Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* net/atm/atm_misc.c - Various functions for use by ATM drivers */ |
2 | ||
3 | /* Written 1995-2000 by Werner Almesberger, EPFL ICA */ | |
4 | ||
1da177e4 LT |
5 | #include <linux/module.h> |
6 | #include <linux/atm.h> | |
7 | #include <linux/atmdev.h> | |
8 | #include <linux/skbuff.h> | |
9 | #include <linux/sonet.h> | |
10 | #include <linux/bitops.h> | |
3356b4d4 | 11 | #include <linux/errno.h> |
1da177e4 | 12 | #include <asm/atomic.h> |
1da177e4 | 13 | |
3356b4d4 | 14 | int atm_charge(struct atm_vcc *vcc, int truesize) |
1da177e4 | 15 | { |
3356b4d4 | 16 | atm_force_charge(vcc, truesize); |
1da177e4 LT |
17 | if (atomic_read(&sk_atm(vcc)->sk_rmem_alloc) <= sk_atm(vcc)->sk_rcvbuf) |
18 | return 1; | |
3356b4d4 | 19 | atm_return(vcc, truesize); |
1da177e4 LT |
20 | atomic_inc(&vcc->stats->rx_drop); |
21 | return 0; | |
22 | } | |
3356b4d4 | 23 | EXPORT_SYMBOL(atm_charge); |
1da177e4 | 24 | |
3356b4d4 JP |
25 | struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc, int pdu_size, |
26 | gfp_t gfp_flags) | |
1da177e4 LT |
27 | { |
28 | struct sock *sk = sk_atm(vcc); | |
29 | int guess = atm_guess_pdu2truesize(pdu_size); | |
30 | ||
3356b4d4 | 31 | atm_force_charge(vcc, guess); |
1da177e4 | 32 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) { |
3356b4d4 | 33 | struct sk_buff *skb = alloc_skb(pdu_size, gfp_flags); |
1da177e4 LT |
34 | |
35 | if (skb) { | |
36 | atomic_add(skb->truesize-guess, | |
37 | &sk->sk_rmem_alloc); | |
38 | return skb; | |
39 | } | |
40 | } | |
3356b4d4 | 41 | atm_return(vcc, guess); |
1da177e4 LT |
42 | atomic_inc(&vcc->stats->rx_drop); |
43 | return NULL; | |
44 | } | |
3356b4d4 | 45 | EXPORT_SYMBOL(atm_alloc_charge); |
1da177e4 LT |
46 | |
47 | ||
48 | /* | |
49 | * atm_pcr_goal returns the positive PCR if it should be rounded up, the | |
50 | * negative PCR if it should be rounded down, and zero if the maximum available | |
51 | * bandwidth should be used. | |
52 | * | |
53 | * The rules are as follows (* = maximum, - = absent (0), x = value "x", | |
54 | * (x+ = x or next value above x, x- = x or next value below): | |
55 | * | |
56 | * min max pcr result min max pcr result | |
57 | * - - - * (UBR only) x - - x+ | |
58 | * - - * * x - * * | |
59 | * - - z z- x - z z- | |
60 | * - * - * x * - x+ | |
61 | * - * * * x * * * | |
62 | * - * z z- x * z z- | |
63 | * - y - y- x y - x+ | |
64 | * - y * y- x y * y- | |
65 | * - y z z- x y z z- | |
66 | * | |
67 | * All non-error cases can be converted with the following simple set of rules: | |
68 | * | |
69 | * if pcr == z then z- | |
70 | * else if min == x && pcr == - then x+ | |
71 | * else if max == y then y- | |
72 | * else * | |
73 | */ | |
74 | ||
c219750b | 75 | int atm_pcr_goal(const struct atm_trafprm *tp) |
1da177e4 | 76 | { |
c219750b MBJ |
77 | if (tp->pcr && tp->pcr != ATM_MAX_PCR) |
78 | return -tp->pcr; | |
79 | if (tp->min_pcr && !tp->pcr) | |
80 | return tp->min_pcr; | |
81 | if (tp->max_pcr != ATM_MAX_PCR) | |
82 | return -tp->max_pcr; | |
1da177e4 LT |
83 | return 0; |
84 | } | |
3356b4d4 | 85 | EXPORT_SYMBOL(atm_pcr_goal); |
1da177e4 | 86 | |
3356b4d4 | 87 | void sonet_copy_stats(struct k_sonet_stats *from, struct sonet_stats *to) |
1da177e4 LT |
88 | { |
89 | #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i) | |
90 | __SONET_ITEMS | |
91 | #undef __HANDLE_ITEM | |
92 | } | |
3356b4d4 | 93 | EXPORT_SYMBOL(sonet_copy_stats); |
1da177e4 | 94 | |
3356b4d4 | 95 | void sonet_subtract_stats(struct k_sonet_stats *from, struct sonet_stats *to) |
1da177e4 | 96 | { |
3356b4d4 | 97 | #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i) |
1da177e4 LT |
98 | __SONET_ITEMS |
99 | #undef __HANDLE_ITEM | |
100 | } | |
1da177e4 | 101 | EXPORT_SYMBOL(sonet_subtract_stats); |