2551 lines
71 KiB
C
2551 lines
71 KiB
C
/*
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* CDDL HEADER START
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*
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* The contents of this file are subject to the terms of the
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* Common Development and Distribution License (the "License").
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* You may not use this file except in compliance with the License.
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*
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* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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* or http://www.opensolaris.org/os/licensing.
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* See the License for the specific language governing permissions
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* and limitations under the License.
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*
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* When distributing Covered Code, include this CDDL HEADER in each
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* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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* If applicable, add the following below this CDDL HEADER, with the
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* fields enclosed by brackets "[]" replaced with your own identifying
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* information: Portions Copyright [yyyy] [name of copyright owner]
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*
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* CDDL HEADER END
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*/
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/*
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* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 2012, 2020 by Delphix. All rights reserved.
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* Copyright (c) 2016 Gvozden Nešković. All rights reserved.
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*/
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#include <sys/zfs_context.h>
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#include <sys/spa.h>
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#include <sys/vdev_impl.h>
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#include <sys/zio.h>
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#include <sys/zio_checksum.h>
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#include <sys/abd.h>
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#include <sys/fs/zfs.h>
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#include <sys/fm/fs/zfs.h>
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#include <sys/vdev_raidz.h>
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#include <sys/vdev_raidz_impl.h>
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#include <sys/vdev_draid.h>
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#ifdef ZFS_DEBUG
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#include <sys/vdev.h> /* For vdev_xlate() in vdev_raidz_io_verify() */
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#endif
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/*
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* Virtual device vector for RAID-Z.
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*
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* This vdev supports single, double, and triple parity. For single parity,
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* we use a simple XOR of all the data columns. For double or triple parity,
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* we use a special case of Reed-Solomon coding. This extends the
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* technique described in "The mathematics of RAID-6" by H. Peter Anvin by
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* drawing on the system described in "A Tutorial on Reed-Solomon Coding for
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* Fault-Tolerance in RAID-like Systems" by James S. Plank on which the
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* former is also based. The latter is designed to provide higher performance
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* for writes.
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*
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* Note that the Plank paper claimed to support arbitrary N+M, but was then
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* amended six years later identifying a critical flaw that invalidates its
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* claims. Nevertheless, the technique can be adapted to work for up to
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* triple parity. For additional parity, the amendment "Note: Correction to
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* the 1997 Tutorial on Reed-Solomon Coding" by James S. Plank and Ying Ding
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* is viable, but the additional complexity means that write performance will
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* suffer.
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*
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* All of the methods above operate on a Galois field, defined over the
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* integers mod 2^N. In our case we choose N=8 for GF(8) so that all elements
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* can be expressed with a single byte. Briefly, the operations on the
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* field are defined as follows:
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*
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* o addition (+) is represented by a bitwise XOR
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* o subtraction (-) is therefore identical to addition: A + B = A - B
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* o multiplication of A by 2 is defined by the following bitwise expression:
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*
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* (A * 2)_7 = A_6
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* (A * 2)_6 = A_5
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* (A * 2)_5 = A_4
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* (A * 2)_4 = A_3 + A_7
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* (A * 2)_3 = A_2 + A_7
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* (A * 2)_2 = A_1 + A_7
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* (A * 2)_1 = A_0
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* (A * 2)_0 = A_7
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*
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* In C, multiplying by 2 is therefore ((a << 1) ^ ((a & 0x80) ? 0x1d : 0)).
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* As an aside, this multiplication is derived from the error correcting
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* primitive polynomial x^8 + x^4 + x^3 + x^2 + 1.
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*
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* Observe that any number in the field (except for 0) can be expressed as a
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* power of 2 -- a generator for the field. We store a table of the powers of
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* 2 and logs base 2 for quick look ups, and exploit the fact that A * B can
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* be rewritten as 2^(log_2(A) + log_2(B)) (where '+' is normal addition rather
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* than field addition). The inverse of a field element A (A^-1) is therefore
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* A ^ (255 - 1) = A^254.
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*
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* The up-to-three parity columns, P, Q, R over several data columns,
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* D_0, ... D_n-1, can be expressed by field operations:
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*
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* P = D_0 + D_1 + ... + D_n-2 + D_n-1
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* Q = 2^n-1 * D_0 + 2^n-2 * D_1 + ... + 2^1 * D_n-2 + 2^0 * D_n-1
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* = ((...((D_0) * 2 + D_1) * 2 + ...) * 2 + D_n-2) * 2 + D_n-1
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* R = 4^n-1 * D_0 + 4^n-2 * D_1 + ... + 4^1 * D_n-2 + 4^0 * D_n-1
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* = ((...((D_0) * 4 + D_1) * 4 + ...) * 4 + D_n-2) * 4 + D_n-1
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*
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* We chose 1, 2, and 4 as our generators because 1 corresponds to the trivial
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* XOR operation, and 2 and 4 can be computed quickly and generate linearly-
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* independent coefficients. (There are no additional coefficients that have
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* this property which is why the uncorrected Plank method breaks down.)
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*
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* See the reconstruction code below for how P, Q and R can used individually
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* or in concert to recover missing data columns.
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*/
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#define VDEV_RAIDZ_P 0
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#define VDEV_RAIDZ_Q 1
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#define VDEV_RAIDZ_R 2
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#define VDEV_RAIDZ_MUL_2(x) (((x) << 1) ^ (((x) & 0x80) ? 0x1d : 0))
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#define VDEV_RAIDZ_MUL_4(x) (VDEV_RAIDZ_MUL_2(VDEV_RAIDZ_MUL_2(x)))
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/*
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* We provide a mechanism to perform the field multiplication operation on a
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* 64-bit value all at once rather than a byte at a time. This works by
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* creating a mask from the top bit in each byte and using that to
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* conditionally apply the XOR of 0x1d.
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*/
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#define VDEV_RAIDZ_64MUL_2(x, mask) \
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{ \
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(mask) = (x) & 0x8080808080808080ULL; \
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(mask) = ((mask) << 1) - ((mask) >> 7); \
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(x) = (((x) << 1) & 0xfefefefefefefefeULL) ^ \
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((mask) & 0x1d1d1d1d1d1d1d1dULL); \
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}
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#define VDEV_RAIDZ_64MUL_4(x, mask) \
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{ \
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VDEV_RAIDZ_64MUL_2((x), mask); \
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VDEV_RAIDZ_64MUL_2((x), mask); \
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}
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static void
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vdev_raidz_row_free(raidz_row_t *rr)
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{
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for (int c = 0; c < rr->rr_cols; c++) {
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raidz_col_t *rc = &rr->rr_col[c];
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if (rc->rc_size != 0)
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abd_free(rc->rc_abd);
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if (rc->rc_orig_data != NULL)
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abd_free(rc->rc_orig_data);
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}
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if (rr->rr_abd_empty != NULL)
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abd_free(rr->rr_abd_empty);
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kmem_free(rr, offsetof(raidz_row_t, rr_col[rr->rr_scols]));
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}
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void
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vdev_raidz_map_free(raidz_map_t *rm)
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{
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for (int i = 0; i < rm->rm_nrows; i++)
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vdev_raidz_row_free(rm->rm_row[i]);
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kmem_free(rm, offsetof(raidz_map_t, rm_row[rm->rm_nrows]));
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}
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static void
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vdev_raidz_map_free_vsd(zio_t *zio)
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{
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raidz_map_t *rm = zio->io_vsd;
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vdev_raidz_map_free(rm);
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}
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const zio_vsd_ops_t vdev_raidz_vsd_ops = {
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.vsd_free = vdev_raidz_map_free_vsd,
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};
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/*
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* Divides the IO evenly across all child vdevs; usually, dcols is
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* the number of children in the target vdev.
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*
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* Avoid inlining the function to keep vdev_raidz_io_start(), which
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* is this functions only caller, as small as possible on the stack.
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*/
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noinline raidz_map_t *
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vdev_raidz_map_alloc(zio_t *zio, uint64_t ashift, uint64_t dcols,
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uint64_t nparity)
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{
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raidz_row_t *rr;
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/* The starting RAIDZ (parent) vdev sector of the block. */
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uint64_t b = zio->io_offset >> ashift;
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/* The zio's size in units of the vdev's minimum sector size. */
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uint64_t s = zio->io_size >> ashift;
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/* The first column for this stripe. */
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uint64_t f = b % dcols;
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/* The starting byte offset on each child vdev. */
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uint64_t o = (b / dcols) << ashift;
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uint64_t q, r, c, bc, col, acols, scols, coff, devidx, asize, tot;
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raidz_map_t *rm =
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kmem_zalloc(offsetof(raidz_map_t, rm_row[1]), KM_SLEEP);
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rm->rm_nrows = 1;
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/*
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* "Quotient": The number of data sectors for this stripe on all but
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* the "big column" child vdevs that also contain "remainder" data.
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*/
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q = s / (dcols - nparity);
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/*
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* "Remainder": The number of partial stripe data sectors in this I/O.
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* This will add a sector to some, but not all, child vdevs.
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*/
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r = s - q * (dcols - nparity);
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/* The number of "big columns" - those which contain remainder data. */
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bc = (r == 0 ? 0 : r + nparity);
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/*
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* The total number of data and parity sectors associated with
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* this I/O.
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*/
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tot = s + nparity * (q + (r == 0 ? 0 : 1));
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/*
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* acols: The columns that will be accessed.
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* scols: The columns that will be accessed or skipped.
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*/
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if (q == 0) {
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/* Our I/O request doesn't span all child vdevs. */
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acols = bc;
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scols = MIN(dcols, roundup(bc, nparity + 1));
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} else {
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acols = dcols;
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scols = dcols;
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}
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ASSERT3U(acols, <=, scols);
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rr = kmem_alloc(offsetof(raidz_row_t, rr_col[scols]), KM_SLEEP);
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rm->rm_row[0] = rr;
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rr->rr_cols = acols;
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rr->rr_scols = scols;
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rr->rr_bigcols = bc;
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rr->rr_missingdata = 0;
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rr->rr_missingparity = 0;
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rr->rr_firstdatacol = nparity;
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rr->rr_abd_empty = NULL;
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rr->rr_nempty = 0;
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#ifdef ZFS_DEBUG
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rr->rr_offset = zio->io_offset;
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rr->rr_size = zio->io_size;
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#endif
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asize = 0;
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for (c = 0; c < scols; c++) {
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raidz_col_t *rc = &rr->rr_col[c];
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col = f + c;
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coff = o;
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if (col >= dcols) {
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col -= dcols;
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coff += 1ULL << ashift;
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}
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rc->rc_devidx = col;
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rc->rc_offset = coff;
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rc->rc_abd = NULL;
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rc->rc_orig_data = NULL;
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rc->rc_error = 0;
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rc->rc_tried = 0;
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rc->rc_skipped = 0;
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rc->rc_force_repair = 0;
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rc->rc_allow_repair = 1;
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rc->rc_need_orig_restore = B_FALSE;
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if (c >= acols)
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rc->rc_size = 0;
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else if (c < bc)
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rc->rc_size = (q + 1) << ashift;
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else
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rc->rc_size = q << ashift;
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asize += rc->rc_size;
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}
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ASSERT3U(asize, ==, tot << ashift);
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rm->rm_nskip = roundup(tot, nparity + 1) - tot;
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rm->rm_skipstart = bc;
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for (c = 0; c < rr->rr_firstdatacol; c++)
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rr->rr_col[c].rc_abd =
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abd_alloc_linear(rr->rr_col[c].rc_size, B_FALSE);
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for (uint64_t off = 0; c < acols; c++) {
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raidz_col_t *rc = &rr->rr_col[c];
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rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct,
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zio->io_abd, off, rc->rc_size);
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off += rc->rc_size;
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}
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/*
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* If all data stored spans all columns, there's a danger that parity
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* will always be on the same device and, since parity isn't read
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* during normal operation, that device's I/O bandwidth won't be
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* used effectively. We therefore switch the parity every 1MB.
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*
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* ... at least that was, ostensibly, the theory. As a practical
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* matter unless we juggle the parity between all devices evenly, we
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* won't see any benefit. Further, occasional writes that aren't a
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* multiple of the LCM of the number of children and the minimum
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* stripe width are sufficient to avoid pessimal behavior.
