ocfs2: small cleanup of ocfs2_write_begin_nolock()

We can easily seperate out the write descriptor setup and manipulation
into helper functions.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 510bf84..077583b 100644 (file)
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -1188,6 +1188,31 @@ out:
        return ret;
 }
 
+static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
+                                      struct ocfs2_alloc_context *data_ac,
+                                      struct ocfs2_alloc_context *meta_ac,
+                                      struct ocfs2_write_ctxt *wc,
+                                      loff_t pos, unsigned len)
+{
+       int ret, i;
+       struct ocfs2_write_cluster_desc *desc;
+
+       for (i = 0; i < wc->w_clen; i++) {
+               desc = &wc->w_desc[i];
+
+               ret = ocfs2_write_cluster(mapping, desc->c_phys, data_ac,
+                                         meta_ac, wc, desc->c_cpos, pos, len);
+               if (ret) {
+                       mlog_errno(ret);
+                       goto out;
+               }
+       }
+
+       ret = 0;
+out:
+       return ret;
+}
+
 /*
  * ocfs2_write_end() wants to know which parts of the target page it
  * should complete the write on. It's easiest to compute them ahead of
@@ -1240,30 +1265,19 @@ static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
        }
 }
 
-int ocfs2_write_begin_nolock(struct address_space *mapping,
-                            loff_t pos, unsigned len, unsigned flags,
-                            struct page **pagep, void **fsdata,
-                            struct buffer_head *di_bh, struct page *mmap_page)
+/*
+ * Populate each single-cluster write descriptor in the write context
+ * with information about the i/o to be done.
+ */
+static int ocfs2_populate_write_desc(struct inode *inode,
+                                    struct ocfs2_write_ctxt *wc,
+                                    unsigned int *clusters_to_alloc)
 {
-       int ret, i, credits = OCFS2_INODE_UPDATE_CREDITS;
-       unsigned int num_clusters = 0, clusters_to_alloc = 0;
-       u32 phys = 0;
-       struct ocfs2_write_ctxt *wc;
-       struct inode *inode = mapping->host;
-       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
-       struct ocfs2_dinode *di;
-       struct ocfs2_alloc_context *data_ac = NULL;
-       struct ocfs2_alloc_context *meta_ac = NULL;
-       handle_t *handle;
+       int ret;
        struct ocfs2_write_cluster_desc *desc;
-
-       ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
-       if (ret) {
-               mlog_errno(ret);
-               return ret;
-       }
-
-       di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+       unsigned int num_clusters = 0;
+       u32 phys = 0;
+       int i;
 
        for (i = 0; i < wc->w_clen; i++) {
                desc = &wc->w_desc[i];
@@ -1287,12 +1301,46 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
                desc->c_phys = phys;
                if (phys == 0) {
                        desc->c_new = 1;
-                       clusters_to_alloc++;
+                       *clusters_to_alloc = *clusters_to_alloc + 1;
                }
 
                num_clusters--;
        }
 
+       ret = 0;
+out:
+       return ret;
+}
+
+int ocfs2_write_begin_nolock(struct address_space *mapping,
+                            loff_t pos, unsigned len, unsigned flags,
+                            struct page **pagep, void **fsdata,
+                            struct buffer_head *di_bh, struct page *mmap_page)
+{
+       int ret, credits = OCFS2_INODE_UPDATE_CREDITS;
+       unsigned int clusters_to_alloc = 0;
+       struct ocfs2_write_ctxt *wc;
+       struct inode *inode = mapping->host;
+       struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+       struct ocfs2_dinode *di;
+       struct ocfs2_alloc_context *data_ac = NULL;
+       struct ocfs2_alloc_context *meta_ac = NULL;
+       handle_t *handle;
+
+       ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
+       if (ret) {
+               mlog_errno(ret);
+               return ret;
+       }
+
+       ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc);
+       if (ret) {
+               mlog_errno(ret);
+               goto out;
+       }
+
+       di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
+
        /*
         * We set w_target_from, w_target_to here so that
         * ocfs2_write_end() knows which range in the target page to
@@ -1351,15 +1399,11 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
                goto out_commit;
        }
 
-       for (i = 0; i < wc->w_clen; i++) {
-               desc = &wc->w_desc[i];
-
-               ret = ocfs2_write_cluster(mapping, desc->c_phys, data_ac,
-                                         meta_ac, wc, desc->c_cpos, pos, len);
-               if (ret) {
-                       mlog_errno(ret);
-                       goto out_commit;
-               }
+       ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos,
+                                         len);
+       if (ret) {
+               mlog_errno(ret);
+               goto out_commit;
        }
 
        if (data_ac)