[PATCH] net: Linn Ethernet Packet Sniffer driver
From: Stathis Voukelatos
Date: Fri Jan 23 2015 - 05:07:41 EST
This patch adds support the Ethernet Packet Sniffer H/W module
developed by Linn Products Ltd and found in the IMG Pistachio SoC.
The module allows Ethernet packets to be parsed, matched against
a user-defined pattern and timestamped. It sits between a 100M
Ethernet MAC and PHY and is completely passive with respect to
Ethernet frames.
Matched packet bytes and timestamp values are returned through a
FIFO. Timestamps are provided to the module through an externally
generated Gray-encoded counter.
The command pattern for packet matching is stored in module RAM
and consists of a sequence of 16-bit entries. Each entry includes
an 8-bit command code and and 8-bit data value. Valid command
codes are:
0 - Don't care
1 - Match: packet data must match command string byte
2 - Copy: packet data will be copied to FIFO
3 - Match/Stamp: if packet data matches string byte, a timestamp
is copied into the FIFO
4 - Copy/Done: packet data will be copied into the FIFO.
This command terminates the command string.
The driver consists of two modules:
- Core: it provides an API to user space using the Generic Netlink
framework. Specific backend implementations, like the
Ethernet Packet Sniffer, register one or more channels
with the Core. For each channel a Genl family is created.
User space can access a channel by sending Genl messages
to the Genl family associated with the channel. Packet
matching events are multicast.
- Ethernet Packet Sniffer backend: provides the driver for the
Linn Ethernet Packet Sniffer H/W modules.
The split between a core and backend modules allows software-only
implementations to be added for platforms where no H/W support
is available.
Based on 3.19-rc5
Signed-off-by: Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
---
.../bindings/net/linn-ether-packet-sniffer.txt | 27 ++
.../devicetree/bindings/vendor-prefixes.txt | 1 +
MAINTAINERS | 7 +
drivers/net/Kconfig | 2 +
drivers/net/Makefile | 1 +
drivers/net/pkt-sniffer/Kconfig | 23 ++
drivers/net/pkt-sniffer/Makefile | 8 +
drivers/net/pkt-sniffer/backends/ether/channel.c | 366 ++++++++++++++++++
drivers/net/pkt-sniffer/backends/ether/channel.h | 76 ++++
drivers/net/pkt-sniffer/backends/ether/hw.h | 46 +++
drivers/net/pkt-sniffer/backends/ether/platform.c | 231 +++++++++++
drivers/net/pkt-sniffer/core/dev_table.c | 124 ++++++
drivers/net/pkt-sniffer/core/module.c | 37 ++
drivers/net/pkt-sniffer/core/nl.c | 427 +++++++++++++++++++++
drivers/net/pkt-sniffer/core/nl.h | 34 ++
drivers/net/pkt-sniffer/core/snf_core.h | 64 +++
include/linux/pkt_sniffer.h | 89 +++++
17 files changed, 1563 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/linn-ether-packet-sniffer.txt
create mode 100644 drivers/net/pkt-sniffer/Kconfig
create mode 100644 drivers/net/pkt-sniffer/Makefile
create mode 100644 drivers/net/pkt-sniffer/backends/ether/channel.c
create mode 100644 drivers/net/pkt-sniffer/backends/ether/channel.h
create mode 100644 drivers/net/pkt-sniffer/backends/ether/hw.h
create mode 100644 drivers/net/pkt-sniffer/backends/ether/platform.c
create mode 100644 drivers/net/pkt-sniffer/core/dev_table.c
create mode 100644 drivers/net/pkt-sniffer/core/module.c
create mode 100644 drivers/net/pkt-sniffer/core/nl.c
create mode 100644 drivers/net/pkt-sniffer/core/nl.h
create mode 100644 drivers/net/pkt-sniffer/core/snf_core.h
create mode 100644 include/linux/pkt_sniffer.h
diff --git a/Documentation/devicetree/bindings/net/linn-ether-packet-sniffer.txt b/Documentation/devicetree/bindings/net/linn-ether-packet-sniffer.txt
new file mode 100644
index 0000000..6b6e105
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/linn-ether-packet-sniffer.txt
@@ -0,0 +1,27 @@
+* Linn Products Ethernet Packet Sniffer
+
+Required properties:
+- compatible : must be "linn,eth-sniffer"
+- reg : physical addresses and sizes of registers. Must contain 3 entries:
+ first entry: registers memory space
+ second entry: TX command memory
+ third entry: RX command memory
+- reg-names : must contain the following 3 entries:
+ "regs", "tx-ram", "rx-ram"
+- interrupts : sniffer interrupt specifier
+- clocks : specify the system clock for the peripheral
+- clock-names : must contain the "sys" entry
+- fifo-block-words : number of words in one data FIFO entry
+
+Example:
+
+sniffer@1814a000 {
+ compatible = "linn,eth-sniffer";
+ reg = <0x1814a000 0x100>, <0x1814a400 0x400>, <0x1814a800 0x400>;
+ reg-names = "regs", "tx-ram", "rx-ram";
+ interrupts = <GIC_SHARED 58 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "eth-sniffer-irq";
+ clocks = <&system_clk>;
+ clock-names = "sys";
+ fifo-block-words = <4>;
+ };
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index b1df0ad..2c96f35 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -90,6 +90,7 @@ lacie LaCie
lantiq Lantiq Semiconductor
lenovo Lenovo Group Ltd.
lg LG Corporation
+linn Linn Products Ltd.
linux Linux-specific binding
lsi LSI Corp. (LSI Logic)
lltc Linear Technology Corporation
diff --git a/MAINTAINERS b/MAINTAINERS
index 2fa3853..7dbc6e7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5708,6 +5708,13 @@ M: Sasha Levin <sasha.levin@xxxxxxxxxx>
S: Maintained
F: tools/lib/lockdep/
+LINN PACKET SNIFFER DRIVER
+M: Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+S: Maintained
+F: include/linux/pkt_sniffer.h
+F: drivers/net/pkt-sniffer/
+F: Documentation/devicetree/bindings/net/linn-ether-packet-sniffer.txt
+
LINUX FOR IBM pSERIES (RS/6000)
M: Paul Mackerras <paulus@xxxxxxxxxx>
W: http://www.ibm.com/linux/ltc/projects/ppc
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index d6607ee..219c786 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -380,4 +380,6 @@ config VMXNET3
source "drivers/net/hyperv/Kconfig"
+source "drivers/net/pkt-sniffer/Kconfig"
+
endif # NETDEVICES
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index e25fdd7..441111b 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -66,3 +66,4 @@ obj-$(CONFIG_USB_NET_DRIVERS) += usb/
obj-$(CONFIG_HYPERV_NET) += hyperv/
obj-$(CONFIG_NTB_NETDEV) += ntb_netdev.o
+obj-$(CONFIG_PKT_SNIFFER) += pkt-sniffer/
diff --git a/drivers/net/pkt-sniffer/Kconfig b/drivers/net/pkt-sniffer/Kconfig
new file mode 100644
index 0000000..26b4f98
--- /dev/null
+++ b/drivers/net/pkt-sniffer/Kconfig
@@ -0,0 +1,23 @@
+menuconfig PKT_SNIFFER
+ tristate "Linn packet sniffer support"
+ ---help---
+ Say Y to add support for Linn packet sniffer drivers.
