*/
/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
/*
* Virtual device vector for RAID-Z.
*
- * This vdev supports both single and double parity. For single parity, we
- * use a simple XOR of all the data columns. For double parity, we use both
- * the simple XOR as well as a technique described in "The mathematics of
- * RAID-6" by H. Peter Anvin. This technique defines a Galois field, GF(2^8),
- * over the integers expressable in a single byte. Briefly, the operations on
- * the field are defined as follows:
+ * This vdev supports single, double, and triple parity. For single parity,
+ * we use a simple XOR of all the data columns. For double or triple parity,
+ * we use a special case of Reed-Solomon coding. This extends the
+ * technique described in "The mathematics of RAID-6" by H. Peter Anvin by
+ * drawing on the system described in "A Tutorial on Reed-Solomon Coding for
+ * Fault-Tolerance in RAID-like Systems" by James S. Plank on which the
+ * former is also based. The latter is designed to provide higher performance
+ * for writes.
+ *
+ * Note that the Plank paper claimed to support arbitrary N+M, but was then
+ * amended six years later identifying a critical flaw that invalidates its
+ * claims. Nevertheless, the technique can be adapted to work for up to
+ * triple parity. For additional parity, the amendment "Note: Correction to
+ * the 1997 Tutorial on Reed-Solomon Coding" by James S. Plank and Ying Ding
+ * is viable, but the additional complexity means that write performance will
+ * suffer.
+ *
+ * All of the methods above operate on a Galois field, defined over the
+ * integers mod 2^N. In our case we choose N=8 for GF(8) so that all elements
+ * can be expressed with a single byte. Briefly, the operations on the
+ * field are defined as follows:
*
* o addition (+) is represented by a bitwise XOR
* o subtraction (-) is therefore identical to addition: A + B = A - B
* (A * 2)_0 = A_7
*
* In C, multiplying by 2 is therefore ((a << 1) ^ ((a & 0x80) ? 0x1d : 0)).
+ * As an aside, this multiplication is derived from the error correcting
+ * primitive polynomial x^8 + x^4 + x^3 + x^2 + 1.
*
* Observe that any number in the field (except for 0) can be expressed as a
* power of 2 -- a generator for the field. We store a table of the powers of
* 2 and logs base 2 for quick look ups, and exploit the fact that A * B can
* be rewritten as 2^(log_2(A) + log_2(B)) (where '+' is normal addition rather
- * than field addition). The inverse of a field element A (A^-1) is A^254.
+ * than field addition). The inverse of a field element A (A^-1) is therefore
+ * A ^ (255 - 1) = A^254.
*
- * The two parity columns, P and Q, over several data columns, D_0, ... D_n-1,
- * can be expressed by field operations:
+ * The up-to-three parity columns, P, Q, R over several data columns,
+ * D_0, ... D_n-1, can be expressed by field operations:
*
* P = D_0 + D_1 + ... + D_n-2 + D_n-1
* Q = 2^n-1 * D_0 + 2^n-2 * D_1 + ... + 2^1 * D_n-2 + 2^0 * D_n-1
* = ((...((D_0) * 2 + D_1) * 2 + ...) * 2 + D_n-2) * 2 + D_n-1
+ * R = 4^n-1 * D_0 + 4^n-2 * D_1 + ... + 4^1 * D_n-2 + 4^0 * D_n-1
+ * = ((...((D_0) * 4 + D_1) * 4 + ...) * 4 + D_n-2) * 4 + D_n-1
*
- * See the reconstruction code below for how P and Q can used individually or
- * in concert to recover missing data columns.
+ * We chose 1, 2, and 4 as our generators because 1 corresponds to the trival
+ * XOR operation, and 2 and 4 can be computed quickly and generate linearly-
+ * independent coefficients. (There are no additional coefficients that have
+ * this property which is why the uncorrected Plank method breaks down.)
+ *
+ * See the reconstruction code below for how P, Q and R can used individually
+ * or in concert to recover missing data columns.
*/
typedef struct raidz_col {
uint64_t rc_offset; /* device offset */
uint64_t rc_size; /* I/O size */
void *rc_data; /* I/O data */
+ void *rc_gdata; /* used to store the "good" version */
int rc_error; /* I/O error for this device */
uint8_t rc_tried; /* Did we attempt this I/O column? */
uint8_t rc_skipped; /* Did we skip this I/O column? */
} raidz_col_t;
typedef struct raidz_map {
- uint64_t rm_cols; /* Column count */
+ uint64_t rm_cols; /* Regular column count */
+ uint64_t rm_scols; /* Count including skipped columns */
uint64_t rm_bigcols; /* Number of oversized columns */
uint64_t rm_asize; /* Actual total I/O size */
uint64_t rm_missingdata; /* Count of missing data devices */
uint64_t rm_missingparity; /* Count of missing parity devices */
uint64_t rm_firstdatacol; /* First data column/parity count */
+ uint64_t rm_nskip; /* Skipped sectors for padding */
+ uint64_t rm_skipstart; /* Column index of padding start */
+ void *rm_datacopy; /* rm_asize-buffer of copied data */
+ uintptr_t rm_reports; /* # of referencing checksum reports */
+ uint8_t rm_freed; /* map no longer has referencing ZIO */
+ uint8_t rm_ecksuminjected; /* checksum error was injected */
raidz_col_t rm_col[1]; /* Flexible array of I/O columns */
} raidz_map_t;
#define VDEV_RAIDZ_P 0
#define VDEV_RAIDZ_Q 1
+#define VDEV_RAIDZ_R 2
+
+#define VDEV_RAIDZ_MUL_2(x) (((x) << 1) ^ (((x) & 0x80) ? 0x1d : 0))
+#define VDEV_RAIDZ_MUL_4(x) (VDEV_RAIDZ_MUL_2(VDEV_RAIDZ_MUL_2(x)))
+
+/*
+ * We provide a mechanism to perform the field multiplication operation on a
+ * 64-bit value all at once rather than a byte at a time. This works by
+ * creating a mask from the top bit in each byte and using that to
+ * conditionally apply the XOR of 0x1d.
+ */
+#define VDEV_RAIDZ_64MUL_2(x, mask) \
+{ \
+ (mask) = (x) & 0x8080808080808080ULL; \
+ (mask) = ((mask) << 1) - ((mask) >> 7); \
+ (x) = (((x) << 1) & 0xfefefefefefefefeULL) ^ \
+ ((mask) & 0x1d1d1d1d1d1d1d1dULL); \
+}
-#define VDEV_RAIDZ_MAXPARITY 2
+#define VDEV_RAIDZ_64MUL_4(x, mask) \
+{ \
+ VDEV_RAIDZ_64MUL_2((x), mask); \
+ VDEV_RAIDZ_64MUL_2((x), mask); \
+}
-#define VDEV_RAIDZ_MUL_2(a) (((a) << 1) ^ (((a) & 0x80) ? 0x1d : 0))
+/*
+ * Force reconstruction to use the general purpose method.
+ */
+int vdev_raidz_default_to_general;
/*
* These two tables represent powers and logs of 2 in the Galois field defined
0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf,
};
+static void vdev_raidz_generate_parity(raidz_map_t *rm);
+
/*
* Multiply a given number by 2 raised to the given power.
