check_locking.c

   1 /*
   2  * Copyright (C) 2009 Dan Carpenter.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
  16  */
  17
  18 /*
  19  * This test checks that locks are held the same across all returns.
  20  *
  21  * Of course, some functions are designed to only hold the locks on success.
  22  * Oh well... We can rewrite it later if we want.
  23  *
  24  * The list of wine locking functions came from an earlier script written
  25  * by Michael Stefaniuc.
  26  *
  27  */
  28
  29 #include "parse.h"
  30 #include "smatch.h"
  31 #include "smatch_extra.h"
  32 #include "smatch_slist.h"
  33
  34 static int my_id;
  35
  36 static int func_has_transition;
  37
  38 STATE(locked);
  39 STATE(start_state);
  40 STATE(unlocked);
  41 STATE(impossible);
  42
  43 enum action {
  44         LOCK,
  45         UNLOCK,
  46 };
  47
  48 enum return_type {
  49         ret_any,
  50         ret_non_zero,
  51         ret_zero,
  52         ret_negative,
  53         ret_positive,
  54 };
  55
  56 #define RETURN_VAL -1
  57 #define NO_ARG -2
  58
  59 struct lock_info {
  60         const char *function;
  61         enum action action;
  62         const char *name;
  63         int arg;
  64         enum return_type return_type;
  65 };
  66
  67 static struct lock_info wine_lock_table[] = {
  68         {"create_window_handle", LOCK, "create_window_handle", RETURN_VAL, ret_non_zero},
  69         {"WIN_GetPtr", LOCK, "create_window_handle", RETURN_VAL, ret_non_zero},
  70         {"WIN_ReleasePtr", UNLOCK, "create_window_handle", 0, ret_any},
  71         {"EnterCriticalSection", LOCK, "CriticalSection", 0, ret_any},
  72         {"LeaveCriticalSection", UNLOCK, "CriticalSection", 0, ret_any},
  73         {"RtlEnterCriticalSection", LOCK, "RtlCriticalSection", 0, ret_any},
  74         {"RtlLeaveCriticalSection", UNLOCK, "RtlCriticalSection", 0, ret_any},
  75         {"GDI_GetObjPtr", LOCK, "GDI_Get", 0, ret_non_zero},
  76         {"GDI_ReleaseObj", UNLOCK, "GDI_Get", 0, ret_any},
  77         {"LdrLockLoaderLock", LOCK, "LdrLockLoaderLock", 2, ret_any},
  78         {"LdrUnlockLoaderLock", UNLOCK, "LdrLockLoaderLock", 1, ret_any},
  79         {"_lock", LOCK, "_lock", 0, ret_any},
  80         {"_unlock", UNLOCK, "_lock", 0, ret_any},
  81         {"msiobj_lock", LOCK, "msiobj_lock", 0, ret_any},
  82         {"msiobj_unlock", UNLOCK, "msiobj_lock", 0, ret_any},
  83         {"RtlAcquirePebLock", LOCK, "PebLock", NO_ARG, ret_any},
  84         {"RtlReleasePebLock", UNLOCK, "PebLock", NO_ARG, ret_any},
  85         {"server_enter_uninterrupted_section", LOCK, "server_uninterrupted_section", 0, ret_any},
  86         {"server_leave_uninterrupted_section", UNLOCK, "server_uninterrupted_section", 0, ret_any},
  87         {"RtlLockHeap", LOCK, "RtlLockHeap", 0, ret_any},
  88         {"RtlUnlockHeap", UNLOCK, "RtlLockHeap", 0, ret_any},
  89         {"_EnterSysLevel", LOCK, "SysLevel", 0, ret_any},
  90         {"_LeaveSysLevel", UNLOCK, "SysLevel", 0, ret_any},
  91         {"USER_Lock", LOCK, "USER_Lock", NO_ARG, ret_any},
  92         {"USER_Unlock", UNLOCK, "USER_Lock", NO_ARG, ret_any},
  93         {"wine_tsx11_lock", LOCK, "wine_tsx11_lock", NO_ARG, ret_any},
  94         {"wine_tsx11_unlock", UNLOCK, "wine_tsx11_lock", NO_ARG, ret_any},
  95         {"wine_tsx11_lock_ptr", LOCK, "wine_tsx11_lock_ptr", NO_ARG, ret_any},
  96         {"wine_tsx11_unlock_ptr", UNLOCK, "wine_tsx11_lock_ptr", NO_ARG, ret_any},
  97         {"wined3d_mutex_lock", LOCK, "wined3d_mutex_lock", NO_ARG, ret_any},
  98         {"wined3d_mutex_unlock", UNLOCK, "wined3d_mutex_lock", NO_ARG, ret_any},
  99         {"X11DRV_DIB_Lock", LOCK, "X11DRV_DIB_Lock", 0, ret_any},
 100         {"X11DRV_DIB_Unlock", UNLOCK, "X11DRV_DIB_Lock", 0, ret_any},
 101 };
 102
 103 static struct lock_info kernel_lock_table[] = {
 104         {"lock_kernel",   LOCK,   "BKL", NO_ARG, ret_any},
 105         {"unlock_kernel", UNLOCK, "BKL", NO_ARG, ret_any},
 106
 107         {"spin_lock",                  LOCK,   "spin_lock", 0, ret_any},
 108         {"spin_unlock",                UNLOCK, "spin_lock", 0, ret_any},
 109         {"spin_lock_nested",           LOCK,   "spin_lock", 0, ret_any},
 110         {"_spin_lock",                 LOCK,   "spin_lock", 0, ret_any},
 111         {"_spin_unlock",               UNLOCK, "spin_lock", 0, ret_any},
 112         {"_spin_lock_nested",          LOCK,   "spin_lock", 0, ret_any},
 113         {"__spin_lock",                LOCK,   "spin_lock", 0, ret_any},
 114         {"__spin_unlock",              UNLOCK, "spin_lock", 0, ret_any},
 115         {"__spin_lock_nested",         LOCK,   "spin_lock", 0, ret_any},
 116         {"raw_spin_lock",              LOCK,   "spin_lock", 0, ret_any},
 117         {"raw_spin_unlock",            UNLOCK, "spin_lock", 0, ret_any},
 118         {"_raw_spin_lock",             LOCK,   "spin_lock", 0, ret_any},
 119         {"_raw_spin_lock_nested",      LOCK,   "spin_lock", 0, ret_any},
 120         {"_raw_spin_unlock",           UNLOCK, "spin_lock", 0, ret_any},
 121         {"__raw_spin_lock",            LOCK,   "spin_lock", 0, ret_any},
 122         {"__raw_spin_unlock",          UNLOCK, "spin_lock", 0, ret_any},
