NFS: Add nfs_commit_file()

Copy will use this to set up a commit request for a generic range.  I
don't want to allocate a new pagecache entry for the file, so I needed
to change parts of the commit path to handle requests with a null
wb_page.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index f1d1d2c..5154fa6 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -477,6 +477,7 @@ void nfs_mark_request_commit(struct nfs_page *req,
                             u32 ds_commit_idx);
 int nfs_write_need_commit(struct nfs_pgio_header *);
 void nfs_writeback_update_inode(struct nfs_pgio_header *hdr);
+int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf);
 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
                            int how, struct nfs_commit_info *cinfo);
 void nfs_retry_commit(struct list_head *page_list,

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 1f6db42..174dd4c 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -341,8 +341,10 @@ nfs_create_request(struct nfs_open_context *ctx, struct page *page,
         * long write-back delay. This will be adjusted in
         * update_nfs_request below if the region is not locked. */
        req->wb_page    = page;
-       req->wb_index   = page_file_index(page);
-       get_page(page);
+       if (page) {
+               req->wb_index = page_file_index(page);
+               get_page(page);
+       }
        req->wb_offset  = offset;
        req->wb_pgbase  = offset;
        req->wb_bytes   = count;

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 9283a96..e18a97a 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -737,7 +737,7 @@ static void nfs_inode_remove_request(struct nfs_page *req)
                head = req->wb_head;
 
                spin_lock(&inode->i_lock);
-               if (likely(!PageSwapCache(head->wb_page))) {
+               if (likely(head->wb_page && !PageSwapCache(head->wb_page))) {
                        set_page_private(head->wb_page, 0);
                        ClearPagePrivate(head->wb_page);
                        smp_mb__after_atomic();
@@ -759,7 +759,8 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 static void
 nfs_mark_request_dirty(struct nfs_page *req)
 {
-       __set_page_dirty_nobuffers(req->wb_page);
+       if (req->wb_page)
+               __set_page_dirty_nobuffers(req->wb_page);
 }
 
 /*
@@ -835,7 +836,8 @@ nfs_request_add_commit_list(struct nfs_page *req, struct nfs_commit_info *cinfo)
        spin_lock(&cinfo->inode->i_lock);
        nfs_request_add_commit_list_locked(req, &cinfo->mds->list, cinfo);
        spin_unlock(&cinfo->inode->i_lock);
-       nfs_mark_page_unstable(req->wb_page, cinfo);
+       if (req->wb_page)
+               nfs_mark_page_unstable(req->wb_page, cinfo);
 }
 EXPORT_SYMBOL_GPL(nfs_request_add_commit_list);
 
@@ -1724,6 +1726,36 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how,
        return -ENOMEM;
 }
 
+int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf)
+{
+       struct inode *inode = file_inode(file);
+       struct nfs_open_context *open;
+       struct nfs_commit_info cinfo;
+       struct nfs_page *req;
+       int ret;
+
+       open = get_nfs_open_context(nfs_file_open_context(file));
+       req  = nfs_create_request(open, NULL, NULL, 0, i_size_read(inode));
+       if (!req) {
+               ret = -ENOMEM;
+               goto out_put;
+       }
+
+       nfs_init_cinfo_from_inode(&cinfo, inode);
+
+       memcpy(&req->wb_verf, verf, sizeof(struct nfs_write_verifier));
+       nfs_request_add_commit_list(req, &cinfo);
+       ret = nfs_commit_inode(inode, FLUSH_SYNC);
+       if (ret > 0)
+               ret = 0;
+
+       nfs_free_request(req);
+out_put:
+       put_nfs_open_context(open);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(nfs_commit_file);
+
 /*
  * COMMIT call returned
  */
@@ -1748,7 +1780,8 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data)
        while (!list_empty(&data->pages)) {
                req = nfs_list_entry(data->pages.next);
                nfs_list_remove_request(req);
-               nfs_clear_page_commit(req->wb_page);
+               if (req->wb_page)
+                       nfs_clear_page_commit(req->wb_page);
 
                dprintk("NFS:       commit (%s/%llu %d@%lld)",
                        req->wb_context->dentry->d_sb->s_id,