crypto-trace-events

   1 ext4 crypto: trace events for encrypt and decrypt
   2
   3 From: Michael Halcrow <mhalcrow@google.com>
   4
   5 Signed-off-by: Michael Halcrow <mhalcrow@google.com>
   6 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
   7 ---
   8  fs/ext4/crypto.c            | 34 ++++++++++++++++++++++++++++++++-
   9  include/trace/events/ext4.h | 46 +++++++++++++++++++++++++++++++++++++++++++++
  10  2 files changed, 79 insertions(+), 1 deletion(-)
  11
  12 diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
  13 index e16170f..30cfaa9 100644
  14 --- a/fs/ext4/crypto.c
  15 +++ b/fs/ext4/crypto.c
  16 @@ -31,6 +31,8 @@
  17  #include "ext4.h"
  18  #include "xattr.h"
  19
  20 +#include <trace/events/ext4.h>
  21 +
  22  /* Encryption added and removed here! (L: */
  23
  24  mempool_t *ext4_bounce_page_pool = NULL;
  25 @@ -447,6 +449,13 @@ struct page *ext4_encrypt(struct ext4_crypto_ctx *ctx,
  26                           struct page *plaintext_page)
  27  {
  28         struct page *ciphertext_page = NULL;
  29 +       char c0, c4095, p0, p4095;
  30 +       char *page_virt;
  31 +
  32 +       page_virt = kmap(plaintext_page);
  33 +       p0 = page_virt[0];
  34 +       p4095 = page_virt[PAGE_CACHE_SIZE - 1];
  35 +       kunmap(plaintext_page);
  36
  37         BUG_ON(!PageLocked(plaintext_page));
  38         switch (ctx->mode) {
  39 @@ -464,8 +473,16 @@ struct page *ext4_encrypt(struct ext4_crypto_ctx *ctx,
  40         default:
  41                 BUG();
  42         }
  43 -       if (!IS_ERR_OR_NULL(ciphertext_page))
  44 +       if (!IS_ERR_OR_NULL(ciphertext_page)) {
  45                 ext4_prep_pages_for_write(ciphertext_page, plaintext_page, ctx);
  46 +
  47 +               page_virt = kmap(ciphertext_page);
  48 +               c0 = page_virt[0];
  49 +               c4095 = page_virt[PAGE_CACHE_SIZE - 1];
  50 +               kunmap(ciphertext_page);
  51 +
  52 +               trace_ext4_encrypt(plaintext_page, p0, p4095, c0, c4095);
  53 +       }
  54         return ciphertext_page;
  55  }
  56
  57 @@ -549,6 +566,13 @@ bool __ext4_debug_is_page_zero(struct page *page)
  58  int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page)
  59  {
  60         int res = 0;
  61 +       char c0, c4095, p0, p4095;
  62 +       char *page_virt;
  63 +
  64 +       page_virt = kmap(page);
  65 +       c0 = page_virt[0];
  66 +       c4095 = page_virt[PAGE_CACHE_SIZE - 1];
  67 +       kunmap(page);
  68
  69         BUG_ON(!PageLocked(page));
  70         BUG_ON(__ext4_debug_is_page_zero(page));
  71 @@ -564,6 +588,14 @@ int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page)
  72         default:
  73                 BUG();
  74         }
  75 +
  76 +       page_virt = kmap(page);
  77 +       p0 = page_virt[0];
  78 +       p4095 = page_virt[PAGE_CACHE_SIZE - 1];
  79 +       kunmap(page);
  80 +
  81 +       trace_ext4_decrypt(page, p0, p4095, c0, c4095);
  82 +
  83         return res;
  84  }
  85
  86 diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
  87 index d4f70a7..91835b1 100644
  88 --- a/include/trace/events/ext4.h
  89 +++ b/include/trace/events/ext4.h
  90 @@ -494,6 +494,38 @@ DECLARE_EVENT_CLASS(ext4__page_op,
  91                   (unsigned long) __entry->index)
  92  );
  93
  94 +DECLARE_EVENT_CLASS(ext4__page_crypt_op,
  95 +       TP_PROTO(struct page *page, char p0, char p4095, char c0, char c4095),
  96 +
  97 +       TP_ARGS(page, p0, p4095, c0, c4095),
  98 +
  99 +       TP_STRUCT__entry(
 100 +               __field(        ino_t,  ino                     )
 101 +               __field(        pgoff_t, index                  )
 102 +               __field(        char,   p0                      )
 103 +               __field(        char,   p4095                   )
 104 +               __field(        char,   c0                      )
 105 +               __field(        char,   c4095                   )
 106 +       ),
 107 +
 108 +       TP_fast_assign(
 109 +               __entry->ino    = page->mapping->host->i_ino;
 110 +               __entry->index  = page->index;
 111 +               __entry->p0     = p0;
 112 +               __entry->p4095  = p4095;
 113 +               __entry->c0     = c0;
 114 +               __entry->c4095  = c4095;
 115 +       ),
 116 +
 117 +       TP_printk("ino %lu page_index %lu p0 %.2x p4095 %.2x c0 %.2x c4095 %.2x",
 118 +                 (unsigned long) __entry->ino,
 119 +                 (unsigned long) __entry->index,
 120 +                 (unsigned char) __entry->p0,
 121 +                 (unsigned char) __entry->p4095,
 122 +                 (unsigned char) __entry->c0,
 123 +                 (unsigned char) __entry->c4095)
 124 +);
 125 +
 126  DEFINE_EVENT(ext4__page_op, ext4_writepage,
 127
 128         TP_PROTO(struct page *page),
 129 @@ -515,6 +547,20 @@ DEFINE_EVENT(ext4__page_op, ext4_releasepage,
 130         TP_ARGS(page)
 131  );
 132
 133 +DEFINE_EVENT(ext4__page_crypt_op, ext4_encrypt,
 134 +
 135 +       TP_PROTO(struct page *page, char p0, char p4095, char c0, char c4095),
 136 +
 137 +       TP_ARGS(page, p0, p4095, c0, c4095)
 138 +);
 139 +
 140 +DEFINE_EVENT(ext4__page_crypt_op, ext4_decrypt,
 141 +
 142 +       TP_PROTO(struct page *page, char p0, char p4095, char c0, char c4095),
 143 +
 144 +       TP_ARGS(page, p0, p4095, c0, c4095)
 145 +);
 146 +
 147  DECLARE_EVENT_CLASS(ext4_invalidatepage_op,
 148         TP_PROTO(struct page *page, unsigned int offset, unsigned int length),
 149
 150 --
 151 2.1.0.rc2.206.gedb03e5
 152
 153