Handle reads and writes to T_DEV.

ce3ea511 · Silas Boyd-Wickizer · d00a87f6 · ce3ea511 · ce3ea511 · ce3ea511
--- a/console.c
+++ b/console.c
@@ -7,10 +7,15 @@
 #include "cpu.h"
 #include "kernel.h"
 #include "spinlock.h"
+#include "fs.h"
+#include "condvar.h"
+#include "file.h"
 #include "x86.h"

 #include <stdarg.h>

+#define BACKSPACE 0x100
+
 static struct {
  struct spinlock lock;
  int locking;
@@ -42,12 +47,30 @@ printint(void (*putch) (void*, char), void *putarg,
    putch(putarg, buf[i]);
 }

+static void
+consputc(int c)
+{
+  // XXX(sbw)
+#if 0
+  if(panicked){
+    cli();
+    for(;;)
+      ;
+  }
+#endif
+
+  if(c == BACKSPACE){
+    uartputc('\b'); uartputc(' '); uartputc('\b');
+  } else
+    uartputc(c);
+  cgaputc(c);
+}
+
 // Print to the console.
 static void
 writecons(void *arg, char c)
 {
-  uartputc(c);
-  cgaputc(c);
+  consputc(c);
 }

 // Only understands %d, %u, %x, %s, %lx.
@@ -189,10 +212,34 @@ panic(const char *s)
    ;
 }

+static int
+consolewrite(struct inode *ip, char *buf, int n)
+{
+  int i;
+
+  iunlock(ip);
+  acquire(&cons.lock);
+  for(i = 0; i < n; i++)
+    consputc(buf[i] & 0xff);
+  release(&cons.lock);
+  ilock(ip, 1);
+
+  return n;
+}
+
+static int
+consoleread(struct inode *ip, char *dst, int n)
+{
+  panic("consoleread");
+}
+
 void
 initconsole(void)
 {
  initlock(&cons.lock, "console");
+  devsw[CONSOLE].write = consolewrite;
+  devsw[CONSOLE].read = consoleread;
+
  // XXX(sbw) enable once we setup %gs
  cons.locking = 0;
 }
--- a/file.c
+++ b/file.c
@@ -7,7 +7,7 @@
 #include "file.h"
 #include "stat.h"

-struct devsw __attribute__ ((aligned (CACHELINE))) devsw[NDEV];
+struct devsw __mpalign__ devsw[NDEV];

 // Allocate a file structure.
 struct file*

--- a/fs.c
+++ b/fs.c
@@ -515,13 +515,9 @@ readi(struct inode *ip, char *dst, u32 off, u32 n)
  struct buf *bp;

  if(ip->type == T_DEV){
-    // XXX(sbw)
-    panic("readi T_DEV");
-#if 0
    if(ip->major < 0 || ip->major >= NDEV || !devsw[ip->major].read)
      return -1;
    return devsw[ip->major].read(ip, dst, n);
-#endif
  }

  if(off > ip->size || off + n < off)
@@ -547,13 +543,9 @@ writei(struct inode *ip, char *src, u32 off, u32 n)
  struct buf *bp;

  if(ip->type == T_DEV){
-    // XXX(sbw)
-    panic("writei T_DEV");
-#if 0
    if(ip->major < 0 || ip->major >= NDEV || !devsw[ip->major].write)
      return -1;
    return devsw[ip->major].write(ip, src, n);
-#endif
  }

  if(off > ip->size || off + n < off)