1 files changed, 22 insertions, 15 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 460d440310f2..f37f25c931f5 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -855,6 +855,7 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
                                   struct ocfs2_super *osb, loff_t pos,
                                   unsigned len, struct buffer_head *di_bh)
 {
+        u32 cend;
         struct ocfs2_write_ctxt *wc;
 
         wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS);
@@ -862,7 +863,8 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
                 return -ENOMEM;
 
         wc->w_cpos = pos >> osb->s_clustersize_bits;
-        wc->w_clen = ocfs2_clusters_for_bytes(osb->sb, len);
+        cend = (pos + len - 1) >> osb->s_clustersize_bits;
+        wc->w_clen = cend - wc->w_cpos + 1;
         get_bh(di_bh);
         wc->w_di_bh = di_bh;
 
@@ -928,18 +930,11 @@ static void ocfs2_write_failure(struct inode *inode,
                                 loff_t user_pos, unsigned user_len)
 {
         int i;
-        unsigned from, to;
+        unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
+                to = user_pos + user_len;
         struct page *tmppage;
 
-        ocfs2_zero_new_buffers(wc->w_target_page, user_pos, user_len);
-
-        if (wc->w_large_pages) {
-                from = wc->w_target_from;
-                to = wc->w_target_to;
-        } else {
-                from = 0;
-                to = PAGE_CACHE_SIZE;
-        }
+        ocfs2_zero_new_buffers(wc->w_target_page, from, to);
 
         for(i = 0; i < wc->w_num_pages; i++) {
                 tmppage = wc->w_pages[i];
@@ -989,9 +984,6 @@ static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
                         map_from = cluster_start;
                         map_to = cluster_end;
                 }
-
-                wc->w_target_from = map_from;
-                wc->w_target_to = map_to;
         } else {
                 /*
                  * If we haven't allocated the new page yet, we
@@ -1209,18 +1201,33 @@ static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
                                        loff_t pos, unsigned len)
 {
         int ret, i;
+        loff_t cluster_off;
+        unsigned int local_len = len;
         struct ocfs2_write_cluster_desc *desc;
+        struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb);
 
         for (i = 0; i < wc->w_clen; i++) {
                 desc = &wc->w_desc[i];
 
+                /*
+                 * We have to make sure that the total write passed in
+                 * doesn't extend past a single cluster.
+                 */
+                local_len = len;
+                cluster_off = pos & (osb->s_clustersize - 1);
+                if ((cluster_off + local_len) > osb->s_clustersize)
+                        local_len = osb->s_clustersize - cluster_off;
+
                 ret = ocfs2_write_cluster(mapping, desc->c_phys,
                                           desc->c_unwritten, data_ac, meta_ac,
-                                          wc, desc->c_cpos, pos, len);
+                                          wc, desc->c_cpos, pos, local_len);
                 if (ret) {
                         mlog_errno(ret);
                         goto out;
                 }
+
+                len -= local_len;
+                pos += local_len;
         }
 
         ret = 0;