return rc;
}
+static struct cifs_writedata *
+wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
+ pgoff_t end, pgoff_t *index,
+ unsigned int *found_pages)
+{
+ unsigned int nr_pages;
+ struct page **pages;
+ struct cifs_writedata *wdata;
+
+ wdata = cifs_writedata_alloc((unsigned int)tofind,
+ cifs_writev_complete);
+ if (!wdata)
+ return NULL;
+
+ /*
+ * find_get_pages_tag seems to return a max of 256 on each
+ * iteration, so we must call it several times in order to
+ * fill the array or the wsize is effectively limited to
+ * 256 * PAGE_CACHE_SIZE.
+ */
+ *found_pages = 0;
+ pages = wdata->pages;
+ do {
+ nr_pages = find_get_pages_tag(mapping, index,
+ PAGECACHE_TAG_DIRTY, tofind,
+ pages);
+ *found_pages += nr_pages;
+ tofind -= nr_pages;
+ pages += nr_pages;
+ } while (nr_pages && tofind && *index <= end);
+
+ return wdata;
+}
+
+static unsigned int
+wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
+ struct address_space *mapping,
+ struct writeback_control *wbc,
+ pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
+{
+ unsigned int nr_pages = 0, i;
+ struct page *page;
+
+ for (i = 0; i < found_pages; i++) {
+ page = wdata->pages[i];
+ /*
+ * At this point we hold neither mapping->tree_lock nor
+ * lock on the page itself: the page may be truncated or
+ * invalidated (changing page->mapping to NULL), or even
+ * swizzled back from swapper_space to tmpfs file
+ * mapping
+ */
+
+ if (nr_pages == 0)
+ lock_page(page);
+ else if (!trylock_page(page))
+ break;
+
+ if (unlikely(page->mapping != mapping)) {
+ unlock_page(page);
+ break;
+ }
+
+ if (!wbc->range_cyclic && page->index > end) {
+ *done = true;
+ unlock_page(page);
+ break;
+ }
+
+ if (*next && (page->index != *next)) {
+ /* Not next consecutive page */
+ unlock_page(page);
+ break;
+ }
+
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+
+ if (PageWriteback(page) ||
+ !clear_page_dirty_for_io(page)) {
+ unlock_page(page);
+ break;
+ }
+
+ /*
+ * This actually clears the dirty bit in the radix tree.
+ * See cifs_writepage() for more commentary.
+ */
+ set_page_writeback(page);
+ if (page_offset(page) >= i_size_read(mapping->host)) {
+ *done = true;
+ unlock_page(page);
+ end_page_writeback(page);
+ break;
+ }
+
+ wdata->pages[i] = page;
+ *next = page->index + 1;
+ ++nr_pages;
+ }
+
+ /* reset index to refind any pages skipped */
+ if (nr_pages == 0)
+ *index = wdata->pages[0]->index + 1;
+
+ /* put any pages we aren't going to use */
+ for (i = nr_pages; i < found_pages; i++) {
+ page_cache_release(wdata->pages[i]);
+ wdata->pages[i] = NULL;
+ }
+
+ return nr_pages;
+}
+
+static int
+wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
+ struct address_space *mapping, struct writeback_control *wbc)
+{
+ int rc = 0;
+ struct TCP_Server_Info *server;
+ unsigned int i;
+
+ wdata->sync_mode = wbc->sync_mode;
+ wdata->nr_pages = nr_pages;
+ wdata->offset = page_offset(wdata->pages[0]);
+ wdata->pagesz = PAGE_CACHE_SIZE;
+ wdata->tailsz = min(i_size_read(mapping->host) -
+ page_offset(wdata->pages[nr_pages - 1]),
+ (loff_t)PAGE_CACHE_SIZE);
+ wdata->bytes = ((nr_pages - 1) * PAGE_CACHE_SIZE) + wdata->tailsz;
+
+ do {
+ if (wdata->cfile != NULL)
+ cifsFileInfo_put(wdata->cfile);
+ wdata->cfile = find_writable_file(CIFS_I(mapping->host), false);
+ if (!wdata->cfile) {
+ cifs_dbg(VFS, "No writable handles for inode\n");
+ rc = -EBADF;
+ break;
+ }
+ wdata->pid = wdata->cfile->pid;
+ server = tlink_tcon(wdata->cfile->tlink)->ses->server;
+ rc = server->ops->async_writev(wdata, cifs_writedata_release);
+ } while (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN);
+
+ for (i = 0; i < nr_pages; ++i)
+ unlock_page(wdata->pages[i]);
+
+ return rc;
+}
+
static int cifs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
bool done = false, scanned = false, range_whole = false;
pgoff_t end, index;
struct cifs_writedata *wdata;
- struct TCP_Server_Info *server;
- struct page *page;
int rc = 0;
/*
while (!done && index <= end) {
unsigned int i, nr_pages, found_pages;
pgoff_t next = 0, tofind;
- struct page **pages;
tofind = min((cifs_sb->wsize / PAGE_CACHE_SIZE) - 1,
end - index) + 1;
- wdata = cifs_writedata_alloc((unsigned int)tofind,
- cifs_writev_complete);
+ wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
+ &found_pages);
if (!wdata) {
rc = -ENOMEM;
break;
}
- /*
- * find_get_pages_tag seems to return a max of 256 on each
- * iteration, so we must call it several times in order to
- * fill the array or the wsize is effectively limited to
- * 256 * PAGE_CACHE_SIZE.