+
+ The core driver can also be built as a module. If so, the module
+ will be called snf_core.
+
+if PKT_SNIFFER
+
+config PKT_SNIFFER_ETHER
+ tristate "Ethernet packet sniffer"
+ depends on MIPS
+ default n
+ help
+ Say Y here if you want to use the Linn Ethernet packet sniffer
+ module. It can be found in the upcoming Pistachio SoC by
+ Imagination Technologies.
+
+ The driver can also be built as a module. If so, the module
+ will be called snf_ether.
+
+endif # PKT_SNIFFER
diff --git a/drivers/net/pkt-sniffer/Makefile b/drivers/net/pkt-sniffer/Makefile
new file mode 100644
index 0000000..07e7339
--- /dev/null
+++ b/drivers/net/pkt-sniffer/Makefile
@@ -0,0 +1,8 @@
+snf_core-y += core/nl.o
+snf_core-y += core/dev_table.o
+snf_core-y += core/module.o
+obj-$(CONFIG_PKT_SNIFFER) += snf_core.o
+
+snf_ether-y += backends/ether/platform.o
+snf_ether-y += backends/ether/channel.o
+obj-$(CONFIG_PKT_SNIFFER_ETHER) += snf_ether.o
diff --git a/drivers/net/pkt-sniffer/backends/ether/channel.c b/drivers/net/pkt-sniffer/backends/ether/channel.c
new file mode 100644
index 0000000..d483b58
--- /dev/null
+++ b/drivers/net/pkt-sniffer/backends/ether/channel.c
@@ -0,0 +1,366 @@
+/*
+ * Ethernet Mii packet sniffer driver
+ * - channel functions
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/pkt_sniffer.h>
+#include "../../core/snf_core.h"
+#include "hw.h"
+#include "channel.h"
+
+#define to_ether_snf_chan(dev) container_of(dev, struct ether_snf_chan, chan)
+
+static int esnf_start(struct snf_chan *dev);
+static int esnf_stop(struct snf_chan *dev);
+static int esnf_set_pattern(struct snf_chan *dev, const u8 *pattern, int count);
+static int esnf_num_recs_avail(struct snf_chan *dev);
+static int esnf_max_ptn_entries(struct snf_chan *dev);
+static int esnf_max_match_bytes(struct snf_chan *dev);
+static int validate_pattern(
+ struct ether_snf_chan *ch,
+ const u8 *buf,
+ int count);
+static void read_fifo_data(struct ether_snf_chan *ch);
+static u32 gray_decode(u32 gray);
+
+/* Initialises a sniffer channel */
+int channel_init(
+ struct ether_snf_chan *ch,
+ struct platform_device *pdev,
+ void *regs,
+ int fifo_blk_words,
+ int tx)
+{
+ struct resource *res;
+ u32 *ptr;
+ int i;
+
+ ch->regs = regs;
+ ch->dev = &pdev->dev;
+ ch->data_irq_bit = tx ? TX_DATA_IRQ_BIT : RX_DATA_IRQ_BIT;
+ ch->full_irq_bit = tx ? TX_FULL_IRQ_BIT : RX_FULL_IRQ_BIT;
+ ch->reg_enable = ch->regs +
+ (tx ? TX_SNIFFER_ENABLE : RX_SNIFFER_ENABLE);
+ ch->reg_occ = ch->regs + (tx ? TX_FIFO_OCC : RX_FIFO_OCC);
+ ch->reg_fifo = ch->regs + (tx ? TX_FIFO_DAT : RX_FIFO_DAT);
+
+ /* Retrieve and remap the address space for the command memory */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ tx ? "tx-ram" : "rx-ram");
+ if (!res)
+ return -ENOSYS;
+ ch->cmd_ram = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ch->cmd_ram))
+ return PTR_ERR(ch->cmd_ram);
+
+ /* It is 2 bytes/command, hence divide by 2 */
+ ch->max_cmds = resource_size(res) / 2;
+
+ /* Initialise the command pattern RAM */
+ for (i = 0, ptr = ch->cmd_ram; i < resource_size(res); i += 4)
+ iowrite32((PTN_CMD_DONTCARE << 24) | (PTN_CMD_DONTCARE << 8),
+ ptr++);
+
+ ch->fifo_blk_words = fifo_blk_words;
+ ch->started = 0;
+
+ /* Register the channel methods */
+ ch->chan.start = esnf_start;
+ ch->chan.stop = esnf_stop;
+ ch->chan.set_pattern = esnf_set_pattern;
+ ch->chan.num_recs_avail = esnf_num_recs_avail;
+ ch->chan.max_ptn_entries = esnf_max_ptn_entries;
+ ch->chan.max_match_bytes = esnf_max_match_bytes;
+
+ strncpy(ch->name, tx ? "TX" : "RX", MAX_CHAN_NAME_SIZE - 1);
+
+ dev_dbg(ch->dev, "%s channel initialized\n", ch->name);
+
+ return 0;
+}
+
+/* Registers the channel with the sniffer core module */
+int channel_register(struct ether_snf_chan *ch, const char *name)
+{
+ int id;
+
+ id = snf_channel_add(&ch->chan, name);
+ if (id < 0)
+ return id;
+
+ ch->id = id;
+ dev_info(ch->dev, "%s channel added\n", ch->name);
+ return 0;
+}
+
+/* Unregisters the channel */
+int channel_unregister(struct ether_snf_chan *ch)
+{
+ int ret;
+
+ ch->chan.stop(&ch->chan);
+ ret = snf_channel_remove(ch->id);
+ if (!ret)
+ dev_info(ch->dev, "%s channel removed\n", ch->name);
+ return ret;
+}
+
+/* Process match event data */
+void channel_data_available(struct ether_snf_chan *ch)
+{
+ int ret;
+
+ dev_dbg(ch->dev, "%s match event\n", ch->name);
+
+ read_fifo_data(ch);
+ ret = snf_channel_notify_match(&ch->chan, &ch->evt);
+ if (ret < 0)
+ dev_err(ch->dev, "%s: event notification failed\n", ch->name);
+}
+
+/* Channel methods */
+
+/* Enables the channel */
+static int esnf_start(struct snf_chan *dev)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+
+ if (!ch->started) {
+ /* Enable interrupts */
+ iowrite32(ch->data_irq_bit | ch->full_irq_bit,
+ ch->regs + SET_INTERRUPT_ENABLE);
+ /* Enable the packet matching logic */
+ iowrite32(ENABLE_BIT, ch->reg_enable);
+
+ ch->started = 1;
+ dev_info(ch->dev, "%s channel started\n", ch->name);
+ } else {
+ dev_dbg(ch->dev, "%s channel already running\n", ch->name);
+ }
+
+ return 0;
+}
+
+/* Disables the channel */
+static int esnf_stop(struct snf_chan *dev)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+
+ if (ch->started) {
+ /* Disable interrupts */
+ iowrite32(ch->data_irq_bit | ch->full_irq_bit,
+ ch->regs + CLEAR_INTERRUPT_ENABLE);
