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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/char/misc.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to '')
-rw-r--r--drivers/char/misc.c308
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
new file mode 100644
index 000000000..7a1388b05
--- /dev/null
+++ b/drivers/char/misc.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/drivers/char/misc.c
+ *
+ * Generic misc open routine by Johan Myreen
+ *
+ * Based on code from Linus
+ *
+ * Teemu Rantanen's Microsoft Busmouse support and Derrick Cole's
+ * changes incorporated into 0.97pl4
+ * by Peter Cervasio (pete%q106fm.uucp@wupost.wustl.edu) (08SEP92)
+ * See busmouse.c for particulars.
+ *
+ * Made things a lot mode modular - easy to compile in just one or two
+ * of the misc drivers, as they are now completely independent. Linus.
+ *
+ * Support for loadable modules. 8-Sep-95 Philip Blundell <pjb27@cam.ac.uk>
+ *
+ * Fixed a failing symbol register to free the device registration
+ * Alan Cox <alan@lxorguk.ukuu.org.uk> 21-Jan-96
+ *
+ * Dynamic minors and /proc/mice by Alessandro Rubini. 26-Mar-96
+ *
+ * Renamed to misc and miscdevice to be more accurate. Alan Cox 26-Mar-96
+ *
+ * Handling of mouse minor numbers for kerneld:
+ * Idea by Jacques Gelinas <jack@solucorp.qc.ca>,
+ * adapted by Bjorn Ekwall <bj0rn@blox.se>
+ * corrected by Alan Cox <alan@lxorguk.ukuu.org.uk>
+ *
+ * Changes for kmod (from kerneld):
+ * Cyrus Durgin <cider@speakeasy.org>
+ *
+ * Added devfs support. Richard Gooch <rgooch@atnf.csiro.au> 10-Jan-1998
+ */
+
+#include <linux/module.h>
+
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/mutex.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/kmod.h>
+#include <linux/gfp.h>
+
+/*
+ * Head entry for the doubly linked miscdevice list
+ */
+static LIST_HEAD(misc_list);
+static DEFINE_MUTEX(misc_mtx);
+
+/*
+ * Assigned numbers, used for dynamic minors
+ */
+#define DYNAMIC_MINORS 128 /* like dynamic majors */
+static DEFINE_IDA(misc_minors_ida);
+
+static int misc_minor_alloc(void)
+{
+ int ret;
+
+ ret = ida_alloc_max(&misc_minors_ida, DYNAMIC_MINORS - 1, GFP_KERNEL);
+ if (ret >= 0) {
+ ret = DYNAMIC_MINORS - ret - 1;
+ } else {
+ ret = ida_alloc_range(&misc_minors_ida, MISC_DYNAMIC_MINOR + 1,
+ MINORMASK, GFP_KERNEL);
+ }
+ return ret;
+}
+
+static void misc_minor_free(int minor)
+{
+ if (minor < DYNAMIC_MINORS)
+ ida_free(&misc_minors_ida, DYNAMIC_MINORS - minor - 1);
+ else if (minor > MISC_DYNAMIC_MINOR)
+ ida_free(&misc_minors_ida, minor);
+}
+
+#ifdef CONFIG_PROC_FS
+static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ mutex_lock(&misc_mtx);
+ return seq_list_start(&misc_list, *pos);
+}
+
+static void *misc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &misc_list, pos);
+}
+
+static void misc_seq_stop(struct seq_file *seq, void *v)
+{
+ mutex_unlock(&misc_mtx);
+}
+
+static int misc_seq_show(struct seq_file *seq, void *v)
+{
+ const struct miscdevice *p = list_entry(v, struct miscdevice, list);
+
+ seq_printf(seq, "%3i %s\n", p->minor, p->name ? p->name : "");
+ return 0;
+}
+
+
+static const struct seq_operations misc_seq_ops = {
+ .start = misc_seq_start,
+ .next = misc_seq_next,
+ .stop = misc_seq_stop,
+ .show = misc_seq_show,
+};
+#endif
+
+static int misc_open(struct inode *inode, struct file *file)
+{
+ int minor = iminor(inode);
+ struct miscdevice *c = NULL, *iter;
+ int err = -ENODEV;
+ const struct file_operations *new_fops = NULL;
+
+ mutex_lock(&misc_mtx);
+
+ list_for_each_entry(iter, &misc_list, list) {
+ if (iter->minor != minor)
+ continue;
+ c = iter;
+ new_fops = fops_get(iter->fops);
+ break;
+ }
+
+ if (!new_fops) {
+ mutex_unlock(&misc_mtx);
+ request_module("char-major-%d-%d", MISC_MAJOR, minor);
+ mutex_lock(&misc_mtx);
+
+ list_for_each_entry(iter, &misc_list, list) {
+ if (iter->minor != minor)
+ continue;
+ c = iter;
+ new_fops = fops_get(iter->fops);
+ break;
+ }
+ if (!new_fops)
+ goto fail;
+ }
+
+ /*
+ * Place the miscdevice in the file's
+ * private_data so it can be used by the
+ * file operations, including f_op->open below
+ */
+ file->private_data = c;
+
+ err = 0;
+ replace_fops(file, new_fops);
+ if (file->f_op->open)
+ err = file->f_op->open(inode, file);
+fail:
+ mutex_unlock(&misc_mtx);
+ return err;
+}
+
+static struct class *misc_class;
+
+static const struct file_operations misc_fops = {
+ .owner = THIS_MODULE,
+ .open = misc_open,
+ .llseek = noop_llseek,
+};
+
+/**
+ * misc_register - register a miscellaneous device
+ * @misc: device structure
+ *
+ * Register a miscellaneous device with the kernel. If the minor
+ * number is set to %MISC_DYNAMIC_MINOR a minor number is assigned
+ * and placed in the minor field of the structure. For other cases
+ * the minor number requested is used.
