1 files changed, 81 insertions, 12 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index dbc89fa7e9d5..310fdeca6250 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -80,6 +80,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context*,
 static int nfs_wait_on_write_congestion(struct address_space *, int);
 static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int);
 static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how);
+static int nfs_wb_page_priority(struct inode *inode, struct page *page, int how);
 static const struct rpc_call_ops nfs_write_partial_ops;
 static const struct rpc_call_ops nfs_write_full_ops;
 static const struct rpc_call_ops nfs_commit_ops;
@@ -1476,29 +1477,38 @@ int nfs_commit_inode(struct inode *inode, int how)
 }
 #endif
 
-long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
-                unsigned int npages, int how)
+long nfs_sync_mapping_wait(struct address_space *mapping, struct writeback_control *wbc, int how)
 {
+        struct inode *inode = mapping->host;
         struct nfs_inode *nfsi = NFS_I(inode);
-        struct address_space *mapping = inode->i_mapping;
-        struct writeback_control wbc = {
-                .bdi = mapping->backing_dev_info,
-                .sync_mode = WB_SYNC_ALL,
-                .nr_to_write = LONG_MAX,
-                .range_start = ((loff_t)idx_start) << PAGE_CACHE_SHIFT,
-                .range_end = ((loff_t)(idx_start + npages - 1)) << PAGE_CACHE_SHIFT,
-        };
+        unsigned long idx_start, idx_end;
+        unsigned int npages = 0;
         LIST_HEAD(head);
         int nocommit = how & FLUSH_NOCOMMIT;
         long pages, ret;
 
+        /* FIXME */
+        if (wbc->range_cyclic)
+                idx_start = 0;
+        else {
+                idx_start = wbc->range_start >> PAGE_CACHE_SHIFT;
+                idx_end = wbc->range_end >> PAGE_CACHE_SHIFT;
+                if (idx_end > idx_start) {
+                        unsigned long l_npages = 1 + idx_end - idx_start;
+                        npages = l_npages;
+                        if (sizeof(npages) != sizeof(l_npages) &&
+                                        (unsigned long)npages != l_npages)
+                                npages = 0;
+                }
+        }
         how &= ~FLUSH_NOCOMMIT;
         spin_lock(&nfsi->req_lock);
         do {
+                wbc->pages_skipped = 0;
                 ret = nfs_wait_on_requests_locked(inode, idx_start, npages);
                 if (ret != 0)
                         continue;
-                pages = nfs_scan_dirty(mapping, &wbc, &head);
+                pages = nfs_scan_dirty(mapping, wbc, &head);
                 if (pages != 0) {
                         spin_unlock(&nfsi->req_lock);
                         if (how & FLUSH_INVALIDATE) {
@@ -1509,11 +1519,16 @@ long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
                         spin_lock(&nfsi->req_lock);
                         continue;
                 }
+                if (wbc->pages_skipped != 0)
+                        continue;
                 if (nocommit)
                         break;
                 pages = nfs_scan_commit(inode, &head, idx_start, npages);
-                if (pages == 0)
+                if (pages == 0) {
+                        if (wbc->pages_skipped != 0)
+                                continue;
                         break;
+                }
                 if (how & FLUSH_INVALIDATE) {
                         spin_unlock(&nfsi->req_lock);
                         nfs_cancel_commit_list(&head);
@@ -1530,6 +1545,60 @@ long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
         return ret;
 }
 
+/*
+ * flush the inode to disk.
+ */
+int nfs_wb_all(struct inode *inode)
+{
+        struct address_space *mapping = inode->i_mapping;
+        struct writeback_control wbc = {
+                .bdi = mapping->backing_dev_info,
+                .sync_mode = WB_SYNC_ALL,
+                .nr_to_write = LONG_MAX,
+                .range_cyclic = 1,
+        };
+        int ret;
+
+        ret = nfs_sync_mapping_wait(mapping, &wbc, 0);
+        if (ret >= 0)
+                return 0;
+        return ret;
+}
+
+int nfs_sync_mapping_range(struct address_space *mapping, loff_t range_start, loff_t range_end, int how)
+{
+        struct writeback_control wbc = {
+                .bdi = mapping->backing_dev_info,
+                .sync_mode = WB_SYNC_ALL,
+                .nr_to_write = LONG_MAX,
+                .range_start = range_start,
+                .range_end = range_end,
+        };
+        int ret;
+
+        ret = nfs_sync_mapping_wait(mapping, &wbc, how);
+        if (ret >= 0)
+                return 0;
+        return ret;
+}
+
+static int nfs_wb_page_priority(struct inode *inode, struct page *page, int how)
+{
+        loff_t range_start = page_offset(page);
+        loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
+
+        return nfs_sync_mapping_range(inode->i_mapping, range_start, range_end, how | FLUSH_STABLE);
+}
+
+/*
+ * Write back all requests on one page - we do this before reading it.
+ */
+int nfs_wb_page(struct inode *inode, struct page* page)
+{
+        return nfs_wb_page_priority(inode, page, 0);
+}
+
+
 int __init nfs_init_writepagecache(void)
 {
         nfs_wdata_cachep = kmem_cache_create("nfs_write_data",