diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /net/lapb/lapb_iface.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'net/lapb/lapb_iface.c')
| -rw-r--r-- | net/lapb/lapb_iface.c | 553 |
1 files changed, 553 insertions, 0 deletions
diff --git a/net/lapb/lapb_iface.c b/net/lapb/lapb_iface.c new file mode 100644 index 000000000..670e0859a --- /dev/null +++ b/net/lapb/lapb_iface.c @@ -0,0 +1,553 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LAPB release 002 + * + * This code REQUIRES 2.1.15 or higher/ NET3.038 + * + * History + * LAPB 001 Jonathan Naylor Started Coding + * LAPB 002 Jonathan Naylor New timer architecture. + * 2000-10-29 Henner Eisen lapb_data_indication() return status. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/inet.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/stat.h> +#include <linux/init.h> +#include <net/lapb.h> + +static LIST_HEAD(lapb_list); +static DEFINE_RWLOCK(lapb_list_lock); + +/* + * Free an allocated lapb control block. + */ +static void lapb_free_cb(struct lapb_cb *lapb) +{ + kfree(lapb); +} + +static __inline__ void lapb_hold(struct lapb_cb *lapb) +{ + refcount_inc(&lapb->refcnt); +} + +static __inline__ void lapb_put(struct lapb_cb *lapb) +{ + if (refcount_dec_and_test(&lapb->refcnt)) + lapb_free_cb(lapb); +} + +/* + * Socket removal during an interrupt is now safe. + */ +static void __lapb_remove_cb(struct lapb_cb *lapb) +{ + if (lapb->node.next) { + list_del(&lapb->node); + lapb_put(lapb); + } +} + +/* + * Add a socket to the bound sockets list. + */ +static void __lapb_insert_cb(struct lapb_cb *lapb) +{ + list_add(&lapb->node, &lapb_list); + lapb_hold(lapb); +} + +static struct lapb_cb *__lapb_devtostruct(struct net_device *dev) +{ + struct lapb_cb *lapb, *use = NULL; + + list_for_each_entry(lapb, &lapb_list, node) { + if (lapb->dev == dev) { + use = lapb; + break; + } + } + + if (use) + lapb_hold(use); + + return use; +} + +static struct lapb_cb *lapb_devtostruct(struct net_device *dev) +{ + struct lapb_cb *rc; + + read_lock_bh(&lapb_list_lock); + rc = __lapb_devtostruct(dev); + read_unlock_bh(&lapb_list_lock); + + return rc; +} +/* + * Create an empty LAPB control block. + */ +static struct lapb_cb *lapb_create_cb(void) +{ + struct lapb_cb *lapb = kzalloc_obj(*lapb, GFP_ATOMIC); + + if (!lapb) + goto out; + + skb_queue_head_init(&lapb->write_queue); + skb_queue_head_init(&lapb->ack_queue); + + timer_setup(&lapb->t1timer, NULL, 0); + timer_setup(&lapb->t2timer, NULL, 0); + lapb->t1timer_running = false; + lapb->t2timer_running = false; + + lapb->t1 = LAPB_DEFAULT_T1; + lapb->t2 = LAPB_DEFAULT_T2; + lapb->n2 = LAPB_DEFAULT_N2; + lapb->mode = LAPB_DEFAULT_MODE; + lapb->window = LAPB_DEFAULT_WINDOW; + lapb->state = LAPB_STATE_0; + + spin_lock_init(&lapb->lock); + refcount_set(&lapb->refcnt, 1); +out: + return lapb; +} + +int lapb_register(struct net_device *dev, + const struct lapb_register_struct *callbacks) +{ + struct lapb_cb *lapb; + int rc = LAPB_BADTOKEN; + + write_lock_bh(&lapb_list_lock); + + lapb = __lapb_devtostruct(dev); + if (lapb) { + lapb_put(lapb); + goto out; + } + + lapb = lapb_create_cb(); + rc = LAPB_NOMEM; + if (!lapb) + goto out; + + lapb->dev = dev; + lapb->callbacks = callbacks; + + __lapb_insert_cb(lapb); + + lapb_start_t1timer(lapb); + + rc = LAPB_OK; +out: + write_unlock_bh(&lapb_list_lock); + return rc; +} +EXPORT_SYMBOL(lapb_register); + +int lapb_unregister(struct net_device *dev) +{ + struct lapb_cb *lapb; + int rc = LAPB_BADTOKEN; + + write_lock_bh(&lapb_list_lock); + lapb = __lapb_devtostruct(dev); + if (!lapb) + goto out; + lapb_put(lapb); + + /* Wait for other refs to "lapb" to drop */ + while (refcount_read(&lapb->refcnt) > 2) + usleep_range(1, 10); + + spin_lock_bh(&lapb->lock); + + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + + lapb_clear_queues(lapb); + + spin_unlock_bh(&lapb->lock); + + /* Wait for running timers to stop */ + timer_delete_sync(&lapb->t1timer); + timer_delete_sync(&lapb->t2timer); + + __lapb_remove_cb(lapb); + + lapb_put(lapb); + rc = LAPB_OK; +out: + write_unlock_bh(&lapb_list_lock); + return rc; +} +EXPORT_SYMBOL(lapb_unregister); + +int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms) +{ + int rc = LAPB_BADTOKEN; + struct lapb_cb *lapb = lapb_devtostruct(dev); + + if (!lapb) + goto out; + + spin_lock_bh(&lapb->lock); + + parms->t1 = lapb->t1 / HZ; + parms->t2 = lapb->t2 / HZ; + parms->n2 = lapb->n2; + parms->n2count = lapb->n2count; + parms->state = lapb->state; + parms->window = lapb->window; + parms->mode = lapb->mode; + + if (!timer_pending(&lapb->t1timer)) + parms->t1timer = 0; + else + parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ; + + if (!timer_pending(&lapb->t2timer)) + parms->t2timer = 0; + else + parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ; + + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); + rc = LAPB_OK; +out: + return rc; +} +EXPORT_SYMBOL(lapb_getparms); + +int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms) +{ + int rc = LAPB_BADTOKEN; + struct lapb_cb *lapb = lapb_devtostruct(dev); + + if (!lapb) + goto out; + + spin_lock_bh(&lapb->lock); + + rc = LAPB_INVALUE; + if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1) + goto out_put; + + if (lapb->state == LAPB_STATE_0) { + if (parms->mode & LAPB_EXTENDED) { + if (parms->window < 1 || parms->window > 127) + goto out_put; + } else { + if (parms->window < 1 || parms->window > 7) + goto out_put; + } + lapb->mode = parms->mode; + lapb->window = parms->window; + } + + lapb->t1 = parms->t1 * HZ; + lapb->t2 = parms->t2 * HZ; + lapb->n2 = parms->n2; + + rc = LAPB_OK; +out_put: + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); +out: + return rc; +} +EXPORT_SYMBOL(lapb_setparms); + +int lapb_connect_request(struct net_device *dev) +{ + struct lapb_cb *lapb = lapb_devtostruct(dev); + int rc = LAPB_BADTOKEN; + + if (!lapb) + goto out; + + spin_lock_bh(&lapb->lock); + + rc = LAPB_OK; + if (lapb->state == LAPB_STATE_1) + goto out_put; + + rc = LAPB_CONNECTED; + if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4) + goto out_put; + + lapb_establish_data_link(lapb); + + lapb_dbg(0, "(%p) S0 -> S1\n", lapb->dev); + lapb->state = LAPB_STATE_1; + + rc = LAPB_OK; +out_put: + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); +out: + return rc; +} +EXPORT_SYMBOL(lapb_connect_request); + +static int __lapb_disconnect_request(struct lapb_cb *lapb) +{ + switch (lapb->state) { + case LAPB_STATE_0: + return LAPB_NOTCONNECTED; + + case LAPB_STATE_1: + lapb_dbg(1, "(%p) S1 TX DISC(1)\n", lapb->dev); + lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev); + lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); + lapb->state = LAPB_STATE_0; + lapb_start_t1timer(lapb); + return LAPB_NOTCONNECTED; + + case LAPB_STATE_2: + return LAPB_OK; + } + + lapb_clear_queues(lapb); + lapb->n2count = 0; + lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); + lapb_start_t1timer(lapb); + lapb_stop_t2timer(lapb); + lapb->state = LAPB_STATE_2; + + lapb_dbg(1, "(%p) S3 DISC(1)\n", lapb->dev); + lapb_dbg(0, "(%p) S3 -> S2\n", lapb->dev); + + return LAPB_OK; +} + +int lapb_disconnect_request(struct net_device *dev) +{ + struct lapb_cb *lapb = lapb_devtostruct(dev); + int rc = LAPB_BADTOKEN; + + if (!lapb) + goto out; + + spin_lock_bh(&lapb->lock); + + rc = __lapb_disconnect_request(lapb); + + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); +out: + return rc; +} +EXPORT_SYMBOL(lapb_disconnect_request); + +int lapb_data_request(struct net_device *dev, struct sk_buff *skb) +{ + struct lapb_cb *lapb = lapb_devtostruct(dev); + int rc = LAPB_BADTOKEN; + + if (!lapb) + goto out; + + spin_lock_bh(&lapb->lock); + + rc = LAPB_NOTCONNECTED; + if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4) + goto out_put; + + skb_queue_tail(&lapb->write_queue, skb); + lapb_kick(lapb); + rc = LAPB_OK; +out_put: + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); +out: + return rc; +} +EXPORT_SYMBOL(lapb_data_request); + +int lapb_data_received(struct net_device *dev, struct sk_buff *skb) +{ + struct lapb_cb *lapb = lapb_devtostruct(dev); + int rc = LAPB_BADTOKEN; + + if (lapb) { + spin_lock_bh(&lapb->lock); + lapb_data_input(lapb, skb); + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); + rc = LAPB_OK; + } + + return rc; +} +EXPORT_SYMBOL(lapb_data_received); + +void lapb_connect_confirmation(struct lapb_cb *lapb, int reason) +{ + if (lapb->callbacks->connect_confirmation) + lapb->callbacks->connect_confirmation(lapb->dev, reason); +} + +void lapb_connect_indication(struct lapb_cb *lapb, int reason) +{ + if (lapb->callbacks->connect_indication) + lapb->callbacks->connect_indication(lapb->dev, reason); +} + +void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason) +{ + if (lapb->callbacks->disconnect_confirmation) + lapb->callbacks->disconnect_confirmation(lapb->dev, reason); +} + +void lapb_disconnect_indication(struct lapb_cb *lapb, int reason) +{ + if (lapb->callbacks->disconnect_indication) + lapb->callbacks->disconnect_indication(lapb->dev, reason); +} + +int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb) +{ + if (lapb->callbacks->data_indication) + return lapb->callbacks->data_indication(lapb->dev, skb); + + kfree_skb(skb); + return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */ +} + +int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb) +{ + int used = 0; + + if (lapb->callbacks->data_transmit) { + lapb->callbacks->data_transmit(lapb->dev, skb); + used = 1; + } + + return used; +} + +/* Handle device status changes. */ +static int lapb_device_event(struct notifier_block *this, unsigned long event, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct lapb_cb *lapb; + + if (!net_eq(dev_net(dev), &init_net)) + return NOTIFY_DONE; + + if (dev->type != ARPHRD_X25) + return NOTIFY_DONE; + + lapb = lapb_devtostruct(dev); + if (!lapb) + return NOTIFY_DONE; + + spin_lock_bh(&lapb->lock); + + switch (event) { + case NETDEV_UP: + lapb_dbg(0, "(%p) Interface up: %s\n", dev, dev->name); + + if (netif_carrier_ok(dev)) { + lapb_dbg(0, "(%p): Carrier is already up: %s\n", dev, + dev->name); + if (lapb->mode & LAPB_DCE) { + lapb_start_t1timer(lapb); + } else { + if (lapb->state == LAPB_STATE_0) { + lapb->state = LAPB_STATE_1; + lapb_establish_data_link(lapb); + } + } + } + break; + case NETDEV_GOING_DOWN: + if (netif_carrier_ok(dev)) + __lapb_disconnect_request(lapb); + break; + case NETDEV_DOWN: + lapb_dbg(0, "(%p) Interface down: %s\n", dev, dev->name); + lapb_dbg(0, "(%p) S%d -> S0\n", dev, lapb->state); + lapb_clear_queues(lapb); + lapb->state = LAPB_STATE_0; + lapb->n2count = 0; + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + break; + case NETDEV_CHANGE: + if (netif_carrier_ok(dev)) { + lapb_dbg(0, "(%p): Carrier detected: %s\n", dev, + dev->name); + if (lapb->mode & LAPB_DCE) { + lapb_start_t1timer(lapb); + } else { + if (lapb->state == LAPB_STATE_0) { + lapb->state = LAPB_STATE_1; + lapb_establish_data_link(lapb); + } + } + } else { + lapb_dbg(0, "(%p) Carrier lost: %s\n", dev, dev->name); + lapb_dbg(0, "(%p) S%d -> S0\n", dev, lapb->state); + lapb_clear_queues(lapb); + lapb->state = LAPB_STATE_0; + lapb->n2count = 0; + lapb_stop_t1timer(lapb); + lapb_stop_t2timer(lapb); + } + break; + } + + spin_unlock_bh(&lapb->lock); + lapb_put(lapb); + return NOTIFY_DONE; +} + +static struct notifier_block lapb_dev_notifier = { + .notifier_call = lapb_device_event, +}; + +static int __init lapb_init(void) +{ + return register_netdevice_notifier(&lapb_dev_notifier); +} + +static void __exit lapb_exit(void) +{ + WARN_ON(!list_empty(&lapb_list)); + + unregister_netdevice_notifier(&lapb_dev_notifier); +} + +MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>"); +MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol"); +MODULE_LICENSE("GPL"); + +module_init(lapb_init); +module_exit(lapb_exit); |