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* Unfortunately, this decision created an implicit on-disk format
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* requirement that we need to support for all eternity, but only
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* for single-parity RAID-Z.
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*
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* If we intend to skip a sector in the zeroth column for padding
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* we must make sure to note this swap. We will never intend to
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* skip the first column since at least one data and one parity
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* column must appear in each row.
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*/
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ASSERT(rr->rr_cols >= 2);
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ASSERT(rr->rr_col[0].rc_size == rr->rr_col[1].rc_size);
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if (rr->rr_firstdatacol == 1 && (zio->io_offset & (1ULL << 20))) {
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devidx = rr->rr_col[0].rc_devidx;
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o = rr->rr_col[0].rc_offset;
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rr->rr_col[0].rc_devidx = rr->rr_col[1].rc_devidx;
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rr->rr_col[0].rc_offset = rr->rr_col[1].rc_offset;
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rr->rr_col[1].rc_devidx = devidx;
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rr->rr_col[1].rc_offset = o;
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if (rm->rm_skipstart == 0)
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rm->rm_skipstart = 1;
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}
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/* init RAIDZ parity ops */
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rm->rm_ops = vdev_raidz_math_get_ops();
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return (rm);
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}
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struct pqr_struct {
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uint64_t *p;
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uint64_t *q;
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uint64_t *r;
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};
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static int
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vdev_raidz_p_func(void *buf, size_t size, void *private)
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{
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struct pqr_struct *pqr = private;
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const uint64_t *src = buf;
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int i, cnt = size / sizeof (src[0]);
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ASSERT(pqr->p && !pqr->q && !pqr->r);
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for (i = 0; i < cnt; i++, src++, pqr->p++)
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*pqr->p ^= *src;
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return (0);
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}
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static int
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vdev_raidz_pq_func(void *buf, size_t size, void *private)
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{
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struct pqr_struct *pqr = private;
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const uint64_t *src = buf;
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uint64_t mask;
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int i, cnt = size / sizeof (src[0]);
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ASSERT(pqr->p && pqr->q && !pqr->r);
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for (i = 0; i < cnt; i++, src++, pqr->p++, pqr->q++) {
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*pqr->p ^= *src;
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VDEV_RAIDZ_64MUL_2(*pqr->q, mask);
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*pqr->q ^= *src;
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}
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return (0);
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}
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static int
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vdev_raidz_pqr_func(void *buf, size_t size, void *private)
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{
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struct pqr_struct *pqr = private;
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const uint64_t *src = buf;
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uint64_t mask;
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int i, cnt = size / sizeof (src[0]);
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ASSERT(pqr->p && pqr->q && pqr->r);
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for (i = 0; i < cnt; i++, src++, pqr->p++, pqr->q++, pqr->r++) {
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*pqr->p ^= *src;
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VDEV_RAIDZ_64MUL_2(*pqr->q, mask);
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*pqr->q ^= *src;
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VDEV_RAIDZ_64MUL_4(*pqr->r, mask);
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*pqr->r ^= *src;
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}
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return (0);
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}
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static void
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vdev_raidz_generate_parity_p(raidz_row_t *rr)
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{
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uint64_t *p = abd_to_buf(rr->rr_col[VDEV_RAIDZ_P].rc_abd);
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for (int c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
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abd_t *src = rr->rr_col[c].rc_abd;
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if (c == rr->rr_firstdatacol) {
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abd_copy_to_buf(p, src, rr->rr_col[c].rc_size);
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} else {
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struct pqr_struct pqr = { p, NULL, NULL };
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(void) abd_iterate_func(src, 0, rr->rr_col[c].rc_size,
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vdev_raidz_p_func, &pqr);
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}
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}
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}
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static void
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vdev_raidz_generate_parity_pq(raidz_row_t *rr)
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{
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uint64_t *p = abd_to_buf(rr->rr_col[VDEV_RAIDZ_P].rc_abd);
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uint64_t *q = abd_to_buf(rr->rr_col[VDEV_RAIDZ_Q].rc_abd);
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uint64_t pcnt = rr->rr_col[VDEV_RAIDZ_P].rc_size / sizeof (p[0]);
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ASSERT(rr->rr_col[VDEV_RAIDZ_P].rc_size ==
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rr->rr_col[VDEV_RAIDZ_Q].rc_size);
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for (int c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
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abd_t *src = rr->rr_col[c].rc_abd;
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uint64_t ccnt = rr->rr_col[c].rc_size / sizeof (p[0]);
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if (c == rr->rr_firstdatacol) {
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ASSERT(ccnt == pcnt || ccnt == 0);
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abd_copy_to_buf(p, src, rr->rr_col[c].rc_size);
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(void) memcpy(q, p, rr->rr_col[c].rc_size);
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for (uint64_t i = ccnt; i < pcnt; i++) {
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p[i] = 0;
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q[i] = 0;
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}
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} else {
|
|
struct pqr_struct pqr = { p, q, NULL };
|
|
|
|
ASSERT(ccnt <= pcnt);
|
|
(void) abd_iterate_func(src, 0, rr->rr_col[c].rc_size,
|
|
vdev_raidz_pq_func, &pqr);
|
|
|
|
/*
|
|
* Treat short columns as though they are full of 0s.
|
|
* Note that there's therefore nothing needed for P.
|
|
*/
|
|
uint64_t mask;
|
|
for (uint64_t i = ccnt; i < pcnt; i++) {
|
|
VDEV_RAIDZ_64MUL_2(q[i], mask);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_generate_parity_pqr(raidz_row_t *rr)
|
|
{
|
|
uint64_t *p = abd_to_buf(rr->rr_col[VDEV_RAIDZ_P].rc_abd);
|
|
uint64_t *q = abd_to_buf(rr->rr_col[VDEV_RAIDZ_Q].rc_abd);
|
|
uint64_t *r = abd_to_buf(rr->rr_col[VDEV_RAIDZ_R].rc_abd);
|
|
uint64_t pcnt = rr->rr_col[VDEV_RAIDZ_P].rc_size / sizeof (p[0]);
|
|
ASSERT(rr->rr_col[VDEV_RAIDZ_P].rc_size ==
|
|
rr->rr_col[VDEV_RAIDZ_Q].rc_size);
|
|
ASSERT(rr->rr_col[VDEV_RAIDZ_P].rc_size ==
|
|
rr->rr_col[VDEV_RAIDZ_R].rc_size);
|
|
|
|
for (int c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
abd_t *src = rr->rr_col[c].rc_abd;
|
|
|
|
uint64_t ccnt = rr->rr_col[c].rc_size / sizeof (p[0]);
|
|
|
|
if (c == rr->rr_firstdatacol) {
|
|
ASSERT(ccnt == pcnt || ccnt == 0);
|
|
abd_copy_to_buf(p, src, rr->rr_col[c].rc_size);
|
|
(void) memcpy(q, p, rr->rr_col[c].rc_size);
|
|
(void) memcpy(r, p, rr->rr_col[c].rc_size);
|
|
|
|
for (uint64_t i = ccnt; i < pcnt; i++) {
|
|
p[i] = 0;
|
|
q[i] = 0;
|
|
r[i] = 0;
|
|
}
|
|
} else {
|
|
struct pqr_struct pqr = { p, q, r };
|
|
|
|
ASSERT(ccnt <= pcnt);
|
|
(void) abd_iterate_func(src, 0, rr->rr_col[c].rc_size,
|
|
vdev_raidz_pqr_func, &pqr);
|
|
|
|
/*
|
|
* Treat short columns as though they are full of 0s.
|
|
* Note that there's therefore nothing needed for P.
|
|
*/
|
|
uint64_t mask;
|
|
for (uint64_t i = ccnt; i < pcnt; i++) {
|
|
VDEV_RAIDZ_64MUL_2(q[i], mask);
|
|
VDEV_RAIDZ_64MUL_4(r[i], mask);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Generate RAID parity in the first virtual columns according to the number of
