include/linux/devcoredump.h

   1 /*
   2  * This file is provided under the GPLv2 license.
   3  *
   4  * GPL LICENSE SUMMARY
   5  *
   6  * Copyright(c) 2015 Intel Deutschland GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * The full GNU General Public License is included in this distribution
  18  * in the file called COPYING.
  19  */
  20 #ifndef __DEVCOREDUMP_H
  21 #define __DEVCOREDUMP_H
  22
  23 #include <linux/device.h>
  24 #include <linux/module.h>
  25 #include <linux/vmalloc.h>
  26
  27 #include <linux/scatterlist.h>
  28 #include <linux/slab.h>
  29
  30 /*
  31  * _devcd_free_sgtable - free all the memory of the given scatterlist table
  32  * (i.e. both pages and scatterlist instances)
  33  * NOTE: if two tables allocated and chained using the sg_chain function then
  34  * this function should be called only once on the first table
  35  * @table: pointer to sg_table to free
  36  */
  37 static inline void _devcd_free_sgtable(struct scatterlist *table)
  38 {
  39         int i;
  40         struct page *page;
  41         struct scatterlist *iter;
  42         struct scatterlist *delete_iter;
  43
  44         /* free pages */
  45         iter = table;
  46         for_each_sg(table, iter, sg_nents(table), i) {
  47                 page = sg_page(iter);
  48                 if (page)
  49                         __free_page(page);
  50         }
  51
  52         /* then free all chained tables */
  53         iter = table;
  54         delete_iter = table;    /* always points on a head of a table */
  55         while (!sg_is_last(iter)) {
  56                 iter++;
  57                 if (sg_is_chain(iter)) {
  58                         iter = sg_chain_ptr(iter);
  59                         kfree(delete_iter);
  60                         delete_iter = iter;
  61                 }
  62         }
  63
  64         /* free the last table */
  65         kfree(delete_iter);
  66 }
  67
  68
  69 #ifdef CONFIG_DEV_COREDUMP
  70 void dev_coredumpv(struct device *dev, void *data, size_t datalen,
  71                    gfp_t gfp);
  72
  73 void dev_coredumpm(struct device *dev, struct module *owner,
  74                    void *data, size_t datalen, gfp_t gfp,
  75                    ssize_t (*read)(char *buffer, loff_t offset, size_t count,
  76                                    void *data, size_t datalen),
  77                    void (*free)(void *data));
  78
  79 void dev_coredumpsg(struct device *dev, struct scatterlist *table,
  80                     size_t datalen, gfp_t gfp);
  81 #else
  82 static inline void dev_coredumpv(struct device *dev, void *data,
  83                                  size_t datalen, gfp_t gfp)
  84 {
  85         vfree(data);
  86 }
  87
  88 static inline void
  89 dev_coredumpm(struct device *dev, struct module *owner,
  90               void *data, size_t datalen, gfp_t gfp,
  91               ssize_t (*read)(char *buffer, loff_t offset, size_t count,
  92                               void *data, size_t datalen),
  93               void (*free)(void *data))
  94 {
  95         free(data);
  96 }
  97
  98 static inline void dev_coredumpsg(struct device *dev, struct scatterlist *table,
  99                                   size_t datalen, gfp_t gfp)
 100 {
 101         _devcd_free_sgtable(table);
 102 }
 103 #endif /* CONFIG_DEV_COREDUMP */
 104
 105 #endif /* __DEVCOREDUMP_H */