Merge tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the "big" driver core update for 4.7-rc1.

  Mostly just debugfs changes, the long-known and messy races with
  removing debugfs files should be fixed thanks to the great work of
  Nicolai Stange.  We also have some isa updates in here (the x86
  maintainers told me to take it through this tree), a new warning when
  we run out of dynamic char major numbers, and a few other assorted
  changes, details in the shortlog.

  All have been in linux-next for some time with no reported issues"

* tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits)
  Revert "base: dd: don't remove driver_data in -EPROBE_DEFER case"
  gpio: ws16c48: Utilize the ISA bus driver
  gpio: 104-idio-16: Utilize the ISA bus driver
  gpio: 104-idi-48: Utilize the ISA bus driver
  gpio: 104-dio-48e: Utilize the ISA bus driver
  watchdog: ebc-c384_wdt: Utilize the ISA bus driver
  iio: stx104: Utilize the module_isa_driver and max_num_isa_dev macros
  iio: stx104: Add X86 dependency to STX104 Kconfig option
  Documentation: Add ISA bus driver documentation
  isa: Implement the max_num_isa_dev macro
  isa: Implement the module_isa_driver macro
  pnp: pnpbios: Add explicit X86_32 dependency to PNPBIOS
  isa: Decouple X86_32 dependency from the ISA Kconfig option
  driver-core: use 'dev' argument in dev_dbg_ratelimited stub
  base: dd: don't remove driver_data in -EPROBE_DEFER case
  kernfs: Move faulting copy_user operations outside of the mutex
  devcoredump: add scatterlist support
  debugfs: unproxify files created through debugfs_create_u32_array()
  debugfs: unproxify files created through debugfs_create_blob()
  debugfs: unproxify files created through debugfs_create_bool()
  ...

1 files changed, 78 insertions, 8 deletions

diff --git a/include/linux/devcoredump.h b/include/linux/devcoredump.h
index c0a360e99f64..269521f143ac 100644
--- a/include/linux/devcoredump.h
+++ b/include/linux/devcoredump.h
@@ -1,3 +1,22 @@
+/*
+ * This file is provided under the GPLv2 license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2015 Intel Deutschland GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called COPYING.
+ */
 #ifndef __DEVCOREDUMP_H
 #define __DEVCOREDUMP_H
 
@@ -5,17 +24,62 @@
 #include <linux/module.h>
 #include <linux/vmalloc.h>
 
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+/*
+ * _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, const void *data, size_t datalen,
+void dev_coredumpv(struct device *dev, void *data, size_t datalen,
 		   gfp_t gfp);
 
 void dev_coredumpm(struct device *dev, struct module *owner,
-		   const void *data, size_t datalen, gfp_t gfp,
+		   void *data, size_t datalen, gfp_t gfp,
 		   ssize_t (*read)(char *buffer, loff_t offset, size_t count,
-				   const void *data, size_t datalen),
-		   void (*free)(const void *data));
+				   void *data, size_t datalen),
+		   void (*free)(void *data));
+
+void dev_coredumpsg(struct device *dev, struct scatterlist *table,
+		    size_t datalen, gfp_t gfp);
 #else
-static inline void dev_coredumpv(struct device *dev, const void *data,
+static inline void dev_coredumpv(struct device *dev, void *data,
 				 size_t datalen, gfp_t gfp)
 {
 	vfree(data);
@@ -23,13 +87,19 @@ static inline void dev_coredumpv(struct device *dev, const void *data,
 
 static inline void
 dev_coredumpm(struct device *dev, struct module *owner,
-	      const void *data, size_t datalen, gfp_t gfp,
+	      void *data, size_t datalen, gfp_t gfp,
 	      ssize_t (*read)(char *buffer, loff_t offset, size_t count,
-			      const void *data, size_t datalen),
-	      void (*free)(const void *data))
+			      void *data, size_t datalen),
+	      void (*free)(void *data))
 {
 	free(data);
 }
+
+static inline void dev_coredumpsg(struct device *dev, struct scatterlist *table,
+				  size_t datalen, gfp_t gfp)
+{
+	_devcd_free_sgtable(table);
+}
 #endif /* CONFIG_DEV_COREDUMP */
 
 #endif /* __DEVCOREDUMP_H */