+ /* Stop the sniffer channel */
+ iowrite32(0, ch->reg_enable);
+ /* Clear any pending interrupts */
+ iowrite32(ch->data_irq_bit | ch->full_irq_bit,
+ ch->regs + INTERRUPT_STATUS);
+
+ ch->started = 0;
+ dev_info(ch->dev, "%s channel stopped\n", ch->name);
+ } else {
+ dev_dbg(ch->dev, "%s channel already stopped\n", ch->name);
+ }
+
+ return 0;
+}
+
+/* Sets the command string (pattern) for the channel
+ * The bytes in the pattern buffer are in the following order:
+ */
+static int esnf_set_pattern(struct snf_chan *dev, const u8 *pattern, int count)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+ int i, shift = 0;
+ u32 val = 0, *ptr;
+
+ if (ch->started) {
+ dev_err(ch->dev,
+ "cannot apply cmd pattern. %s channel is active\n",
+ ch->name);
+ return -EBUSY;
+ }
+
+ if (!validate_pattern(ch, pattern, count)) {
+ dev_err(ch->dev,
+ "invalid cmd pattern for %s channel\n",
+ ch->name);
+ return -EINVAL;
+ }
+
+ for (ptr = ch->cmd_ram, i = 0, shift = 24; i < (2*count); i++) {
+ val |= ((u32)pattern[i]) << shift;
+ if (!shift) {
+ iowrite32(val, ptr++);
+ val = 0;
+ shift = 24;
+ } else {
+ shift -= 8;
+ }
+ }
+ if (shift)
+ iowrite32(val, ptr);
+
+ return 0;
+}
+
+/* Returns the number of pending match events that are
+ * available to retrieve
+ */
+static int esnf_num_recs_avail(struct snf_chan *dev)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+
+ return ioread32(ch->reg_occ);
+}
+
+/* Returns max number of commands supported by the channel */
+static int esnf_max_ptn_entries(struct snf_chan *dev)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+
+ return ch->max_cmds;
+}
+
+/* Returns max number of bytes that can be returned by a match */
+static int esnf_max_match_bytes(struct snf_chan *dev)
+{
+ struct ether_snf_chan *ch = to_ether_snf_chan(dev);
+
+ /* Subtract the word that may be used for the timestamp */
+ return (ch->fifo_blk_words - 1) * 4;
+}
+
+/* Checks if the supplied command string is compatible with the
+ * capabilities of the H/W
+ */
+static int validate_pattern(struct ether_snf_chan *ch, const u8 *buf, int count)
+{
+ int i, complete, max_copy_bytes;
+ int ts = 0;
+ int copy_before = 0;
+ int copy_after = 0;
+
+ if (count > ch->max_cmds)
+ return 0;
+
+ /* Iterate through the commands in the string */
+ for (i = 0, complete = 0; (i < count) && !complete; i++) {
+ u8 cmd = buf[2*i];
+
+ switch (cmd) {
+ case PTN_CMD_DONTCARE:
+ case PTN_CMD_MATCH:
+ break;
+
+ case PTN_CMD_MATCHSTAMP:
+ /* The timestamp needs to be word-aligned in the FIFO
+ * therefore, the number of 'copy' commands before it
+ * needs to be a multiple of 4
+ */
+ if (copy_before & 3)
+ return 0;
+ /* Signal that a timestamp will be present */
+ ts = 1;
+ break;
+
+ case PTN_CMD_COPY:
+ /* Increment count of bytes that will be returned */
+ if (ts)
+ copy_after++;
+ else
+ copy_before++;
+ break;
+
+ case PTN_CMD_COPYDONE:
+ /* Increment count of bytes that will be returned
+ * This command terminates the string
+ */
+ if (ts)
+ copy_after++;
+ else
+ copy_before++;
+ complete = 1;
+ break;
+
+ default:
+ return 0;
+ }
+ }
+
+ /* Check if the string was properly terminated
+ * and contained valid number of commands
+ */
+ if (complete) {
+ max_copy_bytes = ch->fifo_blk_words * 4;
+ if (ts)
+ max_copy_bytes -= 4;
+ if ((copy_before + copy_after) > max_copy_bytes)
+ return 0;
+ ch->ts_present = ts;
+ ch->nfb_before = copy_before;
+ ch->nfb_after = copy_after;
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+/* Read a block from the data FIFO */
+static void read_fifo_data(struct ether_snf_chan *ch)
+{
+ int i;
+ u32 val, *ptr;
+ int ts = ch->ts_present;
+ int dw = ch->fifo_blk_words;
+ int bytes_before = ch->nfb_before;
+ int bytes_after = ch->nfb_after;
+
+ ptr = (u32 *)ch->evt.data;
+ for (i = 0; i < dw; i++) {
+ val = ioread32(ch->reg_fifo);
+ if (bytes_before > 0) {
+ /* Bytes before the timestamp */
+ *ptr++ = cpu_to_be32(val);
+ bytes_before -= 4;
+ } else if (ts) {
+ /* Timestamp is Gray encoded */
+ ch->evt.ts = (u64)gray_decode(val);
+ ts = 0;
+ } else if (bytes_after > 0) {
+ /* Bytes after the timestamp */
+ *ptr++ = cpu_to_be32(val);
+ bytes_after -= 4;
+ }
+ }
+
+ ch->evt.ts_valid = ch->ts_present;
+ ch->evt.len = ch->nfb_before + ch->nfb_after;
+}
+
+/* Gray decoder */
+static u32 gray_decode(u32 gray)
+{
+ gray ^= (gray >> 16);
+ gray ^= (gray >> 8);
+ gray ^= (gray >> 4);
+ gray ^= (gray >> 2);
+ gray ^= (gray >> 1);
+ return gray;
+}
+
diff --git a/drivers/net/pkt-sniffer/backends/ether/channel.h b/drivers/net/pkt-sniffer/backends/ether/channel.h
new file mode 100644
index 0000000..4f00b33
--- /dev/null
+++ b/drivers/net/pkt-sniffer/backends/ether/channel.h
@@ -0,0 +1,76 @@
+/*
+ * Ethernet Mii packet sniffer driver
+ * - channel interface
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#ifndef _ETHER_SNIFFER_CHANNEL_H_
+#define _ETHER_SNIFFER_CHANNEL_H_
+
+#include <linux/platform_device.h>
+#include "../../core/snf_core.h"
+
+#define MAX_CHAN_NAME_SIZE 5
+
+struct ether_snf_chan {
+ /* Sniffer core structure */
+ struct snf_chan chan;
+ /* Pointer to device struct */
+ struct device *dev;
+ /* Registers */
+ u8 __iomem *regs;
+ /* Command string memory */
+ u32 __iomem *cmd_ram;
+ /* Bit number for the data IRQ */
+ int data_irq_bit;
+ /* Bit number for the FIFO full IRQ */
+ int full_irq_bit;
