1 files changed, 533 insertions, 0 deletions

diff --git a/net/can/proc.c b/net/can/proc.c
new file mode 100644
index 000000000000..520fef5e5398
--- /dev/null
+++ b/net/can/proc.c
@@ -0,0 +1,533 @@
+/*
+ * proc.c - procfs support for Protocol family CAN core module
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <linux/can/core.h>
+
+#include "af_can.h"
+
+/*
+ * proc filenames for the PF_CAN core
+ */
+
+#define CAN_PROC_VERSION     "version"
+#define CAN_PROC_STATS       "stats"
+#define CAN_PROC_RESET_STATS "reset_stats"
+#define CAN_PROC_RCVLIST_ALL "rcvlist_all"
+#define CAN_PROC_RCVLIST_FIL "rcvlist_fil"
+#define CAN_PROC_RCVLIST_INV "rcvlist_inv"
+#define CAN_PROC_RCVLIST_SFF "rcvlist_sff"
+#define CAN_PROC_RCVLIST_EFF "rcvlist_eff"
+#define CAN_PROC_RCVLIST_ERR "rcvlist_err"
+
+static struct proc_dir_entry *can_dir;
+static struct proc_dir_entry *pde_version;
+static struct proc_dir_entry *pde_stats;
+static struct proc_dir_entry *pde_reset_stats;
+static struct proc_dir_entry *pde_rcvlist_all;
+static struct proc_dir_entry *pde_rcvlist_fil;
+static struct proc_dir_entry *pde_rcvlist_inv;
+static struct proc_dir_entry *pde_rcvlist_sff;
+static struct proc_dir_entry *pde_rcvlist_eff;
+static struct proc_dir_entry *pde_rcvlist_err;
+
+static int user_reset;
+
+static const char rx_list_name[][8] = {
+        [RX_ERR] = "rx_err",
+        [RX_ALL] = "rx_all",
+        [RX_FIL] = "rx_fil",
+        [RX_INV] = "rx_inv",
+        [RX_EFF] = "rx_eff",
+};
+
+/*
+ * af_can statistics stuff
+ */
+
+static void can_init_stats(void)
+{
+        /*
+         * This memset function is called from a timer context (when
+         * can_stattimer is active which is the default) OR in a process
+         * context (reading the proc_fs when can_stattimer is disabled).
+         */
+        memset(&can_stats, 0, sizeof(can_stats));
+        can_stats.jiffies_init = jiffies;
+
+        can_pstats.stats_reset++;
+
+        if (user_reset) {
+                user_reset = 0;
+                can_pstats.user_reset++;
+        }
+}
+
+static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
+                               unsigned long count)
+{
+        unsigned long rate;
+
+        if (oldjif == newjif)
+                return 0;
+
+        /* see can_stat_update() - this should NEVER happen! */
+        if (count > (ULONG_MAX / HZ)) {
+                printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n",
+                       count);
+                return 99999999;
+        }
+
+        rate = (count * HZ) / (newjif - oldjif);
+
+        return rate;
+}
+
+void can_stat_update(unsigned long data)
+{
+        unsigned long j = jiffies; /* snapshot */
+
+        /* restart counting in timer context on user request */
+        if (user_reset)
+                can_init_stats();
+
+        /* restart counting on jiffies overflow */
+        if (j < can_stats.jiffies_init)
+                can_init_stats();
+
+        /* prevent overflow in calc_rate() */
+        if (can_stats.rx_frames > (ULONG_MAX / HZ))
+                can_init_stats();
+
+        /* prevent overflow in calc_rate() */
+        if (can_stats.tx_frames > (ULONG_MAX / HZ))
+                can_init_stats();
+
+        /* matches overflow - very improbable */
+        if (can_stats.matches > (ULONG_MAX / 100))
+                can_init_stats();
+
+        /* calc total values */
+        if (can_stats.rx_frames)
+                can_stats.total_rx_match_ratio = (can_stats.matches * 100) /
+                        can_stats.rx_frames;
+
+        can_stats.total_tx_rate = calc_rate(can_stats.jiffies_init, j,
+                                            can_stats.tx_frames);
+        can_stats.total_rx_rate = calc_rate(can_stats.jiffies_init, j,
+                                            can_stats.rx_frames);
+
+        /* calc current values */
+        if (can_stats.rx_frames_delta)
+                can_stats.current_rx_match_ratio =
+                        (can_stats.matches_delta * 100) /
+                        can_stats.rx_frames_delta;
+
+        can_stats.current_tx_rate = calc_rate(0, HZ, can_stats.tx_frames_delta);
+        can_stats.current_rx_rate = calc_rate(0, HZ, can_stats.rx_frames_delta);
+
+        /* check / update maximum values */
+        if (can_stats.max_tx_rate < can_stats.current_tx_rate)
