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