net/core/gen_stats.c

   1 /*
   2  * net/core/gen_stats.c
   3  *
   4  *             This program is free software; you can redistribute it and/or
   5  *             modify it under the terms of the GNU General Public License
   6  *             as published by the Free Software Foundation; either version
   7  *             2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:  Thomas Graf <tgraf@suug.ch>
  10  *           Jamal Hadi Salim
  11  *           Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  12  *
  13  * See Documentation/networking/gen_stats.txt
  14  */
  15
  16 #include <linux/types.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/socket.h>
  21 #include <linux/rtnetlink.h>
  22 #include <linux/gen_stats.h>
  23 #include <net/netlink.h>
  24 #include <net/gen_stats.h>
  25
  26
  27 static inline int
  28 gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size)
  29 {
  30         if (nla_put(d->skb, type, size, buf))
  31                 goto nla_put_failure;
  32         return 0;
  33
  34 nla_put_failure:
  35         spin_unlock_bh(d->lock);
  36         return -1;
  37 }
  38
  39 /**
  40  * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
  41  * @skb: socket buffer to put statistics TLVs into
  42  * @type: TLV type for top level statistic TLV
  43  * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
  44  * @xstats_type: TLV type for backward compatibility xstats TLV
  45  * @lock: statistics lock
  46  * @d: dumping handle
  47  *
  48  * Initializes the dumping handle, grabs the statistic lock and appends
  49  * an empty TLV header to the socket buffer for use a container for all
  50  * other statistic TLVS.
  51  *
  52  * The dumping handle is marked to be in backward compatibility mode telling
  53  * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
  54  *
  55  * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
  56  */
  57 int
  58 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
  59         int xstats_type, spinlock_t *lock, struct gnet_dump *d)
  60         __acquires(lock)
  61 {
  62         memset(d, 0, sizeof(*d));
  63
  64         spin_lock_bh(lock);
  65         d->lock = lock;
  66         if (type)
  67                 d->tail = (struct nlattr *)skb_tail_pointer(skb);
  68         d->skb = skb;
  69         d->compat_tc_stats = tc_stats_type;
  70         d->compat_xstats = xstats_type;
  71
  72         if (d->tail)
  73                 return gnet_stats_copy(d, type, NULL, 0);
  74
  75         return 0;
  76 }
  77 EXPORT_SYMBOL(gnet_stats_start_copy_compat);
  78
  79 /**
  80  * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
  81  * @skb: socket buffer to put statistics TLVs into
  82  * @type: TLV type for top level statistic TLV
  83  * @lock: statistics lock
  84  * @d: dumping handle
  85  *
  86  * Initializes the dumping handle, grabs the statistic lock and appends
  87  * an empty TLV header to the socket buffer for use a container for all
  88  * other statistic TLVS.
  89  *
  90  * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
  91  */
  92 int
  93 gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
  94         struct gnet_dump *d)
  95 {
  96         return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d);
  97 }
  98 EXPORT_SYMBOL(gnet_stats_start_copy);
  99
 100 /**
 101  * gnet_stats_copy_basic - copy basic statistics into statistic TLV
 102  * @d: dumping handle
 103  * @b: basic statistics
 104  *
 105  * Appends the basic statistics to the top level TLV created by
 106  * gnet_stats_start_copy().
 107  *
 108  * Returns 0 on success or -1 with the statistic lock released
 109  * if the room in the socket buffer was not sufficient.
 110  */
 111 int
 112 gnet_stats_copy_basic(struct gnet_dump *d, struct gnet_stats_basic_packed *b)
 113 {
 114         if (d->compat_tc_stats) {
 115                 d->tc_stats.bytes = b->bytes;
 116                 d->tc_stats.packets = b->packets;
 117         }
 118
 119         if (d->tail) {
 120                 struct gnet_stats_basic sb;
 121
 122                 memset(&sb, 0, sizeof(sb));
 123                 sb.bytes = b->bytes;
 124                 sb.packets = b->packets;
 125                 return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb));
 126         }
 127         return 0;
 128 }
 129 EXPORT_SYMBOL(gnet_stats_copy_basic);
 130
 131 /**
 132  * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
 133  * @d: dumping handle
 134  * @b: basic statistics
 135  * @r: rate estimator statistics
 136  *
 137  * Appends the rate estimator statistics to the top level TLV created by
 138  * gnet_stats_start_copy().