 123
 124         {"spin_lock_irq",              LOCK,   "spin_lock", 0, ret_any},
 125         {"spin_unlock_irq",            UNLOCK, "spin_lock", 0, ret_any},
 126         {"_spin_lock_irq",             LOCK,   "spin_lock", 0, ret_any},
 127         {"_spin_unlock_irq",           UNLOCK, "spin_lock", 0, ret_any},
 128         {"__spin_lock_irq",            LOCK,   "spin_lock", 0, ret_any},
 129         {"__spin_unlock_irq",          UNLOCK, "spin_lock", 0, ret_any},
 130         {"_raw_spin_lock_irq",         LOCK,   "spin_lock", 0, ret_any},
 131         {"_raw_spin_unlock_irq",       UNLOCK, "spin_lock", 0, ret_any},
 132         {"__raw_spin_unlock_irq",      UNLOCK, "spin_lock", 0, ret_any},
 133         {"spin_lock_irqsave",          LOCK,   "spin_lock", 0, ret_any},
 134         {"spin_unlock_irqrestore",     UNLOCK, "spin_lock", 0, ret_any},
 135         {"_spin_lock_irqsave",         LOCK,   "spin_lock", 0, ret_any},
 136         {"_spin_unlock_irqrestore",    UNLOCK, "spin_lock", 0, ret_any},
 137         {"__spin_lock_irqsave",        LOCK,   "spin_lock", 0, ret_any},
 138         {"__spin_unlock_irqrestore",   UNLOCK, "spin_lock", 0, ret_any},
 139         {"_raw_spin_lock_irqsave",     LOCK,   "spin_lock", 0, ret_any},
 140         {"_raw_spin_unlock_irqrestore", UNLOCK, "spin_lock", 0, ret_any},
 141         {"__raw_spin_lock_irqsave",    LOCK,   "spin_lock", 0, ret_any},
 142         {"__raw_spin_unlock_irqrestore", UNLOCK, "spin_lock", 0, ret_any},
 143         {"spin_lock_irqsave_nested",   LOCK,   "spin_lock", 0, ret_any},
 144         {"_spin_lock_irqsave_nested",  LOCK,   "spin_lock", 0, ret_any},
 145         {"__spin_lock_irqsave_nested", LOCK,   "spin_lock", 0, ret_any},
 146         {"_raw_spin_lock_irqsave_nested", LOCK, "spin_lock", 0, ret_any},
 147         {"spin_lock_bh",               LOCK,   "spin_lock", 0, ret_any},
 148         {"spin_unlock_bh",             UNLOCK, "spin_lock", 0, ret_any},
 149         {"_spin_lock_bh",              LOCK,   "spin_lock", 0, ret_any},
 150         {"_spin_unlock_bh",            UNLOCK, "spin_lock", 0, ret_any},
 151         {"__spin_lock_bh",             LOCK,   "spin_lock", 0, ret_any},
 152         {"__spin_unlock_bh",           UNLOCK, "spin_lock", 0, ret_any},
 153
 154         {"spin_trylock",               LOCK,   "spin_lock", 0, ret_non_zero},
 155         {"_spin_trylock",              LOCK,   "spin_lock", 0, ret_non_zero},
 156         {"__spin_trylock",             LOCK,   "spin_lock", 0, ret_non_zero},
 157         {"raw_spin_trylock",           LOCK,   "spin_lock", 0, ret_non_zero},
 158         {"_raw_spin_trylock",          LOCK,   "spin_lock", 0, ret_non_zero},
 159         {"spin_trylock_irq",           LOCK,   "spin_lock", 0, ret_non_zero},
 160         {"spin_trylock_irqsave",       LOCK,   "spin_lock", 0, ret_non_zero},
 161         {"spin_trylock_bh",            LOCK,   "spin_lock", 0, ret_non_zero},
 162         {"_spin_trylock_bh",           LOCK,   "spin_lock", 0, ret_non_zero},
 163         {"__spin_trylock_bh",          LOCK,   "spin_lock", 0, ret_non_zero},
 164         {"__raw_spin_trylock",         LOCK,   "spin_lock", 0, ret_non_zero},
 165         {"_atomic_dec_and_lock",       LOCK,   "spin_lock", 1, ret_non_zero},
 166
 167         {"read_lock",                 LOCK,   "read_lock", 0, ret_any},
 168         {"read_unlock",               UNLOCK, "read_lock", 0, ret_any},
 169         {"_read_lock",                LOCK,   "read_lock", 0, ret_any},
 170         {"_read_unlock",              UNLOCK, "read_lock", 0, ret_any},
 171         {"__read_lock",               LOCK,   "read_lock", 0, ret_any},
 172         {"__read_unlock",             UNLOCK, "read_lock", 0, ret_any},
 173         {"_raw_read_lock",            LOCK,   "read_lock", 0, ret_any},
 174         {"_raw_read_unlock",          UNLOCK, "read_lock", 0, ret_any},
 175         {"__raw_read_lock",           LOCK,   "read_lock", 0, ret_any},
 176         {"__raw_read_unlock",         UNLOCK, "read_lock", 0, ret_any},
 177         {"read_lock_irq",             LOCK,   "read_lock", 0, ret_any},
 178         {"read_unlock_irq" ,          UNLOCK, "read_lock", 0, ret_any},
 179         {"_read_lock_irq",            LOCK,   "read_lock", 0, ret_any},
 180         {"_read_unlock_irq",          UNLOCK, "read_lock", 0, ret_any},
 181         {"__read_lock_irq",           LOCK,   "read_lock", 0, ret_any},
 182         {"__read_unlock_irq",         UNLOCK, "read_lock", 0, ret_any},
 183         {"read_lock_irqsave",         LOCK,   "read_lock", 0, ret_any},
 184         {"read_unlock_irqrestore",    UNLOCK, "read_lock", 0, ret_any},
 185         {"_read_lock_irqsave",        LOCK,   "read_lock", 0, ret_any},
 186         {"_read_unlock_irqrestore",   UNLOCK, "read_lock", 0, ret_any},
 187         {"__read_lock_irqsave",       LOCK,   "read_lock", 0, ret_any},
 188         {"__read_unlock_irqrestore",  UNLOCK, "read_lock", 0, ret_any},
 189         {"read_lock_bh",              LOCK,   "read_lock", 0, ret_any},
 190         {"read_unlock_bh",            UNLOCK, "read_lock", 0, ret_any},
 191         {"_read_lock_bh",             LOCK,   "read_lock", 0, ret_any},
 192         {"_read_unlock_bh",           UNLOCK, "read_lock", 0, ret_any},
