summaryrefslogtreecommitdiff
path: root/include/linux/devcoredump.h
diff options
context:
space:
mode:
authorJohannes Berg <johannes.berg@intel.com>2014-09-12 11:01:56 +0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-09-24 09:53:15 +0400
commit833c95456a70826d1384883b73fd23aff24d366f (patch)
treebe9235e0df06fdc85deb13d1193b6120ed7196bd /include/linux/devcoredump.h
parent00e262fd8744678262a0f662f1b5d45fc1f52e10 (diff)
downloadlinux-833c95456a70826d1384883b73fd23aff24d366f.tar.xz
device coredump: add new device coredump class
Many devices run firmware and/or complex hardware, and most of that can have bugs. When it misbehaves, however, it is often much harder to debug than software running on the host. Introduce a "device coredump" mechanism to allow dumping internal device/firmware state through a generalized mechanism. As devices are different and information needed can vary accordingly, this doesn't prescribe a file format - it just provides mechanism to get data to be able to capture it in a generalized way (e.g. in distributions.) The dumped data will be readable in sysfs in the virtual device's data file under /sys/class/devcoredump/devcd*/. Writing to it will free the data and remove the device, as does a 5-minute timeout. Note that generalized capturing of such data may result in privacy issues, so users generally need to be involved. In order to allow certain users/system integrators/... to disable the feature at all, introduce a Kconfig option to override the drivers that would like to have the feature. For now, this provides two ways of dumping data: 1) with a vmalloc'ed area, that is then given to the subsystem and freed after retrieval or timeout 2) with a generalized reader/free function method We could/should add more options, e.g. a list of pages, since the vmalloc area is very limited on some architectures. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/devcoredump.h')
-rw-r--r--include/linux/devcoredump.h35
1 files changed, 35 insertions, 0 deletions
diff --git a/include/linux/devcoredump.h b/include/linux/devcoredump.h
new file mode 100644
index 000000000000..c0a360e99f64
--- /dev/null
+++ b/include/linux/devcoredump.h
@@ -0,0 +1,35 @@
+#ifndef __DEVCOREDUMP_H
+#define __DEVCOREDUMP_H
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+
+#ifdef CONFIG_DEV_COREDUMP
+void dev_coredumpv(struct device *dev, const 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,
+ ssize_t (*read)(char *buffer, loff_t offset, size_t count,
+ const void *data, size_t datalen),
+ void (*free)(const void *data));
+#else
+static inline void dev_coredumpv(struct device *dev, const void *data,
+ size_t datalen, gfp_t gfp)
+{
+ vfree(data);
+}
+
+static inline void
+dev_coredumpm(struct device *dev, struct module *owner,
+ const 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))
+{
+ free(data);
+}
+#endif /* CONFIG_DEV_COREDUMP */
+
+#endif /* __DEVCOREDUMP_H */