Theodore, I might be missing understanding something, but... I already omitted read2 and write2 which can be implemented in userspace by libc (as you pointed out). In the case of readv vs. preadv there's an extra positional argument (file offset) and preadv version doesn't change the file location. I didn't want to overload the meaning of preadv2 to take a special negative offset value that uses the current file position but also changes the file position. As a counter point to my view point, Christop also brought the same thing as you did. - Milosz On Wed, Sep 17, 2014 at 11:43 AM, Theodore Ts'o <tytso@xxxxxxx> wrote: > On Mon, Sep 15, 2014 at 04:20:37PM -0400, Milosz Tanski wrote: >> New syscalls with an extra flag argument. For now all flags except for 0 are >> not supported. > > This may fall in the category of bike-shedding, and so I apologize in > advance, but I wonder if we really need readv2 and writev2 as new > syscalls. What if we just added preadv2 and pwritev2, and implemented > readv2 and writev2 as libc wrappers where which had the vector > allocated as an automatic stack variable? Is the extra user memory > access really going to be that noticeable? > > Cheers, > > - Ted -- Milosz Tanski CTO 16 East 34th Street, 15th floor New York, NY 10016 p: 646-253-9055 e: milosz@xxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
