vlib: vfio code rework

Change-Id: I99cf3e7cc991aa7d32385a155c707a6516516117
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 282 insertions, 0 deletions

diff --git a/src/vlib/linux/vfio.c b/src/vlib/linux/vfio.c
new file mode 100644
index 00000000000..dffe49ce7b2
--- /dev/null
+++ b/src/vlib/linux/vfio.c
@@ -0,0 +1,282 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * pci.c: Linux user space PCI bus management.
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <linux/vfio.h>
+#include <sys/ioctl.h>
+
+#include <vppinfra/linux/sysfs.h>
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vlib/pci/pci.h>
+#include <vlib/linux/vfio.h>
+#include <vlib/physmem.h>
+
+linux_vfio_main_t vfio_main;
+
+static int
+map_regions (vlib_main_t * vm, int fd)
+{
+  vlib_physmem_main_t *vpm = &vm->physmem_main;
+  vlib_physmem_region_t *pr;
+  struct vfio_iommu_type1_dma_map dm = { 0 };
+  int i;
+
+  dm.argsz = sizeof (struct vfio_iommu_type1_dma_map);
+  dm.flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE;
+
+  /* *INDENT-OFF* */
+  pool_foreach (pr, vpm->regions,
+    {
+      vec_foreach_index (i, pr->page_table)
+        {
+	  int rv;
+	  dm.vaddr = pointer_to_uword (pr->mem) + (i << pr->log2_page_size);
+	  dm.size = 1 << pr->log2_page_size;
+	  dm.iova = pr->page_table[i];
+	  if ((rv = ioctl (fd, VFIO_IOMMU_MAP_DMA, &dm)))
+	    return rv;
+        }
+    });
+  /* *INDENT-ON* */
+  return 0;
+}
+
+static clib_error_t *
+scan_vfio_fd (void *arg, u8 * path_name, u8 * file_name)
+{
+  linux_vfio_main_t *lvm = &vfio_main;
+  const char fn[] = "/dev/vfio/vfio";
+  char buff[sizeof (fn)] = { 0 };
+  int fd;
+  u8 *path = format (0, "%v%c", path_name, 0);
+
+  if (readlink ((char *) path, buff, sizeof (fn)) + 1 != sizeof (fn))
+    goto done;
+
+  if (strncmp (fn, buff, sizeof (fn)))
+    goto done;
+
+  fd = atoi ((char *) file_name);
+  if (fd != lvm->container_fd)
+    lvm->ext_container_fd = atoi ((char *) file_name);
+
+done:
+  vec_free (path);
+  return 0;
+}
+
+void
+linux_vfio_dma_map_regions (vlib_main_t * vm)
+{
+  linux_vfio_main_t *lvm = &vfio_main;
+
+  if (lvm->container_fd != -1)
+    map_regions (vm, lvm->container_fd);
+
+  if (lvm->ext_container_fd == -1)
+    foreach_directory_file ("/proc/self/fd", scan_vfio_fd, 0, 0);
+
+  if (lvm->ext_container_fd != -1)
+    map_regions (vm, lvm->ext_container_fd);
+}
+
+static linux_pci_vfio_iommu_group_t *
+get_vfio_iommu_group (int group)
+{
+  linux_vfio_main_t *lvm = &vfio_main;
+  uword *p;
+
+  p = hash_get (lvm->iommu_pool_index_by_group, group);
+
+  return p ? pool_elt_at_index (lvm->iommu_groups, p[0]) : 0;
+}
+
+static clib_error_t *
+open_vfio_iommu_group (int group)
+{
+  linux_vfio_main_t *lvm = &vfio_main;
+  linux_pci_vfio_iommu_group_t *g;
+  clib_error_t *err = 0;
+  struct vfio_group_status group_status;
+  u8 *s = 0;
+  int fd;
+
+  g = get_vfio_iommu_group (group);
+  if (g)
+    {
+      g->refcnt++;
+      return 0;
+    }
+  s = format (s, "/dev/vfio/%u%c", group, 0);
+  fd = open ((char *) s, O_RDWR);
