drivers/isdn/capi/capilib.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <linux/slab.h>
   4 #include <linux/kernel.h>
   5 #include <linux/module.h>
   6 #include <linux/isdn/capilli.h>
   7
   8 #define DBG(format, arg...) do {                                        \
   9                 printk(KERN_DEBUG "%s: " format "\n" , __func__ , ## arg); \
  10         } while (0)
  11
  12 struct capilib_msgidqueue {
  13         struct capilib_msgidqueue *next;
  14         u16 msgid;
  15 };
  16
  17 struct capilib_ncci {
  18         struct list_head list;
  19         u16 applid;
  20         u32 ncci;
  21         u32 winsize;
  22         int   nmsg;
  23         struct capilib_msgidqueue *msgidqueue;
  24         struct capilib_msgidqueue *msgidlast;
  25         struct capilib_msgidqueue *msgidfree;
  26         struct capilib_msgidqueue msgidpool[CAPI_MAXDATAWINDOW];
  27 };
  28
  29 // ---------------------------------------------------------------------------
  30 // NCCI Handling
  31
  32 static inline void mq_init(struct capilib_ncci *np)
  33 {
  34         u_int i;
  35         np->msgidqueue = NULL;
  36         np->msgidlast = NULL;
  37         np->nmsg = 0;
  38         memset(np->msgidpool, 0, sizeof(np->msgidpool));
  39         np->msgidfree = &np->msgidpool[0];
  40         for (i = 1; i < np->winsize; i++) {
  41                 np->msgidpool[i].next = np->msgidfree;
  42                 np->msgidfree = &np->msgidpool[i];
  43         }
  44 }
  45
  46 static inline int mq_enqueue(struct capilib_ncci *np, u16 msgid)
  47 {
  48         struct capilib_msgidqueue *mq;
  49         if ((mq = np->msgidfree) == NULL)
  50                 return 0;
  51         np->msgidfree = mq->next;
  52         mq->msgid = msgid;
  53         mq->next = NULL;
  54         if (np->msgidlast)
  55                 np->msgidlast->next = mq;
  56         np->msgidlast = mq;
  57         if (!np->msgidqueue)
  58                 np->msgidqueue = mq;
  59         np->nmsg++;
  60         return 1;
  61 }
  62
  63 static inline int mq_dequeue(struct capilib_ncci *np, u16 msgid)
  64 {
  65         struct capilib_msgidqueue **pp;
  66         for (pp = &np->msgidqueue; *pp; pp = &(*pp)->next) {
  67                 if ((*pp)->msgid == msgid) {
  68                         struct capilib_msgidqueue *mq = *pp;
  69                         *pp = mq->next;
  70                         if (mq == np->msgidlast)
  71                                 np->msgidlast = NULL;
  72                         mq->next = np->msgidfree;
  73                         np->msgidfree = mq;
  74                         np->nmsg--;
  75                         return 1;
  76                 }
  77         }
  78         return 0;
  79 }
  80
  81 void capilib_new_ncci(struct list_head *head, u16 applid, u32 ncci, u32 winsize)
  82 {
  83         struct capilib_ncci *np;
  84
  85         np = kmalloc(sizeof(*np), GFP_ATOMIC);
  86         if (!np) {
  87                 printk(KERN_WARNING "capilib_new_ncci: no memory.\n");
  88                 return;
  89         }
  90         if (winsize > CAPI_MAXDATAWINDOW) {
  91                 printk(KERN_ERR "capi_new_ncci: winsize %d too big\n",
  92                        winsize);
  93                 winsize = CAPI_MAXDATAWINDOW;
  94         }
  95         np->applid = applid;
  96         np->ncci = ncci;
  97         np->winsize = winsize;
  98         mq_init(np);
  99         list_add_tail(&np->list, head);
 100         DBG("kcapi: appl %d ncci 0x%x up", applid, ncci);
 101 }
 102
 103 EXPORT_SYMBOL(capilib_new_ncci);
 104
 105 void capilib_free_ncci(struct list_head *head, u16 applid, u32 ncci)
 106 {
 107         struct list_head *l;
 108         struct capilib_ncci *np;
 109
 110         list_for_each(l, head) {
 111                 np = list_entry(l, struct capilib_ncci, list);
 112                 if (np->applid != applid)
 113                         continue;
 114                 if (np->ncci != ncci)
 115                         continue;
 116                 printk(KERN_INFO "kcapi: appl %d ncci 0x%x down\n", applid, ncci);
 117                 list_del(&np->list);
 118                 kfree(np);
 119                 return;
 120         }
 121         printk(KERN_ERR "capilib_free_ncci: ncci 0x%x not found\n", ncci);
 122 }
 123
 124 EXPORT_SYMBOL(capilib_free_ncci);
 125
 126 void capilib_release_appl(struct list_head *head, u16 applid)
 127 {
 128         struct list_head *l, *n;
 129         struct capilib_ncci *np;
 130
 131         list_for_each_safe(l, n, head) {
 132                 np = list_entry(l, struct capilib_ncci, list);
 133                 if (np->applid != applid)
 134                         continue;
 135                 printk(KERN_INFO "kcapi: appl %d ncci 0x%x forced down\n", applid, np->ncci);
 136                 list_del(&np->list);
 137                 kfree(np);
 138         }
 139 }
 140
 141 EXPORT_SYMBOL(capilib_release_appl);
 142
 143 void capilib_release(struct list_head *head)
 144 {
 145         struct list_head *l, *n;
 146         struct capilib_ncci *np;
 147
 148         list_for_each_safe(l, n, head) {
 149                 np = list_entry(l, struct capilib_ncci, list);
 150                 printk(KERN_INFO "kcapi: appl %d ncci 0x%x forced down\n", np->applid, np->ncci);
 151                 list_del(&np->list);
 152                 kfree(np);
 153         }
 154 }
 155
 156 EXPORT_SYMBOL(capilib_release);
 157
 158 u16 capilib_data_b3_req(struct list_head *head, u16 applid, u32 ncci, u16 msgid)
 159 {
 160         struct list_head *l;
 161         struct capilib_ncci *np;
 162
 163         list_for_each(l, head) {
 164                 np = list_entry(l, struct capilib_ncci, list);
 165                 if (np->applid != applid)
 166                         continue;
 167                 if (np->ncci != ncci)
 168                         continue;
 169
 170                 if (mq_enqueue(np, msgid) == 0)
 171                         return CAPI_SENDQUEUEFULL;
 172
 173                 return CAPI_NOERROR;
 174         }
 175         printk(KERN_ERR "capilib_data_b3_req: ncci 0x%x not found\n", ncci);
 176         return CAPI_NOERROR;
 177 }
 178
 179 EXPORT_SYMBOL(capilib_data_b3_req);
 180
 181 void capilib_data_b3_conf(struct list_head *head, u16 applid, u32 ncci, u16 msgid)
 182 {
 183         struct list_head *l;
 184         struct capilib_ncci *np;
 185
 186         list_for_each(l, head) {
 187                 np = list_entry(l, struct capilib_ncci, list);
 188                 if (np->applid != applid)
 189                         continue;
 190                 if (np->ncci != ncci)
 191                         continue;
 192
 193                 if (mq_dequeue(np, msgid) == 0) {
 194                         printk(KERN_ERR "kcapi: msgid %hu ncci 0x%x not on queue\n",
 195                                msgid, ncci);
 196                 }
 197                 return;
 198         }
 199         printk(KERN_ERR "capilib_data_b3_conf: ncci 0x%x not found\n", ncci);
 200 }
 201
 202 EXPORT_SYMBOL(capilib_data_b3_conf);