package/kernel/mac80211/patches/013-backport-dev_coredumpm-function.patch

   1 From ec8549e611465558bdf1bb5e9d308f39e5e248cd Mon Sep 17 00:00:00 2001
   2 From: Hauke Mehrtens <hauke@hauke-m.de>
   3 Date: Sun, 17 Sep 2017 14:41:48 +0200
   4 Subject: backport dev_coredumpm() function
   5
   6 This is copied from a more recent backports version to add the
   7 dev_coredumpm() function when the internal core devdump is not used.
   8 ---
   9  compat/Makefile                |  1 +
  10  compat/backport-4.7.c          | 82 ++++++++++++++++++++++++++++++++++++++++++
  11  include/linux/bp-devcoredump.h | 32 +++++++++++++++++
  12  include/linux/devcoredump.h    |  1 +
  13  4 files changed, 116 insertions(+)
  14  create mode 100644 compat/backport-4.7.c
  15  create mode 100644 include/linux/bp-devcoredump.h
  16
  17 --- a/compat/Makefile
  18 +++ b/compat/Makefile
  19 @@ -32,6 +32,7 @@ compat-$(CPTCFG_KERNEL_4_3) += backport-
  20  compat-$(CPTCFG_KERNEL_4_4) += backport-4.4.o
  21  compat-$(CPTCFG_KERNEL_4_5) += backport-4.5.o
  22  compat-$(CPTCFG_KERNEL_4_6) += backport-4.6.o
  23 +compat-$(CPTCFG_KERNEL_4_6) += backport-4.7.o
  24
  25  compat-$(CPTCFG_BPAUTO_BUILD_CRYPTO_CCM) += crypto-ccm.o
  26  compat-$(CPTCFG_BPAUTO_CRYPTO_SKCIPHER) += crypto-skcipher.o
  27 --- /dev/null
  28 +++ b/compat/backport-4.7.c
  29 @@ -0,0 +1,82 @@
  30 +/*
  31 + * Copyright(c) 2016 Hauke Mehrtens <hauke@hauke-m.de>
  32 + *
  33 + * Backport functionality introduced in Linux 4.7.
  34 + *
  35 + * This program is free software; you can redistribute it and/or modify
  36 + * it under the terms of the GNU General Public License version 2 as
  37 + * published by the Free Software Foundation.
  38 + */
  39 +
  40 +#include <linux/export.h>
  41 +#include <linux/list.h>
  42 +#include <linux/rcupdate.h>
  43 +#include <linux/slab.h>
  44 +#include <linux/spinlock.h>
  45 +#include <linux/skbuff.h>
  46 +#include <net/netlink.h>
  47 +
  48 +/*
  49 + * Below 3.18 or if the kernel has devcoredump disabled, we copied the
  50 + * entire devcoredump, so no need to define these functions.
  51 + */
  52 +#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,18,0) && \
  53 +       !defined(CPTCFG_BPAUTO_BUILD_WANT_DEV_COREDUMP)
  54 +#include <linux/devcoredump.h>
  55 +#include <linux/scatterlist.h>
  56 +
  57 +static void devcd_free_sgtable(void *data)
  58 +{
  59 +       struct scatterlist *table = data;
  60 +       int i;
  61 +       struct page *page;
  62 +       struct scatterlist *iter;
  63 +       struct scatterlist *delete_iter;
  64 +
  65 +       /* free pages */
  66 +       iter = table;
  67 +       for_each_sg(table, iter, sg_nents(table), i) {
  68 +               page = sg_page(iter);
  69 +               if (page)
  70 +                       __free_page(page);
  71 +       }
  72 +
  73 +       /* then free all chained tables */
  74 +       iter = table;
  75 +       delete_iter = table;    /* always points on a head of a table */
  76 +       while (!sg_is_last(iter)) {
  77 +               iter++;
  78 +               if (sg_is_chain(iter)) {
  79 +                       iter = sg_chain_ptr(iter);
  80 +                       kfree(delete_iter);
  81 +                       delete_iter = iter;
  82 +               }
  83 +       }
  84 +
  85 +       /* free the last table */
  86 +       kfree(delete_iter);
  87 +}
  88 +
  89 +static ssize_t devcd_read_from_sgtable(char *buffer, loff_t offset,
  90 +                                      size_t buf_len, void *data,
  91 +                                      size_t data_len)
  92 +{
  93 +       struct scatterlist *table = data;
  94 +
  95 +       if (offset > data_len)
  96 +               return -EINVAL;
  97 +
  98 +       if (offset + buf_len > data_len)
  99 +               buf_len = data_len - offset;
 100 +       return sg_pcopy_to_buffer(table, sg_nents(table), buffer, buf_len,
 101 +                                 offset);
 102 +}
 103 +
 104 +void dev_coredumpsg(struct device *dev, struct scatterlist *table,
 105 +                   size_t datalen, gfp_t gfp)
 106 +{
 107 +       dev_coredumpm(dev, THIS_MODULE, table, datalen, gfp,
 108 +                     devcd_read_from_sgtable, devcd_free_sgtable);
 109 +}
 110 +EXPORT_SYMBOL_GPL(dev_coredumpsg);
 111 +#endif /* >= 3.18.0 */
 112 --- /dev/null
 113 +++ b/include/linux/bp-devcoredump.h
 114 @@ -0,0 +1,32 @@
 115 +#ifndef __BACKPORT_LINUX_DEVCOREDUMP_H
 116 +#define __BACKPORT_LINUX_DEVCOREDUMP_H
 117 +#include <linux/version.h>
 118 +#include <linux/scatterlist.h>
 119 +
 120 +/* We only need to add our wrapper inside the range from 3.18 until
 121 + * 4.6, outside that we can let our BPAUTO mechanism handle it.
 122 + */
 123 +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,18,0)  &&  \
 124 +     LINUX_VERSION_CODE < KERNEL_VERSION(4,7,0))
 125 +static inline
 126 +void backport_dev_coredumpm(struct device *dev, struct module *owner,
 127 +                           void *data, size_t datalen, gfp_t gfp,
 128 +                           ssize_t (*read_fn)(char *buffer, loff_t offset,
 129 +                                           size_t count, void *data,
 130 +                                           size_t datalen),
 131 +                           void (*free_fn)(void *data))
 132 +{
 133 +       return dev_coredumpm(dev, owner, (const void *)data, datalen, gfp,
 134 +                            (void *)read_fn, (void *)free_fn);
 135 +}
 136 +
 137 +#define dev_coredumpm LINUX_BACKPORT(dev_coredumpm)
 138 +
 139 +#define dev_coredumpsg LINUX_BACKPORT(dev_coredumpsg)
 140 +void dev_coredumpsg(struct device *dev, struct scatterlist *table,
 141 +                   size_t datalen, gfp_t gfp);
 142 +
 143 +#endif /* (LINUX_VERSION_IS_GEQ(3,18,0) &&     \
 144 +          LINUX_VERSION_IS_LESS(4,7,0)) */
 145 +
 146 +#endif /* __BACKPORT_LINUX_DEVCOREDUMP_H */
 147 --- a/include/linux/devcoredump.h
 148 +++ b/include/linux/devcoredump.h
 149 @@ -1,6 +1,7 @@
 150  /* Automatically created during backport process */
 151  #ifndef CPTCFG_BPAUTO_BUILD_WANT_DEV_COREDUMP
 152  #include_next <linux/devcoredump.h>
 153 +#include <linux/bp-devcoredump.h>
 154  #else
 155  #undef dev_coredumpv
 156  #define dev_coredumpv LINUX_BACKPORT(dev_coredumpv)