--- a/usr/src/uts/common/fs/zfs/zio.c Mon Sep 29 17:35:19 2008 -0700
+++ b/usr/src/uts/common/fs/zfs/zio.c Mon Sep 29 18:13:58 2008 -0700
@@ -23,8 +23,6 @@
* Use is subject to license terms.
*/
-#pragma ident "%Z%%M% %I% %E% SMI"
-
#include <sys/zfs_context.h>
#include <sys/fm/fs/zfs.h>
#include <sys/spa.h>
@@ -61,30 +59,9 @@
char *zio_type_name[ZIO_TYPES] = {
"null", "read", "write", "free", "claim", "ioctl" };
-/* Force an allocation failure when non-zero */
-uint16_t zio_zil_fail_shift = 0;
-uint16_t zio_io_fail_shift = 0;
-
-/* Enable/disable the write-retry logic */
-int zio_write_retry = 1;
-
-/* Taskq to handle reissuing of I/Os */
-taskq_t *zio_taskq;
-int zio_resume_threads = 4;
-
-typedef struct zio_sync_pass {
- int zp_defer_free; /* defer frees after this pass */
- int zp_dontcompress; /* don't compress after this pass */
- int zp_rewrite; /* rewrite new bps after this pass */
-} zio_sync_pass_t;
-
-zio_sync_pass_t zio_sync_pass = {
- 1, /* zp_defer_free */
- 4, /* zp_dontcompress */
- 1, /* zp_rewrite */
-};
-
-static boolean_t zio_io_should_fail(uint16_t);
+#define SYNC_PASS_DEFERRED_FREE 1 /* defer frees after this pass */
+#define SYNC_PASS_DONT_COMPRESS 4 /* don't compress after this pass */
+#define SYNC_PASS_REWRITE 1 /* rewrite new bps after this pass */
/*
* ==========================================================================
@@ -100,22 +77,8 @@
#endif
/*
- * Determine if we are allowed to issue the IO based on the
- * pool state. If we must wait then block until we are told
- * that we may continue.
- */
-#define ZIO_ENTER(spa) { \
- if (spa->spa_state == POOL_STATE_IO_FAILURE) { \
- mutex_enter(&spa->spa_zio_lock); \
- while (spa->spa_state == POOL_STATE_IO_FAILURE) \
- cv_wait(&spa->spa_zio_cv, &spa->spa_zio_lock); \
- mutex_exit(&spa->spa_zio_lock); \
- } \
-}
-
-/*
- * An allocation zio is one that either currently has the DVA allocate
- * stage set or will have it later in it's lifetime.
+ * An allocating zio is one that either currently has the DVA allocate
+ * stage set or will have it later in its lifetime.
*/
#define IO_IS_ALLOCATING(zio) \
((zio)->io_orig_pipeline & (1U << ZIO_STAGE_DVA_ALLOCATE))
@@ -129,7 +92,6 @@
#ifdef _KERNEL
data_alloc_arena = zio_alloc_arena;
#endif
-
zio_cache = kmem_cache_create("zio_cache", sizeof (zio_t), 0,
NULL, NULL, NULL, NULL, NULL, 0);
@@ -165,7 +127,6 @@
zio_data_buf_cache[c] = kmem_cache_create(name, size,
align, NULL, NULL, NULL, NULL, data_alloc_arena,
KMC_NODEBUG);
-
}
}
@@ -179,9 +140,6 @@
zio_data_buf_cache[c - 1] = zio_data_buf_cache[c];
}
- zio_taskq = taskq_create("zio_taskq", zio_resume_threads,
- maxclsyspri, 50, INT_MAX, TASKQ_PREPOPULATE);
-
zio_inject_init();
}
@@ -206,8 +164,6 @@
zio_data_buf_cache[c] = NULL;
}
- taskq_destroy(zio_taskq);
-
kmem_cache_destroy(zio_cache);
zio_inject_fini();
@@ -277,13 +233,15 @@
* ==========================================================================
*/
static void
-zio_push_transform(zio_t *zio, void *data, uint64_t size, uint64_t bufsize)
+zio_push_transform(zio_t *zio, void *data, uint64_t size, uint64_t bufsize,
+ zio_transform_func_t *transform)
{
zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP);
- zt->zt_data = data;
- zt->zt_size = size;
+ zt->zt_orig_data = zio->io_data;
+ zt->zt_orig_size = zio->io_size;
zt->zt_bufsize = bufsize;
+ zt->zt_transform = transform;
zt->zt_next = zio->io_transform_stack;
zio->io_transform_stack = zt;
@@ -293,158 +251,231 @@
}
static void
-zio_pop_transform(zio_t *zio, void **data, uint64_t *size, uint64_t *bufsize)
+zio_pop_transforms(zio_t *zio)
{
- zio_transform_t *zt = zio->io_transform_stack;
-
- *data = zt->zt_data;
- *size = zt->zt_size;
- *bufsize = zt->zt_bufsize;
-
- zio->io_transform_stack = zt->zt_next;
- kmem_free(zt, sizeof (zio_transform_t));
+ zio_transform_t *zt;
- if ((zt = zio->io_transform_stack) != NULL) {
- zio->io_data = zt->zt_data;
- zio->io_size = zt->zt_size;
- }
-}
+ while ((zt = zio->io_transform_stack) != NULL) {
+ if (zt->zt_transform != NULL)
+ zt->zt_transform(zio,
+ zt->zt_orig_data, zt->zt_orig_size);
-static void
-zio_clear_transform_stack(zio_t *zio)
-{
- void *data;
- uint64_t size, bufsize;
+ zio_buf_free(zio->io_data, zt->zt_bufsize);
- ASSERT(zio->io_transform_stack != NULL);
+ zio->io_data = zt->zt_orig_data;
+ zio->io_size = zt->zt_orig_size;
+ zio->io_transform_stack = zt->zt_next;
- zio_pop_transform(zio, &data, &size, &bufsize);
- while (zio->io_transform_stack != NULL) {
- zio_buf_free(data, bufsize);
- zio_pop_transform(zio, &data, &size, &bufsize);
+ kmem_free(zt, sizeof (zio_transform_t));
}
}
/*
* ==========================================================================
- * Create the various types of I/O (read, write, free)
+ * I/O transform callbacks for subblocks and decompression
+ * ==========================================================================
+ */
+static void
+zio_subblock(zio_t *zio, void *data, uint64_t size)
+{
+ ASSERT(zio->io_size > size);
+
+ if (zio->io_type == ZIO_TYPE_READ)
+ bcopy(zio->io_data, data, size);
+}
+
+static void
+zio_decompress(zio_t *zio, void *data, uint64_t size)
+{
+ if (zio->io_error == 0 &&
+ zio_decompress_data(BP_GET_COMPRESS(zio->io_bp),
+ zio->io_data, zio->io_size, data, size) != 0)
+ zio->io_error = EIO;
+}
+
+/*
+ * ==========================================================================
+ * I/O parent/child relationships and pipeline interlocks
+ * ==========================================================================
+ */
+
+static void
+zio_add_child(zio_t *pio, zio_t *zio)
+{
+ mutex_enter(&pio->io_lock);
+ if (zio->io_stage < ZIO_STAGE_READY)
+ pio->io_children[zio->io_child_type][ZIO_WAIT_READY]++;
+ if (zio->io_stage < ZIO_STAGE_DONE)
+ pio->io_children[zio->io_child_type][ZIO_WAIT_DONE]++;
+ zio->io_sibling_prev = NULL;
+ zio->io_sibling_next = pio->io_child;
+ if (pio->io_child != NULL)
+ pio->io_child->io_sibling_prev = zio;
+ pio->io_child = zio;
+ zio->io_parent = pio;
+ mutex_exit(&pio->io_lock);
+}
+
+static void
+zio_remove_child(zio_t *pio, zio_t *zio)
+{
+ zio_t *next, *prev;
+
+ ASSERT(zio->io_parent == pio);
+
+ mutex_enter(&pio->io_lock);
+ next = zio->io_sibling_next;
+ prev = zio->io_sibling_prev;
+ if (next != NULL)
+ next->io_sibling_prev = prev;
+ if (prev != NULL)
+ prev->io_sibling_next = next;
+ if (pio->io_child == zio)
+ pio->io_child = next;
+ mutex_exit(&pio->io_lock);
+}
+
+static boolean_t
+zio_wait_for_children(zio_t *zio, enum zio_child child, enum zio_wait_type wait)
+{
+ uint64_t *countp = &zio->io_children[child][wait];
+ boolean_t waiting = B_FALSE;
+
+ mutex_enter(&zio->io_lock);
+ ASSERT(zio->io_stall == NULL);
+ if (*countp != 0) {
+ zio->io_stage--;
+ zio->io_stall = countp;
+ waiting = B_TRUE;
+ }
+ mutex_exit(&zio->io_lock);
+
+ return (waiting);
+}
+
+static void
+zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait)
+{
+ uint64_t *countp = &pio->io_children[zio->io_child_type][wait];
+ int *errorp = &pio->io_child_error[zio->io_child_type];
+
+ mutex_enter(&pio->io_lock);
+ if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE))
+ *errorp = zio_worst_error(*errorp, zio->io_error);
+ pio->io_reexecute |= zio->io_reexecute;
+ ASSERT3U(*countp, >, 0);
+ if (--*countp == 0 && pio->io_stall == countp) {
+ pio->io_stall = NULL;
+ mutex_exit(&pio->io_lock);
+ zio_execute(pio);
+ } else {
+ mutex_exit(&pio->io_lock);
+ }
+}
+
+static void
+zio_inherit_child_errors(zio_t *zio, enum zio_child c)
+{
+ if (zio->io_child_error[c] != 0 && zio->io_error == 0)
+ zio->io_error = zio->io_child_error[c];
+}
+
+/*
+ * ==========================================================================
+ * Create the various types of I/O (read, write, free, etc)
* ==========================================================================
*/
static zio_t *
zio_create(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
void *data, uint64_t size, zio_done_func_t *done, void *private,
- zio_type_t type, int priority, int flags, uint8_t stage, uint32_t pipeline)
+ zio_type_t type, int priority, int flags, vdev_t *vd, uint64_t offset,
+ const zbookmark_t *zb, uint8_t stage, uint32_t pipeline)
{
zio_t *zio;
ASSERT3U(size, <=, SPA_MAXBLOCKSIZE);
ASSERT(P2PHASE(size, SPA_MINBLOCKSIZE) == 0);
+ ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0);
- /* Only we should set CONFIG_GRABBED */
- ASSERT(!(flags & ZIO_FLAG_CONFIG_GRABBED));
+ ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));
+ ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER));
+ ASSERT(vd || stage == ZIO_STAGE_OPEN);
zio = kmem_cache_alloc(zio_cache, KM_SLEEP);
bzero(zio, sizeof (zio_t));
- zio->io_parent = pio;
- zio->io_spa = spa;
- zio->io_txg = txg;
- zio->io_flags = flags;
+
+ mutex_init(&zio->io_lock, NULL, MUTEX_DEFAULT, NULL);
+ cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL);
+
+ if (vd != NULL)
+ zio->io_child_type = ZIO_CHILD_VDEV;
+ else if (flags & ZIO_FLAG_GANG_CHILD)
+ zio->io_child_type = ZIO_CHILD_GANG;
+ else
+ zio->io_child_type = ZIO_CHILD_LOGICAL;
+
if (bp != NULL) {
zio->io_bp = bp;
zio->io_bp_copy = *bp;
zio->io_bp_orig = *bp;
+ if (type != ZIO_TYPE_WRITE)
+ zio->io_bp = &zio->io_bp_copy; /* so caller can free */
+ if (zio->io_child_type == ZIO_CHILD_LOGICAL) {
+ if (BP_IS_GANG(bp))
+ pipeline |= ZIO_GANG_STAGES;
+ zio->io_logical = zio;
+ }
}
+
+ zio->io_spa = spa;
+ zio->io_txg = txg;
+ zio->io_data = data;
+ zio->io_size = size;
zio->io_done = done;
zio->io_private = private;
zio->io_type = type;
zio->io_priority = priority;
- zio->io_stage = stage;
- zio->io_pipeline = pipeline;
- zio->io_timestamp = lbolt64;
- mutex_init(&zio->io_lock, NULL, MUTEX_DEFAULT, NULL);
- cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL);
- zio_push_transform(zio, data, size, size);
+ zio->io_vd = vd;
+ zio->io_offset = offset;
+ zio->io_orig_flags = zio->io_flags = flags;
+ zio->io_orig_stage = zio->io_stage = stage;
+ zio->io_orig_pipeline = zio->io_pipeline = pipeline;
+
+ if (zb != NULL)
+ zio->io_bookmark = *zb;
- /*
- * Note on config lock:
- *
- * If CONFIG_HELD is set, then the caller already has the config
- * lock, so we don't need it for this io.
- *
- * We set CONFIG_GRABBED to indicate that we have grabbed the
- * config lock on behalf of this io, so it should be released
- * in zio_done.
- *
- * Unless CONFIG_HELD is set, we will grab the config lock for
- * any top-level (parent-less) io, *except* NULL top-level ios.
- * The NULL top-level ios rarely have any children, so we delay
- * grabbing the lock until the first child is added (but it is
- * still grabbed on behalf of the top-level i/o, so additional
- * children don't need to also grab it). This greatly reduces
- * contention on the config lock.
- */
- if (pio == NULL) {
- if (type != ZIO_TYPE_NULL &&
- !(flags & ZIO_FLAG_CONFIG_HELD)) {
- spa_config_enter(spa, RW_READER, zio);
- zio->io_flags |= ZIO_FLAG_CONFIG_GRABBED;
- }
- zio->io_root = zio;
- } else {
- zio->io_root = pio->io_root;
- if (!(flags & ZIO_FLAG_NOBOOKMARK))
+ if (pio != NULL) {
+ /*
+ * Logical I/Os can have logical, gang, or vdev children.
+ * Gang I/Os can have gang or vdev children.
+ * Vdev I/Os can only have vdev children.
+ * The following ASSERT captures all of these constraints.
+ */
+ ASSERT(zio->io_child_type <= pio->io_child_type);
+ if (zio->io_logical == NULL)
zio->io_logical = pio->io_logical;
- mutex_enter(&pio->io_lock);
- if (pio->io_parent == NULL &&
- pio->io_type == ZIO_TYPE_NULL &&
- !(pio->io_flags & ZIO_FLAG_CONFIG_GRABBED) &&
- !(pio->io_flags & ZIO_FLAG_CONFIG_HELD)) {
- pio->io_flags |= ZIO_FLAG_CONFIG_GRABBED;
- spa_config_enter(spa, RW_READER, pio);
- }
- if (stage < ZIO_STAGE_READY)
- pio->io_children_notready++;
- pio->io_children_notdone++;
- zio->io_sibling_next = pio->io_child;
- zio->io_sibling_prev = NULL;
- if (pio->io_child != NULL)
- pio->io_child->io_sibling_prev = zio;
- pio->io_child = zio;
- zio->io_ndvas = pio->io_ndvas;
- mutex_exit(&pio->io_lock);
+ zio_add_child(pio, zio);
}
- /*
- * Save off the original state incase we need to retry later.