*/
}
static void
-vdev_raidz_map_free(zio_t *zio)
+vdev_raidz_map_free(raidz_map_t *rm)
{
- raidz_map_t *rm = zio->io_vsd;
int c;
+ size_t size;
- for (c = 0; c < rm->rm_firstdatacol; c++)
+ for (c = 0; c < rm->rm_firstdatacol; c++) {
zio_buf_free(rm->rm_col[c].rc_data, rm->rm_col[c].rc_size);
- kmem_free(rm, offsetof(raidz_map_t, rm_col[rm->rm_cols]));
+ if (rm->rm_col[c].rc_gdata != NULL)
+ zio_buf_free(rm->rm_col[c].rc_gdata,
+ rm->rm_col[c].rc_size);
+ }
+
+ size = 0;
+ for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++)
+ size += rm->rm_col[c].rc_size;
+
+ if (rm->rm_datacopy != NULL)
+ zio_buf_free(rm->rm_datacopy, size);
+
+ kmem_free(rm, offsetof(raidz_map_t, rm_col[rm->rm_scols]));
+}
+
+static void
+vdev_raidz_map_free_vsd(zio_t *zio)
+{
+ raidz_map_t *rm = zio->io_vsd;
+
+ ASSERT0(rm->rm_freed);
+ rm->rm_freed = 1;
+
+ if (rm->rm_reports == 0)
+ vdev_raidz_map_free(rm);
+}
+
+/*ARGSUSED*/
+static void
+vdev_raidz_cksum_free(void *arg, size_t ignored)
+{
+ raidz_map_t *rm = arg;
+
+ ASSERT3U(rm->rm_reports, >, 0);
+
+ if (--rm->rm_reports == 0 && rm->rm_freed != 0)
+ vdev_raidz_map_free(rm);
+}
+
+static void
+vdev_raidz_cksum_finish(zio_cksum_report_t *zcr, const void *good_data)
+{
+ raidz_map_t *rm = zcr->zcr_cbdata;
+ size_t c = zcr->zcr_cbinfo;
+ size_t x;
+
+ const char *good = NULL;
+ const char *bad = rm->rm_col[c].rc_data;
+
+ if (good_data == NULL) {
+ zfs_ereport_finish_checksum(zcr, NULL, NULL, B_FALSE);
+ return;
+ }
+
+ if (c < rm->rm_firstdatacol) {
+ /*
+ * The first time through, calculate the parity blocks for
+ * the good data (this relies on the fact that the good
+ * data never changes for a given logical ZIO)
+ */
+ if (rm->rm_col[0].rc_gdata == NULL) {
+ char *bad_parity[VDEV_RAIDZ_MAXPARITY];
+ char *buf;
+
+ /*
+ * Set up the rm_col[]s to generate the parity for
+ * good_data, first saving the parity bufs and
+ * replacing them with buffers to hold the result.
+ */
+ for (x = 0; x < rm->rm_firstdatacol; x++) {
+ bad_parity[x] = rm->rm_col[x].rc_data;
+ rm->rm_col[x].rc_data = rm->rm_col[x].rc_gdata =
+ zio_buf_alloc(rm->rm_col[x].rc_size);
+ }
+
+ /* fill in the data columns from good_data */
+ buf = (char *)good_data;
+ for (; x < rm->rm_cols; x++) {
+ rm->rm_col[x].rc_data = buf;
+ buf += rm->rm_col[x].rc_size;
+ }
+
+ /*
+ * Construct the parity from the good data.
+ */
+ vdev_raidz_generate_parity(rm);
+
+ /* restore everything back to its original state */
+ for (x = 0; x < rm->rm_firstdatacol; x++)
+ rm->rm_col[x].rc_data = bad_parity[x];
+
+ buf = rm->rm_datacopy;
+ for (x = rm->rm_firstdatacol; x < rm->rm_cols; x++) {
+ rm->rm_col[x].rc_data = buf;
+ buf += rm->rm_col[x].rc_size;
+ }
+ }
+
+ ASSERT3P(rm->rm_col[c].rc_gdata, !=, NULL);
+ good = rm->rm_col[c].rc_gdata;
+ } else {
+ /* adjust good_data to point at the start of our column */
+ good = good_data;
+
+ for (x = rm->rm_firstdatacol; x < c; x++)
+ good += rm->rm_col[x].rc_size;
+ }
+
+ /* we drop the ereport if it ends up that the data was good */
+ zfs_ereport_finish_checksum(zcr, good, bad, B_TRUE);
+}
+
+/*
+ * Invoked indirectly by zfs_ereport_start_checksum(), called
+ * below when our read operation fails completely. The main point
+ * is to keep a copy of everything we read from disk, so that at
+ * vdev_raidz_cksum_finish() time we can compare it with the good data.
+ */
+static void
+vdev_raidz_cksum_report(zio_t *zio, zio_cksum_report_t *zcr, void *arg)
+{
+ size_t c = (size_t)(uintptr_t)arg;
+ caddr_t buf;
+
+ raidz_map_t *rm = zio->io_vsd;
+ size_t size;
+
+ /* set up the report and bump the refcount */
+ zcr->zcr_cbdata = rm;
+ zcr->zcr_cbinfo = c;
+ zcr->zcr_finish = vdev_raidz_cksum_finish;
+ zcr->zcr_free = vdev_raidz_cksum_free;
+
+ rm->rm_reports++;
+ ASSERT3U(rm->rm_reports, >, 0);
+
+ if (rm->rm_datacopy != NULL)
+ return;
+
+ /*
+ * It's the first time we're called for this raidz_map_t, so we need
+ * to copy the data aside; there's no guarantee that our zio's buffer
+ * won't be re-used for something else.
+ *
+ * Our parity data is already in separate buffers, so there's no need
+ * to copy them.
+ */
+
+ size = 0;
+ for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++)
+ size += rm->rm_col[c].rc_size;
+
+ buf = rm->rm_datacopy = zio_buf_alloc(size);
+
+ for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
+ raidz_col_t *col = &rm->rm_col[c];
+
+ bcopy(col->rc_data, buf, col->rc_size);
+ col->rc_data = buf;
+
+ buf += col->rc_size;
+ }
+ ASSERT3P(buf - (caddr_t)rm->rm_datacopy, ==, size);
}
+static const zio_vsd_ops_t vdev_raidz_vsd_ops = {
+ vdev_raidz_map_free_vsd,
+ vdev_raidz_cksum_report
+};
+
static raidz_map_t *
vdev_raidz_map_alloc(zio_t *zio, uint64_t unit_shift, uint64_t dcols,
uint64_t nparity)
uint64_t s = zio->io_size >> unit_shift;
uint64_t f = b % dcols;
uint64_t o = (b / dcols) << unit_shift;
- uint64_t q, r, c, bc, col, acols, coff, devidx;
+ uint64_t q, r, c, bc, col, acols, scols, coff, devidx, asize, tot;
q = s / (dcols - nparity);
r = s - q * (dcols - nparity);
bc = (r == 0 ? 0 : r + nparity);
+ tot = s + nparity * (q + (r == 0 ? 0 : 1));
+
+ if (q == 0) {
+ acols = bc;
+ scols = MIN(dcols, roundup(bc, nparity + 1));
+ } else {
+ acols = dcols;
+ scols = dcols;
+ }
- acols = (q == 0 ? bc : dcols);
+ ASSERT3U(acols, <=, scols);
- rm = kmem_alloc(offsetof(raidz_map_t, rm_col[acols]), KM_SLEEP);
+ rm = kmem_alloc(offsetof(raidz_map_t, rm_col[scols]), KM_PUSHPAGE);
rm->rm_cols = acols;
+ rm->rm_scols = scols;
rm->rm_bigcols = bc;
- rm->rm_asize = 0;
+ rm->rm_skipstart = bc;
rm->rm_missingdata = 0;
rm->rm_missingparity = 0;
rm->rm_firstdatacol = nparity;
+ rm->rm_datacopy = NULL;
+ rm->rm_reports = 0;
+ rm->rm_freed = 0;
+ rm->rm_ecksuminjected = 0;
- for (c = 0; c < acols; c++) {
+ asize = 0;
+
+ for (c = 0; c < scols; c++) {
col = f + c;
coff = o;
if (col >= dcols) {
}
rm->rm_col[c].rc_devidx = col;
rm->rm_col[c].rc_offset = coff;
- rm->rm_col[c].rc_size = (q + (c < bc)) << unit_shift;
rm->rm_col[c].rc_data = NULL;
+ rm->rm_col[c].rc_gdata = NULL;
rm->rm_col[c].rc_error = 0;
rm->rm_col[c].rc_tried = 0;
rm->rm_col[c].rc_skipped = 0;
- rm->rm_asize += rm->rm_col[c].rc_size;
+
+ if (c >= acols)
+ rm->rm_col[c].rc_size = 0;
+ else if (c < bc)
+ rm->rm_col[c].rc_size = (q + 1) << unit_shift;
+ else
+ rm->rm_col[c].rc_size = q << unit_shift;
+
+ asize += rm->rm_col[c].rc_size;
}
- rm->rm_asize = roundup(rm->rm_asize, (nparity + 1) << unit_shift);
+ ASSERT3U(asize, ==, tot << unit_shift);
+ rm->rm_asize = roundup(asize, (nparity + 1) << unit_shift);
+ rm->rm_nskip = roundup(tot, nparity + 1) - tot;
+ ASSERT3U(rm->rm_asize - asize, ==, rm->rm_nskip << unit_shift);
+ ASSERT3U(rm->rm_nskip, <=, nparity);
for (c = 0; c < rm->rm_firstdatacol; c++)
rm->rm_col[c].rc_data = zio_buf_alloc(rm->rm_col[c].rc_size);
* Unfortunately, this decision created an implicit on-disk format
* requirement that we need to support for all eternity, but only
* for single-parity RAID-Z.
