From: Henrik Austad haustad@cisco.com
In short summary:
* tsn_core.c is the main driver of tsn, all new links go through here and all data to/form the shims are handled here core also manages the shim-interface.
* tsn_configfs.c is the API to userspace. TSN is driven from userspace and a link is created, configured, enabled, disabled and removed purely from userspace. All attributes requried must be determined by userspace, preferrably via IEEE 1722.1 (discovery and enumeration).
* tsn_header.c small part that handles the actual header of the frames we send. Kept out of core for cleanliness.
* tsn_net.c handles operations towards the networking layer.
The current driver is under development. This means that from the moment it is enabled with a shim, it will send traffic, either 0-traffic (frames of reserved length but with payload 0) or actual traffic. This will change once the driver stabilizes.
For more detail, see Documentation/networking/tsn/
Cc: "David S. Miller" davem@davemloft.net Signed-off-by: Henrik Austad haustad@cisco.com --- net/Makefile | 1 + net/tsn/Makefile | 6 + net/tsn/tsn_configfs.c | 623 +++++++++++++++++++++++++++++++ net/tsn/tsn_core.c | 975 +++++++++++++++++++++++++++++++++++++++++++++++++ net/tsn/tsn_header.c | 203 ++++++++++ net/tsn/tsn_internal.h | 383 +++++++++++++++++++ net/tsn/tsn_net.c | 403 ++++++++++++++++++++ 7 files changed, 2594 insertions(+) create mode 100644 net/tsn/Makefile create mode 100644 net/tsn/tsn_configfs.c create mode 100644 net/tsn/tsn_core.c create mode 100644 net/tsn/tsn_header.c create mode 100644 net/tsn/tsn_internal.h create mode 100644 net/tsn/tsn_net.c
diff --git a/net/Makefile b/net/Makefile index bdd1455..c15482e 100644 --- a/net/Makefile +++ b/net/Makefile @@ -79,3 +79,4 @@ ifneq ($(CONFIG_NET_L3_MASTER_DEV),) obj-y += l3mdev/ endif obj-$(CONFIG_QRTR) += qrtr/ +obj-$(CONFIG_TSN) += tsn/ diff --git a/net/tsn/Makefile b/net/tsn/Makefile new file mode 100644 index 0000000..0d87687 --- /dev/null +++ b/net/tsn/Makefile @@ -0,0 +1,6 @@ +# +# Makefile for the Linux TSN subsystem +# + +obj-$(CONFIG_TSN) += tsn.o +tsn-objs :=tsn_core.o tsn_configfs.o tsn_net.o tsn_header.o diff --git a/net/tsn/tsn_configfs.c b/net/tsn/tsn_configfs.c new file mode 100644 index 0000000..f3d0986 --- /dev/null +++ b/net/tsn/tsn_configfs.c @@ -0,0 +1,623 @@ +/* + * ConfigFS interface to TSN + * Copyright (C) 2015- Henrik Austad haustad@cisco.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/configfs.h> +#include <linux/netdevice.h> +#include <linux/rtmutex.h> +#include <linux/tsn.h> +#include "tsn_internal.h" + +static inline struct tsn_link *to_tsn_link(struct config_item *item) +{ + /* this line causes checkpatch to WARN. making checkpatch happy, + * makes code messy.. + */ + return item ? container_of(to_config_group(item), struct tsn_link, group) : NULL; +} + +static inline struct tsn_nic *to_tsn_nic(struct config_group *group) +{ + return group ? container_of(group, struct tsn_nic, group) : NULL; +} + +/* ----------------------------------------------- + * Tier2 attributes + * + * The content of the links userspace can see/modify + * ----------------------------------------------- +*/ +static ssize_t _tsn_max_payload_size_show(struct config_item *item, + char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%u\n", (u32)link->max_payload_size); +} + +static ssize_t _tsn_max_payload_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + u16 mpl_size = 0; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change Payload size on on enabled link\n"); + return -EINVAL; + } + ret = kstrtou16(page, 0, &mpl_size); + if (ret) + return ret; + + /* 802.1BA-2011 6.4 payload must be <1500 octets (excluding + * headers, tags etc) However, this is not directly mappable to + * how some hw handles things, so to be conservative, we + * restrict it down to [26..1485] + * + * This is also the _payload_ size, which does not include the + * AVTPDU header. This is an upper limit to how much raw data + * the shim can transport in each frame. + */ + if (!tsnh_payload_size_valid(mpl_size, link->shim_header_size)) { + pr_err("%s: payload (%u) should be [26..1480] octets.\n", + __func__, (u32)mpl_size); + return -EINVAL; + } + link->max_payload_size = mpl_size; + return count; +} + +static ssize_t _tsn_shim_header_size_show(struct config_item *item, + char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%u\n", (u32)link->shim_header_size); +} + +static ssize_t _tsn_shim_header_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + u16 hdr_size = 0; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change shim-header size on on enabled link\n"); + return -EINVAL; + } + + ret = kstrtou16(page, 0, &hdr_size); + if (ret) + return ret; + + if (!tsnh_payload_size_valid(link->max_payload_size, hdr_size)) + return -EINVAL; + + link->shim_header_size = hdr_size; + return count; +} + +static ssize_t _tsn_stream_id_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%llu\n", link->stream_id); +} + +static ssize_t _tsn_stream_id_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + u64 sid; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change StreamID on on enabled link\n"); + return -EINVAL; + } + ret = kstrtou64(page, 0, &sid); + if (ret) + return ret; + + if (sid == link->stream_id) + return count; + + if (tsn_find_by_stream_id(sid)) { + pr_warn("Cannot set sid to %llu - exists\n", sid); + return -EEXIST; + } + if (sid != link->stream_id) + tsn_readd_link(link, sid); + return count; +} + +static ssize_t _tsn_buffer_size_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%zu\n", link->buffer_size); +} + +static ssize_t _tsn_buffer_size_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + u32 tmp; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change Buffer Size on on enabled link\n"); + return -EINVAL; + } + + ret = kstrtou32(page, 0, &tmp); + /* only allow buffers !0 and smaller than 8MB for now */ + if (!ret && tmp) { + pr_info("%s: update buffer_size from %zu to %u\n", + __func__, link->buffer_size, tmp); + link->buffer_size = (size_t)tmp; + return count; + } + return -EINVAL; +} + +static ssize_t _tsn_class_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%s\n", (link->class_a ? "A" : "B")); +} + +static ssize_t _tsn_class_store(struct config_item *item, + const char *page, size_t count) +{ + char class[2] = { 0 }; + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change Class-type on on enabled link\n"); + return -EINVAL; + } + if (strncpy(class, page, 1)) { + if (strcmp(class, "a") == 0 || strcmp(class, "A") == 0) + link->class_a = 1; + else if (strcmp(class, "b") == 0 || strcmp(class, "B") == 0) + link->class_a = 0; + return count; + } + + pr_err("%s: Could not copy new class into buffer\n", __func__); + return -EINVAL; +} + +static ssize_t _tsn_vlan_id_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%u\n", link->vlan_id); +} + +static ssize_t _tsn_vlan_id_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + u16 vlan_id; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change VLAN-ID on on enabled link\n"); + return -EINVAL; + } + ret = kstrtou16(page, 0, &vlan_id); + if (ret) + return ret; + if (vlan_id > 0xfff) + return -EINVAL; + link->vlan_id = vlan_id & 0xfff; + return count; +} + +static ssize_t _tsn_pcp_a_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "0x%x\n", link->pcp_a); +} + +static ssize_t _tsn_pcp_a_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + int ret = 0; + u8 pcp; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change PCP-A on enabled link.\n"); + return -EINVAL; + } + ret = kstrtou8(page, 0, &pcp); + if (ret) + return ret; + if (pcp > 0x7) + return -EINVAL; + link->pcp_a = pcp & 0x7; + return count; +} + +static ssize_t _tsn_pcp_b_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "0x%x\n", link->pcp_b); +} + +static ssize_t _tsn_pcp_b_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + int ret = 0; + u8 pcp; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change PCP-B on enabled link.