sbi_create(struct exofs_io_state *ios)
+int ore_create(struct ore_io_state *ios)
 {
 	int i, ret;
 
-	for (i = 0; i < ios->layout->s_numdevs; i++) {
+	for (i = 0; i < ios->comps->numdevs; i++) {
 		struct osd_request *or;
 
-		or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
+		or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
 		if (unlikely(!or)) {
-			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+			ORE_ERR("%s: osd_start_request failed\n", __func__);
 			ret = -ENOMEM;
 			goto out;
 		}
 		ios->per_dev[i].or = or;
 		ios->numdevs++;
 
-		osd_req_create_object(or, &ios->obj);
+		osd_req_create_object(or, _ios_obj(ios, i));
 	}
-	ret = exofs_io_execute(ios);
+	ret = ore_io_execute(ios);
 
 out:
 	return ret;
 }
+EXPORT_SYMBOL(ore_create);
 
-int exofs_sbi_remove(struct exofs_io_state *ios)
+int ore_remove(struct ore_io_state *ios)
 {
 	int i, ret;
 
-	for (i = 0; i < ios->layout->s_numdevs; i++) {
+	for (i = 0; i < ios->comps->numdevs; i++) {
 		struct osd_request *or;
 
-		or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
+		or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
 		if (unlikely(!or)) {
-			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+			ORE_ERR("%s: osd_start_request failed\n", __func__);
 			ret = -ENOMEM;
 			goto out;
 		}
 		ios->per_dev[i].or = or;
 		ios->numdevs++;
 
-		osd_req_remove_object(or, &ios->obj);
+		osd_req_remove_object(or, _ios_obj(ios, i));
 	}
-	ret = exofs_io_execute(ios);
+	ret = ore_io_execute(ios);
 
 out:
 	return ret;
 }
+EXPORT_SYMBOL(ore_remove);
 
-static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
+static int _write_mirror(struct ore_io_state *ios, int cur_comp)
 {
-	struct exofs_per_dev_state *master_dev = &ios->per_dev[cur_comp];
+	struct ore_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;
@@ -544,12 +533,12 @@ static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
 		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 ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 		struct osd_request *or;
 
-		or = osd_start_request(exofs_ios_od(ios, dev), GFP_KERNEL);
+		or = osd_start_request(_ios_od(ios, dev), GFP_KERNEL);
 		if (unlikely(!or)) {
-			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+			ORE_ERR("%s: osd_start_request failed\n", __func__);
 			ret = -ENOMEM;
 			goto out;
 		}
@@ -563,7 +552,7 @@ static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
 				bio = bio_kmalloc(GFP_KERNEL,
 						  master_dev->bio->bi_max_vecs);
 				if (unlikely(!bio)) {
-					EXOFS_DBGMSG(
+					ORE_DBGMSG(
 					      "Failed to allocate BIO size=%u\n",
 					      master_dev->bio->bi_max_vecs);
 					ret = -ENOMEM;
@@ -582,25 +571,29 @@ static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
 				bio->bi_rw |= REQ_WRITE;
 			}
 
-			osd_req_write(or, &ios->obj, per_dev->offset, bio,
-				      per_dev->length);
-			EXOFS_DBGMSG("write(0x%llx) offset=0x%llx "
+			osd_req_write(or, _ios_obj(ios, dev), per_dev->offset,
+				      bio, per_dev->length);
+			ORE_DBGMSG("write(0x%llx) offset=0x%llx "
 				      "length=0x%llx dev=%d\n",
-				     _LLU(ios->obj.id), _LLU(per_dev->offset),
+				     _LLU(_ios_obj(ios, dev)->id),
+				     _LLU(per_dev->offset),
 				     _LLU(per_dev->length), dev);
 		} else if (ios->kern_buff) {
-			ret = osd_req_write_kern(or, &ios->obj, per_dev->offset,
-					   ios->kern_buff, ios->length);
+			ret = osd_req_write_kern(or, _ios_obj(ios, dev),
+						 per_dev->offset,
+						 ios->kern_buff, ios->length);
 			if (unlikely(ret))
 				goto out;
-			EXOFS_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
+			ORE_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
 				      "length=0x%llx dev=%d\n",
-				     _LLU(ios->obj.id), _LLU(per_dev->offset),
+				     _LLU(_ios_obj(ios, dev)->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, dev);
+			osd_req_set_attributes(or, _ios_obj(ios, dev));
+			ORE_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
+				     _LLU(_ios_obj(ios, dev)->id),
+				     ios->out_attr_len, dev);
 		}
 