|
|
* parity columns available.
|
|
*/
|
|
void
|
|
vdev_raidz_generate_parity_row(raidz_map_t *rm, raidz_row_t *rr)
|
|
{
|
|
ASSERT3U(rr->rr_cols, !=, 0);
|
|
|
|
/* Generate using the new math implementation */
|
|
if (vdev_raidz_math_generate(rm, rr) != RAIDZ_ORIGINAL_IMPL)
|
|
return;
|
|
|
|
switch (rr->rr_firstdatacol) {
|
|
case 1:
|
|
vdev_raidz_generate_parity_p(rr);
|
|
break;
|
|
case 2:
|
|
vdev_raidz_generate_parity_pq(rr);
|
|
break;
|
|
case 3:
|
|
vdev_raidz_generate_parity_pqr(rr);
|
|
break;
|
|
default:
|
|
cmn_err(CE_PANIC, "invalid RAID-Z configuration");
|
|
}
|
|
}
|
|
|
|
void
|
|
vdev_raidz_generate_parity(raidz_map_t *rm)
|
|
{
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
vdev_raidz_generate_parity_row(rm, rr);
|
|
}
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
vdev_raidz_reconst_p_func(void *dbuf, void *sbuf, size_t size, void *private)
|
|
{
|
|
uint64_t *dst = dbuf;
|
|
uint64_t *src = sbuf;
|
|
int cnt = size / sizeof (src[0]);
|
|
|
|
for (int i = 0; i < cnt; i++) {
|
|
dst[i] ^= src[i];
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
vdev_raidz_reconst_q_pre_func(void *dbuf, void *sbuf, size_t size,
|
|
void *private)
|
|
{
|
|
uint64_t *dst = dbuf;
|
|
uint64_t *src = sbuf;
|
|
uint64_t mask;
|
|
int cnt = size / sizeof (dst[0]);
|
|
|
|
for (int i = 0; i < cnt; i++, dst++, src++) {
|
|
VDEV_RAIDZ_64MUL_2(*dst, mask);
|
|
*dst ^= *src;
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
vdev_raidz_reconst_q_pre_tail_func(void *buf, size_t size, void *private)
|
|
{
|
|
uint64_t *dst = buf;
|
|
uint64_t mask;
|
|
int cnt = size / sizeof (dst[0]);
|
|
|
|
for (int i = 0; i < cnt; i++, dst++) {
|
|
/* same operation as vdev_raidz_reconst_q_pre_func() on dst */
|
|
VDEV_RAIDZ_64MUL_2(*dst, mask);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
struct reconst_q_struct {
|
|
uint64_t *q;
|
|
int exp;
|
|
};
|
|
|
|
static int
|
|
vdev_raidz_reconst_q_post_func(void *buf, size_t size, void *private)
|
|
{
|
|
struct reconst_q_struct *rq = private;
|
|
uint64_t *dst = buf;
|
|
int cnt = size / sizeof (dst[0]);
|
|
|
|
for (int i = 0; i < cnt; i++, dst++, rq->q++) {
|
|
int j;
|
|
uint8_t *b;
|
|
|
|
*dst ^= *rq->q;
|
|
for (j = 0, b = (uint8_t *)dst; j < 8; j++, b++) {
|
|
*b = vdev_raidz_exp2(*b, rq->exp);
|
|
}
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
struct reconst_pq_struct {
|
|
uint8_t *p;
|
|
uint8_t *q;
|
|
uint8_t *pxy;
|
|
uint8_t *qxy;
|
|
int aexp;
|
|
int bexp;
|
|
};
|
|
|
|
static int
|
|
vdev_raidz_reconst_pq_func(void *xbuf, void *ybuf, size_t size, void *private)
|
|
{
|
|
struct reconst_pq_struct *rpq = private;
|
|
uint8_t *xd = xbuf;
|
|
uint8_t *yd = ybuf;
|
|
|
|
for (int i = 0; i < size;
|
|
i++, rpq->p++, rpq->q++, rpq->pxy++, rpq->qxy++, xd++, yd++) {
|
|
*xd = vdev_raidz_exp2(*rpq->p ^ *rpq->pxy, rpq->aexp) ^
|
|
vdev_raidz_exp2(*rpq->q ^ *rpq->qxy, rpq->bexp);
|
|
*yd = *rpq->p ^ *rpq->pxy ^ *xd;
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
vdev_raidz_reconst_pq_tail_func(void *xbuf, size_t size, void *private)
|
|
{
|
|
struct reconst_pq_struct *rpq = private;
|
|
uint8_t *xd = xbuf;
|
|
|
|
for (int i = 0; i < size;
|
|
i++, rpq->p++, rpq->q++, rpq->pxy++, rpq->qxy++, xd++) {
|
|
/* same operation as vdev_raidz_reconst_pq_func() on xd */
|
|
*xd = vdev_raidz_exp2(*rpq->p ^ *rpq->pxy, rpq->aexp) ^
|
|
vdev_raidz_exp2(*rpq->q ^ *rpq->qxy, rpq->bexp);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_reconstruct_p(raidz_row_t *rr, int *tgts, int ntgts)
|
|
{
|
|
int x = tgts[0];
|
|
abd_t *dst, *src;
|
|
|
|
ASSERT3U(ntgts, ==, 1);
|
|
ASSERT3U(x, >=, rr->rr_firstdatacol);
|
|
ASSERT3U(x, <, rr->rr_cols);
|
|
|
|
ASSERT3U(rr->rr_col[x].rc_size, <=, rr->rr_col[VDEV_RAIDZ_P].rc_size);
|
|
|
|
src = rr->rr_col[VDEV_RAIDZ_P].rc_abd;
|
|
dst = rr->rr_col[x].rc_abd;
|
|
|
|
abd_copy_from_buf(dst, abd_to_buf(src), rr->rr_col[x].rc_size);
|
|
|
|
for (int c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
uint64_t size = MIN(rr->rr_col[x].rc_size,
|
|
rr->rr_col[c].rc_size);
|
|
|
|
src = rr->rr_col[c].rc_abd;
|
|
|
|
if (c == x)
|
|
continue;
|
|
|
|
(void) abd_iterate_func2(dst, src, 0, 0, size,
|
|
vdev_raidz_reconst_p_func, NULL);
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_reconstruct_q(raidz_row_t *rr, int *tgts, int ntgts)
|
|
{
|
|
int x = tgts[0];
|
|
int c, exp;
|
|
abd_t *dst, *src;
|
|
|
|
ASSERT(ntgts == 1);
|
|
|
|
ASSERT(rr->rr_col[x].rc_size <= rr->rr_col[VDEV_RAIDZ_Q].rc_size);
|
|
|
|
for (c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
uint64_t size = (c == x) ? 0 : MIN(rr->rr_col[x].rc_size,
|
|
rr->rr_col[c].rc_size);
|
|
|
|
src = rr->rr_col[c].rc_abd;
|
|
dst = rr->rr_col[x].rc_abd;
|
|
|
|
if (c == rr->rr_firstdatacol) {
|
|
abd_copy(dst, src, size);
|
|
if (rr->rr_col[x].rc_size > size) {
|
|
abd_zero_off(dst, size,
|
|
rr->rr_col[x].rc_size - size);
|
|
}
|
|
} else {
|
|
ASSERT3U(size, <=, rr->rr_col[x].rc_size);
|
|
(void) abd_iterate_func2(dst, src, 0, 0, size,
|
|
vdev_raidz_reconst_q_pre_func, NULL);
|
|
(void) abd_iterate_func(dst,
|
|
size, rr->rr_col[x].rc_size - size,
|
|
vdev_raidz_reconst_q_pre_tail_func, NULL);
|
|
}
|
|
}
|
|
|
|
src = rr->rr_col[VDEV_RAIDZ_Q].rc_abd;
|
|
dst = rr->rr_col[x].rc_abd;
|
|
exp = 255 - (rr->rr_cols - 1 - x);
|
|
|
|
struct reconst_q_struct rq = { abd_to_buf(src), exp };
|
|
(void) abd_iterate_func(dst, 0, rr->rr_col[x].rc_size,
|
|
vdev_raidz_reconst_q_post_func, &rq);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_reconstruct_pq(raidz_row_t *rr, int *tgts, int ntgts)
|
|
{
|
|
uint8_t *p, *q, *pxy, *qxy, tmp, a, b, aexp, bexp;
|
|
abd_t *pdata, *qdata;
|
|
uint64_t xsize, ysize;
|
|
int x = tgts[0];
|
|
int y = tgts[1];
|
|
abd_t *xd, *yd;
|
|
|
|
ASSERT(ntgts == 2);
|
|
ASSERT(x < y);
|
|
ASSERT(x >= rr->rr_firstdatacol);
|
|
ASSERT(y < rr->rr_cols);
|
|
|
|
ASSERT(rr->rr_col[x].rc_size >= rr->rr_col[y].rc_size);
|
|
|
|
/*
|
|
* Move the parity data aside -- we're going to compute parity as
|
|
* though columns x and y were full of zeros -- Pxy and Qxy. We want to
|
|
* reuse the parity generation mechanism without trashing the actual
|
|
* parity so we make those columns appear to be full of zeros by
|
|
* setting their lengths to zero.
|
|
*/
|
|
pdata = rr->rr_col[VDEV_RAIDZ_P].rc_abd;
|
|
qdata = rr->rr_col[VDEV_RAIDZ_Q].rc_abd;
|
|
xsize = rr->rr_col[x].rc_size;
|
|
ysize = rr->rr_col[y].rc_size;
|
|
|
|
rr->rr_col[VDEV_RAIDZ_P].rc_abd =
|
|
abd_alloc_linear(rr->rr_col[VDEV_RAIDZ_P].rc_size, B_TRUE);
|
|
rr->rr_col[VDEV_RAIDZ_Q].rc_abd =
|
|
abd_alloc_linear(rr->rr_col[VDEV_RAIDZ_Q].rc_size, B_TRUE);
|
|
rr->rr_col[x].rc_size = 0;
|
|
rr->rr_col[y].rc_size = 0;
|
|
|
|
vdev_raidz_generate_parity_pq(rr);
|
|
|
|
rr->rr_col[x].rc_size = xsize;
|
|
rr->rr_col[y].rc_size = ysize;
|
|
|
|
p = abd_to_buf(pdata);
|
|
q = abd_to_buf(qdata);
|
|
pxy = abd_to_buf(rr->rr_col[VDEV_RAIDZ_P].rc_abd);
|
|
qxy = abd_to_buf(rr->rr_col[VDEV_RAIDZ_Q].rc_abd);
|
|
xd = rr->rr_col[x].rc_abd;
|
|
yd = rr->rr_col[y].rc_abd;
|
|
|
|
/*
|
|
* We now have:
|
|
* Pxy = P + D_x + D_y
|
|
* Qxy = Q + 2^(ndevs - 1 - x) * D_x + 2^(ndevs - 1 - y) * D_y
|
|
*
|
|
* We can then solve for D_x:
|
|
* D_x = A * (P + Pxy) + B * (Q + Qxy)
|
|
* where
|
|
* A = 2^(x - y) * (2^(x - y) + 1)^-1
|
|
* B = 2^(ndevs - 1 - x) * (2^(x - y) + 1)^-1
|
|
*
|
|
* With D_x in hand, we can easily solve for D_y:
|
|
* D_y = P + Pxy + D_x
|
|
*/
|
|
|
|
a = vdev_raidz_pow2[255 + x - y];
|
|
b = vdev_raidz_pow2[255 - (rr->rr_cols - 1 - x)];
|
|
tmp = 255 - vdev_raidz_log2[a ^ 1];
|
|
|
|
aexp = vdev_raidz_log2[vdev_raidz_exp2(a, tmp)];
|
|
bexp = vdev_raidz_log2[vdev_raidz_exp2(b, tmp)];
|
|
|
|
ASSERT3U(xsize, >=, ysize);
|
|
struct reconst_pq_struct rpq = { p, q, pxy, qxy, aexp, bexp };
|
|
|
|
(void) abd_iterate_func2(xd, yd, 0, 0, ysize,
|
|
vdev_raidz_reconst_pq_func, &rpq);
|
|
(void) abd_iterate_func(xd, ysize, xsize - ysize,
|
|
vdev_raidz_reconst_pq_tail_func, &rpq);
|
|
|
|
abd_free(rr->rr_col[VDEV_RAIDZ_P].rc_abd);
|
|
abd_free(rr->rr_col[VDEV_RAIDZ_Q].rc_abd);
|
|
|
|
/*
|
|
* Restore the saved parity data.
|
|
*/
|
|
rr->rr_col[VDEV_RAIDZ_P].rc_abd = pdata;
|
|
rr->rr_col[VDEV_RAIDZ_Q].rc_abd = qdata;
|
|
}
|
|
|
|
/* BEGIN CSTYLED */
|
|
/*
|
|
* In the general case of reconstruction, we must solve the system of linear
|
|
* equations defined by the coefficients used to generate parity as well as
|
|
* the contents of the data and parity disks. This can be expressed with
|
|
* vectors for the original data (D) and the actual data (d) and parity (p)
|
|
* and a matrix composed of the identity matrix (I) and a dispersal matrix (V):
|
|
*
|
|
* __ __ __ __
|
|
* | | __ __ | p_0 |
|
|
* | V | | D_0 | | p_m-1 |
|
|
* | | x | : | = | d_0 |
|
|
* | I | | D_n-1 | | : |
|
|
* | | ~~ ~~ | d_n-1 |
|
|
* ~~ ~~ ~~ ~~
|
|
*
|
|
* I is simply a square identity matrix of size n, and V is a vandermonde
|
|
* matrix defined by the coefficients we chose for the various parity columns
|
|
* (1, 2, 4). Note that these values were chosen both for simplicity, speedy
|
|
* computation as well as linear separability.
|
|
*
|
|
* __ __ __ __
|
|
* | 1 .. 1 1 1 | | p_0 |
|
|
* | 2^n-1 .. 4 2 1 | __ __ | : |
|
|
* | 4^n-1 .. 16 4 1 | | D_0 | | p_m-1 |
|
|
* | 1 .. 0 0 0 | | D_1 | | d_0 |
|
|
* | 0 .. 0 0 0 | x | D_2 | = | d_1 |
|
|
* | : : : : | | : | | d_2 |
|
|
* | 0 .. 1 0 0 | | D_n-1 | | : |
|
|
* | 0 .. 0 1 0 | ~~ ~~ | : |
|
|
* | 0 .. 0 0 1 | | d_n-1 |
|
|
* ~~ ~~ ~~ ~~
|
|
*
|
|
* Note that I, V, d, and p are known. To compute D, we must invert the
|
|
* matrix and use the known data and parity values to reconstruct the unknown
|
|
* data values. We begin by removing the rows in V|I and d|p that correspond
|
|
* to failed or missing columns; we then make V|I square (n x n) and d|p
|
|
* sized n by removing rows corresponding to unused parity from the bottom up
|
|
* to generate (V|I)' and (d|p)'. We can then generate the inverse of (V|I)'
|
|
* using Gauss-Jordan elimination. In the example below we use m=3 parity
|
|
* columns, n=8 data columns, with errors in d_1, d_2, and p_1:
|
|
* __ __
|
|
* | 1 1 1 1 1 1 1 1 |
|
|
* | 128 64 32 16 8 4 2 1 | <-----+-+-- missing disks
|
|
* | 19 205 116 29 64 16 4 1 | / /
|
|
* | 1 0 0 0 0 0 0 0 | / /
|
|
* | 0 1 0 0 0 0 0 0 | <--' /
|
|
* (V|I) = | 0 0 1 0 0 0 0 0 | <---'
|
|
* | 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 1 1 1 1 1 1 1 |
|
|
* | 128 64 32 16 8 4 2 1 |
|
|
* | 19 205 116 29 64 16 4 1 |
|
|
* | 1 0 0 0 0 0 0 0 |
|
|
* | 0 1 0 0 0 0 0 0 |
|
|
* (V|I)' = | 0 0 1 0 0 0 0 0 |
|
|
* | 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
*
|
|
* Here we employ Gauss-Jordan elimination to find the inverse of (V|I)'. We
|
|
* have carefully chosen the seed values 1, 2, and 4 to ensure that this
|
|
* matrix is not singular.