 193         {"__read_lock_bh",            LOCK,   "read_lock", 0, ret_any},
 194         {"__read_unlock_bh",          UNLOCK, "read_lock", 0, ret_any},
 195         {"_raw_read_lock_bh",         LOCK,   "read_lock", 0, ret_any},
 196         {"_raw_read_unlock_bh",       UNLOCK, "read_lock", 0, ret_any},
 197         {"__raw_read_lock_bh",        LOCK,   "read_lock", 0, ret_any},
 198         {"__raw_read_unlock_bh",      UNLOCK, "read_lock", 0, ret_any},
 199
 200         {"generic__raw_read_trylock", LOCK,   "read_lock", 0, ret_non_zero},
 201         {"read_trylock",              LOCK,   "read_lock", 0, ret_non_zero},
 202         {"_read_trylock",             LOCK,   "read_lock", 0, ret_non_zero},
 203         {"raw_read_trylock",          LOCK,   "read_lock", 0, ret_non_zero},
 204         {"_raw_read_trylock",         LOCK,   "read_lock", 0, ret_non_zero},
 205         {"__raw_read_trylock",        LOCK,   "read_lock", 0, ret_non_zero},
 206         {"__read_trylock",            LOCK,   "read_lock", 0, ret_non_zero},
 207
 208         {"write_lock",                LOCK,   "write_lock", 0, ret_any},
 209         {"write_unlock",              UNLOCK, "write_lock", 0, ret_any},
 210         {"_write_lock",               LOCK,   "write_lock", 0, ret_any},
 211         {"_write_unlock",             UNLOCK, "write_lock", 0, ret_any},
 212         {"__write_lock",              LOCK,   "write_lock", 0, ret_any},
 213         {"__write_unlock",            UNLOCK, "write_lock", 0, ret_any},
 214         {"write_lock_irq",            LOCK,   "write_lock", 0, ret_any},
 215         {"write_unlock_irq",          UNLOCK, "write_lock", 0, ret_any},
 216         {"_write_lock_irq",           LOCK,   "write_lock", 0, ret_any},
 217         {"_write_unlock_irq",         UNLOCK, "write_lock", 0, ret_any},
 218         {"__write_lock_irq",          LOCK,   "write_lock", 0, ret_any},
 219         {"__write_unlock_irq",        UNLOCK, "write_lock", 0, ret_any},
 220         {"write_lock_irqsave",        LOCK,   "write_lock", 0, ret_any},
 221         {"write_unlock_irqrestore",   UNLOCK, "write_lock", 0, ret_any},
 222         {"_write_lock_irqsave",       LOCK,   "write_lock", 0, ret_any},
 223         {"_write_unlock_irqrestore",  UNLOCK, "write_lock", 0, ret_any},
 224         {"__write_lock_irqsave",      LOCK,   "write_lock", 0, ret_any},
 225         {"__write_unlock_irqrestore", UNLOCK, "write_lock", 0, ret_any},
 226         {"write_lock_bh",             LOCK,   "write_lock", 0, ret_any},
 227         {"write_unlock_bh",           UNLOCK, "write_lock", 0, ret_any},
 228         {"_write_lock_bh",            LOCK,   "write_lock", 0, ret_any},
 229         {"_write_unlock_bh",          UNLOCK, "write_lock", 0, ret_any},
 230         {"__write_lock_bh",           LOCK,   "write_lock", 0, ret_any},
 231         {"__write_unlock_bh",         UNLOCK, "write_lock", 0, ret_any},
 232         {"_raw_write_lock",           LOCK,   "write_lock", 0, ret_any},
 233         {"__raw_write_lock",          LOCK,   "write_lock", 0, ret_any},
 234         {"_raw_write_unlock",         UNLOCK, "write_lock", 0, ret_any},
 235         {"__raw_write_unlock",        UNLOCK, "write_lock", 0, ret_any},
 236
 237         {"write_trylock",             LOCK,   "write_lock", 0, ret_non_zero},
 238         {"_write_trylock",            LOCK,   "write_lock", 0, ret_non_zero},
 239         {"raw_write_trylock",         LOCK,   "write_lock", 0, ret_non_zero},
 240         {"_raw_write_trylock",        LOCK,   "write_lock", 0, ret_non_zero},
 241         {"__write_trylock",           LOCK,   "write_lock", 0, ret_non_zero},
 242         {"__raw_write_trylock",       LOCK,   "write_lock", 0, ret_non_zero},
 243
 244         {"down",               LOCK,   "sem", 0, ret_any},
 245         {"up",                 UNLOCK, "sem", 0, ret_any},
 246         {"down_trylock",       LOCK,   "sem", 0, ret_zero},
 247         {"down_timeout",       LOCK,   "sem", 0, ret_zero},
 248         {"down_interruptible", LOCK,   "sem", 0, ret_zero},
 249
 250         {"mutex_lock",                      LOCK,   "mutex", 0, ret_any},
 251         {"mutex_unlock",                    UNLOCK, "mutex", 0, ret_any},
 252         {"mutex_lock_nested",               LOCK,   "mutex", 0, ret_any},
 253
 254         {"mutex_lock_interruptible",        LOCK,   "mutex", 0, ret_zero},
 255         {"mutex_lock_interruptible_nested", LOCK,   "mutex", 0, ret_zero},
 256         {"mutex_lock_killable",             LOCK,   "mutex", 0, ret_zero},
 257         {"mutex_lock_killable_nested",      LOCK,   "mutex", 0, ret_zero},
 258
 259         {"mutex_trylock",                   LOCK,   "mutex", 0, ret_non_zero},
 260
 261         {"raw_local_irq_disable", LOCK,   "irq", NO_ARG, ret_any},
 262         {"raw_local_irq_enable",  UNLOCK, "irq", NO_ARG, ret_any},
 263         {"spin_lock_irq",         LOCK,   "irq", NO_ARG, ret_any},
 264         {"spin_unlock_irq",       UNLOCK, "irq", NO_ARG, ret_any},
 265         {"_spin_lock_irq",        LOCK,   "irq", NO_ARG, ret_any},
 266         {"_spin_unlock_irq",      UNLOCK, "irq", NO_ARG, ret_any},
 267         {"__spin_lock_irq",       LOCK,   "irq", NO_ARG, ret_any},
