LDPRELOAD: readv writev v2

Move the vector iteration down to vcom_socket

Change-Id: I5bb8d0d34a18ea15daf7a385443e046cb64313a1
Signed-off-by: Steven <sluong@cisco.com>

4 files changed, 173 insertions, 60 deletions

diff --git a/vcl-ldpreload/src/libvcl-ldpreload/vcom.c b/vcl-ldpreload/src/libvcl-ldpreload/vcom.c
index 75054eb..4da2d99 100644
--- a/vcl-ldpreload/src/libvcl-ldpreload/vcom.c
+++ b/vcl-ldpreload/src/libvcl-ldpreload/vcom.c
@@ -18,10 +18,6 @@
 #include <dlfcn.h>
 #include <pthread.h>
 #include <time.h>
-#include <sys/uio.h>
-#include <limits.h>
-#define __need_IOV_MAX
-#include <bits/stdio_lim.h>
 #include <stdarg.h>
 
 #include <libvcl-ldpreload/vcom_socket_wrapper.h>
@@ -264,41 +260,30 @@ read (int __fd, void *__buf, size_t __nbytes)
 }
 
 ssize_t
+vcom_readv (int __fd, const struct iovec * __iov, int __iovcnt)
+{
+  if (vcom_init () != 0)
+    {
+      return -1;
+    }
+
+  return vcom_socket_readv (__fd, __iov, __iovcnt);
+}
+
+ssize_t
 readv (int __fd, const struct iovec * __iov, int __iovcnt)
 {
-  size_t len = 0;
-  ssize_t total = 0;
+  ssize_t size = 0;
 
   if (is_vcom_socket_fd (__fd))
     {
-      if (__iov == 0 || __iovcnt == 0 || __iovcnt > IOV_MAX)
-	return -EINVAL;
-
-      /* Sanity check */
-      for (int i = 0; i < __iovcnt; ++i)
-	{
-	  if (SSIZE_MAX - len < __iov[i].iov_len)
-	    return -EINVAL;
-	  len += __iov[i].iov_len;
-	}
-
-      for (int i = 0; i < __iovcnt; ++i)
+      size = vcom_readv (__fd, __iov, __iovcnt);
+      if (size < 0)
 	{
-	  len = vcom_read (__fd, __iov[i].iov_base, __iov[i].iov_len);
-	  if (len < 0)
-	    {
-	      if (total > 0)
-		return total;
-	      else
-		{
-		  errno = len;;
-		  return -1;
-		}
-	    }
-	  else
-	    total += len;
+	  errno = -size;
+	  return -1;
 	}
-      return (total);
+      return size;
     }
   else
     return libc_readv (__fd, __iov, __iovcnt);
@@ -352,41 +337,30 @@ write (int __fd, const void *__buf, size_t __n)
 }
 
 ssize_t
+vcom_writev (int __fd, const struct iovec * __iov, int __iovcnt)
+{
+  if (vcom_init () != 0)
+    {
+      return -1;
+    }
+
+  return vcom_socket_writev (__fd, __iov, __iovcnt);
+}
+
+ssize_t
 writev (int __fd, const struct iovec * __iov, int __iovcnt)
 {
-  size_t len = 0;
-  ssize_t total = 0;
+  ssize_t size = 0;
 
   if (is_vcom_socket_fd (__fd))
     {
-      if (__iov == 0 || __iovcnt == 0 || __iovcnt > IOV_MAX)
-	return -EINVAL;
-
-      /* Sanity check */
-      for (int i = 0; i < __iovcnt; ++i)
-	{
-	  if (SSIZE_MAX - len < __iov[i].iov_len)
-	    return -EINVAL;
-	  len += __iov[i].iov_len;
-	}
-
-      for (int i = 0; i < __iovcnt; ++i)
+      size = vcom_writev (__fd, __iov, __iovcnt);
+      if (size < 0)
 	{
-	  len = vcom_write (__fd, __iov[i].iov_base, __iov[i].iov_len);
-	  if (len < 0)
-	    {
-	      if (total > 0)
-		return total;
-	      else
-		{
-		  errno = len;;
-		  return -1;
-		}
-	    }
-	  else
-	    total += len;
+	  errno = -size;
+	  return -1;
 	}
-      return (total);
+      return size;
     }
   else
     return libc_writev (__fd, __iov, __iovcnt);
diff --git a/vcl-ldpreload/src/libvcl-ldpreload/vcom.h b/vcl-ldpreload/src/libvcl-ldpreload/vcom.h
index d751fe1..1706c0e 100644
--- a/vcl-ldpreload/src/libvcl-ldpreload/vcom.h
+++ b/vcl-ldpreload/src/libvcl-ldpreload/vcom.h
@@ -44,6 +44,10 @@ extern ssize_t __wur vcom_read (int __fd, void *__buf, size_t __nbytes);
 
 extern ssize_t __wur vcom_write (int __fd, const void *__buf, size_t __n);
 
+extern ssize_t __wur vcom_readv (int __fd, const struct iovec * __iov, int __iovcnt);
+
+extern ssize_t __wur vcom_writev (int __fd, const struct iovec * __iov, int __iovcnt);
+
 /*
  * vpp implementation of glibc APIs from <fcntl.h>
  */
diff --git a/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.c b/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.c
index ba8a489..0fd2bb1 100644
--- a/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.c
+++ b/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.c
@@ -14,6 +14,10 @@
  */
 #include <unistd.h>
 #include <stdio.h>
+#include <sys/uio.h>
+#include <limits.h>
+#define __need_IOV_MAX
+#include <bits/stdio_lim.h>
 
