patch-2.4.21 linux-2.4.21/Documentation/DocBook/journal-api.tmpl
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- Lines: 45
- Date:
2003-06-13 07:51:29.000000000 -0700
- Orig file:
linux-2.4.20/Documentation/DocBook/journal-api.tmpl
- Orig date:
2002-11-28 15:53:08.000000000 -0800
diff -urN linux-2.4.20/Documentation/DocBook/journal-api.tmpl linux-2.4.21/Documentation/DocBook/journal-api.tmpl
@@ -196,6 +196,8 @@
Lock is also providing through journal_{un,}lock_updates(),
ext3 uses this when it wants a window with a clean and stable fs for a moment.
eg.
+</para>
+
<programlisting>
journal_lock_updates() //stop new stuff happening..
@@ -204,11 +206,12 @@
journal_unlock_updates() // carry on with filesystem use.
</programlisting>
+<para>
The opportunities for abuse and DOS attacks with this should be obvious,
if you allow unprivileged userspace to trigger codepaths containing these
calls.
-<para>
+</para>
</sect1>
<sect1>
<title>Summary</title>
@@ -216,9 +219,13 @@
Using the journal is a matter of wrapping the different context changes,
being each mount, each modification (transaction) and each changed buffer
to tell the journalling layer about them.
+</para>
+<para>
Here is a some pseudo code to give you an idea of how it works, as
an example.
+</para>
+
<programlisting>
journal_t* my_jnrl = journal_create();
journal_init_{dev,inode}(jnrl,...)
@@ -244,6 +251,7 @@
}
journal_destroy(my_jrnl);
</programlisting>
+</sect1>
</chapter>
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