Re: Re: Access content of file via inodes

["Kathy KN (HK)" <kathy.kn@xxxxxxxxx>]

On Apr 7, 2005 3:40 AM, Martin Jambor <jamborm@xxxxxxxxx> wrote:
> On Apr 6, 2005 3:49 AM, Kathy KN (HK) <kathy.kn@xxxxxxxxx> wrote:
> > Seems like it is not going to be easy. I don't have much parameters
> > required to be able to perform similarly to what generic_file_*[1] did,
> > particularly count, ppos, etc.
> >
> > [1] i.e.
> > 2201 ssize_t generic_file_write(struct file *file, const char __user *buf,
> > 2202                            size_t count, loff_t *ppos)
> 
> I was not suggesting you call the method directly as it copies data to
> userspace, I just wanted to show you code that may inspire you. The
> function uses pos to find the appropriate page and writes data there.
> 
> Anyway, if marking buffers dirty works for you, go for it. However,
> what are you going to do if the part of the file you are intereste in
> is not cached in memory yet?

The marking buffers dirty and call bdflush work. I have not tried with
larger files. I suspect that I might just encounter problems like you
mentioned (i.e. what if part of the file is not cached in memory).
Thanks for the inspiration tips.

Kathy

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