pnfs: clean up filelayout_alloc_commit_info

Remove unneeded else statement and clean up how commit info
dataserver buckets are replaced.

Suggested-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 26 insertions, 20 deletions

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 9319427e43e3..9cea9358fe52 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -850,11 +850,15 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 {
         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
         struct pnfs_commit_bucket *buckets;
-        int size;
+        int size, i;
 
         if (fl->commit_through_mds)
                 return 0;
-        if (cinfo->ds->nbuckets != 0) {
+
+        size = (fl->stripe_type == STRIPE_SPARSE) ?
+                fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
+
+        if (cinfo->ds->nbuckets >= size) {
                 /* 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
@@ -864,30 +868,32 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
                 return 0;
         }
 
-        size = (fl->stripe_type == STRIPE_SPARSE) ?
-                fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
-
         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
                           gfp_flags);
         if (!buckets)
                 return -ENOMEM;
-        else {
-                int i;
+        for (i = 0; i < size; i++) {
+                INIT_LIST_HEAD(&buckets[i].written);
+                INIT_LIST_HEAD(&buckets[i].committing);
+        }
 
-                spin_lock(cinfo->lock);
-                if (cinfo->ds->nbuckets != 0)
-                        kfree(buckets);
-                else {
-                        cinfo->ds->buckets = buckets;
-                        cinfo->ds->nbuckets = size;
-                        for (i = 0; i < size; i++) {
-                                INIT_LIST_HEAD(&buckets[i].written);
-                                INIT_LIST_HEAD(&buckets[i].committing);
-                        }
-                }
-                spin_unlock(cinfo->lock);
-                return 0;
+        spin_lock(cinfo->lock);
+        if (cinfo->ds->nbuckets >= size)
+                goto out;
+        for (i = 0; i < cinfo->ds->nbuckets; i++) {
+                list_splice(&cinfo->ds->buckets[i].written,
+                            &buckets[i].written);
+                list_splice(&cinfo->ds->buckets[i].committing,
+                            &buckets[i].committing);
+                buckets[i].wlseg = cinfo->ds->buckets[i].wlseg;
+                buckets[i].clseg = cinfo->ds->buckets[i].clseg;
         }
+        swap(cinfo->ds->buckets, buckets);
+        cinfo->ds->nbuckets = size;
+out:
+        spin_unlock(cinfo->lock);
+        kfree(buckets);
+        return 0;
 }
 
 static struct pnfs_layout_segment *