[linux-cifs-client] Re: Slow transfer with mount.cifs

[Steve French]

Nicki Messerschmidt wrote:

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>On Sat, 31 Dec 2005, Steve French wrote:
>  
>
>>allows 52K writes (13 pages) rather than 4K writes - cifs 1.39a e.g. may
>>help a lot with write sizes.
>>    
>>
>I now tried to build the 1.39a againt my 2.6.14.3 kernel. But when I try
>to load this module I get:
>cifs: Unknown symbol __pagevec_release
>cifs: Unknown symbol pagevec_lookup_tag
>
>Do you have an idea on how to fix this? I just copied the extracted
>source to
>/usr/src/linux-2.6.14.3/fs/cifs
>and started a "make clean; make bzImage; make modules; make
>modules_install". The "depmod -a" said nothing, but when loading the
>module the afore mentioned messages are in "dmesg".
>
>As of now the 2.6.14.3 kernel is not that old and it takes a while to
>find the source for the modules on http://linux-cifs.samba.org. I now
>took the source from http://pserver.samba.org/samba/ftp/cifs-cvs/. Is
>this the right place?
>
>
>  
>
There were various distro kernels (and the mm based kernels) which 
already exported __pagevec_release for experimental filesystems which 
were not in mainline, but for mainline cifs these exports were not added 
until the cifs writepages update went into 2.6.15 (since cifs writepages 
requires these two exports).   If you can rebuild the kernel bzImage 
then it is easy enough to either
a) build cifs into bzImage instead of as a module
or
b) add the two line change to export into the mm directory of the kernel

otherwise you have to disable cifs_writepages and fall back to 4K writes.