- */
- zio->io_orig_stage = zio->io_stage;
- zio->io_orig_pipeline = zio->io_pipeline;
- zio->io_orig_flags = zio->io_flags;
-
- /*
- * If this is not a null zio, and config is not already held,
- * then the root zio should have grabbed the config lock.
- * If this is not a root zio, it should not have grabbed the
- * config lock.
- */
- ASSERT((zio->io_root->io_flags & ZIO_FLAG_CONFIG_HELD) ||
- zio->io_type == ZIO_TYPE_NULL ||
- (zio->io_root->io_flags & ZIO_FLAG_CONFIG_GRABBED));
- ASSERT(zio->io_root == zio ||
- !(zio->io_flags & ZIO_FLAG_CONFIG_GRABBED));
-
return (zio);
}
static void
-zio_reset(zio_t *zio)
+zio_destroy(zio_t *zio)
{
- zio_clear_transform_stack(zio);
+ spa_t *spa = zio->io_spa;
+ uint8_t async_root = zio->io_async_root;
- zio->io_flags = zio->io_orig_flags;
- zio->io_stage = zio->io_orig_stage;
- zio->io_pipeline = zio->io_orig_pipeline;
- zio_push_transform(zio, zio->io_data, zio->io_size, zio->io_size);
+ mutex_destroy(&zio->io_lock);
+ cv_destroy(&zio->io_cv);
+ kmem_cache_free(zio_cache, zio);
+
+ if (async_root) {
+ mutex_enter(&spa->spa_async_root_lock);
+ if (--spa->spa_async_root_count == 0)
+ cv_broadcast(&spa->spa_async_root_cv);
+ mutex_exit(&spa->spa_async_root_lock);
+ }
}
zio_t *
@@ -454,8 +485,8 @@
zio_t *zio;
zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
- ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, ZIO_STAGE_OPEN,
- ZIO_WAIT_FOR_CHILDREN_PIPELINE);
+ ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, NULL, 0, NULL,
+ ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE);
return (zio);
}
@@ -467,161 +498,89 @@
}
zio_t *
-zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
- uint64_t size, zio_done_func_t *done, void *private,
+zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
+ void *data, uint64_t size, zio_done_func_t *done, void *private,
int priority, int flags, const zbookmark_t *zb)
{
zio_t *zio;
- ASSERT3U(size, ==, BP_GET_LSIZE(bp));
-
- /*
- * If the user has specified that we allow I/Os to continue
- * then attempt to satisfy the read.
- */
- if (spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE)
- ZIO_ENTER(spa);
-
zio = zio_create(pio, spa, bp->blk_birth, (blkptr_t *)bp,
data, size, done, private,
- ZIO_TYPE_READ, priority, flags | ZIO_FLAG_USER,
+ ZIO_TYPE_READ, priority, flags, NULL, 0, zb,
ZIO_STAGE_OPEN, ZIO_READ_PIPELINE);
- zio->io_bookmark = *zb;
-
- zio->io_logical = zio;
-
- /*
- * Work off our copy of the bp so the caller can free it.
- */
- zio->io_bp = &zio->io_bp_copy;
return (zio);
}
zio_t *
-zio_write(zio_t *pio, spa_t *spa, int checksum, int compress, int ncopies,
- uint64_t txg, blkptr_t *bp, void *data, uint64_t size,
- zio_done_func_t *ready, zio_done_func_t *done, void *private, int priority,
- int flags, const zbookmark_t *zb)
+zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
+ void *data, uint64_t size, zio_prop_t *zp,
+ zio_done_func_t *ready, zio_done_func_t *done, void *private,
+ int priority, int flags, const zbookmark_t *zb)
{
zio_t *zio;
- ASSERT(checksum >= ZIO_CHECKSUM_OFF &&
- checksum < ZIO_CHECKSUM_FUNCTIONS);
-
- ASSERT(compress >= ZIO_COMPRESS_OFF &&
- compress < ZIO_COMPRESS_FUNCTIONS);
-
- ZIO_ENTER(spa);
+ ASSERT(zp->zp_checksum >= ZIO_CHECKSUM_OFF &&
+ zp->zp_checksum < ZIO_CHECKSUM_FUNCTIONS &&
+ zp->zp_compress >= ZIO_COMPRESS_OFF &&
+ zp->zp_compress < ZIO_COMPRESS_FUNCTIONS &&
+ zp->zp_type < DMU_OT_NUMTYPES &&
+ zp->zp_level < 32 &&
+ zp->zp_ndvas > 0 &&
+ zp->zp_ndvas <= spa_max_replication(spa));
+ ASSERT(ready != NULL);
zio = zio_create(pio, spa, txg, bp, data, size, done, private,
- ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_USER,
+ ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
ZIO_STAGE_OPEN, ZIO_WRITE_PIPELINE);
zio->io_ready = ready;
-
- zio->io_bookmark = *zb;
-
- zio->io_logical = zio;
-
- zio->io_checksum = checksum;
- zio->io_compress = compress;
- zio->io_ndvas = ncopies;
-
- if (bp->blk_birth != txg) {
- /* XXX the bp usually (always?) gets re-zeroed later */
- BP_ZERO(bp);
- BP_SET_LSIZE(bp, size);
- BP_SET_PSIZE(bp, size);
- } else {
- /* Make sure someone doesn't change their mind on overwrites */
- ASSERT(MIN(zio->io_ndvas + BP_IS_GANG(bp),
- spa_max_replication(spa)) == BP_GET_NDVAS(bp));
- }
+ zio->io_prop = *zp;
return (zio);
}
zio_t *
-zio_rewrite(zio_t *pio, spa_t *spa, int checksum, uint64_t txg,
- blkptr_t *bp, void *data, uint64_t size, zio_done_func_t *done,
- void *private, int priority, int flags, zbookmark_t *zb)
+zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data,
+ uint64_t size, zio_done_func_t *done, void *private, int priority,
+ int flags, zbookmark_t *zb)
{
zio_t *zio;
zio = zio_create(pio, spa, txg, bp, data, size, done, private,
- ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_USER,
- ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE(bp));
-
- zio->io_bookmark = *zb;
- zio->io_checksum = checksum;
- zio->io_compress = ZIO_COMPRESS_OFF;
-
- if (pio != NULL)
- ASSERT3U(zio->io_ndvas, <=, BP_GET_NDVAS(bp));
-
- return (zio);
-}
-
-static void
-zio_write_allocate_ready(zio_t *zio)
-{
- /* Free up the previous block */
- if (!BP_IS_HOLE(&zio->io_bp_orig)) {
- zio_nowait(zio_free(zio, zio->io_spa, zio->io_txg,
- &zio->io_bp_orig, NULL, NULL));
- }
-}
-
-static zio_t *
-zio_write_allocate(zio_t *pio, spa_t *spa, int checksum,
- uint64_t txg, blkptr_t *bp, void *data, uint64_t size,
- zio_done_func_t *done, void *private, int priority, int flags)
-{
- zio_t *zio;
-
- BP_ZERO(bp);
- BP_SET_LSIZE(bp, size);
- BP_SET_PSIZE(bp, size);
- BP_SET_COMPRESS(bp, ZIO_COMPRESS_OFF);
-
- zio = zio_create(pio, spa, txg, bp, data, size, done, private,
- ZIO_TYPE_WRITE, priority, flags,
- ZIO_STAGE_OPEN, ZIO_WRITE_ALLOCATE_PIPELINE);
-
- zio->io_checksum = checksum;
- zio->io_compress = ZIO_COMPRESS_OFF;
- zio->io_ready = zio_write_allocate_ready;
+ ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
+ ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE);
return (zio);
}
zio_t *
zio_free(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
- zio_done_func_t *done, void *private)
+ zio_done_func_t *done, void *private, int flags)
{
zio_t *zio;
ASSERT(!BP_IS_HOLE(bp));
+ if (bp->blk_fill == BLK_FILL_ALREADY_FREED)
+ return (zio_null(pio, spa, NULL, NULL, flags));
+
if (txg == spa->spa_syncing_txg &&
- spa->spa_sync_pass > zio_sync_pass.zp_defer_free) {
+ spa_sync_pass(spa) > SYNC_PASS_DEFERRED_FREE) {
bplist_enqueue_deferred(&spa->spa_sync_bplist, bp);
- return (zio_null(pio, spa, NULL, NULL, 0));
+ return (zio_null(pio, spa, NULL, NULL, flags));
}
- zio = zio_create(pio, spa, txg, bp, NULL, 0, done, private,
- ZIO_TYPE_FREE, ZIO_PRIORITY_FREE, ZIO_FLAG_USER,
- ZIO_STAGE_OPEN, ZIO_FREE_PIPELINE(bp));
-
- zio->io_bp = &zio->io_bp_copy;
+ zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
+ done, private, ZIO_TYPE_FREE, ZIO_PRIORITY_FREE, flags,
+ NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_FREE_PIPELINE);
return (zio);
}
zio_t *
zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
- zio_done_func_t *done, void *private)
+ zio_done_func_t *done, void *private, int flags)
{
zio_t *zio;
@@ -639,11 +598,9 @@
ASSERT3U(spa->spa_uberblock.ub_rootbp.blk_birth, <, spa_first_txg(spa));
ASSERT3U(spa_first_txg(spa), <=, txg);
- zio = zio_create(pio, spa, txg, bp, NULL, 0, done, private,
- ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, 0,
- ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE(bp));
-
- zio->io_bp = &zio->io_bp_copy;
+ zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
+ done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, flags,
+ NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE);
return (zio);
}
@@ -657,10 +614,9 @@
if (vd->vdev_children == 0) {
zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
- ZIO_TYPE_IOCTL, priority, flags,
+ ZIO_TYPE_IOCTL, priority, flags, vd, 0, NULL,
ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE);
- zio->io_vd = vd;
zio->io_cmd = cmd;
} else {
zio = zio_null(pio, spa, NULL, NULL, flags);
@@ -673,60 +629,23 @@
return (zio);
}
-static void
-zio_phys_bp_init(vdev_t *vd, blkptr_t *bp, uint64_t offset, uint64_t size,
- int checksum, boolean_t labels)
-{
- ASSERT(vd->vdev_children == 0);
-
- ASSERT(size <= SPA_MAXBLOCKSIZE);
- ASSERT(P2PHASE(size, SPA_MINBLOCKSIZE) == 0);
- ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0);
-
-#ifdef ZFS_DEBUG
- if (labels) {
- ASSERT(offset + size <= VDEV_LABEL_START_SIZE ||
- offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
- }
-#endif
- ASSERT3U(offset + size, <=, vd->vdev_psize);
-
- BP_ZERO(bp);
-
- BP_SET_LSIZE(bp, size);
- BP_SET_PSIZE(bp, size);
-
- BP_SET_CHECKSUM(bp, checksum);
- BP_SET_COMPRESS(bp, ZIO_COMPRESS_OFF);
- BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
-
- if (checksum != ZIO_CHECKSUM_OFF)
- ZIO_SET_CHECKSUM(&bp->blk_cksum, offset, 0, 0, 0);
-}
-
zio_t *
zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
void *data, int checksum, zio_done_func_t *done, void *private,
int priority, int flags, boolean_t labels)
{
zio_t *zio;
- blkptr_t blk;
-
- ZIO_ENTER(vd->vdev_spa);
- zio_phys_bp_init(vd, &blk, offset, size, checksum, labels);
+ ASSERT(vd->vdev_children == 0);
+ ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
+ offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
+ ASSERT3U(offset + size, <=, vd->vdev_psize);
- zio = zio_create(pio, vd->vdev_spa, 0, &blk, data, size, done, private,
- ZIO_TYPE_READ, priority, flags | ZIO_FLAG_PHYSICAL,
+ zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
+ ZIO_TYPE_READ, priority, flags, vd, offset, NULL,
ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE);
- zio->io_vd = vd;
- zio->io_offset = offset;
-
- /*
- * Work off our copy of the bp so the caller can free it.
- */
- zio->io_bp = &zio->io_bp_copy;
+ zio->io_prop.zp_checksum = checksum;
return (zio);
}
@@ -736,53 +655,47 @@
void *data, int checksum, zio_done_func_t *done, void *private,
int priority, int flags, boolean_t labels)
{
- zio_block_tail_t *zbt;
- void *wbuf;
zio_t *zio;
- blkptr_t blk;
- ZIO_ENTER(vd->vdev_spa);
+ ASSERT(vd->vdev_children == 0);
+ ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
+ offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
+ ASSERT3U(offset + size, <=, vd->vdev_psize);
- zio_phys_bp_init(vd, &blk, offset, size, checksum, labels);
-
- zio = zio_create(pio, vd->vdev_spa, 0, &blk, data, size, done, private,
- ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_PHYSICAL,
+ zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
+ ZIO_TYPE_WRITE, priority, flags, vd, offset, NULL,
ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE);
- zio->io_vd = vd;
- zio->io_offset = offset;
-
- zio->io_bp = &zio->io_bp_copy;
- zio->io_checksum = checksum;
+ zio->io_prop.zp_checksum = checksum;
if (zio_checksum_table[checksum].ci_zbt) {
/*
* zbt checksums are necessarily destructive -- they modify
- * one word of the write buffer to hold the verifier/checksum.
+ * the end of the write buffer to hold the verifier/checksum.
* Therefore, we must make a local copy in case the data is
- * being written to multiple places.
+ * being written to multiple places in parallel.
*/
- wbuf = zio_buf_alloc(size);
+ void *wbuf = zio_buf_alloc(size);
bcopy(data, wbuf, size);
- zio_push_transform(zio, wbuf, size, size);
-
- zbt = (zio_block_tail_t *)((char *)wbuf + size) - 1;
- zbt->zbt_cksum = blk.blk_cksum;
+ zio_push_transform(zio, wbuf, size, size, NULL);
}
return (zio);
}
/*
- * Create a child I/O to do some work for us. It has no associated bp.
+ * Create a child I/O to do some work for us.
*/
zio_t *
-zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd, uint64_t offset,
+zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset,
void *data, uint64_t size, int type, int priority, int flags,
zio_done_func_t *done, void *private)
{
uint32_t pipeline = ZIO_VDEV_CHILD_PIPELINE;
- zio_t *cio;
+ zio_t *zio;
+
+ ASSERT(vd->vdev_parent ==
+ (pio->io_vd ? pio->io_vd : pio->io_spa->spa_root_vdev));
if (type == ZIO_TYPE_READ && bp != NULL) {
/*
@@ -792,18 +705,275 @@
* eliminates redundant checksums in the interior nodes.