\n"); + return -EINVAL; + } + ret = kstrtou8(page, 0, &pcp); + if (ret) + return ret; + if (pcp > 0x7) + return -EINVAL; + link->pcp_b = pcp & 0x7; + return count; +} + +static ssize_t _tsn_end_station_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%s\n", + (link->estype_talker ? "Talker" : "Listener")); +} + +static ssize_t _tsn_end_station_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + char estype[9] = {0}; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change End-station type on enabled link.\n"); + return -EINVAL; + } + if (strncpy(estype, page, 8)) { + if (strncmp(estype, "Talker", 6) == 0 || + strncmp(estype, "talker", 6) == 0) { + link->estype_talker = 1; + return count; + } else if (strncmp(estype, "Listener", 8) == 0 || + strncmp(estype, "listener", 8) == 0) { + link->estype_talker = 0; + return count; + } + } + return -EINVAL; +} + +static ssize_t _tsn_enabled_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%s\n", tsn_shim_get_active(link)); +} + +static ssize_t _tsn_enabled_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + char driver_type[SHIM_NAME_SIZE] = { 0 }; + struct tsn_shim_ops *shim_ops; + size_t len; + int ret = 0; + + if (!link) + return -EINVAL; + + strncpy(driver_type, page, SHIM_NAME_SIZE - 1); + len = strlen(driver_type); + while (len-- > 0) { + if (driver_type[len] == '\n') + driver_type[len] = 0x00; + } + if (tsn_link_is_on(link)) { + if (strncmp(driver_type, "off", 3) == 0) { + tsn_teardown_link(link); + } else { + pr_err("Unknown value (%s), ignoring\n", driver_type); + return -EINVAL; + } + } else { + shim_ops = tsn_shim_find_by_name(driver_type); + + if (!shim_ops) { + pr_info("%s: could not enable desired shim, %s is not available\n", + __func__, driver_type); + return -EINVAL; + } + + ret = tsn_prepare_link(link, shim_ops); + if (ret != 0) { + pr_err("%s: Trouble perparing link, somethign went wrong - %d\n", + __func__, ret); + return ret; + } + } + return count; +} + +static ssize_t _tsn_remote_mac_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%pM\n", link->remote_mac); +} + +static ssize_t _tsn_remote_mac_store(struct config_item *item, + const char *page, size_t count) +{ + struct tsn_link *link = to_tsn_link(item); + unsigned char mac[6] = {0}; + int ret = 0; + + if (!link) + return -EINVAL; + if (tsn_link_is_on(link)) { + pr_err("ERROR: Cannot change Remote MAC on enabled link.\n"); + return -EINVAL; + } + ret = sscanf(page, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", + &mac[0], &mac[1], &mac[2], &mac[3], &mac[4], &mac[5]); + if (ret > 0) { + pr_info("Got MAC, copying to storage\n"); + memcpy(link->remote_mac, mac, 6); + return count; + } + return -EINVAL; +} + +static ssize_t _tsn_local_mac_show(struct config_item *item, char *page) +{ + struct tsn_link *link = to_tsn_link(item); + + if (!link) + return -EINVAL; + return sprintf(page, "%pMq\n", link->nic->dev->perm_addr); +} + +CONFIGFS_ATTR(_tsn_, max_payload_size); +CONFIGFS_ATTR(_tsn_, shim_header_size); +CONFIGFS_ATTR(_tsn_, stream_id); +CONFIGFS_ATTR(_tsn_, buffer_size); +CONFIGFS_ATTR(_tsn_, class); +CONFIGFS_ATTR(_tsn_, vlan_id); +CONFIGFS_ATTR(_tsn_, pcp_a); +CONFIGFS_ATTR(_tsn_, pcp_b); +CONFIGFS_ATTR(_tsn_, end_station); +CONFIGFS_ATTR(_tsn_, enabled); +CONFIGFS_ATTR(_tsn_, remote_mac); +CONFIGFS_ATTR_RO(_tsn_, local_mac); +static struct configfs_attribute *tsn_tier2_attrs[] = { + &_tsn_attr_max_payload_size, + &_tsn_attr_shim_header_size, + &_tsn_attr_stream_id, + &_tsn_attr_buffer_size, + &_tsn_attr_class, + &_tsn_attr_vlan_id, + &_tsn_attr_pcp_a, + &_tsn_attr_pcp_b, + &_tsn_attr_end_station, + &_tsn_attr_enabled, + &_tsn_attr_remote_mac, + &_tsn_attr_local_mac, + NULL, +}; + +static struct config_item_type group_tsn_tier2_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = tsn_tier2_attrs, + .ct_group_ops = NULL, +}; + +/* ----------------------------------------------- + * Tier1 + * + * The only interesting info at this level are the available links + * belonging to this nic. This will be the subdirectories. Apart from + * making/removing tier-2 folders, nothing else is required here. + */ +static struct config_group *group_tsn_1_make_group(struct config_group *group, + const char *name) +{ + struct tsn_nic *nic = to_tsn_nic(group); + struct tsn_link *link = tsn_create_and_add_link(nic); + + if (!nic || !link) + return ERR_PTR(-ENOMEM); + + config_group_init_type_name(&link->group, name, &group_tsn_tier2_type); + + return &link->group; +} + +static void group_tsn_1_drop_group(struct config_group *group, + struct config_item *item) +{ + struct tsn_link *link = to_tsn_link(item); + struct tsn_nic *nic = to_tsn_nic(group); + + if (link) { + tsn_teardown_link(link); + tsn_remove_link(link); + } + pr_info("Dropping %s from NIC: %s\n", item->ci_name, nic->name); +} + +static struct configfs_attribute *tsn_tier1_attrs[] = { + NULL, +}; + +static struct configfs_group_operations group_tsn_1_group_ops = { + .make_group = group_tsn_1_make_group, + .drop_item = group_tsn_1_drop_group, +}; + +static struct config_item_type group_tsn_tier1_type = { + .ct_group_ops = &group_tsn_1_group_ops, + .ct_attrs = tsn_tier1_attrs, + .ct_owner = THIS_MODULE, +}; + +/* ----------------------------------------------- + * Tier0 + * + * Top level. This will expose all the TSN-capable NICs as well as + * currently active StreamIDs and registered shims. 'Global' info goes + * here. + */ +static ssize_t _tsn_used_sids_show(struct config_item *item, char *page) +{ + return tsn_get_stream_ids(page, PAGE_SIZE); +} + +static ssize_t _tsn_available_shims_show(struct config_item *item, char *page) +{ + return tsn_shim_export_probe_triggers(page); +} + +static struct configfs_attribute tsn_used_sids = { + .ca_owner = THIS_MODULE, + .ca_name = "stream_ids", + .ca_mode = S_IRUGO, + .show = _tsn_used_sids_show, +}; + +static struct configfs_attribute available_shims = { + .ca_owner = THIS_MODULE, + .ca_name = "available_shims", + .ca_mode = S_IRUGO, + .show = _tsn_available_shims_show, +}; + +static struct configfs_attribute *group_tsn_attrs[] = { + &tsn_used_sids, + &available_shims, + NULL, +}; + +static struct config_item_type group_tsn_tier0_type = { + .ct_group_ops = NULL, + .ct_attrs = group_tsn_attrs, + .ct_owner = THIS_MODULE, +}; + +int tsn_configfs_init(struct tsn_list *tlist) +{ + int ret = 0; + struct tsn_nic *next; + struct configfs_subsystem *subsys; + + if (!tlist || !tlist->num_avail) + return -EINVAL; + + /* Tier-0 */ + subsys = &tlist->tsn_subsys; + strncpy(subsys->su_group.cg_item.ci_namebuf, "tsn", + CONFIGFS_ITEM_NAME_LEN); + subsys->su_group.cg_item.ci_type = &group_tsn_tier0_type; + + config_group_init(&subsys->su_group); + mutex_init(&subsys->su_mutex); + + /* Tier-1 + * (tsn-capable NICs), automatic subgroups + */ + list_for_each_entry(next, &tlist->head, list) { + config_group_init_type_name(&next->group, next->name, + &group_tsn_tier1_type); + configfs_add_default_group(&next->group, &subsys->su_group); + } + + /* This is the final step, once done, system is live, make sure + * init has completed properly + */ + ret = configfs_register_subsystem(subsys); + if (ret) { + pr_err("Trouble registering TSN ConfigFS subsystem\n"); + return ret; + } + + pr_warn("configfs_init_module() OK\n"); + return 0; +} + +void tsn_configfs_exit(struct tsn_list *tlist) +{ + if (!tlist) + return; + configfs_unregister_subsystem(&tlist->tsn_subsys); + pr_warn("configfs_exit_module()\n"); +} diff --git a/net/tsn/tsn_core.c b/net/tsn/tsn_core.c new file mode 100644 index 0000000..51f1d13 --- /dev/null +++ b/net/tsn/tsn_core.c @@ -0,0 +1,975 @@ +/* + * TSN Core main part of TSN driver + * + * Copyright (C) 2015- Henrik Austad haustad@cisco.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/rtmutex.h> +#include <linux/hashtable.h> +#include <linux/netdevice.h> +#include <linux/net.h> +#include <linux/dma-mapping.h> +#include <net/sock.h> +#include <net/net_namespace.h> +#include <linux/hrtimer.h> +#include <linux/configfs.