 		if (ios->out_attr)
@@ -616,7 +609,7 @@ out:
 	return ret;
 }
 
-int exofs_sbi_write(struct exofs_io_state *ios)
+int ore_write(struct ore_io_state *ios)
 {
 	int i;
 	int ret;
@@ -626,52 +619,55 @@ int exofs_sbi_write(struct exofs_io_state *ios)
 		return ret;
 
 	for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
-		ret = _sbi_write_mirror(ios, i);
+		ret = _write_mirror(ios, i);
 		if (unlikely(ret))
 			return ret;
 	}
 
-	ret = exofs_io_execute(ios);
+	ret = ore_io_execute(ios);
 	return ret;
 }
+EXPORT_SYMBOL(ore_write);
 
-static int _sbi_read_mirror(struct exofs_io_state *ios, unsigned cur_comp)
+static int _read_mirror(struct ore_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;
+	struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
+	struct osd_obj_id *obj = _ios_obj(ios, cur_comp);
+	unsigned first_dev = (unsigned)obj->id;
 
 	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);
+	or = osd_start_request(_ios_od(ios, first_dev), GFP_KERNEL);
 	if (unlikely(!or)) {
-		EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+		ORE_ERR("%s: osd_start_request failed\n", __func__);
 		return -ENOMEM;
 	}
 	per_dev->or = or;
 
 	if (ios->pages) {
-		osd_req_read(or, &ios->obj, per_dev->offset,
+		osd_req_read(or, 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),
+		ORE_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
+			     " dev=%d\n", _LLU(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,
+		int ret = osd_req_read_kern(or, obj, per_dev->offset,
 					    ios->kern_buff, ios->length);
-		EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
+		ORE_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(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);
+		osd_req_get_attributes(or, obj);
+		ORE_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
+			      _LLU(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);
@@ -682,7 +678,7 @@ static int _sbi_read_mirror(struct exofs_io_state *ios, unsigned cur_comp)
 	return 0;
 }
 
-int exofs_sbi_read(struct exofs_io_state *ios)
+int ore_read(struct ore_io_state *ios)
 {
 	int i;
 	int ret;
@@ -692,16 +688,17 @@ int exofs_sbi_read(struct exofs_io_state *ios)
 		return ret;
 
 	for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
-		ret = _sbi_read_mirror(ios, i);
+		ret = _read_mirror(ios, i);
 		if (unlikely(ret))
 			return ret;
 	}
 
-	ret = exofs_io_execute(ios);
+	ret = ore_io_execute(ios);
 	return ret;
 }
+EXPORT_SYMBOL(ore_read);
 
-int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
+int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr)
 {
 	struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
 	void *iter = NULL;
@@ -721,83 +718,118 @@ int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
 
 	return -EIO;
 }
+EXPORT_SYMBOL(extract_attr_from_ios);
 
-static int _truncate_mirrors(struct exofs_io_state *ios, unsigned cur_comp,
+static int _truncate_mirrors(struct ore_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 ore_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);
+		or = osd_start_request(_ios_od(ios, cur_comp), GFP_KERNEL);
 		if (unlikely(!or)) {
-			EXOFS_ERR("%s: osd_start_request failed\n", __func__);
+			ORE_ERR("%s: osd_start_request failed\n", __func__);
 			return -ENOMEM;
 		}
 		per_dev->or = or;
 
-		osd_req_set_attributes(or, &ios->obj);
+		osd_req_set_attributes(or, _ios_obj(ios, cur_comp));
 		osd_req_add_set_attr_list(or, attr, 1);
 	}
 
