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>
This commit is contained in:
Boaz Harrosh
2009-11-08 14:54:08 +02:00
parent 8ce9bdd1fb
commit 06886a5a3d
5 changed files with 646 additions and 352 deletions

View File

@@ -155,22 +155,4 @@ enum {
(((name_len) + offsetof(struct exofs_dir_entry, name) + \
EXOFS_DIR_ROUND) & ~EXOFS_DIR_ROUND)
/*************************
* function declarations *
*************************/
/* osd.c */
void exofs_make_credential(u8 cred_a[OSD_CAP_LEN],
const struct osd_obj_id *obj);
int exofs_check_ok_resid(struct osd_request *or, u64 *in_resid, u64 *out_resid);
static inline int exofs_check_ok(struct osd_request *or)
{
return exofs_check_ok_resid(or, NULL, NULL);
}
int exofs_sync_op(struct osd_request *or, int timeout, u8 *cred);
int exofs_async_op(struct osd_request *or,
osd_req_done_fn *async_done, void *caller_context, u8 *cred);
int extract_attr_from_req(struct osd_request *or, struct osd_attr *attr);
#endif /*ifndef __EXOFS_COM_H__*/