+ *
+ * If we intend to skip a sector in the zeroth column for padding
+ * we must make sure to note this swap. We will never intend to
+ * skip the first column since at least one data and one parity
+ * column must appear in each row.
*/
ASSERT(rm->rm_cols >= 2);
ASSERT(rm->rm_col[0].rc_size == rm->rm_col[1].rc_size);
rm->rm_col[0].rc_offset = rm->rm_col[1].rc_offset;
rm->rm_col[1].rc_devidx = devidx;
rm->rm_col[1].rc_offset = o;
+
+ if (rm->rm_skipstart == 0)
+ rm->rm_skipstart = 1;
}
zio->io_vsd = rm;
- zio->io_vsd_free = vdev_raidz_map_free;
+ zio->io_vsd_ops = &vdev_raidz_vsd_ops;
return (rm);
}
if (c == rm->rm_firstdatacol) {
ASSERT(ccount == pcount);
- for (i = 0; i < ccount; i++, p++, src++) {
+ for (i = 0; i < ccount; i++, src++, p++) {
*p = *src;
}
} else {
ASSERT(ccount <= pcount);
- for (i = 0; i < ccount; i++, p++, src++) {
+ for (i = 0; i < ccount; i++, src++, p++) {
*p ^= *src;
}
}
static void
vdev_raidz_generate_parity_pq(raidz_map_t *rm)
{
- uint64_t *q, *p, *src, pcount, ccount, mask, i;
+ uint64_t *p, *q, *src, pcnt, ccnt, mask, i;
int c;
- pcount = rm->rm_col[VDEV_RAIDZ_P].rc_size / sizeof (src[0]);
+ pcnt = rm->rm_col[VDEV_RAIDZ_P].rc_size / sizeof (src[0]);
ASSERT(rm->rm_col[VDEV_RAIDZ_P].rc_size ==
rm->rm_col[VDEV_RAIDZ_Q].rc_size);
src = rm->rm_col[c].rc_data;
p = rm->rm_col[VDEV_RAIDZ_P].rc_data;
q = rm->rm_col[VDEV_RAIDZ_Q].rc_data;
- ccount = rm->rm_col[c].rc_size / sizeof (src[0]);
+
+ ccnt = rm->rm_col[c].rc_size / sizeof (src[0]);
if (c == rm->rm_firstdatacol) {
- ASSERT(ccount == pcount || ccount == 0);
- for (i = 0; i < ccount; i++, p++, q++, src++) {
- *q = *src;
+ ASSERT(ccnt == pcnt || ccnt == 0);
+ for (i = 0; i < ccnt; i++, src++, p++, q++) {
*p = *src;
+ *q = *src;
}
- for (; i < pcount; i++, p++, q++, src++) {
- *q = 0;
+ for (; i < pcnt; i++, src++, p++, q++) {
*p = 0;
+ *q = 0;
}
} else {
- ASSERT(ccount <= pcount);
+ ASSERT(ccnt <= pcnt);
/*
- * Rather than multiplying each byte individually (as
- * described above), we are able to handle 8 at once
- * by generating a mask based on the high bit in each
- * byte and using that to conditionally XOR in 0x1d.
+ * Apply the algorithm described above by multiplying
+ * the previous result and adding in the new value.
*/
- for (i = 0; i < ccount; i++, p++, q++, src++) {
- mask = *q & 0x8080808080808080ULL;
- mask = (mask << 1) - (mask >> 7);
- *q = ((*q << 1) & 0xfefefefefefefefeULL) ^
- (mask & 0x1d1d1d1d1d1d1d1dULL);
+ for (i = 0; i < ccnt; i++, src++, p++, q++) {
+ *p ^= *src;
+
+ VDEV_RAIDZ_64MUL_2(*q, mask);
*q ^= *src;
+ }
+
+ /*
+ * Treat short columns as though they are full of 0s.
+ * Note that there's therefore nothing needed for P.
+ */
+ for (; i < pcnt; i++, q++) {
+ VDEV_RAIDZ_64MUL_2(*q, mask);
+ }
+ }
+ }
+}
+
+static void
+vdev_raidz_generate_parity_pqr(raidz_map_t *rm)
+{
+ uint64_t *p, *q, *r, *src, pcnt, ccnt, mask, i;
+ int c;
+
+ pcnt = rm->rm_col[VDEV_RAIDZ_P].rc_size / sizeof (src[0]);
+ ASSERT(rm->rm_col[VDEV_RAIDZ_P].rc_size ==
+ rm->rm_col[VDEV_RAIDZ_Q].rc_size);
+ ASSERT(rm->rm_col[VDEV_RAIDZ_P].rc_size ==
+ rm->rm_col[VDEV_RAIDZ_R].rc_size);
+
+ for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
+ src = rm->rm_col[c].rc_data;
+ p = rm->rm_col[VDEV_RAIDZ_P].rc_data;
+ q = rm->rm_col[VDEV_RAIDZ_Q].rc_data;
+ r = rm->rm_col[VDEV_RAIDZ_R].rc_data;
+
+ ccnt = rm->rm_col[c].rc_size / sizeof (src[0]);
+
+ if (c == rm->rm_firstdatacol) {
+ ASSERT(ccnt == pcnt || ccnt == 0);
+ for (i = 0; i < ccnt; i++, src++, p++, q++, r++) {
+ *p = *src;
+ *q = *src;
+ *r = *src;
+ }
+ for (; i < pcnt; i++, src++, p++, q++, r++) {
+ *p = 0;
+ *q = 0;
+ *r = 0;
+ }
+ } else {
+ ASSERT(ccnt <= pcnt);
+
+ /*
+ * Apply the algorithm described above by multiplying
+ * the previous result and adding in the new value.
