Re: sendfile64() on x86_64 breaks at 2gb (MAX_NON_LFS limit)

[Jakub Jelinek]

On Thu, Sep 23, 2004 at 12:09:29PM -0500, Mr. Berkley Shands wrote:
> for the opteron, the value of MAX_NON_LFS (include/linux/fs.h) is fixed 
> at (1UL<<31 -1).
> Since ALL 64 bit boxes force O_LARGEFILE on, shouldn't this value be 
> (1UL<<63 -1) so that
> sendfile64() will proceed beyond the 2gb limit?
> under 2.6.6, sendfile64() has no __NR_sendfile64 entry in asm*/unistd.h 
> (same for 2.6.9-rc2)
> so the syscall sendfile64() maps to sendfile(), which has MAX_NON_LFS 
> hard coded in fs/read_write.c
> as its limit, rather than 0ULL as in sendfile64().
> 
> So the fix is to make the correct entry for sendfile64 in unistd.h (note 
> that this hoses /usr/include/.../syscalls.h :-)
> and update fs.h as folows:

No.  You want the MAX_NON_LFS limit for 32-bit programs that call sendfile()
(as opposed to sendfile64()) on 64-bit arches.

The correct fix which is in the kernel for a few months is:
http://linux.bkbits.net:8080/linux-2.5/diffs/include/asm-x86_64/unistd.h@xxxx

	Jakub
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/