+  if (fd < 0)
+    return clib_error_return_unix (0, "open '%s'", s);
+
+  group_status.argsz = sizeof (group_status);
+  if (ioctl (fd, VFIO_GROUP_GET_STATUS, &group_status) < 0)
+    {
+      err = clib_error_return_unix (0, "ioctl(VFIO_GROUP_GET_STATUS) '%s'",
+				    s);
+      goto error;
+    }
+
+  if (!(group_status.flags & VFIO_GROUP_FLAGS_VIABLE))
+    {
+      err = clib_error_return (0, "iommu group %d is not viable (not all "
+			       "devices in this group bound to vfio-pci)",
+			       group);
+      goto error;
+    }
+
+  if (ioctl (fd, VFIO_GROUP_SET_CONTAINER, &lvm->container_fd) < 0)
+    {
+      err = clib_error_return_unix (0, "ioctl(VFIO_GROUP_SET_CONTAINER) '%s'",
+				    s);
+      goto error;
+    }
+
+  if (lvm->iommu_mode == 0)
+    {
+      if (ioctl (lvm->container_fd, VFIO_SET_IOMMU, VFIO_TYPE1_IOMMU) < 0)
+	{
+	  err = clib_error_return_unix (0, "ioctl(VFIO_SET_IOMMU) "
+					"'/dev/vfio/vfio'");
+	  goto error;
+	}
+      lvm->iommu_mode = VFIO_TYPE1_IOMMU;
+    }
+
+
+  pool_get (lvm->iommu_groups, g);
+  g->fd = fd;
+  g->refcnt = 1;
+  hash_set (lvm->iommu_pool_index_by_group, group, g - lvm->iommu_groups);
+  vec_free (s);
+  return 0;
+error:
+  close (fd);
+  return err;
+}
+
+clib_error_t *
+linux_vfio_group_get_device_fd (vlib_pci_addr_t * addr, int *fdp)
+{
+  clib_error_t *err = 0;
+  linux_pci_vfio_iommu_group_t *g;
+  u8 *s = 0;
+  int iommu_group;
+  u8 *tmpstr;
+  int fd;
+
+  s = format (s, "/sys/bus/pci/devices/%U/iommu_group", format_vlib_pci_addr,
+	      addr);
+  tmpstr = clib_sysfs_link_to_name ((char *) s);
+  if (tmpstr)
+    {
+      iommu_group = atoi ((char *) tmpstr);
+      vec_free (tmpstr);
+    }
+  else
+    {
+      err = clib_error_return (0, "Cannot find IOMMU group for PCI device ",
+			       "'%U'", format_vlib_pci_addr, addr);
+      goto error;
+    }
+  vec_reset_length (s);
+
+  if ((err = open_vfio_iommu_group (iommu_group)))
+    return err;
+
+  g = get_vfio_iommu_group (iommu_group);
+
+  s = format (s, "%U%c", format_vlib_pci_addr, addr, 0);
+  if ((fd = ioctl (g->fd, VFIO_GROUP_GET_DEVICE_FD, (char *) s)) < 0)
+    {
+      err = clib_error_return_unix (0, "ioctl(VFIO_GROUP_GET_DEVICE_FD) '%U'",
+				    format_vlib_pci_addr, addr);
+      goto error;
+    }
+  vec_reset_length (s);
+
+  *fdp = fd;
+
+error:
+  vec_free (s);
+  return err;
+}
+
+clib_error_t *
+linux_vfio_init (vlib_main_t * vm)
+{
+  linux_vfio_main_t *lvm = &vfio_main;
+  int fd;
+
+  lvm->ext_container_fd = -1;
+
+  fd = open ("/dev/vfio/vfio", O_RDWR);
+
+  /* check if iommu is available */
+  if (fd != -1)
+    {
+      if (ioctl (fd, VFIO_GET_API_VERSION) != VFIO_API_VERSION)
+	{
+	  close (fd);
+	  fd = -1;
+	}
+      else if (ioctl (fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) == 1)
+	lvm->flags |= LINUX_VFIO_F_HAVE_IOMMU;
+    }
+
+  lvm->iommu_pool_index_by_group = hash_create (0, sizeof (uword));
+  lvm->container_fd = fd;
+  return 0;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */