exofs: Move all operations to an io_engine
In anticipation for multi-device operations, we separate osd operations
into an abstract I/O API. Currently only one device is used but later
when adding more devices, we will drive all devices in parallel according
to a "data_map" that describes how data is arranged on multiple devices.
The file system level operates, like before, as if there is one object
(inode-number) and an i_size. The io engine will split this to the same
object-number but on multiple device.
At first we introduce Mirror (raid 1) layout. But at the final outcome
we intend to fully implement the pNFS-Objects data-map, including
raid 0,4,5,6 over mirrored devices, over multiple device-groups. And
more. See: http://tools.ietf.org/html/draft-ietf-nfsv4-pnfs-obj-12
* Define an io_state based API for accessing osd storage devices
in an abstract way.
Usage:
First a caller allocates an io state with:
exofs_get_io_state(struct exofs_sb_info *sbi,
struct exofs_io_state** ios);
Then calles one of:
exofs_sbi_create(struct exofs_io_state *ios);
exofs_sbi_remove(struct exofs_io_state *ios);
exofs_sbi_write(struct exofs_io_state *ios);
exofs_sbi_read(struct exofs_io_state *ios);
exofs_oi_truncate(struct exofs_i_info *oi, u64 new_len);
And when done
exofs_put_io_state(struct exofs_io_state *ios);
* Convert all source files to use this new API
* Convert from bio_alloc to bio_kmalloc
* In io engine we make use of the now fixed osd_req_decode_sense
There are no functional changes or on disk additions after this patch.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
index 5ec72e0..2e08859 100644
--- a/fs/exofs/exofs.h
+++ b/fs/exofs/exofs.h
@@ -30,14 +30,13 @@
* along with exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#ifndef __EXOFS_H__
+#define __EXOFS_H__
#include <linux/fs.h>
#include <linux/time.h>
#include "common.h"
-#ifndef __EXOFS_H__
-#define __EXOFS_H__
-
#define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
#ifdef CONFIG_EXOFS_DEBUG
@@ -56,6 +55,7 @@
*/
struct exofs_sb_info {
struct osd_dev *s_dev; /* returned by get_osd_dev */
+ 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 */
@@ -79,6 +79,50 @@
struct inode vfs_inode; /* normal in-memory inode */
};
+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_sb_info *sbi;
+ struct osd_obj_id obj;
+ u8 *cred;
+
+ /* Global read/write IO*/
+ loff_t offset;
+ unsigned long length;
+ void *kern_buff;
+ struct bio *bio;
+
+ /* 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;
+ } 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
*/
@@ -130,6 +174,42 @@
/*************************
* 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_sb_info *sbi, 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 */
void exofs_truncate(struct inode *inode);
int exofs_setattr(struct dentry *, struct iattr *);
@@ -169,6 +249,7 @@
/* 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;