Re: [PATCH v5 2/7] bus: introduce parsing functionality

On Tue, Jun 27, 2017 at 09:26:20PM +0200, Jan Blunck wrote:

On Wed, Jun 21, 2017 at 1:30 AM, Gaetan Rivet [off-list ref] wrote:

quoted

This operation can be used either to validate that a device
representation can be understood by a bus, as well as store the resulting
specialized device representation in any format determined by the bus.

Again, I don't think this makes sense to have. Also there is no user
for this as far as I can see. The bus specific device representation
should come from the scan function instead of this.

I think it makes sense that scanning would store this representation
yes. The issue is that it requires another rte_bus_scan API evolution,
which is beyond this patchset.

Keep in mind that I was bound when writing this to follow the existing
API. I agree that some cleanup could come up in the EAL, but it cannot
all happen at once. These first steps (generic devargs / vdev & PCI move
to drivers/bus) serve to trim the EAL before these changes.

quoted

Signed-off-by: Gaetan Rivet <redacted>
---
 lib/librte_eal/common/include/rte_bus.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/lib/librte_eal/common/include/rte_bus.h b/lib/librte_eal/common/include/rte_bus.h
index b220299..05503ea 100644
--- a/lib/librte_eal/common/include/rte_bus.h
+++ b/lib/librte_eal/common/include/rte_bus.h

@@ -117,6 +117,26 @@ typedef struct rte_device * (*rte_bus_plug_t)(struct rte_devargs *da);
 typedef int (*rte_bus_unplug_t)(struct rte_device *dev);

 /**
+ * Bus specific parsing function.
+ * Validates the syntax used in the textual representation of a device,
+ * If the syntax is valid and ``addr`` is not NULL, writes the bus-specific
+ * device representation to ``addr``.
+ *
+ * @param[in] name
+ *     device textual description
+ *
+ * @param[out] addr
+ *     device information location address, into which parsed info
+ *     should be written. If NULL, nothing should be written, which
+ *     is not an error.
+ *
+ * @return
+ *     0 if parsing was successful.
+ *     !0 for any error.
+ */
+typedef int (*rte_bus_parse_t)(const char *name, void *addr);
+
+/**
  * A structure describing a generic bus.
  */
 struct rte_bus {

@@ -127,6 +147,7 @@ struct rte_bus {
        rte_bus_find_device_t find_device; /**< Find device on bus */
        rte_bus_plug_t plug;         /**< Probe single device for drivers */
        rte_bus_unplug_t unplug;     /**< Remove single device from driver */
+       rte_bus_parse_t parse;       /**< Parse a device name */
 };

 /**
--

2.1.4

-- 
Gaëtan Rivet
6WIND