+ */
+ for (i = 0; i < ccnt; i++, src++, p++, q++, r++) {
*p ^= *src;
+
+ VDEV_RAIDZ_64MUL_2(*q, mask);
+ *q ^= *src;
+
+ VDEV_RAIDZ_64MUL_4(*r, mask);
+ *r ^= *src;
}
/*
* Treat short columns as though they are full of 0s.
+ * Note that there's therefore nothing needed for P.
*/
- for (; i < pcount; i++, q++) {
- mask = *q & 0x8080808080808080ULL;
- mask = (mask << 1) - (mask >> 7);
- *q = ((*q << 1) & 0xfefefefefefefefeULL) ^
- (mask & 0x1d1d1d1d1d1d1d1dULL);
+ for (; i < pcnt; i++, q++, r++) {
+ VDEV_RAIDZ_64MUL_2(*q, mask);
+ VDEV_RAIDZ_64MUL_4(*r, mask);
}
}
}
}
+/*
+ * Generate RAID parity in the first virtual columns according to the number of
+ * parity columns available.
+ */
static void
-vdev_raidz_reconstruct_p(raidz_map_t *rm, int x)
+vdev_raidz_generate_parity(raidz_map_t *rm)
+{
+ switch (rm->rm_firstdatacol) {
+ case 1:
+ vdev_raidz_generate_parity_p(rm);
+ break;
+ case 2:
+ vdev_raidz_generate_parity_pq(rm);
+ break;
+ case 3:
+ vdev_raidz_generate_parity_pqr(rm);
+ break;
+ default:
+ cmn_err(CE_PANIC, "invalid RAID-Z configuration");
+ }
+}
+
+static int
+vdev_raidz_reconstruct_p(raidz_map_t *rm, int *tgts, int ntgts)
{
uint64_t *dst, *src, xcount, ccount, count, i;
+ int x = tgts[0];
int c;
+ ASSERT(ntgts == 1);
+ ASSERT(x >= rm->rm_firstdatacol);
+ ASSERT(x < rm->rm_cols);
+
xcount = rm->rm_col[x].rc_size / sizeof (src[0]);
ASSERT(xcount <= rm->rm_col[VDEV_RAIDZ_P].rc_size / sizeof (src[0]));
ASSERT(xcount > 0);
*dst ^= *src;
}
}
+
+ return (1 << VDEV_RAIDZ_P);
}
-static void
-vdev_raidz_reconstruct_q(raidz_map_t *rm, int x)
+static int
+vdev_raidz_reconstruct_q(raidz_map_t *rm, int *tgts, int ntgts)
{
uint64_t *dst, *src, xcount, ccount, count, mask, i;
uint8_t *b;
+ int x = tgts[0];
int c, j, exp;
+ ASSERT(ntgts == 1);
+
xcount = rm->rm_col[x].rc_size / sizeof (src[0]);
ASSERT(xcount <= rm->rm_col[VDEV_RAIDZ_Q].rc_size / sizeof (src[0]));
}
} else {
- /*
- * For an explanation of this, see the comment in
- * vdev_raidz_generate_parity_pq() above.
- */
for (i = 0; i < count; i++, dst++, src++) {
- mask = *dst & 0x8080808080808080ULL;
- mask = (mask << 1) - (mask >> 7);
- *dst = ((*dst << 1) & 0xfefefefefefefefeULL) ^
- (mask & 0x1d1d1d1d1d1d1d1dULL);
+ VDEV_RAIDZ_64MUL_2(*dst, mask);
*dst ^= *src;
}
for (; i < xcount; i++, dst++) {
- mask = *dst & 0x8080808080808080ULL;
- mask = (mask << 1) - (mask >> 7);
- *dst = ((*dst << 1) & 0xfefefefefefefefeULL) ^
- (mask & 0x1d1d1d1d1d1d1d1dULL);
+ VDEV_RAIDZ_64MUL_2(*dst, mask);
}
}
}
*b = vdev_raidz_exp2(*b, exp);
}
}
+
+ return (1 << VDEV_RAIDZ_Q);
}
-static void
-vdev_raidz_reconstruct_pq(raidz_map_t *rm, int x, int y)
+static int
+vdev_raidz_reconstruct_pq(raidz_map_t *rm, int *tgts, int ntgts)
{
uint8_t *p, *q, *pxy, *qxy, *xd, *yd, tmp, a, b, aexp, bexp;
void *pdata, *qdata;
uint64_t xsize, ysize, i;
+ int x = tgts[0];
+ int y = tgts[1];
+ ASSERT(ntgts == 2);
ASSERT(x < y);
ASSERT(x >= rm->rm_firstdatacol);
ASSERT(y < rm->rm_cols);
*/
rm->rm_col[VDEV_RAIDZ_P].rc_data = pdata;
rm->rm_col[VDEV_RAIDZ_Q].rc_data = qdata;
+
+ return ((1 << VDEV_RAIDZ_P) | (1 << VDEV_RAIDZ_Q));
}
+/* BEGIN CSTYLED */
+/*
+ * In the general case of reconstruction, we must solve the system of linear
+ * equations defined by the coeffecients 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 coeffecients 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 int
-vdev_raidz_open(vdev_t *vd, uint64_t *asize, uint64_t *ashift)
+static void
+vdev_raidz_matrix_init(raidz_map_t *rm, int n, int nmap, int *map,
+ uint8_t **rows)
{
- vdev_t *cvd;
- uint64_t nparity = vd->vdev_nparity;
- int c, error;
- int lasterror = 0;
- int numerrors = 0;
+ int i, j;
+ int pow;
- ASSERT(nparity > 0);
+ ASSERT(n == rm->rm_cols - rm->rm_firstdatacol);
- if (nparity > VDEV_RAIDZ_MAXPARITY ||
- vd->vdev_children < nparity + 1) {
- vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
- return (EINVAL);
+ /*
+ * 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];
+ }
}
+}
- for (c = 0; c < vd->vdev_children; c++) {
- cvd = vd->vdev_child[c];
+static void
+vdev_raidz_matrix_invert(raidz_map_t *rm, int n, int nmissing, int *missing,
+ uint8_t **rows, uint8_t **invrows, const uint8_t *used)
+{
+ int i, j, ii, jj;
+ uint8_t log;
- if ((error = vdev_open(cvd)) != 0) {
- lasterror = error;
- numerrors++;
- continue;
+ /*
+ * 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], <, rm->rm_firstdatacol);
+ }
+ for (; i < n; i++) {
+ ASSERT3S(used[i], >=, rm->rm_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;
}
+ }
- *asize = MIN(*asize - 1, cvd->vdev_asize - 1) + 1;
- *ashift = MAX(*ashift, cvd->vdev_ashift);
+ /*
+ * Subtract all trivial rows from the rows of consequence.
