CIFS: Fix cifs_writev_requeue when wsize changes

If wsize changes on reconnect we need to use new writedata structure
that for retrying.

Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 68 insertions, 16 deletions

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index b7e5b6508caa..52cfd8cf0db0 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1896,28 +1896,80 @@ cifs_writedata_release(struct kref *refcount)
 static void
 cifs_writev_requeue(struct cifs_writedata *wdata)
 {
-        int i, rc;
+        int i, rc = 0;
         struct inode *inode = wdata->cfile->dentry->d_inode;
         struct TCP_Server_Info *server;
+        unsigned int rest_len;
 
-        for (i = 0; i < wdata->nr_pages; i++) {
-                lock_page(wdata->pages[i]);
-                clear_page_dirty_for_io(wdata->pages[i]);
-        }
-
+        server = tlink_tcon(wdata->cfile->tlink)->ses->server;
+        i = 0;
+        rest_len = wdata->bytes;
         do {
-                server = tlink_tcon(wdata->cfile->tlink)->ses->server;
-                rc = server->ops->async_writev(wdata, cifs_writedata_release);
-        } while (rc == -EAGAIN);
+                struct cifs_writedata *wdata2;
+                unsigned int j, nr_pages, wsize, tailsz, cur_len;
+
+                wsize = server->ops->wp_retry_size(inode);
+                if (wsize < rest_len) {
+                        nr_pages = wsize / PAGE_CACHE_SIZE;
+                        if (!nr_pages) {
+                                rc = -ENOTSUPP;
+                                break;
+                        }
+                        cur_len = nr_pages * PAGE_CACHE_SIZE;
+                        tailsz = PAGE_CACHE_SIZE;
+                } else {
+                        nr_pages = DIV_ROUND_UP(rest_len, PAGE_CACHE_SIZE);
+                        cur_len = rest_len;
+                        tailsz = rest_len - (nr_pages - 1) * PAGE_CACHE_SIZE;
+                }
 
-        for (i = 0; i < wdata->nr_pages; i++) {
-                unlock_page(wdata->pages[i]);
-                if (rc != 0) {
-                        SetPageError(wdata->pages[i]);
-                        end_page_writeback(wdata->pages[i]);
-                        page_cache_release(wdata->pages[i]);
+                wdata2 = cifs_writedata_alloc(nr_pages, cifs_writev_complete);
+                if (!wdata2) {
+                        rc = -ENOMEM;
+                        break;
                 }
-        }
+
+                for (j = 0; j < nr_pages; j++) {
+                        wdata2->pages[j] = wdata->pages[i + j];
+                        lock_page(wdata2->pages[j]);
+                        clear_page_dirty_for_io(wdata2->pages[j]);
+                }
+
+                wdata2->sync_mode = wdata->sync_mode;
+                wdata2->nr_pages = nr_pages;
+                wdata2->offset = page_offset(wdata2->pages[0]);
+                wdata2->pagesz = PAGE_CACHE_SIZE;
+                wdata2->tailsz = tailsz;
+                wdata2->bytes = cur_len;
+
+                wdata2->cfile = find_writable_file(CIFS_I(inode), false);
+                if (!wdata2->cfile) {
+                        cifs_dbg(VFS, "No writable handles for inode\n");
+                        rc = -EBADF;
+                        break;
+                }
+                wdata2->pid = wdata2->cfile->pid;
+                rc = server->ops->async_writev(wdata2, cifs_writedata_release);
+
+                for (j = 0; j < nr_pages; j++) {
+                        unlock_page(wdata2->pages[j]);
+                        if (rc != 0 && rc != -EAGAIN) {
+                                SetPageError(wdata2->pages[j]);
+                                end_page_writeback(wdata2->pages[j]);
+                                page_cache_release(wdata2->pages[j]);
+                        }
+                }
+
+                if (rc) {
+                        kref_put(&wdata2->refcount, cifs_writedata_release);
+                        if (rc == -EAGAIN)
+                                continue;
+                        break;
+                }
+
+                rest_len -= cur_len;
+                i += nr_pages;
+        } while (i < wdata->nr_pages);
 
         mapping_set_error(inode->i_mapping, rc);
         kref_put(&wdata->refcount, cifs_writedata_release);