 	return 0;
 }
 
-int exofs_oi_truncate(struct exofs_i_info *oi, u64 size)
+struct _trunc_info {
+	struct _striping_info si;
+	u64 prev_group_obj_off;
+	u64 next_group_obj_off;
+
+	unsigned first_group_dev;
+	unsigned nex_group_dev;
+	unsigned max_devs;
+};
+
+void _calc_trunk_info(struct ore_layout *layout, u64 file_offset,
+		       struct _trunc_info *ti)
+{
+	unsigned stripe_unit = layout->stripe_unit;
+
+	_calc_stripe_info(layout, file_offset, &ti->si);
+
+	ti->prev_group_obj_off = ti->si.M * stripe_unit;
+	ti->next_group_obj_off = ti->si.M ? (ti->si.M - 1) * stripe_unit : 0;
+
+	ti->first_group_dev = ti->si.dev - (ti->si.dev % layout->group_width);
+	ti->nex_group_dev = ti->first_group_dev + layout->group_width;
+	ti->max_devs = layout->group_width * layout->group_count;
+}
+
+int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
+		   u64 size)
 {
-	struct exofs_sb_info *sbi = oi->vfs_inode.i_sb->s_fs_info;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	struct exofs_trunc_attr {
 		struct osd_attr attr;
 		__be64 newsize;
 	} *size_attrs;
-	struct _striping_info si;
+	struct _trunc_info ti;
 	int i, ret;
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(layout, comps, &ios);
 	if (unlikely(ret))
 		return ret;
 
-	size_attrs = kcalloc(ios->layout->group_width, sizeof(*size_attrs),
+	_calc_trunk_info(ios->layout, size, &ti);
+
+	size_attrs = kcalloc(ti.max_devs, 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;
+	ios->numdevs = ios->comps->numdevs;
 
-	ios->numdevs = ios->layout->s_numdevs;
-	_calc_stripe_info(ios, size, &si);
-
-	for (i = 0; i < ios->layout->group_width; ++i) {
+	for (i = 0; i < ti.max_devs; ++i) {
 		struct exofs_trunc_attr *size_attr = &size_attrs[i];
 		u64 obj_size;
 
-		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;
+		if (i < ti.first_group_dev)
+			obj_size = ti.prev_group_obj_off;
+		else if (i >= ti.nex_group_dev)
+			obj_size = ti.next_group_obj_off;
+		else if (i < ti.si.dev) /* dev within this group */
+			obj_size = ti.si.obj_offset +
+				      ios->layout->stripe_unit - ti.si.unit_off;
+		else if (i == ti.si.dev)
+			obj_size = ti.si.obj_offset;
+		else /* i > ti.dev */
+			obj_size = ti.si.obj_offset - ti.si.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;
 
+		ORE_DBGMSG("trunc(0x%llx) obj_offset=0x%llx dev=%d\n",
+			     _LLU(comps->comps->obj.id), _LLU(obj_size), i);
 		ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
 					&size_attr->attr);
 		if (unlikely(ret))
 			goto out;
 	}
-	ret = exofs_io_execute(ios);
+	ret = ore_io_execute(ios);
 
 out:
 	kfree(size_attrs);
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	return ret;
 }
+EXPORT_SYMBOL(ore_truncate);
+
+const struct osd_attr g_attr_logical_length = ATTR_DEF(
+	OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
+EXPORT_SYMBOL(g_attr_logical_length);
diff --git a/fs/exofs/pnfs.h b/fs/exofs/pnfs.h
deleted file mode 100644
index c52e9888b8ab..000000000000
--- a/fs/exofs/pnfs.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * Copyright (C) 2008, 2009
- * Boaz Harrosh <bharrosh@panasas.com>
- *
- * This file is part of exofs.
- *
- * exofs is free software; you can redistribute it and/or modify it under the
- * terms of the GNU General Public License  version 2 as published by the Free
- * Software Foundation.
- *
- */
-
-/* FIXME: Remove this file once pnfs hits mainline */
-
-#ifndef __EXOFS_PNFS_H__
-#define __EXOFS_PNFS_H__
-
-#if ! defined(__PNFS_OSD_XDR_H__)
-
-enum pnfs_iomode {
-	IOMODE_READ = 1,
-	IOMODE_RW = 2,
-	IOMODE_ANY = 3,
-};
-
-/* Layout Structure */
-enum pnfs_osd_raid_algorithm4 {
-	PNFS_OSD_RAID_0		= 1,
-	PNFS_OSD_RAID_4		= 2,
-	PNFS_OSD_RAID_5		= 3,
-	PNFS_OSD_RAID_PQ	= 4     /* Reed-Solomon P+Q */
-};
-
-struct pnfs_osd_data_map {
-	u32	odm_num_comps;
-	u64	odm_stripe_unit;
-	u32	odm_group_width;
-	u32	odm_group_depth;
-	u32	odm_mirror_cnt;
-	u32	odm_raid_algorithm;
-};
-
-#endif /* ! defined(__PNFS_OSD_XDR_H__) */
-
-#endif /* __EXOFS_PNFS_H__ */
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index c57beddcc217..274894053b02 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -40,6 +40,8 @@
 
