2 * @file kprobe/swap_kprobes.h
3 * @author Ekaterina Gorelkina <e.gorelkina@samsung.com>: initial implementation for ARM and MIPS
4 * @author Alexey Gerenkov <a.gerenkov@samsung.com> User-Space Probes initial implementation;
5 * Support x86/ARM/MIPS for both user and kernel spaces.
6 * @author Ekaterina Gorelkina <e.gorelkina@samsung.com>: redesign module for separating core and arch parts
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 * Copyright (C) IBM Corporation, 2002, 2004
27 * Copyright (C) Samsung Electronics, 2006-2010
29 * @section DESCRIPTION
31 * SWAP kprobe interface definition.
35 #ifndef _SWAP_KPROBES_H
36 #define _SWAP_KPROBES_H
38 #include <linux/version.h> // LINUX_VERSION_CODE, KERNEL_VERSION()
39 #include <linux/notifier.h>
40 #include <linux/percpu.h>
41 #include <linux/spinlock.h>
42 #include <linux/rcupdate.h>
43 #include <linux/sched.h>
44 #include <linux/pagemap.h>
46 #include <swap-asm/swap_kprobes.h>
51 #define regs_return_value(regs) ((regs)->ARM_r0)
56 /* kprobe_status settings */
57 /** Kprobe hit active */
58 #define KPROBE_HIT_ACTIVE 0x00000001
60 #define KPROBE_HIT_SS 0x00000002
62 #define KPROBE_REENTER 0x00000004
63 /** Kprobe hit ss done */
64 #define KPROBE_HIT_SSDONE 0x00000008
67 #define HIWORD(x) (((x) & 0xFFFF0000) >> 16)
69 #define LOWORD(x) ((x) & 0x0000FFFF)
72 #define INVALID_VALUE 0xFFFFFFFF
73 /** Invalid pointer */
74 #define INVALID_POINTER (void*)INVALID_VALUE
77 #define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)pentry
79 /** Retprobe stack depth */
80 #define RETPROBE_STACK_DEPTH 64
85 struct kretprobe_instance;
88 * @brief Kprobe pre-handler pointer.
90 typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
93 * @brief Kprobe break handler pointer.
95 typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
98 * @brief Kprobe post handler pointer.
100 typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *, unsigned long flags);
103 * @brief Kprobe fault handler pointer.
105 typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *, int trapnr);
108 * @brief Kretprobe handler pointer.
110 typedef int (*kretprobe_handler_t) (struct kretprobe_instance *, struct pt_regs *);
114 * @brief Main kprobe struct.
118 struct hlist_node hlist; /**< Hash list.*/
119 /** List of probes to search by instruction slot.*/
120 struct hlist_node is_hlist;
121 /** List of kprobes for multi-handler support.*/
122 struct list_head list;
123 /** Indicates that the corresponding module has been ref counted.*/
124 unsigned int mod_refcounted;
125 /** Count the number of times this probe was temporarily disarmed.*/
126 unsigned long nmissed;
127 /** Location of the probe point. */
128 kprobe_opcode_t *addr;
129 /** Allow user to indicate symbol name of the probe point.*/
131 /** Offset into the symbol.*/
133 /** Called before addr is executed.*/
134 kprobe_pre_handler_t pre_handler;
135 /** Called after addr is executed, unless...*/
136 kprobe_post_handler_t post_handler;
137 /** ... called if executing addr causes a fault (eg. page fault).*/
138 kprobe_fault_handler_t fault_handler;
139 /** Return 1 if it handled fault, otherwise kernel will see it.*/
140 kprobe_break_handler_t break_handler;
141 /** Saved opcode (which has been replaced with breakpoint).*/
142 kprobe_opcode_t opcode;
143 /** Copy of the original instruction.*/
144 struct arch_specific_insn ainsn;
145 /** Override single-step target address, may be used to redirect
146 * control-flow to arbitrary address after probe point without
147 * invocation of original instruction; useful for functions
148 * replacement. If jprobe.entry should return address of function or
149 * NULL if original function should be called.
150 * Not supported for X86, not tested for MIPS. */
151 kprobe_opcode_t *ss_addr[NR_CPUS];
153 /** Safe/unsafe to use probe on ARM.*/
155 /** Safe/unsafe to use probe on Thumb.*/
156 unsigned safe_thumb:1;
161 * @brief Kprobe pre-entry handler pointer.
163 typedef unsigned long (*kprobe_pre_entry_handler_t) (void *priv_arg, struct pt_regs * regs);
168 * @brief Special probe type that uses setjmp-longjmp type tricks to resume
169 * execution at a specified entry with a matching prototype corresponding
170 * to the probed function - a trick to enable arguments to become
171 * accessible seamlessly by probe handling logic.
