For the prototype of netdev_features_t is u64, and the number of netdevice feature bits is 64 now. So there is no space to introduce new feature bit.
This patchset try to solve it by change the prototype of netdev_features_t from u64 to structure below: typedef struct { DECLARE_BITMAP(bits, NETDEV_FEATURE_COUNT); } netdev_features_t;
With this change, it's necessary to introduce a set of bitmap operation helpers for netdev features. As the nic drivers are not supposed to modify netdev_features directly, it also introduces wrappers helpers to this. [patch 20]
There are a set of helpes named as "netdev_features_xxx", and I want to add similar helpers for netdev features members, named as netdev_XXX_features_xxx.(xxx: and/or/xor.., XXX: hw/vlan/mpls...) To make the helpers name differentiable, rename netdev->features to netdev->active_features. [patch 2] For example: #define netdev_active_features_set_bit(ndev, nr) \ netdev_features_set_bit(nr, &ndev->active_features)
To avoid mistake using NETIF_F_XXX as NETIF_F_XXX_BIT as input macroes for above helpers, remove all the macroes of NETIF_F_XXX. [patch 20]
The features group macroes in netdev_features.h are replaced by a set of const features defined in netdev_features.c. [patch 3-4] For example: macro NETIF_F_ALL_TSO is replaced by netdev_all_tso_features
There are some drivers(e.g. sfc) use netdev_features in global structure initialization. Changed the its netdev_features_t memeber to netdev_features_t *, and make it prefer to a netdev_features_t global variables. [patch 5]
As suggestion from Andrew Lunn, I wrote some semantic patches to do the work(replacing the netdev features operator by helpers). [patch 8-19] To make the semantic patches simple, I split the complex opreation of netdev_features to simple logical operation. [patch 6, 7]
With the prototype is no longer u64, the implementation of print interface for netdev features(%pNF) is changed to bitmap. [patch 20]
The whole work is not complete yet. I just use these changes on several files(hns3 driver, sfc drivers, net/ethtool, net/core/dev.c), in order to show how these helpers will be used. I want to get more suggestions for this scheme, any comments would be appreciated.
The former discussion please see [1][2][3].
[1]:https://www.spinics.net/lists/netdev/msg769952.html [2]:https://www.spinics.net/lists/netdev/msg777764.html [3]:https://lore.kernel.org/netdev/20211107101519.29264-1-shenjian15@huawei.com/...
ChangeLog: V4->V5: adjust the patch structure, use semantic patch with coccinelle V3->V4: rename netdev->features to netdev->active_features remove helpes for handle first 64 bits remove __NETIF_F(name) macroes replace features group macroes with const features V2->V3: use structure for bitmap, suggest by Edward Cree V1->V2: Extend the prototype from u64 to bitmap, suggest by Andrew Lunn
Jian Shen (20): net: rename net_device->features to net_device->active_features net: introduce operation helpers for netdev features net: replace general features macroes with global netdev_features variables net: replace multiple feature bits with netdev features array net: sfc: replace const features initialization with netdev features array net: simplify the netdev features expression net: adjust variables definition for netdev_features_t net: use netdev_features_set_bit helpers net: use netdev_features_or helpers net: use netdev_features_xor helpers net: use netdev_features_clear_bit helpers net: use netdev_features_andnot helpers net: use netdev_features_test_bit helpers net: use netdev_features_intersects helpers net: use netdev_features_and helpers net: use netdev_features_subset helpers net: use netdev_features_equal helpers net: use netdev_set_xxx_features helpers net: use netdev_xxx_features helpers net: redefine the prototype of netdev_features_t
.../net/ethernet/hisilicon/hns3/hns3_enet.c | 116 ++- .../ethernet/hisilicon/hns3/hns3_ethtool.c | 4 +- drivers/net/ethernet/sfc/ef10.c | 43 +- drivers/net/ethernet/sfc/ef100_nic.c | 57 +- drivers/net/ethernet/sfc/ef100_rx.c | 4 +- drivers/net/ethernet/sfc/ef100_tx.c | 8 +- drivers/net/ethernet/sfc/ef10_sriov.c | 6 +- drivers/net/ethernet/sfc/efx.c | 96 ++- drivers/net/ethernet/sfc/efx_common.c | 32 +- drivers/net/ethernet/sfc/falcon/efx.c | 75 +- drivers/net/ethernet/sfc/falcon/efx.h | 3 + drivers/net/ethernet/sfc/falcon/falcon.c | 4 +- drivers/net/ethernet/sfc/falcon/net_driver.h | 4 +- drivers/net/ethernet/sfc/falcon/rx.c | 4 +- drivers/net/ethernet/sfc/farch.c | 2 +- drivers/net/ethernet/sfc/mcdi_filters.c | 13 +- drivers/net/ethernet/sfc/mcdi_port_common.c | 2 +- drivers/net/ethernet/sfc/net_driver.h | 4 +- drivers/net/ethernet/sfc/rx.c | 2 +- drivers/net/ethernet/sfc/rx_common.c | 5 +- drivers/net/ethernet/sfc/rx_common.h | 4 + drivers/net/ethernet/sfc/siena.c | 3 +- include/linux/netdev_features.h | 189 ++--- include/linux/netdevice.h | 722 +++++++++++++++++- lib/vsprintf.c | 11 +- net/core/dev.c | 419 ++++++---- net/core/netdev_features.c | 276 +++++++ net/ethtool/features.c | 77 +- net/ethtool/ioctl.c | 140 ++-- 29 files changed, 1797 insertions(+), 528 deletions(-) create mode 100644 net/core/netdev_features.c