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/tsn.h> +#include "tsn_internal.h" + +static struct tsn_list tlist; +static int in_debug; +static int on_cpu = -1; + +#define TLINK_HASH_BITS 8 +DEFINE_HASHTABLE(tlinks, TLINK_HASH_BITS); + +static LIST_HEAD(tsn_shim_ops); + +/* Called with link->lock held */ +static inline size_t _get_low_water(struct tsn_link *link) +{ + /* use max_payload_size and give a rough estimate of how many + * bytes that would be for low_water_ms + */ + int low_water_ms = 20; + int numframes = low_water_ms * 8; + + if (link->class_a) + numframes *= 2; + return link->max_payload_size * numframes; +} + +/* Called with link->lock held */ +static inline size_t _get_high_water(struct tsn_link *link) +{ + size_t low_water = _get_low_water(link); + + return max(link->used_buffer_size - low_water, low_water); +} + +/** + * _tsn_set_buffer - register a memory region to use as the buffer + * + * This is used when we are operating in !external_buffer mode. + * + * TSN expects a ring-buffer and will update pointers to keep track of + * where we are. When the buffer is refilled, head and tail will be + * updated accordingly. + * + * @param link the link that should hold the buffer + * @param buffer the new buffer + * @param bufsize size of new buffer. + * + * @returns 0 on success, negative on error + * + * Must be called with tsn_lock() held. + */ +static int _tsn_set_buffer(struct tsn_link *link, void *buffer, size_t bufsize) +{ + if (link->buffer) { + pr_err("%s: Cannot add buffer, buffer already registred\n", + __func__); + return -EINVAL; + } + + trace_tsn_set_buffer(link, bufsize); + link->buffer = buffer; + link->head = link->buffer; + link->tail = link->buffer; + link->end = link->buffer + bufsize; + link->buffer_size = bufsize; + link->used_buffer_size = bufsize; + return 0; +} + +/** + * _tsn_free_buffer - remove internal buffers + * + * This is the buffer where we store data before shipping it to TSN, or + * where incoming data is staged. + * + * @param link - the link that holds the buffer + * + * Must be called with tsn_lock() held. + */ +static void _tsn_free_buffer(struct tsn_link *link) +{ + if (!link) + return; + trace_tsn_free_buffer(link); + kfree(link->buffer); + link->buffer = NULL; + link->head = NULL; + link->tail = NULL; + link->end = NULL; +} + +int tsn_set_buffer_size(struct tsn_link *link, size_t bsize) +{ + if (!link) + return -EINVAL; + + if (bsize > link->buffer_size) { + pr_err("%s: requested buffer (%zd) larger than allocated memory (%zd)\n", + __func__, bsize, link->buffer_size); + return -ENOMEM; + } + + tsn_lock(link); + link->used_buffer_size = bsize; + link->tail = link->buffer; + link->head = link->buffer; + link->end = link->buffer + link->used_buffer_size; + link->low_water_mark = _get_low_water(link); + link->high_water_mark = _get_high_water(link); + tsn_unlock(link); + + pr_info("Set buffer_size, size: %zd, lowwater: %zd, highwater: %zd\n", + link->used_buffer_size, link->low_water_mark, + link->high_water_mark); + return 0; +} +EXPORT_SYMBOL(tsn_set_buffer_size); + +int tsn_clear_buffer_size(struct tsn_link *link) +{ + if (!link) + return -EINVAL; + + tsn_lock(link); + link->tail = link->buffer; + link->head = link->buffer; + link->end = link->buffer + link->buffer_size; + memset(link->buffer, 0, link->used_buffer_size); + link->used_buffer_size = link->buffer_size; + link->low_water_mark = _get_low_water(link); + link->high_water_mark = _get_high_water(link); + tsn_unlock(link); + return 0; +} +EXPORT_SYMBOL(tsn_clear_buffer_size); + +void *tsn_set_external_buffer(struct tsn_link *link, void *buffer, + size_t buffer_size) +{ + void *old_buffer; + + if (!link) + return NULL; + if (buffer_size < link->max_payload_size) + pr_warn("%s: buffer_size (%zu) < max_payload_size (%u)\n", + __func__, buffer_size, link->max_payload_size); + + tsn_lock(link); + if (!link->external_buffer && link->buffer) + _tsn_free_buffer(link); + + old_buffer = link->buffer; + link->external_buffer = 1; + link->buffer_size = buffer_size; + link->used_buffer_size = buffer_size; + link->buffer = buffer; + link->head = link->buffer; + link->tail = link->buffer; + link->end = link->buffer + link->used_buffer_size; + tsn_unlock(link); + return old_buffer; +} +EXPORT_SYMBOL(tsn_set_external_buffer); + +/* Caller must hold link->lock! + * + * Write data *into* buffer, either from net or from shim due to a + * closing underflow event. + */ +static void __tsn_buffer_write(struct tsn_link *link, void *src, size_t bytes) +{ + int rem = 0; + + /* No Need To Wrap, if overflow we will overwrite without + * warning. + */ + trace_tsn_buffer_write(link, bytes); + if (link->head + bytes < link->end) { + memcpy(link->head, src, bytes); + link->head += bytes; + } else { + rem = link->end - link->head; + memcpy(link->head, src, rem); + memcpy(link->buffer, (src + rem), bytes - rem); + link->head = link->buffer + (bytes - rem); + } +} + +int tsn_buffer_write(struct tsn_link *link, void *src, size_t bytes) +{ + if (!link) + return -EINVAL; + + /* We should not do anything if link has gone inactive */ + if (!tsn_link_is_on(link)) + return 0; + + /* Copied a batch of data and if link is disabled, it is now + * safe to enable it. Otherwise we will continue to send + * null-frames to remote. + */ + if (!tsn_lb(link)) + tsn_lb_enable(link); + + __tsn_buffer_write(link, src, bytes); + + return bytes; +} +EXPORT_SYMBOL(tsn_buffer_write); + +/** + * tsn_buffer_write_net - take data from a skbuff and write it into buffer + * + * When we receive a frame, we grab data from the skbuff and add it to + * link->buffer. + * + * Note that this routine does NOT CARE about channels, samplesize etc, + * it is a _pure_ copy that handles ringbuffer wraps etc. + * + * This function have side-effects as it will update internal tsn_link + * values and trigger refill() should the buffer run low. + * + * NOTE: called from tsn_rx_handler() -> _tsnh_handle_du(), with + * tsn_lock held. + * + * @param link current link that holds the buffer + * @param buffer the buffer to copy from + * @param bytes number of bytes + * @returns Bytes copied into link->buffer, negative value upon error. + */ +int tsn_buffer_write_net(struct tsn_link *link, void *src, size_t bytes) +{ + size_t used; + + if (!link) + return -EINVAL; + + /* Driver has not been enabled yet, i.e. it is in state 'off' and we + * have no way of knowing the state of the buffers. + * Silently drop the data, pretend write went ok + */ + trace_tsn_buffer_write_net(link, bytes); + if (!tsn_lb(link)) + return bytes; + + __tsn_buffer_write(link, src, bytes); + + /* If we stored more data than high_water, we need to drain + * + * In ALSA, this will trigger a snd_pcm_period_elapsed() for the + * substream connected to this particular link. + */ + used = _tsn_buffer_used(link); + if (used > link->high_water_mark) { + trace_tsn_buffer_drain(link, used); + link->ops->buffer_drain(link); + } + + return bytes; +} + +/* caller must hold link->lock! + * + * Read data *from* buffer, either to net or to shim due to a + * closing overflow event. + * + * Function will *not* care if you read past head and into unchartered + * territory, caller must ascertain validity of bytes. + */ +static void __tsn_buffer_read(struct tsn_link *link, void *dst, size_t bytes) +{ + int rem = 0; + + trace_tsn_buffer_read(link, bytes); + if ((link->tail + bytes) < link->end) { + memcpy(dst, link->tail, bytes); + link->tail += bytes; + } else { + rem = link->end - link->tail; + memcpy(dst, link->tail, rem); + memcpy(dst + rem, link->buffer, bytes - rem); + link->tail = link->buffer + bytes - rem; + } +} + +/** + * tsn_buffer_read_net - read data from link->buffer and give to network layer + * + * When we send a frame, we grab data from the buffer and add it to the + * sk_buff->data, this is primarily done by the Tx-subsystem in tsn_net + * and is typically done in small chunks + * + * @param link current link that holds the buffer + * @param buffer the buffer to copy into, must be at least of size bytes + * @param bytes number of bytes. + * + * Note that this routine does NOT CARE about channels, samplesize etc, + * it is a _pure_ copy that handles ringbuffer wraps etc. + * + * This function have side-effects as it will update internal tsn_link + * values and trigger refill() should the buffer run low. + * + * NOTE: expects to be called with locks held + * + * @return Bytes copied into link->buffer, negative value upon error. + */ +int tsn_buffer_read_net(struct tsn_link *link, void *buffer, size_t bytes) +{ + size_t used; + + if (!link) + return -EINVAL; + + /* link is currently inactive, e.g. we send frames, but without + * content + * + * This can be done before we ship data, or if we are muted + * (without expressively stating that over 1722.1 + * + * We do not need to grab any locks here as we won't touch the + * link + */ + if (!tsn_lb(link)) { + memset(buffer, 0, bytes); + goto out; + } + + /* sanity check of bytes to read + * FIXME + */ + + __tsn_buffer_read(link, buffer, bytes); + + /* Trigger refill from client app */ + used = _tsn_buffer_used(link); + if (used < link->low_water_mark) { + trace_tsn_refill(link, used); + link->ops->buffer_refill(link); + } +out: + return bytes; +} + +int tsn_buffer_read(struct tsn_link *link, void *buffer, size_t bytes) +{ + if (!link) + return -EINVAL; + + /* We should not do anything if link has gone inactive */ + if (!tsn_link_is_on(link)) + return 0; + + tsn_lock(link); + __tsn_buffer_read(link, buffer, bytes); + tsn_unlock(link); + return bytes; +} +EXPORT_SYMBOL(tsn_buffer_read); + +static int _tsn_send_batch(struct tsn_link *link) +{ + int ret = 0; + int num_frames = (link->class_a ? 