scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 80 insertions, 0 deletions

diff --git a/fs/verity/pagecache.c b/fs/verity/pagecache.c
new file mode 100644
index 000000000..99f5f53ee
--- /dev/null
+++ b/fs/verity/pagecache.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Google LLC
+ */
+#include "fsverity_private.h"
+
+#include <linux/export.h>
+#include <linux/fsverity.h>
+#include <linux/pagemap.h>
+
+/**
+ * generic_read_merkle_tree_page - generic ->read_merkle_tree_page helper
+ * @inode:	inode containing the Merkle tree
+ * @index:	0-based index of the Merkle tree page in the inode
+ *
+ * The caller needs to adjust @index from the Merkle-tree relative index passed
+ * to ->read_merkle_tree_page to the actual index where the Merkle tree is
+ * stored in the page cache for @inode.
+ */
+struct page *generic_read_merkle_tree_page(struct inode *inode, pgoff_t index)
+{
+	struct folio *folio;
+
+	folio = read_mapping_folio(inode->i_mapping, index, NULL);
+	if (IS_ERR(folio))
+		return ERR_CAST(folio);
+	return folio_file_page(folio, index);
+}
+EXPORT_SYMBOL_GPL(generic_read_merkle_tree_page);
+
+/**
+ * generic_readahead_merkle_tree() - generic ->readahead_merkle_tree helper
+ * @inode:	inode containing the Merkle tree
+ * @index:	0-based index of the first Merkle tree page to read ahead in the
+ *		inode
+ * @nr_pages:	the number of Merkle tree pages that should be read ahead
+ *
+ * The caller needs to adjust @index from the Merkle-tree relative index passed
+ * to ->read_merkle_tree_page to the actual index where the Merkle tree is
+ * stored in the page cache for @inode.
+ */
+void generic_readahead_merkle_tree(struct inode *inode, pgoff_t index,
+				   unsigned long nr_pages)
+{
+	struct folio *folio;
+
+	lockdep_assert_held(&inode->i_mapping->invalidate_lock);
+
+	folio = __filemap_get_folio(inode->i_mapping, index, FGP_ACCESSED, 0);
+	if (folio == ERR_PTR(-ENOENT) ||
+	    (!IS_ERR(folio) && !folio_test_uptodate(folio))) {
+		DEFINE_READAHEAD(ractl, NULL, NULL, inode->i_mapping, index);
+
+		page_cache_ra_unbounded(&ractl, nr_pages, 0);
+	}
+	if (!IS_ERR(folio))
+		folio_put(folio);
+}
+EXPORT_SYMBOL_GPL(generic_readahead_merkle_tree);
+
+/**
+ * fsverity_fill_zerohash() - fill folio with hashes of zero data block
+ * @folio:	folio to fill
+ * @offset:	offset in the folio to start
+ * @len:	length of the range to fill with hashes
+ * @vi:		fsverity info
+ */
+void fsverity_fill_zerohash(struct folio *folio, size_t offset, size_t len,
+			      struct fsverity_info *vi)
+{
+	size_t off = offset;
+
+	WARN_ON_ONCE(!IS_ALIGNED(offset, vi->tree_params.digest_size));
+	WARN_ON_ONCE(!IS_ALIGNED(len, vi->tree_params.digest_size));
+
+	for (; off < (offset + len); off += vi->tree_params.digest_size)
+		memcpy_to_folio(folio, off, vi->tree_params.zero_digest,
+				vi->tree_params.digest_size);
+}
+EXPORT_SYMBOL_GPL(fsverity_fill_zerohash);