NFS: Clean up nfs_readpage() and nfs_readpages()

In prep for the new fscache netfs API, refactor nfs_readpage()
and nfs_readpages() for future patches.  No functional change.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index eb854f1..dd92156 100644 (file)
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -314,7 +314,7 @@ int nfs_readpage(struct file *file, struct page *page)
 {
        struct nfs_open_context *ctx;
        struct inode *inode = page_file_mapping(page)->host;
-       int             error;
+       int ret;
 
        dprintk("NFS: nfs_readpage (%p %ld@%lu)\n",
                page, PAGE_SIZE, page_index(page));
@@ -328,18 +328,18 @@ int nfs_readpage(struct file *file, struct page *page)
         * be any new pending writes generated at this point
         * for this page (other pages can be written to).
         */
-       error = nfs_wb_page(inode, page);
-       if (error)
+       ret = nfs_wb_page(inode, page);
+       if (ret)
                goto out_unlock;
        if (PageUptodate(page))
                goto out_unlock;
 
-       error = -ESTALE;
+       ret = -ESTALE;
        if (NFS_STALE(inode))
                goto out_unlock;
 
        if (file == NULL) {
-               error = -EBADF;
+               ret = -EBADF;
                ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
                if (ctx == NULL)
                        goto out_unlock;
@@ -347,24 +347,24 @@ int nfs_readpage(struct file *file, struct page *page)
                ctx = get_nfs_open_context(nfs_file_open_context(file));
 
        if (!IS_SYNC(inode)) {
-               error = nfs_readpage_from_fscache(ctx, inode, page);
-               if (error == 0)
+               ret = nfs_readpage_from_fscache(ctx, inode, page);
+               if (ret == 0)
                        goto out;
        }
 
        xchg(&ctx->error, 0);
-       error = nfs_readpage_async(ctx, inode, page);
-       if (!error) {
-               error = wait_on_page_locked_killable(page);
-               if (!PageUptodate(page) && !error)
-                       error = xchg(&ctx->error, 0);
+       ret = nfs_readpage_async(ctx, inode, page);
+       if (!ret) {
+               ret = wait_on_page_locked_killable(page);
+               if (!PageUptodate(page) && !ret)
+                       ret = xchg(&ctx->error, 0);
        }
 out:
        put_nfs_open_context(ctx);
-       return error;
+       return ret;
 out_unlock:
        unlock_page(page);
-       return error;
+       return ret;
 }
 
 struct nfs_readdesc {
@@ -404,17 +404,15 @@ out:
        return error;
 }
 
-int nfs_readpages(struct file *filp, struct address_space *mapping,
+int nfs_readpages(struct file *file, struct address_space *mapping,
                struct list_head *pages, unsigned nr_pages)
 {
        struct nfs_pageio_descriptor pgio;
        struct nfs_pgio_mirror *pgm;
-       struct nfs_readdesc desc = {
-               .pgio = &pgio,
-       };
+       struct nfs_readdesc desc;
        struct inode *inode = mapping->host;
        unsigned long npages;
-       int ret = -ESTALE;
+       int ret;
 
        dprintk("NFS: nfs_readpages (%s/%Lu %d)\n",
                        inode->i_sb->s_id,
@@ -422,15 +420,17 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
                        nr_pages);
        nfs_inc_stats(inode, NFSIOS_VFSREADPAGES);
 
+       ret = -ESTALE;
        if (NFS_STALE(inode))
                goto out;
 
-       if (filp == NULL) {
+       if (file == NULL) {
+               ret = -EBADF;
                desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
                if (desc.ctx == NULL)
-                       return -EBADF;
+                       goto out;
        } else
-               desc.ctx = get_nfs_open_context(nfs_file_open_context(filp));
+               desc.ctx = get_nfs_open_context(nfs_file_open_context(file));
 
        /* attempt to read as many of the pages as possible from the cache
         * - this returns -ENOBUFS immediately if the cookie is negative
@@ -440,6 +440,7 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
        if (ret == 0)
                goto read_complete; /* all pages were read */
 
+       desc.pgio = &pgio;
        nfs_pageio_init_read(&pgio, inode, false,
                             &nfs_async_read_completion_ops);