8 : 4); + u64 ts_base_ns = ktime_to_ns(ktime_get()) + (link->class_a ? 2000000 : 50000000); + u64 ts_delta_ns = (link->class_a ? 125000 : 250000); + + trace_tsn_send_batch(link, num_frames, ts_base_ns, ts_delta_ns); + ret = tsn_net_send_set(link, num_frames, ts_base_ns, ts_delta_ns); + if (ret < 0) + pr_err("%s: could not send frame - %d\n", __func__, ret); + + return ret; +} + +static int _tsn_hrtimer_callback(struct tsn_link *link) +{ + int ret = _tsn_send_batch(link); + + if (ret) { + pr_err("%s: Error sending frames (%d), disabling link.\n", + __func__, ret); + tsn_teardown_link(link); + return 0; + } + return 0; +} + +static enum hrtimer_restart tsn_hrtimer_callback(struct hrtimer *hrt) +{ + struct tsn_list *list = container_of(hrt, struct tsn_list, tsn_timer); + struct tsn_link *link; + struct hlist_node *tmp; + int bkt = 0; + + if (!tsn_core_running(list)) + return HRTIMER_NORESTART; + + hrtimer_forward_now(hrt, ns_to_ktime(list->period_ns)); + + hash_for_each_safe(tlinks, bkt, tmp, link, node) { + if (tsn_link_is_on(link) && link->estype_talker) + _tsn_hrtimer_callback(link); + } + + return HRTIMER_RESTART; +} + +static long tsn_hrtimer_init(void *arg) +{ + /* Run every 1ms, _tsn_send_batch will figure out how many + * frames to send for active frames + */ + struct tsn_list *list = (struct tsn_list *)arg; + + hrtimer_init(&list->tsn_timer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL | HRTIMER_MODE_PINNED); + + list->tsn_timer.function = tsn_hrtimer_callback; + hrtimer_cancel(&list->tsn_timer); + atomic_set(&list->running, 1); + + hrtimer_start(&list->tsn_timer, ns_to_ktime(list->period_ns), + HRTIMER_MODE_REL); + return 0; +} + +static void tsn_hrtimer_exit(struct tsn_list *list) +{ + atomic_set(&list->running, 0); + hrtimer_cancel(&list->tsn_timer); +} + +/** + * tsn_prepare_link - prepare link for role as Talker/Receiver + * + * Iow; this will start shipping data through the network-layer. + * + * @link: the actual link + * + * Current status: each link will get a periodic hrtimer that interrupts + * and ships data every 1ms. This will change once we have proper driver + * for hw (i.e. i210 driver). + */ +int tsn_prepare_link(struct tsn_link *link, struct tsn_shim_ops *shim_ops) +{ + int ret = 0; + void *buffer; + u16 framesize; + struct net_device *netdev; + + /* TODO: use separate buckets (lists/rbtrees/whatever) for + * class_a and class_b talker streams. hrtimer-callback should + * not iterate over all. + */ + + if (!link || !shim_ops || !shim_ops->probe) + return -EINVAL; + + pr_info("TSN: allocating buffer, %zd bytes\n", link->buffer_size); + + tsn_lock(link); + + /* configure will calculate idle_slope based on framesize + * (header + payload) + */ + netdev = link->nic->dev; + if (netdev->netdev_ops->ndo_tsn_link_configure) { + framesize = link->max_payload_size + + link->shim_header_size + tsnh_len_all(); + ret = netdev->netdev_ops->ndo_tsn_link_configure(netdev, link->class_a, + framesize, link->vlan_id & 0xfff); + if (ret < 0) + pr_err("Could not configure link - %d\n", ret); + } + + link->ops = shim_ops; + tsn_unlock(link); + ret = link->ops->probe(link); + if (ret != 0) { + pr_err("%s: Could not probe shim (%d), cannot create link\n", + __func__, ret); + link->ops = NULL; + goto out; + } + + tsn_lock(link); + if (!link->external_buffer) { + buffer = kmalloc(link->buffer_size, GFP_KERNEL); + if (!buffer) { + pr_err("%s: Could not allocate memory (%zu) for buffer\n", + __func__, link->buffer_size); + link->ops = NULL; + ret = -ENOMEM; + goto unlock_out; + } + + ret = _tsn_set_buffer(link, buffer, link->buffer_size); + if (ret != 0) { + pr_err("%s: Could not set buffer for TSN, got %d\n", + __func__, ret); + goto unlock_out; + } + } else { + /* FIXME: not handled */ + pr_info("TSN does not currently handle externally hosted buffers. This is on the TODO-list\n"); + ret = -EINVAL; + goto unlock_out; + } + + tsn_link_on(link); + +unlock_out: + tsn_unlock(link); +out: + pr_info("%s: ret=%d\n", __func__, ret); + return ret; +} + +int tsn_teardown_link(struct tsn_link *link) +{ + if (!link) + return -EINVAL; + + tsn_lock(link); + tsn_lb_disable(link); + tsn_link_off(link); + tsn_unlock(link); + + /* Need to call media_close() without (spin-)locks held. + */ + if (link->ops) + link->ops->media_close(link); + + tsn_lock(link); + link->ops = NULL; + _tsn_free_buffer(link); + tsn_unlock(link); + pr_info("%s: disabling all parts of link\n", __func__); + return 0; +} + +int tsn_shim_register_ops(struct tsn_shim_ops *shim_ops) +{ + if (!shim_ops) + return -EINVAL; + + if (!shim_ops->buffer_refill || !shim_ops->buffer_drain || + !shim_ops->media_close || !shim_ops->copy_size || + !shim_ops->validate_header || !shim_ops->assemble_header || + !shim_ops->get_payload_data) + return -EINVAL; + + INIT_LIST_HEAD(&shim_ops->head); + list_add_tail(&shim_ops->head, &tsn_shim_ops); + return 0; +} +EXPORT_SYMBOL(tsn_shim_register_ops); + +void tsn_shim_deregister_ops(struct tsn_shim_ops *shim_ops) +{ + struct tsn_link *link; + struct hlist_node *tmp; + int bkt; + + hash_for_each_safe(tlinks, bkt, tmp, link, node) { + if (!link) + continue; + if (link->ops == shim_ops) + tsn_teardown_link(link); + } + list_del(&shim_ops->head); +} +EXPORT_SYMBOL(tsn_shim_deregister_ops); + +char *tsn_shim_get_active(struct tsn_link *link) +{ + if (!link || !link->ops) + return "off"; + return link->ops->shim_name; +} + +struct tsn_shim_ops *tsn_shim_find_by_name(const char *name) +{ + struct tsn_shim_ops *ops; + + if (!name || list_empty(&tsn_shim_ops)) + return NULL; + + list_for_each_entry(ops, &tsn_shim_ops, head) { + if (strcmp(name, ops->shim_name) == 0) + return ops; + } + return NULL; +} + +ssize_t tsn_shim_export_probe_triggers(char *page) +{ + struct tsn_shim_ops *ops; + ssize_t res = 0; + + if (!page || list_empty(&tsn_shim_ops)) + return 0; + list_for_each_entry(ops, &tsn_shim_ops, head) { + res += snprintf((page + res), PAGE_SIZE - res, "%s\n", + ops->shim_name); + } + return res; +} + +struct tsn_link *tsn_create_and_add_link(struct tsn_nic *nic) +{ + u64 sid = 0; + struct tsn_link *link = kzalloc(sizeof(*link), GFP_KERNEL); + + if (!link) + return NULL; + if (!nic) { + kfree(link); + return NULL; + } + + spin_lock_init(&link->lock); + tsn_lock(link); + tsn_link_off(link); + tsn_lb_disable(link); + do { + sid = prandom_u32(); + sid |= prandom_u32() << 31; + } while (tsn_find_by_stream_id(sid)); + link->stream_id = sid; + + /* There's a slim chance that we actually hit on the first frame + * of data, but if we do, remote seqnr is most likely 0. If this + * is not up to par,, fix in rx_handler + */ + link->last_seqnr = 0xff; + + /* class B audio 48kHz sampling, S16LE, 2ch and IEC61883-6 CIP + * header + */ + link->max_payload_size = 48; + link->shim_header_size = 8; + + /* Default VLAN ID is SR_PVID (2) unless otherwise supplied from + * MSRP, PCP is default 3 for class A, 2 for Class B (See IEEE + * 802.1Q-2011, table 6-6) + */ + link->vlan_id = 