 #include "exofs.h"
 
+#define EXOFS_DBGMSG2(M...) do {} while (0)
+
 /******************************************************************************
  * MOUNT OPTIONS
  *****************************************************************************/
@@ -208,10 +210,48 @@ static void destroy_inodecache(void)
 }
 
 /******************************************************************************
- * SUPERBLOCK FUNCTIONS
+ * Some osd helpers
  *****************************************************************************/
-static const struct super_operations exofs_sops;
-static const struct export_operations exofs_export_ops;
+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);
+}
+
+static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
+		    u64 offset, void *p, unsigned length)
+{
+	struct osd_request *or = osd_start_request(od, GFP_KERNEL);
+/*	struct osd_sense_info osi = {.key = 0};*/
+	int ret;
+
+	if (unlikely(!or)) {
+		EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
+		return -ENOMEM;
+	}
+	ret = osd_req_read_kern(or, obj, offset, p, length);
+	if (unlikely(ret)) {
+		EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
+		goto out;
+	}
+
+	ret = osd_finalize_request(or, 0, cred, NULL);
+	if (unlikely(ret)) {
+		EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
+		goto out;
+	}
+
+	ret = osd_execute_request(or);
+	if (unlikely(ret))
+		EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
+	/* osd_req_decode_sense(or, ret); */
+
+out:
+	osd_end_request(or);
+	EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
+		      "length=0x%llx dev=%p ret=>%d\n",
+		      _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
+	return ret;
+}
 
 static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
 	EXOFS_APAGE_SB_DATA,
@@ -223,21 +263,19 @@ static int __sbi_read_stats(struct exofs_sb_info *sbi)
 	struct osd_attr attrs[] = {
 		[0] = g_attr_sb_stats,
 	};
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	int ret;
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
+		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 		return ret;
 	}
 
-	ios->cred = sbi->s_cred;
-
 	ios->in_attr = attrs;
 	ios->in_attr_len = ARRAY_SIZE(attrs);
 
-	ret = exofs_sbi_read(ios);
+	ret = ore_read(ios);
 	if (unlikely(ret)) {
 		EXOFS_ERR("Error reading super_block stats => %d\n", ret);
 		goto out;
@@ -264,13 +302,13 @@ static int __sbi_read_stats(struct exofs_sb_info *sbi)
 	}
 
 out:
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	return ret;
 }
 
-static void stats_done(struct exofs_io_state *ios, void *p)
+static void stats_done(struct ore_io_state *ios, void *p)
 {
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	/* Good thanks nothing to do anymore */
 }
 
@@ -280,12 +318,12 @@ int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
 	struct osd_attr attrs[] = {
 		[0] = g_attr_sb_stats,
 	};
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	int ret;
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__);
+		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 		return ret;
 	}
 
@@ -293,21 +331,27 @@ int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
 	sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
 	attrs[0].val_ptr = &sbi->s_ess;
 
-	ios->cred = sbi->s_cred;
+
 	ios->done = stats_done;
 	ios->private = sbi;
 	ios->out_attr = attrs;
 	ios->out_attr_len = ARRAY_SIZE(attrs);
 
-	ret = exofs_sbi_write(ios);
+	ret = ore_write(ios);
 	if (unlikely(ret)) {
-		EXOFS_ERR("%s: exofs_sbi_write failed.\n", __func__);
-		exofs_put_io_state(ios);
+		EXOFS_ERR("%s: ore_write failed.\n", __func__);
+		ore_put_io_state(ios);
 	}
 
 	return ret;
 }
 
+/******************************************************************************
+ * SUPERBLOCK FUNCTIONS
+ *****************************************************************************/
+static const struct super_operations exofs_sops;
+static const struct export_operations exofs_export_ops;
+
 /*
  * Write the superblock to the OSD
  */
@@ -315,7 +359,9 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 {
 	struct exofs_sb_info *sbi;
 	struct exofs_fscb *fscb;
-	struct exofs_io_state *ios;
+	struct ore_comp one_comp;
+	struct ore_components comps;
+	struct ore_io_state *ios;
 	int ret = -ENOMEM;
 