 268         {"__spin_unlock_irq",     UNLOCK, "irq", NO_ARG, ret_any},
 269         {"_raw_spin_lock_irq",    LOCK,   "irq", NO_ARG, ret_any},
 270         {"_raw_spin_unlock_irq",  UNLOCK, "irq", NO_ARG, ret_any},
 271         {"__raw_spin_unlock_irq", UNLOCK, "irq", NO_ARG, ret_any},
 272         {"spin_trylock_irq",      LOCK,   "irq", NO_ARG, ret_non_zero},
 273         {"read_lock_irq",         LOCK,   "irq", NO_ARG, ret_any},
 274         {"read_unlock_irq",       UNLOCK, "irq", NO_ARG, ret_any},
 275         {"_read_lock_irq",        LOCK,   "irq", NO_ARG, ret_any},
 276         {"_read_unlock_irq",      UNLOCK, "irq", NO_ARG, ret_any},
 277         {"__read_lock_irq",       LOCK,   "irq", NO_ARG, ret_any},
 278         {"__read_unlock_irq",     UNLOCK, "irq", NO_ARG, ret_any},
 279         {"write_lock_irq",        LOCK,   "irq", NO_ARG, ret_any},
 280         {"write_unlock_irq",      UNLOCK, "irq", NO_ARG, ret_any},
 281         {"_write_lock_irq",       LOCK,   "irq", NO_ARG, ret_any},
 282         {"_write_unlock_irq",     UNLOCK, "irq", NO_ARG, ret_any},
 283         {"__write_lock_irq",      LOCK,   "irq", NO_ARG, ret_any},
 284         {"__write_unlock_irq",    UNLOCK, "irq", NO_ARG, ret_any},
 285
 286         {"arch_local_irq_save",        LOCK,   "irqsave", RETURN_VAL, ret_any},
 287         {"arch_local_irq_restore",     UNLOCK, "irqsave", 0, ret_any},
 288         {"__raw_local_irq_save",       LOCK,   "irqsave", RETURN_VAL, ret_any},
 289         {"raw_local_irq_restore",      UNLOCK, "irqsave", 0, ret_any},
 290         {"spin_lock_irqsave_nested",   LOCK,   "irqsave", RETURN_VAL, ret_any},
 291         {"spin_lock_irqsave",          LOCK,   "irqsave", RETURN_VAL, ret_any},
 292         {"spin_lock_irqsave",          LOCK,   "irqsave", 1, ret_any},
 293         {"spin_unlock_irqrestore",     UNLOCK, "irqsave", 1, ret_any},
 294         {"_spin_lock_irqsave_nested",  LOCK,   "irqsave", RETURN_VAL, ret_any},
 295         {"_spin_lock_irqsave",         LOCK,   "irqsave", RETURN_VAL, ret_any},
 296         {"_spin_lock_irqsave",         LOCK,   "irqsave", 1, ret_any},
 297         {"_spin_unlock_irqrestore",    UNLOCK, "irqsave", 1, ret_any},
 298         {"__spin_lock_irqsave_nested", LOCK,   "irqsave", 1, ret_any},
 299         {"__spin_lock_irqsave",        LOCK,   "irqsave", 1, ret_any},
 300         {"__spin_unlock_irqrestore",   UNLOCK, "irqsave", 1, ret_any},
 301         {"_raw_spin_lock_irqsave",     LOCK,   "irqsave", RETURN_VAL, ret_any},
 302         {"_raw_spin_lock_irqsave",     LOCK,   "irqsave", 1, ret_any},
 303         {"_raw_spin_unlock_irqrestore",UNLOCK, "irqsave", 1, ret_any},
 304         {"__raw_spin_lock_irqsave",    LOCK,   "irqsave", RETURN_VAL, ret_any},
 305         {"__raw_spin_unlock_irqrestore",UNLOCK, "irqsave", 1, ret_any},
 306         {"_raw_spin_lock_irqsave_nested", LOCK, "irqsave", RETURN_VAL, ret_any},
 307         {"spin_trylock_irqsave",       LOCK,   "irqsave", 1, ret_non_zero},
 308         {"read_lock_irqsave",          LOCK,   "irqsave", RETURN_VAL, ret_any},
 309         {"read_lock_irqsave",          LOCK,   "irqsave", 1, ret_any},
 310         {"read_unlock_irqrestore",     UNLOCK, "irqsave", 1, ret_any},
 311         {"_read_lock_irqsave",         LOCK,   "irqsave", RETURN_VAL, ret_any},
 312         {"_read_lock_irqsave",         LOCK,   "irqsave", 1, ret_any},
 313         {"_read_unlock_irqrestore",    UNLOCK, "irqsave", 1, ret_any},
 314         {"__read_lock_irqsave",        LOCK,   "irqsave", RETURN_VAL, ret_any},
 315         {"__read_unlock_irqrestore",   UNLOCK, "irqsave", 1, ret_any},
 316         {"write_lock_irqsave",         LOCK,   "irqsave", RETURN_VAL, ret_any},
 317         {"write_lock_irqsave",         LOCK,   "irqsave", 1, ret_any},
 318         {"write_unlock_irqrestore",    UNLOCK, "irqsave", 1, ret_any},
 319         {"_write_lock_irqsave",        LOCK,   "irqsave", RETURN_VAL, ret_any},
 320         {"_write_lock_irqsave",        LOCK,   "irqsave", 1, ret_any},
 321         {"_write_unlock_irqrestore",   UNLOCK, "irqsave", 1, ret_any},
 322         {"__write_lock_irqsave",       LOCK,   "irqsave", RETURN_VAL, ret_any},
 323         {"__write_unlock_irqrestore",  UNLOCK, "irqsave", 1, ret_any},
 324
 325         {"local_bh_disable",    LOCK,   "bottom_half", NO_ARG, ret_any},
 326         {"_local_bh_disable",   LOCK,   "bottom_half", NO_ARG, ret_any},
 327         {"__local_bh_disable",  LOCK,   "bottom_half", NO_ARG, ret_any},
 328         {"local_bh_enable",     UNLOCK, "bottom_half", NO_ARG, ret_any},
 329         {"_local_bh_enable",    UNLOCK, "bottom_half", NO_ARG, ret_any},
 330         {"__local_bh_enable",   UNLOCK, "bottom_half", NO_ARG, ret_any},
 331         {"spin_lock_bh",        LOCK,   "bottom_half", NO_ARG, ret_any},
 332         {"spin_unlock_bh",      UNLOCK, "bottom_half", NO_ARG, ret_any},
 333         {"_spin_lock_bh",       LOCK,   "bottom_half", NO_ARG, ret_any},
 334         {"_spin_unlock_bh",     UNLOCK, "bottom_half", NO_ARG, ret_any},
 335         {"__spin_lock_bh",      LOCK,   "bottom_half", NO_ARG, ret_any},
 336         {"__spin_unlock_bh",    UNLOCK, "bottom_half", NO_ARG, ret_any},
