The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch up to that fact and revert to their recommended match of BSD-2-Clause. Discussed with: pfg MFC After: 3 days Sponsored by: Netflix
145 lines
5.6 KiB
C
145 lines
5.6 KiB
C
/*-
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* SPDX-License-Identifier: BSD-2-Clause
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*
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* Copyright (c) 2022 Marshall Kirk McKusick <mckusick@mckusick.com>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef _G_UNION_H_
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#define _G_UNION_H_
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#define G_UNION_CLASS_NAME "UNION"
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#define G_UNION_VERSION 1
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#define G_UNION_SUFFIX ".union"
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/*
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* Special flag to instruct gunion to passthrough the underlying provider's
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* physical path
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*/
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#define G_UNION_PHYSPATH_PASSTHROUGH "\255"
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#ifdef _KERNEL
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#define G_UNION_DEBUG(lvl, ...) \
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_GEOM_DEBUG("GEOM_UNION", g_union_debug, (lvl), NULL, __VA_ARGS__)
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#define G_UNION_LOGREQLVL(lvl, bp, ...) \
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_GEOM_DEBUG("GEOM_UNION", g_union_debug, (lvl), (bp), __VA_ARGS__)
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#define G_UNION_LOGREQ(bp, ...) G_UNION_LOGREQLVL(3, (bp), __VA_ARGS__)
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TAILQ_HEAD(wiplist, g_union_wip);
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/*
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* State maintained by each instance of a UNION GEOM.
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*/
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struct g_union_softc {
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struct rwlock sc_rwlock; /* writemap lock */
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uint64_t **sc_writemap_root; /* root of write map */
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uint64_t *sc_leafused; /* 1 => leaf has allocation */
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uint64_t sc_map_size; /* size of write map */
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long sc_root_size; /* entries in root node */
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long sc_leaf_size; /* entries in leaf node */
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long sc_bits_per_leaf; /* bits per leaf node entry */
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long sc_writemap_memory; /* memory used by writemap */
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off_t sc_offset; /* starting offset in lower */
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off_t sc_size; /* size of union geom */
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off_t sc_sectorsize; /* sector size of geom */
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struct g_consumer *sc_uppercp; /* upper-level provider */
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struct g_consumer *sc_lowercp; /* lower-level provider */
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struct wiplist sc_wiplist; /* I/O work-in-progress list */
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long sc_flags; /* see flags below */
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long sc_reads; /* number of reads done */
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long sc_wrotebytes; /* number of bytes written */
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long sc_writes; /* number of writes done */
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long sc_readbytes; /* number of bytes read */
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long sc_deletes; /* number of deletes done */
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long sc_getattrs; /* number of getattrs done */
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long sc_flushes; /* number of flushes done */
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long sc_cmd0s; /* number of cmd0's done */
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long sc_cmd1s; /* number of cmd1's done */
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long sc_cmd2s; /* number of cmd2's done */
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long sc_speedups; /* number of speedups done */
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long sc_readcurrentread; /* reads current with read */
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long sc_readblockwrite; /* writes blocked by read */
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long sc_writeblockread; /* reads blocked by write */
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long sc_writeblockwrite; /* writes blocked by write */
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};
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/*
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* Structure to track work-in-progress I/O operations.
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*
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* Used to prevent overlapping I/O operations from running concurrently.
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* Created for each I/O operation.
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*
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* In usual case of no overlap it is linked to sc_wiplist and started.
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* If found to overlap an I/O on sc_wiplist, it is not started and is
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* linked to wip_waiting list of the I/O that it overlaps. When an I/O
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* completes, it restarts all the I/O operations on its wip_waiting list.
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*/
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struct g_union_wip {
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struct wiplist wip_waiting; /* list of I/Os waiting on me */
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TAILQ_ENTRY(g_union_wip) wip_next; /* pending or active I/O list */
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struct bio *wip_bp; /* bio for this I/O */
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struct g_union_softc *wip_sc; /* g_union's softc */
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off_t wip_start; /* starting offset of I/O */
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off_t wip_end; /* ending offset of I/O */
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long wip_numios; /* BIO_READs in progress */
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long wip_error; /* merged I/O errors */
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};
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/*
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* UNION flags
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*/
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#define DOING_COMMIT 0x00000001 /* a commit command is in progress */
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#define DOING_COMMIT_BITNUM 0 /* a commit command is in progress */
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#define BITS_PER_ENTRY (sizeof(uint64_t) * NBBY)
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#define G_RLOCK(sc) rw_rlock(&(sc)->sc_rwlock)
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#define G_RUNLOCK(sc) rw_runlock(&(sc)->sc_rwlock)
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#define G_WLOCK(sc) rw_wlock(&(sc)->sc_rwlock)
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#define G_WUNLOCK(sc) rw_wunlock(&(sc)->sc_rwlock)
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#define G_WLOCKOWNED(sc) rw_assert(&(sc)->sc_rwlock, RA_WLOCKED)
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/*
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* The writelock is held while a commit operation is in progress.
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* While held union device may not be used or in use.
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* Returns == 0 if lock was successfully obtained.
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*/
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static inline int
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g_union_get_writelock(struct g_union_softc *sc)
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{
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return (atomic_testandset_long(&sc->sc_flags, DOING_COMMIT_BITNUM));
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}
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static inline void
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g_union_rel_writelock(struct g_union_softc *sc)
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{
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long ret __diagused;
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ret = atomic_testandclear_long(&sc->sc_flags, DOING_COMMIT_BITNUM);
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KASSERT(ret != 0, ("UNION GEOM releasing unheld lock"));
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}
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#endif /* _KERNEL */
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#endif /* _G_UNION_H_ */
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