+                can_stats.max_tx_rate = can_stats.current_tx_rate;
+
+        if (can_stats.max_rx_rate < can_stats.current_rx_rate)
+                can_stats.max_rx_rate = can_stats.current_rx_rate;
+
+        if (can_stats.max_rx_match_ratio < can_stats.current_rx_match_ratio)
+                can_stats.max_rx_match_ratio = can_stats.current_rx_match_ratio;
+
+        /* clear values for 'current rate' calculation */
+        can_stats.tx_frames_delta = 0;
+        can_stats.rx_frames_delta = 0;
+        can_stats.matches_delta   = 0;
+
+        /* restart timer (one second) */
+        mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
+}
+
+/*
+ * proc read functions
+ *
+ * From known use-cases we expect about 10 entries in a receive list to be
+ * printed in the proc_fs. So PAGE_SIZE is definitely enough space here.
+ *
+ */
+
+static int can_print_rcvlist(char *page, int len, struct hlist_head *rx_list,
+                             struct net_device *dev)
+{
+        struct receiver *r;
+        struct hlist_node *n;
+
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(r, n, rx_list, list) {
+                char *fmt = (r->can_id & CAN_EFF_FLAG)?
+                        "   %-5s  %08X  %08x  %08x  %08x  %8ld  %s\n" :
+                        "   %-5s     %03X    %08x  %08lx  %08lx  %8ld  %s\n";
+
+                len += snprintf(page + len, PAGE_SIZE - len, fmt,
+                                DNAME(dev), r->can_id, r->mask,
+                                (unsigned long)r->func, (unsigned long)r->data,
+                                r->matches, r->ident);
+
+                /* does a typical line fit into the current buffer? */
+
+                /* 100 Bytes before end of buffer */
+                if (len > PAGE_SIZE - 100) {
+                        /* mark output cut off */
+                        len += snprintf(page + len, PAGE_SIZE - len,
+                                        "   (..)\n");
+                        break;
+                }
+        }
+        rcu_read_unlock();
+
+        return len;
+}
+
+static int can_print_recv_banner(char *page, int len)
+{
+        /*
+         *                  can1.  00000000  00000000  00000000
+         *                 .......          0  tp20
+         */
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        "  device   can_id   can_mask  function"
+                        "  userdata   matches  ident\n");
+
+        return len;
+}
+
+static int can_proc_read_stats(char *page, char **start, off_t off,
+                               int count, int *eof, void *data)
+{
+        int len = 0;
+
+        len += snprintf(page + len, PAGE_SIZE - len, "\n");
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        " %8ld transmitted frames (TXF)\n",
+                        can_stats.tx_frames);
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        " %8ld received frames (RXF)\n", can_stats.rx_frames);
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        " %8ld matched frames (RXMF)\n", can_stats.matches);
+
+        len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+        if (can_stattimer.function == can_stat_update) {
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld %% total match ratio (RXMR)\n",
+                                can_stats.total_rx_match_ratio);
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s total tx rate (TXR)\n",
+                                can_stats.total_tx_rate);
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s total rx rate (RXR)\n",
+                                can_stats.total_rx_rate);
+
+                len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld %% current match ratio (CRXMR)\n",
+                                can_stats.current_rx_match_ratio);
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s current tx rate (CTXR)\n",
+                                can_stats.current_tx_rate);
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s current rx rate (CRXR)\n",
+                                can_stats.current_rx_rate);
+
+                len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld %% max match ratio (MRXMR)\n",
+                                can_stats.max_rx_match_ratio);
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s max tx rate (MTXR)\n",
