pnfs-obj: osd raid engine read/write implementation
With the use of the in-kernel osd library. Implement read/write
of data from/to osd-objects according to information specified
in the objects-layout.
Support for stripping over mirrors with a received stripe_unit.
There are however a few constrains which are not supported:
1. Stripe Unit must be a multiple of PAGE_SIZE
2. stripe length (stripe_unit * number_of_stripes) can not be
bigger then 32bit.
Also support raid-groups and partial-layout. Partial-layout is
when not all the groups are received on the line, addressing
only a partial range of the file.
TODO:
Only raid0! raid 4/5/6 support will come at later stage
A none supported layout will send IO through the MDS
[Important fallout from the last rebase]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
[gfp_flags]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
diff --git a/fs/nfs/objlayout/objlayout.h b/fs/nfs/objlayout/objlayout.h
index fa02621..9a405e8 100644
--- a/fs/nfs/objlayout/objlayout.h
+++ b/fs/nfs/objlayout/objlayout.h
@@ -59,6 +59,26 @@
}
/*
+ * per-I/O operation state
+ * embedded in objects provider io_state data structure
+ */
+struct objlayout_io_state {
+ struct pnfs_layout_segment *lseg;
+
+ struct page **pages;
+ unsigned pgbase;
+ unsigned nr_pages;
+ unsigned long count;
+ loff_t offset;
+ bool sync;
+
+ void *rpcdata;
+ int status; /* res */
+ int eof; /* res */
+ int committed; /* res */
+};
+
+/*
* Raid engine I/O API
*/
extern int objio_alloc_lseg(struct pnfs_layout_segment **outp,
@@ -68,9 +88,24 @@
gfp_t gfp_flags);
extern void objio_free_lseg(struct pnfs_layout_segment *lseg);
+extern int objio_alloc_io_state(
+ struct pnfs_layout_segment *lseg,
+ struct objlayout_io_state **outp,
+ gfp_t gfp_flags);
+extern void objio_free_io_state(struct objlayout_io_state *state);
+
+extern ssize_t objio_read_pagelist(struct objlayout_io_state *ol_state);
+extern ssize_t objio_write_pagelist(struct objlayout_io_state *ol_state,
+ bool stable);
+
/*
* callback API
*/
+extern void objlayout_read_done(struct objlayout_io_state *state,
+ ssize_t status, bool sync);
+extern void objlayout_write_done(struct objlayout_io_state *state,
+ ssize_t status, bool sync);
+
extern int objlayout_get_deviceinfo(struct pnfs_layout_hdr *pnfslay,
struct nfs4_deviceid *d_id, struct pnfs_osd_deviceaddr **deviceaddr,
gfp_t gfp_flags);
@@ -89,4 +124,11 @@
gfp_t gfp_flags);
extern void objlayout_free_lseg(struct pnfs_layout_segment *);
+extern enum pnfs_try_status objlayout_read_pagelist(
+ struct nfs_read_data *);
+
+extern enum pnfs_try_status objlayout_write_pagelist(
+ struct nfs_write_data *,
+ int how);
+
#endif /* _OBJLAYOUT_H */