check_kunmap.c

   1 /*
   2  * Copyright (C) 2010 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 #include "smatch.h"
  19 #include "smatch_slist.h"
  20
  21 STATE(no_unmap);
  22
  23 static int my_id;
  24
  25 static void check_assignment(void *data)
  26 {
  27         struct expression *expr = (struct expression *)data;
  28         char *fn;
  29
  30         if (!expr)
  31                 return;
  32         if (expr->type != EXPR_CALL)
  33                 return;
  34         fn = expr_to_var(expr->fn);
  35         if (!fn)
  36                 return;
  37         if (!strcmp(fn, "kmap"))
  38                 sm_warning("passing the wrong variable to kunmap()");
  39         free_string(fn);
  40 }
  41
  42 static void match_kmap_atomic(const char *fn, struct expression *expr, void *data)
  43 {
  44         struct expression *arg;
  45
  46         arg = get_argument_from_call_expr(expr->args, 0);
  47         set_state_expr(my_id, arg, &no_unmap);
  48 }
  49
  50 static void match_kunmap_atomic(const char *fn, struct expression *expr, void *data)
  51 {
  52         struct expression *arg;
  53         struct sm_state *sm;
  54
  55         arg = get_argument_from_call_expr(expr->args, 0);
  56         sm = get_sm_state_expr(my_id, arg);
  57         if (!sm)
  58                 return;
  59         if (slist_has_state(sm->possible, &no_unmap))
  60                 sm_warning("passing the wrong variable to kmap_atomic()");
  61 }
  62
  63 static void match_kunmap(const char *fn, struct expression *expr, void *data)
  64 {
  65         struct expression *arg;
  66         struct sm_state *sm;
  67         struct sm_state *tmp;
  68
  69         arg = get_argument_from_call_expr(expr->args, 0);
  70         sm = get_sm_state_expr(check_assigned_expr_id, arg);
  71         if (!sm)
  72                 return;
  73         FOR_EACH_PTR(sm->possible, tmp) {
  74                 check_assignment(tmp->state->data);
  75         } END_FOR_EACH_PTR(tmp);
  76 }
  77
  78 void check_kunmap(int id)
  79 {
  80         my_id = id;
  81         if (option_project != PROJ_KERNEL)
  82                 return;
  83         add_function_hook("kunmap", &match_kunmap, NULL);
  84         add_function_hook("kmap_atomic", &match_kmap_atomic, NULL);
  85         add_function_hook("kunmap_atomic", &match_kunmap_atomic, NULL);
  86 }