*/
pipeline |= 1U << ZIO_STAGE_CHECKSUM_VERIFY;
- zio->io_pipeline &= ~(1U << ZIO_STAGE_CHECKSUM_VERIFY);
+ pio->io_pipeline &= ~(1U << ZIO_STAGE_CHECKSUM_VERIFY);
+ }
+
+ if (vd->vdev_children == 0)
+ offset += VDEV_LABEL_START_SIZE;
+
+ zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size,
+ done, private, type, priority,
+ (pio->io_flags & ZIO_FLAG_VDEV_INHERIT) |
+ ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | flags,
+ vd, offset, &pio->io_bookmark,
+ ZIO_STAGE_VDEV_IO_START - 1, pipeline);
+
+ return (zio);
+}
+
+zio_t *
+zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size,
+ int type, int priority, int flags, zio_done_func_t *done, void *private)
+{
+ zio_t *zio;
+
+ ASSERT(vd->vdev_ops->vdev_op_leaf);
+
+ zio = zio_create(NULL, vd->vdev_spa, 0, NULL,
+ data, size, done, private, type, priority,
+ flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY,
+ vd, offset, NULL,
+ ZIO_STAGE_VDEV_IO_START - 1, ZIO_VDEV_CHILD_PIPELINE);
+
+ return (zio);
+}
+
+void
+zio_flush(zio_t *zio, vdev_t *vd)
+{
+ zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE,
+ NULL, NULL, ZIO_PRIORITY_NOW,
+ ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY));
+}
+
+/*
+ * ==========================================================================
+ * Prepare to read and write logical blocks
+ * ==========================================================================
+ */
+
+static int
+zio_read_bp_init(zio_t *zio)
+{
+ blkptr_t *bp = zio->io_bp;
+
+ if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF && zio->io_logical == zio) {
+ uint64_t csize = BP_GET_PSIZE(bp);
+ void *cbuf = zio_buf_alloc(csize);
+
+ zio_push_transform(zio, cbuf, csize, csize, zio_decompress);
+ }
+
+ if (!dmu_ot[BP_GET_TYPE(bp)].ot_metadata && BP_GET_LEVEL(bp) == 0)
+ zio->io_flags |= ZIO_FLAG_DONT_CACHE;
+
+ return (ZIO_PIPELINE_CONTINUE);
+}
+
+static int
+zio_write_bp_init(zio_t *zio)
+{
+ zio_prop_t *zp = &zio->io_prop;
+ int compress = zp->zp_compress;
+ blkptr_t *bp = zio->io_bp;
+ void *cbuf;
+ uint64_t lsize = zio->io_size;
+ uint64_t csize = lsize;
+ uint64_t cbufsize = 0;
+ int pass = 1;
+
+ /*
+ * If our children haven't all reached the ready stage,
+ * wait for them and then repeat this pipeline stage.
+ */
+ if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
+ zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_READY))
+ return (ZIO_PIPELINE_STOP);
+
+ if (!IO_IS_ALLOCATING(zio))
+ return (ZIO_PIPELINE_CONTINUE);
+
+ ASSERT(compress != ZIO_COMPRESS_INHERIT);
+
+ if (bp->blk_birth == zio->io_txg) {
+ /*
+ * We're rewriting an existing block, which means we're
+ * working on behalf of spa_sync(). For spa_sync() to
+ * converge, it must eventually be the case that we don't
+ * have to allocate new blocks. But compression changes
+ * the blocksize, which forces a reallocate, and makes
+ * convergence take longer. Therefore, after the first
+ * few passes, stop compressing to ensure convergence.
+ */
+ pass = spa_sync_pass(zio->io_spa);
+ ASSERT(pass > 1);
+
+ if (pass > SYNC_PASS_DONT_COMPRESS)
+ compress = ZIO_COMPRESS_OFF;
+
+ /*
+ * Only MOS (objset 0) data should need to be rewritten.
+ */
+ ASSERT(zio->io_logical->io_bookmark.zb_objset == 0);
+
+ /* Make sure someone doesn't change their mind on overwrites */
+ ASSERT(MIN(zp->zp_ndvas + BP_IS_GANG(bp),
+ spa_max_replication(zio->io_spa)) == BP_GET_NDVAS(bp));
+ }
+
+ if (compress != ZIO_COMPRESS_OFF) {
+ if (!zio_compress_data(compress, zio->io_data, zio->io_size,
+ &cbuf, &csize, &cbufsize)) {
+ compress = ZIO_COMPRESS_OFF;
+ } else if (csize != 0) {
+ zio_push_transform(zio, cbuf, csize, cbufsize, NULL);
+ }
}
- cio = zio_create(zio, zio->io_spa, zio->io_txg, bp, data, size,
- done, private, type, priority,
- (zio->io_flags & ZIO_FLAG_VDEV_INHERIT) | ZIO_FLAG_CANFAIL | flags,
- ZIO_STAGE_VDEV_IO_START - 1, pipeline);
+ /*
+ * The final pass of spa_sync() must be all rewrites, but the first
+ * few passes offer a trade-off: allocating blocks defers convergence,
+ * but newly allocated blocks are sequential, so they can be written
+ * to disk faster. Therefore, we allow the first few passes of
+ * spa_sync() to allocate new blocks, but force rewrites after that.
+ * There should only be a handful of blocks after pass 1 in any case.
+ */
+ if (bp->blk_birth == zio->io_txg && BP_GET_PSIZE(bp) == csize &&
+ pass > SYNC_PASS_REWRITE) {
+ ASSERT(csize != 0);
+ uint32_t gang_stages = zio->io_pipeline & ZIO_GANG_STAGES;
+ zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages;
+ zio->io_flags |= ZIO_FLAG_IO_REWRITE;
+ } else {
+ BP_ZERO(bp);
+ zio->io_pipeline = ZIO_WRITE_PIPELINE;
+ }
+
+ if (csize == 0) {
+ zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
+ } else {
+ ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER);
+ BP_SET_LSIZE(bp, lsize);
+ BP_SET_PSIZE(bp, csize);
+ BP_SET_COMPRESS(bp, compress);
+ BP_SET_CHECKSUM(bp, zp->zp_checksum);
+ BP_SET_TYPE(bp, zp->zp_type);
+ BP_SET_LEVEL(bp, zp->zp_level);
+ BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
+ }
+
+ return (ZIO_PIPELINE_CONTINUE);
+}
+
+/*
+ * ==========================================================================
+ * Execute the I/O pipeline
+ * ==========================================================================
+ */
+
+static void
+zio_taskq_dispatch(zio_t *zio, enum zio_taskq_type q)
+{
+ zio_type_t t = zio->io_type;
+
+ /*
+ * If we're a config writer, the normal issue and interrupt threads
+ * may all be blocked waiting for the config lock. In this case,
+ * select the otherwise-unused taskq for ZIO_TYPE_NULL.
+ */
+ if (zio->io_flags & ZIO_FLAG_CONFIG_WRITER)
+ t = ZIO_TYPE_NULL;
+
+ /*
+ * A similar issue exists for the L2ARC write thread until L2ARC 2.0.
+ */
+ if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux)
+ t = ZIO_TYPE_NULL;
+
+ (void) taskq_dispatch(zio->io_spa->spa_zio_taskq[t][q],
+ (task_func_t *)zio_execute, zio, TQ_SLEEP);
+}
+
+static boolean_t
+zio_taskq_member(zio_t *zio, enum zio_taskq_type q)
+{
+ kthread_t *executor = zio->io_executor;
+ spa_t *spa = zio->io_spa;
- cio->io_vd = vd;
- cio->io_offset = offset;
+ for (zio_type_t t = 0; t < ZIO_TYPES; t++)
+ if (taskq_member(spa->spa_zio_taskq[t][q], executor))
+ return (B_TRUE);
+
+ return (B_FALSE);
+}
+
+static int
+zio_issue_async(zio_t *zio)
+{
+ zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE);
+
+ return (ZIO_PIPELINE_STOP);
+}
+
+void
+zio_interrupt(zio_t *zio)
+{
+ zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT);
+}
+
+/*
+ * Execute the I/O pipeline until one of the following occurs:
+ * (1) the I/O completes; (2) the pipeline stalls waiting for
+ * dependent child I/Os; (3) the I/O issues, so we're waiting
+ * for an I/O completion interrupt; (4) the I/O is delegated by
+ * vdev-level caching or aggregation; (5) the I/O is deferred
+ * due to vdev-level queueing; (6) the I/O is handed off to
+ * another thread. In all cases, the pipeline stops whenever
+ * there's no CPU work; it never burns a thread in cv_wait().
+ *
+ * There's no locking on io_stage because there's no legitimate way
+ * for multiple threads to be attempting to process the same I/O.
+ */
+static zio_pipe_stage_t *zio_pipeline[ZIO_STAGES];
- return (cio);
+void
+zio_execute(zio_t *zio)
+{
+ zio->io_executor = curthread;
+
+ while (zio->io_stage < ZIO_STAGE_DONE) {
+ uint32_t pipeline = zio->io_pipeline;
+ zio_stage_t stage = zio->io_stage;
+ int rv;
+
+ ASSERT(!MUTEX_HELD(&zio->io_lock));
+
+ while (((1U << ++stage) & pipeline) == 0)
+ continue;
+
+ ASSERT(stage <= ZIO_STAGE_DONE);
+ ASSERT(zio->io_stall == NULL);
+
+ /*
+ * If we are in interrupt context and this pipeline stage
+ * will grab a config lock that is held across I/O,
+ * issue async to avoid deadlock.
+ */
+ if (((1U << stage) & ZIO_CONFIG_LOCK_BLOCKING_STAGES) &&
+ zio->io_vd == NULL &&
+ zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) {
+ zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE);
+ return;
+ }
+
+ zio->io_stage = stage;
+ rv = zio_pipeline[stage](zio);
+
+ if (rv == ZIO_PIPELINE_STOP)
+ return;
+
+ ASSERT(rv == ZIO_PIPELINE_CONTINUE);
+ }
}
/*
@@ -811,33 +981,20 @@
* Initiate I/O, either sync or async
* ==========================================================================
*/
-static void
-zio_destroy(zio_t *zio)
-{
- mutex_destroy(&zio->io_lock);
- cv_destroy(&zio->io_cv);
- if (zio->io_failed_vds != NULL) {
- kmem_free(zio->io_failed_vds,
- zio->io_failed_vds_count * sizeof (vdev_t *));
- zio->io_failed_vds = NULL;
- zio->io_failed_vds_count = 0;
- }
- kmem_cache_free(zio_cache, zio);
-}
-
int
zio_wait(zio_t *zio)
{
int error;
ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
+ ASSERT(zio->io_executor == NULL);
zio->io_waiter = curthread;
zio_execute(zio);
mutex_enter(&zio->io_lock);
- while (zio->io_stalled != ZIO_STAGE_DONE)
+ while (zio->io_executor != NULL)
cv_wait(&zio->io_cv, &zio->io_lock);
mutex_exit(&zio->io_lock);
@@ -850,755 +1007,452 @@
void
zio_nowait(zio_t *zio)
{
+ ASSERT(zio->io_executor == NULL);
+
+ if (zio->io_parent == NULL && zio->io_child_type == ZIO_CHILD_LOGICAL) {
+ /*
+ * This is a logical async I/O with no parent to wait for it.
+ * Attach it to the pool's global async root zio so that
+ * spa_unload() has a way of waiting for async I/O to finish.
+ */
+ spa_t *spa = zio->io_spa;
+ zio->io_async_root = B_TRUE;
+ mutex_enter(&spa->spa_async_root_lock);
+ spa->spa_async_root_count++;
+ mutex_exit(&spa->spa_async_root_lock);
+ }
+
zio_execute(zio);
}
+/*
+ * ==========================================================================
+ * Reexecute or suspend/resume failed I/O
+ * ==========================================================================
+ */
+
+static void
+zio_reexecute(zio_t *pio)
+{
+ zio_t *zio, *zio_next;
+
+ pio->io_flags = pio->io_orig_flags;
+ pio->io_stage = pio->io_orig_stage;
+ pio->io_pipeline = pio->io_orig_pipeline;
+ pio->io_reexecute = 0;
+ pio->io_error = 0;
+ for (int c = 0; c < ZIO_CHILD_TYPES; c++)
+ pio->io_child_error[c] = 0;
+
+ if (IO_IS_ALLOCATING(pio)) {
+ /*
+ * Remember the failed bp so that the io_ready() callback
+ * can update its accounting upon reexecution. The block
+ * was already freed in zio_done(); we indicate this with
+ * a fill count of -1 so that zio_free() knows to skip it.
+ */
+ blkptr_t *bp = pio->io_bp;
+ ASSERT(bp->blk_birth == 0 || bp->blk_birth == pio->io_txg);
+ bp->blk_fill = BLK_FILL_ALREADY_FREED;
+ pio->io_bp_orig = *bp;
+ BP_ZERO(bp);
+ }
+
+ /*
+ * As we reexecute pio's children, new children could be created.
+ * New children go to the head of the io_child list, however,
+ * so we will (correctly) not reexecute them. The key is that
+ * the remainder of the io_child list, from 'zio_next' onward,
+ * cannot be affected by any side effects of reexecuting 'zio'.
+ */
+ for (zio = pio->io_child; zio != NULL; zio = zio_next) {
+ zio_next = zio->io_sibling_next;
+ mutex_enter(&pio->io_lock);
+ pio->io_children[zio->io_child_type][ZIO_WAIT_READY]++;
+ pio->io_children[zio->io_child_type][ZIO_WAIT_DONE]++;
+ mutex_exit(&pio->io_lock);
+ zio_reexecute(zio);
+ }
+
+ /*
+ * Now that all children have been reexecuted, execute the parent.
+ */
+ zio_execute(pio);
+}
+
void
-zio_interrupt(zio_t *zio)
+zio_suspend(spa_t *spa, zio_t *zio)
{
- (void) taskq_dispatch(zio->io_spa->spa_zio_intr_taskq[zio->io_type],
- (task_func_t *)zio_execute, zio, TQ_SLEEP);
+ if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC)
+ fm_panic("Pool '%s' has encountered an uncorrectable I/O "
+ "failure and the failure mode property for this pool "
+ "is set to panic.", spa_name(spa));
+
+ zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0);
+
+ mutex_enter(&spa->spa_suspend_lock);
+
+ if (spa->spa_suspend_zio_root == NULL)
+ spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL, 0);
+
+ spa->spa_suspended = B_TRUE;
+
+ if (zio != NULL) {
+ ASSERT(zio != spa->spa_suspend_zio_root);
+ ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
+ ASSERT(zio->io_parent == NULL);
+ ASSERT(zio->io_stage == ZIO_STAGE_DONE);
+ zio_add_child(spa->spa_suspend_zio_root, zio);
+ }
+
+ mutex_exit(&spa->spa_suspend_lock);
}
-static int
-zio_issue_async(zio_t *zio)
+void
+zio_resume(spa_t *spa)
{
- (void) taskq_dispatch(zio->io_spa->spa_zio_issue_taskq[zio->io_type],
- (task_func_t *)zio_execute, zio, TQ_SLEEP);
+ zio_t *pio, *zio;
+
+ /*
+ * Reexecute all previously suspended i/o.