|
|
* __ __
|
|
* | 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 |
|
|
* | 19 205 116 29 64 16 4 1 0 1 0 0 0 0 0 0 |
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 |
|
|
* | 19 205 116 29 64 16 4 1 0 1 0 0 0 0 0 0 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 0 1 1 0 0 0 0 0 1 0 1 1 1 1 1 1 |
|
|
* | 0 205 116 0 0 0 0 0 0 1 19 29 64 16 4 1 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 0 1 1 0 0 0 0 0 1 0 1 1 1 1 1 1 |
|
|
* | 0 0 185 0 0 0 0 0 205 1 222 208 141 221 201 204 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 0 1 1 0 0 0 0 0 1 0 1 1 1 1 1 1 |
|
|
* | 0 0 1 0 0 0 0 0 166 100 4 40 158 168 216 209 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 |
|
|
* | 0 1 0 0 0 0 0 0 167 100 5 41 159 169 217 208 |
|
|
* | 0 0 1 0 0 0 0 0 166 100 4 40 158 168 216 209 |
|
|
* | 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
* __ __
|
|
* | 0 0 1 0 0 0 0 0 |
|
|
* | 167 100 5 41 159 169 217 208 |
|
|
* | 166 100 4 40 158 168 216 209 |
|
|
* (V|I)'^-1 = | 0 0 0 1 0 0 0 0 |
|
|
* | 0 0 0 0 1 0 0 0 |
|
|
* | 0 0 0 0 0 1 0 0 |
|
|
* | 0 0 0 0 0 0 1 0 |
|
|
* | 0 0 0 0 0 0 0 1 |
|
|
* ~~ ~~
|
|
*
|
|
* We can then simply compute D = (V|I)'^-1 x (d|p)' to discover the values
|
|
* of the missing data.
|
|
*
|
|
* As is apparent from the example above, the only non-trivial rows in the
|
|
* inverse matrix correspond to the data disks that we're trying to
|
|
* reconstruct. Indeed, those are the only rows we need as the others would
|
|
* only be useful for reconstructing data known or assumed to be valid. For
|
|
* that reason, we only build the coefficients in the rows that correspond to
|
|
* targeted columns.
|
|
*/
|
|
/* END CSTYLED */
|
|
|
|
static void
|
|
vdev_raidz_matrix_init(raidz_row_t *rr, int n, int nmap, int *map,
|
|
uint8_t **rows)
|
|
{
|
|
int i, j;
|
|
int pow;
|
|
|
|
ASSERT(n == rr->rr_cols - rr->rr_firstdatacol);
|
|
|
|
/*
|
|
* Fill in the missing rows of interest.
|
|
*/
|
|
for (i = 0; i < nmap; i++) {
|
|
ASSERT3S(0, <=, map[i]);
|
|
ASSERT3S(map[i], <=, 2);
|
|
|
|
pow = map[i] * n;
|
|
if (pow > 255)
|
|
pow -= 255;
|
|
ASSERT(pow <= 255);
|
|
|
|
for (j = 0; j < n; j++) {
|
|
pow -= map[i];
|
|
if (pow < 0)
|
|
pow += 255;
|
|
rows[i][j] = vdev_raidz_pow2[pow];
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_matrix_invert(raidz_row_t *rr, int n, int nmissing, int *missing,
|
|
uint8_t **rows, uint8_t **invrows, const uint8_t *used)
|
|
{
|
|
int i, j, ii, jj;
|
|
uint8_t log;
|
|
|
|
/*
|
|
* Assert that the first nmissing entries from the array of used
|
|
* columns correspond to parity columns and that subsequent entries
|
|
* correspond to data columns.
|
|
*/
|
|
for (i = 0; i < nmissing; i++) {
|
|
ASSERT3S(used[i], <, rr->rr_firstdatacol);
|
|
}
|
|
for (; i < n; i++) {
|
|
ASSERT3S(used[i], >=, rr->rr_firstdatacol);
|
|
}
|
|
|
|
/*
|
|
* First initialize the storage where we'll compute the inverse rows.
|
|
*/
|
|
for (i = 0; i < nmissing; i++) {
|
|
for (j = 0; j < n; j++) {
|
|
invrows[i][j] = (i == j) ? 1 : 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Subtract all trivial rows from the rows of consequence.
|
|
*/
|
|
for (i = 0; i < nmissing; i++) {
|
|
for (j = nmissing; j < n; j++) {
|
|
ASSERT3U(used[j], >=, rr->rr_firstdatacol);
|
|
jj = used[j] - rr->rr_firstdatacol;
|
|
ASSERT3S(jj, <, n);
|
|
invrows[i][j] = rows[i][jj];
|
|
rows[i][jj] = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* For each of the rows of interest, we must normalize it and subtract
|
|
* a multiple of it from the other rows.
|
|
*/
|
|
for (i = 0; i < nmissing; i++) {
|
|
for (j = 0; j < missing[i]; j++) {
|
|
ASSERT0(rows[i][j]);
|
|
}
|
|
ASSERT3U(rows[i][missing[i]], !=, 0);
|
|
|
|
/*
|
|
* Compute the inverse of the first element and multiply each
|
|
* element in the row by that value.
|
|
*/
|
|
log = 255 - vdev_raidz_log2[rows[i][missing[i]]];
|
|
|
|
for (j = 0; j < n; j++) {
|
|
rows[i][j] = vdev_raidz_exp2(rows[i][j], log);
|
|
invrows[i][j] = vdev_raidz_exp2(invrows[i][j], log);
|
|
}
|
|
|
|
for (ii = 0; ii < nmissing; ii++) {
|
|
if (i == ii)
|
|
continue;
|
|
|
|
ASSERT3U(rows[ii][missing[i]], !=, 0);
|
|
|
|
log = vdev_raidz_log2[rows[ii][missing[i]]];
|
|
|
|
for (j = 0; j < n; j++) {
|
|
rows[ii][j] ^=
|
|
vdev_raidz_exp2(rows[i][j], log);
|
|
invrows[ii][j] ^=
|
|
vdev_raidz_exp2(invrows[i][j], log);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Verify that the data that is left in the rows are properly part of
|
|
* an identity matrix.
|
|
*/
|
|
for (i = 0; i < nmissing; i++) {
|
|
for (j = 0; j < n; j++) {
|
|
if (j == missing[i]) {
|
|
ASSERT3U(rows[i][j], ==, 1);
|
|
} else {
|
|
ASSERT0(rows[i][j]);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_matrix_reconstruct(raidz_row_t *rr, int n, int nmissing,
|
|
int *missing, uint8_t **invrows, const uint8_t *used)
|
|
{
|
|
int i, j, x, cc, c;
|
|
uint8_t *src;
|
|
uint64_t ccount;
|
|
uint8_t *dst[VDEV_RAIDZ_MAXPARITY] = { NULL };
|
|
uint64_t dcount[VDEV_RAIDZ_MAXPARITY] = { 0 };
|
|
uint8_t log = 0;
|
|
uint8_t val;
|
|
int ll;
|
|
uint8_t *invlog[VDEV_RAIDZ_MAXPARITY];
|
|
uint8_t *p, *pp;
|
|
size_t psize;
|
|
|
|
psize = sizeof (invlog[0][0]) * n * nmissing;
|
|
p = kmem_alloc(psize, KM_SLEEP);
|
|
|
|
for (pp = p, i = 0; i < nmissing; i++) {
|
|
invlog[i] = pp;
|
|
pp += n;
|
|
}
|
|
|
|
for (i = 0; i < nmissing; i++) {
|
|
for (j = 0; j < n; j++) {
|
|
ASSERT3U(invrows[i][j], !=, 0);
|
|
invlog[i][j] = vdev_raidz_log2[invrows[i][j]];
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < n; i++) {
|
|
c = used[i];
|
|
ASSERT3U(c, <, rr->rr_cols);
|
|
|
|
ccount = rr->rr_col[c].rc_size;
|
|
ASSERT(ccount >= rr->rr_col[missing[0]].rc_size || i > 0);
|
|
if (ccount == 0)
|
|
continue;
|
|
src = abd_to_buf(rr->rr_col[c].rc_abd);
|
|
for (j = 0; j < nmissing; j++) {
|
|
cc = missing[j] + rr->rr_firstdatacol;
|
|
ASSERT3U(cc, >=, rr->rr_firstdatacol);
|
|
ASSERT3U(cc, <, rr->rr_cols);
|
|
ASSERT3U(cc, !=, c);
|
|
|
|
dcount[j] = rr->rr_col[cc].rc_size;
|
|
if (dcount[j] != 0)
|
|
dst[j] = abd_to_buf(rr->rr_col[cc].rc_abd);
|
|
}
|
|
|
|
for (x = 0; x < ccount; x++, src++) {
|
|
if (*src != 0)
|
|
log = vdev_raidz_log2[*src];
|
|
|
|
for (cc = 0; cc < nmissing; cc++) {
|
|
if (x >= dcount[cc])
|
|
continue;
|
|
|
|
if (*src == 0) {
|
|
val = 0;
|
|
} else {
|
|
if ((ll = log + invlog[cc][i]) >= 255)
|
|
ll -= 255;
|
|
val = vdev_raidz_pow2[ll];
|
|
}
|
|
|
|
if (i == 0)
|
|
dst[cc][x] = val;
|
|
else
|
|
dst[cc][x] ^= val;
|
|
}
|
|
}
|
|
}
|
|
|
|
kmem_free(p, psize);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_reconstruct_general(raidz_row_t *rr, int *tgts, int ntgts)
|
|
{
|
|
int n, i, c, t, tt;
|
|
int nmissing_rows;
|
|
int missing_rows[VDEV_RAIDZ_MAXPARITY];
|
|
int parity_map[VDEV_RAIDZ_MAXPARITY];
|
|
uint8_t *p, *pp;
|
|
size_t psize;
|
|
uint8_t *rows[VDEV_RAIDZ_MAXPARITY];
|
|
uint8_t *invrows[VDEV_RAIDZ_MAXPARITY];
|
|
uint8_t *used;
|
|
|
|
abd_t **bufs = NULL;
|
|
|
|
/*
|
|
* Matrix reconstruction can't use scatter ABDs yet, so we allocate
|
|
* temporary linear ABDs if any non-linear ABDs are found.
|
|
*/
|
|
for (i = rr->rr_firstdatacol; i < rr->rr_cols; i++) {
|
|
if (!abd_is_linear(rr->rr_col[i].rc_abd)) {
|
|
bufs = kmem_alloc(rr->rr_cols * sizeof (abd_t *),
|
|
KM_PUSHPAGE);
|
|
|
|
for (c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
raidz_col_t *col = &rr->rr_col[c];
|
|
|
|
bufs[c] = col->rc_abd;
|
|
if (bufs[c] != NULL) {
|
|
col->rc_abd = abd_alloc_linear(
|
|
col->rc_size, B_TRUE);
|
|
abd_copy(col->rc_abd, bufs[c],
|
|
col->rc_size);
|
|
}
|
|
}
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
n = rr->rr_cols - rr->rr_firstdatacol;
|
|
|
|
/*
|
|
* Figure out which data columns are missing.
|
|
*/
|
|
nmissing_rows = 0;
|
|
for (t = 0; t < ntgts; t++) {
|
|
if (tgts[t] >= rr->rr_firstdatacol) {
|
|
missing_rows[nmissing_rows++] =
|
|
tgts[t] - rr->rr_firstdatacol;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Figure out which parity columns to use to help generate the missing
|
|
* data columns.
|
|
*/
|
|
for (tt = 0, c = 0, i = 0; i < nmissing_rows; c++) {
|
|
ASSERT(tt < ntgts);
|
|
ASSERT(c < rr->rr_firstdatacol);
|
|
|
|
/*
|
|
* Skip any targeted parity columns.
