pnfs-obj: objlayout_encode_layoutcommit implementation

* Define API for io-engines to report delta_space_used in IOs
* Encode the osd-layout specific information of the layoutcommit
  XDR buffer.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

3 files changed, 61 insertions, 0 deletions

diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
index 8bca5e13f3ef..3be124160e97 100644
--- a/fs/nfs/objlayout/objio_osd.c
+++ b/fs/nfs/objlayout/objio_osd.c
@@ -1018,6 +1018,7 @@ static struct pnfs_layoutdriver_type objlayout_type = {
 
         .free_deviceid_node      = objio_free_deviceid_node,
 
+        .encode_layoutcommit     = objlayout_encode_layoutcommit,
         .encode_layoutreturn     = objlayout_encode_layoutreturn,
 };
 
diff --git a/fs/nfs/objlayout/objlayout.c b/fs/nfs/objlayout/objlayout.c
index f7caecff6b4d..dc3956c0de80 100644
--- a/fs/nfs/objlayout/objlayout.c
+++ b/fs/nfs/objlayout/objlayout.c
@@ -225,6 +225,7 @@ objlayout_iodone(struct objlayout_io_state *state)
                 struct objlayout *objlay = OBJLAYOUT(state->lseg->pls_layout);
 
                 spin_lock(&objlay->lock);
+                objlay->delta_space_valid = OBJ_DSU_INVALID;
                 list_add(&objlay->err_list, &state->err_list);
                 spin_unlock(&objlay->lock);
         }
@@ -433,6 +434,35 @@ objlayout_write_pagelist(struct nfs_write_data *wdata,
         return PNFS_ATTEMPTED;
 }
 
+void
+objlayout_encode_layoutcommit(struct pnfs_layout_hdr *pnfslay,
+                              struct xdr_stream *xdr,
+                              const struct nfs4_layoutcommit_args *args)
+{
+        struct objlayout *objlay = OBJLAYOUT(pnfslay);
+        struct pnfs_osd_layoutupdate lou;
+        __be32 *start;
+
+        dprintk("%s: Begin\n", __func__);
+
+        spin_lock(&objlay->lock);
+        lou.dsu_valid = (objlay->delta_space_valid == OBJ_DSU_VALID);
+        lou.dsu_delta = objlay->delta_space_used;
+        objlay->delta_space_used = 0;
+        objlay->delta_space_valid = OBJ_DSU_INIT;
+        lou.olu_ioerr_flag = !list_empty(&objlay->err_list);
+        spin_unlock(&objlay->lock);
+
+        start = xdr_reserve_space(xdr, 4);
+
+        BUG_ON(pnfs_osd_xdr_encode_layoutupdate(xdr, &lou));
+
+        *start = cpu_to_be32((xdr->p - start - 1) * 4);
+
+        dprintk("%s: Return delta_space_used %lld err %d\n", __func__,
+                lou.dsu_delta, lou.olu_ioerr_flag);
+}
+
 static int
 err_prio(u32 oer_errno)
 {
diff --git a/fs/nfs/objlayout/objlayout.h b/fs/nfs/objlayout/objlayout.h
index b0bb975058e4..a8244c8e042d 100644
--- a/fs/nfs/objlayout/objlayout.h
+++ b/fs/nfs/objlayout/objlayout.h
@@ -51,6 +51,14 @@
 struct objlayout {
         struct pnfs_layout_hdr pnfs_layout;
 
+         /* for layout_commit */
+        enum osd_delta_space_valid_enum {
+                OBJ_DSU_INIT = 0,
+                OBJ_DSU_VALID,
+                OBJ_DSU_INVALID,
+        } delta_space_valid;
+        s64 delta_space_used;  /* consumed by write ops */
+
          /* for layout_return */
         spinlock_t lock;
         struct list_head err_list;
@@ -119,6 +127,23 @@ 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);
 
+static inline void
+objlayout_add_delta_space_used(struct objlayout_io_state *state, s64 space_used)
+{
+        struct objlayout *objlay = OBJLAYOUT(state->lseg->pls_layout);
+
+        /* If one of the I/Os errored out and the delta_space_used was
+         * invalid we render the complete report as invalid. Protocol mandate
+         * the DSU be accurate or not reported.
+         */
+        spin_lock(&objlay->lock);
+        if (objlay->delta_space_valid != OBJ_DSU_INVALID) {
+                objlay->delta_space_valid = OBJ_DSU_VALID;
+                objlay->delta_space_used += space_used;
+        }
+        spin_unlock(&objlay->lock);
+}
+
 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,
@@ -149,6 +174,11 @@ extern enum pnfs_try_status objlayout_write_pagelist(
         struct nfs_write_data *,
         int how);
 
+extern void objlayout_encode_layoutcommit(
+        struct pnfs_layout_hdr *,
+        struct xdr_stream *,
+        const struct nfs4_layoutcommit_args *);
+
 extern void objlayout_encode_layoutreturn(
         struct pnfs_layout_hdr *,
         struct xdr_stream *,