 337         {"read_lock_bh",        LOCK,   "bottom_half", NO_ARG, ret_any},
 338         {"read_unlock_bh",      UNLOCK, "bottom_half", NO_ARG, ret_any},
 339         {"_read_lock_bh",       LOCK,   "bottom_half", NO_ARG, ret_any},
 340         {"_read_unlock_bh",     UNLOCK, "bottom_half", NO_ARG, ret_any},
 341         {"__read_lock_bh",      LOCK,   "bottom_half", NO_ARG, ret_any},
 342         {"__read_unlock_bh",    UNLOCK, "bottom_half", NO_ARG, ret_any},
 343         {"_raw_read_lock_bh",   LOCK,   "bottom_half", NO_ARG, ret_any},
 344         {"_raw_read_unlock_bh", UNLOCK, "bottom_half", NO_ARG, ret_any},
 345         {"write_lock_bh",       LOCK,   "bottom_half", NO_ARG, ret_any},
 346         {"write_unlock_bh",     UNLOCK, "bottom_half", NO_ARG, ret_any},
 347         {"_write_lock_bh",      LOCK,   "bottom_half", NO_ARG, ret_any},
 348         {"_write_unlock_bh",    UNLOCK, "bottom_half", NO_ARG, ret_any},
 349         {"__write_lock_bh",     LOCK,   "bottom_half", NO_ARG, ret_any},
 350         {"__write_unlock_bh",   UNLOCK, "bottom_half", NO_ARG, ret_any},
 351         {"spin_trylock_bh",     LOCK,   "bottom_half", NO_ARG, ret_non_zero},
 352         {"_spin_trylock_bh",    LOCK,   "bottom_half", NO_ARG, ret_non_zero},
 353         {"__spin_trylock_bh",   LOCK,   "bottom_half", NO_ARG, ret_non_zero},
 354
 355         {"ffs_mutex_lock",        LOCK,   "mutex", 0, ret_zero},
 356 };
 357
 358 static struct lock_info *lock_table;
 359
 360 static struct tracker_list *starts_locked;
 361 static struct tracker_list *starts_unlocked;
 362
 363 struct locks_on_return {
 364         int line;
 365         struct tracker_list *locked;
 366         struct tracker_list *unlocked;
 367         struct range_list *return_values;
 368 };
 369 DECLARE_PTR_LIST(return_list, struct locks_on_return);
 370 static struct return_list *all_returns;
 371
 372 static char *make_full_name(const char *lock, const char *var)
 373 {
 374         static char tmp_buf[512];
 375
 376         snprintf(tmp_buf, sizeof(tmp_buf), "%s:%s", lock, var);
 377         remove_parens(tmp_buf);
 378         return alloc_string(tmp_buf);
 379 }
 380
 381 static struct expression *remove_spinlock_check(struct expression *expr)
 382 {
 383         if (expr->type != EXPR_CALL)
 384                 return expr;
 385         if (expr->fn->type != EXPR_SYMBOL)
 386                 return expr;
 387         if (strcmp(expr->fn->symbol_name->name, "spinlock_check"))
 388                 return expr;
 389         expr = get_argument_from_call_expr(expr->args, 0);
 390         return expr;
 391 }
 392
 393 static char *get_full_name(struct expression *expr, int index)
 394 {
 395         struct expression *arg;
 396         char *name = NULL;
 397         char *full_name = NULL;
 398         struct lock_info *lock = &lock_table[index];
 399
 400         if (lock->arg == RETURN_VAL) {
 401                 name = expr_to_var(expr->left);
 402                 full_name = make_full_name(lock->name, name);
 403         } else if (lock->arg == NO_ARG) {
 404                 full_name = make_full_name(lock->name, "");
 405         } else {
 406                 arg = get_argument_from_call_expr(expr->args, lock->arg);
 407                 if (!arg)
 408                         goto free;
 409                 arg = remove_spinlock_check(arg);
 410                 name = expr_to_str(arg);
 411                 if (!name)
 412                         goto free;
 413                 full_name = make_full_name(lock->name, name);
 414         }
 415 free:
 416         free_string(name);
 417         return full_name;
 418 }
 419
 420 static struct smatch_state *get_start_state(struct sm_state *sm)
 421 {
 422         int is_locked = 0;
 423         int is_unlocked = 0;
 424
 425         if (in_tracker_list(starts_locked, my_id, sm->name, sm->sym))
 426                 is_locked = 1;
 427         if (in_tracker_list(starts_unlocked, my_id, sm->name, sm->sym))
 428                 is_unlocked = 1;
 429         if (is_locked && is_unlocked)
 430                 return &undefined;
 431         if (is_locked)
 432                 return &locked;
 433         if (is_unlocked)
 434                 return &unlocked;
 435         return &undefined;
 436 }
 437
 438 static struct smatch_state *unmatched_state(struct sm_state *sm)
 439 {
 440         return &start_state;
 441 }
 442
 443 static void pre_merge_hook(struct sm_state *sm)
 444 {
 445         if (is_impossible_path())
 446                 set_state(my_id, sm->name, sm->sym, &impossible);
 447 }
 448
 449 static void do_lock(const char *name)
 450 {
 451         struct sm_state *sm;
 452
 453         if (__inline_fn)
 454                 return;
 455
 456         sm = get_sm_state(my_id, name, NULL);
 457         if (!sm)
 458                 add_tracker(&starts_unlocked, my_id, name, NULL);
 459         if (sm && slist_has_state(sm->possible, &locked) &&
 460                         strcmp(name, "bottom_half:") != 0)
 461                 sm_msg("error: double lock '%s'", name);
 462         if (sm)
 463                 func_has_transition = TRUE;
 464         set_state(my_id, name, NULL, &locked);
 465 }
 466
 467 static void do_lock_failed(const char *name)
 468 {
 469         struct sm_state *sm;
