Nick Piggin wrote:
> On Thu, Nov 27, 2008 at 05:34:26PM +0300, Edward Shishkin wrote:
>
>> reiser4_write_{begin,end} works only in splice.c (i.e. only for
>> loopback functionality) in the chunk of code which looks like this:
>>
>> pagecache_write_begin();
>> ...
>> memcpy(.., to_page);
>> ...
>> pagecache_write_end(.., to_page, ..);
>>
>> i.e. there can not be short writes and everything is uptodate.
>>
>
> Ah OK, indeed you are right. Although that's not to say that some
> other kernel code may not be able to start doing interruptible
> copies, although it would be fairly unlikely. Maybe if you just have
> a BUG_ON(!(flags & AOP_FLAG_UNINTERRUPTIBLE)); or something to just
> make sure?
Yup, I would say, it's a must..
Thanks,
Edward.
Make sure that reiser4_write_begin()
is not called for interruptible copies.
Signed-off-by: Edward Shishkin<edward.shishkin@xxxxxxxxx>
---
linux-2.6.28-rc2-mm1/fs/reiser4/plugin/file/file_conversion.c | 6 ++++++
1 file changed, 6 insertions(+)
--- linux-2.6.28-rc2-mm1/fs/reiser4/plugin/file/file_conversion.c.orig
+++ linux-2.6.28-rc2-mm1/fs/reiser4/plugin/file/file_conversion.c
@@ -682,6 +682,12 @@ int reiser4_write_begin_careful(struct f
reiser4_context *ctx;
struct inode * inode = file->f_dentry->d_inode;
+ /**
+ * reiser4_write_end() can not cope with
+ * short writes for now
+ */
+ BUG_ON(!(flags & AOP_FLAG_UNINTERRUPTIBLE));
+
index = pos >> PAGE_CACHE_SHIFT;
start = pos & (PAGE_CACHE_SIZE - 1);
end = start + len;
