- switch(new_bit) {
- case LOCK_USED_IN_HARDIRQ:
- if (!valid_state(curr, this, new_bit, LOCK_ENABLED_HARDIRQS))
- return 0;
- if (!valid_state(curr, this, new_bit,
- LOCK_ENABLED_HARDIRQS_READ))
- return 0;
- /*
- * just marked it hardirq-safe, check that this lock
- * took no hardirq-unsafe lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_HARDIRQS, "hard"))
- return 0;
-#if STRICT_READ_CHECKS
- /*
- * just marked it hardirq-safe, check that this lock
- * took no hardirq-unsafe-read lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_HARDIRQS_READ, "hard-read"))
- return 0;
-#endif
- if (hardirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_USED_IN_SOFTIRQ:
- if (!valid_state(curr, this, new_bit, LOCK_ENABLED_SOFTIRQS))
- return 0;
- if (!valid_state(curr, this, new_bit,
- LOCK_ENABLED_SOFTIRQS_READ))
- return 0;
- /*
- * just marked it softirq-safe, check that this lock
- * took no softirq-unsafe lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_SOFTIRQS, "soft"))
- return 0;
-#if STRICT_READ_CHECKS
- /*
- * just marked it softirq-safe, check that this lock
- * took no softirq-unsafe-read lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_SOFTIRQS_READ, "soft-read"))
- return 0;
-#endif
- if (softirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_USED_IN_HARDIRQ_READ:
- if (!valid_state(curr, this, new_bit, LOCK_ENABLED_HARDIRQS))
- return 0;
- /*
- * just marked it hardirq-read-safe, check that this lock
- * took no hardirq-unsafe lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_HARDIRQS, "hard"))
- return 0;
- if (hardirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_USED_IN_SOFTIRQ_READ:
- if (!valid_state(curr, this, new_bit, LOCK_ENABLED_SOFTIRQS))
- return 0;
- /*
- * just marked it softirq-read-safe, check that this lock
- * took no softirq-unsafe lock in the past:
- */
- if (!check_usage_forwards(curr, this,
- LOCK_ENABLED_SOFTIRQS, "soft"))
- return 0;
- if (softirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_ENABLED_HARDIRQS:
- if (!valid_state(curr, this, new_bit, LOCK_USED_IN_HARDIRQ))
- return 0;
- if (!valid_state(curr, this, new_bit,
- LOCK_USED_IN_HARDIRQ_READ))
- return 0;
- /*
- * just marked it hardirq-unsafe, check that no hardirq-safe
- * lock in the system ever took it in the past:
- */
- if (!check_usage_backwards(curr, this,
- LOCK_USED_IN_HARDIRQ, "hard"))
- return 0;
-#if STRICT_READ_CHECKS
- /*
- * just marked it hardirq-unsafe, check that no
- * hardirq-safe-read lock in the system ever took
- * it in the past:
- */
- if (!check_usage_backwards(curr, this,
- LOCK_USED_IN_HARDIRQ_READ, "hard-read"))
- return 0;
-#endif
- if (hardirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_ENABLED_SOFTIRQS:
- if (!valid_state(curr, this, new_bit, LOCK_USED_IN_SOFTIRQ))
- return 0;
- if (!valid_state(curr, this, new_bit,
- LOCK_USED_IN_SOFTIRQ_READ))
- return 0;
- /*
- * just marked it softirq-unsafe, check that no softirq-safe
- * lock in the system ever took it in the past:
- */
- if (!check_usage_backwards(curr, this,
- LOCK_USED_IN_SOFTIRQ, "soft"))
- return 0;
-#if STRICT_READ_CHECKS
- /*
- * just marked it softirq-unsafe, check that no
- * softirq-safe-read lock in the system ever took
- * it in the past:
- */
- if (!check_usage_backwards(curr, this,
- LOCK_USED_IN_SOFTIRQ_READ, "soft-read"))
- return 0;
-#endif
- if (softirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_ENABLED_HARDIRQS_READ:
- if (!valid_state(curr, this, new_bit, LOCK_USED_IN_HARDIRQ))
- return 0;
-#if STRICT_READ_CHECKS
- /*
- * just marked it hardirq-read-unsafe, check that no
- * hardirq-safe lock in the system ever took it in the past:
- */
- if (!check_usage_backwards(curr, this,
- LOCK_USED_IN_HARDIRQ, "hard"))
- return 0;
-#endif
- if (hardirq_verbose(hlock_class(this)))
- ret = 2;
- break;
- case LOCK_ENABLED_SOFTIRQS_READ:
- if (!valid_state(curr, this, new_bit, LOCK_USED_IN_SOFTIRQ))
+typedef int (*check_usage_f)(struct task_struct *, struct held_lock *,
+ enum lock_usage_bit bit, const char *name);
+
+static int
+mark_lock_irq(struct task_struct *curr, struct held_lock *this, int new_bit)
+{
+ int excl_bit = exclusive_bit(new_bit);
+ int read = new_bit & 1;
+ int dir = new_bit & 2;
+
+ /*
+ * mark USED_IN has to look forwards -- to ensure no dependency
+ * has ENABLED state, which would allow recursion deadlocks.
+ *
+ * mark ENABLED has to look backwards -- to ensure no dependee
+ * has USED_IN state, which, again, would allow recursion deadlocks.
+ */
+ check_usage_f usage = dir ?
+ check_usage_backwards : check_usage_forwards;
+
+ /*
+ * Validate that this particular lock does not have conflicting
+ * usage states.
+ */
+ if (!valid_state(curr, this, new_bit, excl_bit))
+ return 0;
+
+ /*
+ * Validate that the lock dependencies don't have conflicting usage
+ * states.
+ */
+ if ((!read || !dir || STRICT_READ_CHECKS) &&
+ !usage(curr, this, excl_bit, state_name(new_bit)))
+ return 0;
+
+ /*
+ * Check for read in write conflicts
+ */
+ if (!read) {
+ if (!valid_state(curr, this, new_bit, excl_bit + 1))