+                                can_stats.max_tx_rate);
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld frames/s max rx rate (MRXR)\n",
+                                can_stats.max_rx_rate);
+
+                len += snprintf(page + len, PAGE_SIZE - len, "\n");
+        }
+
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        " %8ld current receive list entries (CRCV)\n",
+                        can_pstats.rcv_entries);
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        " %8ld maximum receive list entries (MRCV)\n",
+                        can_pstats.rcv_entries_max);
+
+        if (can_pstats.stats_reset)
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                "\n %8ld statistic resets (STR)\n",
+                                can_pstats.stats_reset);
+
+        if (can_pstats.user_reset)
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                " %8ld user statistic resets (USTR)\n",
+                                can_pstats.user_reset);
+
+        len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+        *eof = 1;
+        return len;
+}
+
+static int can_proc_read_reset_stats(char *page, char **start, off_t off,
+                                     int count, int *eof, void *data)
+{
+        int len = 0;
+
+        user_reset = 1;
+
+        if (can_stattimer.function == can_stat_update) {
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                "Scheduled statistic reset #%ld.\n",
+                                can_pstats.stats_reset + 1);
+
+        } else {
+                if (can_stats.jiffies_init != jiffies)
+                        can_init_stats();
+
+                len += snprintf(page + len, PAGE_SIZE - len,
+                                "Performed statistic reset #%ld.\n",
+                                can_pstats.stats_reset);
+        }
+
+        *eof = 1;
+        return len;
+}
+
+static int can_proc_read_version(char *page, char **start, off_t off,
+                                 int count, int *eof, void *data)
+{
+        int len = 0;
+
+        len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
+                        CAN_VERSION_STRING);
+        *eof = 1;
+        return len;
+}
+
+static int can_proc_read_rcvlist(char *page, char **start, off_t off,
+                                 int count, int *eof, void *data)
+{
+        /* double cast to prevent GCC warning */
+        int idx = (int)(long)data;
+        int len = 0;
+        struct dev_rcv_lists *d;
+        struct hlist_node *n;
+
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        "\nreceive list '%s':\n", rx_list_name[idx]);
+
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
+
+                if (!hlist_empty(&d->rx[idx])) {
+                        len = can_print_recv_banner(page, len);
+                        len = can_print_rcvlist(page, len, &d->rx[idx], d->dev);
+                } else
+                        len += snprintf(page + len, PAGE_SIZE - len,
+                                        "  (%s: no entry)\n", DNAME(d->dev));
+
+                /* exit on end of buffer? */
+                if (len > PAGE_SIZE - 100)
+                        break;
+        }
+        rcu_read_unlock();
+
+        len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+        *eof = 1;
+        return len;
+}
+
+static int can_proc_read_rcvlist_sff(char *page, char **start, off_t off,
+                                     int count, int *eof, void *data)
+{
+        int len = 0;
+        struct dev_rcv_lists *d;
+        struct hlist_node *n;
+
+        /* RX_SFF */
+        len += snprintf(page + len, PAGE_SIZE - len,
+                        "\nreceive list 'rx_sff':\n");
+
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
+                int i, all_empty = 1;
+                /* check wether at least one list is non-empty */
+                for (i = 0; i < 0x800; i++)
+                        if (!hlist_empty(&d->rx_sff[i])) {
+                                all_empty = 0;
+                                break;
+                        }
+
+                if (!all_empty) {
+                        len = can_print_recv_banner(page, len);
+                        for (i = 0; i < 0x800; i++) {
+                                if (!hlist_empty(&d->rx_sff[i]) &&
