Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 67 insertions, 0 deletions

diff --git a/mm/failslab.c b/mm/failslab.c
new file mode 100644
index 000000000..b135ebb88
--- /dev/null
+++ b/mm/failslab.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/fault-inject.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include "slab.h"
+
+static struct {
+	struct fault_attr attr;
+	bool ignore_gfp_reclaim;
+	bool cache_filter;
+} failslab = {
+	.attr = FAULT_ATTR_INITIALIZER,
+	.ignore_gfp_reclaim = true,
+	.cache_filter = false,
+};
+
+bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
+{
+	/* No fault-injection for bootstrap cache */
+	if (unlikely(s == kmem_cache))
+		return false;
+
+	if (gfpflags & __GFP_NOFAIL)
+		return false;
+
+	if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
+		return false;
+
+	if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
+		return false;
+
+	return should_fail(&failslab.attr, s->object_size);
+}
+
+static int __init setup_failslab(char *str)
+{
+	return setup_fault_attr(&failslab.attr, str);
+}
+__setup("failslab=", setup_failslab);
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+static int __init failslab_debugfs_init(void)
+{
+	struct dentry *dir;
+	umode_t mode = S_IFREG | 0600;
+
+	dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+
+	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
+				&failslab.ignore_gfp_reclaim))
+		goto fail;
+	if (!debugfs_create_bool("cache-filter", mode, dir,
+				&failslab.cache_filter))
+		goto fail;
+
+	return 0;
+fail:
+	debugfs_remove_recursive(dir);
+
+	return -ENOMEM;
+}
+
+late_initcall(failslab_debugfs_init);
+
+#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */