1 files changed, 76 insertions, 123 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 0d7a77cc394b..e2bb66c34406 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -110,6 +110,13 @@ void nfs_writedata_release(void *wdata)
         nfs_writedata_free(wdata);
 }
 
+static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
+{
+        ctx->error = error;
+        smp_wmb();
+        set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
+}
+
 static struct nfs_page *nfs_page_find_request_locked(struct page *page)
 {
         struct nfs_page *req = NULL;
@@ -243,10 +250,7 @@ static void nfs_end_page_writeback(struct page *page)
 
 /*
  * Find an associated nfs write request, and prepare to flush it out
- * Returns 1 if there was no write request, or if the request was
- * already tagged by nfs_set_page_dirty.Returns 0 if the request
- * was not tagged.
- * May also return an error if the user signalled nfs_wait_on_request().
+ * May return an error if the user signalled nfs_wait_on_request().
  */
 static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
                                 struct page *page)
@@ -261,7 +265,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
                 req = nfs_page_find_request_locked(page);
                 if (req == NULL) {
                         spin_unlock(&inode->i_lock);
-                        return 1;
+                        return 0;
                 }
                 if (nfs_lock_request_dontget(req))
                         break;
@@ -282,7 +286,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
                 spin_unlock(&inode->i_lock);
                 nfs_unlock_request(req);
                 nfs_pageio_complete(pgio);
-                return 1;
+                return 0;
         }
         if (nfs_set_page_writeback(page) != 0) {
                 spin_unlock(&inode->i_lock);
@@ -290,70 +294,56 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
         }
         radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
                         NFS_PAGE_TAG_LOCKED);
-        ret = test_bit(PG_NEED_FLUSH, &req->wb_flags);
         spin_unlock(&inode->i_lock);
         nfs_pageio_add_request(pgio, req);
-        return ret;
+        return 0;
 }
 
-/*
- * Write an mmapped page to the server.
- */
-static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
+static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio)
 {
-        struct nfs_pageio_descriptor mypgio, *pgio;
-        struct nfs_open_context *ctx;
         struct inode *inode = page->mapping->host;
-        unsigned offset;
-        int err;
 
         nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
         nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
 
-        if (wbc->for_writepages)
-                pgio = wbc->fs_private;
-        else {
-                nfs_pageio_init_write(&mypgio, inode, wb_priority(wbc));
-                pgio = &mypgio;
-        }
-
         nfs_pageio_cond_complete(pgio, page->index);
+        return nfs_page_async_flush(pgio, page);
+}
 
-        err = nfs_page_async_flush(pgio, page);
-        if (err <= 0)
-                goto out;
-        err = 0;
-        offset = nfs_page_length(page);
-        if (!offset)
-                goto out;
-
-        nfs_pageio_cond_complete(pgio, page->index);
+/*
+ * Write an mmapped page to the server.
+ */
+static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
+{
+        struct nfs_pageio_descriptor pgio;
+        int err;
 
-        ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE);
-        if (ctx == NULL) {
-                err = -EBADF;
-                goto out;
-        }
-        err = nfs_writepage_setup(ctx, page, 0, offset);
-        put_nfs_open_context(ctx);
-        if (err != 0)
-                goto out;
-        err = nfs_page_async_flush(pgio, page);
-        if (err > 0)
-                err = 0;
-out:
-        if (!wbc->for_writepages)
-                nfs_pageio_complete(pgio);
-        return err;
+        nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc));
+        err = nfs_do_writepage(page, wbc, &pgio);
+        nfs_pageio_complete(&pgio);
+        if (err < 0)
+                return err;
+        if (pgio.pg_error < 0)
+                return pgio.pg_error;
+        return 0;
 }
 
 int nfs_writepage(struct page *page, struct writeback_control *wbc)
 {
-        int err;
+        int ret;
+
+        ret = nfs_writepage_locked(page, wbc);
+        unlock_page(page);
+        return ret;
+}
+
+static int nfs_writepages_callback(struct page *page, struct writeback_control *wbc, void *data)
+{
+        int ret;
 
-        err = nfs_writepage_locked(page, wbc);
+        ret = nfs_do_writepage(page, wbc, data);
         unlock_page(page);
-        return err; 
+        return ret;
 }
 
 int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
@@ -365,12 +355,11 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
         nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES);
 
         nfs_pageio_init_write(&pgio, inode, wb_priority(wbc));
-        wbc->fs_private = &pgio;
-        err = generic_writepages(mapping, wbc);
+        err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
         nfs_pageio_complete(&pgio);
-        if (err)
+        if (err < 0)
                 return err;
-        if (pgio.pg_error)
+        if (pgio.pg_error < 0)
                 return pgio.pg_error;
         return 0;
 }
@@ -389,14 +378,11 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
                 return error;
         if (!nfsi->npages) {
                 igrab(inode);
-                nfs_begin_data_update(inode);
                 if (nfs_have_delegation(inode, FMODE_WRITE))
                         nfsi->change_attr++;
         }
         SetPagePrivate(req->wb_page);
         set_page_private(req->wb_page, (unsigned long)req);
-        if (PageDirty(req->wb_page))
-                set_bit(PG_NEED_FLUSH, &req->wb_flags);
         nfsi->npages++;
         kref_get(&req->wb_kref);
         return 0;
@@ -416,12 +402,9 @@ static void nfs_inode_remove_request(struct nfs_page *req)
         set_page_private(req->wb_page, 0);
         ClearPagePrivate(req->wb_page);
         radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index);
-        if (test_and_clear_bit(PG_NEED_FLUSH, &req->wb_flags))
-                __set_page_dirty_nobuffers(req->wb_page);
         nfsi->npages--;
         if (!nfsi->npages) {
                 spin_unlock(&inode->i_lock);
-                nfs_end_data_update(inode);
                 iput(inode);
         } else
                 spin_unlock(&inode->i_lock);
@@ -682,7 +665,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
 
 int nfs_flush_incompatible(struct file *file, struct page *page)
 {
-        struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
+        struct nfs_open_context *ctx = nfs_file_open_context(file);
         struct nfs_page *req;
         int do_flush, status;
         /*
@@ -716,7 +699,7 @@ int nfs_flush_incompatible(struct file *file, struct page *page)
 int nfs_updatepage(struct file *file, struct page *page,
                 unsigned int offset, unsigned int count)
 {
-        struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
+        struct nfs_open_context *ctx = nfs_file_open_context(file);
         struct inode    *inode = page->mapping->host;
         int             status = 0;
 
