1 files changed, 55 insertions, 0 deletions
diff --git a/kernel/sleeplock.c b/kernel/sleeplock.c
new file mode 100644
index 0000000..b490370
--- /dev/null
+++ b/kernel/sleeplock.c
@@ -0,0 +1,55 @@
+// Sleeping locks
+
+#include "types.h"
+#include "riscv.h"
+#include "defs.h"
+#include "param.h"
+#include "memlayout.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 = myproc()->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 && (lk->pid == myproc()->pid);
+  release(&lk->lk);
+  return r;
+}
+
+
+