 	fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
@@ -331,7 +377,10 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 	 * version). Otherwise the exofs_fscb is read-only from mkfs time. All
 	 * the writeable info is set in exofs_sbi_write_stats() above.
 	 */
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+
+	exofs_init_comps(&comps, &one_comp, sbi, EXOFS_SUPER_ID);
+
+	ret = ore_get_io_state(&sbi->layout, &comps, &ios);
 	if (unlikely(ret))
 		goto out;
 
@@ -345,14 +394,12 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 	fscb->s_newfs = 0;
 	fscb->s_version = EXOFS_FSCB_VER;
 
-	ios->obj.id = EXOFS_SUPER_ID;
 	ios->offset = 0;
 	ios->kern_buff = fscb;
-	ios->cred = sbi->s_cred;
 
-	ret = exofs_sbi_write(ios);
+	ret = ore_write(ios);
 	if (unlikely(ret))
-		EXOFS_ERR("%s: exofs_sbi_write failed.\n", __func__);
+		EXOFS_ERR("%s: ore_write failed.\n", __func__);
 	else
 		sb->s_dirt = 0;
 
@@ -360,7 +407,7 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 	unlock_super(sb);
 out:
 	EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	kfree(fscb);
 	return ret;
 }
@@ -384,15 +431,17 @@ static void _exofs_print_device(const char *msg, const char *dev_path,
 
 void exofs_free_sbi(struct exofs_sb_info *sbi)
 {
-	while (sbi->layout.s_numdevs) {
-		int i = --sbi->layout.s_numdevs;
-		struct osd_dev *od = sbi->layout.s_ods[i];
+	while (sbi->comps.numdevs) {
+		int i = --sbi->comps.numdevs;
+		struct osd_dev *od = sbi->comps.ods[i];
 
 		if (od) {
-			sbi->layout.s_ods[i] = NULL;
+			sbi->comps.ods[i] = NULL;
 			osduld_put_device(od);
 		}
 	}
+	if (sbi->comps.ods != sbi->_min_one_dev)
+		kfree(sbi->comps.ods);
 	kfree(sbi);
 }
 
@@ -419,8 +468,8 @@ static void exofs_put_super(struct super_block *sb)
 				  msecs_to_jiffies(100));
 	}
 
-	_exofs_print_device("Unmounting", NULL, sbi->layout.s_ods[0],
-			    sbi->layout.s_pid);
+	_exofs_print_device("Unmounting", NULL, sbi->comps.ods[0],
+			    sbi->one_comp.obj.partition);
 
 	bdi_destroy(&sbi->bdi);
 	exofs_free_sbi(sbi);
@@ -501,10 +550,19 @@ static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 		return -EINVAL;
 	}
 
+	EXOFS_DBGMSG("exofs: layout: "
+		"num_comps=%u stripe_unit=0x%x group_width=%u "
+		"group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
+		numdevs,
+		sbi->layout.stripe_unit,
+		sbi->layout.group_width,
+		_LLU(sbi->layout.group_depth),
+		sbi->layout.mirrors_p1,
+		sbi->data_map.odm_raid_algorithm);
 	return 0;
 }
 
-static unsigned __ra_pages(struct exofs_layout *layout)
+static unsigned __ra_pages(struct ore_layout *layout)
 {
 	const unsigned _MIN_RA = 32; /* min 128K read-ahead */
 	unsigned ra_pages = layout->group_width * layout->stripe_unit /
@@ -547,13 +605,11 @@ static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 	return !(odi->systemid_len || odi->osdname_len);
 }
 
-static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
+static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
+				       struct osd_dev *fscb_od,
 				       unsigned table_count)
 {
-	struct exofs_sb_info *sbi = *psbi;
-	struct osd_dev *fscb_od;
-	struct osd_obj_id obj = {.partition = sbi->layout.s_pid,
-				 .id = EXOFS_DEVTABLE_ID};
+	struct ore_comp comp;
 	struct exofs_device_table *dt;
 	unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 					     sizeof(*dt);
@@ -567,10 +623,14 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 		return -ENOMEM;
 	}
 