@@ -967,7 +950,7 @@ static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata)
 
         if (task->tk_status < 0) {
                 nfs_set_pageerror(page);
-                req->wb_context->error = task->tk_status;
+                nfs_context_set_write_error(req->wb_context, task->tk_status);
                 dprintk(", error = %d\n", task->tk_status);
                 goto out;
         }
@@ -1030,7 +1013,7 @@ static void nfs_writeback_done_full(struct rpc_task *task, void *calldata)
 
                 if (task->tk_status < 0) {
                         nfs_set_pageerror(page);
-                        req->wb_context->error = task->tk_status;
+                        nfs_context_set_write_error(req->wb_context, task->tk_status);
                         dprintk(", error = %d\n", task->tk_status);
                         goto remove_request;
                 }
@@ -1244,7 +1227,7 @@ static void nfs_commit_done(struct rpc_task *task, void *calldata)
                         req->wb_bytes,
                         (long long)req_offset(req));
                 if (task->tk_status < 0) {
-                        req->wb_context->error = task->tk_status;
+                        nfs_context_set_write_error(req->wb_context, task->tk_status);
                         nfs_inode_remove_request(req);
                         dprintk(", error = %d\n", task->tk_status);
                         goto next;
@@ -1347,53 +1330,52 @@ long nfs_sync_mapping_wait(struct address_space *mapping, struct writeback_contr
         return ret;
 }
 
-/*
- * flush the inode to disk.
- */
-int nfs_wb_all(struct inode *inode)
+static int __nfs_write_mapping(struct address_space *mapping, struct writeback_control *wbc, int how)
 {
-        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,
-                .for_writepages = 1,
-                .range_cyclic = 1,
-        };
         int ret;
 
-        ret = nfs_writepages(mapping, &wbc);
+        ret = nfs_writepages(mapping, wbc);
         if (ret < 0)
                 goto out;
-        ret = nfs_sync_mapping_wait(mapping, &wbc, 0);
-        if (ret >= 0)
-                return 0;
+        ret = nfs_sync_mapping_wait(mapping, wbc, how);
+        if (ret < 0)
+                goto out;
+        return 0;
 out:
         __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
         return ret;
 }
 
-int nfs_sync_mapping_range(struct address_space *mapping, loff_t range_start, loff_t range_end, int how)
+/* Two pass sync: first using WB_SYNC_NONE, then WB_SYNC_ALL */
+static int nfs_write_mapping(struct address_space *mapping, int how)
 {
         struct writeback_control wbc = {
                 .bdi = mapping->backing_dev_info,
-                .sync_mode = WB_SYNC_ALL,
+                .sync_mode = WB_SYNC_NONE,
                 .nr_to_write = LONG_MAX,
-                .range_start = range_start,
-                .range_end = range_end,
                 .for_writepages = 1,
+                .range_cyclic = 1,
         };
         int ret;
 
-        ret = nfs_writepages(mapping, &wbc);
+        ret = __nfs_write_mapping(mapping, &wbc, how);
         if (ret < 0)
-                goto out;
-        ret = nfs_sync_mapping_wait(mapping, &wbc, how);
-        if (ret >= 0)
-                return 0;
-out:
-        __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
-        return ret;
+                return ret;
+        wbc.sync_mode = WB_SYNC_ALL;
+        return __nfs_write_mapping(mapping, &wbc, how);
+}
+
+/*
+ * flush the inode to disk.
+ */
+int nfs_wb_all(struct inode *inode)
+{
+        return nfs_write_mapping(inode->i_mapping, 0);
+}
+
+int nfs_wb_nocommit(struct inode *inode)
+{
+        return nfs_write_mapping(inode->i_mapping, FLUSH_NOCOMMIT);
 }
 
 int nfs_wb_page_cancel(struct inode *inode, struct page *page)
@@ -1477,35 +1459,6 @@ int nfs_wb_page(struct inode *inode, struct page* page)
         return nfs_wb_page_priority(inode, page, FLUSH_STABLE);
 }
 
-int nfs_set_page_dirty(struct page *page)
-{
-        struct address_space *mapping = page->mapping;
-        struct inode *inode;
-        struct nfs_page *req;
-        int ret;
-
-        if (!mapping)
-                goto out_raced;
-        inode = mapping->host;
-        if (!inode)
-                goto out_raced;
-        spin_lock(&inode->i_lock);
-        req = nfs_page_find_request_locked(page);
-        if (req != NULL) {
-                /* Mark any existing write requests for flushing */
-                ret = !test_and_set_bit(PG_NEED_FLUSH, &req->wb_flags);
-                spin_unlock(&inode->i_lock);
-                nfs_release_request(req);
-                return ret;
-        }
-        ret = __set_page_dirty_nobuffers(page);
-        spin_unlock(&inode->i_lock);
-        return ret;
-out_raced:
-        return !TestSetPageDirty(page);
-}
-
-
 int __init nfs_init_writepagecache(void)
 {
         nfs_wdata_cachep = kmem_cache_create("nfs_write_data",