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>

1 files changed, 76 insertions, 32 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 510bf84c9cf5..077583b50391 100644
--- 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)