-	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);
+	sbi->comps.numdevs = 0;
+
+	comp.obj.partition = sbi->one_comp.obj.partition;
+	comp.obj.id = EXOFS_DEVTABLE_ID;
+	exofs_make_credential(comp.cred, &comp.obj);
+
+	ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
+			      table_bytes);
 	if (unlikely(ret)) {
 		EXOFS_ERR("ERROR: reading device table\n");
 		goto out;
@@ -588,16 +648,18 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 		goto out;
 
 	if (likely(numdevs > 1)) {
-		unsigned size = numdevs * sizeof(sbi->layout.s_ods[0]);
+		unsigned size = numdevs * sizeof(sbi->comps.ods[0]);
 
-		sbi = krealloc(sbi, sizeof(*sbi) + size, GFP_KERNEL);
-		if (unlikely(!sbi)) {
+		/* Twice bigger table: See exofs_init_comps() and below
+		 * comment
+		 */
+		sbi->comps.ods = kzalloc(size + size - 1, GFP_KERNEL);
+		if (unlikely(!sbi->comps.ods)) {
+			EXOFS_ERR("ERROR: faild allocating Device array[%d]\n",
+				  numdevs);
 			ret = -ENOMEM;
 			goto out;
 		}
-		memset(&sbi->layout.s_ods[1], 0,
-		       size - sizeof(sbi->layout.s_ods[0]));
-		*psbi = sbi;
 	}
 
 	for (i = 0; i < numdevs; i++) {
@@ -619,8 +681,8 @@ 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->layout.s_ods[i] = fscb_od;
-			++sbi->layout.s_numdevs;
+			sbi->comps.ods[i] = fscb_od;
+			++sbi->comps.numdevs;
 			fscb_od = NULL;
 			continue;
 		}
@@ -633,13 +695,13 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 			goto out;
 		}
 
-		sbi->layout.s_ods[i] = od;
-		++sbi->layout.s_numdevs;
+		sbi->comps.ods[i] = od;
+		++sbi->comps.numdevs;
 
 		/* Read the fscb of the other devices to make sure the FS
 		 * partition is there.
 		 */
-		ret = exofs_read_kern(od, sbi->s_cred, &obj, 0, &fscb,
+		ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
 				      sizeof(fscb));
 		if (unlikely(ret)) {
 			EXOFS_ERR("ERROR: Malformed participating device "
@@ -656,13 +718,22 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 
 out:
 	kfree(dt);
-	if (unlikely(!ret && fscb_od)) {
-		EXOFS_ERR(
-		      "ERROR: Bad device-table container device not present\n");
-		osduld_put_device(fscb_od);
-		ret = -EINVAL;
-	}
+	if (likely(!ret)) {
+		unsigned numdevs = sbi->comps.numdevs;
 
+		if (unlikely(fscb_od)) {
+			EXOFS_ERR("ERROR: Bad device-table container device not present\n");
+			osduld_put_device(fscb_od);
+			return -EINVAL;
+		}
+		/* exofs round-robins the device table view according to inode
+		 * number. We hold a: twice bigger table hence inodes can point
+		 * to any device and have a sequential view of the table
+		 * starting at this device. See exofs_init_comps()
+		 */
+		for (i = 0; i < numdevs - 1; ++i)
+			sbi->comps.ods[i + numdevs] = sbi->comps.ods[i];
+	}
 	return ret;
 }
 
@@ -676,7 +747,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 	struct exofs_sb_info *sbi;	/*extended info                  */
 	struct osd_dev *od;		/* Master device                 */
 	struct exofs_fscb fscb;		/*on-disk superblock info        */
-	struct osd_obj_id obj;
+	struct ore_comp comp;
 	unsigned table_count;
 	int ret;
 
@@ -684,10 +755,6 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 	if (!sbi)
 		return -ENOMEM;
 
-	ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
-	if (ret)
-		goto free_bdi;
-
 	/* use mount options to fill superblock */
 	if (opts->is_osdname) {
 		struct osd_dev_info odi = {.systemid_len = 0};
@@ -695,6 +762,8 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 		odi.osdname_len = strlen(opts->dev_name);
 		odi.osdname = (u8 *)opts->dev_name;
 		od = osduld_info_lookup(&odi);
+		kfree(opts->dev_name);
+		opts->dev_name = NULL;
 	} else {
 		od = osduld_path_lookup(opts->dev_name);
 	}
@@ -709,11 +778,16 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 	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;
 