+                                    len < PAGE_SIZE - 100)
+                                        len = can_print_rcvlist(page, len,
+                                                                &d->rx_sff[i],
+                                                                d->dev);
+                        }
+                } else
+                        len += snprintf(page + len, PAGE_SIZE - len,
+                                        "  (%s: no entry)\n", DNAME(d->dev));
+
+                /* exit on end of buffer? */
+                if (len > PAGE_SIZE - 100)
+                        break;
+        }
+        rcu_read_unlock();
+
+        len += snprintf(page + len, PAGE_SIZE - len, "\n");
+
+        *eof = 1;
+        return len;
+}
+
+/*
+ * proc utility functions
+ */
+
+static struct proc_dir_entry *can_create_proc_readentry(const char *name,
+                                                        mode_t mode,
+                                                        read_proc_t *read_proc,
+                                                        void *data)
+{
+        if (can_dir)
+                return create_proc_read_entry(name, mode, can_dir, read_proc,
+                                              data);
+        else
+                return NULL;
+}
+
+static void can_remove_proc_readentry(const char *name)
+{
+        if (can_dir)
+                remove_proc_entry(name, can_dir);
+}
+
+/*
+ * can_init_proc - create main CAN proc directory and procfs entries
+ */
+void can_init_proc(void)
+{
+        /* create /proc/net/can directory */
+        can_dir = proc_mkdir("can", init_net.proc_net);
+
+        if (!can_dir) {
+                printk(KERN_INFO "can: failed to create /proc/net/can . "
+                       "CONFIG_PROC_FS missing?\n");
+                return;
+        }
+
+        can_dir->owner = THIS_MODULE;
+
+        /* own procfs entries from the AF_CAN core */
+        pde_version     = can_create_proc_readentry(CAN_PROC_VERSION, 0644,
+                                        can_proc_read_version, NULL);
+        pde_stats       = can_create_proc_readentry(CAN_PROC_STATS, 0644,
+                                        can_proc_read_stats, NULL);
+        pde_reset_stats = can_create_proc_readentry(CAN_PROC_RESET_STATS, 0644,
+                                        can_proc_read_reset_stats, NULL);
+        pde_rcvlist_err = can_create_proc_readentry(CAN_PROC_RCVLIST_ERR, 0644,
+                                        can_proc_read_rcvlist, (void *)RX_ERR);
+        pde_rcvlist_all = can_create_proc_readentry(CAN_PROC_RCVLIST_ALL, 0644,
+                                        can_proc_read_rcvlist, (void *)RX_ALL);
+        pde_rcvlist_fil = can_create_proc_readentry(CAN_PROC_RCVLIST_FIL, 0644,
+                                        can_proc_read_rcvlist, (void *)RX_FIL);
+        pde_rcvlist_inv = can_create_proc_readentry(CAN_PROC_RCVLIST_INV, 0644,
+                                        can_proc_read_rcvlist, (void *)RX_INV);
+        pde_rcvlist_eff = can_create_proc_readentry(CAN_PROC_RCVLIST_EFF, 0644,
+                                        can_proc_read_rcvlist, (void *)RX_EFF);
+        pde_rcvlist_sff = can_create_proc_readentry(CAN_PROC_RCVLIST_SFF, 0644,
+                                        can_proc_read_rcvlist_sff, NULL);
+}
+
+/*
+ * can_remove_proc - remove procfs entries and main CAN proc directory
+ */
+void can_remove_proc(void)
+{
+        if (pde_version)
+                can_remove_proc_readentry(CAN_PROC_VERSION);
+
+        if (pde_stats)
+                can_remove_proc_readentry(CAN_PROC_STATS);
+
+        if (pde_reset_stats)
+                can_remove_proc_readentry(CAN_PROC_RESET_STATS);
+
+        if (pde_rcvlist_err)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_ERR);
+
+        if (pde_rcvlist_all)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_ALL);
+
+        if (pde_rcvlist_fil)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_FIL);
+
+        if (pde_rcvlist_inv)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_INV);
+
+        if (pde_rcvlist_eff)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_EFF);
+
+        if (pde_rcvlist_sff)
+                can_remove_proc_readentry(CAN_PROC_RCVLIST_SFF);
+
+        if (can_dir)
+                proc_net_remove(&init_net, "can");
+}