MFC r330627:

g_bio(9): fix a documentation oversight from r163870

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Per Ravi Pokala's suggestion, rewrite the g_reset_bio description to
be clearer. It also describes it with more nuance. Add missing MLINKS
noticed by trasz@. Bump the date.

Bump date. Forgotten in r299312.

Document g_reset_bio(). This is long overdue. g_reset_bio will reset
the bio to a pristine state should you wish to re-use it for another
I/O without freeing it. In the bast, a simple bzero was done to do
this, but that may not be sufficient in the future when the bio may
contain state that's not part of the documented API. Besides, it makes
the code clearer as to the intent...

Noticed by: smh@

Fix a comment typo in the code example.

PR: 203497
Submitted by: chadf@triularity.org
MFC after: 1 week

use .Mt to mark up email addresses consistently (part6)

PR: 191174
Submitted by: Franco Fichtner <franco at lastsummer.de>

Add missing 'bp', since it should be passed as g_print_bio() argument.

Oked by: pjd

Better English.

Submitted by: ru

- Document two new function g_alloc_bio() and g_duplicate_bio().
- Bump modification date.
- Update copyright years.

Document BIO_FLUSH request.

- Add two fields to bio structure: 'bio_cflags' which can be used by
consumer and 'bio_pflags' which can be used by provider.
- Remove BIO_FLAG1 and BIO_FLAG2 flags. From now on new fields should be
used for internal flags.
- Update g_bio(9) manual page.
- Update some comments.
- Update GEOM_MIRROR, which was the only one using BIO_FLAGs.

Idea from: phk
Reviewed by: phk

Tiny markup fixes.

Sort SEE ALSO references (in dictionary order, ignoring case).

Spelling fixes.

These hyphens don't need to be escaped.

Pointed out by: pjd@

Update several GEOM related manual pages:

*) Fix spelling errors.
*) Better english.
*) Re-phrasing.

Not Reviewed by: pjd (one week timeout)
Approved by: grog (mentor)

Add reference to the g_access(9) manual page.

Document g_print_bio() function.

Approved by: scottl (mentor)

Added first part of GEOM kernel API manuals pages.
Documented function and macros are:
- DECLARE_GEOM_CLASS(),
- g_attach(),
- g_detach(),
- g_new_bio(),
- g_clone_bio(),
- g_destroy_bio(),
- g_new_consumer(),
- g_destroy_consumer(),
- g_read_data(),
- g_write_data(),
- g_post_event(),
- g_waitfor_event(),
- g_cancel_event(),
- g_new_geomf(),
- g_destroy_geom(),
- g_new_providerf(),
- g_destroy_provider(),
- g_error_provider(),
- g_provider_by_name(),
- g_wither_geom().
and more to come.

I want to thanks following people for help with those documents:
Slawek Zak <zaks@prioris.mini.pw.edu.pl>
Simon L. Nielsen <simon@FreeBSD.org>
Pieter de Boer <g.p.de.boer@st.hanze.nl>
and of course
Poul-Henning Kamp <phk@FreeBSD.org>

Reviewed by: phk, scottl
Approved by: phk, scottl (mentor)