[PATCH v2 07/12] mini-os: use get_file_from_fd() in netfront

[Juergen Gross <jgross@xxxxxxxx>]

Instead of directly accessing the files[] array use get_file_from_fd().

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 include/lib.h |  3 +--
 lib/sys.c     | 23 ------------------
 netfront.c    | 64 ++++++++++++++++++++++++++++++++++++++++++++-------
 3 files changed, 57 insertions(+), 33 deletions(-)

diff --git a/include/lib.h b/include/lib.h
index 05f5083..aa8036e 100644
--- a/include/lib.h
+++ b/include/lib.h
@@ -163,8 +163,7 @@ void sanity_check(void);
 #define FTYPE_SAVEFILE   5
 #define FTYPE_FB         6
 #define FTYPE_KBD        7
-#define FTYPE_TAP        8
-#define FTYPE_N          9
+#define FTYPE_N          8
 #define FTYPE_SPARE     16
 
 typedef int file_read_func(int fd, void *buf, size_t nbytes);
diff --git a/lib/sys.c b/lib/sys.c
index f84fedd..7f2e11f 100644
--- a/lib/sys.c
+++ b/lib/sys.c
@@ -303,17 +303,6 @@ int read(int fd, void *buf, size_t nbytes)
        case FTYPE_SOCKET:
            return lwip_read(files[fd].fd, buf, nbytes);
 #endif
-#ifdef CONFIG_NETFRONT
-       case FTYPE_TAP: {
-           ssize_t ret;
-           ret = netfront_receive(files[fd].dev, buf, nbytes);
-           if (ret <= 0) {
-               errno = EAGAIN;
-               return -1;
-           }
-           return ret;
-       }
-#endif
 #ifdef CONFIG_KBDFRONT
         case FTYPE_KBD: {
             int ret, n;
@@ -369,11 +358,6 @@ int write(int fd, const void *buf, size_t nbytes)
 #ifdef HAVE_LWIP
        case FTYPE_SOCKET:
            return lwip_write(files[fd].fd, (void*) buf, nbytes);
-#endif
-#ifdef CONFIG_NETFRONT
-       case FTYPE_TAP:
-           netfront_xmit(files[fd].dev, (void*) buf, nbytes);
-           return nbytes;
 #endif
        default:
            break;
@@ -459,11 +443,6 @@ int close(int fd)
            res = lwip_close(files[fd].fd);
             break;
 #endif
-#ifdef CONFIG_NETFRONT
-       case FTYPE_TAP:
-           shutdown_netfront(files[fd].dev);
-            break;
-#endif
 #ifdef CONFIG_KBDFRONT
        case FTYPE_KBD:
             shutdown_kbdfront(files[fd].dev);
@@ -640,7 +619,6 @@ static const char *file_types[] = {
     [FTYPE_NONE]    = "none",
     [FTYPE_CONSOLE] = "console",
     [FTYPE_SOCKET]  = "socket",
-    [FTYPE_TAP]     = "net",
     [FTYPE_KBD]     = "kbd",
     [FTYPE_FB]      = "fb",
 };
@@ -817,7 +795,6 @@ static int select_poll(int nfds, fd_set *readfds, fd_set 
*writefds, fd_set *exce
                 n++;
            FD_CLR(i, exceptfds);
            break;
-       case FTYPE_TAP:
        case FTYPE_KBD:
        case FTYPE_FB:
            if (FD_ISSET(i, readfds)) {
diff --git a/netfront.c b/netfront.c
index 7696451..f86c6a2 100644
--- a/netfront.c
+++ b/netfront.c
@@ -248,14 +248,14 @@ void netfront_select_handler(evtchn_port_t port, struct 
pt_regs *regs, void *dat
 {
     int flags;
     struct netfront_dev *dev = data;
-    int fd = dev->fd;
+    struct file *file = get_file_from_fd(dev->fd);
 
     local_irq_save(flags);
     network_tx_buf_gc(dev);
     local_irq_restore(flags);
 
-    if (fd != -1)
-        files[fd].read = true;
+    if ( file )
+        file->read = true;
     wake_up(&netfront_queue);
 }
 #endif
@@ -565,8 +565,54 @@ error:
 }
 
 #ifdef HAVE_LIBC
+static int netfront_read(int fd, void *buf, size_t nbytes)
+{
+    ssize_t ret;
+    struct file *file = get_file_from_fd(fd);
+
+    ret = netfront_receive(file->dev, buf, nbytes);
+    if ( ret <= 0 )
+    {
+        errno = EAGAIN;
+        return -1;
+    }
+
+    return ret;
+}
+
+static int netfront_write(int fd, const void *buf, size_t nbytes)
+{
+    struct file *file = get_file_from_fd(fd);
+
+    netfront_xmit(file->dev, (void *)buf, nbytes);
+
+    return nbytes;
+}
+
+static int netfront_close_fd(int fd)
+{
+    struct file *file = get_file_from_fd(fd);
+
+    shutdown_netfront(file->dev);
+
+    return 0;
+}
+
+static struct file_ops netfront_ops = {
+    .name = "net",
+    .read = netfront_read,
+    .write = netfront_write,
+    .close = netfront_close_fd,
+    .select_rd = select_read_flag,
+};
+
 int netfront_tap_open(char *nodename) {
     struct netfront_dev *dev;
+    struct file *file;
+    static unsigned int ftype_netfront;
+
+    if ( !ftype_netfront )
+        ftype_netfront = alloc_file_type(&netfront_ops);
 
     dev = init_netfront(nodename, NETIF_SELECT_RX, NULL, NULL);
     if (!dev) {
@@ -574,9 +620,10 @@ int netfront_tap_open(char *nodename) {
        errno = EIO;
        return -1;
     }
-    dev->fd = alloc_fd(FTYPE_TAP);
+    dev->fd = alloc_fd(ftype_netfront);
     printk("tap_open(%s) -> %d\n", nodename, dev->fd);
-    files[dev->fd].dev = dev;
+    file = get_file_from_fd(dev->fd);
+    file->dev = dev;
     return dev->fd;
 }
 #endif
@@ -772,7 +819,8 @@ void netfront_xmit(struct netfront_dev *dev, unsigned char* 
data,int len)
 ssize_t netfront_receive(struct netfront_dev *dev, unsigned char *data, size_t 
len)
 {
     unsigned long flags;
-    int fd = dev->fd;
+    struct file *file = get_file_from_fd(dev->fd);
+
     ASSERT(current == main_thread);
 
     dev->rlen = 0;
@@ -781,9 +829,9 @@ ssize_t netfront_receive(struct netfront_dev *dev, unsigned 
char *data, size_t l
 
     local_irq_save(flags);
     network_rx(dev);
-    if (!dev->rlen && fd != -1)
+    if ( !dev->rlen && file )
         /* No data for us, make select stop returning */
-        files[fd].read = false;
+        file->read = false;
     /* Before re-enabling the interrupts, in case a packet just arrived in the
      * meanwhile. */
     local_irq_restore(flags);
-- 
2.26.2