+ */
+ mutex_enter(&spa->spa_suspend_lock);
+ spa->spa_suspended = B_FALSE;
+ cv_broadcast(&spa->spa_suspend_cv);
+ pio = spa->spa_suspend_zio_root;
+ spa->spa_suspend_zio_root = NULL;
+ mutex_exit(&spa->spa_suspend_lock);
+
+ if (pio == NULL)
+ return;
- return (ZIO_PIPELINE_STOP);
+ while ((zio = pio->io_child) != NULL) {
+ zio_remove_child(pio, zio);
+ zio->io_parent = NULL;
+ zio_reexecute(zio);
+ }
+
+ ASSERT(pio->io_children[ZIO_CHILD_LOGICAL][ZIO_WAIT_DONE] == 0);
+
+ (void) zio_wait(pio);
+}
+
+void
+zio_resume_wait(spa_t *spa)
+{
+ mutex_enter(&spa->spa_suspend_lock);
+ while (spa_suspended(spa))
+ cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock);
+ mutex_exit(&spa->spa_suspend_lock);
}
/*
* ==========================================================================
- * I/O pipeline interlocks: parent/child dependency scoreboarding
+ * Gang blocks.
+ *
+ * A gang block is a collection of small blocks that looks to the DMU
+ * like one large block. When zio_dva_allocate() cannot find a block
+ * of the requested size, due to either severe fragmentation or the pool
+ * being nearly full, it calls zio_write_gang_block() to construct the
+ * block from smaller fragments.
+ *
+ * A gang block consists of a gang header (zio_gbh_phys_t) and up to
+ * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like
+ * an indirect block: it's an array of block pointers. It consumes
+ * only one sector and hence is allocatable regardless of fragmentation.
+ * The gang header's bps point to its gang members, which hold the data.
+ *
+ * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg>
+ * as the verifier to ensure uniqueness of the SHA256 checksum.
+ * Critically, the gang block bp's blk_cksum is the checksum of the data,
+ * not the gang header. This ensures that data block signatures (needed for
+ * deduplication) are independent of how the block is physically stored.
+ *
+ * Gang blocks can be nested: a gang member may itself be a gang block.
+ * Thus every gang block is a tree in which root and all interior nodes are
+ * gang headers, and the leaves are normal blocks that contain user data.
+ * The root of the gang tree is called the gang leader.
+ *
+ * To perform any operation (read, rewrite, free, claim) on a gang block,
+ * zio_gang_assemble() first assembles the gang tree (minus data leaves)
+ * in the io_gang_tree field of the original logical i/o by recursively
+ * reading the gang leader and all gang headers below it. This yields
+ * an in-core tree containing the contents of every gang header and the
+ * bps for every constituent of the gang block.
+ *
+ * With the gang tree now assembled, zio_gang_issue() just walks the gang tree
+ * and invokes a callback on each bp. To free a gang block, zio_gang_issue()
+ * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp.
+ * zio_claim_gang() provides a similarly trivial wrapper for zio_claim().
+ * zio_read_gang() is a wrapper around zio_read() that omits reading gang
+ * headers, since we already have those in io_gang_tree. zio_rewrite_gang()
+ * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite()
+ * of the gang header plus zio_checksum_compute() of the data to update the
+ * gang header's blk_cksum as described above.
+ *
+ * The two-phase assemble/issue model solves the problem of partial failure --
+ * what if you'd freed part of a gang block but then couldn't read the
+ * gang header for another part? Assembling the entire gang tree first
+ * ensures that all the necessary gang header I/O has succeeded before
+ * starting the actual work of free, claim, or write. Once the gang tree
+ * is assembled, free and claim are in-memory operations that cannot fail.
+ *
+ * In the event that a gang write fails, zio_dva_unallocate() walks the
+ * gang tree to immediately free (i.e. insert back into the space map)
+ * everything we've allocated. This ensures that we don't get ENOSPC
+ * errors during repeated suspend/resume cycles due to a flaky device.
+ *
+ * Gang rewrites only happen during sync-to-convergence. If we can't assemble
+ * the gang tree, we won't modify the block, so we can safely defer the free
+ * (knowing that the block is still intact). If we *can* assemble the gang
+ * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free
+ * each constituent bp and we can allocate a new block on the next sync pass.
+ *
+ * In all cases, the gang tree allows complete recovery from partial failure.
* ==========================================================================
*/
-static int
-zio_wait_for_children(zio_t *zio, uint32_t stage, uint64_t *countp)
-{
- int rv = ZIO_PIPELINE_CONTINUE;
- mutex_enter(&zio->io_lock);
- ASSERT(zio->io_stalled == 0);
- if (*countp != 0) {
- zio->io_stalled = stage;
- rv = ZIO_PIPELINE_STOP;
- }
- mutex_exit(&zio->io_lock);
+static zio_t *
+zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
+{
+ if (gn != NULL)
+ return (pio);
- return (rv);
+ return (zio_read(pio, pio->io_spa, bp, data, BP_GET_PSIZE(bp),
+ NULL, NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
+ &pio->io_bookmark));
}
-static void
-zio_add_failed_vdev(zio_t *pio, zio_t *zio)
+zio_t *
+zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
{
- uint64_t oldcount = pio->io_failed_vds_count;
- vdev_t **new_vds;
- int i;
+ zio_t *zio;
- ASSERT(MUTEX_HELD(&pio->io_lock));
-
- if (zio->io_vd == NULL)
- return;
-
- for (i = 0; i < oldcount; i++) {
- if (pio->io_failed_vds[i] == zio->io_vd)
- return;
+ if (gn != NULL) {
+ zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
+ gn->gn_gbh, SPA_GANGBLOCKSIZE, NULL, NULL, pio->io_priority,
+ ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
+ /*
+ * As we rewrite each gang header, the pipeline will compute
+ * a new gang block header checksum for it; but no one will
+ * compute a new data checksum, so we do that here. The one
+ * exception is the gang leader: the pipeline already computed
+ * its data checksum because that stage precedes gang assembly.
+ * (Presently, nothing actually uses interior data checksums;
+ * this is just good hygiene.)
+ */
+ if (gn != pio->io_logical->io_gang_tree) {
+ zio_checksum_compute(zio, BP_GET_CHECKSUM(bp),
+ data, BP_GET_PSIZE(bp));
+ }
+ } else {
+ zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
+ data, BP_GET_PSIZE(bp), NULL, NULL, pio->io_priority,
+ ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
}
- new_vds = kmem_zalloc((oldcount + 1) * sizeof (vdev_t *), KM_SLEEP);
- if (pio->io_failed_vds != NULL) {
- bcopy(pio->io_failed_vds, new_vds,
- oldcount * sizeof (vdev_t *));
- kmem_free(pio->io_failed_vds, oldcount * sizeof (vdev_t *));
- }
- pio->io_failed_vds = new_vds;
- pio->io_failed_vds[oldcount] = zio->io_vd;
- pio->io_failed_vds_count++;
+ return (zio);
+}
+
+/* ARGSUSED */
+zio_t *
+zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
+{
+ return (zio_free(pio, pio->io_spa, pio->io_txg, bp,
+ NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)));
+}
+
+/* ARGSUSED */
+zio_t *
+zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
+{
+ return (zio_claim(pio, pio->io_spa, pio->io_txg, bp,
+ NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)));
+}
+
+static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = {
+ NULL,
+ zio_read_gang,
+ zio_rewrite_gang,
+ zio_free_gang,
+ zio_claim_gang,
+ NULL
+};
+
+static void zio_gang_tree_assemble_done(zio_t *zio);
+
+static zio_gang_node_t *
+zio_gang_node_alloc(zio_gang_node_t **gnpp)
+{
+ zio_gang_node_t *gn;
+
+ ASSERT(*gnpp == NULL);
+
+ gn = kmem_zalloc(sizeof (*gn), KM_SLEEP);
+ gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE);
+ *gnpp = gn;
+
+ return (gn);
}
static void
-zio_notify_parent(zio_t *zio, uint32_t stage, uint64_t *countp)
+zio_gang_node_free(zio_gang_node_t **gnpp)
+{
+ zio_gang_node_t *gn = *gnpp;
+
+ for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
+ ASSERT(gn->gn_child[g] == NULL);
+
+ zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE);
+ kmem_free(gn, sizeof (*gn));
+ *gnpp = NULL;
+}
+
+static void
+zio_gang_tree_free(zio_gang_node_t **gnpp)
{
- zio_t *pio = zio->io_parent;
+ zio_gang_node_t *gn = *gnpp;
+
+ if (gn == NULL)
+ return;
+
+ for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
+ zio_gang_tree_free(&gn->gn_child[g]);
+
+ zio_gang_node_free(gnpp);
+}
+
+static void
+zio_gang_tree_assemble(zio_t *lio, blkptr_t *bp, zio_gang_node_t **gnpp)
+{
+ zio_gang_node_t *gn = zio_gang_node_alloc(gnpp);
- mutex_enter(&pio->io_lock);
- if (pio->io_error == 0 && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE)) {
- pio->io_error = zio->io_error;
- if (zio->io_error && zio->io_error != ENOTSUP)
- zio_add_failed_vdev(pio, zio);
- }
- ASSERT3U(*countp, >, 0);
- if (--*countp == 0 && pio->io_stalled == stage) {
- pio->io_stalled = 0;
- mutex_exit(&pio->io_lock);
- zio_execute(pio);
- } else {
- mutex_exit(&pio->io_lock);
+ ASSERT(lio->io_logical == lio);
+ ASSERT(BP_IS_GANG(bp));
+
+ zio_nowait(zio_read(lio, lio->io_spa, bp, gn->gn_gbh,
+ SPA_GANGBLOCKSIZE, zio_gang_tree_assemble_done, gn,
+ lio->io_priority, ZIO_GANG_CHILD_FLAGS(lio), &lio->io_bookmark));
+}
+
+static void
+zio_gang_tree_assemble_done(zio_t *zio)
+{
+ zio_t *lio = zio->io_logical;
+ zio_gang_node_t *gn = zio->io_private;
+ blkptr_t *bp = zio->io_bp;
+
+ ASSERT(zio->io_parent == lio);
+ ASSERT(zio->io_child == NULL);
+
+ if (zio->io_error)
+ return;
+
+ if (BP_SHOULD_BYTESWAP(bp))
+ byteswap_uint64_array(zio->io_data, zio->io_size);
+
+ ASSERT(zio->io_data == gn->gn_gbh);
+ ASSERT(zio->io_size == SPA_GANGBLOCKSIZE);
+ ASSERT(gn->gn_gbh->zg_tail.zbt_magic == ZBT_MAGIC);
+
+ for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
+ blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
+ if (!BP_IS_GANG(gbp))
+ continue;
+ zio_gang_tree_assemble(lio, gbp, &gn->gn_child[g]);
}
}
-int
-zio_wait_for_children_ready(zio_t *zio)
+static void
+zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, void *data)
{
- return (zio_wait_for_children(zio, ZIO_STAGE_WAIT_FOR_CHILDREN_READY,
- &zio->io_children_notready));
-}
+ zio_t *lio = pio->io_logical;
+ zio_t *zio;
+
+ ASSERT(BP_IS_GANG(bp) == !!gn);
+ ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(lio->io_bp));
+ ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == lio->io_gang_tree);
+
+ /*
+ * If you're a gang header, your data is in gn->gn_gbh.
+ * If you're a gang member, your data is in 'data' and gn == NULL.
+ */
+ zio = zio_gang_issue_func[lio->io_type](pio, bp, gn, data);
-int
-zio_wait_for_children_done(zio_t *zio)
-{
- return (zio_wait_for_children(zio, ZIO_STAGE_WAIT_FOR_CHILDREN_DONE,
- &zio->io_children_notdone));
+ if (gn != NULL) {
+ ASSERT(gn->gn_gbh->zg_tail.zbt_magic == ZBT_MAGIC);
+
+ for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
+ blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
+ if (BP_IS_HOLE(gbp))
+ continue;
+ zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data);
+ data = (char *)data + BP_GET_PSIZE(gbp);
+ }
+ }
+
+ if (gn == lio->io_gang_tree)
+ ASSERT3P((char *)lio->io_data + lio->io_size, ==, data);
+
+ if (zio != pio)
+ zio_nowait(zio);
}
static int
-zio_read_init(zio_t *zio)
+zio_gang_assemble(zio_t *zio)
{
blkptr_t *bp = zio->io_bp;
- if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF) {
- uint64_t csize = BP_GET_PSIZE(bp);
- void *cbuf = zio_buf_alloc(csize);
-
- zio_push_transform(zio, cbuf, csize, csize);
- zio->io_pipeline |= 1U << ZIO_STAGE_READ_DECOMPRESS;
- }
-
- if (BP_IS_GANG(bp)) {
- uint64_t gsize = SPA_GANGBLOCKSIZE;
- void *gbuf = zio_buf_alloc(gsize);
-
- zio_push_transform(zio, gbuf, gsize, gsize);
- zio->io_pipeline |= 1U << ZIO_STAGE_READ_GANG_MEMBERS;
- }
+ ASSERT(BP_IS_GANG(bp) && zio == zio->io_logical);
- if (!dmu_ot[BP_GET_TYPE(bp)].ot_metadata && BP_GET_LEVEL(bp) == 0)
- zio->io_flags |= ZIO_FLAG_DONT_CACHE;
-
- return (ZIO_PIPELINE_CONTINUE);
-}
-
-static int
-zio_ready(zio_t *zio)
-{
- zio_t *pio = zio->io_parent;
-
- if (zio->io_ready)
- zio->io_ready(zio);
-
- if (pio != NULL)
- zio_notify_parent(zio, ZIO_STAGE_WAIT_FOR_CHILDREN_READY,
- &pio->io_children_notready);
-
- if (zio->io_bp)
- zio->io_bp_copy = *zio->io_bp;
+ zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree);
return (ZIO_PIPELINE_CONTINUE);
}
static int
-zio_vdev_retry_io(zio_t *zio)
-{
- zio_t *pio = zio->io_parent;
-
- /*
- * Preserve the failed bp so that the io_ready() callback can
- * update the accounting accordingly. The callback will also be
- * responsible for freeing the previously allocated block, if one
- * exists.
- */
- zio->io_bp_orig = *zio->io_bp;
-
- /*
- * We must zero out the old DVA and blk_birth before reallocating
- * the bp.
- */
- BP_ZERO_DVAS(zio->io_bp);
- zio_reset(zio);
-
- if (pio) {
- /*
- * Let the parent know that we will
- * re-alloc the write (=> new bp info).
- */
- mutex_enter(&pio->io_lock);
- pio->io_children_notready++;
-
- /*
- * If the parent I/O is still in the open stage, then
- * don't bother telling it to retry since it hasn't
- * progressed far enough for it to care.
