From 03c6040bee6c87a9413b7da41d9f580f79a8ab62 Mon Sep 17 00:00:00 2001 From: George Wilson Date: Fri, 10 May 2013 12:47:54 -0700 Subject: Illumos #3236 3236 zio nop-write Reviewed by: Matt Ahrens Reviewed by: Adam Leventhal Reviewed by: Christopher Siden Approved by: Garrett D'Amore References: illumos/illumos-gate@80901aea8e78a2c20751f61f01bebd1d5b5c2ba5 https://www.illumos.org/issues/3236 Porting Notes 1. This patch is being merged dispite an increased instance of https://www.illumos.org/issues/3113 being triggered by ztest. Ported-by: Brian Behlendorf Issue #1489 --- module/zfs/zio.c | 105 +++++++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 95 insertions(+), 10 deletions(-) (limited to 'module/zfs/zio.c') diff --git a/module/zfs/zio.c b/module/zfs/zio.c index a24f2bef3..1f803a44b 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -723,9 +723,7 @@ zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, DMU_OT_IS_VALID(zp->zp_type) && zp->zp_level < 32 && zp->zp_copies > 0 && - zp->zp_copies <= spa_max_replication(spa) && - zp->zp_dedup <= 1 && - zp->zp_dedup_verify <= 1); + zp->zp_copies <= spa_max_replication(spa)); zio = zio_create(pio, spa, txg, bp, data, size, done, private, ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb, @@ -753,13 +751,20 @@ zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data, } void -zio_write_override(zio_t *zio, blkptr_t *bp, int copies) +zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite) { ASSERT(zio->io_type == ZIO_TYPE_WRITE); ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); ASSERT(zio->io_stage == ZIO_STAGE_OPEN); ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa)); + /* + * We must reset the io_prop to match the values that existed + * when the bp was first written by dmu_sync() keeping in mind + * that nopwrite and dedup are mutually exclusive. + */ + zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup; + zio->io_prop.zp_nopwrite = nopwrite; zio->io_prop.zp_copies = copies; zio->io_bp_override = bp; } @@ -1051,6 +1056,19 @@ zio_write_bp_init(zio_t *zio) *bp = *zio->io_bp_override; zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; + /* + * If we've been overridden and nopwrite is set then + * set the flag accordingly to indicate that a nopwrite + * has already occurred. + */ + if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) { + ASSERT(!zp->zp_dedup); + zio->io_flags |= ZIO_FLAG_NOPWRITE; + return (ZIO_PIPELINE_CONTINUE); + } + + ASSERT(!zp->zp_nopwrite); + if (BP_IS_HOLE(bp) || !zp->zp_dedup) return (ZIO_PIPELINE_CONTINUE); @@ -1138,6 +1156,11 @@ zio_write_bp_init(zio_t *zio) ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE; } + if (zp->zp_nopwrite) { + ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); + ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); + zio->io_pipeline |= ZIO_STAGE_NOP_WRITE; + } } return (ZIO_PIPELINE_CONTINUE); @@ -1404,6 +1427,7 @@ zio_reexecute(zio_t *pio) pio->io_stage = pio->io_orig_stage; pio->io_pipeline = pio->io_orig_pipeline; pio->io_reexecute = 0; + pio->io_flags |= ZIO_FLAG_REEXECUTED; pio->io_error = 0; for (w = 0; w < ZIO_WAIT_TYPES; w++) pio->io_state[w] = 0; @@ -1887,8 +1911,9 @@ zio_write_gang_block(zio_t *pio) zp.zp_type = DMU_OT_NONE; zp.zp_level = 0; zp.zp_copies = gio->io_prop.zp_copies; - zp.zp_dedup = 0; - zp.zp_dedup_verify = 0; + zp.zp_dedup = B_FALSE; + zp.zp_dedup_verify = B_FALSE; + zp.zp_nopwrite = B_FALSE; zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g], (char *)pio->io_data + (pio->io_size - resid), lsize, &zp, @@ -1912,6 +1937,62 @@ zio_write_gang_block(zio_t *pio) return (ZIO_PIPELINE_CONTINUE); } +/* + * The zio_nop_write stage in the