projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 156473a0 SRV |
1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | #include <linux/module.h> | |
| 3 | ||
| 4 | #include <linux/mm.h> /* for handle_mm_fault() */ | |
| 5 | #include <linux/ftrace.h> | |
| 6 | ||
| 7 | void my_direct_func(struct vm_area_struct *vma, | |
| 8 | unsigned long address, unsigned int flags) | |
| 9 | { | |
| 10 | trace_printk("handle mm fault vma=%p address=%lx flags=%x\n", | |
| 11 | vma, address, flags); | |
| 12 | } | |
| 13 | ||
| 14 | extern void my_tramp(void *); | |
| 15 | ||
| 16 | asm ( | |
| 17 | " .pushsection .text, \"ax\", @progbits\n" | |
| 9d907f1a | 18 | " .type my_tramp, @function\n" |
| 156473a0 SRV |
19 | " my_tramp:" |
| 20 | " pushq %rbp\n" | |
| 21 | " movq %rsp, %rbp\n" | |
| 22 | " pushq %rdi\n" | |
| 23 | " pushq %rsi\n" | |
| 24 | " pushq %rdx\n" | |
| 25 | " call my_direct_func\n" | |
| 26 | " popq %rdx\n" | |
| 27 | " popq %rsi\n" | |
| 28 | " popq %rdi\n" | |
| 29 | " leave\n" | |
| 30 | " ret\n" | |
| 9d907f1a | 31 | " .size my_tramp, .-my_tramp\n" |
| 156473a0 SRV |
32 | " .popsection\n" |
| 33 | ); | |
| 34 | ||
| 35 | ||
| 36 | static int __init ftrace_direct_init(void) | |
| 37 | { | |
| 38 | return register_ftrace_direct((unsigned long)handle_mm_fault, | |
| 39 | (unsigned long)my_tramp); | |
| 40 | } | |
| 41 | ||
| 42 | static void __exit ftrace_direct_exit(void) | |
| 43 | { | |
| 44 | unregister_ftrace_direct((unsigned long)handle_mm_fault, | |
| 45 | (unsigned long)my_tramp); | |
| 46 | } | |
| 47 | ||
| 48 | module_init(ftrace_direct_init); | |
| 49 | module_exit(ftrace_direct_exit); | |
| 50 | ||
| 51 | MODULE_AUTHOR("Steven Rostedt"); | |
| 52 | MODULE_DESCRIPTION("Another example use case of using register_ftrace_direct()"); | |
| 53 | MODULE_LICENSE("GPL"); |