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-rw-r--r--include/linux/compiler-gcc6.h65
-rw-r--r--include/linux/device.h21
2 files changed, 86 insertions, 0 deletions
diff --git a/include/linux/compiler-gcc6.h b/include/linux/compiler-gcc6.h
new file mode 100644
index 00000000000..622117be664
--- /dev/null
+++ b/include/linux/compiler-gcc6.h
@@ -0,0 +1,65 @@
+#ifndef __LINUX_COMPILER_H
+#error "Please don't include <linux/compiler-gcc6.h> directly, include <linux/compiler.h> instead."
+#endif
+
+#define __used __attribute__((__used__))
+#define __must_check __attribute__((warn_unused_result))
+#define __compiler_offsetof(a, b) __builtin_offsetof(a, b)
+
+/* Mark functions as cold. gcc will assume any path leading to a call
+ to them will be unlikely. This means a lot of manual unlikely()s
+ are unnecessary now for any paths leading to the usual suspects
+ like BUG(), printk(), panic() etc. [but let's keep them for now for
+ older compilers]
+
+ Early snapshots of gcc 4.3 don't support this and we can't detect this
+ in the preprocessor, but we can live with this because they're unreleased.
+ Maketime probing would be overkill here.
+
+ gcc also has a __attribute__((__hot__)) to move hot functions into
+ a special section, but I don't see any sense in this right now in
+ the kernel context */
+#define __cold __attribute__((__cold__))
+
+#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
+
+#ifndef __CHECKER__
+# define __compiletime_warning(message) __attribute__((warning(message)))
+# define __compiletime_error(message) __attribute__((error(message)))
+#endif /* __CHECKER__ */
+
+/*
+ * Mark a position in code as unreachable. This can be used to
+ * suppress control flow warnings after asm blocks that transfer
+ * control elsewhere.
+ *
+ * Early snapshots of gcc 4.5 don't support this and we can't detect
+ * this in the preprocessor, but we can live with this because they're
+ * unreleased. Really, we need to have autoconf for the kernel.
+ */
+#define unreachable() __builtin_unreachable()
+
+/* Mark a function definition as prohibited from being cloned. */
+#define __noclone __attribute__((__noclone__))
+
+/*
+ * Tell the optimizer that something else uses this function or variable.
+ */
+#define __visible __attribute__((externally_visible))
+
+/*
+ * GCC 'asm goto' miscompiles certain code sequences:
+ *
+ * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
+ *
+ * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
+ *
+ * (asm goto is automatically volatile - the naming reflects this.)
+ */
+#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
+
+#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP
+#define __HAVE_BUILTIN_BSWAP32__
+#define __HAVE_BUILTIN_BSWAP64__
+#define __HAVE_BUILTIN_BSWAP16__
+#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
diff --git a/include/linux/device.h b/include/linux/device.h
index 074d4503731..5ba4a30611e 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -72,6 +72,10 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
* the specific driver's probe to initial the matched device.
* @remove: Called when a device removed from this bus.
* @shutdown: Called at shut-down time to quiesce the device.
+ *
+ * @online: Called to put the device back online (after offlining it).
+ * @offline: Called to put the device offline for hot-removal. May fail.
+ *
* @suspend: Called when a device on this bus wants to go to sleep mode.
* @resume: Called to bring a device on this bus out of sleep mode.
* @pm: Power management operations of this bus, callback the specific
@@ -105,6 +109,9 @@ struct bus_type {
int (*remove)(struct device *dev);
void (*shutdown)(struct device *dev);
+ int (*online)(struct device *dev);
+ int (*offline)(struct device *dev);
+
int (*suspend)(struct device *dev, pm_message_t state);
int (*resume)(struct device *dev);
@@ -672,6 +679,8 @@ struct acpi_dev_node {
* @release: Callback to free the device after all references have
* gone away. This should be set by the allocator of the
* device (i.e. the bus driver that discovered the device).
+ * @offline_disabled: If set, the device is permanently online.
+ * @offline: Set after successful invocation of bus type's .offline().
*
* At the lowest level, every device in a Linux system is represented by an
* instance of struct device. The device structure contains the information
@@ -744,6 +753,9 @@ struct device {
void (*release)(struct device *dev);
struct iommu_group *iommu_group;
+
+ bool offline_disabled:1;
+ bool offline:1;
};
static inline struct device *kobj_to_dev(struct kobject *kobj)
@@ -880,6 +892,15 @@ extern const char *device_get_devnode(struct device *dev,
extern void *dev_get_drvdata(const struct device *dev);
extern int dev_set_drvdata(struct device *dev, void *data);
+static inline bool device_supports_offline(struct device *dev)
+{
+ return dev->bus && dev->bus->offline && dev->bus->online;
+}
+
+extern void lock_device_hotplug(void);
+extern void unlock_device_hotplug(void);
+extern int device_offline(struct device *dev);
+extern int device_online(struct device *dev);
/*
* Root device objects for grouping under /sys/devices
*/