 470
 471         if (__inline_fn)
 472                 return;
 473
 474         sm = get_sm_state(my_id, name, NULL);
 475         if (!sm)
 476                 add_tracker(&starts_unlocked, my_id, name, NULL);
 477         set_state(my_id, name, NULL, &unlocked);
 478 }
 479
 480 static void do_unlock(const char *name)
 481 {
 482         struct sm_state *sm;
 483
 484         if (__inline_fn)
 485                 return;
 486         if (__path_is_null())
 487                 return;
 488         sm = get_sm_state(my_id, name, NULL);
 489         if (!sm)
 490                 add_tracker(&starts_locked, my_id, name, NULL);
 491         if (sm && slist_has_state(sm->possible, &unlocked) &&
 492                         strcmp(name, "bottom_half:") != 0)
 493                 sm_msg("error: double unlock '%s'", name);
 494         if (sm)
 495                 func_has_transition = TRUE;
 496         set_state(my_id, name, NULL, &unlocked);
 497 }
 498
 499 static void match_lock_held(const char *fn, struct expression *call_expr,
 500                         struct expression *assign_expr, void *_index)
 501 {
 502         int index = PTR_INT(_index);
 503         char *lock_name;
 504         struct lock_info *lock = &lock_table[index];
 505
 506         if (lock->arg == NO_ARG) {
 507                 lock_name = get_full_name(NULL, index);
 508         } else if (lock->arg == RETURN_VAL) {
 509                 if (!assign_expr)
 510                         return;
 511                 lock_name = get_full_name(assign_expr, index);
 512         } else {
 513                 lock_name = get_full_name(call_expr, index);
 514         }
 515         if (!lock_name)
 516                 return;
 517         do_lock(lock_name);
 518         free_string(lock_name);
 519 }
 520
 521 static void match_lock_failed(const char *fn, struct expression *call_expr,
 522                         struct expression *assign_expr, void *_index)
 523 {
 524         int index = PTR_INT(_index);
 525         char *lock_name;
 526         struct lock_info *lock = &lock_table[index];
 527
 528         if (lock->arg == NO_ARG) {
 529                 lock_name = get_full_name(NULL, index);
 530         } else if (lock->arg == RETURN_VAL) {
 531                 if (!assign_expr)
 532                         return;
 533                 lock_name = get_full_name(assign_expr, index);
 534         } else {
 535                 lock_name = get_full_name(call_expr, index);
 536         }
 537         if (!lock_name)
 538                 return;
 539         do_lock_failed(lock_name);
 540         free_string(lock_name);
 541 }
 542
 543 static void match_returns_locked(const char *fn, struct expression *expr,
 544                                       void *_index)
 545 {
 546         char *full_name = NULL;
 547         int index = PTR_INT(_index);
 548         struct lock_info *lock = &lock_table[index];
 549
 550         if (lock->arg != RETURN_VAL)
 551                 return;
 552         full_name = get_full_name(expr, index);
 553         do_lock(full_name);
 554 }
 555
 556 static void match_lock_unlock(const char *fn, struct expression *expr, void *_index)
 557 {
 558         char *full_name = NULL;
 559         int index = PTR_INT(_index);
 560         struct lock_info *lock = &lock_table[index];
 561
 562         if (__inline_fn)
 563                 return;
 564
 565         full_name = get_full_name(expr, index);
 566         if (!full_name)
 567                 return;
 568         if (lock->action == LOCK)
 569                 do_lock(full_name);
 570         else
 571                 do_unlock(full_name);
 572         free_string(full_name);
 573 }
 574
 575 static struct locks_on_return *alloc_return(struct expression *expr)
 576 {
 577         struct locks_on_return *ret;
 578
 579         ret = malloc(sizeof(*ret));
 580         if (!get_implied_rl(expr, &ret->return_values))
 581                 ret->return_values = NULL;
 582         ret->line = get_lineno();
 583         ret->locked = NULL;
 584         ret->unlocked = NULL;
 585         return ret;
 586 }
 587
 588 static int check_possible(struct sm_state *sm)
 589 {
 590         struct sm_state *tmp;
 591         int islocked = 0;
 592         int isunlocked = 0;
 593         int undef = 0;
 594
 595         if (!option_spammy)
 596                 return 0;
 597
 598         FOR_EACH_PTR(sm->possible, tmp) {
 599                 if (tmp->state == &locked)
 600                         islocked = 1;
 601                 if (tmp->state == &unlocked)
 602                         isunlocked = 1;
 603                 if (tmp->state == &start_state) {
 604                         struct smatch_state *s;
 605
 606                         s = get_start_state(tmp);
 607                         if (s == &locked)
 608                                 islocked = 1;
 609                         else if (s == &unlocked)
 610                                 isunlocked = 1;
 611                         else
 612                                 undef = 1;
 613                 }
 614                 if (tmp->state == &undefined)
 615                         undef = 1;  // i don't think this is possible any more.
