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- /*-
- * CAM IO Scheduler Interface
- *
- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
- *
- * Copyright (c) 2015 Netflix, Inc.
- *
- * 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_IOSCHED_H
- #define _CAM_CAM_IOSCHED_H
- /* No user-serviceable parts in here. */
- #ifdef _KERNEL
- /* Forward declare all structs to keep interface thin */
- struct cam_iosched_softc;
- struct sysctl_ctx_list;
- struct sysctl_oid;
- union ccb;
- struct bio;
- /*
- * For 64-bit platforms, we know that uintptr_t is the same size as sbintime_t
- * so we can store values in it. For 32-bit systems, however, uintptr_t is only
- * 32-bits, so it won't fit. For those systems, store 24 bits of fraction and 8
- * bits of seconds. This allows us to measure an interval of up to ~256s, which
- * is ~200x what our current uses require. Provide some convenience functions to
- * get the time, subtract two times and convert back to sbintime_t in a safe way
- * that can be centralized.
- */
- #ifdef __LP64__
- #define CAM_IOSCHED_TIME_SHIFT 0
- #else
- #define CAM_IOSCHED_TIME_SHIFT 8
- #endif
- static inline uintptr_t
- cam_iosched_now(void)
- {
- /* Cast here is to avoid right shifting a signed value */
- return (uintptr_t)((uint64_t)sbinuptime() >> CAM_IOSCHED_TIME_SHIFT);
- }
- static inline uintptr_t
- cam_iosched_delta_t(uintptr_t then)
- {
- /* Since the types are identical, wrapping works correctly */
- return (cam_iosched_now() - then);
- }
- static inline sbintime_t
- cam_iosched_sbintime_t(uintptr_t delta)
- {
- /* Cast here is to widen the type so the left shift doesn't lose precision */
- return (sbintime_t)((uint64_t)delta << CAM_IOSCHED_TIME_SHIFT);
- }
- typedef void (*cam_iosched_latfcn_t)(void *, sbintime_t, struct bio *);
- int cam_iosched_init(struct cam_iosched_softc **, struct cam_periph *periph);
- void cam_iosched_fini(struct cam_iosched_softc *);
- void cam_iosched_sysctl_init(struct cam_iosched_softc *, struct sysctl_ctx_list *, struct sysctl_oid *);
- struct bio *cam_iosched_next_trim(struct cam_iosched_softc *isc);
- struct bio *cam_iosched_get_trim(struct cam_iosched_softc *isc);
- struct bio *cam_iosched_next_bio(struct cam_iosched_softc *isc);
- void cam_iosched_queue_work(struct cam_iosched_softc *isc, struct bio *bp);
- void cam_iosched_flush(struct cam_iosched_softc *isc, struct devstat *stp, int err);
- void cam_iosched_schedule(struct cam_iosched_softc *isc, struct cam_periph *periph);
- void cam_iosched_finish_trim(struct cam_iosched_softc *isc);
- void cam_iosched_submit_trim(struct cam_iosched_softc *isc);
- void cam_iosched_put_back_trim(struct cam_iosched_softc *isc, struct bio *bp);
- void cam_iosched_set_sort_queue(struct cam_iosched_softc *isc, int val);
- int cam_iosched_has_work_flags(struct cam_iosched_softc *isc, uint32_t flags);
- void cam_iosched_set_work_flags(struct cam_iosched_softc *isc, uint32_t flags);
- void cam_iosched_clr_work_flags(struct cam_iosched_softc *isc, uint32_t flags);
- void cam_iosched_trim_done(struct cam_iosched_softc *isc);
- int cam_iosched_bio_complete(struct cam_iosched_softc *isc, struct bio *bp, union ccb *done_ccb);
- void cam_iosched_set_latfcn(struct cam_iosched_softc *isc, cam_iosched_latfcn_t, void *);
- void cam_iosched_set_trim_goal(struct cam_iosched_softc *isc, int goal);
- void cam_iosched_set_trim_ticks(struct cam_iosched_softc *isc, int ticks);
- #endif
- #endif
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