pnfs: Fix the check for requests in range of layout segment

[karo-tx-linux.git] / fs / nfs / pnfs.c

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index adc6ec28d4b59d3181c76ca8f33a9fed25d68ce9..c383d0913b54c90fb96020a62faaf989a5d946b3 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2094,12 +2094,26 @@ pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio)
 }
 EXPORT_SYMBOL_GPL(pnfs_generic_pg_check_layout);
 
+/*
+ * Check for any intersection between the request and the pgio->pg_lseg,
+ * and if none, put this pgio->pg_lseg away.
+ */
+static void
+pnfs_generic_pg_check_range(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+       if (pgio->pg_lseg && !pnfs_lseg_request_intersecting(pgio->pg_lseg, req)) {
+               pnfs_put_lseg(pgio->pg_lseg);
+               pgio->pg_lseg = NULL;
+       }
+}
+
 void
 pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
 {
        u64 rd_size = req->wb_bytes;
 
        pnfs_generic_pg_check_layout(pgio);
+       pnfs_generic_pg_check_range(pgio, req);
        if (pgio->pg_lseg == NULL) {
                if (pgio->pg_dreq == NULL)
                        rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
@@ -2131,6 +2145,7 @@ pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
                           struct nfs_page *req, u64 wb_size)
 {
        pnfs_generic_pg_check_layout(pgio);
+       pnfs_generic_pg_check_range(pgio, req);
        if (pgio->pg_lseg == NULL) {
                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
                                                   req->wb_context,
@@ -2191,16 +2206,10 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
                seg_end = pnfs_end_offset(pgio->pg_lseg->pls_range.offset,
                                     pgio->pg_lseg->pls_range.length);
                req_start = req_offset(req);
-               WARN_ON_ONCE(req_start >= seg_end);
+
                /* start of request is past the last byte of this segment */
-               if (req_start >= seg_end) {
-                       /* reference the new lseg */
-                       if (pgio->pg_ops->pg_cleanup)
-                               pgio->pg_ops->pg_cleanup(pgio);
-                       if (pgio->pg_ops->pg_init)
-                               pgio->pg_ops->pg_init(pgio, req);
+               if (req_start >= seg_end)
                        return 0;
-               }
 
                /* adjust 'size' iff there are fewer bytes left in the
                 * segment than what nfs_generic_pg_test returned */