0x2; + link->pcp_a = 3; + link->pcp_b = 2; + link->class_a = 0; + + link->buffer_size = 16536; + /* default: talker since listener isn't implemented yet. */ + link->estype_talker = 1; + + link->nic = nic; + tsn_unlock(link); + + /* Add the newly created link to the hashmap of all active links. + * + * test if sid is present in hashmap already (barf on that) + */ + + mutex_lock(&tlist.lock); + hash_add(tlinks, &link->node, link->stream_id); + mutex_unlock(&tlist.lock); + pr_info("%s: added link with stream_id: %llu\n", + __func__, link->stream_id); + + return link; +} + +ssize_t tsn_get_stream_ids(char *page, ssize_t len) +{ + struct tsn_link *link; + struct hlist_node *tmp; + char *buffer = page; + int bkt; + + if (!page) + return 0; + + if (hash_empty(tlinks)) + return sprintf(buffer, "no links registered\n"); + + hash_for_each_safe(tlinks, bkt, tmp, link, node) + buffer += sprintf(buffer, "%llu\n", link->stream_id); + + return (buffer - page); +} + +struct tsn_link *tsn_find_by_stream_id(u64 sid) +{ + struct tsn_link *link; + + if (hash_empty(tlinks)) + return 0; + + hash_for_each_possible(tlinks, link, node, sid) { + if (link->stream_id == sid) + return link; + } + + return NULL; +} + +void tsn_remove_link(struct tsn_link *link) +{ + if (!link) + return; + tsn_net_close(link); + mutex_lock(&tlist.lock); + hash_del(&link->node); + if (link->ops) { + link->ops->media_close(link); + link->ops = NULL; + } + + mutex_unlock(&tlist.lock); +} + +void tsn_readd_link(struct tsn_link *link, u64 newkey) +{ + if (!link) + return; + tsn_lock(link); + if (hash_hashed(&link->node)) { + pr_info("%s: updating link with stream_id %llu -> %llu\n", + __func__, link->stream_id, newkey); + tsn_remove_link(link); + } + + link->stream_id = newkey; + tsn_unlock(link); + + hash_add(tlinks, &link->node, link->stream_id); +} + +static int _tsn_capable_nic(struct net_device *netdev, struct tsn_nic *nic) +{ + if (!nic || !netdev || !netdev->netdev_ops || + !netdev->netdev_ops->ndo_tsn_capable) + return -EINVAL; + + if (netdev->netdev_ops->ndo_tsn_capable(netdev) > 0) + nic->capable = 1; + + return 0; +} + +/* Identify all TSN-capable NICs in the system + */ +static int tsn_nic_probe(void) +{ + struct net *net; + struct net_device *netdev; + struct tsn_nic *nic; + + net = &init_net; + rcu_read_lock(); + for_each_netdev_rcu(net, netdev) { + pr_info("Found %s, alias %s on irq %d\n", + netdev->name, + netdev->ifalias, + netdev->irq); + pr_info("MAC: %pM", netdev->dev_addr); + if (netdev->tx_queue_len) + pr_info("Tx queue length: %lu\n", netdev->tx_queue_len); + nic = kzalloc(sizeof(*nic), GFP_KERNEL); + if (!nic) { + pr_err("Could not allocate memory for tsn_nic!\n"); + return -ENOMEM; + } + nic->dev = netdev; + nic->txq = netdev->num_tx_queues; + nic->name = netdev->name; + nic->tsn_list = &tlist; + nic->dma_size = 1048576; + + _tsn_capable_nic(netdev, nic); + + /* if not capable and we are not in debug-mode, drop nic + * and continue + */ + if (!nic->capable && !in_debug) { + pr_info("Invalid capabilities for NIC (%s), dropping from TSN list\n", + netdev->name); + kfree(nic); + continue; + } + + INIT_LIST_HEAD(&nic->list); + mutex_lock(&tlist.lock); + list_add_tail(&nic->list, &tlist.head); + tlist.num_avail++; + mutex_unlock(&tlist.lock); + } + rcu_read_unlock(); + + return 0; +} + +static void tsn_free_nic_list(struct tsn_list *list) +{ + struct tsn_nic *tmp, *next; + + mutex_lock(&list->lock); + list_for_each_entry_safe(tmp, next, &list->head, list) { + pr_info("Dropping %s from list\n", tmp->dev->name); + list_del(&tmp->list); + tmp->dev = NULL; + kfree(tmp); + } + mutex_unlock(&list->lock); +} + +/* all active links are stored in hashmap 'tlinks' + */ +static void tsn_remove_all_links(void) +{ + int bkt; + struct tsn_link *link; + struct hlist_node *tmp; + + hash_for_each_safe(tlinks, bkt, tmp, link, node) { + pr_info("%s removing a link\n", __func__); + if (!tsn_teardown_link(link)) + tsn_remove_link(link); + } + + pr_info("%s: all links have been removed\n", __func__); +} + +static int __init tsn_init_module(void) +{ + int ret = 0; + + INIT_LIST_HEAD(&tlist.head); + mutex_init(&tlist.lock); + + atomic_set(&tlist.running, 0); + tlist.period_ns = 1000000; + + /* Find all NICs, attach a rx-handler for sniffing out TSN + * traffic on *all* of them. + */ + tlist.num_avail = 0; + ret = tsn_nic_probe(); + if (ret < 0) { + pr_err("%s: somethign went awry whilst probing for NICs, aborting\n", + __func__); + goto out; + } + + if (!tlist.num_avail) { + pr_err("%s: No capable NIC found. Perhaps load with in_debug=1 ?\n", + __func__); + ret = -EINVAL; + goto out; + } + + /* register Rx-callbacks for all (valid) NICs */ + ret = tsn_net_add_rx(&tlist); + if (ret < 0) { + pr_err("%s: Could add Rx-handler, aborting\n", __func__); + goto error_rx_out; + } + + /* init DMA regions etc */ + ret = tsn_net_prepare_tx(&tlist); + if (ret < 0) { + pr_err("%s: could not prepare Tx, aborting\n", __func__); + goto error_tx_out; + } + + /* init hashtable */ + hash_init(tlinks); + + /* init configfs */ + ret = tsn_configfs_init(&tlist); + if (ret < 0) { + pr_err("%s: Could not initialize configfs properly (%d), aborting\n", + __func__, ret); + goto error_cfs_out; + } + + /* Test to see if on_cpu is available */ + if (on_cpu >= 0) { + pr_info("%s: pinning timer on CPU %d\n", __func__, on_cpu); + ret = work_on_cpu(on_cpu, tsn_hrtimer_init, &tlist); + if (ret != 0) { + pr_err("%s: could not init hrtimer properly on CPU %d, aborting\n", + __func__, on_cpu); + goto error_hrt_out; + } + } else { + ret = tsn_hrtimer_init(&tlist); + if (ret < 0) { + pr_err("%s: could not init hrtimer properly, aborting\n", + __func__); + goto error_hrt_out; + } + } + pr_info("TSN subsystem init OK\n"); + return 0; + +error_hrt_out: + tsn_remove_all_links(); + tsn_configfs_exit(&tlist); +error_cfs_out: + tsn_net_disable_tx(&tlist); +error_tx_out: + tsn_net_remove_rx(&tlist); +error_rx_out: + tsn_free_nic_list(&tlist); +out: + return ret; +} + +static void __exit tsn_exit_module(void) +{ + pr_warn("removing module TSN\n"); + tsn_hrtimer_exit(&tlist); + + tsn_remove_all_links(); + tsn_configfs_exit(&tlist); + + /* Unregister Rx-handlers if set */ + tsn_net_remove_rx(&tlist); + + tsn_net_disable_tx(&tlist); + + tsn_free_nic_list(&tlist); + + pr_warn("TSN exit\n"); +} +module_param(in_debug, int, S_IRUGO); +module_param(on_cpu, int, S_IRUGO); +module_init(tsn_init_module); +module_exit(tsn_exit_module); +MODULE_AUTHOR("Henrik Austad"); +MODULE_LICENSE("GPL"); diff --git a/net/tsn/tsn_header.c b/net/tsn/tsn_header.c new file mode 100644 index 0000000..a0d31c5 --- /dev/null +++ b/net/tsn/tsn_header.c @@ -0,0 +1,203 @@ +/* + * Network header handling for TSN + * + * Copyright (C) 2015- Henrik Austad haustad@cisco.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/tsn.h> +#include <trace/events/tsn.h> + +#include "tsn_internal.h" + +#define AVTP_GPTP_TIMEMASK 0xFFFFFFFF + +static u32 tsnh_avtp_timestamp(u64 ptime_ns) +{ + /* See 1722-2011, 5.4.8 + * + * (AS_sec * 1e9 + AS_ns) % 2^32 + * + * Just use ktime_get_ns() and grab lower 32 bits of it. + */ + /* u64 ns = ktime_to_ns(ktime_get()); */ + u32 gptp_ts = ptime_ns & AVTP_GPTP_TIMEMASK; + return gptp_ts; +} + +int tsnh_ch_init(struct avtp_ch *header) +{ + if (!header) + return -EINVAL; + header = memset(header, 0, sizeof(*header)); + + /* This should be changed when setting control / data + * content. Set to experimental to allow for strange content + * should callee not do job properly + */ + header->subtype = AVTP_EXPERIMENTAL; + + header->version = 0; + return 0; +} + +int _tsnh_validate_du_header(struct tsn_link *link, struct avtp_ch *ch, + struct sk_buff *skb) +{ + struct avtpdu_header *header = (struct avtpdu_header *)ch; + struct sockaddr_ll *sll; + u16 bytes; + u8 seqnr; + + if (ch->cd) + return -EINVAL; + + /* As a minimum, we should match the sender's MAC to the + * expected MAC before we pass the frame along. + * + * This does not give much in the way of security (a malicious + * user could probably fake this), but it should remove most + * accidents. + */ + sll = (struct sockaddr_ll *)&skb->cb; + sll->sll_halen = dev_parse_header(skb, sll->sll_addr); + if (sll->sll_halen != 6) { + trace_printk("%s: received MAC address length mismatch. Expected 6 bytes, got %d\n", + __func__, sll->sll_halen); + return -EPROTO; + } + + if (memcmp(link->remote_mac, &sll->sll_addr, 6)) { + trace_printk("%s: received MAC-address mismatch (expected %pM, got %pM), dropping frame\n", + __func__, link->remote_mac, &sll->sll_addr); + return -EPROTO; + } + + /* Current iteration of TSNis 0b000 only */ + if (ch->version) + return -EPROTO; + + /* Invalid StreamID, should not have ended up here in the first + * place (since we do DU only), if invalid sid, how did we find + * the link? + */ + if (!ch->sv) + return -EPROTO; + + /* Check seqnr, if we have lost one frame, we _could_ insert an + * empty frame, but since we have frame-guarantee from 802.1Qav, + * we don't + */ + seqnr = (link->last_seqnr + 1) & 0xff; + if (header->seqnr != seqnr) { + trace_printk("%llu: seqnr mismatch. Got %u, expected %u\n", + link->stream_id, header->seqnr, seqnr); + return -EPROTO; + } + + bytes = ntohs(header->sd_len); + if (bytes == 0 || bytes > link->max_payload_size) { + trace_printk("%llu: payload size larger than expected (%u, expected %u)\n", + link->stream_id, bytes, link->max_payload_size); + return -EINVAL; + } + + /* let shim validate header here as well */ + if (link->ops->validate_header && + link->ops->validate_header(link, header) != 0) + return -EINVAL; + + return 0; +} + +int tsnh_assemble_du(struct tsn_link *link, struct avtpdu_header *header, + size_t bytes, u64 ts_pres_ns) +{ + int ret = 0; + void *data; + + if (!header || !link) + return -EINVAL; + + tsnh_ch_init((struct avtp_ch *)header); + header->cd = 0; + header->sv = 1; + header->mr = 0; + header->gv = 0; + header->tv = 1; + header->tu = 0; + header->avtp_timestamp = htonl(tsnh_avtp_timestamp(ts_pres_ns)); + header->gateway_info = 0; + header->sd_len = htons(bytes); + + tsn_lock(link); + if (!link->ops) { + pr_err("%s: No available ops, cannot assemble data-unit\n", + __func__); + ret = -EINVAL; + goto unlock_out; + } + /* get pointer to where data starts */ + data = link->ops->get_payload_data(link, header); + + if (bytes > link->used_buffer_size) { + pr_err("bytes > buffer_size (%zd > %zd)\n", + bytes, link->used_buffer_size); + ret = -EINVAL; + goto unlock_out; + } + + header->stream_id = cpu_to_be64(link->stream_id); + header->seqnr = link->last_seqnr++; + link->ops->assemble_header(link, header, bytes); + tsn_unlock(link); + + /* payload */ + ret = tsn_buffer_read_net(link, data, bytes); + if (ret != bytes) { + pr_err("%s: Could not copy %zd bytes of data. Res: %d\n", + __func__, bytes, ret); + /* FIXME: header cleanup */ + goto out; + } + ret = 0; +out: + return ret; +unlock_out: + tsn_unlock(link); + return ret; +} + +int _tsnh_handle_du(struct tsn_link *link, struct avtp_ch *ch) +{ + struct avtpdu_header *header = (struct avtpdu_header *)ch; + void *data; + u16 bytes; + int ret; + + bytes = ntohs(header->sd_len); + + trace_tsn_du(link, bytes); + /* bump seqnr */ + data = link->ops->get_payload_data(link, header); + if (!data) + return -EINVAL; + + link->last_seqnr = header->seqnr; + ret = tsn_buffer_write_net(link, data, bytes); + if (ret != bytes) { + trace_printk("%s: Could not copy %u bytes of data. Res: %d\n", + __func__, bytes, ret); + return ret; + } + + return 0; +} diff --git a/net/tsn/tsn_internal.h b/net/tsn/tsn_internal.h new file mode 100644 index 0000000..d0d2201 --- /dev/null +++ b/net/tsn/tsn_internal.h @@ -0,0 +1,383 @@ +/* + * Copyright (C) 2015- Henrik Austad haustad@cisco.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#ifndef _TSN_INTERNAL_H_ +#define _TSN_INTERNAL_H_ +#include <linux/tsn.h> + +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/if_ether.h> +#include <linux/if_vlan.h> + +/* TODO: + * - hide tsn-structs and provide handlers + * - decouple config/net from core + */ + +struct avtpdu_header; +struct tsn_link; +struct tsn_shim_ops; + +#define IS_TSN_FRAME(x) (ntohs(x) == ETH_P_TSN) +#define IS_PTP_FRAME(x) (ntohs(x) == ETH_P_1588) +#define IS_1Q_FRAME(x) (ntohs(x) == ETH_P_8021Q) + +/** + * tsn_add_link - create and add a new link to the system + * + * Note: this will not enable the link, just allocate most of the data + * required for the link. One notable exception being the buffer as we + * can modify the buffersize before we start the link. + * + * @param nic : the nic the link is tied to + * @returns the new link + */ +struct tsn_link *tsn_create_and_add_link(struct tsn_nic *nic); + +/** + * tsn_get_stream_ids - write all current Stream IDs into the page. + * + * @param page the page to write into + * @param len size of page + * @returns the number of bytes written + */ +ssize_t tsn_get_stream_ids(char *page, ssize_t len); + +/** + * tsn_find_by_stream_id - given a sid, find the corresponding link + * + * @param sid stream_id + * @returns tsn_link struct or NULL if not found + */ +struct tsn_link *tsn_find_by_stream_id(u64 sid); + +/** + * tsn_readd_link - make sure a link is moved to the correct bucket when + * stream_id is updated + * + * @link the TSN link + * @old_key previous key for which it can be located in the hashmap + * + */ +void tsn_readd_link(struct tsn_link *link, u64 old_key); + +/** + * tsn_remove_link: cleanup and remove from internal storage + * + * @link: the link to be removed + */ +void tsn_remove_link(struct tsn_link *link); + +/** + * tsn_prepare_link - make link ready for usage + * + * Caller is happy with the different knobs, this will create the link and start + * pushing the data. + * + * Requirement: + * - callback registered + * - State set to either Talker or Listener + * + * @param active link + * @param the shim_ops to use for the new link + * @return 0 on success, negative on error + */ +int tsn_prepare_link(struct tsn_link *link, struct tsn_shim_ops *shim_ops); +int tsn_teardown_link(struct tsn_link *link); + +/** + * tsn_set_external_buffer - force an update of the buffer + * + * This will cause tsn_core to use an external buffer. If external + * buffering is already in use, this has the effect of forcing an update + * of the buffer. + * + * This will cause tsn_core to swap buffers. The current buffer is + * returned and the new is used in place. + * + * Note: If the new buffer is NULL or buffer_size is less than + * max_payload_size, the result can be interesting (by calling this + * function, you claim to know what you are doing and should pass sane + * values). + * + * This can also be used if you need to resize the buffer in use. + * + * Core will continue to use the tsn_shim_swap when the new buffer is + * full. + * + * @param link current link owning the buffer + * @param buffer new buffer to use + * @param buffer_size size of new buffer + * @return old buffer + */ +void *tsn_set_external_buffer(struct tsn_link *link, void *buffer, + size_t buffer_size); + +/** + * tsn_buffer_write_net - write data *into* link->buffer from the network layer + * + * Used by tsn_net and will typicall accept very small pieces of data. + * + * @param link the link associated with the stream_id in the frame + * @param src pointer to data in buffer + * @param bytes number of bytes to copy + * @return number of bytes copied into the buffer + */ +int tsn_buffer_write_net(struct tsn_link *link, void *src, size_t bytes); + +/** + * tsn_buffer_read_net - read data from link->buffer and give to network layer + * + * When we send a frame, we grab data from the buffer and add it to the + * sk_buff->data, this is primarily done by the Tx-subsystem in tsn_net + * and is typically done in small chunks + * + * @param link current link that holds the buffer + * @param buffer the buffer to copy into, must be at least of size bytes + * @param bytes number of bytes. + * + * Note that this routine does NOT CARE about channels, samplesize etc, + * it is a _pure_ copy that handles ringbuffer wraps etc. + * + * This function have side-effects as it will update internal tsn_link + * values and trigger refill() should the buffer run low. + * + * @return Bytes copied into link->buffer, negative value upon error. + */ +int tsn_buffer_read_net(struct tsn_link *link, void *buffer, size_t