 616         } END_FOR_EACH_PTR(tmp);
 617         if ((islocked && isunlocked) || undef) {
 618                 sm_msg("warn: '%s' is sometimes locked here and sometimes unlocked.", sm->name);
 619                 return 1;
 620         }
 621         return 0;
 622 }
 623
 624 static struct position warned_pos;
 625
 626 static void match_return(int return_id, char *return_ranges, struct expression *expr)
 627 {
 628         struct locks_on_return *ret;
 629         struct stree *stree;
 630         struct sm_state *tmp;
 631
 632         if (!final_pass)
 633                 return;
 634         if (__inline_fn)
 635                 return;
 636
 637         if (expr && cmp_pos(expr->pos, warned_pos) == 0)
 638                 return;
 639
 640         ret = alloc_return(expr);
 641
 642         stree = __get_cur_stree();
 643         FOR_EACH_MY_SM(my_id, stree, tmp) {
 644                 if (tmp->state == &locked) {
 645                         add_tracker(&ret->locked, tmp->owner, tmp->name,
 646                                 tmp->sym);
 647                 } else if (tmp->state == &unlocked) {
 648                         add_tracker(&ret->unlocked, tmp->owner, tmp->name,
 649                                 tmp->sym);
 650                 } else if (tmp->state == &start_state) {
 651                         struct smatch_state *s;
 652
 653                         s = get_start_state(tmp);
 654                         if (s == &locked)
 655                                 add_tracker(&ret->locked, tmp->owner, tmp->name,
 656                                             tmp->sym);
 657                         if (s == &unlocked)
 658                                 add_tracker(&ret->unlocked, tmp->owner,tmp->name,
 659                                              tmp->sym);
 660                 } else {
 661                         if (check_possible(tmp)) {
 662                                 if (expr)
 663                                         warned_pos = expr->pos;
 664                         }
 665                 }
 666         } END_FOR_EACH_SM(tmp);
 667         add_ptr_list(&all_returns, ret);
 668 }
 669
 670 static void add_line(struct range_list **rl, int line)
 671 {
 672         sval_t sval = sval_type_val(&int_ctype, line);
 673
 674         add_range(rl, sval, sval);
 675 }
 676
 677 static int line_printed(struct range_list *rl, int line)
 678 {
 679         sval_t sval = sval_type_val(&int_ctype, line);
 680
 681         return rl_has_sval(rl, sval);
 682 }
 683
 684 static void print_inconsistent_returns(struct tracker *lock,
 685                                 struct smatch_state *start)
 686 {
 687         struct locks_on_return *tmp;
 688         struct range_list *printed = NULL;
 689         int i;
 690
 691         sm_msg("warn: inconsistent returns '%s'.", lock->name);
 692         sm_printf("  Locked on:   ");
 693
 694         i = 0;
 695         FOR_EACH_PTR(all_returns, tmp) {
 696                 if (line_printed(printed, tmp->line))
 697                         continue;
 698                 if (in_tracker_list(tmp->unlocked, lock->owner, lock->name, lock->sym))
 699                         continue;
 700                 if (in_tracker_list(tmp->locked, lock->owner, lock->name, lock->sym)) {
 701                         if (i++)
 702                                 sm_printf("               ");
 703                         sm_printf("line %d\n", tmp->line);
 704                         add_line(&printed, tmp->line);
 705                         continue;
 706                 }
 707                 if (start == &locked) {
 708                         if (i++)
 709                                 sm_printf("               ");
 710                         sm_printf("line %d\n", tmp->line);
 711                         add_line(&printed, tmp->line);
 712                 }
 713         } END_FOR_EACH_PTR(tmp);
 714
 715         sm_printf("  Unlocked on: ");
 716         printed = NULL;
 717         i = 0;
 718         FOR_EACH_PTR(all_returns, tmp) {
 719                 if (line_printed(printed, tmp->line))
 720                         continue;
 721                 if (in_tracker_list(tmp->unlocked, lock->owner, lock->name, lock->sym)) {
 722                         if (i++)
 723                                 sm_printf("               ");
 724                         sm_printf("line %d\n", tmp->line);
 725                         add_line(&printed, tmp->line);
 726                         continue;
 727                 }
 728                 if (in_tracker_list(tmp->locked, lock->owner, lock->name, lock->sym))
 729                         continue;
 730                 if (start == &unlocked) {
 731                         if (i++)
 732                                 sm_printf("               ");
 733                         sm_printf("line %d\n", tmp->line);
 734                         add_line(&printed, tmp->line);
 735                 }
 736         } END_FOR_EACH_PTR(tmp);
 737 }
 738
 739 static int matches_return_type(struct range_list *rl, enum return_type type)
 740 {
 741         sval_t zero_sval = ll_to_sval(0);
 742
 743         /* All these double negatives are super ugly!  */
 744
 745         switch (type) {
 746         case ret_zero:
 747                 return !possibly_true_rl(rl, SPECIAL_NOTEQUAL, alloc_rl(zero_sval, zero_sval));
 748         case ret_non_zero:
 749                 return !possibly_true_rl(rl, SPECIAL_EQUAL, alloc_rl(zero_sval, zero_sval));
 750         case ret_negative:
 751                 return !possibly_true_rl(rl, SPECIAL_GTE, alloc_rl(zero_sval, zero_sval));
 752         case ret_positive:
 753                 return !possibly_true_rl(rl, '<', alloc_rl(zero_sval, zero_sval));
 754         case ret_any:
 755         default:
 756                 return 1;
 757         }
 758 }
 759
 760 static int match_held(struct tracker *lock, struct locks_on_return *this_return, struct smatch_state *start)
 761 {
 762         if (in_tracker_list(this_return->unlocked, lock->owner, lock->name, lock->sym))
 763                 return 0;
 764         if (in_tracker_list(this_return->locked, lock->owner, lock->name, lock->sym))
 765                 return 1;
 766         if (start == &unlocked)
 767                 return 0;
 768         return 1;
 769 }
 770
 771 static int match_released(struct tracker *lock, struct locks_on_return *this_return, struct smatch_state *start)
 772 {
 773         if (in_tracker_list(this_return->unlocked, lock->owner, lock->name, lock->sym))
 774                 return 1;