|
|
*/
|
|
if (c == tgts[tt]) {
|
|
tt++;
|
|
continue;
|
|
}
|
|
|
|
parity_map[i] = c;
|
|
i++;
|
|
}
|
|
|
|
psize = (sizeof (rows[0][0]) + sizeof (invrows[0][0])) *
|
|
nmissing_rows * n + sizeof (used[0]) * n;
|
|
p = kmem_alloc(psize, KM_SLEEP);
|
|
|
|
for (pp = p, i = 0; i < nmissing_rows; i++) {
|
|
rows[i] = pp;
|
|
pp += n;
|
|
invrows[i] = pp;
|
|
pp += n;
|
|
}
|
|
used = pp;
|
|
|
|
for (i = 0; i < nmissing_rows; i++) {
|
|
used[i] = parity_map[i];
|
|
}
|
|
|
|
for (tt = 0, c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
if (tt < nmissing_rows &&
|
|
c == missing_rows[tt] + rr->rr_firstdatacol) {
|
|
tt++;
|
|
continue;
|
|
}
|
|
|
|
ASSERT3S(i, <, n);
|
|
used[i] = c;
|
|
i++;
|
|
}
|
|
|
|
/*
|
|
* Initialize the interesting rows of the matrix.
|
|
*/
|
|
vdev_raidz_matrix_init(rr, n, nmissing_rows, parity_map, rows);
|
|
|
|
/*
|
|
* Invert the matrix.
|
|
*/
|
|
vdev_raidz_matrix_invert(rr, n, nmissing_rows, missing_rows, rows,
|
|
invrows, used);
|
|
|
|
/*
|
|
* Reconstruct the missing data using the generated matrix.
|
|
*/
|
|
vdev_raidz_matrix_reconstruct(rr, n, nmissing_rows, missing_rows,
|
|
invrows, used);
|
|
|
|
kmem_free(p, psize);
|
|
|
|
/*
|
|
* copy back from temporary linear abds and free them
|
|
*/
|
|
if (bufs) {
|
|
for (c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
raidz_col_t *col = &rr->rr_col[c];
|
|
|
|
if (bufs[c] != NULL) {
|
|
abd_copy(bufs[c], col->rc_abd, col->rc_size);
|
|
abd_free(col->rc_abd);
|
|
}
|
|
col->rc_abd = bufs[c];
|
|
}
|
|
kmem_free(bufs, rr->rr_cols * sizeof (abd_t *));
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_reconstruct_row(raidz_map_t *rm, raidz_row_t *rr,
|
|
const int *t, int nt)
|
|
{
|
|
int tgts[VDEV_RAIDZ_MAXPARITY], *dt;
|
|
int ntgts;
|
|
int i, c, ret;
|
|
int nbadparity, nbaddata;
|
|
int parity_valid[VDEV_RAIDZ_MAXPARITY];
|
|
|
|
nbadparity = rr->rr_firstdatacol;
|
|
nbaddata = rr->rr_cols - nbadparity;
|
|
ntgts = 0;
|
|
for (i = 0, c = 0; c < rr->rr_cols; c++) {
|
|
if (c < rr->rr_firstdatacol)
|
|
parity_valid[c] = B_FALSE;
|
|
|
|
if (i < nt && c == t[i]) {
|
|
tgts[ntgts++] = c;
|
|
i++;
|
|
} else if (rr->rr_col[c].rc_error != 0) {
|
|
tgts[ntgts++] = c;
|
|
} else if (c >= rr->rr_firstdatacol) {
|
|
nbaddata--;
|
|
} else {
|
|
parity_valid[c] = B_TRUE;
|
|
nbadparity--;
|
|
}
|
|
}
|
|
|
|
ASSERT(ntgts >= nt);
|
|
ASSERT(nbaddata >= 0);
|
|
ASSERT(nbaddata + nbadparity == ntgts);
|
|
|
|
dt = &tgts[nbadparity];
|
|
|
|
/* Reconstruct using the new math implementation */
|
|
ret = vdev_raidz_math_reconstruct(rm, rr, parity_valid, dt, nbaddata);
|
|
if (ret != RAIDZ_ORIGINAL_IMPL)
|
|
return;
|
|
|
|
/*
|
|
* See if we can use any of our optimized reconstruction routines.
|
|
*/
|
|
switch (nbaddata) {
|
|
case 1:
|
|
if (parity_valid[VDEV_RAIDZ_P]) {
|
|
vdev_raidz_reconstruct_p(rr, dt, 1);
|
|
return;
|
|
}
|
|
|
|
ASSERT(rr->rr_firstdatacol > 1);
|
|
|
|
if (parity_valid[VDEV_RAIDZ_Q]) {
|
|
vdev_raidz_reconstruct_q(rr, dt, 1);
|
|
return;
|
|
}
|
|
|
|
ASSERT(rr->rr_firstdatacol > 2);
|
|
break;
|
|
|
|
case 2:
|
|
ASSERT(rr->rr_firstdatacol > 1);
|
|
|
|
if (parity_valid[VDEV_RAIDZ_P] &&
|
|
parity_valid[VDEV_RAIDZ_Q]) {
|
|
vdev_raidz_reconstruct_pq(rr, dt, 2);
|
|
return;
|
|
}
|
|
|
|
ASSERT(rr->rr_firstdatacol > 2);
|
|
|
|
break;
|
|
}
|
|
|
|
vdev_raidz_reconstruct_general(rr, tgts, ntgts);
|
|
}
|
|
|
|
static int
|
|
vdev_raidz_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize,
|
|
uint64_t *logical_ashift, uint64_t *physical_ashift)
|
|
{
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
uint64_t nparity = vdrz->vd_nparity;
|
|
int c;
|
|
int lasterror = 0;
|
|
int numerrors = 0;
|
|
|
|
ASSERT(nparity > 0);
|
|
|
|
if (nparity > VDEV_RAIDZ_MAXPARITY ||
|
|
vd->vdev_children < nparity + 1) {
|
|
vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
|
|
return (SET_ERROR(EINVAL));
|
|
}
|
|
|
|
vdev_open_children(vd);
|
|
|
|
for (c = 0; c < vd->vdev_children; c++) {
|
|
vdev_t *cvd = vd->vdev_child[c];
|
|
|
|
if (cvd->vdev_open_error != 0) {
|
|
lasterror = cvd->vdev_open_error;
|
|
numerrors++;
|
|
continue;
|
|
}
|
|
|
|
*asize = MIN(*asize - 1, cvd->vdev_asize - 1) + 1;
|
|
*max_asize = MIN(*max_asize - 1, cvd->vdev_max_asize - 1) + 1;
|
|
*logical_ashift = MAX(*logical_ashift, cvd->vdev_ashift);
|
|
*physical_ashift = MAX(*physical_ashift,
|
|
cvd->vdev_physical_ashift);
|
|
}
|
|
|
|
*asize *= vd->vdev_children;
|
|
*max_asize *= vd->vdev_children;
|
|
|
|
if (numerrors > nparity) {
|
|
vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
|
|
return (lasterror);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_close(vdev_t *vd)
|
|
{
|
|
for (int c = 0; c < vd->vdev_children; c++) {
|
|
if (vd->vdev_child[c] != NULL)
|
|
vdev_close(vd->vdev_child[c]);
|
|
}
|
|
}
|
|
|
|
static uint64_t
|
|
vdev_raidz_asize(vdev_t *vd, uint64_t psize)
|
|
{
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
uint64_t asize;
|
|
uint64_t ashift = vd->vdev_top->vdev_ashift;
|
|
uint64_t cols = vdrz->vd_logical_width;
|
|
uint64_t nparity = vdrz->vd_nparity;
|
|
|
|
asize = ((psize - 1) >> ashift) + 1;
|
|
asize += nparity * ((asize + cols - nparity - 1) / (cols - nparity));
|
|
asize = roundup(asize, nparity + 1) << ashift;
|
|
|
|
return (asize);
|
|
}
|
|
|
|
/*
|
|
* The allocatable space for a raidz vdev is N * sizeof(smallest child)
|
|
* so each child must provide at least 1/Nth of its asize.
|
|
*/
|
|
static uint64_t
|
|
vdev_raidz_min_asize(vdev_t *vd)
|
|
{
|
|
return ((vd->vdev_min_asize + vd->vdev_children - 1) /
|
|
vd->vdev_children);
|
|
}
|
|
|
|
void
|
|
vdev_raidz_child_done(zio_t *zio)
|
|
{
|
|
raidz_col_t *rc = zio->io_private;
|
|
|
|
rc->rc_error = zio->io_error;
|
|
rc->rc_tried = 1;
|
|
rc->rc_skipped = 0;
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_io_verify(vdev_t *vd, raidz_row_t *rr, int col)
|
|
{
|
|
#ifdef ZFS_DEBUG
|
|
vdev_t *tvd = vd->vdev_top;
|
|
|
|
range_seg64_t logical_rs, physical_rs, remain_rs;
|
|
logical_rs.rs_start = rr->rr_offset;
|
|
logical_rs.rs_end = logical_rs.rs_start +
|
|
vdev_raidz_asize(vd, rr->rr_size);
|
|
|
|
raidz_col_t *rc = &rr->rr_col[col];
|
|
vdev_t *cvd = vd->vdev_child[rc->rc_devidx];
|
|
|
|
vdev_xlate(cvd, &logical_rs, &physical_rs, &remain_rs);
|
|
ASSERT(vdev_xlate_is_empty(&remain_rs));
|
|
ASSERT3U(rc->rc_offset, ==, physical_rs.rs_start);
|
|
ASSERT3U(rc->rc_offset, <, physical_rs.rs_end);
|
|
/*
|
|
* It would be nice to assert that rs_end is equal
|
|
* to rc_offset + rc_size but there might be an
|
|
* optional I/O at the end that is not accounted in
|
|
* rc_size.
|
|
*/
|
|
if (physical_rs.rs_end > rc->rc_offset + rc->rc_size) {
|
|
ASSERT3U(physical_rs.rs_end, ==, rc->rc_offset +
|
|
rc->rc_size + (1 << tvd->vdev_ashift));
|
|
} else {
|
|
ASSERT3U(physical_rs.rs_end, ==, rc->rc_offset + rc->rc_size);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_io_start_write(zio_t *zio, raidz_row_t *rr, uint64_t ashift)
|
|
{
|
|
vdev_t *vd = zio->io_vd;
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
int c, i;
|
|
|
|
vdev_raidz_generate_parity_row(rm, rr);
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_size == 0)
|
|
continue;
|
|
|
|
/* Verify physical to logical translation */
|
|
vdev_raidz_io_verify(vd, rr, c);
|
|
|
|
zio_nowait(zio_vdev_child_io(zio, NULL,
|
|
vd->vdev_child[rc->rc_devidx], rc->rc_offset,
|
|
rc->rc_abd, rc->rc_size, zio->io_type, zio->io_priority,
|
|
0, vdev_raidz_child_done, rc));
|
|
}
|
|
|
|
/*
|
|
* Generate optional I/Os for skip sectors to improve aggregation
|
|
* contiguity.
|
|
*/
|
|
for (c = rm->rm_skipstart, i = 0; i < rm->rm_nskip; c++, i++) {
|
|
ASSERT(c <= rr->rr_scols);
|
|
if (c == rr->rr_scols)
|
|
c = 0;
|
|
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
vdev_t *cvd = vd->vdev_child[rc->rc_devidx];
|
|
|
|
zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
|
|
rc->rc_offset + rc->rc_size, NULL, 1ULL << ashift,
|
|
zio->io_type, zio->io_priority,
|
|
ZIO_FLAG_NODATA | ZIO_FLAG_OPTIONAL, NULL, NULL));
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_io_start_read(zio_t *zio, raidz_row_t *rr)
|
|
{
|
|
vdev_t *vd = zio->io_vd;
|
|
|
|
/*
|
|
* Iterate over the columns in reverse order so that we hit the parity
|
|
* last -- any errors along the way will force us to read the parity.