+ /* Channel enable register */
+ u8 __iomem *reg_enable;
+ /* Data FIFO register */
+ u8 __iomem *reg_fifo;
+ /* FIFO occupancy register */
+ u8 __iomem *reg_occ;
+ /* Max number of commands in the string */
+ int max_cmds;
+ /* Max matching bytes that can fit in a FIFO block */
+ int fifo_blk_words;
+ /* Number of bytes in the FIFO before the timestamp */
+ int nfb_before;
+ /* Number of bytes in the FIFO after the timestamp */
+ int nfb_after;
+ /* Timestamp present flag */
+ int ts_present;
+ /* ID assigned to channel by the sniffer core */
+ int id;
+ /* Channel active flag */
+ int started;
+ /* Channel name (only used by debug messages) */
+ char name[MAX_CHAN_NAME_SIZE];
+ /* Struct to hold data from a packet match */
+ struct snf_match_evt evt;
+};
+
+int channel_init(
+ struct ether_snf_chan *ch,
+ struct platform_device *pdev,
+ void *regs,
+ int fifo_blk_words,
+ int tx);
+int channel_register(struct ether_snf_chan *ch, const char *name);
+int channel_unregister(struct ether_snf_chan *ch);
+void channel_data_available(struct ether_snf_chan *ch);
+
+#endif
diff --git a/drivers/net/pkt-sniffer/backends/ether/hw.h b/drivers/net/pkt-sniffer/backends/ether/hw.h
new file mode 100644
index 0000000..edb1093
--- /dev/null
+++ b/drivers/net/pkt-sniffer/backends/ether/hw.h
@@ -0,0 +1,46 @@
+/*
+ * Ethernet Mii packet sniffer driver
+ * - register map
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#ifndef _ETHER_SNIFFER_HW_H_
+#define _ETHER_SNIFFER_HW_H_
+
+#include <linux/bitops.h>
+
+/* Registers */
+#define INTERRUPT_ENABLE 0x00
+#define SET_INTERRUPT_ENABLE 0x04
+#define CLEAR_INTERRUPT_ENABLE 0x08
+#define INTERRUPT_STATUS 0x0c
+#define TX_FIFO_DAT 0x10
+#define RX_FIFO_DAT 0x14
+#define TX_FIFO_OCC 0x18
+#define RX_FIFO_OCC 0x1c
+#define TX_SNIFFER_ENABLE 0x20
+#define RX_SNIFFER_ENABLE 0x24
+
+/* IRQ register bits */
+#define TX_DATA_IRQ_BIT BIT(0)
+#define RX_DATA_IRQ_BIT BIT(1)
+#define TX_FULL_IRQ_BIT BIT(2)
+#define RX_FULL_IRQ_BIT BIT(3)
+
+/* Enable register bits */
+#define ENABLE_BIT BIT(0)
+
+#endif
+
diff --git a/drivers/net/pkt-sniffer/backends/ether/platform.c b/drivers/net/pkt-sniffer/backends/ether/platform.c
new file mode 100644
index 0000000..78e7e1c
--- /dev/null
+++ b/drivers/net/pkt-sniffer/backends/ether/platform.c
@@ -0,0 +1,231 @@
+/*
+ * Ethernet Mii packet sniffer driver
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include "../../core/snf_core.h"
+#include "hw.h"
+#include "channel.h"
+
+static const char esnf_driver_name[] = "eth-sniffer";
+
+/* Names for the TX and RX channel.
+ * User space will used these names to access the channels
+ * through the generic netlink interface
+ */
+static const char tx_channel_name[] = "snf_ether_tx";
+static const char rx_channel_name[] = "snf_ether_rx";
+
+struct ether_snf {
+ u8 __iomem *regs;
+ int irq;
+ struct clk *sys_clk;
+ struct ether_snf_chan txc;
+ struct ether_snf_chan rxc;
+};
+
+/* Interrupt thread function */
+static irqreturn_t esnf_irq_thread(int irq, void *dev_id)
+{
+ struct platform_device *pdev = (struct platform_device *)dev_id;
+ struct ether_snf *esnf = (struct ether_snf *)platform_get_drvdata(pdev);
+ u32 irq_status;
+
+ if (unlikely(esnf->irq != irq))
+ return IRQ_NONE;
+
+ irq_status = ioread32(esnf->regs + INTERRUPT_STATUS) &
+ ioread32(esnf->regs + INTERRUPT_ENABLE);
+
+ dev_dbg(&pdev->dev, "irq: 0x%08x\n", irq_status);
+
+ /* TX FIFO full */
+ if (unlikely(irq_status & TX_FULL_IRQ_BIT))
+ dev_notice(&pdev->dev, "TX FIFO full");
+
+ /* RX FIFO full */
+ if (unlikely(irq_status & RX_FULL_IRQ_BIT))
+ dev_notice(&pdev->dev, "RX FIFO full");
+
+ /* TX match data available */
+ if (irq_status & TX_DATA_IRQ_BIT) {
+ dev_dbg(&pdev->dev, "TX data");
+ channel_data_available(&esnf->txc);
+ }
+
+ /* RX match data available */
+ if (irq_status & RX_DATA_IRQ_BIT) {
+ dev_dbg(&pdev->dev, "RX data");
+ channel_data_available(&esnf->rxc);
+ }
+
+ /* Clear interrupts */
+ iowrite32(irq_status, esnf->regs + INTERRUPT_STATUS);
+
+ return IRQ_HANDLED;
+}
+
+/* Called when the packet sniffer device is bound with the driver */
+static int esnf_driver_probe(struct platform_device *pdev)
+{
+ struct ether_snf *esnf;
+ struct resource *res;
+ int ret, irq;
+ u32 fifo_blk_words;
+ void __iomem *regs;
+ struct device_node *ofn = pdev->dev.of_node;
+
+ /* Allocate the device data structure */
+ esnf = devm_kzalloc(&pdev->dev, sizeof(*esnf), GFP_KERNEL);
+ if (!esnf)
+ return -ENOMEM;
+
+ /* Retrieve and remap register memory space */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
+ if (!res)
+ return -ENODEV;
+
+ regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ esnf->regs = regs;
+
+ /* Read the FIFO block size from the DT */
+ if (!ofn)
+ return -ENODEV;
+
+ ret = of_property_read_u32(
+ ofn,
+ "fifo-block-words",
+ &fifo_blk_words);
+ if (ret < 0)
+ return ret;
+
+ if (((fifo_blk_words - 1)*4) > MAX_MATCH_BYTES) {
+ dev_err(&pdev->dev,
+ "Invalid FIFO block size entry in device tree\n");
+ return -EINVAL;
+ }
+
+ esnf->sys_clk = devm_clk_get(&pdev->dev, "sys");
+ if (IS_ERR(esnf->sys_clk)) {
+ ret = PTR_ERR(esnf->sys_clk);
+ return ret;
+ }
+ ret = clk_prepare_enable(esnf->sys_clk);
+ if (ret < 0)
+ return ret;
+
+ /* Initialise the TX and RX channels */
