NFSv4.1: alloc and free commit_buckets

Create a preallocated list header to hold nfs_pages for each
non-MDS COMMIT destination.  Note this is not necessarily each DS,
but is basically each <DS, fh> pair.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 24 insertions, 0 deletions

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 9401afd5650e..03ff80c67c6e 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -503,6 +503,7 @@ filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 
         dprintk("--> %s\n", __func__);
         nfs4_fl_put_deviceid(fl->dsaddr);
+        kfree(fl->commit_buckets);
         _filelayout_free_lseg(fl);
 }
 
@@ -524,6 +525,27 @@ filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
                 _filelayout_free_lseg(fl);
                 return NULL;
         }
+
+        /* This assumes there is only one IOMODE_RW lseg.  What
+         * we really want to do is have a layout_hdr level
+         * dictionary of <multipath_list4, fh> keys, each
+         * associated with a struct list_head, populated by calls
+         * to filelayout_write_pagelist().
+         * */
+        if ((!fl->commit_through_mds) && (lgr->range.iomode == IOMODE_RW)) {
+                int i;
+                int size = (fl->stripe_type == STRIPE_SPARSE) ?
+                        fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
+
+                fl->commit_buckets = kcalloc(size, sizeof(struct list_head), GFP_KERNEL);
+                if (!fl->commit_buckets) {
+                        filelayout_free_lseg(&fl->generic_hdr);
+                        return NULL;
+                }
+                fl->number_of_buckets = size;
+                for (i = 0; i < size; i++)
+                        INIT_LIST_HEAD(&fl->commit_buckets[i]);
+        }
         return &fl->generic_hdr;
 }
 
diff --git a/fs/nfs/nfs4filelayout.h b/fs/nfs/nfs4filelayout.h
index ee0c907742b5..085a354e0f08 100644
--- a/fs/nfs/nfs4filelayout.h
+++ b/fs/nfs/nfs4filelayout.h
@@ -79,6 +79,8 @@ struct nfs4_filelayout_segment {
         struct nfs4_file_layout_dsaddr *dsaddr; /* Point to GETDEVINFO data */
         unsigned int num_fh;
         struct nfs_fh **fh_array;
+        struct list_head *commit_buckets; /* Sort commits to ds */
+        int number_of_buckets;
 };
 
 static inline struct nfs4_filelayout_segment *