- */
- if (pio->io_stage > ZIO_STAGE_OPEN && IO_IS_ALLOCATING(pio))
- pio->io_flags |= ZIO_FLAG_WRITE_RETRY;
-
- ASSERT(pio->io_stage <= ZIO_STAGE_WAIT_FOR_CHILDREN_DONE);
- mutex_exit(&pio->io_lock);
- }
-
- /*
- * We are getting ready to process the retry request so clear
- * the flag and the zio's current error status.
- */
- zio->io_flags &= ~ZIO_FLAG_WRITE_RETRY;
- zio->io_error = 0;
-
- return (ZIO_PIPELINE_CONTINUE);
-}
-
-int
-zio_vdev_resume_io(spa_t *spa)
-{
- zio_t *zio;
-
- mutex_enter(&spa->spa_zio_lock);
-
- /*
- * Probe all of vdevs that have experienced an I/O error.
- * If we are still unable to verify the integrity of the vdev
- * then we prevent the resume from proceeeding.
- */
- for (zio = list_head(&spa->spa_zio_list); zio != NULL;
- zio = list_next(&spa->spa_zio_list, zio)) {
- int error = 0;
-
- /* We only care about I/Os that must succeed */
- if (zio->io_vd == NULL || zio->io_flags & ZIO_FLAG_CANFAIL)
- continue;
- error = vdev_probe(zio->io_vd);
- if (error) {
- mutex_exit(&spa->spa_zio_lock);
- return (error);
- }
- }
-
- /*
- * Clear the vdev stats so that I/O can flow.
- */
- vdev_clear(spa, NULL, B_FALSE);
-
- spa->spa_state = POOL_STATE_ACTIVE;
- while ((zio = list_head(&spa->spa_zio_list)) != NULL) {
- list_remove(&spa->spa_zio_list, zio);
- zio->io_error = 0;
-
- /*
- * If we are resuming an allocating I/O then we force it
- * to retry and let it resume operation where it left off.
- * Otherwise, go back to the ready stage and pick up from
- * there.
- */
- if (zio_write_retry && IO_IS_ALLOCATING(zio)) {
- zio->io_flags |= ZIO_FLAG_WRITE_RETRY;
- zio->io_stage--;
- } else {
- zio->io_stage = ZIO_STAGE_READY;
- }
-
- (void) taskq_dispatch(zio_taskq, (task_func_t *)zio_execute,
- zio, TQ_SLEEP);
- }
- mutex_exit(&spa->spa_zio_lock);
-
- /*
- * Wait for the taskqs to finish and recheck the pool state since
- * it's possible that a resumed I/O has failed again.
- */
- taskq_wait(zio_taskq);
- if (spa_state(spa) == POOL_STATE_IO_FAILURE)
- return (EIO);
-
- mutex_enter(&spa->spa_zio_lock);
- cv_broadcast(&spa->spa_zio_cv);
- mutex_exit(&spa->spa_zio_lock);
-
- return (0);
-}
-
-static int
-zio_vdev_suspend_io(zio_t *zio)
-{
- spa_t *spa = zio->io_spa;
-
- /*
- * We've experienced an unrecoverable failure so
- * set the pool state accordingly and queue all
- * failed IOs.
- */
- spa->spa_state = POOL_STATE_IO_FAILURE;
-
- mutex_enter(&spa->spa_zio_lock);
- list_insert_tail(&spa->spa_zio_list, zio);
-
-#ifndef _KERNEL
- /* Used to notify ztest that the pool has suspended */
- cv_broadcast(&spa->spa_zio_cv);
-#endif
- mutex_exit(&spa->spa_zio_lock);
-
- return (ZIO_PIPELINE_STOP);
-}
-
-static void
-zio_handle_io_failure(zio_t *zio, vdev_t *vd)
+zio_gang_issue(zio_t *zio)
{
- spa_t *spa = zio->io_spa;
+ zio_t *lio = zio->io_logical;
blkptr_t *bp = zio->io_bp;
- char *blkbuf;
-
-#ifdef ZFS_DEBUG
- blkbuf = kmem_alloc(BP_SPRINTF_LEN, KM_NOSLEEP);
- if (blkbuf) {
- sprintf_blkptr(blkbuf, BP_SPRINTF_LEN,
- bp ? bp : &zio->io_bp_copy);
- }
- cmn_err(CE_WARN, "ZFS: %s (%s on %s off %llx: zio %p %s): error %d",
- zio->io_error == ECKSUM ? "bad checksum" : "I/O failure",
- zio_type_name[zio->io_type], vdev_description(vd),
- (u_longlong_t)zio->io_offset, (void *)zio,
- blkbuf ? blkbuf : "", zio->io_error);
- if (blkbuf)
- kmem_free(blkbuf, BP_SPRINTF_LEN);
-#endif
-
- if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC) {
- fm_panic("Pool '%s' has encountered an uncorrectable I/O "
- "failure and the failure mode property for this pool "
- "is set to panic.", spa_name(spa));
- }
- zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0);
- vdev_set_state(vd, vd == spa->spa_root_vdev ? B_TRUE : B_FALSE,
- VDEV_STATE_FAULTED, VDEV_AUX_IO_FAILURE);
-}
-
-static int
-zio_assess(zio_t *zio)
-{
- spa_t *spa = zio->io_spa;
- blkptr_t *bp = zio->io_bp;
- vdev_t *vd = zio->io_vd;
-
- ASSERT(zio->io_children_notready == 0);
- ASSERT(zio->io_children_notdone == 0);
-
- if (bp != NULL) {
- ASSERT(bp->blk_pad[0] == 0);
- ASSERT(bp->blk_pad[1] == 0);
- ASSERT(bp->blk_pad[2] == 0);
- ASSERT(bcmp(bp, &zio->io_bp_copy, sizeof (blkptr_t)) == 0);
- if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(bp) &&
- !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) {
- ASSERT(!BP_SHOULD_BYTESWAP(bp));
- if (zio->io_ndvas != 0)
- ASSERT3U(zio->io_ndvas, <=, BP_GET_NDVAS(bp));
- ASSERT(BP_COUNT_GANG(bp) == 0 ||
- (BP_COUNT_GANG(bp) == BP_GET_NDVAS(bp)));
- }
- }
-
- /*
- * Some child I/O has indicated that a retry is necessary, so
- * we set an error on the I/O and let the logic below do the
- * rest.
- */
- if (zio->io_flags & ZIO_FLAG_WRITE_RETRY)
- zio->io_error = ERESTART;
-
- if (vd != NULL)
- vdev_stat_update(zio);
- if (zio->io_error) {
- /*
- * If this I/O is attached to a particular vdev,
- * generate an error message describing the I/O failure
- * at the block level. We ignore these errors if the
- * device is currently unavailable.
- */
- if (zio->io_error != ECKSUM && vd != NULL && !vdev_is_dead(vd))
- zfs_ereport_post(FM_EREPORT_ZFS_IO, spa, vd, zio, 0, 0);
-
- if ((zio->io_error == EIO ||
- !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) &&
- zio->io_logical == zio) {
- /*
- * For root I/O requests, tell the SPA to log the error
- * appropriately. Also, generate a logical data
- * ereport.
- */
- spa_log_error(spa, zio);
-
- zfs_ereport_post(FM_EREPORT_ZFS_DATA, spa, NULL, zio,
- 0, 0);
- }
-
- /*
- * If we are an allocating I/O then we attempt to reissue
- * the I/O on another vdev unless the pool is out of space.
- * We handle this condition based on the spa's failmode
- * property.
- */
- if (zio_write_retry && zio->io_error != ENOSPC &&
- IO_IS_ALLOCATING(zio))
- return (zio_vdev_retry_io(zio));
-
- ASSERT(!(zio->io_flags & ZIO_FLAG_WRITE_RETRY));
-
- /*
- * For I/O requests that cannot fail, we carry out
- * the requested behavior based on the failmode pool
- * property.
- *
- * XXX - Need to differentiate between an ENOSPC as
- * a result of vdev failures vs. a full pool.
- */
- if (!(zio->io_flags & ZIO_FLAG_CANFAIL)) {
- int i;
-
- for (i = 0; i < zio->io_failed_vds_count; i++) {
- zio_handle_io_failure(zio,
- zio->io_failed_vds[i]);
- }
- if (zio->io_failed_vds_count == 0) {
- zio_handle_io_failure(zio,
- vd ? vd : spa->spa_root_vdev);
- }
- if (zio->io_failed_vds != NULL) {
- kmem_free(zio->io_failed_vds,
- zio->io_failed_vds_count *
- sizeof (vdev_t *));
- zio->io_failed_vds = NULL;
- zio->io_failed_vds_count = 0;
- }
- return (zio_vdev_suspend_io(zio));
- }
- }
- ASSERT(!(zio->io_flags & ZIO_FLAG_WRITE_RETRY));
- ASSERT(zio->io_children_notready == 0);
-
- return (ZIO_PIPELINE_CONTINUE);
-}
-
-static int
-zio_done(zio_t *zio)
-{
- zio_t *pio = zio->io_parent;
- spa_t *spa = zio->io_spa;
-
- ASSERT(zio->io_children_notready == 0);
- ASSERT(zio->io_children_notdone == 0);
+ if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE))
+ return (ZIO_PIPELINE_STOP);
- zio_clear_transform_stack(zio);
-
- if (zio->io_done)
- zio->io_done(zio);
-
- ASSERT(zio->io_delegate_list == NULL);
- ASSERT(zio->io_delegate_next == NULL);
-
- if (pio != NULL) {
- zio_t *next, *prev;
-
- mutex_enter(&pio->io_lock);
- next = zio->io_sibling_next;
- prev = zio->io_sibling_prev;
- if (next != NULL)
- next->io_sibling_prev = prev;
- if (prev != NULL)
- prev->io_sibling_next = next;
- if (pio->io_child == zio)
- pio->io_child = next;
- mutex_exit(&pio->io_lock);
-
- zio_notify_parent(zio, ZIO_STAGE_WAIT_FOR_CHILDREN_DONE,
- &pio->io_children_notdone);
- }
-
- /*
- * Note: this I/O is now done, and will shortly be freed, so there is no
- * need to clear this (or any other) flag.
- */
- if (zio->io_flags & ZIO_FLAG_CONFIG_GRABBED)
- spa_config_exit(spa, zio);
-
- if (zio->io_waiter != NULL) {
- mutex_enter(&zio->io_lock);
- ASSERT(zio->io_stage == ZIO_STAGE_DONE);
- zio->io_stalled = zio->io_stage;
- cv_broadcast(&zio->io_cv);
- mutex_exit(&zio->io_lock);
- } else {
- zio_destroy(zio);
- }
-
- return (ZIO_PIPELINE_STOP);
-}
-
-/*
- * ==========================================================================
- * Compression support
- * ==========================================================================
- */
-static int
-zio_write_compress(zio_t *zio)
-{
- int compress = zio->io_compress;
- blkptr_t *bp = zio->io_bp;
- void *cbuf;
- uint64_t lsize = zio->io_size;
- uint64_t csize = lsize;
- uint64_t cbufsize = 0;
- int pass;
-
- if (bp->blk_birth == zio->io_txg) {
- /*
- * We're rewriting an existing block, which means we're
- * working on behalf of spa_sync(). For spa_sync() to
- * converge, it must eventually be the case that we don't
- * have to allocate new blocks. But compression changes
- * the blocksize, which forces a reallocate, and makes
- * convergence take longer. Therefore, after the first
- * few passes, stop compressing to ensure convergence.
- */
- pass = spa_sync_pass(zio->io_spa);
- if (pass > zio_sync_pass.zp_dontcompress)
- compress = ZIO_COMPRESS_OFF;
- } else {
- ASSERT(BP_IS_HOLE(bp));
- pass = 1;
- }
-
- if (compress != ZIO_COMPRESS_OFF)
- if (!zio_compress_data(compress, zio->io_data, zio->io_size,
- &cbuf, &csize, &cbufsize))
- compress = ZIO_COMPRESS_OFF;
-
- if (compress != ZIO_COMPRESS_OFF && csize != 0)
- zio_push_transform(zio, cbuf, csize, cbufsize);
-
- /*
- * The final pass of spa_sync() must be all rewrites, but the first
- * few passes offer a trade-off: allocating blocks defers convergence,
- * but newly allocated blocks are sequential, so they can be written
- * to disk faster. Therefore, we allow the first few passes of
- * spa_sync() to reallocate new blocks, but force rewrites after that.
- * There should only be a handful of blocks after pass 1 in any case.