+ ret = channel_init(&esnf->txc, pdev, regs, fifo_blk_words, 1);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to init TX channel (%d)\n", ret);
+ goto fail1;
+ }
+ ret = channel_init(&esnf->rxc, pdev, regs, fifo_blk_words, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to init RX channel (%d)\n", ret);
+ goto fail1;
+ }
+
+ /* Register the channels with the sniffer core module */
+ ret = channel_register(&esnf->txc, tx_channel_name);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register TX chan (%d)\n", ret);
+ goto fail1;
+ }
+ ret = channel_register(&esnf->rxc, rx_channel_name);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register RX chan (%d)\n", ret);
+ goto fail2;
+ }
+
+ platform_set_drvdata(pdev, esnf);
+
+ /* Register the interrupt handler */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ goto fail3;
+ esnf->irq = irq;
+ ret = devm_request_threaded_irq(
+ &pdev->dev,
+ irq,
+ NULL,
+ esnf_irq_thread,
+ IRQF_ONESHOT,
+ esnf_driver_name,
+ pdev);
+ if (ret < 0)
+ goto fail3;
+
+ return 0;
+
+fail3:
+ channel_unregister(&esnf->rxc);
+fail2:
+ channel_unregister(&esnf->txc);
+fail1:
+ clk_disable_unprepare(esnf->sys_clk);
+ return ret;
+}
+
+/* Called when the packet sniffer device unregisters with the driver */
+static int esnf_driver_remove(struct platform_device *pdev)
+{
+ struct ether_snf *esnf = (struct ether_snf *)platform_get_drvdata(pdev);
+ int ret;
+
+ ret = channel_unregister(&esnf->txc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to unregister TX chan (%d)\n", ret);
+ return ret;
+ }
+ ret = channel_unregister(&esnf->rxc);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to unregister RX chan (%d)\n", ret);
+ return ret;
+ }
+ clk_disable_unprepare(esnf->sys_clk);
+ return 0;
+}
+
+static const struct of_device_id esnf_of_match_table[] = {
+ { .compatible = "linn,eth-sniffer", .data = NULL },
+ {},
+};
+MODULE_DEVICE_TABLE(of, esnf_of_match_table);
+
+static struct platform_driver esnf_platform_driver = {
+ .driver = {
+ .name = esnf_driver_name,
+ .of_match_table = esnf_of_match_table,
+ },
+ .probe = esnf_driver_probe,
+ .remove = esnf_driver_remove,
+};
+
+module_platform_driver(esnf_platform_driver);
+
+MODULE_DESCRIPTION("Linn Ethernet Packet Sniffer");
+MODULE_AUTHOR("Linn Products Ltd");
+MODULE_LICENSE("GPL v2");
+
diff --git a/drivers/net/pkt-sniffer/core/dev_table.c b/drivers/net/pkt-sniffer/core/dev_table.c
new file mode 100644
index 0000000..3a07838
--- /dev/null
+++ b/drivers/net/pkt-sniffer/core/dev_table.c
@@ -0,0 +1,124 @@
+/*
+ * Packet sniffer core driver: channel management
+ *
+ * Copyright (C) 2014 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include "snf_core.h"
+#include "nl.h"
+
+#define MAX_CHANNELS 256
+
+static DEFINE_MUTEX(tlock);
+
+static struct snf_chan *dev_tab[MAX_CHANNELS];
+static unsigned int ref_count[MAX_CHANNELS];
+
+static inline int verify_args(int id)
+{
+ return (id < MAX_CHANNELS);
+}
+
+/* Registers a sniffer channel and returns and id for it */
+int snf_channel_add(struct snf_chan *dev, const char *name)
+{
+ int i;
+ int ret = -EEXIST;
+
+ mutex_lock(&tlock);
+
+ for (i = 0; i < MAX_CHANNELS; i++) {
+ if (!dev_tab[i]) {
+ /* Initialise the netlink interface for the channel */
+ ret = snf_netlink_init(i, dev, name);
+ if (ret < 0)
+ goto fail;
+
+ dev_tab[i] = dev;
+ ref_count[i] = 0;
+ mutex_unlock(&tlock);
+ return i;
+ }
+ }
+
+fail:
+ mutex_unlock(&tlock);
+ return ret;
+}
+EXPORT_SYMBOL(snf_channel_add);
+
+/* Removes a sniffer channel */
+int snf_channel_remove(int id)
+{
+ int ret = 0;
+ struct snf_chan *dev;
+
+ if (!verify_args(id))
+ return -EINVAL;
+
+ mutex_lock(&tlock);
+
+ dev = dev_tab[id];
+
+ if (!dev) {
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ if (ref_count[id] > 0) {
+ ret = -EBUSY;
+ goto fail;
+ }
+
+ dev_tab[id] = NULL;
+
+ /* Release netlink API resources */
+ snf_netlink_release(dev);
+
+fail:
+ mutex_unlock(&tlock);
+ return ret;
+}
+EXPORT_SYMBOL(snf_channel_remove);
+
+/* Returns a pointer to the specified sniffer channel
+ * and increments its reference counter
+ */
+struct snf_chan *snf_channel_get(int id)
+{
+ struct snf_chan *dev;
+
+ if (!verify_args(id))
+ return NULL;
+
+ mutex_lock(&tlock);
+ dev = dev_tab[id];
+ if (dev)
+ ref_count[id]++;
+ mutex_unlock(&tlock);
+
+ return dev;
+}
+
+/* Decrements the reference counter for the channel */
+void snf_channel_put(int id)
+{
+ mutex_lock(&tlock);
+ if (ref_count[id] > 0)
+ ref_count[id]--;
+ mutex_unlock(&tlock);
+}
+
diff --git a/drivers/net/pkt-sniffer/core/module.c b/drivers/net/pkt-sniffer/core/module.c
new file mode 100644
index 0000000..af6a1aa
--- /dev/null
+++ b/drivers/net/pkt-sniffer/core/module.c
@@ -0,0 +1,37 @@
+/*
+ * Packet sniffer core driver:
+ * - backend channel management
+ * - interface to userland via generic netlink
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+
+static int __init snf_core_init(void)
+{
+ return 0;
+}
+
+static void __exit snf_core_cleanup(void)
+{
+}
+
+module_init(snf_core_init);
+module_exit(snf_core_cleanup);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Core packet sniffer driver");
+MODULE_AUTHOR("Linn Products Ltd");
diff --git a/drivers/net/pkt-sniffer/core/nl.c b/drivers/net/pkt-sniffer/core/nl.c
new file mode 100644
index 0000000..6839147
--- /dev/null
+++ b/drivers/net/pkt-sniffer/core/nl.c