+ */
+ for (i = 0; i < nmissing; i++) {
+ for (j = nmissing; j < n; j++) {
+ ASSERT3U(used[j], >=, rm->rm_firstdatacol);
+ jj = used[j] - rm->rm_firstdatacol;
+ ASSERT3S(jj, <, n);
+ invrows[i][j] = rows[i][jj];
+ rows[i][jj] = 0;
+ }
}
- *asize *= vd->vdev_children;
+ /*
+ * 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);
- if (numerrors > nparity) {
- vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
- return (lasterror);
- }
+ /*
+ * 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]]];
- return (0);
-}
+ 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);
+ }
-static void
-vdev_raidz_close(vdev_t *vd)
-{
- int c;
+ for (ii = 0; ii < nmissing; ii++) {
+ if (i == ii)
+ continue;
- for (c = 0; c < vd->vdev_children; c++)
- vdev_close(vd->vdev_child[c]);
-}
+ ASSERT3U(rows[ii][missing[i]], !=, 0);
-static uint64_t
-vdev_raidz_asize(vdev_t *vd, uint64_t psize)
-{
- uint64_t asize;
- uint64_t ashift = vd->vdev_top->vdev_ashift;
- uint64_t cols = vd->vdev_children;
- uint64_t nparity = vd->vdev_nparity;
+ log = vdev_raidz_log2[rows[ii][missing[i]]];
- asize = ((psize - 1) >> ashift) + 1;
- asize += nparity * ((asize + cols - nparity - 1) / (cols - nparity));
- asize = roundup(asize, nparity + 1) << ashift;
+ 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);
+ }
+ }
+ }
- return (asize);
+ /*
+ * 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_child_done(zio_t *zio)
+vdev_raidz_matrix_reconstruct(raidz_map_t *rm, int n, int nmissing,
+ int *missing, uint8_t **invrows, const uint8_t *used)
{
- raidz_col_t *rc = zio->io_private;
+ int i, j, x, cc, c;
+ uint8_t *src;
+ uint64_t ccount;
+ uint8_t *dst[VDEV_RAIDZ_MAXPARITY];
+ uint64_t dcount[VDEV_RAIDZ_MAXPARITY];
+ uint8_t log = 0, 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_PUSHPAGE);
+
+ for (pp = p, i = 0; i < nmissing; i++) {
+ invlog[i] = pp;
+ pp += n;
+ }
- rc->rc_error = zio->io_error;
- rc->rc_tried = 1;
- rc->rc_skipped = 0;
-}
+ 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]];
+ }
+ }
-static int
-vdev_raidz_io_start(zio_t *zio)
+ for (i = 0; i < n; i++) {
+ c = used[i];
+ ASSERT3U(c, <, rm->rm_cols);
+
+ src = rm->rm_col[c].rc_data;
+ ccount = rm->rm_col[c].rc_size;
+ for (j = 0; j < nmissing; j++) {
+ cc = missing[j] + rm->rm_firstdatacol;
+ ASSERT3U(cc, >=, rm->rm_firstdatacol);
+ ASSERT3U(cc, <, rm->rm_cols);
+ ASSERT3U(cc, !=, c);
+
+ dst[j] = rm->rm_col[cc].rc_data;
+ dcount[j] = rm->rm_col[cc].rc_size;
+ }
+
+ ASSERT(ccount >= rm->rm_col[missing[0]].rc_size || i > 0);
+
+ 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 int
+vdev_raidz_reconstruct_general(raidz_map_t *rm, 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;
+
+ int code = 0;
+
+
+ n = rm->rm_cols - rm->rm_firstdatacol;
+
+ /*
+ * Figure out which data columns are missing.
+ */
+ nmissing_rows = 0;
+ for (t = 0; t < ntgts; t++) {
+ if (tgts[t] >= rm->rm_firstdatacol) {
+ missing_rows[nmissing_rows++] =
+ tgts[t] - rm->rm_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 < rm->rm_firstdatacol);
+
+ /*
+ * Skip any targeted parity columns.
+ */
+ if (c == tgts[tt]) {
+ tt++;
+ continue;
+ }
+
+ code |= 1 << c;
+
+ parity_map[i] = c;
+ i++;
+ }
+
+ ASSERT(code != 0);
+ ASSERT3U(code, <, 1 << VDEV_RAIDZ_MAXPARITY);
+
+ psize = (sizeof (rows[0][0]) + sizeof (invrows[0][0])) *
+ nmissing_rows * n + sizeof (used[0]) * n;
+ p = kmem_alloc(psize, KM_PUSHPAGE);
+
+ 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 = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
+ if (tt < nmissing_rows &&
+ c == missing_rows[tt] + rm->rm_firstdatacol) {
+ tt++;
+ continue;
+ }
+
+ ASSERT3S(i, <, n);
+ used[i] = c;
+ i++;
+ }
+
+ /*
+ * Initialize the interesting rows of the matrix.
+ */
+ vdev_raidz_matrix_init(rm, n, nmissing_rows, parity_map, rows);
+
+ /*
+ * Invert the matrix.
+ */
+ vdev_raidz_matrix_invert(rm, n, nmissing_rows, missing_rows, rows,
+ invrows, used);
+
+ /*
+ * Reconstruct the missing data using the generated matrix.
+ */
+ vdev_raidz_matrix_reconstruct(rm, n, nmissing_rows, missing_rows,
+ invrows, used);
+
+ kmem_free(p, psize);
+
+ return (code);
+}
+
+static int
+vdev_raidz_reconstruct(raidz_map_t *rm, int *t, int nt)
+{
+ int tgts[VDEV_RAIDZ_MAXPARITY], *dt;
+ int ntgts;
+ int i, c;
+ int code;
+ int nbadparity, nbaddata;
+ int parity_valid[VDEV_RAIDZ_MAXPARITY];
+
+ /*
+ * The tgts list must already be sorted.
+ */
+ for (i = 1; i < nt; i++) {
+ ASSERT(t[i] > t[i - 1]);
+ }
+
+ nbadparity = rm->rm_firstdatacol;
+ nbaddata = rm->rm_cols - nbadparity;
+ ntgts = 0;
+ for (i = 0, c = 0; c < rm->rm_cols; c++) {
+ if (c < rm->rm_firstdatacol)
+ parity_valid[c] = B_FALSE;
+
+ if (i < nt && c == t[i]) {
+ tgts[ntgts++] = c;
+ i++;
+ } else if (rm->rm_col[c].rc_error != 0) {
+ tgts[ntgts++] = c;
+ } else if (c >= rm->rm_firstdatacol) {
+ nbaddata--;
+ } else {
+ parity_valid[c] = B_TRUE;
+ nbadparity--;
+ }
+ }
+
+ ASSERT(ntgts >= nt);
+ ASSERT(nbaddata >= 0);
+ ASSERT(nbaddata + nbadparity == ntgts);
+
+ dt = &tgts[nbadparity];
+
+ /*
+ * See if we can use any of our optimized reconstruction routines.
+ */
+ if (!vdev_raidz_default_to_general) {
+ switch (nbaddata) {
+ case 1:
+ if (parity_valid[VDEV_RAIDZ_P])
+ return (vdev_raidz_reconstruct_p(rm, dt, 1));
+
+ ASSERT(rm->rm_firstdatacol > 1);
+
+ if (parity_valid[VDEV_RAIDZ_Q])
+ return (vdev_raidz_reconstruct_q(rm, dt, 1));
+
+ ASSERT(rm->rm_firstdatacol > 2);
+ break;
+
+ case 2:
+ ASSERT(rm->rm_firstdatacol > 1);
+
+ if (parity_valid[VDEV_RAIDZ_P] &&
+ parity_valid[VDEV_RAIDZ_Q])
+ return (vdev_raidz_reconstruct_pq(rm, dt, 2));
+
+ ASSERT(rm->rm_firstdatacol > 2);
+
+ break;
+ }
+ }
+
+ code = vdev_raidz_reconstruct_general(rm, tgts, ntgts);
+ ASSERT(code < (1 << VDEV_RAIDZ_MAXPARITY));
+ ASSERT(code > 0);
+ return (code);
+}
+
+static int
+vdev_raidz_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize,
+ uint64_t *ashift)
+{
+ vdev_t *cvd;
+ uint64_t nparity = vd->vdev_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 (EINVAL);
+ }
+
+ vdev_open_children(vd);
+
+ for (c = 0; c < vd->vdev_children; c++) {
+ 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;
+ *ashift = MAX(*ashift, cvd->vdev_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)
+{
+ int c;
+
+ for (c = 0; c < vd->vdev_children; c++)
+ vdev_close(vd->vdev_child[c]);
+}
+
+static uint64_t
+vdev_raidz_asize(vdev_t *vd, uint64_t psize)
+{
+ uint64_t asize;
+ uint64_t ashift = vd->vdev_top->vdev_ashift;
+ uint64_t cols = vd->vdev_children;
+ uint64_t nparity = vd->vdev_nparity;
+
+ asize = ((psize - 1) >> ashift) + 1;
+ asize += nparity * ((asize + cols - nparity - 1) / (cols - nparity));
+ asize = roundup(asize, nparity + 1) << ashift;
+
+ return (asize);
+}
+
+static 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 int
+vdev_raidz_io_start(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
vdev_t *tvd = vd->vdev_top;
vdev_t *cvd;
- blkptr_t *bp = zio->io_bp;
raidz_map_t *rm;
raidz_col_t *rc;
- int c;
+ int c, i;
rm = vdev_raidz_map_alloc(zio, tvd->vdev_ashift, vd->vdev_children,
vd->vdev_nparity);
ASSERT3U(rm->rm_asize, ==, vdev_psize_to_asize(vd, zio->io_size));
if (zio->io_type == ZIO_TYPE_WRITE) {
- /*
- * Generate RAID parity in the first virtual columns.