- */
- if (bp->blk_birth == zio->io_txg && BP_GET_PSIZE(bp) == csize &&
- pass > zio_sync_pass.zp_rewrite) {
- ASSERT(csize != 0);
- BP_SET_LSIZE(bp, lsize);
- BP_SET_COMPRESS(bp, compress);
- zio->io_pipeline = ZIO_REWRITE_PIPELINE(bp);
- } else {
- if (bp->blk_birth == zio->io_txg)
- BP_ZERO(bp);
- if (csize == 0) {
- BP_ZERO(bp);
- zio->io_pipeline = ZIO_WAIT_FOR_CHILDREN_PIPELINE;
- } else {
- ASSERT3U(BP_GET_NDVAS(bp), ==, 0);
- BP_SET_LSIZE(bp, lsize);
- BP_SET_PSIZE(bp, csize);
- BP_SET_COMPRESS(bp, compress);
- }
- }
-
- return (ZIO_PIPELINE_CONTINUE);
-}
-
-static int
-zio_read_decompress(zio_t *zio)
-{
- blkptr_t *bp = zio->io_bp;
- void *data;
- uint64_t size;
- uint64_t bufsize;
- int compress = BP_GET_COMPRESS(bp);
-
- ASSERT(compress != ZIO_COMPRESS_OFF);
-
- zio_pop_transform(zio, &data, &size, &bufsize);
-
- if (zio_decompress_data(compress, data, size,
- zio->io_data, zio->io_size))
- zio->io_error = EIO;
-
- zio_buf_free(data, bufsize);
-
- return (ZIO_PIPELINE_CONTINUE);
-}
+ ASSERT(BP_IS_GANG(bp) && zio == lio);
-/*
- * ==========================================================================
- * Gang block support
- * ==========================================================================
- */
-static void
-zio_gang_byteswap(zio_t *zio)
-{
- ASSERT(zio->io_size == SPA_GANGBLOCKSIZE);
-
- if (BP_SHOULD_BYTESWAP(zio->io_bp))
- byteswap_uint64_array(zio->io_data, zio->io_size);
-}
-
-static int
-zio_get_gang_header(zio_t *zio)
-{
- blkptr_t *bp = zio->io_bp;
- uint64_t gsize = SPA_GANGBLOCKSIZE;
- void *gbuf = zio_buf_alloc(gsize);
-
- ASSERT(BP_IS_GANG(bp));
-
- zio_push_transform(zio, gbuf, gsize, gsize);
-
- zio_nowait(zio_create(zio, zio->io_spa, bp->blk_birth, bp, gbuf, gsize,
- NULL, NULL, ZIO_TYPE_READ, zio->io_priority,
- zio->io_flags & ZIO_FLAG_GANG_INHERIT,
- ZIO_STAGE_OPEN, ZIO_READ_GANG_PIPELINE));
-
- return (zio_wait_for_children_done(zio));
-}
-
-static int
-zio_read_gang_members(zio_t *zio)
-{
- zio_gbh_phys_t *gbh;
- uint64_t gsize, gbufsize, loff, lsize;
- int i;
-
- ASSERT(BP_IS_GANG(zio->io_bp));
-
- zio_gang_byteswap(zio);
- zio_pop_transform(zio, (void **)&gbh, &gsize, &gbufsize);
-
- for (loff = 0, i = 0; loff != zio->io_size; loff += lsize, i++) {
- blkptr_t *gbp = &gbh->zg_blkptr[i];
- lsize = BP_GET_PSIZE(gbp);
-
- ASSERT(BP_GET_COMPRESS(gbp) == ZIO_COMPRESS_OFF);
- ASSERT3U(lsize, ==, BP_GET_LSIZE(gbp));
- ASSERT3U(loff + lsize, <=, zio->io_size);
- ASSERT(i < SPA_GBH_NBLKPTRS);
- ASSERT(!BP_IS_HOLE(gbp));
-
- zio_nowait(zio_read(zio, zio->io_spa, gbp,
- (char *)zio->io_data + loff, lsize,
- NULL, NULL, zio->io_priority,
- zio->io_flags & ZIO_FLAG_GANG_INHERIT, &zio->io_bookmark));
- }
-
- zio_buf_free(gbh, gbufsize);
-
- return (zio_wait_for_children_done(zio));
-}
-
-static int
-zio_rewrite_gang_members(zio_t *zio)
-{
- zio_gbh_phys_t *gbh;
- uint64_t gsize, gbufsize, loff, lsize;
- int i;
+ if (zio->io_child_error[ZIO_CHILD_GANG] == 0)
+ zio_gang_tree_issue(lio, lio->io_gang_tree, bp, lio->io_data);
+ else
+ zio_gang_tree_free(&lio->io_gang_tree);
- ASSERT(BP_IS_GANG(zio->io_bp));
- ASSERT3U(zio->io_size, ==, SPA_GANGBLOCKSIZE);
-
- zio_gang_byteswap(zio);
- zio_pop_transform(zio, (void **)&gbh, &gsize, &gbufsize);
-
- ASSERT(gsize == gbufsize);
-
- for (loff = 0, i = 0; loff != zio->io_size; loff += lsize, i++) {
- blkptr_t *gbp = &gbh->zg_blkptr[i];
- lsize = BP_GET_PSIZE(gbp);
-
- ASSERT(BP_GET_COMPRESS(gbp) == ZIO_COMPRESS_OFF);
- ASSERT3U(lsize, ==, BP_GET_LSIZE(gbp));
- ASSERT3U(loff + lsize, <=, zio->io_size);
- ASSERT(i < SPA_GBH_NBLKPTRS);
- ASSERT(!BP_IS_HOLE(gbp));
-
- zio_nowait(zio_rewrite(zio, zio->io_spa, zio->io_checksum,
- zio->io_txg, gbp, (char *)zio->io_data + loff, lsize,
- NULL, NULL, zio->io_priority,
- zio->io_flags & ZIO_FLAG_GANG_INHERIT, &zio->io_bookmark));
- }
-
- zio_push_transform(zio, gbh, gsize, gbufsize);
-
- return (zio_wait_for_children_ready(zio));
-}
-
-static int
-zio_free_gang_members(zio_t *zio)
-{
- zio_gbh_phys_t *gbh;
- uint64_t gsize, gbufsize;
- int i;
-
- ASSERT(BP_IS_GANG(zio->io_bp));
-
- zio_gang_byteswap(zio);
- zio_pop_transform(zio, (void **)&gbh, &gsize, &gbufsize);
-
- for (i = 0; i < SPA_GBH_NBLKPTRS; i++) {
- blkptr_t *gbp = &gbh->zg_blkptr[i];
-
- if (BP_IS_HOLE(gbp))
- continue;
- zio_nowait(zio_free(zio, zio->io_spa, zio->io_txg,
- gbp, NULL, NULL));
- }
-
- zio_buf_free(gbh, gbufsize);
-
- return (ZIO_PIPELINE_CONTINUE);
-}
-
-static int
-zio_claim_gang_members(zio_t *zio)
-{
- zio_gbh_phys_t *gbh;
- uint64_t gsize, gbufsize;
- int i;
-
- ASSERT(BP_IS_GANG(zio->io_bp));
-
- zio_gang_byteswap(zio);
- zio_pop_transform(zio, (void **)&gbh, &gsize, &gbufsize);
-
- for (i = 0; i < SPA_GBH_NBLKPTRS; i++) {
- blkptr_t *gbp = &gbh->zg_blkptr[i];
- if (BP_IS_HOLE(gbp))
- continue;
- zio_nowait(zio_claim(zio, zio->io_spa, zio->io_txg,
- gbp, NULL, NULL));
- }
-
- zio_buf_free(gbh, gbufsize);
+ zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
return (ZIO_PIPELINE_CONTINUE);
}
static void
-zio_write_allocate_gang_member_done(zio_t *zio)
+zio_write_gang_member_ready(zio_t *zio)
{
zio_t *pio = zio->io_parent;
+ zio_t *lio = zio->io_logical;
dva_t *cdva = zio->io_bp->blk_dva;
dva_t *pdva = pio->io_bp->blk_dva;
uint64_t asize;
- int d;
+
+ if (BP_IS_HOLE(zio->io_bp))
+ return;
+
+ ASSERT(BP_IS_HOLE(&zio->io_bp_orig));
- ASSERT3U(pio->io_ndvas, ==, zio->io_ndvas);
+ ASSERT(zio->io_child_type == ZIO_CHILD_GANG);
+ ASSERT3U(zio->io_prop.zp_ndvas, ==, lio->io_prop.zp_ndvas);
+ ASSERT3U(zio->io_prop.zp_ndvas, <=, BP_GET_NDVAS(zio->io_bp));
+ ASSERT3U(pio->io_prop.zp_ndvas, <=, BP_GET_NDVAS(pio->io_bp));
ASSERT3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp));
- ASSERT3U(zio->io_ndvas, <=, BP_GET_NDVAS(zio->io_bp));
- ASSERT3U(pio->io_ndvas, <=, BP_GET_NDVAS(pio->io_bp));
mutex_enter(&pio->io_lock);
- for (d = 0; d < BP_GET_NDVAS(pio->io_bp); d++) {
+ for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) {
ASSERT(DVA_GET_GANG(&pdva[d]));
asize = DVA_GET_ASIZE(&pdva[d]);
asize += DVA_GET_ASIZE(&cdva[d]);
@@ -1608,99 +1462,76 @@
}
static int
-zio_write_allocate_gang_members(zio_t *zio, metaslab_class_t *mc)
+zio_write_gang_block(zio_t *pio)
{
- blkptr_t *bp = zio->io_bp;
- dva_t *dva = bp->blk_dva;
- spa_t *spa = zio->io_spa;
+ spa_t *spa = pio->io_spa;
+ blkptr_t *bp = pio->io_bp;
+ zio_t *lio = pio->io_logical;
+ zio_t *zio;
+ zio_gang_node_t *gn, **gnpp;
zio_gbh_phys_t *gbh;
- uint64_t txg = zio->io_txg;
- uint64_t resid = zio->io_size;
- uint64_t maxalloc = P2ROUNDUP(zio->io_size >> 1, SPA_MINBLOCKSIZE);
- uint64_t gsize, loff, lsize;
- uint32_t gbps_left;
- int ndvas = zio->io_ndvas;
+ uint64_t txg = pio->io_txg;
+ uint64_t resid = pio->io_size;
+ uint64_t lsize;
+ int ndvas = lio->io_prop.zp_ndvas;
int gbh_ndvas = MIN(ndvas + 1, spa_max_replication(spa));
+ zio_prop_t zp;
int error;
- int i, d;
- gsize = SPA_GANGBLOCKSIZE;
- gbps_left = SPA_GBH_NBLKPTRS;
-
- error = metaslab_alloc(spa, mc, gsize, bp, gbh_ndvas, txg, NULL,
- B_FALSE);
+ error = metaslab_alloc(spa, spa->spa_normal_class, SPA_GANGBLOCKSIZE,
+ bp, gbh_ndvas, txg, pio == lio ? NULL : lio->io_bp,
+ METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER);
if (error) {
- zio->io_error = error;
+ pio->io_error = error;
return (ZIO_PIPELINE_CONTINUE);
}
- for (d = 0; d < gbh_ndvas; d++)
- DVA_SET_GANG(&dva[d], 1);
-
- bp->blk_birth = txg;
-
- gbh = zio_buf_alloc(gsize);
- bzero(gbh, gsize);
-
- for (loff = 0, i = 0; loff != zio->io_size;
- loff += lsize, resid -= lsize, gbps_left--, i++) {
- blkptr_t *gbp = &gbh->zg_blkptr[i];
- dva = gbp->blk_dva;
-
- ASSERT(gbps_left != 0);
- maxalloc = MIN(maxalloc, resid);
-
- while (resid <= maxalloc * gbps_left) {
- error = metaslab_alloc(spa, mc, maxalloc, gbp, ndvas,
- txg, bp, B_FALSE);
- if (error == 0)
- break;
- ASSERT3U(error, ==, ENOSPC);
- /* XXX - free up previous allocations? */
- if (maxalloc == SPA_MINBLOCKSIZE) {
- zio->io_error = error;
- return (ZIO_PIPELINE_CONTINUE);
- }
- maxalloc = P2ROUNDUP(maxalloc >> 1, SPA_MINBLOCKSIZE);
- }
-
- if (resid <= maxalloc * gbps_left) {
- lsize = maxalloc;
- BP_SET_LSIZE(gbp, lsize);
- BP_SET_PSIZE(gbp, lsize);
- BP_SET_COMPRESS(gbp, ZIO_COMPRESS_OFF);
- gbp->blk_birth = txg;
- zio_nowait(zio_rewrite(zio, spa, zio->io_checksum, txg,
- gbp, (char *)zio->io_data + loff, lsize,
- zio_write_allocate_gang_member_done, NULL,
- zio->io_priority,
- zio->io_flags & ZIO_FLAG_GANG_INHERIT,
- &zio->io_bookmark));
- } else {
- lsize = P2ROUNDUP(resid / gbps_left, SPA_MINBLOCKSIZE);
- ASSERT(lsize != SPA_MINBLOCKSIZE);
- zio_nowait(zio_write_allocate(zio, spa,
- zio->io_checksum, txg, gbp,
- (char *)zio->io_data + loff, lsize,
- zio_write_allocate_gang_member_done, NULL,
- zio->io_priority,
- zio->io_flags & ZIO_FLAG_GANG_INHERIT));
- }
+ if (pio == lio) {
+ gnpp = &lio->io_gang_tree;
+ } else {
+ gnpp = pio->io_private;
+ ASSERT(pio->io_ready == zio_write_gang_member_ready);
}
- ASSERT(resid == 0 && loff == zio->io_size);
+ gn = zio_gang_node_alloc(gnpp);
+ gbh = gn->gn_gbh;
+ bzero(gbh, SPA_GANGBLOCKSIZE);
- zio->io_pipeline |= 1U << ZIO_STAGE_GANG_CHECKSUM_GENERATE;
-
- zio_push_transform(zio, gbh, gsize, gsize);
+ /*
+ * Create the gang header.
+ */
+ zio = zio_rewrite(pio, spa, txg, bp, gbh, SPA_GANGBLOCKSIZE, NULL, NULL,
+ pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
/*
- * As much as we'd like this to be 'ready' instead of 'done',
- * updating our ASIZE doesn't happen until the io_done callback,
- * so we have to wait for that to finish in order for our BP
- * to be stable.
+ * Create and nowait the gang children.
*/
- return (zio_wait_for_children_done(zio));
+ for (int g = 0; resid != 0; resid -= lsize, g++) {
+ lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g),
+ SPA_MINBLOCKSIZE);
+ ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid);
+
+ zp.zp_checksum = lio->io_prop.zp_checksum;
+ zp.zp_compress = ZIO_COMPRESS_OFF;
+ zp.zp_type = DMU_OT_NONE;
+ zp.zp_level = 0;
+ zp.zp_ndvas = lio->io_prop.zp_ndvas;
+
+ zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g],
+ (char *)pio->io_data + (pio->io_size - resid), lsize, &zp,
+ zio_write_gang_member_ready, NULL, &gn->gn_child[g],
+ pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
+ &pio->io_bookmark));
+ }
+
+ /*
+ * Set pio's pipeline to just wait for zio to finish.
+ */
+ pio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
+
+ zio_nowait(zio);
+
+ return (ZIO_PIPELINE_CONTINUE);
}
/*
@@ -1708,6 +1539,7 @@
* Allocate and free blocks
* ==========================================================================
*/
+
static int
zio_dva_allocate(zio_t *zio)
{
@@ -1718,29 +1550,16 @@
ASSERT(BP_IS_HOLE(bp));
ASSERT3U(BP_GET_NDVAS(bp), ==, 0);
- ASSERT3U(zio->io_ndvas, >, 0);
- ASSERT3U(zio->io_ndvas, <=, spa_max_replication(spa));
-
- /*
- * For testing purposes, we force I/Os to retry. We don't allow
- * retries beyond the first pass since those I/Os are non-allocating
- * writes.
- */
- if (zio_io_fail_shift &&
- spa_sync_pass(zio->io_spa) <= zio_sync_pass.zp_rewrite &&
- zio_io_should_fail(zio_io_fail_shift))
- zio->io_flags |= ZIO_FLAG_WRITE_RETRY;
-
+ ASSERT3U(zio->io_prop.zp_ndvas, >, 0);
+ ASSERT3U(zio->io_prop.zp_ndvas, <=, spa_max_replication(spa));
ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp));
- error = metaslab_alloc(spa, mc, zio->io_size, bp, zio->io_ndvas,
- zio->io_txg, NULL, B_FALSE);
+ error = metaslab_alloc(spa, mc, zio->io_size, bp,
+ zio->io_prop.zp_ndvas, zio->io_txg, NULL, 0);
- if (error == 0) {
- bp->blk_birth = zio->io_txg;
- } else if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE) {
- return (zio_write_allocate_gang_members(zio, mc));
- } else {
+ if (error) {
+ if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE)
+ return (zio_write_gang_block(zio));
zio->io_error = error;
}
@@ -1750,11 +1569,7 @@
static int
zio_dva_free(zio_t *zio)
{
- blkptr_t *bp = zio->io_bp;
-
- metaslab_free(zio->io_spa, bp, zio->io_txg, B_FALSE);
-
- BP_ZERO(bp);
+ metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE);
return (ZIO_PIPELINE_CONTINUE);
}
@@ -1762,145 +1577,325 @@
static int
zio_dva_claim(zio_t *zio)
{
- zio->io_error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg);
+ int error;
+
+ error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg);
+ if (error)
+ zio->io_error = error;
return (ZIO_PIPELINE_CONTINUE);
}
/*
+ * Undo an allocation. This is used by zio_done() when an I/O fails
+ * and we want to give back the block we just allocated.
