pnfs-obj: report errors and .encode_layoutreturn Implementation.
An io_state pre-allocates an error information structure for each
possible osd-device that might error during IO. When IO is done if all
was well the io_state is freed. (as today). If the I/O has ended with an
error, the io_state is queued on a per-layout err_list. When eventually
encode_layoutreturn() is called, each error is properly encoded on the
XDR buffer and only then the io_state is removed from err_list and
de-allocated.
It is up to the io_engine to fill in the segment that fault and the type
of osd_error that occurred. By calling objlayout_io_set_result() for
each failing device.
In objio_osd:
* Allocate io-error descriptors space as part of io_state
* Use generic objlayout error reporting at end of io.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
diff --git a/fs/nfs/objlayout/objlayout.h b/fs/nfs/objlayout/objlayout.h
index 9a405e8..b0bb975 100644
--- a/fs/nfs/objlayout/objlayout.h
+++ b/fs/nfs/objlayout/objlayout.h
@@ -50,6 +50,10 @@
*/
struct objlayout {
struct pnfs_layout_hdr pnfs_layout;
+
+ /* for layout_return */
+ spinlock_t lock;
+ struct list_head err_list;
};
static inline struct objlayout *
@@ -76,6 +80,16 @@
int status; /* res */
int eof; /* res */
int committed; /* res */
+
+ /* Error reporting (layout_return) */
+ struct list_head err_list;
+ unsigned num_comps;
+ /* Pointer to array of error descriptors of size num_comps.
+ * It should contain as many entries as devices in the osd_layout
+ * that participate in the I/O. It is up to the io_engine to allocate
+ * needed space and set num_comps.
+ */
+ struct pnfs_osd_ioerr *ioerrs;
};
/*
@@ -101,6 +115,10 @@
/*
* callback API
*/
+extern void objlayout_io_set_result(struct objlayout_io_state *state,
+ unsigned index, struct pnfs_osd_objid *pooid,
+ int osd_error, u64 offset, u64 length, bool is_write);
+
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,
@@ -131,4 +149,9 @@
struct nfs_write_data *,
int how);
+extern void objlayout_encode_layoutreturn(
+ struct pnfs_layout_hdr *,
+ struct xdr_stream *,
+ const struct nfs4_layoutreturn_args *);
+
#endif /* _OBJLAYOUT_H */