 #include <vppinfra/types.h>
 #include <vppinfra/hash.h>
@@ -542,6 +546,93 @@ vcom_socket_read (int __fd, void *__buf, size_t __nbytes)
 }
 
 ssize_t
+vcom_socket_readv (int __fd, const struct iovec * __iov, int __iovcnt)
+{
+  int rv;
+  vcom_socket_main_t *vsm = &vcom_socket_main;
+  uword *p;
+  vcom_socket_t *vsock;
+  ssize_t total = 0, len = 0;
+
+  p = hash_get (vsm->sockidx_by_fd, __fd);
+  if (!p)
+    return -EBADF;
+
+  vsock = pool_elt_at_index (vsm->vsockets, p[0]);
+  if (!vsock)
+    return -ENOTSOCK;
+
+  if (vsock->type != SOCKET_TYPE_VPPCOM_BOUND)
+    return -EINVAL;
+
+  if (__iov == 0 || __iovcnt == 0 || __iovcnt > IOV_MAX)
+    return -EINVAL;
+
+  /* Sanity check */
+  for (int i = 0; i < __iovcnt; ++i)
+    {
+      if (SSIZE_MAX - len < __iov[i].iov_len)
+	return -EINVAL;
+      len += __iov[i].iov_len;
+    }
+
+  rv = vcom_fcntl (__fd, F_GETFL, 0);
+  if (rv < 0)
+    {
+      return rv;
+    }
+
+  /* is blocking */
+  if (!(rv & O_NONBLOCK))
+    {
+      do
+	{
+	  for (int i = 0; i < __iovcnt; ++i)
+	    {
+	      rv = vppcom_session_read (vsock->sid, __iov[i].iov_base,
+					__iov[i].iov_len);
+	      if (rv < 0)
+		break;
+	      else
+		{
+		  total += rv;
+		  if (rv < __iov[i].iov_len)
+	            /* Read less than buffer provided, no point to continue */
+		    break;
+		}
+	    }
+	}
+      while ((rv == -EAGAIN || rv == -EWOULDBLOCK) && total == 0);
+      return total;
+    }
+
+  /* is non blocking */
+  for (int i = 0; i < __iovcnt; ++i)
+    {
+      rv = vppcom_session_read (vsock->sid, __iov[i].iov_base,
+				__iov[i].iov_len);
+      if (rv < 0)
+	{
+	  if (total > 0)
+	    break;
+	  else
+	    {
+	      errno = rv;
+	      return rv;
+	    }
+	}
+      else
+	{
+	  total += rv;
+	  if (rv < __iov[i].iov_len)
+	    /* Read less than buffer provided, no point to continue */
+	    break;
+	}
+    }
+  return total;
+}
+
+ssize_t
 vcom_socket_write (int __fd, const void *__buf, size_t __n)
 {
   int rv = -1;
@@ -569,6 +660,46 @@ vcom_socket_write (int __fd, const void *__buf, size_t __n)
   return rv;
 }
 
+ssize_t
+vcom_socket_writev (int __fd, const struct iovec * __iov, int __iovcnt)
+{
+  int rv = -1;
+  ssize_t total = 0;
+  vcom_socket_main_t *vsm = &vcom_socket_main;
+  uword *p;
+  vcom_socket_t *vsock;
+
+  p = hash_get (vsm->sockidx_by_fd, __fd);
+  if (!p)
+    return -EBADF;
+
+  vsock = pool_elt_at_index (vsm->vsockets, p[0]);
+  if (!vsock)
+    return -ENOTSOCK;
+
+  if (vsock->type != SOCKET_TYPE_VPPCOM_BOUND)
+    return -EINVAL;
+
+  if (__iov == 0 || __iovcnt == 0 || __iovcnt > IOV_MAX)
+    return -EINVAL;
+
+  for (int i = 0; i < __iovcnt; ++i)
+    {
+      rv = vppcom_session_write (vsock->sid, __iov[i].iov_base,
+				 __iov[i].iov_len);
+      if (rv < 0)
+	{
+	  if (total > 0)
+	    break;
+	  else
+	    return rv;
+	}
+      else
+	total += rv;
+    }
+  return total;
+}
+
 /*
  * RETURN:  0 - invalid cmd
  *          1 - cmd not handled by vcom and vppcom
diff --git a/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.h b/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.h
index 903f740..e966895 100644
--- a/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.h
+++ b/vcl-ldpreload/src/libvcl-ldpreload/vcom_socket.h
@@ -314,8 +314,12 @@ int vcom_socket_close (int __fd);
 
 ssize_t vcom_socket_read (int __fd, void *__buf, size_t __nbytes);
 
+ssize_t vcom_socket_readv (int __fd, const struct iovec * __iov, int __iovcnt);
+
 ssize_t vcom_socket_write (int __fd, const void *__buf, size_t __n);
 
+ssize_t vcom_socket_writev (int __fd, const struct iovec * __iov, int __iovcnt);
+
 int vcom_socket_fcntl_va (int __fd, int __cmd, va_list __ap);
 
 int