nfs: mark nfs_page reqs with flag for extra ref

Change the use of PG_INODE_REF - set it when taking extra reference on
subrequests and take care to only release once for each request.

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

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index b6ee3a6ee96dd2b06df61a022fadc0841da8d0b4..7368b2130a412cc6ab40b2e17af952ef354383ef 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -251,8 +251,10 @@ nfs_page_group_init(struct nfs_page *req, struct nfs_page *prev)
                /* grab extra ref if head request has extra ref from
                 * the write/commit path to handle handoff between write
                 * and commit lists */
-               if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags))
+               if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags)) {
+                       set_bit(PG_INODE_REF, &req->wb_flags);
                        kref_get(&req->wb_kref);
+               }
        }
 }
 

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 98ff061ccaf3650c6069b251e879a5537d6a8d7f..8e5745a4deff9444f2ca4d85c905c7757f54c134 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -448,7 +448,9 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
                set_page_private(req->wb_page, (unsigned long)req);
        }
        nfsi->npages++;
-       set_bit(PG_INODE_REF, &req->wb_flags);
+       /* this a head request for a page group - mark it as having an
+        * extra reference so sub groups can follow suit */
+       WARN_ON(test_and_set_bit(PG_INODE_REF, &req->wb_flags));
        kref_get(&req->wb_kref);
        spin_unlock(&inode->i_lock);
 }
@@ -474,7 +476,9 @@ static void nfs_inode_remove_request(struct nfs_page *req)
                nfsi->npages--;
                spin_unlock(&inode->i_lock);
        }
-       nfs_release_request(req);
+
+       if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags))
+               nfs_release_request(req);
 }
 
 static void