1 /* 2 * Copyright (C) 2015 Oracle. 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 #include "smatch_extra.h" 21 22 static int my_id; 23 24 STATE(positive); 25 STATE(ok); 26 27 static void ok_to_use(struct sm_state *sm, struct expression *mod_expr) 28 { 29 if (sm->state != &ok) 30 set_state(my_id, sm->name, sm->sym, &ok); 31 } 32 33 static void match_assign(const char *fn, struct expression *expr, void *unused) 34 { 35 struct range_list *rl; 36 37 if (!get_implied_rl(expr->right, &rl)) 38 return; 39 if (rl_max(rl).value != 1) 40 return; 41 set_state_expr(my_id, expr->left, &positive); 42 } 43 44 static void match_condition(struct expression *expr) 45 { 46 if (!get_state_expr(my_id, expr)) 47 return; 48 /* If the variable is zero that's ok */ 49 set_true_false_states_expr(my_id, expr, NULL, &ok); 50 } 51 52 static void match_return(struct expression *ret_value) 53 { 54 struct smatch_state *state; 55 struct sm_state *sm; 56 sval_t min; 57 58 sm = get_sm_state_expr(my_id, ret_value); 59 if (!sm) 60 return; 61 if (!slist_has_state(sm->possible, &positive)) 62 return; 63 state = get_state_expr(SMATCH_EXTRA, ret_value); 64 if (!state) 65 return; 66 if (!get_absolute_min(ret_value, &min)) 67 return; 68 if (min.value == 0) 69 return; 70 sm_warning("dma_mapping_error() doesn't return an error code"); 71 } 72 73 void check_dma_mapping_error(int id) 74 { 75 if (option_project != PROJ_KERNEL) 76 return; 77 78 my_id = id; 79 add_function_assign_hook("dma_mapping_error", &match_assign, NULL); 80 add_function_assign_hook("pci_dma_mapping_error", &match_assign, NULL); 81 add_hook(&match_condition, CONDITION_HOOK); 82 add_hook(&match_return, RETURN_HOOK); 83 add_modification_hook(my_id, &ok_to_use); 84 }