drivers/staging/unisys/uislib/uisutils.c

   1 /* uisutils.c
   2  *
   3  * Copyright (C) 2010 - 2013 UNISYS CORPORATION
   4  * All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or (at
   9  * your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  14  * NON INFRINGEMENT.  See the GNU General Public License for more
  15  * details.
  16  */
  17
  18 #include <linux/string.h>
  19 #include <linux/slab.h>
  20 #include <linux/types.h>
  21 #include <linux/uuid.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/list.h>
  24 #include "uniklog.h"
  25 #include "uisutils.h"
  26 #include "version.h"
  27 #include "vbushelper.h"
  28 #include <linux/skbuff.h>
  29 #ifdef CONFIG_HIGHMEM
  30 #include <linux/highmem.h>
  31 #endif
  32
  33 /* this is shorter than using __FILE__ (full path name) in
  34  * debug/info/error messages
  35  */
  36 #define CURRENT_FILE_PC UISLIB_PC_uisutils_c
  37 #define __MYFILE__ "uisutils.c"
  38
  39 /* exports */
  40 atomic_t uisutils_registered_services = ATOMIC_INIT(0);
  41                                         /* num registrations via
  42                                          * uisctrl_register_req_handler() or
  43                                          * uisctrl_register_req_handler_ex() */
  44
  45 /*****************************************************/
  46 /* Utility functions                                 */
  47 /*****************************************************/
  48
  49 int
  50 uisutil_add_proc_line_ex(int *total, char **buffer, int *buffer_remaining,
  51                          char *format, ...)
  52 {
  53         va_list args;
  54         int len;
  55
  56         va_start(args, format);
  57         len = vsnprintf(*buffer, *buffer_remaining, format, args);
  58         va_end(args);
  59         if (len >= *buffer_remaining) {
  60                 *buffer += *buffer_remaining;
  61                 *total += *buffer_remaining;
  62                 *buffer_remaining = 0;
  63                 return -1;
  64         }
  65         *buffer_remaining -= len;
  66         *buffer += len;
  67         *total += len;
  68         return len;
  69 }
  70 EXPORT_SYMBOL_GPL(uisutil_add_proc_line_ex);
  71
  72 int
  73 uisctrl_register_req_handler(int type, void *fptr,
  74                              struct ultra_vbus_deviceinfo *chipset_driver_info)
  75 {
  76         switch (type) {
  77         case 2:
  78                 if (fptr) {
  79                         if (!virt_control_chan_func)
  80                                 atomic_inc(&uisutils_registered_services);
  81                         virt_control_chan_func = fptr;
  82                 } else {
  83                         if (virt_control_chan_func)
  84                                 atomic_dec(&uisutils_registered_services);
  85                         virt_control_chan_func = NULL;
  86                 }
  87                 break;
  88
  89         default:
  90                 return 0;
  91         }
  92         if (chipset_driver_info)
  93                 bus_device_info_init(chipset_driver_info, "chipset", "uislib",
  94                                      VERSION, NULL);
  95
  96         return 1;
  97 }
  98 EXPORT_SYMBOL_GPL(uisctrl_register_req_handler);
  99
 100 /*
 101  * unsigned int uisutil_copy_fragsinfo_from_skb(unsigned char *calling_ctx,
 102  *                                           void *skb_in,
 103  *                                           unsigned int firstfraglen,
 104  *                                           unsigned int frags_max,
 105  *                                           struct phys_info frags[])
 106  *
 107  *      calling_ctx - input -   a string that is displayed to show
 108  *                              who called * this func
 109  *      void *skb_in -  skb whose frag info we're copying type is hidden so we
 110  *                      don't need to include skbbuff in uisutils.h which is
 111  *                      included in non-networking code.
 112  *      unsigned int firstfraglen - input - length of first fragment in skb
 113  *      unsigned int frags_max - input - max len of frags array
 114  *      struct phys_info frags[] - output - frags array filled in on output
 115  *                                          return value indicates number of
 116  *                                          entries filled in frags
 117  */
 118
 119 static LIST_HEAD(req_handler_info_list); /* list of struct req_handler_info */
 120 static DEFINE_SPINLOCK(req_handler_info_list_lock);
 121
 122 struct req_handler_info *
 123 req_handler_find(uuid_le switch_uuid)
 124 {
 125         struct list_head *lelt, *tmp;
 126         struct req_handler_info *entry = NULL;
 127
 128         spin_lock(&req_handler_info_list_lock);
 129         list_for_each_safe(lelt, tmp, &req_handler_info_list) {
 130                 entry = list_entry(lelt, struct req_handler_info, list_link);
 131                 if (uuid_le_cmp(entry->switch_uuid, switch_uuid) == 0) {
 132                         spin_unlock(&req_handler_info_list_lock);
 133                         return entry;
 134                 }
 135         }
 136         spin_unlock(&req_handler_info_list_lock);
 137         return NULL;
 138 }