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102 lines
2.6 KiB
102 lines
2.6 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* net/atm/atm_misc.c - Various functions for use by ATM drivers */ |
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/* Written 1995-2000 by Werner Almesberger, EPFL ICA */ |
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#include <linux/module.h> |
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#include <linux/atm.h> |
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#include <linux/atmdev.h> |
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#include <linux/skbuff.h> |
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#include <linux/sonet.h> |
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#include <linux/bitops.h> |
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#include <linux/errno.h> |
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#include <linux/atomic.h> |
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int atm_charge(struct atm_vcc *vcc, int truesize) |
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{ |
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atm_force_charge(vcc, truesize); |
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if (atomic_read(&sk_atm(vcc)->sk_rmem_alloc) <= sk_atm(vcc)->sk_rcvbuf) |
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return 1; |
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atm_return(vcc, truesize); |
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atomic_inc(&vcc->stats->rx_drop); |
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return 0; |
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} |
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EXPORT_SYMBOL(atm_charge); |
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struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc, int pdu_size, |
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gfp_t gfp_flags) |
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{ |
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struct sock *sk = sk_atm(vcc); |
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int guess = SKB_TRUESIZE(pdu_size); |
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atm_force_charge(vcc, guess); |
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if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) { |
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struct sk_buff *skb = alloc_skb(pdu_size, gfp_flags); |
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if (skb) { |
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atomic_add(skb->truesize-guess, |
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&sk->sk_rmem_alloc); |
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return skb; |
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} |
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} |
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atm_return(vcc, guess); |
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atomic_inc(&vcc->stats->rx_drop); |
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return NULL; |
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} |
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EXPORT_SYMBOL(atm_alloc_charge); |
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/* |
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* atm_pcr_goal returns the positive PCR if it should be rounded up, the |
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* negative PCR if it should be rounded down, and zero if the maximum available |
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* bandwidth should be used. |
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* |
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* The rules are as follows (* = maximum, - = absent (0), x = value "x", |
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* (x+ = x or next value above x, x- = x or next value below): |
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* |
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* min max pcr result min max pcr result |
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* - - - * (UBR only) x - - x+ |
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* - - * * x - * * |
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* - - z z- x - z z- |
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* - * - * x * - x+ |
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* - * * * x * * * |
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* - * z z- x * z z- |
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* - y - y- x y - x+ |
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* - y * y- x y * y- |
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* - y z z- x y z z- |
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* |
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* All non-error cases can be converted with the following simple set of rules: |
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* |
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* if pcr == z then z- |
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* else if min == x && pcr == - then x+ |
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* else if max == y then y- |
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* else * |
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*/ |
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int atm_pcr_goal(const struct atm_trafprm *tp) |
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{ |
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if (tp->pcr && tp->pcr != ATM_MAX_PCR) |
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return -tp->pcr; |
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if (tp->min_pcr && !tp->pcr) |
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return tp->min_pcr; |
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if (tp->max_pcr != ATM_MAX_PCR) |
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return -tp->max_pcr; |
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return 0; |
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} |
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EXPORT_SYMBOL(atm_pcr_goal); |
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void sonet_copy_stats(struct k_sonet_stats *from, struct sonet_stats *to) |
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{ |
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#define __HANDLE_ITEM(i) to->i = atomic_read(&from->i) |
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__SONET_ITEMS |
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#undef __HANDLE_ITEM |
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} |
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EXPORT_SYMBOL(sonet_copy_stats); |
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void sonet_subtract_stats(struct k_sonet_stats *from, struct sonet_stats *to) |
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{ |
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#define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i) |
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__SONET_ITEMS |
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#undef __HANDLE_ITEM |
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} |
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EXPORT_SYMBOL(sonet_subtract_stats);
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