bus/fslmc: fix VFIO group descriptor check

The issue is that a file descriptor at 0 is a valid one. Currently
the file not found, the return value will be set to 0. As a result,
it is impossible to distinguish between a correct descriptor and a
failed return value. Fix it to return -ENOENT instead of 0.

Fixes: a69f79300262 ("bus/fslmc: support multi VFIO group")
Cc: stable@dpdk.org
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>

diff --git a/drivers/bus/fslmc/fslmc_vfio.c b/drivers/bus/fslmc/fslmc_vfio.c
index 9134ec5..2e1803a 100644 (file)
--- a/drivers/bus/fslmc/fslmc_vfio.c
+++ b/drivers/bus/fslmc/fslmc_vfio.c
@@ -457,11 +457,14 @@ fslmc_vfio_setup_device(const char *sysfs_base, const char *dev_addr,
 
        /* get the actual group fd */
        vfio_group_fd = rte_vfio_get_group_fd(iommu_group_no);
-       if (vfio_group_fd < 0)
+       if (vfio_group_fd < 0 && vfio_group_fd != -ENOENT)
                return -1;
 
-       /* if group_fd == 0, that means the device isn't managed by VFIO */
-       if (vfio_group_fd == 0) {
+       /*
+        * if vfio_group_fd == -ENOENT, that means the device
+        * isn't managed by VFIO
+        */
+       if (vfio_group_fd == -ENOENT) {
                RTE_LOG(WARNING, EAL, " %s not managed by VFIO driver, skipping\n",
                                dev_addr);
                return 1;