- */
- if (rm->rm_firstdatacol == 1)
- vdev_raidz_generate_parity_p(rm);
- else
- vdev_raidz_generate_parity_pq(rm);
+ vdev_raidz_generate_parity(rm);
for (c = 0; c < rm->rm_cols; c++) {
rc = &rm->rm_col[c];
vdev_raidz_child_done, rc));
}
+ /*
+ * Generate optional I/Os for any skipped sectors to improve
+ * aggregation contiguity.
+ */
+ for (c = rm->rm_skipstart, i = 0; i < rm->rm_nskip; c++, i++) {
+ ASSERT(c <= rm->rm_scols);
+ if (c == rm->rm_scols)
+ c = 0;
+ rc = &rm->rm_col[c];
+ cvd = vd->vdev_child[rc->rc_devidx];
+ zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
+ rc->rc_offset + rc->rc_size, NULL,
+ 1 << tvd->vdev_ashift,
+ zio->io_type, zio->io_priority,
+ ZIO_FLAG_NODATA | ZIO_FLAG_OPTIONAL, NULL, NULL));
+ }
+
return (ZIO_PIPELINE_CONTINUE);
}
/*
* 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
- * data.
+ * last -- any errors along the way will force us to read the parity.
*/
for (c = rm->rm_cols - 1; c >= 0; c--) {
rc = &rm->rm_col[c];
rc->rc_skipped = 1;
continue;
}
- if (vdev_dtl_contains(&cvd->vdev_dtl_map, bp->blk_birth, 1)) {
+ if (vdev_dtl_contains(cvd, DTL_MISSING, zio->io_txg, 1)) {
if (c >= rm->rm_firstdatacol)
rm->rm_missingdata++;
else
continue;
}
if (c >= rm->rm_firstdatacol || rm->rm_missingdata > 0 ||
- (zio->io_flags & ZIO_FLAG_SCRUB)) {
+ (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) {
zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
rc->rc_offset, rc->rc_data, rc->rc_size,
zio->io_type, zio->io_priority, 0,
return (ZIO_PIPELINE_CONTINUE);
}
+
/*
* Report a checksum error for a child of a RAID-Z device.
*/
static void
-raidz_checksum_error(zio_t *zio, raidz_col_t *rc)
+raidz_checksum_error(zio_t *zio, raidz_col_t *rc, void *bad_data)
{
vdev_t *vd = zio->io_vd->vdev_child[rc->rc_devidx];
if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
+ zio_bad_cksum_t zbc;
+ raidz_map_t *rm = zio->io_vsd;
+
mutex_enter(&vd->vdev_stat_lock);
vd->vdev_stat.vs_checksum_errors++;
mutex_exit(&vd->vdev_stat_lock);
+
+ zbc.zbc_has_cksum = 0;
+ zbc.zbc_injected = rm->rm_ecksuminjected;
+
+ zfs_ereport_post_checksum(zio->io_spa, vd, zio,
+ rc->rc_offset, rc->rc_size, rc->rc_data, bad_data,
+ &zbc);
}
+}
+
+/*
+ * 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;
+ int ret;
- if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE))
- zfs_ereport_post(FM_EREPORT_ZFS_CHECKSUM,
- zio->io_spa, vd, zio, rc->rc_offset, rc->rc_size);
+ bzero(&zbc, sizeof (zio_bad_cksum_t));
+
+ ret = zio_checksum_error(zio, &zbc);
+ if (ret != 0 && zbc.zbc_injected != 0)
+ rm->rm_ecksuminjected = 1;
+
+ return (ret);
}
/*
bcopy(rc->rc_data, orig[c], rc->rc_size);
}
- if (rm->rm_firstdatacol == 1)
- vdev_raidz_generate_parity_p(rm);
- else
- vdev_raidz_generate_parity_pq(rm);
+ vdev_raidz_generate_parity(rm);
for (c = 0; c < rm->rm_firstdatacol; c++) {
rc = &rm->rm_col[c];
if (!rc->rc_tried || rc->rc_error != 0)
continue;
if (bcmp(orig[c], rc->rc_data, rc->rc_size) != 0) {
- raidz_checksum_error(zio, rc);
+ raidz_checksum_error(zio, rc, orig[c]);
rc->rc_error = ECKSUM;
ret++;
}
return (ret);
}
-static uint64_t raidz_corrected_p;
-static uint64_t raidz_corrected_q;
-static uint64_t raidz_corrected_pq;
+/*
+ * Keep statistics on all the ways that we used parity to correct data.
+ */
+static uint64_t raidz_corrected[1 << VDEV_RAIDZ_MAXPARITY];
static int
vdev_raidz_worst_error(raidz_map_t *rm)
{
- int error = 0;
+ int c, error = 0;
- for (int c = 0; c < rm->rm_cols; c++)
+ for (c = 0; c < rm->rm_cols; c++)
error = zio_worst_error(error, rm->rm_col[c].rc_error);
return (error);
}
+/*
+ * Iterate over all combinations of bad data 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.
+ */
+static int
+vdev_raidz_combrec(zio_t *zio, int total_errors, int data_errors)
+{
+ raidz_map_t *rm = zio->io_vsd;
+ raidz_col_t *rc;
+ void *orig[VDEV_RAIDZ_MAXPARITY];
+ int tstore[VDEV_RAIDZ_MAXPARITY + 2];
+ int *tgts = &tstore[1];
+ int curr, next, i, c, n;
+ int code, ret = 0;
+
+ ASSERT(total_errors < rm->rm_firstdatacol);
+
+ /*
+ * This simplifies one edge condition.
+ */
+ tgts[-1] = -1;
+
+ for (n = 1; n <= rm->rm_firstdatacol - total_errors; n++) {
+ /*
+ * Initialize the targets array by finding the first n columns
+ * that contain no error.
+ *
+ * If there were no data errors, we need to ensure that we're
+ * always explicitly attempting to reconstruct at least one
+ * data column. To do this, we simply push the highest target
+ * up into the data columns.
+ */
+ for (c = 0, i = 0; i < n; i++) {
+ if (i == n - 1 && data_errors == 0 &&
+ c < rm->rm_firstdatacol) {
+ c = rm->rm_firstdatacol;
+ }
+
+ while (rm->rm_col[c].rc_error != 0) {
+ c++;
+ ASSERT3S(c, <, rm->rm_cols);
+ }
+
+ tgts[i] = c++;
+ }
+
+ /*
+ * Setting tgts[n] simplifies the other edge condition.