+ * This handles both normal blocks and gang blocks.
+ */
+static void
+zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp)
+{
+ spa_t *spa = zio->io_spa;
+ boolean_t now = !(zio->io_flags & ZIO_FLAG_IO_REWRITE);
+
+ ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp));
+
+ if (zio->io_bp == bp && !now) {
+ /*
+ * This is a rewrite for sync-to-convergence.
+ * We can't do a metaslab_free(NOW) because bp wasn't allocated
+ * during this sync pass, which means that metaslab_sync()
+ * already committed the allocation.
+ */
+ ASSERT(DVA_EQUAL(BP_IDENTITY(bp),
+ BP_IDENTITY(&zio->io_bp_orig)));
+ ASSERT(spa_sync_pass(spa) > 1);
+
+ if (BP_IS_GANG(bp) && gn == NULL) {
+ /*
+ * This is a gang leader whose gang header(s) we
+ * couldn't read now, so defer the free until later.
+ * The block should still be intact because without
+ * the headers, we'd never even start the rewrite.
+ */
+ bplist_enqueue_deferred(&spa->spa_sync_bplist, bp);
+ return;
+ }
+ }
+
+ if (!BP_IS_HOLE(bp))
+ metaslab_free(spa, bp, bp->blk_birth, now);
+
+ if (gn != NULL) {
+ for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
+ zio_dva_unallocate(zio, gn->gn_child[g],
+ &gn->gn_gbh->zg_blkptr[g]);
+ }
+ }
+}
+
+/*
+ * Try to allocate an intent log block. Return 0 on success, errno on failure.
+ */
+int
+zio_alloc_blk(spa_t *spa, uint64_t size, blkptr_t *new_bp, blkptr_t *old_bp,
+ uint64_t txg)
+{
+ int error;
+
+ error = metaslab_alloc(spa, spa->spa_log_class, size,
+ new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID);
+
+ if (error)
+ error = metaslab_alloc(spa, spa->spa_normal_class, size,
+ new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID);
+
+ if (error == 0) {
+ BP_SET_LSIZE(new_bp, size);
+ BP_SET_PSIZE(new_bp, size);
+ BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF);
+ BP_SET_CHECKSUM(new_bp, ZIO_CHECKSUM_ZILOG);
+ BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG);
+ BP_SET_LEVEL(new_bp, 0);
+ BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER);
+ }
+
+ return (error);
+}
+
+/*
+ * Free an intent log block. We know it can't be a gang block, so there's
+ * nothing to do except metaslab_free() it.
+ */
+void
+zio_free_blk(spa_t *spa, blkptr_t *bp, uint64_t txg)
+{
+ ASSERT(!BP_IS_GANG(bp));
+
+ metaslab_free(spa, bp, txg, B_FALSE);
+}
+
+/*
* ==========================================================================
* Read and write to physical devices
* ==========================================================================
*/
+static void
+zio_vdev_io_probe_done(zio_t *zio)
+{
+ zio_t *dio;
+ vdev_t *vd = zio->io_private;
+
+ mutex_enter(&vd->vdev_probe_lock);
+ ASSERT(vd->vdev_probe_zio == zio);
+ vd->vdev_probe_zio = NULL;
+ mutex_exit(&vd->vdev_probe_lock);
+
+ while ((dio = zio->io_delegate_list) != NULL) {
+ zio->io_delegate_list = dio->io_delegate_next;
+ dio->io_delegate_next = NULL;
+ if (!vdev_accessible(vd, dio))
+ dio->io_error = ENXIO;
+ zio_execute(dio);
+ }
+}
+
+/*
+ * Probe the device to determine whether I/O failure is specific to this
+ * zio (e.g. a bad sector) or affects the entire vdev (e.g. unplugged).
+ */
+static int
+zio_vdev_io_probe(zio_t *zio)
+{
+ vdev_t *vd = zio->io_vd;
+ zio_t *pio = NULL;
+ boolean_t created_pio = B_FALSE;
+
+ /*
+ * Don't probe the probe.
+ */
+ if (zio->io_flags & ZIO_FLAG_PROBE)
+ return (ZIO_PIPELINE_CONTINUE);
+
+ /*
+ * To prevent 'probe storms' when a device fails, we create
+ * just one probe i/o at a time. All zios that want to probe
+ * this vdev will join the probe zio's io_delegate_list.
+ */
+ mutex_enter(&vd->vdev_probe_lock);
+
+ if ((pio = vd->vdev_probe_zio) == NULL) {
+ vd->vdev_probe_zio = pio = zio_root(zio->io_spa,
+ zio_vdev_io_probe_done, vd, ZIO_FLAG_CANFAIL);
+ created_pio = B_TRUE;
+ vd->vdev_probe_wanted = B_TRUE;
+ spa_async_request(zio->io_spa, SPA_ASYNC_PROBE);
+ }
+
+ zio->io_delegate_next = pio->io_delegate_list;
+ pio->io_delegate_list = zio;
+
+ mutex_exit(&vd->vdev_probe_lock);
+
+ if (created_pio) {
+ zio_nowait(vdev_probe(vd, pio));
+ zio_nowait(pio);
+ }
+
+ return (ZIO_PIPELINE_STOP);
+}
+
static int
zio_vdev_io_start(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
- vdev_t *tvd = vd ? vd->vdev_top : NULL;
- blkptr_t *bp = zio->io_bp;
uint64_t align;
spa_t *spa = zio->io_spa;
- /*
- * If the pool is already in a failure state then just suspend
- * this IO until the problem is resolved. We will reissue them
- * at that time.
- */
- if (spa_state(spa) == POOL_STATE_IO_FAILURE &&
- zio->io_type == ZIO_TYPE_WRITE)
- return (zio_vdev_suspend_io(zio));
+ ASSERT(zio->io_error == 0);
+ ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0);
+
+ if (vd == NULL) {
+ if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
+ spa_config_enter(spa, SCL_ZIO, zio, RW_READER);
- /*
- * The mirror_ops handle multiple DVAs in a single BP
- */
- if (vd == NULL)
+ /*
+ * The mirror_ops handle multiple DVAs in a single BP.
+ */
return (vdev_mirror_ops.vdev_op_io_start(zio));
-
- align = 1ULL << tvd->vdev_ashift;
+ }
- if (zio->io_retries == 0 && vd == tvd)
- zio->io_flags |= ZIO_FLAG_FAILFAST;
-
- if (!(zio->io_flags & ZIO_FLAG_PHYSICAL) && vd->vdev_children == 0) {
- zio->io_flags |= ZIO_FLAG_PHYSICAL;
- zio->io_offset += VDEV_LABEL_START_SIZE;
- }
+ align = 1ULL << vd->vdev_top->vdev_ashift;
if (P2PHASE(zio->io_size, align) != 0) {
uint64_t asize = P2ROUNDUP(zio->io_size, align);
char *abuf = zio_buf_alloc(asize);
- ASSERT(vd == tvd);
+ ASSERT(vd == vd->vdev_top);
if (zio->io_type == ZIO_TYPE_WRITE) {
bcopy(zio->io_data, abuf, zio->io_size);
bzero(abuf + zio->io_size, asize - zio->io_size);
}
- zio_push_transform(zio, abuf, asize, asize);
- ASSERT(!(zio->io_flags & ZIO_FLAG_SUBBLOCK));
- zio->io_flags |= ZIO_FLAG_SUBBLOCK;
+ zio_push_transform(zio, abuf, asize, asize, zio_subblock);
}
ASSERT(P2PHASE(zio->io_offset, align) == 0);
ASSERT(P2PHASE(zio->io_size, align) == 0);
- ASSERT(bp == NULL ||
- P2ROUNDUP(ZIO_GET_IOSIZE(zio), align) == zio->io_size);
ASSERT(zio->io_type != ZIO_TYPE_WRITE || (spa_mode & FWRITE));
+ if (vd->vdev_ops->vdev_op_leaf &&
+ (zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE)) {
+
+ if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio) == 0)
+ return (ZIO_PIPELINE_STOP);
+
+ if ((zio = vdev_queue_io(zio)) == NULL)
+ return (ZIO_PIPELINE_STOP);
+
+ if (!vdev_accessible(vd, zio)) {
+ zio->io_error = ENXIO;
+ zio_interrupt(zio);
+ return (ZIO_PIPELINE_STOP);
+ }
+
+ }
+
return (vd->vdev_ops->vdev_op_io_start(zio));
}
static int
zio_vdev_io_done(zio_t *zio)
{
- if (zio->io_vd == NULL)
- return (vdev_mirror_ops.vdev_op_io_done(zio));
+ vdev_t *vd = zio->io_vd;
+ vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops;
+ boolean_t unexpected_error = B_FALSE;
- return (zio->io_vd->vdev_ops->vdev_op_io_done(zio));
-}
+ if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
+ return (ZIO_PIPELINE_STOP);
+
+ ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
-/* XXPOLICY */
-boolean_t
-zio_should_retry(zio_t *zio)
-{
- vdev_t *vd = zio->io_vd;
+ if (vd != NULL && vd->vdev_ops->vdev_op_leaf) {
+
+ vdev_queue_io_done(zio);
+
+ if (zio->io_type == ZIO_TYPE_WRITE)
+ vdev_cache_write(zio);
+
+ if (zio_injection_enabled && zio->io_error == 0)
+ zio->io_error = zio_handle_device_injection(vd, EIO);
- if (zio->io_error == 0)
- return (B_FALSE);
- if (zio->io_delegate_list != NULL)
- return (B_FALSE);
- if (vd != NULL) {
- if (vd != vd->vdev_top)
- return (B_FALSE);
- if (vd->vdev_is_failing)
- return (B_FALSE);
+ if (zio_injection_enabled && zio->io_error == 0)
+ zio->io_error = zio_handle_label_injection(zio, EIO);
+
+ if (zio->io_error) {
+ if (!vdev_accessible(vd, zio)) {
+ zio->io_error = ENXIO;
+ } else {
+ unexpected_error = B_TRUE;
+ }
+ }
}
- if (zio->io_flags & ZIO_FLAG_DONT_RETRY)
- return (B_FALSE);
- if (zio->io_retries > 0)
- return (B_FALSE);
+
+ ops->vdev_op_io_done(zio);
- return (B_TRUE);
+ if (unexpected_error)
+ return (zio_vdev_io_probe(zio));
+
+ return (ZIO_PIPELINE_CONTINUE);
}
static int
zio_vdev_io_assess(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
- vdev_t *tvd = vd ? vd->vdev_top : NULL;
- ASSERT(zio->io_vsd == NULL);
+ if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
+ return (ZIO_PIPELINE_STOP);
- if (zio->io_flags & ZIO_FLAG_SUBBLOCK) {
- void *abuf;
- uint64_t asize;
- ASSERT(vd == tvd);
- zio_pop_transform(zio, &abuf, &asize, &asize);
- if (zio->io_type == ZIO_TYPE_READ)
- bcopy(abuf, zio->io_data, zio->io_size);
- zio_buf_free(abuf, asize);
- zio->io_flags &= ~ZIO_FLAG_SUBBLOCK;
+ if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
+ spa_config_exit(zio->io_spa, SCL_ZIO, zio);
+
+ if (zio->io_vsd != NULL) {
+ zio->io_vsd_free(zio);
+ zio->io_vsd = NULL;
}
- if (zio_injection_enabled && !zio->io_error)
+ if (zio_injection_enabled && zio->io_error == 0)
zio->io_error = zio_handle_fault_injection(zio, EIO);
/*
* If the I/O failed, determine whether we should attempt to retry it.
*/
- /* XXPOLICY */
- if (zio_should_retry(zio)) {
- ASSERT(tvd == vd);
-
- zio->io_retries++;
+ if (zio->io_error && vd == NULL &&
+ !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) {
+ ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */
+ ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */
zio->io_error = 0;
- zio->io_flags &= ZIO_FLAG_RETRY_INHERIT;
- /* XXPOLICY */
- zio->io_flags &= ~ZIO_FLAG_FAILFAST;
- zio->io_flags |= ZIO_FLAG_DONT_CACHE;
+ zio->io_flags |= ZIO_FLAG_IO_RETRY |
+ ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_AGGREGATE;
zio->io_stage = ZIO_STAGE_VDEV_IO_START - 1;
+ zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE);
+ return (ZIO_PIPELINE_STOP);
+ }
- return (ZIO_PIPELINE_CONTINUE);
- }
+ /*
+ * If we got an error on a leaf device, convert it to ENXIO
+ * if the device is not accessible at all.
+ */
+ if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf &&
+ !vdev_accessible(vd, zio))
+ zio->io_error = ENXIO;
+
+ /*
+ * If we can't write to an interior vdev (mirror or RAID-Z),
+ * set vdev_cant_write so that we stop trying to allocate from it.
+ */
+ if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE &&
+ vd != NULL && !vd->vdev_ops->vdev_op_leaf)
+ vd->vdev_cant_write = B_TRUE;
+
+ if (zio->io_error)
+ zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
return (ZIO_PIPELINE_CONTINUE);
}
@@ -1940,31 +1935,30 @@
static int
zio_checksum_generate(zio_t *zio)
{
- int checksum = zio->io_checksum;
blkptr_t *bp = zio->io_bp;
-
- ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp));
+ enum zio_checksum checksum;
- BP_SET_CHECKSUM(bp, checksum);
- BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
-
- zio_checksum(checksum, &bp->blk_cksum, zio->io_data, zio->io_size);
-
- return (ZIO_PIPELINE_CONTINUE);
-}
+ if (bp == NULL) {
+ /*
+ * This is zio_write_phys().
+ * We're either generating a label checksum, or none at all.
