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authorThomas Hellström <thomas.hellstrom@linux.intel.com>2025-12-19 11:51:22 +0100
committerThomas Hellström <thomas.hellstrom@linux.intel.com>2025-12-19 11:51:22 +0100
commit5add3c3c280a35f7e258e9cef7607db5a2e56fdc (patch)
tree22eca9a4a1003a64933980bf76da2fbe8a74f759 /include/linux/livepatch_external.h
parentc7b83a916d62c4d4447d7edf0bc5e06dc2afbdf8 (diff)
parent8f0b4cce4481fb22653697cced8d0d04027cb1e8 (diff)
Merge drm/drm-next into drm-xe-next
Backmerging to bring in 6.19-rc1. An important upstream bugfix and to help unblock PTL CI. Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Diffstat (limited to 'include/linux/livepatch_external.h')
-rw-r--r--include/linux/livepatch_external.h76
1 files changed, 76 insertions, 0 deletions
diff --git a/include/linux/livepatch_external.h b/include/linux/livepatch_external.h
new file mode 100644
index 000000000000..138af19b0f5c
--- /dev/null
+++ b/include/linux/livepatch_external.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * External livepatch interfaces for patch creation tooling
+ */
+
+#ifndef _LINUX_LIVEPATCH_EXTERNAL_H_
+#define _LINUX_LIVEPATCH_EXTERNAL_H_
+
+#include <linux/types.h>
+
+#define KLP_RELOC_SEC_PREFIX ".klp.rela."
+#define KLP_SYM_PREFIX ".klp.sym."
+
+#define __KLP_PRE_PATCH_PREFIX __klp_pre_patch_callback_
+#define __KLP_POST_PATCH_PREFIX __klp_post_patch_callback_
+#define __KLP_PRE_UNPATCH_PREFIX __klp_pre_unpatch_callback_
+#define __KLP_POST_UNPATCH_PREFIX __klp_post_unpatch_callback_
+
+#define KLP_PRE_PATCH_PREFIX __stringify(__KLP_PRE_PATCH_PREFIX)
+#define KLP_POST_PATCH_PREFIX __stringify(__KLP_POST_PATCH_PREFIX)
+#define KLP_PRE_UNPATCH_PREFIX __stringify(__KLP_PRE_UNPATCH_PREFIX)
+#define KLP_POST_UNPATCH_PREFIX __stringify(__KLP_POST_UNPATCH_PREFIX)
+
+struct klp_object;
+
+typedef int (*klp_pre_patch_t)(struct klp_object *obj);
+typedef void (*klp_post_patch_t)(struct klp_object *obj);
+typedef void (*klp_pre_unpatch_t)(struct klp_object *obj);
+typedef void (*klp_post_unpatch_t)(struct klp_object *obj);
+
+/**
+ * struct klp_callbacks - pre/post live-(un)patch callback structure
+ * @pre_patch: executed before code patching
+ * @post_patch: executed after code patching
+ * @pre_unpatch: executed before code unpatching
+ * @post_unpatch: executed after code unpatching
+ * @post_unpatch_enabled: flag indicating if post-unpatch callback
+ * should run
+ *
+ * All callbacks are optional. Only the pre-patch callback, if provided,
+ * will be unconditionally executed. If the parent klp_object fails to
+ * patch for any reason, including a non-zero error status returned from
+ * the pre-patch callback, no further callbacks will be executed.
+ */
+struct klp_callbacks {
+ klp_pre_patch_t pre_patch;
+ klp_post_patch_t post_patch;
+ klp_pre_unpatch_t pre_unpatch;
+ klp_post_unpatch_t post_unpatch;
+ bool post_unpatch_enabled;
+};
+
+/*
+ * 'struct klp_{func,object}_ext' are compact "external" representations of
+ * 'struct klp_{func,object}'. They are used by objtool for livepatch
+ * generation. The structs are then read by the livepatch module and converted
+ * to the real structs before calling klp_enable_patch().
+ *
+ * TODO make these the official API for klp_enable_patch(). That should
+ * simplify livepatch's interface as well as its data structure lifetime
+ * management.
+ */
+struct klp_func_ext {
+ const char *old_name;
+ void *new_func;
+ unsigned long sympos;
+};
+
+struct klp_object_ext {
+ const char *name;
+ struct klp_func_ext *funcs;
+ struct klp_callbacks callbacks;
+ unsigned int nr_funcs;
+};
+
+#endif /* _LINUX_LIVEPATCH_EXTERNAL_H_ */