Re: sendfile -EOVERFLOW on AMD64

[Jakub Jelinek <jakub@redhat.com>]

On Wed, May 19, 2004 at 12:38:56PM +0200, Jan Kasprzak wrote:
> Andi Kleen wrote:
> : Jan Kasprzak <kas@informatics.muni.cz> writes:
> : >
> : > The image (FC2-i386-DVD.iso) has 4370640896 bytes. The FTP server is native
> : > x86_64 binary, not a 32-bit one.
> : 
> : sys_sendfile limits itself dumbly to 2GB even on 64bit architectures.
> : This patch should fix it on x86-64, although other 64bit ports may 
> : need a similar patch. Just removing the limit in read_write 
> : is not easy, because it would need fixes in all the 32bit emulation
> : layers.
> : 
> 	It partly helped, thanks. But there is still one more problem
> - it looks like sendfile() returns 32-bit value instead of 64-bit.
> My debug info looks like this:
> 
> sendfile(offset=0, count=4370640896)
>     = -767073160, offset=3527894136
> 
> where I do
> 
> 	long val = sendfile(...); printf(...%ld..., val);

What filesystem you're using?
For XFS I'd expect this:
STATIC ssize_t
linvfs_sendfile(
        struct file             *filp,
        loff_t                  *ppos,
        size_t                  count,
        read_actor_t            actor,
        void                    *target)
{
        vnode_t                 *vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
        int                     error;

        VOP_SENDFILE(vp, filp, ppos, 0, count, actor, target, NULL, error);
        return error;
}

(note error is int, not ssize_t), but I don't see anything obvious
for other filesystems.

	Jakub