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