freebsd-skq/sys/cam/cam_xpt_periph.h
Scott Long 5d01277f59 Add infrastructure to the ATA and SCSI transports that supports
using a driver-supplied sbuf for printing device discovery
announcements. This helps ensure that messages to the console
will be properly serialized (through sbuf_putbuf) and not be
truncated and interleaved with other messages. The
infrastructure mirrors the existing xpt_announce_periph()
entry point and is opt-in for now. No content or formatting
changes are visible to the operator other than the new coherency.

While here, eliminate the stack usage of the temporary
announcement buffer in some of the drivers. It's moved to the
softc for now, but future work will eliminate it entirely by
making the code flow more linear. Future work will also address
locking so that the sbufs can be dynamically sized.

The scsi_da, scs_cd, scsi_ses, and ata_da drivers are converted
at this point, other drivers can be converted at a later date.
A tunable+sysctl, kern.cam.announce_nosbuf, exists for testing
purposes but will be removed later.

TODO:
Eliminate all of the code duplication and temporary buffers.  The
old printf-based methods will be retired, and xpt_announce_periph()
will just be a wrapper that uses a dynamically sized sbuf.  This
requires that the register and deregister paths be made malloc-safe,
which they aren't currently.

Sponsored by:	Netflix
2017-04-19 15:04:52 +00:00

61 lines
2.5 KiB
C

/*-
* Data structures and definitions for dealing with the
* Common Access Method Transport (xpt) layer from peripheral
* drivers.
*
* Copyright (c) 1997 Justin T. Gibbs.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _CAM_CAM_XPT_PERIPH_H
#define _CAM_CAM_XPT_PERIPH_H 1
#include <cam/cam_queue.h>
#include <cam/cam_xpt.h>
/* Functions accessed by the peripheral drivers */
#ifdef _KERNEL
void xpt_polled_action(union ccb *ccb);
void xpt_release_ccb(union ccb *released_ccb);
void xpt_schedule(struct cam_periph *perph, u_int32_t new_priority);
int32_t xpt_add_periph(struct cam_periph *periph);
void xpt_remove_periph(struct cam_periph *periph);
void xpt_announce_periph(struct cam_periph *periph,
char *announce_string);
void xpt_announce_periph_sbuf(struct cam_periph *periph,
struct sbuf *sb,
char *announce_string);
void xpt_announce_quirks(struct cam_periph *periph,
int quirks, char *bit_string);
void xpt_announce_quirks_sbuf(struct cam_periph *periph,
struct sbuf *sb,
int quirks, char *bit_string);
void xpt_denounce_periph(struct cam_periph *periph);
void xpt_denounce_periph_sbuf(struct cam_periph *periph, struct sbuf *sb);
#endif
#endif /* _CAM_CAM_XPT_PERIPH_H */