1 files changed, 126 insertions, 0 deletions
diff --git a/include/linux/devcoredump.h b/include/linux/devcoredump.h
new file mode 100644
index 000000000000..377892604ff4
--- /dev/null
+++ b/include/linux/devcoredump.h
@@ -0,0 +1,126 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright(c) 2015 Intel Deutschland GmbH
+ */
+#ifndef __DEVCOREDUMP_H
+#define __DEVCOREDUMP_H
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+/* if data isn't read by userspace after 5 minutes then delete it */
+#define DEVCD_TIMEOUT	(HZ * 60 * 5)
+
+/*
+ * _devcd_free_sgtable - free all the memory of the given scatterlist table
+ * (i.e. both pages and scatterlist instances)
+ * NOTE: if two tables allocated and chained using the sg_chain function then
+ * this function should be called only once on the first table
+ * @table: pointer to sg_table to free
+ */
+static inline void _devcd_free_sgtable(struct scatterlist *table)
+{
+	int i;
+	struct page *page;
+	struct scatterlist *iter;
+	struct scatterlist *delete_iter;
+
+	/* free pages */
+	iter = table;
+	for_each_sg(table, iter, sg_nents(table), i) {
+		page = sg_page(iter);
+		if (page)
+			__free_page(page);
+	}
+
+	/* then free all chained tables */
+	iter = table;
+	delete_iter = table;	/* always points on a head of a table */
+	while (!sg_is_last(iter)) {
+		iter++;
+		if (sg_is_chain(iter)) {
+			iter = sg_chain_ptr(iter);
+			kfree(delete_iter);
+			delete_iter = iter;
+		}
+	}
+
+	/* free the last table */
+	kfree(delete_iter);
+}
+
+#ifdef CONFIG_DEV_COREDUMP
+void dev_coredumpv(struct device *dev, void *data, size_t datalen,
+		   gfp_t gfp);
+
+void dev_coredumpm_timeout(struct device *dev, struct module *owner,
+			   void *data, size_t datalen, gfp_t gfp,
+			   ssize_t (*read)(char *buffer, loff_t offset,
+					   size_t count, void *data,
+					   size_t datalen),
+			   void (*free)(void *data),
+			   unsigned long timeout);
+
+void dev_coredumpsg(struct device *dev, struct scatterlist *table,
+		    size_t datalen, gfp_t gfp);
+
+void dev_coredump_put(struct device *dev);
+#else
+static inline void dev_coredumpv(struct device *dev, void *data,
+				 size_t datalen, gfp_t gfp)
+{
+	vfree(data);
+}
+
+static inline void
+dev_coredumpm_timeout(struct device *dev, struct module *owner,
+		      void *data, size_t datalen, gfp_t gfp,
+		      ssize_t (*read)(char *buffer, loff_t offset,
+				      size_t count, void *data,
+				      size_t datalen),
+		      void (*free)(void *data),
+		      unsigned long timeout)
+{
+	free(data);
+}
+
+static inline void dev_coredumpsg(struct device *dev, struct scatterlist *table,
+				  size_t datalen, gfp_t gfp)
+{
+	_devcd_free_sgtable(table);
+}
+static inline void dev_coredump_put(struct device *dev)
+{
+}
+#endif /* CONFIG_DEV_COREDUMP */
+
+/**
+ * dev_coredumpm - create device coredump with read/free methods
+ * @dev: the struct device for the crashed device
+ * @owner: the module that contains the read/free functions, use %THIS_MODULE
+ * @data: data cookie for the @read/@free functions
+ * @datalen: length of the data
+ * @gfp: allocation flags
+ * @read: function to read from the given buffer
+ * @free: function to free the given buffer
+ *
+ * Creates a new device coredump for the given device. If a previous one hasn't
+ * been read yet, the new coredump is discarded. The data lifetime is determined
+ * by the device coredump framework and when it is no longer needed the @free
+ * function will be called to free the data.
+ */
+static inline void dev_coredumpm(struct device *dev, struct module *owner,
+				 void *data, size_t datalen, gfp_t gfp,
+				 ssize_t (*read)(char *buffer, loff_t offset, size_t count,
+						 void *data, size_t datalen),
+				void (*free)(void *data))
+{
+	dev_coredumpm_timeout(dev, owner, data, datalen, gfp, read, free,
+			      DEVCD_TIMEOUT);
+}
+
+#endif /* __DEVCOREDUMP_H */