 775         if (in_tracker_list(this_return->locked, lock->owner, lock->name, lock->sym))
 776                 return 0;
 777         if (start == &unlocked)
 778                 return 1;
 779         return 0;
 780 }
 781
 782 static int held_on_return(struct tracker *lock, struct smatch_state *start, enum return_type type)
 783 {
 784         struct locks_on_return *tmp;
 785
 786         FOR_EACH_PTR(all_returns, tmp) {
 787                 if (!matches_return_type(tmp->return_values, type))
 788                         continue;
 789                 if (match_held(lock, tmp, start))
 790                         return 1;
 791         } END_FOR_EACH_PTR(tmp);
 792         return 0;
 793 }
 794
 795 static int released_on_return(struct tracker *lock, struct smatch_state *start, enum return_type type)
 796 {
 797         struct locks_on_return *tmp;
 798
 799         FOR_EACH_PTR(all_returns, tmp) {
 800                 if (!matches_return_type(tmp->return_values, type))
 801                         continue;
 802                 if (match_released(lock, tmp, start))
 803                         return 1;
 804         } END_FOR_EACH_PTR(tmp);
 805         return 0;
 806 }
 807
 808 static void check_returns_consistently(struct tracker *lock,
 809                                 struct smatch_state *start)
 810 {
 811         struct symbol *type;
 812
 813         if (!held_on_return(lock, start, ret_any) ||
 814             !released_on_return(lock, start, ret_any))
 815                 return;
 816
 817         if (held_on_return(lock, start, ret_zero) &&
 818             !held_on_return(lock, start, ret_non_zero))
 819                 return;
 820
 821         if (held_on_return(lock, start, ret_positive) &&
 822             !held_on_return(lock, start, ret_zero))
 823                 return;
 824
 825         if (held_on_return(lock, start, ret_positive) &&
 826             !held_on_return(lock, start, ret_negative))
 827                 return;
 828
 829         type = cur_func_return_type();
 830         if (type && type->type == SYM_PTR) {
 831                 if (held_on_return(lock, start, ret_non_zero) &&
 832                     !held_on_return(lock, start, ret_zero))
 833                         return;
 834         }
 835
 836         print_inconsistent_returns(lock, start);
 837 }
 838
 839 static void check_consistency(struct symbol *sym)
 840 {
 841         struct tracker *tmp;
 842
 843         FOR_EACH_PTR(starts_locked, tmp) {
 844                 if (in_tracker_list(starts_unlocked, tmp->owner, tmp->name,
 845                                         tmp->sym))
 846                         sm_msg("error:  locking inconsistency.  We assume "
 847                                    "'%s' is both locked and unlocked at the "
 848                                    "start.",
 849                                 tmp->name);
 850         } END_FOR_EACH_PTR(tmp);
 851
 852         FOR_EACH_PTR(starts_locked, tmp) {
 853                 check_returns_consistently(tmp, &locked);
 854         } END_FOR_EACH_PTR(tmp);
 855
 856         FOR_EACH_PTR(starts_unlocked, tmp) {
 857                 check_returns_consistently(tmp, &unlocked);
 858         } END_FOR_EACH_PTR(tmp);
 859 }
 860
 861 static void clear_lists(void)
 862 {
 863         struct locks_on_return *tmp;
 864
 865         func_has_transition = FALSE;
 866
 867         free_trackers_and_list(&starts_locked);
 868         free_trackers_and_list(&starts_unlocked);
 869
 870         FOR_EACH_PTR(all_returns, tmp) {
 871                 free_trackers_and_list(&tmp->locked);
 872                 free_trackers_and_list(&tmp->unlocked);
 873                 free(tmp);
 874         } END_FOR_EACH_PTR(tmp);
 875         __free_ptr_list((struct ptr_list **)&all_returns);
 876 }
 877
 878 static void match_func_end(struct symbol *sym)
 879 {
 880         if (__inline_fn)
 881                 return;
 882
 883         if (func_has_transition)
 884                 check_consistency(sym);
 885         clear_lists();
 886 }
 887
 888 static void register_lock(int index)
 889 {
 890         struct lock_info *lock = &lock_table[index];
 891         void *idx = INT_PTR(index);
 892
 893         if (lock->return_type == ret_non_zero) {
 894                 return_implies_state(lock->function, valid_ptr_min, valid_ptr_max, &match_lock_held, idx);
 895                 return_implies_state(lock->function, 0, 0, &match_lock_failed, idx);
 896         } else if (lock->return_type == ret_any && lock->arg == RETURN_VAL) {
 897                 add_function_assign_hook(lock->function, &match_returns_locked, idx);
 898         } else if (lock->return_type == ret_any) {
 899                 add_function_hook(lock->function, &match_lock_unlock, idx);
 900         } else if (lock->return_type == ret_zero) {
 901                 return_implies_state(lock->function, 0, 0, &match_lock_held, idx);
 902                 return_implies_state(lock->function, -4095, -1, &match_lock_failed, idx);
 903         }
 904 }
 905
 906 static void load_table(struct lock_info *_lock_table, int size)
 907 {
 908         int i;
 909
 910         lock_table = _lock_table;
 911
 912         for (i = 0; i < size; i++) {
 913                 if (lock_table[i].action == LOCK)
 914                         register_lock(i);
 915                 else
 916                         add_function_hook(lock_table[i].function, &match_lock_unlock, INT_PTR(i));
 917         }
 918 }
 919
 920 /* print_held_locks() is used in check_call_tree.c */
 921 void print_held_locks(void)
 922 {
 923         struct stree *stree;
 924         struct sm_state *sm;
 925         int i = 0;
 926
 927         stree = __get_cur_stree();
 928         FOR_EACH_MY_SM(my_id, stree, sm) {
 929                 if (sm->state != &locked)
 930                         continue;
 931                 if (i++)
 932                         sm_printf(" ");
 933                 sm_printf("'%s'", sm->name);
 934         } END_FOR_EACH_SM(sm);
 935 }
 936
 937 void check_locking(int id)
 938 {
 939         my_id = id;
 940
 941         if (option_project == PROJ_WINE)
 942                 load_table(wine_lock_table, ARRAY_SIZE(wine_lock_table));
 943         else if (option_project == PROJ_KERNEL)
 944                 load_table(kernel_lock_table, ARRAY_SIZE(kernel_lock_table));
 945         else
 946                 return;
 947
 948         add_unmatched_state_hook(my_id, &unmatched_state);
 949         add_pre_merge_hook(my_id, &pre_merge_hook);
 950         add_split_return_callback(match_return);
 951         add_hook(&match_func_end, END_FUNC_HOOK);
 952 }