@@ -0,0 +1,427 @@
+/*
+ * Packet sniffer core driver: generic netlink interface
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#include <linux/version.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/pkt_sniffer.h>
+#include "snf_core.h"
+#include "nl.h"
+
+/* Netlink API data for a sniffer channel */
+struct snf_netlink {
+ /* genl family */
+ struct genl_family fml;
+ /* genl operations */
+ struct genl_ops *ops;
+ /* genl mcast group, where sniffer match
+ * events will be sent
+ */
+ struct genl_multicast_group grp;
+};
+
+/* Attribute policies */
+static struct nla_policy snf_policy[SNF_ATTR_MAX + 1] = {
+ [SNF_ATTR_PATTERN] = { .type = NLA_NESTED },
+};
+
+static struct nla_policy snf_ptn_policy[SNF_ATTR_PTN_MAX + 1] = {
+ [SNF_ATTR_PTN_ENTRY] = { .type = NLA_U16 },
+};
+
+/* Generic Netlink family template definition */
+static int pre_doit_func(const struct genl_ops *ops,
+ struct sk_buff *skb,
+ struct genl_info *info);
+
+static void post_doit_func(const struct genl_ops *ops,
+ struct sk_buff *skb,
+ struct genl_info *info);
+
+static struct genl_family snf_family_tmpl = {
+ .id = GENL_ID_GENERATE,
+ .hdrsize = 0,
+ .version = SNF_GNL_VERSION,
+ .maxattr = SNF_ATTR_MAX,
+ .pre_doit = pre_doit_func,
+ .post_doit = post_doit_func
+};
+
+static int send_reply_uint32(
+ struct genl_info *info,
+ int cmd,
+ int attr,
+ u32 val);
+
+/* Generic Netlink operations template definition */
+
+static int do_it_start(struct sk_buff *skb, struct genl_info *info);
+static int do_it_stop(struct sk_buff *skb, struct genl_info *info);
+static int do_it_set_pattern(struct sk_buff *skb, struct genl_info *info);
+static int do_it_num_rec_avail(struct sk_buff *skb, struct genl_info *info);
+static int do_it_ptn_max_cmds(struct sk_buff *skb, struct genl_info *info);
+static int do_it_max_match_bytes(struct sk_buff *skb, struct genl_info *info);
+
+#define SNF_GENL_OP(_cmd, _func) \
+ { \
+ .cmd = _cmd, \
+ .policy = snf_policy, \
+ .doit = _func, \
+ .dumpit = NULL, \
+ .flags = 0, \
+ .internal_flags = 0 \
+ }
+
+#define SNF_CHAN_OPS \
+ { \
+ SNF_GENL_OP(SNF_CMD_START, do_it_start), \
+ SNF_GENL_OP(SNF_CMD_STOP, do_it_stop), \
+ SNF_GENL_OP(SNF_CMD_SETPATTERN, do_it_set_pattern), \
+ SNF_GENL_OP(SNF_CMD_NUMRECAVAIL, do_it_num_rec_avail), \
+ SNF_GENL_OP(SNF_CMD_PTNMAXCMDS, do_it_ptn_max_cmds), \
+ SNF_GENL_OP(SNF_CMD_MAXMATCHBYTES, do_it_max_match_bytes) \
+ }
+
+static struct genl_ops snf_ops_tmpl[] = SNF_CHAN_OPS;
+
+#define NUM_GENL_OPS ARRAY_SIZE(snf_ops_tmpl)
+
+/* Multicast a netlink event containing data from a sniffer match event.
+ * Data are included in the netlink message as a nested attribute
+ * containing the timestamp (optional) and matching packet bytes
+*/
+int snf_channel_notify_match(struct snf_chan *dev, struct snf_match_evt *mt)
+{
+ int i, ret = 0;
+ struct sk_buff *msg = NULL;
+ void *msg_hdr, *nest_hdr;
+ struct snf_netlink *nl = (struct snf_netlink *)dev->cstate;
+
+ if (!nl) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ msg = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+ if (!msg) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ msg_hdr = genlmsg_put(msg,
+ 0,
+ 0,
+ &nl->fml,
+ 0,
+ SNF_CMD_MATCHEVENT);
+ if (!msg_hdr) {
+ ret = -EMSGSIZE;
+ goto fail;
+ }
+
+ /* Add the nested attribute with the data */
+ if ((mt->ts_valid) || (mt->len > 0)) {
+ nest_hdr = nla_nest_start(msg, SNF_ATTR_MATCHEVENT);
+ if (!nest_hdr) {
+ ret = -EMSGSIZE;
+ goto fail;
+ }
+ if (mt->ts_valid) {
+ ret = nla_put_u64(msg, SNF_ATTR_MATCH_TS, mt->ts);
+ if (ret < 0)
+ goto fail;
+ }
+ for (i = 0; i < mt->len; i++) {
+ ret = nla_put_u8(msg,
+ SNF_ATTR_MATCH_PKTBYTE,
+ mt->data[i]);
+ if (ret < 0)
+ goto fail;
+ }
+ nla_nest_end(msg, nest_hdr);
+ }
+
+ ret = genlmsg_end(msg, msg_hdr);
+ if (ret < 0)
+ goto fail;
+ ret = genlmsg_multicast(&nl->fml, msg, 0, 0, GFP_ATOMIC);
+
+ /* The ESRCH code is returned when there is no socket listening on the
+ * multicast group, so we do not really treat is as an error
+ */
+ if (ret == -ESRCH)
+ ret = 0;
+ return ret;
+
+fail:
+ if (msg)
+ nlmsg_free(msg);
+ return ret;
+}
+EXPORT_SYMBOL(snf_channel_notify_match);
+
+/* Initialise the generic netlink API for a sniffer channel
+ * Registers family, ops and multicast group for events
+ */
+int snf_netlink_init(int id, struct snf_chan *dev, const char *name)
+{
+ int i, ret;
+ struct snf_netlink *nl = NULL;
+
+ nl = kmalloc(sizeof(*nl), GFP_KERNEL);
+ if (!nl) {
+ ret = -ENOMEM;
+ goto fail1;
+ }
+
+ nl->fml = snf_family_tmpl;
+
+ /* Set the family name */
+ strncpy(nl->fml.name, name, GENL_NAMSIZ-1);
+
+ /* Allocate ops array and copy template data */
+ nl->ops = kmalloc(sizeof(snf_ops_tmpl), GFP_KERNEL);
+ if (!nl->ops) {
+ ret = -ENOMEM;
+ goto fail2;
+ }
+ memcpy(nl->ops, snf_ops_tmpl, sizeof(snf_ops_tmpl));
+
+ /* In the internal_flags field we store the id
+ * of the device the ops belong to
+ */
+ for (i = 0; i < NUM_GENL_OPS; i++)
+ nl->ops[i].internal_flags = id;
+
+ snprintf(nl->grp.name, GENL_NAMSIZ-1, SNF_EVENT_GRP);
+
+ ret = _genl_register_family_with_ops_grps(
+ &nl->fml,
+ nl->ops,
+ NUM_GENL_OPS,
+ &nl->grp,
+ 1);
+ if (ret < 0) {
+ pr_err("%s: failed to register family %s (%d)\n",
+ KBUILD_MODNAME, name, ret);
+ goto fail3;
+ }
+
+ pr_info("%s: registered genl family for channel %d: %s\n",