+ */
+ checksum = zio->io_prop.zp_checksum;
-static int
-zio_gang_checksum_generate(zio_t *zio)
-{
- zio_cksum_t zc;
- zio_gbh_phys_t *gbh = zio->io_data;
+ if (checksum == ZIO_CHECKSUM_OFF)
+ return (ZIO_PIPELINE_CONTINUE);
- ASSERT(BP_IS_GANG(zio->io_bp));
- ASSERT3U(zio->io_size, ==, SPA_GANGBLOCKSIZE);
+ ASSERT(checksum == ZIO_CHECKSUM_LABEL);
+ } else {
+ if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) {
+ ASSERT(!IO_IS_ALLOCATING(zio));
+ checksum = ZIO_CHECKSUM_GANG_HEADER;
+ } else {
+ checksum = BP_GET_CHECKSUM(bp);
+ }
+ }
- zio_set_gang_verifier(zio, &gbh->zg_tail.zbt_cksum);
-
- zio_checksum(ZIO_CHECKSUM_GANG_HEADER, &zc, zio->io_data, zio->io_size);
+ zio_checksum_compute(zio, checksum, zio->io_data, zio->io_size);
return (ZIO_PIPELINE_CONTINUE);
}
@@ -1972,11 +1966,26 @@
static int
zio_checksum_verify(zio_t *zio)
{
- if (zio->io_bp != NULL) {
- zio->io_error = zio_checksum_error(zio);
- if (zio->io_error && !(zio->io_flags & ZIO_FLAG_SPECULATIVE))
+ blkptr_t *bp = zio->io_bp;
+ int error;
+
+ if (bp == NULL) {
+ /*
+ * This is zio_read_phys().
+ * We're either verifying a label checksum, or nothing at all.
+ */
+ if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF)
+ return (ZIO_PIPELINE_CONTINUE);
+
+ ASSERT(zio->io_prop.zp_checksum == ZIO_CHECKSUM_LABEL);
+ }
+
+ if ((error = zio_checksum_error(zio)) != 0) {
+ zio->io_error = error;
+ if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
zfs_ereport_post(FM_EREPORT_ZFS_CHECKSUM,
zio->io_spa, zio->io_vd, zio, 0, 0);
+ }
}
return (ZIO_PIPELINE_CONTINUE);
@@ -1992,173 +2001,263 @@
}
/*
- * Set the external verifier for a gang block based on stuff in the bp
+ * ==========================================================================
+ * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other.
+ * An error of 0 indictes success. ENXIO indicates whole-device failure,
+ * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO
+ * indicate errors that are specific to one I/O, and most likely permanent.
+ * Any other error is presumed to be worse because we weren't expecting it.
+ * ==========================================================================
*/
-void
-zio_set_gang_verifier(zio_t *zio, zio_cksum_t *zcp)
+int
+zio_worst_error(int e1, int e2)
{
- blkptr_t *bp = zio->io_bp;
+ static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO };
+ int r1, r2;
- zcp->zc_word[0] = DVA_GET_VDEV(BP_IDENTITY(bp));
- zcp->zc_word[1] = DVA_GET_OFFSET(BP_IDENTITY(bp));
- zcp->zc_word[2] = bp->blk_birth;
- zcp->zc_word[3] = 0;
+ for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++)
+ if (e1 == zio_error_rank[r1])
+ break;
+
+ for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++)
+ if (e2 == zio_error_rank[r2])
+ break;
+
+ return (r1 > r2 ? e1 : e2);
}
/*
* ==========================================================================
- * Define the pipeline
+ * I/O completion
* ==========================================================================
*/
-typedef int zio_pipe_stage_t(zio_t *zio);
+static int
+zio_ready(zio_t *zio)
+{
+ blkptr_t *bp = zio->io_bp;
+ zio_t *pio = zio->io_parent;
+
+ if (zio->io_ready) {
+ if (BP_IS_GANG(bp) &&
+ zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY))
+ return (ZIO_PIPELINE_STOP);
+
+ ASSERT(IO_IS_ALLOCATING(zio));
+ ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp));
+ ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0);
+
+ zio->io_ready(zio);
+ }
+
+ if (bp != NULL && bp != &zio->io_bp_copy)
+ zio->io_bp_copy = *bp;
+
+ if (zio->io_error)
+ zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
+
+ if (pio != NULL)
+ zio_notify_parent(pio, zio, ZIO_WAIT_READY);
+
+ return (ZIO_PIPELINE_CONTINUE);
+}
+
+static int
+zio_done(zio_t *zio)
+{
+ spa_t *spa = zio->io_spa;
+ zio_t *pio = zio->io_parent;
+ zio_t *lio = zio->io_logical;
+ blkptr_t *bp = zio->io_bp;
+ vdev_t *vd = zio->io_vd;
+ uint64_t psize = zio->io_size;
+
+ /*
+ * If our of children haven't all completed,
+ * wait for them and then repeat this pipeline stage.
+ */
+ if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE) ||
+ zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE) ||
+ zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE))
+ return (ZIO_PIPELINE_STOP);
+
+ for (int c = 0; c < ZIO_CHILD_TYPES; c++)
+ for (int w = 0; w < ZIO_WAIT_TYPES; w++)
+ ASSERT(zio->io_children[c][w] == 0);
+
+ if (bp != NULL) {
+ ASSERT(bp->blk_pad[0] == 0);
+ ASSERT(bp->blk_pad[1] == 0);
+ ASSERT(bp->blk_pad[2] == 0);
+ ASSERT(bcmp(bp, &zio->io_bp_copy, sizeof (blkptr_t)) == 0 ||
+ (pio != NULL && bp == pio->io_bp));
+ if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(bp) &&
+ !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) {
+ ASSERT(!BP_SHOULD_BYTESWAP(bp));
+ ASSERT3U(zio->io_prop.zp_ndvas, <=, BP_GET_NDVAS(bp));
+ ASSERT(BP_COUNT_GANG(bp) == 0 ||
+ (BP_COUNT_GANG(bp) == BP_GET_NDVAS(bp)));
+ }
+ }
+
+ /*
+ * If there were child vdev or gang errors, they apply to us now.
+ */
+ zio_inherit_child_errors(zio, ZIO_CHILD_VDEV);
+ zio_inherit_child_errors(zio, ZIO_CHILD_GANG);
+
+ zio_pop_transforms(zio); /* note: may set zio->io_error */
+
+ vdev_stat_update(zio, psize);
+
+ if (zio->io_error) {
+ /*
+ * If this I/O is attached to a particular vdev,
+ * generate an error message describing the I/O failure
+ * at the block level. We ignore these errors if the
+ * device is currently unavailable.
+ */
+ if (zio->io_error != ECKSUM && vd != NULL && !vdev_is_dead(vd))
+ zfs_ereport_post(FM_EREPORT_ZFS_IO, spa, vd, zio, 0, 0);
+
+ if ((zio->io_error == EIO ||
+ !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) && zio == lio) {
+ /*
+ * For logical I/O requests, tell the SPA to log the
+ * error and generate a logical data ereport.
+ */
+ spa_log_error(spa, zio);
+ zfs_ereport_post(FM_EREPORT_ZFS_DATA, spa, NULL, zio,
+ 0, 0);
+ }
+ }
+
+ if (zio->io_error && zio == lio) {
+ /*
+ * Determine whether zio should be reexecuted. This will
+ * propagate all the way to the root via zio_notify_parent().
+ */
+ ASSERT(vd == NULL && bp != NULL);
-zio_pipe_stage_t *zio_pipeline[ZIO_STAGE_DONE + 2] = {
+ if (IO_IS_ALLOCATING(zio))
+ if (zio->io_error != ENOSPC)
+ zio->io_reexecute |= ZIO_REEXECUTE_NOW;
+ else
+ zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
+
+ if ((zio->io_type == ZIO_TYPE_READ ||
+ zio->io_type == ZIO_TYPE_FREE) &&
+ zio->io_error == ENXIO &&
+ spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE)
+ zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
+
+ if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute)
+ zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
+ }
+
+ /*
+ * If there were logical child errors, they apply to us now.
+ * We defer this until now to avoid conflating logical child
+ * errors with errors that happened to the zio itself when
+ * updating vdev stats and reporting FMA events above.
+ */
+ zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL);
+
+ if (zio->io_reexecute) {
+ /*
+ * This is a logical I/O that wants to reexecute.
+ *
+ * Reexecute is top-down. When an i/o fails, if it's not
+ * the root, it simply notifies its parent and sticks around.
+ * The parent, seeing that it still has children in zio_done(),
+ * does the same. This percolates all the way up to the root.
+ * The root i/o will reexecute or suspend the entire tree.
+ *
+ * This approach ensures that zio_reexecute() honors
+ * all the original i/o dependency relationships, e.g.
+ * parents not executing until children are ready.
+ */
+ ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
+
+ if (IO_IS_ALLOCATING(zio))
+ zio_dva_unallocate(zio, zio->io_gang_tree, bp);
+
+ zio_gang_tree_free(&zio->io_gang_tree);
+
+ if (pio != NULL) {
+ /*
+ * We're not a root i/o, so there's nothing to do
+ * but notify our parent. Don't propagate errors
+ * upward since we haven't permanently failed yet.
+ */
+ zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE;
+ zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
+ } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) {
+ /*
+ * We'd fail again if we reexecuted now, so suspend
+ * until conditions improve (e.g. device comes online).
+ */
+ zio_suspend(spa, zio);
+ } else {
+ /*
+ * Reexecution is potentially a huge amount of work.
+ * Hand it off to the otherwise-unused claim taskq.
+ */
+ (void) taskq_dispatch(
+ spa->spa_zio_taskq[ZIO_TYPE_CLAIM][ZIO_TASKQ_ISSUE],
+ (task_func_t *)zio_reexecute, zio, TQ_SLEEP);
+ }
+ return (ZIO_PIPELINE_STOP);
+ }
+
+ ASSERT(zio->io_child == NULL);
+ ASSERT(zio->io_reexecute == 0);
+ ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL));
+
+ if (zio->io_done)
+ zio->io_done(zio);
+
+ zio_gang_tree_free(&zio->io_gang_tree);
+
+ ASSERT(zio->io_delegate_list == NULL);
+ ASSERT(zio->io_delegate_next == NULL);
+
+ if (pio != NULL) {
+ zio_remove_child(pio, zio);
+ zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
+ }
+
+ if (zio->io_waiter != NULL) {
+ mutex_enter(&zio->io_lock);
+ zio->io_executor = NULL;
+ cv_broadcast(&zio->io_cv);
+ mutex_exit(&zio->io_lock);
+ } else {
+ zio_destroy(zio);
+ }
+
+ return (ZIO_PIPELINE_STOP);
+}
+
+/*
+ * ==========================================================================
+ * I/O pipeline definition
+ * ==========================================================================
+ */
+static zio_pipe_stage_t *zio_pipeline[ZIO_STAGES] = {
NULL,
- zio_wait_for_children_ready,
- zio_read_init,
zio_issue_async,
- zio_write_compress,
+ zio_read_bp_init,
+ zio_write_bp_init,
zio_checksum_generate,
- zio_get_gang_header,
- zio_rewrite_gang_members,
- zio_free_gang_members,
- zio_claim_gang_members,
+ zio_gang_assemble,
+ zio_gang_issue,
zio_dva_allocate,
zio_dva_free,
zio_dva_claim,
- zio_gang_checksum_generate,
zio_ready,
zio_vdev_io_start,
zio_vdev_io_done,
zio_vdev_io_assess,
- zio_wait_for_children_done,
zio_checksum_verify,
- zio_read_gang_members,
- zio_read_decompress,
- zio_assess,
- zio_done,
- NULL
+ zio_done
};
-
-/*
- * Execute the I/O pipeline until one of the following occurs:
- * (1) the I/O completes; (2) the pipeline stalls waiting for
- * dependent child I/Os; (3) the I/O issues, so we're waiting
- * for an I/O completion interrupt; (4) the I/O is delegated by
- * vdev-level caching or aggregation; (5) the I/O is deferred
- * due to vdev-level queueing; (6) the I/O is handed off to
- * another thread. In all cases, the pipeline stops whenever
- * there's no CPU work; it never burns a thread in cv_wait().
- *
- * There's no locking on io_stage because there's no legitimate way
- * for multiple threads to be attempting to process the same I/O.
- */
-void
-zio_execute(zio_t *zio)
-{
- while (zio->io_stage < ZIO_STAGE_DONE) {
- uint32_t pipeline = zio->io_pipeline;
- int rv;
-
- ASSERT(!MUTEX_HELD(&zio->io_lock));
-
- /*
- * If an error occurred outside the vdev stack,
- * just execute the interlock stages to clean up.
- */
- if (zio->io_error &&
- ((1U << zio->io_stage) & ZIO_VDEV_IO_STAGES) == 0)
- pipeline &= ZIO_ERROR_PIPELINE_MASK;
-
- while (((1U << ++zio->io_stage) & pipeline) == 0)
- continue;
-
- ASSERT(zio->io_stage <= ZIO_STAGE_DONE);
- ASSERT(zio->io_stalled == 0);
-
- rv = zio_pipeline[zio->io_stage](zio);
-
- if (rv == ZIO_PIPELINE_STOP)
- return;
-
- ASSERT(rv == ZIO_PIPELINE_CONTINUE);
- }
-}
-
-static boolean_t
-zio_io_should_fail(uint16_t range)
-{
- static uint16_t allocs = 0;
-
- return (P2PHASE(allocs++, 1U<<range) == 0);
-}
-
-/*
- * Try to allocate an intent log block. Return 0 on success, errno on failure.
- */
-int
-zio_alloc_blk(spa_t *spa, uint64_t size, blkptr_t *new_bp, blkptr_t *old_bp,
- uint64_t txg)
-{
- int error;
-
- spa_config_enter(spa, RW_READER, FTAG);
-
- if (zio_zil_fail_shift && zio_io_should_fail(zio_zil_fail_shift)) {
- spa_config_exit(spa, FTAG);
- return (ENOSPC);
- }
-
- /*
- * We were passed the previous log block's DVA in bp->blk_dva[0].
- * We use that as a hint for which vdev to allocate from next.
- */
- error = metaslab_alloc(spa, spa->spa_log_class, size,
- new_bp, 1, txg, old_bp, B_TRUE);
-
- if (error)
- error = metaslab_alloc(spa, spa->spa_normal_class, size,
- new_bp, 1, txg, old_bp, B_TRUE);
-
- if (error == 0) {
- BP_SET_LSIZE(new_bp, size);
- BP_SET_PSIZE(new_bp, size);
- BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF);
- BP_SET_CHECKSUM(new_bp, ZIO_CHECKSUM_ZILOG);
- BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG);
- BP_SET_LEVEL(new_bp, 0);
- BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER);
- new_bp->blk_birth = txg;
- }
-
- spa_config_exit(spa, FTAG);
-
- return (error);
-}
-
-/*
- * Free an intent log block. We know it can't be a gang block, so there's
- * nothing to do except metaslab_free() it.
- */
-void
-zio_free_blk(spa_t *spa, blkptr_t *bp, uint64_t txg)
-{
- ASSERT(!BP_IS_GANG(bp));
-
- spa_config_enter(spa, RW_READER, FTAG);
-
- metaslab_free(spa, bp, txg, B_FALSE);
-
- spa_config_exit(spa, FTAG);
-}
-
-/*
- * start an async flush of the write cache for this vdev
- */
-void
-zio_flush(zio_t *zio, vdev_t *vd)
-{
- zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE,
- NULL, NULL, ZIO_PRIORITY_NOW,
- ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY));
-}