Re: io_pgetevents & aio fsync V2
From: Christoph Hellwig <hch@lst.de>
Date: 2018-04-06 06:27:02
Also in:
linux-fsdevel, lkml
On Fri, Apr 06, 2018 at 04:16:30AM +0100, Al Viro wrote:
BTW, this is only tangentially related, but... does *anything* call io_submit() for huge amounts of iocb? Check in do_io_submit() is insane - "no more than MAX_LONG total of _pointers_". Compat variant goes for "no more than a page worth of pointers" and there's a hard limit in ioctx_alloc() - we can't ever get more than 8M slots in ring buffer...
Logical upper bound for io_submit is nr_events passed to io_setup(), which is bound by aio_max_nr. Except that we never actually check against nr_events (or max_reqs as it is known in kernel) in io_submit. Sigh.. -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: <a href=mailto:"aart@kvack.org">aart@kvack.org</a>