redo diff as markj suggested.

Yea, I didn't know what the problem having invalid pages on the paging queues would be either.

The intention is that ffs_subr.c should only contain functions that are shared by the ufs kernel module and the libufs userland library. At some point the geom_label kernel module started using ffs_subr.c too even though that is cross-module direct reference, which is problematic when not all of the modules are statically included in the base kernel. Now that I moved the functions which are only needed by the ufs kernel module elsewhere, geom_label's instance of ffs_subr.c no longer references M_UFSMNT, so this change is not necessary.

Gleb asked me to commit this so that git blame will still blame me. :-)
The diff looks fine to me, adding kirk as a reviewer also.

really remove putpages wrapper this time.

update to address review comments.

update diff to 360823

Are there any more comments on this diff?

generally, having the function that submits an async request return a pointer a request structure that is freed when the request completes is a bad idea, since the caller will have handle the request structure having already been freed, and thus having a pointer to it isn't useful. as you guys discussed, using the normal timeout path for polled commands (and fixing the normal timeout path to not be racy) would be good. a fun corner case will be when the use of the abort command in the timeout path itself times out.

update with changes suggested by kib and imp.

There's no central place in the ufs code to add an assertion about not creating buffers on odevvp. What I could do is define a new BO_NOBUFS flag for bufobj bo_flag, set that flag on odevvp in ffs_mountfs() and clear the flag in ffs_unmount(), and then in buf_vlist_add() assert that (bo->bo_flag & BO_NOBUFS) == 0. Is that what you had in mind?

minor nit: the returned "resid" value is unused. otherwise looks good.

looks good.

looks good.

I'll try to address all the points that everyone has made so far here.