|
|
*/
|
|
for (int c = rr->rr_cols - 1; c >= 0; c--) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_size == 0)
|
|
continue;
|
|
vdev_t *cvd = vd->vdev_child[rc->rc_devidx];
|
|
if (!vdev_readable(cvd)) {
|
|
if (c >= rr->rr_firstdatacol)
|
|
rr->rr_missingdata++;
|
|
else
|
|
rr->rr_missingparity++;
|
|
rc->rc_error = SET_ERROR(ENXIO);
|
|
rc->rc_tried = 1; /* don't even try */
|
|
rc->rc_skipped = 1;
|
|
continue;
|
|
}
|
|
if (vdev_dtl_contains(cvd, DTL_MISSING, zio->io_txg, 1)) {
|
|
if (c >= rr->rr_firstdatacol)
|
|
rr->rr_missingdata++;
|
|
else
|
|
rr->rr_missingparity++;
|
|
rc->rc_error = SET_ERROR(ESTALE);
|
|
rc->rc_skipped = 1;
|
|
continue;
|
|
}
|
|
if (c >= rr->rr_firstdatacol || rr->rr_missingdata > 0 ||
|
|
(zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) {
|
|
zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
|
|
rc->rc_offset, rc->rc_abd, rc->rc_size,
|
|
zio->io_type, zio->io_priority, 0,
|
|
vdev_raidz_child_done, rc));
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Start an IO operation on a RAIDZ VDev
|
|
*
|
|
* Outline:
|
|
* - For write operations:
|
|
* 1. Generate the parity data
|
|
* 2. Create child zio write operations to each column's vdev, for both
|
|
* data and parity.
|
|
* 3. If the column skips any sectors for padding, create optional dummy
|
|
* write zio children for those areas to improve aggregation continuity.
|
|
* - For read operations:
|
|
* 1. Create child zio read operations to each data column's vdev to read
|
|
* the range of data required for zio.
|
|
* 2. If this is a scrub or resilver operation, or if any of the data
|
|
* vdevs have had errors, then create zio read operations to the parity
|
|
* columns' VDevs as well.
|
|
*/
|
|
static void
|
|
vdev_raidz_io_start(zio_t *zio)
|
|
{
|
|
vdev_t *vd = zio->io_vd;
|
|
vdev_t *tvd = vd->vdev_top;
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
|
|
raidz_map_t *rm = vdev_raidz_map_alloc(zio, tvd->vdev_ashift,
|
|
vdrz->vd_logical_width, vdrz->vd_nparity);
|
|
zio->io_vsd = rm;
|
|
zio->io_vsd_ops = &vdev_raidz_vsd_ops;
|
|
|
|
/*
|
|
* Until raidz expansion is implemented all maps for a raidz vdev
|
|
* contain a single row.
|
|
*/
|
|
ASSERT3U(rm->rm_nrows, ==, 1);
|
|
raidz_row_t *rr = rm->rm_row[0];
|
|
|
|
if (zio->io_type == ZIO_TYPE_WRITE) {
|
|
vdev_raidz_io_start_write(zio, rr, tvd->vdev_ashift);
|
|
} else {
|
|
ASSERT(zio->io_type == ZIO_TYPE_READ);
|
|
vdev_raidz_io_start_read(zio, rr);
|
|
}
|
|
|
|
zio_execute(zio);
|
|
}
|
|
|
|
/*
|
|
* Report a checksum error for a child of a RAID-Z device.
|
|
*/
|
|
static void
|
|
raidz_checksum_error(zio_t *zio, raidz_col_t *rc, abd_t *bad_data)
|
|
{
|
|
vdev_t *vd = zio->io_vd->vdev_child[rc->rc_devidx];
|
|
|
|
if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE) &&
|
|
zio->io_priority != ZIO_PRIORITY_REBUILD) {
|
|
zio_bad_cksum_t zbc;
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
zbc.zbc_has_cksum = 0;
|
|
zbc.zbc_injected = rm->rm_ecksuminjected;
|
|
|
|
(void) zfs_ereport_post_checksum(zio->io_spa, vd,
|
|
&zio->io_bookmark, zio, rc->rc_offset, rc->rc_size,
|
|
rc->rc_abd, bad_data, &zbc);
|
|
mutex_enter(&vd->vdev_stat_lock);
|
|
vd->vdev_stat.vs_checksum_errors++;
|
|
mutex_exit(&vd->vdev_stat_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We keep track of whether or not there were any injected errors, so that
|
|
* any ereports we generate can note it.
|
|
*/
|
|
static int
|
|
raidz_checksum_verify(zio_t *zio)
|
|
{
|
|
zio_bad_cksum_t zbc;
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
bzero(&zbc, sizeof (zio_bad_cksum_t));
|
|
|
|
int ret = zio_checksum_error(zio, &zbc);
|
|
if (ret != 0 && zbc.zbc_injected != 0)
|
|
rm->rm_ecksuminjected = 1;
|
|
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* Generate the parity from the data columns. If we tried and were able to
|
|
* read the parity without error, verify that the generated parity matches the
|
|
* data we read. If it doesn't, we fire off a checksum error. Return the
|
|
* number of such failures.
|
|
*/
|
|
static int
|
|
raidz_parity_verify(zio_t *zio, raidz_row_t *rr)
|
|
{
|
|
abd_t *orig[VDEV_RAIDZ_MAXPARITY];
|
|
int c, ret = 0;
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
raidz_col_t *rc;
|
|
|
|
blkptr_t *bp = zio->io_bp;
|
|
enum zio_checksum checksum = (bp == NULL ? zio->io_prop.zp_checksum :
|
|
(BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : BP_GET_CHECKSUM(bp)));
|
|
|
|
if (checksum == ZIO_CHECKSUM_NOPARITY)
|
|
return (ret);
|
|
|
|
for (c = 0; c < rr->rr_firstdatacol; c++) {
|
|
rc = &rr->rr_col[c];
|
|
if (!rc->rc_tried || rc->rc_error != 0)
|
|
continue;
|
|
|
|
orig[c] = abd_alloc_sametype(rc->rc_abd, rc->rc_size);
|
|
abd_copy(orig[c], rc->rc_abd, rc->rc_size);
|
|
}
|
|
|
|
/*
|
|
* Regenerates parity even for !tried||rc_error!=0 columns. This
|
|
* isn't harmful but it does have the side effect of fixing stuff
|
|
* we didn't realize was necessary (i.e. even if we return 0).
|
|
*/
|
|
vdev_raidz_generate_parity_row(rm, rr);
|
|
|
|
for (c = 0; c < rr->rr_firstdatacol; c++) {
|
|
rc = &rr->rr_col[c];
|
|
|
|
if (!rc->rc_tried || rc->rc_error != 0)
|
|
continue;
|
|
|
|
if (abd_cmp(orig[c], rc->rc_abd) != 0) {
|
|
raidz_checksum_error(zio, rc, orig[c]);
|
|
rc->rc_error = SET_ERROR(ECKSUM);
|
|
ret++;
|
|
}
|
|
abd_free(orig[c]);
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static int
|
|
vdev_raidz_worst_error(raidz_row_t *rr)
|
|
{
|
|
int error = 0;
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++)
|
|
error = zio_worst_error(error, rr->rr_col[c].rc_error);
|
|
|
|
return (error);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_io_done_verified(zio_t *zio, raidz_row_t *rr)
|
|
{
|
|
int unexpected_errors = 0;
|
|
int parity_errors = 0;
|
|
int parity_untried = 0;
|
|
int data_errors = 0;
|
|
|
|
ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ);
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
|
|
if (rc->rc_error) {
|
|
if (c < rr->rr_firstdatacol)
|
|
parity_errors++;
|
|
else
|
|
data_errors++;
|
|
|
|
if (!rc->rc_skipped)
|
|
unexpected_errors++;
|
|
} else if (c < rr->rr_firstdatacol && !rc->rc_tried) {
|
|
parity_untried++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we read more parity disks than were used for
|
|
* reconstruction, confirm that the other parity disks produced
|
|
* correct data.
|
|
*
|
|
* Note that we also regenerate parity when resilvering so we
|
|
* can write it out to failed devices later.
|
|
*/
|
|
if (parity_errors + parity_untried <
|
|
rr->rr_firstdatacol - data_errors ||
|
|
(zio->io_flags & ZIO_FLAG_RESILVER)) {
|
|
int n = raidz_parity_verify(zio, rr);
|
|
unexpected_errors += n;
|
|
ASSERT3U(parity_errors + n, <=, rr->rr_firstdatacol);
|
|
}
|
|
|
|
if (zio->io_error == 0 && spa_writeable(zio->io_spa) &&
|
|
(unexpected_errors > 0 || (zio->io_flags & ZIO_FLAG_RESILVER))) {
|
|
/*
|
|
* Use the good data we have in hand to repair damaged children.
|
|
*/
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
vdev_t *vd = zio->io_vd;
|
|
vdev_t *cvd = vd->vdev_child[rc->rc_devidx];
|
|
|
|
if (!rc->rc_allow_repair) {
|
|
continue;
|
|
} else if (!rc->rc_force_repair &&
|
|
(rc->rc_error == 0 || rc->rc_size == 0)) {
|
|
continue;
|
|
}
|
|
|
|
zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
|
|
rc->rc_offset, rc->rc_abd, rc->rc_size,
|
|
ZIO_TYPE_WRITE,
|
|
zio->io_priority == ZIO_PRIORITY_REBUILD ?
|
|
ZIO_PRIORITY_REBUILD : ZIO_PRIORITY_ASYNC_WRITE,
|
|
ZIO_FLAG_IO_REPAIR | (unexpected_errors ?
|
|
ZIO_FLAG_SELF_HEAL : 0), NULL, NULL));
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
raidz_restore_orig_data(raidz_map_t *rm)
|
|
{
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_need_orig_restore) {
|
|
abd_copy(rc->rc_abd,
|
|
rc->rc_orig_data, rc->rc_size);
|
|
rc->rc_need_orig_restore = B_FALSE;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* returns EINVAL if reconstruction of the block will not be possible
|
|
* returns ECKSUM if this specific reconstruction failed
|
|
* returns 0 on successful reconstruction
|
|
*/
|
|
static int
|
|
raidz_reconstruct(zio_t *zio, int *ltgts, int ntgts, int nparity)
|
|
{
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
/* Reconstruct each row */
|
|
for (int r = 0; r < rm->rm_nrows; r++) {
|
|
raidz_row_t *rr = rm->rm_row[r];
|
|
int my_tgts[VDEV_RAIDZ_MAXPARITY]; /* value is child id */
|
|
int t = 0;
|
|
int dead = 0;
|
|
int dead_data = 0;
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
ASSERT0(rc->rc_need_orig_restore);
|
|
if (rc->rc_error != 0) {
|
|
dead++;
|
|
if (c >= nparity)
|
|
dead_data++;
|
|
continue;
|
|
}
|
|
if (rc->rc_size == 0)
|
|
continue;
|
|
for (int lt = 0; lt < ntgts; lt++) {
|
|
if (rc->rc_devidx == ltgts[lt]) {
|
|
if (rc->rc_orig_data == NULL) {
|
|
rc->rc_orig_data =
|
|
abd_alloc_linear(
|
|
rc->rc_size, B_TRUE);
|
|
abd_copy(rc->rc_orig_data,
|
|
rc->rc_abd, rc->rc_size);
|
|
}
|
|
rc->rc_need_orig_restore = B_TRUE;
|
|
|
|
dead++;
|
|
if (c >= nparity)
|
|
dead_data++;
|
|
my_tgts[t++] = c;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (dead > nparity) {
|
|
/* reconstruction not possible */
|
|
raidz_restore_orig_data(rm);
|
|
return (EINVAL);
|
|
}
|
|
if (dead_data > 0)
|
|
vdev_raidz_reconstruct_row(rm, rr, my_tgts, t);
|
|
}
|
|
|
|
/* Check for success */
|
|
if (raidz_checksum_verify(zio) == 0) {
|
|
|
|
/* Reconstruction succeeded - report errors */
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_need_orig_restore) {
|
|
/*
|
|
* Note: if this is a parity column,
|
|
* we don't really know if it's wrong.
|
|
* We need to let
|
|
* vdev_raidz_io_done_verified() check
|
|
* it, and if we set rc_error, it will
|
|
* think that it is a "known" error
|
|
* that doesn't need to be checked
|
|
* or corrected.