- */
- found_pages = 0;
- pages = wdata->pages;
- do {
- nr_pages = find_get_pages_tag(mapping, &index,
- PAGECACHE_TAG_DIRTY,
- tofind, pages);
- found_pages += nr_pages;
- tofind -= nr_pages;
- pages += nr_pages;
- } while (nr_pages && tofind && index <= end);
-
if (found_pages == 0) {
kref_put(&wdata->refcount, cifs_writedata_release);
break;
}
- nr_pages = 0;
- for (i = 0; i < found_pages; i++) {
- page = wdata->pages[i];
- /*
- * At this point we hold neither mapping->tree_lock nor
- * lock on the page itself: the page may be truncated or
- * invalidated (changing page->mapping to NULL), or even
- * swizzled back from swapper_space to tmpfs file
- * mapping
- */
-
- if (nr_pages == 0)
- lock_page(page);
- else if (!trylock_page(page))
- break;
-
- if (unlikely(page->mapping != mapping)) {
- unlock_page(page);
- break;
- }
-
- if (!wbc->range_cyclic && page->index > end) {
- done = true;
- unlock_page(page);
- break;
- }
-
- if (next && (page->index != next)) {
- /* Not next consecutive page */
- unlock_page(page);
- break;
- }
-
- if (wbc->sync_mode != WB_SYNC_NONE)
- wait_on_page_writeback(page);
-
- if (PageWriteback(page) ||
- !clear_page_dirty_for_io(page)) {
- unlock_page(page);
- break;
- }
-
- /*
- * This actually clears the dirty bit in the radix tree.
- * See cifs_writepage() for more commentary.
- */
- set_page_writeback(page);
-
- if (page_offset(page) >= i_size_read(mapping->host)) {
- done = true;
- unlock_page(page);
- end_page_writeback(page);
- break;
- }
-
- wdata->pages[i] = page;
- next = page->index + 1;
- ++nr_pages;
- }
-
- /* reset index to refind any pages skipped */
- if (nr_pages == 0)
- index = wdata->pages[0]->index + 1;
-
- /* put any pages we aren't going to use */
- for (i = nr_pages; i < found_pages; i++) {
- page_cache_release(wdata->pages[i]);
- wdata->pages[i] = NULL;
- }
+ nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
+ end, &index, &next, &done);
/* nothing to write? */
if (nr_pages == 0) {
continue;
}
- wdata->sync_mode = wbc->sync_mode;
- wdata->nr_pages = nr_pages;
- wdata->offset = page_offset(wdata->pages[0]);
- wdata->pagesz = PAGE_CACHE_SIZE;
- wdata->tailsz =
- min(i_size_read(mapping->host) -
- page_offset(wdata->pages[nr_pages - 1]),
- (loff_t)PAGE_CACHE_SIZE);
- wdata->bytes = ((nr_pages - 1) * PAGE_CACHE_SIZE) +
- wdata->tailsz;
-
- do {
- if (wdata->cfile != NULL)
- cifsFileInfo_put(wdata->cfile);
- wdata->cfile = find_writable_file(CIFS_I(mapping->host),
- false);
- if (!wdata->cfile) {
- cifs_dbg(VFS, "No writable handles for inode\n");
- rc = -EBADF;
- break;
- }
- wdata->pid = wdata->cfile->pid;
- server = tlink_tcon(wdata->cfile->tlink)->ses->server;
- rc = server->ops->async_writev(wdata,
- cifs_writedata_release);
- } while (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN);
-
- for (i = 0; i < nr_pages; ++i)
- unlock_page(wdata->pages[i]);
+ rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
/* send failure -- clean up the mess */
if (rc != 0) {
total_read += result;
}
- return total_read > 0 ? total_read : result;
+ return total_read > 0 && result != -EAGAIN ? total_read : result;
}
ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
total_read += result;
}
- return total_read > 0 ? total_read : result;
+ return total_read > 0 && result != -EAGAIN ? total_read : result;
}
static int cifs_readpages(struct file *file, struct address_space *mapping,