+ KBUILD_MODNAME, id, name);
+ dev->cstate = nl;
+
+ return 0;
+
+fail3:
+ kfree(nl->ops);
+fail2:
+ kfree(nl);
+fail1:
+ return ret;
+}
+
+/* Shuts down the netlink API for a sniffer channel
+ * and frees resources
+ */
+void snf_netlink_release(struct snf_chan *dev)
+{
+ struct snf_netlink *nl = (struct snf_netlink *)dev->cstate;
+ /* Unregister family and free ops
+ * NOTE: this will also unregister the ops and the mcast group
+ */
+ genl_unregister_family(&nl->fml);
+ pr_info("%s: unregistered genl family: %s\n",
+ KBUILD_MODNAME, nl->fml.name);
+
+ kfree(nl->ops);
+ kfree(nl);
+ dev->cstate = NULL;
+}
+
+/* pre_doit function that retrieves a pointer to the sniffer channel device
+ * from the instance and channel number stored in the ops internal_flag field
+ */
+static int pre_doit_func(const struct genl_ops *ops,
+ struct sk_buff *skb,
+ struct genl_info *info)
+{
+ info->user_ptr[0] = snf_channel_get(ops->internal_flags);
+ return info->user_ptr[0] ? 0 : -ENODEV;
+}
+
+/* post_doit function that releases a sniffer channel device */
+static void post_doit_func(const struct genl_ops *ops,
+ struct sk_buff *skb,
+ struct genl_info *info)
+{
+ snf_channel_put(ops->internal_flags);
+}
+
+/* doit command handlers */
+
+/* Start the sniffer channel */
+static int do_it_start(struct sk_buff *skb, struct genl_info *info)
+{
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+
+ return dev->start(dev);
+}
+
+/* Stop the sniffer channel */
+static int do_it_stop(struct sk_buff *skb, struct genl_info *info)
+{
+ int ret;
+ struct snf_match_evt mt;
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+
+ ret = dev->stop(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Multicast an empty match event to notify any user-space
+ * listeners that the sniffer is stopping
+ */
+ memset(&mt, 0, sizeof(mt));
+ return snf_channel_notify_match(dev, &mt);
+}
+
+/* Set the command pattern. The string is received in a nested
+ * attribute containing a sequence of 16-bit valued.
+ * Each value consists of a command (8 bits) and data (8 bits)
+*/
+static int do_it_set_pattern(struct sk_buff *skb, struct genl_info *info)
+{
+ int ret = 0;
+ int rem, count;
+ struct nlattr *nla;
+ u16 entry;
+ u8 *buf = NULL;
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+ int max_entries = dev->max_ptn_entries(dev);
+
+ if (!info->attrs[SNF_ATTR_PATTERN]) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ ret = nla_validate_nested(info->attrs[SNF_ATTR_PATTERN],
+ SNF_ATTR_PTN_ENTRY, snf_ptn_policy);
+ if (ret < 0)
+ goto fail;
+
+ buf = kmalloc(max_entries*2, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ /* Iterate over the contents of the nested attribute
+ * and extract into the buffer
+ */
+ count = 0;
+ nla_for_each_nested(nla, info->attrs[SNF_ATTR_PATTERN], rem) {
+ if (count >= max_entries) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ entry = nla_get_u16(nla);
+ buf[2*count] = PTNENTRY_CMD(entry);
+ buf[2*count + 1] = PTNENTRY_DATA(entry);
+ count++;
+ }
+
+ ret = dev->set_pattern(dev, buf, count);
+
+fail:
+ kfree(buf);
+ return ret;
+}
+
+/* Number of pending match events */
+static int do_it_num_rec_avail(struct sk_buff *skb, struct genl_info *info)
+{
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+
+ return send_reply_uint32(
+ info,
+ SNF_CMD_NUMRECAVAIL,
+ SNF_ATTR_NUMRECAVAIL,
+ dev->num_recs_avail(dev));
+}
+
+/* Max number of commands that are supported in the command pattern */
+static int do_it_ptn_max_cmds(struct sk_buff *skb, struct genl_info *info)
+{
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+
+ return send_reply_uint32(
+ info,
+ SNF_CMD_PTNMAXCMDS,
+ SNF_ATTR_PTNMAXCMDS,
+ dev->max_ptn_entries(dev));
+}
+
+/* Max bytes that can be returned by a packet match event */
+static int do_it_max_match_bytes(struct sk_buff *skb, struct genl_info *info)
+{
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+
+ return send_reply_uint32(
+ info,
+ SNF_CMD_MAXMATCHBYTES,
+ SNF_ATTR_MAXMATCHBYTES,
+ dev->max_match_bytes(dev));
+}
+
+/* Helper function for sending a reply containing a single u32 attribute */
+static int send_reply_uint32(struct genl_info *info, int cmd, int attr, u32 val)
+{
+ void *hdr;
+ int ret = 0;
+ struct sk_buff *msg;
+ struct snf_chan *dev = (struct snf_chan *)info->user_ptr[0];
+ struct snf_netlink *nl = (struct snf_netlink *)dev->cstate;
+
+ msg = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+ if (!msg) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ hdr = genlmsg_put_reply(msg, info, &nl->fml, 0, cmd);
+ if (!hdr) {
+ ret = -EMSGSIZE;
+ goto fail;
+ }
+ ret = nla_put_u32(msg, attr, val);
+ if (ret < 0)
+ goto fail;
+ ret = genlmsg_end(msg, hdr);
+ if (ret < 0)
+ goto fail;
+
+ return genlmsg_reply(msg, info);
+
+fail:
+ if (msg)
+ nlmsg_free(msg);
+ return ret;
+}
+
diff --git a/drivers/net/pkt-sniffer/core/nl.h b/drivers/net/pkt-sniffer/core/nl.h
new file mode 100644
index 0000000..f7bf579
--- /dev/null
+++ b/drivers/net/pkt-sniffer/core/nl.h
@@ -0,0 +1,34 @@
+/*
+ * Packet sniffer core driver: generic netlink interface
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#ifndef __SNF_NL_H
+#define __SNF_NL_H
+
+#include <net/genetlink.h>
+#include "snf_core.h"
+
+/* Initialise netlink interface for a sniffer channel,
+ * register netlink families etc.