bytes); + +/** + * tsn_core_running(): test if the link is running + * + * By running, we mean that it is configured and a proper shim has been + * loaded. It does *not* mean that we are currently pushing data in any + * direction, see tsn_net_buffer_disabled() for this + * + * @param struct tsn_link active link + * @returns 1 if core is running + */ +static inline int tsn_core_running(struct tsn_list *list) +{ + if (list) + return atomic_read(&list->running); + return 0; +} + +/** + * _tsn_buffer_used - how much of the buffer is filled with valid data + * + * - assumes link->running in state running + * - will ignore change changed state + * + * We write to head, read from tail. + */ +static inline size_t _tsn_buffer_used(struct tsn_link *link) +{ + return (link->head - link->tail) % link->used_buffer_size; +} + +static inline void tsn_lock(struct tsn_link *link) +{ + spin_lock(&link->lock); +} + +static inline void tsn_unlock(struct tsn_link *link) +{ + spin_unlock(&link->lock); +} + +/* ----------------------------- + * ConfigFS handling + */ +int tsn_configfs_init(struct tsn_list *tlist); +void tsn_configfs_exit(struct tsn_list *tlist); + +/* ----------------------------- + * TSN Header + */ + +static inline size_t tsnh_len(void) +{ + /* include 802.1Q tag */ + return sizeof(struct avtpdu_header); +} + +static inline u16 tsnh_len_all(void) +{ + return (u16)tsnh_len() + ETH_HLEN; +} + +/** + * tsnh_payload_size_valid - if the entire payload is within size-limit + * + * Ensure that max_payload_size and shim_header_size is within acceptable limits + * + * We need both values to calculate the payload size when reserving + * bandwidth, but only payload-size when instructing the shim to copy + * out data for us. + * + * @param max_payload_size requested payload to send in each frame (upper limit) + * @return 0 on invalid, 1 on valid + */ +static inline int tsnh_payload_size_valid(u16 max_payload_size, + u16 shim_hdr_size) +{ + /* VLAN_ETH_ZLEN 64 */ + /* VLAN_ETH_FRAME_LEN 1518 */ + u32 framesize = max_payload_size + tsnh_len_all() + shim_hdr_size; + + return framesize >= VLAN_ETH_ZLEN && framesize <= VLAN_ETH_FRAME_LEN; +} + +/** + * _tsnh_validate_du_header - basic header validation + * + * This expects the parameters to be present and the link-lock to be + * held. + * + * @param header header to verify + * @param link owner of stream + * @param socket_buffer + * @return 0 on valid, negative on invalid/error + */ +int _tsnh_validate_du_header(struct tsn_link *link, struct avtp_ch *ch, + struct sk_buff *skb); + +/** + * tsnh_assemble_du - assemble header and copy data from buffer + * + * This function will initialize the header and pass final init to + * shim->assemble_header before copying data into the buffer. + * + * It assumes that 'bytes' is a sane value, i.e. that it is a valid + * multiple of number of channels, sample size etc. + * + * @param link Current TSN link, also holds the buffer + * + * @param header header to assemble for data + * + * @param bytes Number of bytes to send in this frame + * + * @param ts_pres_ns current for when the frame should be presented or + * considered valid by the receiving end. In + * nanoseconds since epoch, will be converted to gPTP + * compatible timestamp. + * + * @return 0 on success, negative on error + */ +int tsnh_assemble_du(struct tsn_link *link, struct avtpdu_header *header, + size_t bytes, u64 ts_pres_ns); + +/** + * _tsnh_handle_du - handle incoming data and store to media-buffer + * + * This assumes that the frame actually belongs to the link and that it + * has passed basic validation. + * + * It also expects the link lock to be held. + * + * @param link Link associated with stream_id + * @param header Header of incoming frame + * @return number of bytes copied to buffer or negative on error + */ +int _tsnh_handle_du(struct tsn_link *link, struct avtp_ch *ch); + +static inline struct avtp_ch *tsnh_ch_from_skb(struct sk_buff *skb) +{ + if (!skb) + return NULL; + if (!IS_TSN_FRAME(eth_hdr(skb)->h_proto)) + return NULL; + + return (struct avtp_ch *)skb->data; +} + +/** + * tsn_net_add_rx - add Rx handler for all NICs listed + * + * @param list tsn_list to add Rx handler to + * @return 0 on success, negative on error + */ +int tsn_net_add_rx(struct tsn_list *list); + +/** + * tsn_net_remove_rx - remove Rx-handlers for all tsn_nics + * + * Go through all NICs and remove those Rx-handlers we have + * registred. If someone else has added an Rx-handler to the NIC, we do + * not touch it. + * + * @param list list of all tsn_nics (with links) + */ +void tsn_net_remove_rx(struct tsn_list *list); + +/** + * tsn_net_open_tx - prepare all capable links for Tx + * + * This will prepare all NICs for Tx, and those marked as 'capable' + * will be initialized with DMA regions. Note that this is not the final + * step for preparing for Tx, it is only when we have active links that + * we know how much bandwidth we need and then can set the appropriate + * idleSlope params etc. + * + * @tlist: list of all available card + * @return: negative on error, on success the number of prepared NICS + * are returned. + */ +int tsn_net_prepare_tx(struct tsn_list *tlist); + +/** + * tsn_net_disable_tx - disable Tx on card + * + * This frees DMA-memory from capable NICs + * + * @param tsn_list: link to all available NICs used by TSN + */ +void tsn_net_disable_tx(struct tsn_list *tlist); + +/** + * tsn_net_set_vlan - try to register the VLAN on the NIC + * + * Some NICs will handle VLAN themselves, try to register this vlan with + * the card to enable hw-support for Tx via this VLAN + * + * @param: tsn_link the active link + * @return: 0 on success, negative on error. + */ +int tsn_net_set_vlan(struct tsn_link *link); + +/** + * tsn_net_close - close down link properly + * + * @param struct tsn_link * active link to close down + */ +void tsn_net_close(struct tsn_link *link); + +/** + * tsn_net_send_set - send a set of frames + * + * We want to assemble a number of sk_buffs at a time and ship them off + * in a single go and then go back to sleep. Pacing should be done by + * hardware, or if we are in in_debug, we don't really care anyway + * + * @param link : current TSN-link + * @param num : the number of frames to create + * @param ts_base_ns : base timestamp for when the frames should be + * considered valid + * @param ts_delta_ns : time between each frame in the set + */ +int tsn_net_send_set(struct tsn_link *link, size_t num, u64 ts_base_ns, + u64 ts_delta_ns); + +#endif /* _TSN_INTERNAL_H_ */ diff --git a/net/tsn/tsn_net.c b/net/tsn/tsn_net.c new file mode 100644 index 0000000..560e2fd --- /dev/null +++ b/net/tsn/tsn_net.c @@ -0,0 +1,403 @@ +/* + * Network part of TSN + * + * Copyright (C) 2015- Henrik Austad haustad@cisco.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/socket.h> +#include <linux/skbuff.h> +#include <linux/if_vlan.h> +#include <linux/skbuff.h> +#include <net/sock.h> + +#include <linux/tsn.h> +#include <trace/events/tsn.h> +#include "tsn_internal.h" + +/** + * tsn_rx_handler - consume all TSN-tagged frames and forward to tsn_link. + * + * This handler, if it regsters properly, will consume all TSN-tagged + * frames belonging to registered Stream IDs + * + * Unknown StreamIDs will be passed through without being touched. + * + * @param pskb sk_buff with incomign data + * @returns RX_HANDLER_CONSUMED for TSN frames to known StreamIDs, + * RX_HANDLER_PASS for everything else. + */ +static rx_handler_result_t tsn_rx_handler(struct sk_buff **pskb) +{ + struct sk_buff *skb = *pskb; + const struct ethhdr *ethhdr = eth_hdr(skb); + struct avtp_ch *ch; + struct tsn_link *link; + rx_handler_result_t ret = RX_HANDLER_PASS; + + ch = tsnh_ch_from_skb(skb); + if (!ch) + return RX_HANDLER_PASS; + /* We do not (currently) touch control_data frames. */ + if (ch->cd) + return RX_HANDLER_PASS; + + link = tsn_find_by_stream_id(be64_to_cpu(ch->stream_id)); + if (!link) + return RX_HANDLER_PASS; + + tsn_lock(link); + + if (!tsn_link_is_on(link)) + goto out_unlock; + + /* If link->ops is not set yet, there's nothing we can do, just + * ignore this frame + */ + if (!link->ops) + goto out_unlock; + + if (_tsnh_validate_du_header(link, ch, skb)) + goto out_unlock; + + trace_tsn_rx_handler(link, ethhdr, be64_to_cpu(ch->stream_id)); + + /* Handle dataunit, if it failes, pass on the frame and let + * userspace pick it up. + */ + if (_tsnh_handle_du(link, ch) < 0) + goto out_unlock; + + /* Done, data has been copied, free skb and return consumed */ + consume_skb(skb); + ret = RX_HANDLER_CONSUMED; + +out_unlock: + tsn_unlock(link); + return ret; +} + +int tsn_net_add_rx(struct tsn_list *tlist) +{ + struct tsn_nic *nic; + + if (!tlist) + return -EINVAL; + + /* Setup receive handler for TSN traffic. + * + * Receive will happen all the time, once a link is active as a + * Listener, we will add a hook into the receive-handler to + * steer the frames to the correct link. + * + * We try to add Rx-handlers to all the card listed in tlist (we + * assume core has filtered the NICs appropriatetly sothat only + * TSN-capable cards are present). + */ + mutex_lock(&tlist->lock); + list_for_each_entry(nic, &tlist->head, list) { + rtnl_lock(); + if (netdev_rx_handler_register(nic->dev, tsn_rx_handler, nic) < 0) { + pr_err("%s: could not attach an Rx-handler to %s, this link will not be able to accept TSN traffic\n", + __func__, nic->name); + rtnl_unlock(); + continue; + } + rtnl_unlock(); + pr_info("%s: attached rx-handler to %s\n", + __func__, nic->name); + nic->rx_registered = 1; + } + mutex_unlock(&tlist->lock); + return 0; +} + +void tsn_net_remove_rx(struct tsn_list *tlist) +{ + struct tsn_nic *nic; + + if (!tlist) + return; + mutex_lock(&tlist->lock); + list_for_each_entry(nic, &tlist->head, list) { + rtnl_lock(); + if (nic->rx_registered) + netdev_rx_handler_unregister(nic->dev); + rtnl_unlock(); + nic->rx_registered = 0; + pr_info("%s: RX-handler for %s removed\n", + __func__, nic->name); + } + mutex_unlock(&tlist->lock); +} + +int tsn_net_prepare_tx(struct tsn_list *tlist) +{ + struct tsn_nic *nic; + struct device *dev; + int ret = 0; + + if (!tlist) + return -EINVAL; + + mutex_lock(&tlist->lock); + list_for_each_entry(nic, &tlist->head, list) { + if (!nic) + continue; + if (!nic->capable) + continue; + + if (!nic->dev->netdev_ops) + continue; + + dev = nic->dev->dev.parent; + nic->dma_mem = dma_alloc_coherent(dev, nic->dma_size, + &nic->dma_handle, GFP_KERNEL); + if (!nic->dma_mem) { + nic->capable = 0; + nic->dma_size = 0; + continue; + } + ret++; + } + mutex_unlock(&tlist->lock); + pr_info("%s: configured %d cards to use DMA\n", __func__, ret); + return ret; +} + +void tsn_net_disable_tx(struct tsn_list *tlist) +{ + struct tsn_nic *nic; + struct device *dev; + int res = 0; + + if (!tlist) + return; + mutex_lock(&tlist->lock); + list_for_each_entry(nic, &tlist->head, list) { + if (nic->capable && nic->dma_mem) { + dev = nic->dev->dev.parent; + dma_free_coherent(dev, nic->dma_size, nic->dma_mem, + nic->dma_handle); + res++; + } + } + mutex_unlock(&tlist->lock); + pr_info("%s: freed DMA regions from %d cards\n", __func__, res); +} + +void tsn_net_close(struct tsn_link *link) +{ + /* struct tsn_rx_handler_data *rx_data; */ + + /* Careful! we need to make sure that we actually succeeded in + * registering the handler in open unless we want to unregister + * some random rx_handler.. + */ + if (!link->estype_talker) { + ; + /* Make sure we notify rx-handler so it doesn't write + * into NULL + */ + } +} + +int tsn_net_set_vlan(struct tsn_link *link) +{ + int err; + struct tsn_nic *nic = link->nic; + const struct net_device_ops *ops = nic->dev->netdev_ops; + + int vf = 2; + u16 vlan = link->vlan_id; + u8 qos = link->class_a ? link->pcp_a : link->pcp_b; + + pr_info("%s:%s Setting vlan=%u,vf=%d,qos=%u\n", + __func__, nic->name, vlan, vf, qos); + if (ops->ndo_set_vf_vlan) { + err = ops->ndo_set_vf_vlan(nic->dev, vf, vlan, qos); + if (err != 0) { + pr_err("%s:%s could not set VLAN to %u, got %d\n", + __func__, nic->name, vlan, err); + return -EINVAL; + } + return 0; + } + return -1; +} + +static inline u16 _get_8021q_vid(struct tsn_link *link) +{ + u16 pcp = link->class_a ? link->pcp_a : link->pcp_b; + /* If not explicitly provided, use SR_PVID 0x2*/ + return (link->vlan_id & VLAN_VID_MASK) | ((pcp & 0x7) << 13); +} + +/* create and initialize a sk_buff with appropriate TSN Header values + * + * layout of frame: + * - Ethernet header + * dst (6) | src (6) | 802.1Q (4) | EtherType (2) + * - 1722 (sizeof struct avtpdu) + * - payload data + * - type header (e.g. iec61883-6 hdr) + * - payload data + * + * Required size: + * Ethernet: 18 -> VLAN_ETH_HLEN + * 1722: tsnh_len() + * payload: shim_hdr_size + data_bytes + * + * Note: + * - seqnr is not set + * - payload is not set + */ +static struct sk_buff *_skbuf_create_init(struct tsn_link *link, + size_t data_bytes, + size_t shim_hdr_size, + u64 ts_pres_ns, u8 more) +{ + struct sk_buff *skb = NULL; + struct avtpdu_header *avtpdu; + struct net_device *netdev = link->nic->dev; + int queue_idx; + int res = 0; + int hard_hdr_len; + + /* length is size of AVTPDU + data + * +-----+ <-- head + * | - link layer header + * | - 1722 header (avtpdu_header) + * +-----+ <-- data + * | - shim_header + * | - data + * +-----+ <-- tail + * | + * +-----+ <--end + * We stuff all of TSN-related + * headers in the data-segment to make it easy + */ + size_t hdr_len = VLAN_ETH_HLEN; + size_t avtpdu_len = tsnh_len() + shim_hdr_size + data_bytes; + + skb = alloc_skb(hdr_len + avtpdu_len + netdev->needed_tailroom, + GFP_ATOMIC | GFP_DMA); + if (!skb) + return NULL; + skb_reserve(skb, hdr_len); + + skb->protocol = htons(ETH_P_TSN); + skb->pkt_type = PACKET_OUTGOING; + skb->priority = (link->class_a ? link->pcp_a : link->pcp_b); + skb->dev = link->nic->dev; + skb_shinfo(skb)->tx_flags |= SKBTX_HW_TSTAMP; + skb->xmit_more = (more > 0 ? 1 : 0); + skb_set_mac_header(skb, 0); + + /* We are using a ethernet-type frame (even though we could send + * TSN over other medium. + * + * - skb_push(skb, ETH_HLEN) + * - set header htons(header) + * - set source addr (netdev mac addr) + * - set dest addr + * - return ETH_HLEN + */ + hard_hdr_len = dev_hard_header(skb, skb->dev, ETH_P_TSN, + link->remote_mac, NULL, 6); + + skb = vlan_insert_tag(skb, htons(ETH_P_8021Q), _get_8021q_vid(link)); + if (!skb) { + pr_err("%s: could not insert tag in buffer, aborting\n", + __func__); + return NULL; + } + + /* tsnh_assemble_du() will deref avtpdu to find start of data + * segment and use that, this is to update the skb + * appropriately. + * + * tsnh_assemble_du() will grab tsn-lock before updating link + */ + avtpdu = (struct avtpdu_header *)skb_put(skb, avtpdu_len); + res = tsnh_assemble_du(link, avtpdu, data_bytes, ts_pres_ns); + if (res < 0) { + pr_err("%s: Error initializing header (-> %d) , we are in an inconsistent state!\n", + __func__, res); + kfree_skb(skb); + return NULL; + } + + /* FIXME: Find a suitable Tx-queue + * + * For igb, this returns -1 + */ + queue_idx = sk_tx_queue_get(skb->sk); + if (queue_idx < 0 || queue_idx >= netdev->real_num_tx_queues) + queue_idx = 0; + skb_set_queue_mapping(skb, queue_idx); + skb->queue_mapping = 0; + + skb->csum = skb_checksum(skb, 0, hdr_len + data_bytes, 0); + return skb; +} + +/** + * Send a set of frames as efficiently as possible + */ +int tsn_net_send_set(struct tsn_link *link, size_t num, u64 ts_base_ns, + u64 ts_delta_ns) +{ + struct sk_buff *skb; + struct net_device *dev; + size_t data_size; + int res; + struct netdev_queue *txq; + u64 ts_pres_ns = ts_base_ns; + + if (!link) + return -EINVAL; + dev = link->nic->dev; + + /* create and init sk_buff_head */ + while (num-- > 0) { + data_size = tsn_shim_get_framesize(link); + + skb = _skbuf_create_init(link, data_size, + tsn_shim_get_hdr_size(link), + ts_pres_ns, (num > 0)); + if (!skb) { + pr_err("%s: could not allocate memory for skb\n", + __func__); + return -ENOMEM; + } + + trace_tsn_pre_tx(link, skb, data_size); + txq = skb_get_tx_queue(dev, skb); + if (!txq) { + pr_err("%s: Could not get tx_queue, dropping sending\n", + __func__); + kfree_skb(skb); + return -EINVAL; + } + res = netdev_start_xmit(skb, dev, txq, (num > 0)); + if (res != NETDEV_TX_OK) { + pr_err("%s: Tx FAILED\n", __func__); + return res; + } + ts_pres_ns += ts_delta_ns; + } + return 0; +}