pipeline determines if allocating + * a new bp is necessary. By leveraging a cryptographically secure checksum, + * such as SHA256, we can compare the checksums of the new data and the old + * to determine if allocating a new block is required. The nopwrite + * feature can handle writes in either syncing or open context (i.e. zil + * writes) and as a result is mutually exclusive with dedup. + */ +static int +zio_nop_write(zio_t *zio) +{ + blkptr_t *bp = zio->io_bp; + blkptr_t *bp_orig = &zio->io_bp_orig; + zio_prop_t *zp = &zio->io_prop; + + ASSERT(BP_GET_LEVEL(bp) == 0); + ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); + ASSERT(zp->zp_nopwrite); + ASSERT(!zp->zp_dedup); + ASSERT(zio->io_bp_override == NULL); + ASSERT(IO_IS_ALLOCATING(zio)); + + /* + * Check to see if the original bp and the new bp have matching + * characteristics (i.e. same checksum, compression algorithms, etc). + * If they don't then just continue with the pipeline which will + * allocate a new bp. + */ + if (BP_IS_HOLE(bp_orig) || + !zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_dedup || + BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) || + BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) || + BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) || + zp->zp_copies != BP_GET_NDVAS(bp_orig)) + return (ZIO_PIPELINE_CONTINUE); + + /* + * If the checksums match then reset the pipeline so that we + * avoid allocating a new bp and issuing any I/O. + */ + if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) { + ASSERT(zio_checksum_table[zp->zp_checksum].ci_dedup); + ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig)); + ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig)); + ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF); + ASSERT(bcmp(&bp->blk_prop, &bp_orig->blk_prop, + sizeof (uint64_t)) == 0); + + *bp = *bp_orig; + zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; + zio->io_flags |= ZIO_FLAG_NOPWRITE; + } + + return (ZIO_PIPELINE_CONTINUE); +} + /* * ========================================================================== * Dedup @@ -2186,7 +2267,7 @@ zio_ddt_write(zio_t *zio) zio->io_stage = ZIO_STAGE_OPEN; BP_ZERO(bp); } else { - zp->zp_dedup = 0; + zp->zp_dedup = B_FALSE; } zio->io_pipeline = ZIO_WRITE_PIPELINE; ddt_exit(ddt); @@ -2815,7 +2896,8 @@ zio_ready(zio_t *zio) if (zio->io_ready) { ASSERT(IO_IS_ALLOCATING(zio)); - ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp)); + ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp) || + (zio->io_flags & ZIO_FLAG_NOPWRITE)); ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0); zio->io_ready(zio); @@ -2893,6 +2975,8 @@ zio_done(zio_t *zio) ASSERT(BP_COUNT_GANG(zio->io_bp) == 0 || (BP_COUNT_GANG(zio->io_bp) == BP_GET_NDVAS(zio->io_bp))); } + if (zio->io_flags & ZIO_FLAG_NOPWRITE) + VERIFY(BP_EQUAL(zio->io_bp, &zio->io_bp_orig)); } /* @@ -3015,7 +3099,7 @@ zio_done(zio_t *zio) if ((zio->io_error || zio->io_reexecute) && IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio && - !(zio->io_flags & ZIO_FLAG_IO_REWRITE)) + !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE))) zio_dva_unallocate(zio, zio->io_gang_tree, zio->io_bp); zio_gang_tree_free(&zio->io_gang_tree); @@ -3112,7 +3196,7 @@ zio_done(zio_t *zio) } if (zio->io_flags & ZIO_FLAG_FASTWRITE && zio->io_bp && - !BP_IS_HOLE(zio->io_bp)) { + !BP_IS_HOLE(zio->io_bp) && !(zio->io_flags & ZIO_FLAG_NOPWRITE)) { metaslab_fastwrite_unmark(zio->io_spa, zio->io_bp); } @@ -3159,6 +3243,7 @@ static zio_pipe_stage_t *zio_pipeline[] = { zio_issue_async, zio_write_bp_init, zio_checksum_generate, + zio_nop_write, zio_ddt_read_start, zio_ddt_read_done, zio_ddt_write, -- cgit v1.2.3