From: Adrien Mazarguil <adrien.mazarg...@6wind.com>
This parameter enables applications to provide device definitions through
an arbitrary file descriptor number.
Signed-off-by: Adrien Mazarguil <adrien.mazarg...@6wind.com>
Cc: Gaetan Rivet <gaetan.ri...@6wind.com>
---
doc/guides/nics/fail_safe.rst | 9 ++++
drivers/net/failsafe/failsafe_args.c | 86 ++++++++++++++++++++++++++++++++-
drivers/net/failsafe/failsafe_private.h | 3 ++
3 files changed, 97 insertions(+), 1 deletion(-)
diff --git a/doc/guides/nics/fail_safe.rst b/doc/guides/nics/fail_safe.rst
index c4e3d2e..5b1b47e 100644
--- a/doc/guides/nics/fail_safe.rst
+++ b/doc/guides/nics/fail_safe.rst
@@ -106,6 +106,15 @@ Fail-safe command line parameters
All commas within the ``shell command`` are replaced by spaces before
executing the command. This helps using scripts to specify devices.
+- **fd(<file descriptor number>)** parameter
+
+ This parameter reads a device definition from an arbitrary file descriptor
+ number in ``<iface>`` format as described above.
+
+ The file descriptor is read in non-blocking mode and is never closed in
+ order to take only the last line into account (unlike ``exec()``) at every
+ probe attempt.
+
- **mac** parameter [MAC address]
This parameter allows the user to set a default MAC address to the fail-safe
diff --git a/drivers/net/failsafe/failsafe_args.c
b/drivers/net/failsafe/failsafe_args.c
index ec63ac9..7a86051 100644
--- a/drivers/net/failsafe/failsafe_args.c
+++ b/drivers/net/failsafe/failsafe_args.c
@@ -31,7 +31,11 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
+#include <unistd.h>
#include <errno.h>
#include <rte_debug.h>
@@ -161,6 +165,73 @@ typedef int (parse_cb)(struct rte_eth_dev *dev, const char
*params,
}
static int
+fs_read_fd(struct sub_device *sdev, char *fd_str)
+{
+ FILE *fp = NULL;
+ int fd = -1;
+ /* store possible newline as well */
+ char output[DEVARGS_MAXLEN + 1];
+ int err = -ENODEV;
+ int ret;
+
+ RTE_ASSERT(fd_str != NULL || sdev->fd_str != NULL);
+ if (sdev->fd_str == NULL) {
+ sdev->fd_str = strdup(fd_str);
+ if (sdev->fd_str == NULL) {
+ ERROR("Command line allocation failed");
+ return -ENOMEM;
+ }
+ }
+ errno = 0;
+ fd = strtol(fd_str, &fd_str, 0);
+ if (errno || *fd_str || fd < 0) {
+ ERROR("Parsing FD number failed");
+ goto error;
+ }
+ /* Fiddle with copy of file descriptor */
+ fd = dup(fd);
+ if (fd == -1)
+ goto error;
+ ret = fcntl(fd, F_GETFL);
+ if (ret == -1)
+ goto error;
+ ret = fcntl(fd, F_SETFL, fd | O_NONBLOCK);
+ if (ret == -1)
+ goto error;
+ fp = fdopen(fd, "r");
+ if (!fp)
+ goto error;
+ fd = -1;
+ /* Only take the last line into account */
+ ret = 0;
+ while (fgets(output, sizeof(output), fp))
+ ++ret;
+ if (feof(fp)) {
+ if (!ret)
+ goto error;
+ } else if (ferror(fp)) {
+ if (errno != EAGAIN || !ret)
+ goto error;
+ } else if (!ret) {
+ goto error;
+ }
+ /* Line must end with a newline character */
+ fs_sanitize_cmdline(output);
+ if (output[0] == '\0')
+ goto error;
+ ret = fs_parse_device(sdev, output);
+ if (ret)
+ ERROR("Parsing device '%s' failed", output);
+ err = ret;
+error:
+ if (fp)
+ fclose(fp);
+ if (fd != -1)
+ close(fd);
+ return err;
+}
+
+static int
fs_parse_device_param(struct rte_eth_dev *dev, const char *param,
uint8_t head)
{
@@ -202,6 +273,14 @@ typedef int (parse_cb)(struct rte_eth_dev *dev, const char
*params,
}
if (ret)
goto free_args;
+ } else if (strncmp(param, "fd", 2) == 0) {
+ ret = fs_read_fd(sdev, args);
+ if (ret == -ENODEV) {
+ DEBUG("Reading device info from FD failed");
+ ret = 0;
+ }
+ if (ret)
+ goto free_args;
} else {
ERROR("Unrecognized device type: %.*s", (int)b, param);
return -EINVAL;
@@ -409,6 +488,8 @@ typedef int (parse_cb)(struct rte_eth_dev *dev, const char
*params,
FOREACH_SUBDEV(sdev, i, dev) {
free(sdev->cmdline);
sdev->cmdline = NULL;
+ free(sdev->fd_str);
+ sdev->fd_str = NULL;
free(sdev->devargs.args);
sdev->devargs.args = NULL;
}
@@ -424,7 +505,8 @@ typedef int (parse_cb)(struct rte_eth_dev *dev, const char
*params,
param[b] != '\0')
b++;
if (strncmp(param, "dev", b) != 0 &&
- strncmp(param, "exec", b) != 0) {
+ strncmp(param, "exec", b) != 0 &&
+ strncmp(param, "fd", b) != 0) {
ERROR("Unrecognized device type: %.*s", (int)b, param);
return -EINVAL;
}
@@ -463,6 +545,8 @@ typedef int (parse_cb)(struct rte_eth_dev *dev, const char
*params,
continue;
if (sdev->cmdline)
ret = fs_execute_cmd(sdev, sdev->cmdline);
+ else if (sdev->fd_str)
+ ret = fs_read_fd(sdev, sdev->fd_str);
else
ret = fs_parse_sub_device(sdev);
if (ret == 0)
diff --git a/drivers/net/failsafe/failsafe_private.h
b/drivers/net/failsafe/failsafe_private.h
index d81cc3c..a0d3675 100644
--- a/drivers/net/failsafe/failsafe_private.h
+++ b/drivers/net/failsafe/failsafe_private.h
@@ -48,6 +48,7 @@
#define PMD_FAILSAFE_PARAM_STRING \
"dev(<ifc>)," \
"exec(<shell command>)," \
+ "fd(<fd number>)," \
"mac=mac_addr," \
"hotplug_poll=u64" \
""
@@ -111,6 +112,8 @@ struct sub_device {
struct fs_stats stats_snapshot;
/* Some device are defined as a command line */
char *cmdline;
+ /* Others are retrieved through a file descriptor */
+ char *fd_str;
/* fail-safe device backreference */
struct rte_eth_dev *fs_dev;
/* flag calling for recollection */
--
1.8.3.1