+ */
+ tgts[n] = rm->rm_cols;
+
+ /*
+ * These buffers were allocated in previous iterations.
+ */
+ for (i = 0; i < n - 1; i++) {
+ ASSERT(orig[i] != NULL);
+ }
+
+ orig[n - 1] = zio_buf_alloc(rm->rm_col[0].rc_size);
+
+ curr = 0;
+ next = tgts[curr];
+
+ while (curr != n) {
+ tgts[curr] = next;
+ curr = 0;
+
+ /*
+ * Save off the original data that we're going to
+ * attempt to reconstruct.
+ */
+ for (i = 0; i < n; i++) {
+ ASSERT(orig[i] != NULL);
+ c = tgts[i];
+ ASSERT3S(c, >=, 0);
+ ASSERT3S(c, <, rm->rm_cols);
+ rc = &rm->rm_col[c];
+ bcopy(rc->rc_data, orig[i], rc->rc_size);
+ }
+
+ /*
+ * Attempt a reconstruction and exit the outer loop on
+ * success.
+ */
+ code = vdev_raidz_reconstruct(rm, tgts, n);
+ if (raidz_checksum_verify(zio) == 0) {
+ atomic_inc_64(&raidz_corrected[code]);
+
+ for (i = 0; i < n; i++) {
+ c = tgts[i];
+ rc = &rm->rm_col[c];
+ ASSERT(rc->rc_error == 0);
+ if (rc->rc_tried)
+ raidz_checksum_error(zio, rc,
+ orig[i]);
+ rc->rc_error = ECKSUM;
+ }
+
+ ret = code;
+ goto done;
+ }
+
+ /*
+ * Restore the original data.
+ */
+ for (i = 0; i < n; i++) {
+ c = tgts[i];
+ rc = &rm->rm_col[c];
+ bcopy(orig[i], rc->rc_data, rc->rc_size);
+ }
+
+ do {
+ /*
+ * Find the next valid column after the curr
+ * position..
+ */
+ for (next = tgts[curr] + 1;
+ next < rm->rm_cols &&
+ rm->rm_col[next].rc_error != 0; next++)
+ continue;
+
+ ASSERT(next <= tgts[curr + 1]);
+
+ /*
+ * If that spot is available, we're done here.
+ */
+ if (next != tgts[curr + 1])
+ break;
+
+ /*
+ * Otherwise, find the next valid column after
+ * the previous position.
+ */
+ for (c = tgts[curr - 1] + 1;
+ rm->rm_col[c].rc_error != 0; c++)
+ continue;
+
+ tgts[curr] = c;
+ curr++;
+
+ } while (curr != n);
+ }
+ }
+ n--;
+done:
+ for (i = 0; i < n; i++) {
+ zio_buf_free(orig[i], rm->rm_col[0].rc_size);
+ }
+
+ return (ret);
+}
+
static void
vdev_raidz_io_done(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
vdev_t *cvd;
raidz_map_t *rm = zio->io_vsd;
- raidz_col_t *rc, *rc1;
+ raidz_col_t *rc = NULL;
int unexpected_errors = 0;
int parity_errors = 0;
int parity_untried = 0;
int data_errors = 0;
int total_errors = 0;
- int n, c, c1;
+ int n, c;
+ int tgts[VDEV_RAIDZ_MAXPARITY];
+ int code;
ASSERT(zio->io_bp != NULL); /* XXX need to add code to enforce this */
* any errors.
*/
if (total_errors <= rm->rm_firstdatacol - parity_untried) {
- switch (data_errors) {
- case 0:
- if (zio_checksum_error(zio) == 0) {
+ if (data_errors == 0) {
+ if (raidz_checksum_verify(zio) == 0) {
/*
* If we read parity information (unnecessarily
* as it happens since no reconstruction was
}
goto done;
}
- break;
-
- case 1:
+ } else {
/*
* We either attempt to read all the parity columns or
* none of them. If we didn't try to read parity, we
ASSERT(parity_errors < rm->rm_firstdatacol);
/*
- * Find the column that reported the error.
+ * Identify the data columns that reported an error.
*/
+ n = 0;
for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
rc = &rm->rm_col[c];
- if (rc->rc_error != 0)
- break;
+ if (rc->rc_error != 0) {
+ ASSERT(n < VDEV_RAIDZ_MAXPARITY);
+ tgts[n++] = c;
+ }
}
- ASSERT(c != rm->rm_cols);
- ASSERT(!rc->rc_skipped || rc->rc_error == ENXIO ||
- rc->rc_error == ESTALE);
- if (rm->rm_col[VDEV_RAIDZ_P].rc_error == 0) {
- vdev_raidz_reconstruct_p(rm, c);
- } else {
- ASSERT(rm->rm_firstdatacol > 1);
- vdev_raidz_reconstruct_q(rm, c);
- }
+ ASSERT(rm->rm_firstdatacol >= n);
- if (zio_checksum_error(zio) == 0) {
- if (rm->rm_col[VDEV_RAIDZ_P].rc_error == 0)
- atomic_inc_64(&raidz_corrected_p);
- else
- atomic_inc_64(&raidz_corrected_q);
+ code = vdev_raidz_reconstruct(rm, tgts, n);
+
+ if (raidz_checksum_verify(zio) == 0) {
+ atomic_inc_64(&raidz_corrected[code]);
/*
- * If there's more than one parity disk that
- * was successfully read, confirm that the
- * other parity disk produced the correct data.
- * This routine is suboptimal in that it
- * regenerates both the parity we wish to test
- * as well as the parity we just used to
- * perform the reconstruction, but this should
- * be a relatively uncommon case, and can be
- * optimized if it becomes a problem.
- * We also regenerate parity when resilvering
- * so we can write it out to the failed device
- * later.
+ * If we read more parity disks than were used
+ * for reconstruction, confirm that the other
+ * parity disks produced correct data. This
+ * routine is suboptimal in that it regenerates
+ * the parity that we already used in addition
+ * to the parity that we're attempting to
+ * verify, but this should be a relatively
+ * uncommon case, and can be optimized if it
+ * becomes a problem. Note that we regenerate
+ * parity when resilvering so we can write it
+ * out to failed devices later.
*/
- if (parity_errors < rm->rm_firstdatacol - 1 ||
+ if (parity_errors < rm->rm_firstdatacol - n ||
(zio->io_flags & ZIO_FLAG_RESILVER)) {
n = raidz_parity_verify(zio, rm);
unexpected_errors += n;
goto done;
}
- break;
-
- case 2:
- /*
- * Two data column errors require double parity.
- */
- ASSERT(rm->rm_firstdatacol == 2);
-
- /*
- * Find the two columns that reported errors.
- */
- for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
- rc = &rm->rm_col[c];
- if (rc->rc_error != 0)
- break;
- }
- ASSERT(c != rm->rm_cols);
- ASSERT(!rc->rc_skipped || rc->rc_error == ENXIO ||
- rc->rc_error == ESTALE);
-
- for (c1 = c++; c < rm->rm_cols; c++) {
- rc = &rm->rm_col[c];
- if (rc->rc_error != 0)
- break;
- }
- ASSERT(c != rm->rm_cols);
- ASSERT(!rc->rc_skipped || rc->rc_error == ENXIO ||
- rc->rc_error == ESTALE);
-
- vdev_raidz_reconstruct_pq(rm, c1, c);
-
- if (zio_checksum_error(zio) == 0) {
- atomic_inc_64(&raidz_corrected_pq);
- goto done;
- }
- break;
-
- default:
- ASSERT(rm->rm_firstdatacol <= 2);
- ASSERT(0);
}
}
* errors we detected, and we've attempted to read all columns. There
* must, therefore, be one or more additional problems -- silent errors
* resulting in invalid data rather than explicit I/O errors resulting
- * in absent data. Before we attempt combinatorial reconstruction make
- * sure we have a chance of coming up with the right answer.