+ */
+int snf_netlink_init(int id, struct snf_chan *dev, const char *name);
+
+/* Shutdown netlink interface, unregister
+ * families etc.
+ */
+void snf_netlink_release(struct snf_chan *dev);
+
+#endif
diff --git a/drivers/net/pkt-sniffer/core/snf_core.h b/drivers/net/pkt-sniffer/core/snf_core.h
new file mode 100644
index 0000000..062de70
--- /dev/null
+++ b/drivers/net/pkt-sniffer/core/snf_core.h
@@ -0,0 +1,64 @@
+/*
+ * Packet sniffer core driver
+ * - this header provides the interface to specific backend packet
+ * sniffer implementations
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#ifndef __SNF_CORE_H
+#define __SNF_CORE_H
+
+#include <linux/types.h>
+
+/* This is a global maximum. Each backend will have its own limit */
+#define MAX_MATCH_BYTES 512
+
+/* Sniffer channel data structure */
+struct snf_chan {
+ int (*start)(struct snf_chan *dev);
+ int (*stop)(struct snf_chan *dev);
+ int (*set_pattern)(struct snf_chan *dev, const u8 *pattern, int count);
+ int (*num_recs_avail)(struct snf_chan *dev);
+ int (*max_ptn_entries)(struct snf_chan *dev);
+ int (*max_match_bytes)(struct snf_chan *dev);
+
+ void *cstate;
+};
+
+/* Data from a sniffer match event */
+struct snf_match_evt {
+ int ts_valid; /* flag indicating if timestamp is present */
+ u64 ts; /* timestamp value */
+ u8 data[MAX_MATCH_BYTES]; /* packet data bytes matched by sniffer */
+ int len; /* number of valid bytes in the 'data' buffer */
+};
+
+/* Adds a sniffer channel to the registry */
+int snf_channel_add(struct snf_chan *dev, const char *name);
+
+/* Removes the channel with the specified id from the registry */
+int snf_channel_remove(int id);
+
+/* Returns handle to a channel and increments reference count */
+struct snf_chan *snf_channel_get(int id);
+
+/* Decrements reference count for the specified channel */
+void snf_channel_put(int id);
+
+/* Multicast a notification to user space for a sniffer match event */
+int snf_channel_notify_match(struct snf_chan *dev, struct snf_match_evt *mt);
+
+#endif
+
diff --git a/include/linux/pkt_sniffer.h b/include/linux/pkt_sniffer.h
new file mode 100644
index 0000000..3e73d14
--- /dev/null
+++ b/include/linux/pkt_sniffer.h
@@ -0,0 +1,89 @@
+/*
+ * Linn packet sniffer driver interface
+ *
+ * Copyright (C) 2015 Linn Products Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Written by:
+ * Stathis Voukelatos <stathis.voukelatos@xxxxxxxxxx>
+ */
+#ifndef __PKT_SNIFFER_H
+#define __PKT_SNIFFER_H
+
+/* Commands for the pattern string */
+#define PTN_CMD_DONTCARE 0
+#define PTN_CMD_MATCH 1
+#define PTN_CMD_COPY 2
+#define PTN_CMD_MATCHSTAMP 3
+#define PTN_CMD_COPYDONE 4
+
+/* Creates an entry for the pattern string.
+ * An entry consists of a command byte and a data byte
+*/
+#define MAKE_PTN_ENTRY(cmd, data) (((((int)cmd) & 0xff) << 8) | (data & 0xff))
+/* Gets the cmd and data portion of a pattern string entry */
+#define PTNENTRY_CMD(val) (((val) >> 8) & 0xff)
+#define PTNENTRY_DATA(val) ((val) & 0xff)
+
+/* Generic Netlink commands */
+enum {
+ SNF_CMD_UNSPEC,
+ SNF_CMD_START, /* start the sniffer */
+ SNF_CMD_STOP, /* stop the sniffer */
+ SNF_CMD_SETPATTERN, /* set the command pattern */
+ SNF_CMD_NUMRECAVAIL, /* number of pending match events */
+ SNF_CMD_MATCHEVENT, /* match event notification */
+ SNF_CMD_PTNMAXCMDS, /* max number of commands supported */
+ SNF_CMD_MAXMATCHBYTES, /* max number of bytes in match event */
+ __SNF_CMD_MAX
+};
+#define SNF_CMD_MAX (__SNF_CMD_MAX - 1)
+
+/* Generic Netlink attributes */
+enum {
+ SNF_ATTR_UNSPEC,
+ SNF_ATTR_PTNMAXCMDS, /* max number of commands supported */
+ SNF_ATTR_PATTERN, /* nested attribute containing commands */
+ SNF_ATTR_NUMRECAVAIL, /* number of pending match events */
+ SNF_ATTR_MATCHEVENT, /* nested attribute for a match event */
+ SNF_ATTR_MAXMATCHBYTES, /* max bytes in a match event */
+ __SNF_ATTR_MAX
+};
+#define SNF_ATTR_MAX (__SNF_ATTR_MAX - 1)
+
+/* Attributes that are included in the nested attribute
+ * for the command string
+ */
+enum {
+ SNF_ATTR_PTN_UNSPEC,
+ SNF_ATTR_PTN_ENTRY, /* command entry containing a command id */
+ __SNF_ATTR_PTN_MAX /* and data byte */
+};
+#define SNF_ATTR_PTN_MAX (__SNF_ATTR_PTN_MAX - 1)
+
+/* Attributes included in the nested attribute
+ * of a match event notification
+ */
+enum {
+ SNF_ATTR_MATCH_UNSPEC,
+ SNF_ATTR_MATCH_TS, /* timestamp (returned with a match event) */
+ SNF_ATTR_MATCH_PKTBYTE, /* packet data (returned with a match event) */
+ __SNF_ATTR_MATCH_MAX
+};
+#define SNF_ATTR_MATCH_MAX (__SNF_ATTR_MATCH_MAX - 1)
+
+/* Family version */
+#define SNF_GNL_VERSION 1
+
+/* Multicast group name */
+#define SNF_EVENT_GRP "snf_evt_grp"
+
+#endif
--
1.9.1
--
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