--- /dev/null
+// Sleeping locks
+
+#include "types.h"
+#include "defs.h"
+#include "param.h"
+#include "x86.h"
+#include "memlayout.h"
+#include "mmu.h"
+#include "proc.h"
+#include "spinlock.h"
+#include "sleeplock.h"
+
+void
+initsleeplock(struct sleeplock *lk, char *name)
+{
+ initlock(&lk->lk, "sleep lock");
+ lk->name = name;
+ lk->locked = 0;
+ lk->pid = 0;
+}
+
+void
+acquiresleep(struct sleeplock *lk)
+{
+ acquire(&lk->lk);
+ while (lk->locked) {
+ sleep(lk, &lk->lk);
+ }
+ lk->locked = 1;
+ lk->pid = proc->pid;
+ release(&lk->lk);
+}
+
+void
+releasesleep(struct sleeplock *lk)
+{
+ acquire(&lk->lk);
+ lk->locked = 0;
+ lk->pid = 0;
+ wakeup(lk);
+ release(&lk->lk);
+}
+
+int
+holdingsleep(struct sleeplock *lk)
+{
+ int r;
+
+ acquire(&lk->lk);
+ r = lk->locked;
+ release(&lk->lk);
+ return r;
+}
+
+
+
--- /dev/null
+// Long-term locks for processes
+struct sleeplock {
+ uint locked; // Is the lock held?
+ struct spinlock lk; // spinlock protecting this sleep lock
+
+ // For debugging:
+ char *name; // Name of lock.
+ int pid; // Process holding lock
+};
+