On Mon, Mar 15, 2021 at 07:12:39PM +0200, Moshe Shemesh wrote:
> From: Vladyslav Tarasiuk <vladysl...@nvidia.com>
>
> Define get_module_eeprom_data_by_page() ethtool callback and implement
> netlink infrastructure.
>
> get_module_eeprom_data_by_page() allows network drivers to dump a part
> of module's EEPROM specified by page and bank numbers along with offset
> and length. It is effectively a netlink replacement for
> get_module_info() and get_module_eeprom() pair, which is needed due to
> emergence of complex non-linear EEPROM layouts.
>
> Signed-off-by: Vladyslav Tarasiuk <vladysl...@nvidia.com>
> ---
> Documentation/networking/ethtool-netlink.rst | 34 ++++-
> include/linux/ethtool.h | 8 +-
> include/uapi/linux/ethtool.h | 25 +++
> include/uapi/linux/ethtool_netlink.h | 19 +++
> net/ethtool/Makefile | 2 +-
> net/ethtool/eeprom.c | 153 +++++++++++++++++++
> net/ethtool/netlink.c | 10 ++
> net/ethtool/netlink.h | 2 +
> 8 files changed, 249 insertions(+), 4 deletions(-)
> create mode 100644 net/ethtool/eeprom.c
>
> diff --git a/Documentation/networking/ethtool-netlink.rst
> b/Documentation/networking/ethtool-netlink.rst
> index 05073482db05..25846b97632a 100644
> --- a/Documentation/networking/ethtool-netlink.rst
> +++ b/Documentation/networking/ethtool-netlink.rst
> @@ -1280,6 +1280,36 @@ Kernel response contents:
> For UDP tunnel table empty ``ETHTOOL_A_TUNNEL_UDP_TABLE_TYPES`` indicates
> that
> the table contains static entries, hard-coded by the NIC.
>
> +EEPROM_DATA
> +===========
> +
> +Fetch module EEPROM data dump.
> +
> +Request contents:
> +
> + ===================================== ====== ==========================
> + ``ETHTOOL_A_EEPROM_DATA_HEADER`` nested request header
> + ``ETHTOOL_A_EEPROM_DATA_OFFSET`` u32 offset within a page
> + ``ETHTOOL_A_EEPROM_DATA_LENGTH`` u32 amount of bytes to read
I wonder if offset and length should be u8. At most, we should only be
returning a 1/2 page, so 128 bytes. We don't need a u32.
> Request translation
> ===================
>
> @@ -1357,8 +1387,8 @@ are netlink only.
> ``ETHTOOL_GET_DUMP_FLAG`` n/a
> ``ETHTOOL_GET_DUMP_DATA`` n/a
> ``ETHTOOL_GET_TS_INFO`` ``ETHTOOL_MSG_TSINFO_GET``
> - ``ETHTOOL_GMODULEINFO`` n/a
> - ``ETHTOOL_GMODULEEEPROM`` n/a
> + ``ETHTOOL_GMODULEINFO`` ``ETHTOOL_MSG_MODULE_EEPROM_GET``
> + ``ETHTOOL_GMODULEEEPROM`` ``ETHTOOL_MSG_MODULE_EEPROM_GET``
> ``ETHTOOL_GEEE`` ``ETHTOOL_MSG_EEE_GET``
> ``ETHTOOL_SEEE`` ``ETHTOOL_MSG_EEE_SET``
> ``ETHTOOL_GRSSH`` n/a
We should check with Michal about this. It is not a direct replacement
of the old IOCTL API, it is new API. He may want it documented
differently.
> +static int eeprom_data_parse_request(struct ethnl_req_info *req_info, struct
> nlattr **tb,
> + struct netlink_ext_ack *extack)
> +{
> + struct eeprom_data_req_info *request = EEPROM_DATA_REQINFO(req_info);
> + struct net_device *dev = req_info->dev;
> +
> + if (!tb[ETHTOOL_A_EEPROM_DATA_OFFSET] ||
> + !tb[ETHTOOL_A_EEPROM_DATA_LENGTH] ||
> + !tb[ETHTOOL_A_EEPROM_DATA_I2C_ADDRESS])
> + return -EINVAL;
> +
> + request->i2c_address =
> nla_get_u8(tb[ETHTOOL_A_EEPROM_DATA_I2C_ADDRESS]);
> + if (request->i2c_address > ETH_MODULE_MAX_I2C_ADDRESS)
> + return -EINVAL;
> +
> + request->offset = nla_get_u32(tb[ETHTOOL_A_EEPROM_DATA_OFFSET]);
> + request->length = nla_get_u32(tb[ETHTOOL_A_EEPROM_DATA_LENGTH]);
> + if (tb[ETHTOOL_A_EEPROM_DATA_PAGE] &&
> + dev->ethtool_ops->get_module_eeprom_data_by_page &&
> + request->offset + request->length > ETH_MODULE_EEPROM_PAGE_LEN)
> + return -EINVAL;
You need to watch out for overflows here. 0xfffffff0 + 0x20 is less
than ETH_MODULE_EEPROM_PAGE_LEN when it wraps around, but will cause
bad things to happen.
Andrew