|
|
*/
|
|
if (rc->rc_error == 0 &&
|
|
c >= rr->rr_firstdatacol) {
|
|
raidz_checksum_error(zio,
|
|
rc, rc->rc_orig_data);
|
|
rc->rc_error =
|
|
SET_ERROR(ECKSUM);
|
|
}
|
|
rc->rc_need_orig_restore = B_FALSE;
|
|
}
|
|
}
|
|
|
|
vdev_raidz_io_done_verified(zio, rr);
|
|
}
|
|
|
|
zio_checksum_verified(zio);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* Reconstruction failed - restore original data */
|
|
raidz_restore_orig_data(rm);
|
|
return (ECKSUM);
|
|
}
|
|
|
|
/*
|
|
* Iterate over all combinations of N bad vdevs and attempt a reconstruction.
|
|
* Note that the algorithm below is non-optimal because it doesn't take into
|
|
* account how reconstruction is actually performed. For example, with
|
|
* triple-parity RAID-Z the reconstruction procedure is the same if column 4
|
|
* is targeted as invalid as if columns 1 and 4 are targeted since in both
|
|
* cases we'd only use parity information in column 0.
|
|
*
|
|
* The order that we find the various possible combinations of failed
|
|
* disks is dictated by these rules:
|
|
* - Examine each "slot" (the "i" in tgts[i])
|
|
* - Try to increment this slot (tgts[i] = tgts[i] + 1)
|
|
* - if we can't increment because it runs into the next slot,
|
|
* reset our slot to the minimum, and examine the next slot
|
|
*
|
|
* For example, with a 6-wide RAIDZ3, and no known errors (so we have to choose
|
|
* 3 columns to reconstruct), we will generate the following sequence:
|
|
*
|
|
* STATE ACTION
|
|
* 0 1 2 special case: skip since these are all parity
|
|
* 0 1 3 first slot: reset to 0; middle slot: increment to 2
|
|
* 0 2 3 first slot: increment to 1
|
|
* 1 2 3 first: reset to 0; middle: reset to 1; last: increment to 4
|
|
* 0 1 4 first: reset to 0; middle: increment to 2
|
|
* 0 2 4 first: increment to 1
|
|
* 1 2 4 first: reset to 0; middle: increment to 3
|
|
* 0 3 4 first: increment to 1
|
|
* 1 3 4 first: increment to 2
|
|
* 2 3 4 first: reset to 0; middle: reset to 1; last: increment to 5
|
|
* 0 1 5 first: reset to 0; middle: increment to 2
|
|
* 0 2 5 first: increment to 1
|
|
* 1 2 5 first: reset to 0; middle: increment to 3
|
|
* 0 3 5 first: increment to 1
|
|
* 1 3 5 first: increment to 2
|
|
* 2 3 5 first: reset to 0; middle: increment to 4
|
|
* 0 4 5 first: increment to 1
|
|
* 1 4 5 first: increment to 2
|
|
* 2 4 5 first: increment to 3
|
|
* 3 4 5 done
|
|
*
|
|
* This strategy works for dRAID but is less efficient when there are a large
|
|
* number of child vdevs and therefore permutations to check. Furthermore,
|
|
* since the raidz_map_t rows likely do not overlap reconstruction would be
|
|
* possible as long as there are no more than nparity data errors per row.
|
|
* These additional permutations are not currently checked but could be as
|
|
* a future improvement.
|
|
*/
|
|
static int
|
|
vdev_raidz_combrec(zio_t *zio)
|
|
{
|
|
int nparity = vdev_get_nparity(zio->io_vd);
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
/* Check if there's enough data to attempt reconstrution. */
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
int total_errors = 0;
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
if (rr->rr_col[c].rc_error)
|
|
total_errors++;
|
|
}
|
|
|
|
if (total_errors > nparity)
|
|
return (vdev_raidz_worst_error(rr));
|
|
}
|
|
|
|
for (int num_failures = 1; num_failures <= nparity; num_failures++) {
|
|
int tstore[VDEV_RAIDZ_MAXPARITY + 2];
|
|
int *ltgts = &tstore[1]; /* value is logical child ID */
|
|
|
|
/* Determine number of logical children, n */
|
|
int n = zio->io_vd->vdev_children;
|
|
|
|
ASSERT3U(num_failures, <=, nparity);
|
|
ASSERT3U(num_failures, <=, VDEV_RAIDZ_MAXPARITY);
|
|
|
|
/* Handle corner cases in combrec logic */
|
|
ltgts[-1] = -1;
|
|
for (int i = 0; i < num_failures; i++) {
|
|
ltgts[i] = i;
|
|
}
|
|
ltgts[num_failures] = n;
|
|
|
|
for (;;) {
|
|
int err = raidz_reconstruct(zio, ltgts, num_failures,
|
|
nparity);
|
|
if (err == EINVAL) {
|
|
/*
|
|
* Reconstruction not possible with this #
|
|
* failures; try more failures.
|
|
*/
|
|
break;
|
|
} else if (err == 0)
|
|
return (0);
|
|
|
|
/* Compute next targets to try */
|
|
for (int t = 0; ; t++) {
|
|
ASSERT3U(t, <, num_failures);
|
|
ltgts[t]++;
|
|
if (ltgts[t] == n) {
|
|
/* try more failures */
|
|
ASSERT3U(t, ==, num_failures - 1);
|
|
break;
|
|
}
|
|
|
|
ASSERT3U(ltgts[t], <, n);
|
|
ASSERT3U(ltgts[t], <=, ltgts[t + 1]);
|
|
|
|
/*
|
|
* If that spot is available, we're done here.
|
|
* Try the next combination.
|
|
*/
|
|
if (ltgts[t] != ltgts[t + 1])
|
|
break;
|
|
|
|
/*
|
|
* Otherwise, reset this tgt to the minimum,
|
|
* and move on to the next tgt.
|
|
*/
|
|
ltgts[t] = ltgts[t - 1] + 1;
|
|
ASSERT3U(ltgts[t], ==, t);
|
|
}
|
|
|
|
/* Increase the number of failures and keep trying. */
|
|
if (ltgts[num_failures - 1] == n)
|
|
break;
|
|
}
|
|
}
|
|
|
|
return (ECKSUM);
|
|
}
|
|
|
|
void
|
|
vdev_raidz_reconstruct(raidz_map_t *rm, const int *t, int nt)
|
|
{
|
|
for (uint64_t row = 0; row < rm->rm_nrows; row++) {
|
|
raidz_row_t *rr = rm->rm_row[row];
|
|
vdev_raidz_reconstruct_row(rm, rr, t, nt);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Complete a write IO operation on a RAIDZ VDev
|
|
*
|
|
* Outline:
|
|
* 1. Check for errors on the child IOs.
|
|
* 2. Return, setting an error code if too few child VDevs were written
|
|
* to reconstruct the data later. Note that partial writes are
|
|
* considered successful if they can be reconstructed at all.
|
|
*/
|
|
static void
|
|
vdev_raidz_io_done_write_impl(zio_t *zio, raidz_row_t *rr)
|
|
{
|
|
int total_errors = 0;
|
|
|
|
ASSERT3U(rr->rr_missingparity, <=, rr->rr_firstdatacol);
|
|
ASSERT3U(rr->rr_missingdata, <=, rr->rr_cols - rr->rr_firstdatacol);
|
|
ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE);
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
|
|
if (rc->rc_error) {
|
|
ASSERT(rc->rc_error != ECKSUM); /* child has no bp */
|
|
|
|
total_errors++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Treat partial writes as a success. If we couldn't write enough
|
|
* columns to reconstruct the data, the I/O failed. Otherwise,
|
|
* good enough.
|
|
*
|
|
* Now that we support write reallocation, it would be better
|
|
* to treat partial failure as real failure unless there are
|
|
* no non-degraded top-level vdevs left, and not update DTLs
|
|
* if we intend to reallocate.
|
|
*/
|
|
if (total_errors > rr->rr_firstdatacol) {
|
|
zio->io_error = zio_worst_error(zio->io_error,
|
|
vdev_raidz_worst_error(rr));
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_io_done_reconstruct_known_missing(zio_t *zio, raidz_map_t *rm,
|
|
raidz_row_t *rr)
|
|
{
|
|
int parity_errors = 0;
|
|
int parity_untried = 0;
|
|
int data_errors = 0;
|
|
int total_errors = 0;
|
|
|
|
ASSERT3U(rr->rr_missingparity, <=, rr->rr_firstdatacol);
|
|
ASSERT3U(rr->rr_missingdata, <=, rr->rr_cols - rr->rr_firstdatacol);
|
|
ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ);
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
|
|
if (rc->rc_error) {
|
|
ASSERT(rc->rc_error != ECKSUM); /* child has no bp */
|
|
|
|
if (c < rr->rr_firstdatacol)
|
|
parity_errors++;
|
|
else
|
|
data_errors++;
|
|
|
|
total_errors++;
|
|
} else if (c < rr->rr_firstdatacol && !rc->rc_tried) {
|
|
parity_untried++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If there were data errors and the number of errors we saw was
|
|
* correctable -- less than or equal to the number of parity disks read
|
|
* -- reconstruct based on the missing data.
|
|
*/
|
|
if (data_errors != 0 &&
|
|
total_errors <= rr->rr_firstdatacol - parity_untried) {
|
|
/*
|
|
* We either attempt to read all the parity columns or
|
|
* none of them. If we didn't try to read parity, we
|
|
* wouldn't be here in the correctable case. There must
|
|
* also have been fewer parity errors than parity
|
|
* columns or, again, we wouldn't be in this code path.
|
|
*/
|
|
ASSERT(parity_untried == 0);
|
|
ASSERT(parity_errors < rr->rr_firstdatacol);
|
|
|
|
/*
|
|
* Identify the data columns that reported an error.
|
|
*/
|
|
int n = 0;
|
|
int tgts[VDEV_RAIDZ_MAXPARITY];
|
|
for (int c = rr->rr_firstdatacol; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_error != 0) {
|
|
ASSERT(n < VDEV_RAIDZ_MAXPARITY);
|
|
tgts[n++] = c;
|
|
}
|
|
}
|
|
|
|
ASSERT(rr->rr_firstdatacol >= n);
|
|
|
|
vdev_raidz_reconstruct_row(rm, rr, tgts, n);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return the number of reads issued.
|
|
*/
|
|
static int
|
|
vdev_raidz_read_all(zio_t *zio, raidz_row_t *rr)
|
|
{
|
|
vdev_t *vd = zio->io_vd;
|
|
int nread = 0;
|
|
|
|
rr->rr_missingdata = 0;
|
|
rr->rr_missingparity = 0;
|
|
|
|
/*
|
|
* If this rows contains empty sectors which are not required
|
|
* for a normal read then allocate an ABD for them now so they
|
|
* may be read, verified, and any needed repairs performed.
|
|
*/
|
|
if (rr->rr_nempty && rr->rr_abd_empty == NULL)
|
|
vdev_draid_map_alloc_empty(zio, rr);
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
if (rc->rc_tried || rc->rc_size == 0)
|
|
continue;
|
|
|
|
zio_nowait(zio_vdev_child_io(zio, NULL,
|
|
vd->vdev_child[rc->rc_devidx],
|
|
rc->rc_offset, rc->rc_abd, rc->rc_size,
|
|
zio->io_type, zio->io_priority, 0,
|
|
vdev_raidz_child_done, rc));
|
|
nread++;
|
|
}
|
|
return (nread);
|
|
}
|
|
|
|
/*
|
|
* We're here because either there were too many errors to even attempt
|
|
* reconstruction (total_errors == rm_first_datacol), or vdev_*_combrec()
|
|
* failed. In either case, there is enough bad data to prevent reconstruction.
|
|
* Start checksum ereports for all children which haven't failed.