 139  *
 140  * Returns 0 on success or -1 with the statistic lock released
 141  * if the room in the socket buffer was not sufficient.
 142  */
 143 int
 144 gnet_stats_copy_rate_est(struct gnet_dump *d,
 145                          const struct gnet_stats_basic_packed *b,
 146                          struct gnet_stats_rate_est *r)
 147 {
 148         if (b && !gen_estimator_active(b, r))
 149                 return 0;
 150
 151         if (d->compat_tc_stats) {
 152                 d->tc_stats.bps = r->bps;
 153                 d->tc_stats.pps = r->pps;
 154         }
 155
 156         if (d->tail)
 157                 return gnet_stats_copy(d, TCA_STATS_RATE_EST, r, sizeof(*r));
 158
 159         return 0;
 160 }
 161 EXPORT_SYMBOL(gnet_stats_copy_rate_est);
 162
 163 /**
 164  * gnet_stats_copy_queue - copy queue statistics into statistics TLV
 165  * @d: dumping handle
 166  * @q: queue statistics
 167  *
 168  * Appends the queue statistics to the top level TLV created by
 169  * gnet_stats_start_copy().
 170  *
 171  * Returns 0 on success or -1 with the statistic lock released
 172  * if the room in the socket buffer was not sufficient.
 173  */
 174 int
 175 gnet_stats_copy_queue(struct gnet_dump *d, struct gnet_stats_queue *q)
 176 {
 177         if (d->compat_tc_stats) {
 178                 d->tc_stats.drops = q->drops;
 179                 d->tc_stats.qlen = q->qlen;
 180                 d->tc_stats.backlog = q->backlog;
 181                 d->tc_stats.overlimits = q->overlimits;
 182         }
 183
 184         if (d->tail)
 185                 return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
 186
 187         return 0;
 188 }
 189 EXPORT_SYMBOL(gnet_stats_copy_queue);
 190
 191 /**
 192  * gnet_stats_copy_app - copy application specific statistics into statistics TLV
 193  * @d: dumping handle
 194  * @st: application specific statistics data
 195  * @len: length of data
 196  *
 197  * Appends the application sepecific statistics to the top level TLV created by
 198  * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
 199  * handle is in backward compatibility mode.
 200  *
 201  * Returns 0 on success or -1 with the statistic lock released
 202  * if the room in the socket buffer was not sufficient.
 203  */
 204 int
 205 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len)
 206 {
 207         if (d->compat_xstats) {
 208                 d->xstats = st;
 209                 d->xstats_len = len;
 210         }
 211
 212         if (d->tail)
 213                 return gnet_stats_copy(d, TCA_STATS_APP, st, len);
 214
 215         return 0;
 216 }
 217 EXPORT_SYMBOL(gnet_stats_copy_app);
 218
 219 /**
 220  * gnet_stats_finish_copy - finish dumping procedure
 221  * @d: dumping handle
 222  *
 223  * Corrects the length of the top level TLV to include all TLVs added
 224  * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
 225  * if gnet_stats_start_copy_compat() was used and releases the statistics
 226  * lock.
 227  *
 228  * Returns 0 on success or -1 with the statistic lock released
 229  * if the room in the socket buffer was not sufficient.
 230  */
 231 int
 232 gnet_stats_finish_copy(struct gnet_dump *d)
 233 {
 234         if (d->tail)
 235                 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
 236
 237         if (d->compat_tc_stats)
 238                 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
 239                         sizeof(d->tc_stats)) < 0)
 240                         return -1;
 241
 242         if (d->compat_xstats && d->xstats) {
 243                 if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
 244                         d->xstats_len) < 0)
 245                         return -1;
 246         }
 247
 248         spin_unlock_bh(d->lock);
 249         return 0;
 250 }
 251 EXPORT_SYMBOL(gnet_stats_finish_copy);