+ *
+ * The structure passed is linked into the kernel and may not be
+ * destroyed until it has been unregistered. By default, an open()
+ * syscall to the device sets file->private_data to point to the
+ * structure. Drivers don't need open in fops for this.
+ *
+ * A zero is returned on success and a negative errno code for
+ * failure.
+ */
+
+int misc_register(struct miscdevice *misc)
+{
+ dev_t dev;
+ int err = 0;
+ bool is_dynamic = (misc->minor == MISC_DYNAMIC_MINOR);
+
+ INIT_LIST_HEAD(&misc->list);
+
+ mutex_lock(&misc_mtx);
+
+ if (is_dynamic) {
+ int i = misc_minor_alloc();
+
+ if (i < 0) {
+ err = -EBUSY;
+ goto out;
+ }
+ misc->minor = i;
+ } else {
+ struct miscdevice *c;
+
+ list_for_each_entry(c, &misc_list, list) {
+ if (c->minor == misc->minor) {
+ err = -EBUSY;
+ goto out;
+ }
+ }
+ }
+
+ dev = MKDEV(MISC_MAJOR, misc->minor);
+
+ misc->this_device =
+ device_create_with_groups(misc_class, misc->parent, dev,
+ misc, misc->groups, "%s", misc->name);
+ if (IS_ERR(misc->this_device)) {
+ if (is_dynamic) {
+ misc_minor_free(misc->minor);
+ misc->minor = MISC_DYNAMIC_MINOR;
+ }
+ err = PTR_ERR(misc->this_device);
+ goto out;
+ }
+
+ /*
+ * Add it to the front, so that later devices can "override"
+ * earlier defaults
+ */
+ list_add(&misc->list, &misc_list);
+ out:
+ mutex_unlock(&misc_mtx);
+ return err;
+}
+EXPORT_SYMBOL(misc_register);
+
+/**
+ * misc_deregister - unregister a miscellaneous device
+ * @misc: device to unregister
+ *
+ * Unregister a miscellaneous device that was previously
+ * successfully registered with misc_register().
+ */
+
+void misc_deregister(struct miscdevice *misc)
+{
+ if (WARN_ON(list_empty(&misc->list)))
+ return;
+
+ mutex_lock(&misc_mtx);
+ list_del(&misc->list);
+ device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
+ misc_minor_free(misc->minor);
+ mutex_unlock(&misc_mtx);
+}
+EXPORT_SYMBOL(misc_deregister);
+
+static char *misc_devnode(const struct device *dev, umode_t *mode)
+{
+ const struct miscdevice *c = dev_get_drvdata(dev);
+
+ if (mode && c->mode)
+ *mode = c->mode;
+ if (c->nodename)
+ return kstrdup(c->nodename, GFP_KERNEL);
+ return NULL;
+}
+
+static int __init misc_init(void)
+{
+ int err;
+ struct proc_dir_entry *ret;
+
+ ret = proc_create_seq("misc", 0, NULL, &misc_seq_ops);
+ misc_class = class_create(THIS_MODULE, "misc");
+ err = PTR_ERR(misc_class);
+ if (IS_ERR(misc_class))
+ goto fail_remove;
+
+ err = -EIO;
+ if (register_chrdev(MISC_MAJOR, "misc", &misc_fops))
+ goto fail_printk;
+ misc_class->devnode = misc_devnode;
+ return 0;
+
+fail_printk:
+ pr_err("unable to get major %d for misc devices\n", MISC_MAJOR);
+ class_destroy(misc_class);
+fail_remove:
+ if (ret)
+ remove_proc_entry("misc", NULL);
+ return err;
+}
+subsys_initcall(misc_init);