173 * Because of the way compilers allocate stack space for local variables
174 * etc upfront, regardless of sub-scopes within a function, this mirroring
175 * principle currently works only for probes placed on function entry points.
179 struct kprobe kp; /**< This probes kprobe.*/
180 kprobe_opcode_t *entry; /**< Probe handling code to jump to.*/
181 /** Handler which will be called before 'entry'. */
182 kprobe_pre_entry_handler_t pre_entry;
183 void *priv_arg; /**< Private args.*/
188 * @struct jprobe_instance
189 * @brief Jprobe instance struct.
191 struct jprobe_instance
193 // either on free list or used list
194 struct hlist_node uflist; /**< Jprobes hash list. */
195 struct hlist_node hlist; /**< Jprobes hash list. */
196 struct jprobe *jp; /**< Pointer to the target jprobe. */
197 /** Pointer to the target task_struct. */
198 struct task_struct *task;
207 * @brief Function-return probe
208 * Note: User needs to provide a handler function, and initialize maxactive.
212 struct kprobe kp; /**< Kprobe of this kretprobe.*/
213 kretprobe_handler_t handler; /**< Handler of this kretprobe.*/
214 kretprobe_handler_t entry_handler; /**< Entry handler of this kretprobe.*/
215 /** The maximum number of instances of the probed function that can be
216 * active concurrently. */
218 /** Tracks the number of times the probed function's return was ignored,
219 * due to maxactive being too low. */
221 size_t data_size; /**< Size of the data. */
222 /** List of this probe's free_instances. */
223 struct hlist_head free_instances;
224 /** List of this probe's used_instances. */
225 struct hlist_head used_instances;
228 unsigned arm_noret:1; /**< No-return flag for ARM.*/
229 unsigned thumb_noret:1; /**< No-return flag for Thumb.*/
235 * @struct kretprobe_instance
236 * @brief Instance of kretprobe.
238 struct kretprobe_instance
240 // either on free list or used list
241 struct hlist_node uflist; /**< Kretprobe hash list.*/
242 struct hlist_node hlist; /**< Kretprobe hash list.*/
243 struct kretprobe *rp; /**< Pointer to this instance's kretprobe.*/
244 unsigned long *ret_addr; /**< Return address.*/
245 unsigned long *sp; /**< Stack pointer.*/
246 struct task_struct *task; /**< Pointer to the target task_struct.*/
247 char data[0]; /**< Pointer to data.*/
251 extern void swap_kprobes_inc_nmissed_count(struct kprobe *p);
254 // Large value for fast but memory consuming implementation
255 // it is good when a lot of probes are instrumented
257 //#define KPROBE_HASH_BITS 6
258 #define KPROBE_HASH_BITS 16
259 #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS)
262 /* Get the kprobe at this addr (if any) - called with preemption disabled */
263 struct kprobe *swap_get_kprobe(void *addr);
266 int swap_register_kprobe(struct kprobe *p);
267 void swap_unregister_kprobe(struct kprobe *p);
269 int swap_setjmp_pre_handler(struct kprobe *, struct pt_regs *);
270 int swap_longjmp_break_handler(struct kprobe *, struct pt_regs *);
272 int swap_register_jprobe(struct jprobe *p);
273 void swap_unregister_jprobe(struct jprobe *p);
274 void swap_jprobe_return(void);
277 int swap_register_kretprobe(struct kretprobe *rp);
278 void swap_unregister_kretprobe(struct kretprobe *rp);
279 void swap_unregister_kretprobes(struct kretprobe **rpp, size_t size);
283 * swap_unregister_kretprobe[s]_top();
284 * synchronize_sched();
285 * swap_unregister_kretprobe[s]_bottom();
287 * rp_disarm - indicates the need for restoration of the return address
289 void swap_unregister_kretprobe_top(struct kretprobe *rp, int rp_disarm);
290 void swap_unregister_kretprobes_top(struct kretprobe **rps, size_t size,
292 void swap_unregister_kretprobe_bottom(struct kretprobe *rp);
293 void swap_unregister_kretprobes_bottom(struct kretprobe **rps, size_t size);
296 int swap_disarm_urp_inst_for_task(struct task_struct *parent, struct task_struct *task);
298 int trampoline_probe_handler (struct kprobe *p, struct pt_regs *regs);
301 DECLARE_PER_CPU(struct kprobe *, swap_current_kprobe);
302 extern atomic_t kprobe_count;
303 extern unsigned long sched_addr;
305 struct kprobe *swap_kprobe_running(void);
306 void swap_reset_current_kprobe(void);
307 struct kprobe_ctlblk *swap_get_kprobe_ctlblk(void);
309 void prepare_singlestep(struct kprobe *p, struct pt_regs *regs);
311 #endif /* _SWAP_KPROBES_H */