|
|
*/
|
|
static void
|
|
vdev_raidz_io_done_unrecoverable(zio_t *zio)
|
|
{
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
|
|
for (int c = 0; c < rr->rr_cols; c++) {
|
|
raidz_col_t *rc = &rr->rr_col[c];
|
|
vdev_t *cvd = zio->io_vd->vdev_child[rc->rc_devidx];
|
|
|
|
if (rc->rc_error != 0)
|
|
continue;
|
|
|
|
zio_bad_cksum_t zbc;
|
|
zbc.zbc_has_cksum = 0;
|
|
zbc.zbc_injected = rm->rm_ecksuminjected;
|
|
|
|
(void) zfs_ereport_start_checksum(zio->io_spa,
|
|
cvd, &zio->io_bookmark, zio, rc->rc_offset,
|
|
rc->rc_size, &zbc);
|
|
mutex_enter(&cvd->vdev_stat_lock);
|
|
cvd->vdev_stat.vs_checksum_errors++;
|
|
mutex_exit(&cvd->vdev_stat_lock);
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
vdev_raidz_io_done(zio_t *zio)
|
|
{
|
|
raidz_map_t *rm = zio->io_vsd;
|
|
|
|
if (zio->io_type == ZIO_TYPE_WRITE) {
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
vdev_raidz_io_done_write_impl(zio, rm->rm_row[i]);
|
|
}
|
|
} else {
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
vdev_raidz_io_done_reconstruct_known_missing(zio,
|
|
rm, rr);
|
|
}
|
|
|
|
if (raidz_checksum_verify(zio) == 0) {
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
raidz_row_t *rr = rm->rm_row[i];
|
|
vdev_raidz_io_done_verified(zio, rr);
|
|
}
|
|
zio_checksum_verified(zio);
|
|
} else {
|
|
/*
|
|
* A sequential resilver has no checksum which makes
|
|
* combinatoral reconstruction impossible. This code
|
|
* path is unreachable since raidz_checksum_verify()
|
|
* has no checksum to verify and must succeed.
|
|
*/
|
|
ASSERT3U(zio->io_priority, !=, ZIO_PRIORITY_REBUILD);
|
|
|
|
/*
|
|
* This isn't a typical situation -- either we got a
|
|
* read error or a child silently returned bad data.
|
|
* Read every block so we can try again with as much
|
|
* data and parity as we can track down. If we've
|
|
* already been through once before, all children will
|
|
* be marked as tried so we'll proceed to combinatorial
|
|
* reconstruction.
|
|
*/
|
|
int nread = 0;
|
|
for (int i = 0; i < rm->rm_nrows; i++) {
|
|
nread += vdev_raidz_read_all(zio,
|
|
rm->rm_row[i]);
|
|
}
|
|
if (nread != 0) {
|
|
/*
|
|
* Normally our stage is VDEV_IO_DONE, but if
|
|
* we've already called redone(), it will have
|
|
* changed to VDEV_IO_START, in which case we
|
|
* don't want to call redone() again.
|
|
*/
|
|
if (zio->io_stage != ZIO_STAGE_VDEV_IO_START)
|
|
zio_vdev_io_redone(zio);
|
|
return;
|
|
}
|
|
|
|
zio->io_error = vdev_raidz_combrec(zio);
|
|
if (zio->io_error == ECKSUM &&
|
|
!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
|
|
vdev_raidz_io_done_unrecoverable(zio);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_state_change(vdev_t *vd, int faulted, int degraded)
|
|
{
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
if (faulted > vdrz->vd_nparity)
|
|
vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
|
|
VDEV_AUX_NO_REPLICAS);
|
|
else if (degraded + faulted != 0)
|
|
vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE);
|
|
else
|
|
vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE);
|
|
}
|
|
|
|
/*
|
|
* Determine if any portion of the provided block resides on a child vdev
|
|
* with a dirty DTL and therefore needs to be resilvered. The function
|
|
* assumes that at least one DTL is dirty which implies that full stripe
|
|
* width blocks must be resilvered.
|
|
*/
|
|
static boolean_t
|
|
vdev_raidz_need_resilver(vdev_t *vd, const dva_t *dva, size_t psize,
|
|
uint64_t phys_birth)
|
|
{
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
uint64_t dcols = vd->vdev_children;
|
|
uint64_t nparity = vdrz->vd_nparity;
|
|
uint64_t ashift = vd->vdev_top->vdev_ashift;
|
|
/* The starting RAIDZ (parent) vdev sector of the block. */
|
|
uint64_t b = DVA_GET_OFFSET(dva) >> ashift;
|
|
/* The zio's size in units of the vdev's minimum sector size. */
|
|
uint64_t s = ((psize - 1) >> ashift) + 1;
|
|
/* The first column for this stripe. */
|
|
uint64_t f = b % dcols;
|
|
|
|
/* Unreachable by sequential resilver. */
|
|
ASSERT3U(phys_birth, !=, TXG_UNKNOWN);
|
|
|
|
if (!vdev_dtl_contains(vd, DTL_PARTIAL, phys_birth, 1))
|
|
return (B_FALSE);
|
|
|
|
if (s + nparity >= dcols)
|
|
return (B_TRUE);
|
|
|
|
for (uint64_t c = 0; c < s + nparity; c++) {
|
|
uint64_t devidx = (f + c) % dcols;
|
|
vdev_t *cvd = vd->vdev_child[devidx];
|
|
|
|
/*
|
|
* dsl_scan_need_resilver() already checked vd with
|
|
* vdev_dtl_contains(). So here just check cvd with
|
|
* vdev_dtl_empty(), cheaper and a good approximation.
|
|
*/
|
|
if (!vdev_dtl_empty(cvd, DTL_PARTIAL))
|
|
return (B_TRUE);
|
|
}
|
|
|
|
return (B_FALSE);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_xlate(vdev_t *cvd, const range_seg64_t *logical_rs,
|
|
range_seg64_t *physical_rs, range_seg64_t *remain_rs)
|
|
{
|
|
vdev_t *raidvd = cvd->vdev_parent;
|
|
ASSERT(raidvd->vdev_ops == &vdev_raidz_ops);
|
|
|
|
uint64_t width = raidvd->vdev_children;
|
|
uint64_t tgt_col = cvd->vdev_id;
|
|
uint64_t ashift = raidvd->vdev_top->vdev_ashift;
|
|
|
|
/* make sure the offsets are block-aligned */
|
|
ASSERT0(logical_rs->rs_start % (1 << ashift));
|
|
ASSERT0(logical_rs->rs_end % (1 << ashift));
|
|
uint64_t b_start = logical_rs->rs_start >> ashift;
|
|
uint64_t b_end = logical_rs->rs_end >> ashift;
|
|
|
|
uint64_t start_row = 0;
|
|
if (b_start > tgt_col) /* avoid underflow */
|
|
start_row = ((b_start - tgt_col - 1) / width) + 1;
|
|
|
|
uint64_t end_row = 0;
|
|
if (b_end > tgt_col)
|
|
end_row = ((b_end - tgt_col - 1) / width) + 1;
|
|
|
|
physical_rs->rs_start = start_row << ashift;
|
|
physical_rs->rs_end = end_row << ashift;
|
|
|
|
ASSERT3U(physical_rs->rs_start, <=, logical_rs->rs_start);
|
|
ASSERT3U(physical_rs->rs_end - physical_rs->rs_start, <=,
|
|
logical_rs->rs_end - logical_rs->rs_start);
|
|
}
|
|
|
|
/*
|
|
* Initialize private RAIDZ specific fields from the nvlist.
|
|
*/
|
|
static int
|
|
vdev_raidz_init(spa_t *spa, nvlist_t *nv, void **tsd)
|
|
{
|
|
vdev_raidz_t *vdrz;
|
|
uint64_t nparity;
|
|
|
|
uint_t children;
|
|
nvlist_t **child;
|
|
int error = nvlist_lookup_nvlist_array(nv,
|
|
ZPOOL_CONFIG_CHILDREN, &child, &children);
|
|
if (error != 0)
|
|
return (SET_ERROR(EINVAL));
|
|
|
|
if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_NPARITY, &nparity) == 0) {
|
|
if (nparity == 0 || nparity > VDEV_RAIDZ_MAXPARITY)
|
|
return (SET_ERROR(EINVAL));
|
|
|
|
/*
|
|
* Previous versions could only support 1 or 2 parity
|
|
* device.
|
|
*/
|
|
if (nparity > 1 && spa_version(spa) < SPA_VERSION_RAIDZ2)
|
|
return (SET_ERROR(EINVAL));
|
|
else if (nparity > 2 && spa_version(spa) < SPA_VERSION_RAIDZ3)
|
|
return (SET_ERROR(EINVAL));
|
|
} else {
|
|
/*
|
|
* We require the parity to be specified for SPAs that
|
|
* support multiple parity levels.
|
|
*/
|
|
if (spa_version(spa) >= SPA_VERSION_RAIDZ2)
|
|
return (SET_ERROR(EINVAL));
|
|
|
|
/*
|
|
* Otherwise, we default to 1 parity device for RAID-Z.
|
|
*/
|
|
nparity = 1;
|
|
}
|
|
|
|
vdrz = kmem_zalloc(sizeof (*vdrz), KM_SLEEP);
|
|
vdrz->vd_logical_width = children;
|
|
vdrz->vd_nparity = nparity;
|
|
|
|
*tsd = vdrz;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
vdev_raidz_fini(vdev_t *vd)
|
|
{
|
|
kmem_free(vd->vdev_tsd, sizeof (vdev_raidz_t));
|
|
}
|
|
|
|
/*
|
|
* Add RAIDZ specific fields to the config nvlist.
|
|
*/
|
|
static void
|
|
vdev_raidz_config_generate(vdev_t *vd, nvlist_t *nv)
|
|
{
|
|
ASSERT3P(vd->vdev_ops, ==, &vdev_raidz_ops);
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
|
|
/*
|
|
* Make sure someone hasn't managed to sneak a fancy new vdev
|
|
* into a crufty old storage pool.
|
|
*/
|
|
ASSERT(vdrz->vd_nparity == 1 ||
|
|
(vdrz->vd_nparity <= 2 &&
|
|
spa_version(vd->vdev_spa) >= SPA_VERSION_RAIDZ2) ||
|
|
(vdrz->vd_nparity <= 3 &&
|
|
spa_version(vd->vdev_spa) >= SPA_VERSION_RAIDZ3));
|
|
|
|
/*
|
|
* Note that we'll add these even on storage pools where they
|
|
* aren't strictly required -- older software will just ignore
|
|
* it.
|
|
*/
|
|
fnvlist_add_uint64(nv, ZPOOL_CONFIG_NPARITY, vdrz->vd_nparity);
|
|
}
|
|
|
|
static uint64_t
|
|
vdev_raidz_nparity(vdev_t *vd)
|
|
{
|
|
vdev_raidz_t *vdrz = vd->vdev_tsd;
|
|
return (vdrz->vd_nparity);
|
|
}
|
|
|
|
static uint64_t
|
|
vdev_raidz_ndisks(vdev_t *vd)
|
|
{
|
|
return (vd->vdev_children);
|
|
}
|
|
|
|
vdev_ops_t vdev_raidz_ops = {
|
|
.vdev_op_init = vdev_raidz_init,
|
|
.vdev_op_fini = vdev_raidz_fini,
|
|
.vdev_op_open = vdev_raidz_open,
|
|
.vdev_op_close = vdev_raidz_close,
|
|
.vdev_op_asize = vdev_raidz_asize,
|
|
.vdev_op_min_asize = vdev_raidz_min_asize,
|
|
.vdev_op_min_alloc = NULL,
|
|
.vdev_op_io_start = vdev_raidz_io_start,
|
|
.vdev_op_io_done = vdev_raidz_io_done,
|
|
.vdev_op_state_change = vdev_raidz_state_change,
|
|
.vdev_op_need_resilver = vdev_raidz_need_resilver,
|
|
.vdev_op_hold = NULL,
|
|
.vdev_op_rele = NULL,
|
|
.vdev_op_remap = NULL,
|
|
.vdev_op_xlate = vdev_raidz_xlate,
|
|
.vdev_op_rebuild_asize = NULL,
|
|
.vdev_op_metaslab_init = NULL,
|
|
.vdev_op_config_generate = vdev_raidz_config_generate,
|
|
.vdev_op_nparity = vdev_raidz_nparity,
|
|
.vdev_op_ndisks = vdev_raidz_ndisks,
|
|
.vdev_op_type = VDEV_TYPE_RAIDZ, /* name of this vdev type */
|
|
.vdev_op_leaf = B_FALSE /* not a leaf vdev */
|
|
};
|