+	sbi->one_comp.obj.partition = opts->pid;
+	sbi->one_comp.obj.id = 0;
+	exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
+	sbi->comps.numdevs = 1;
+	sbi->comps.single_comp = EC_SINGLE_COMP;
+	sbi->comps.comps = &sbi->one_comp;
+	sbi->comps.ods = sbi->_min_one_dev;
+
 	/* fill in some other data by hand */
 	memset(sb->s_id, 0, sizeof(sb->s_id));
 	strcpy(sb->s_id, "exofs");
@@ -724,11 +798,11 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_bdev = NULL;
 	sb->s_dev = 0;
 
-	obj.partition = sbi->layout.s_pid;
-	obj.id = EXOFS_SUPER_ID;
-	exofs_make_credential(sbi->s_cred, &obj);
+	comp.obj.partition = sbi->one_comp.obj.partition;
+	comp.obj.id = EXOFS_SUPER_ID;
+	exofs_make_credential(comp.cred, &comp.obj);
 
-	ret = exofs_read_kern(od, sbi->s_cred, &obj, 0, &fscb, sizeof(fscb));
+	ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
 	if (unlikely(ret))
 		goto free_sbi;
 
@@ -757,9 +831,11 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 
 	table_count = le64_to_cpu(fscb.s_dev_table_count);
 	if (table_count) {
-		ret = exofs_read_lookup_dev_table(&sbi, table_count);
+		ret = exofs_read_lookup_dev_table(sbi, od, table_count);
 		if (unlikely(ret))
 			goto free_sbi;
+	} else {
+		sbi->comps.ods[0] = od;
 	}
 
 	__sbi_read_stats(sbi);
@@ -793,20 +869,20 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 		goto free_sbi;
 	}
 
-	_exofs_print_device("Mounting", opts->dev_name, sbi->layout.s_ods[0],
-			    sbi->layout.s_pid);
-	if (opts->is_osdname)
-		kfree(opts->dev_name);
+	ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
+	if (ret) {
+		EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
+		goto free_sbi;
+	}
+
+	_exofs_print_device("Mounting", opts->dev_name, sbi->comps.ods[0],
+			    sbi->one_comp.obj.partition);
 	return 0;
 
 free_sbi:
-	bdi_destroy(&sbi->bdi);
-free_bdi:
 	EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
-		  opts->dev_name, sbi->layout.s_pid, ret);
+		  opts->dev_name, sbi->one_comp.obj.partition, ret);
 	exofs_free_sbi(sbi);
-	if (opts->is_osdname)
-		kfree(opts->dev_name);
 	return ret;
 }
 
@@ -837,7 +913,7 @@ static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
 	struct super_block *sb = dentry->d_sb;
 	struct exofs_sb_info *sbi = sb->s_fs_info;
-	struct exofs_io_state *ios;
+	struct ore_io_state *ios;
 	struct osd_attr attrs[] = {
 		ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 			OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
@@ -846,21 +922,18 @@ static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	};
 	uint64_t capacity = ULLONG_MAX;
 	uint64_t used = ULLONG_MAX;
-	uint8_t cred_a[OSD_CAP_LEN];
 	int ret;
 
-	ret = exofs_get_io_state(&sbi->layout, &ios);
+	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 	if (ret) {
-		EXOFS_DBGMSG("exofs_get_io_state failed.\n");
+		EXOFS_DBGMSG("ore_get_io_state failed.\n");
 		return ret;
 	}
 
-	exofs_make_credential(cred_a, &ios->obj);
-	ios->cred = sbi->s_cred;
 	ios->in_attr = attrs;
 	ios->in_attr_len = ARRAY_SIZE(attrs);
 
-	ret = exofs_sbi_read(ios);
+	ret = ore_read(ios);
 	if (unlikely(ret))
 		goto out;
 
@@ -889,7 +962,7 @@ static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_namelen = EXOFS_NAME_LEN;
 
 out:
-	exofs_put_io_state(ios);
+	ore_put_io_state(ios);
 	return ret;
 }