+ * in absent data. We check if there is enough additional data to
+ * possibly reconstruct the data and then perform combinatorial
+ * reconstruction over all possible combinations. If that fails,
+ * we're cooked.
*/
- if (total_errors >= rm->rm_firstdatacol) {
+ if (total_errors > rm->rm_firstdatacol) {
zio->io_error = vdev_raidz_worst_error(rm);
- /*
- * If there were exactly as many device errors as parity
- * columns, yet we couldn't reconstruct the data, then at
- * least one device must have returned bad data silently.
- */
- if (total_errors == rm->rm_firstdatacol)
- zio->io_error = zio_worst_error(zio->io_error, ECKSUM);
- goto done;
- }
-
- if (rm->rm_col[VDEV_RAIDZ_P].rc_error == 0) {
- /*
- * Attempt to reconstruct the data from parity P.
- */
- for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
- void *orig;
- rc = &rm->rm_col[c];
-
- orig = zio_buf_alloc(rc->rc_size);
- bcopy(rc->rc_data, orig, rc->rc_size);
- vdev_raidz_reconstruct_p(rm, c);
-
- if (zio_checksum_error(zio) == 0) {
- zio_buf_free(orig, rc->rc_size);
- atomic_inc_64(&raidz_corrected_p);
- /*
- * If this child didn't know that it returned
- * bad data, inform it.
- */
- if (rc->rc_tried && rc->rc_error == 0)
- raidz_checksum_error(zio, rc);
- rc->rc_error = ECKSUM;
- goto done;
- }
-
- bcopy(orig, rc->rc_data, rc->rc_size);
- zio_buf_free(orig, rc->rc_size);
- }
- }
-
- if (rm->rm_firstdatacol > 1 && rm->rm_col[VDEV_RAIDZ_Q].rc_error == 0) {
+ } else if (total_errors < rm->rm_firstdatacol &&
+ (code = vdev_raidz_combrec(zio, total_errors, data_errors)) != 0) {
/*
- * Attempt to reconstruct the data from parity Q.
+ * If we didn't use all the available parity for the
+ * combinatorial reconstruction, verify that the remaining
+ * parity is correct.
*/
- for (c = rm->rm_firstdatacol; c < rm->rm_cols; c++) {
- void *orig;
- rc = &rm->rm_col[c];
-
- orig = zio_buf_alloc(rc->rc_size);
- bcopy(rc->rc_data, orig, rc->rc_size);
- vdev_raidz_reconstruct_q(rm, c);
-
- if (zio_checksum_error(zio) == 0) {
- zio_buf_free(orig, rc->rc_size);
- atomic_inc_64(&raidz_corrected_q);
-
- /*
- * If this child didn't know that it returned
- * bad data, inform it.
- */
- if (rc->rc_tried && rc->rc_error == 0)
- raidz_checksum_error(zio, rc);
- rc->rc_error = ECKSUM;
- goto done;
- }
-
- bcopy(orig, rc->rc_data, rc->rc_size);
- zio_buf_free(orig, rc->rc_size);
- }
- }
-
- if (rm->rm_firstdatacol > 1 &&
- rm->rm_col[VDEV_RAIDZ_P].rc_error == 0 &&
- rm->rm_col[VDEV_RAIDZ_Q].rc_error == 0) {
+ if (code != (1 << rm->rm_firstdatacol) - 1)
+ (void) raidz_parity_verify(zio, rm);
+ } else {
/*
- * Attempt to reconstruct the data from both P and Q.
+ * We're here because either:
+ *
+ * total_errors == rm_first_datacol, or
+ * vdev_raidz_combrec() failed
+ *
+ * In either case, there is enough bad data to prevent
+ * reconstruction.
+ *
+ * Start checksum ereports for all children which haven't
+ * failed, and the IO wasn't speculative.
*/
- for (c = rm->rm_firstdatacol; c < rm->rm_cols - 1; c++) {
- void *orig, *orig1;
- rc = &rm->rm_col[c];
-
- orig = zio_buf_alloc(rc->rc_size);
- bcopy(rc->rc_data, orig, rc->rc_size);
-
- for (c1 = c + 1; c1 < rm->rm_cols; c1++) {
- rc1 = &rm->rm_col[c1];
-
- orig1 = zio_buf_alloc(rc1->rc_size);
- bcopy(rc1->rc_data, orig1, rc1->rc_size);
-
- vdev_raidz_reconstruct_pq(rm, c, c1);
+ zio->io_error = ECKSUM;
- if (zio_checksum_error(zio) == 0) {
- zio_buf_free(orig, rc->rc_size);
- zio_buf_free(orig1, rc1->rc_size);
- atomic_inc_64(&raidz_corrected_pq);
-
- /*
- * If these children didn't know they
- * returned bad data, inform them.
- */
- if (rc->rc_tried && rc->rc_error == 0)
- raidz_checksum_error(zio, rc);
- if (rc1->rc_tried && rc1->rc_error == 0)
- raidz_checksum_error(zio, rc1);
-
- rc->rc_error = ECKSUM;
- rc1->rc_error = ECKSUM;
-
- goto done;
+ if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
+ for (c = 0; c < rm->rm_cols; c++) {
+ rc = &rm->rm_col[c];
+ if (rc->rc_error == 0) {
+ zio_bad_cksum_t zbc;
+ zbc.zbc_has_cksum = 0;
+ zbc.zbc_injected =
+ rm->rm_ecksuminjected;
+
+ zfs_ereport_start_checksum(
+ zio->io_spa,
+ vd->vdev_child[rc->rc_devidx],
+ zio, rc->rc_offset, rc->rc_size,
+ (void *)(uintptr_t)c, &zbc);
}
-
- bcopy(orig1, rc1->rc_data, rc1->rc_size);
- zio_buf_free(orig1, rc1->rc_size);
}
-
- bcopy(orig, rc->rc_data, rc->rc_size);
- zio_buf_free(orig, rc->rc_size);
- }
- }
-
- /*
- * All combinations failed to checksum. Generate checksum ereports for
- * all children.
- */
- zio->io_error = ECKSUM;
-
- if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
- for (c = 0; c < rm->rm_cols; c++) {
- rc = &rm->rm_col[c];
- zfs_ereport_post(FM_EREPORT_ZFS_CHECKSUM,
- zio->io_spa, vd->vdev_child[rc->rc_devidx], zio,
- rc->rc_offset, rc->rc_size);
}
}
done:
zio_checksum_verified(zio);
- if (zio->io_error == 0 && (spa_mode & FWRITE) &&
+ if (zio->io_error == 0 && spa_writeable(zio->io_spa) &&
(unexpected_errors || (zio->io_flags & ZIO_FLAG_RESILVER))) {
/*
* Use the good data we have in hand to repair damaged children.
zio_nowait(zio_vdev_child_io(zio, NULL, cvd,
rc->rc_offset, rc->rc_data, rc->rc_size,
ZIO_TYPE_WRITE, zio->io_priority,
- ZIO_FLAG_IO_REPAIR, NULL, NULL));
+ ZIO_FLAG_IO_REPAIR | (unexpected_errors ?
+ ZIO_FLAG_SELF_HEAL : 0), NULL, NULL));
}
}
}
vdev_raidz_io_start,
vdev_raidz_io_done,
vdev_raidz_state_change,
+ NULL,
+ NULL,
VDEV_TYPE_RAIDZ, /* name of this vdev type */
B_FALSE /* not a leaf vdev */
};
git://git.camperquake.de / zfs.git / blobdiff