1 files changed, 57 insertions, 0 deletions
diff --git a/machine/htif.c b/machine/htif.c
index fa3db53..18457d6 100644
--- a/machine/htif.c
+++ b/machine/htif.c
@@ -2,6 +2,8 @@
 #include "atomic.h"
 #include "mtrap.h"
 
+#include <string.h>
+
 volatile uint64_t tohost __attribute__((section(".htif")));
 volatile uint64_t fromhost __attribute__((section(".htif")));
 volatile int htif_console_buf;
@@ -85,3 +87,58 @@ void htif_poweroff()
     tohost = 1;
   }
 }
+
+struct request {
+  uint64_t addr;
+  uint64_t offset;
+  uint64_t size;
+  uint64_t tag;
+};
+
+void htif_disk_read(uintptr_t addr, uintptr_t offset, size_t size)
+{
+  struct request req;
+
+  req.addr = addr;
+  req.offset = offset;
+  req.size = size;
+  req.tag = 0;
+
+  do_tohost_fromhost(2, 0, (uintptr_t) &req);
+}
+
+void htif_disk_write(uintptr_t addr, uintptr_t offset, size_t size)
+{
+  struct request req;
+
+  req.addr = addr;
+  req.offset = offset;
+  req.size = size;
+  req.tag = 0;
+
+  do_tohost_fromhost(2, 1, (uintptr_t) &req);
+}
+
+unsigned long htif_disk_size(void)
+{
+  char idbuf[128];
+  uintptr_t addr = (uintptr_t) idbuf;
+  unsigned long payload;
+  char *id = idbuf, *s;
+
+  // The buffer address needs to be aligned to 64 bytes
+  if (addr % 64 != 0) {
+    unsigned long inc = 64 - (addr % 64);
+    addr += inc;
+    id += inc;
+  }
+
+  payload = (addr << 8) | 0xff;
+  do_tohost_fromhost(2, 255, payload);
+
+  s = strstr(id, "size=");
+  if (s == NULL)
+    return 0;
+  s += 5;
+  return atol(s);
+}