*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
uint64_t td_objset;
blkptr_t *td_rootbp;
uint64_t td_min_txg;
+ zbookmark_t *td_resume;
int td_flags;
prefetch_data_t *td_pfd;
blkptr_cb_t *td_func;
void *td_arg;
} traverse_data_t;
-typedef struct traverse_visitbp_data {
- /* Function arguments */
- traverse_data_t *tv_td;
- const dnode_phys_t *tv_dnp;
- arc_buf_t *tv_pbuf;
- blkptr_t *tv_bp;
- const zbookmark_t *tv_zb;
- /* Local variables */
- prefetch_data_t *tv_pd;
- zbookmark_t tv_czb;
- arc_buf_t *tv_buf;
- boolean_t tv_hard;
- objset_phys_t *tv_osp;
- dnode_phys_t *tv_ldnp;
- blkptr_t *tv_cbp;
- uint32_t tv_flags;
- int tv_err;
- int tv_lasterr;
- int tv_i;
- int tv_epb;
- int tv_depth;
-} traverse_visitbp_data_t;
-
-static inline int traverse_visitbp(traverse_data_t *td, const
- dnode_phys_t *dnp, arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb);
static int traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp,
arc_buf_t *buf, uint64_t objset, uint64_t object);
zil_free(zilog);
}
-#define TRAVERSE_VISITBP_MAX_DEPTH 20
+typedef enum resume_skip {
+ RESUME_SKIP_ALL,
+ RESUME_SKIP_NONE,
+ RESUME_SKIP_CHILDREN
+} resume_skip_t;
+
+/*
+ * Returns RESUME_SKIP_ALL if td indicates that we are resuming a traversal and
+ * the block indicated by zb does not need to be visited at all. Returns
+ * RESUME_SKIP_CHILDREN if we are resuming a post traversal and we reach the
+ * resume point. This indicates that this block should be visited but not its
+ * children (since they must have been visited in a previous traversal).
+ * Otherwise returns RESUME_SKIP_NONE.
+ */
+static resume_skip_t
+resume_skip_check(traverse_data_t *td, const dnode_phys_t *dnp,
+ const zbookmark_t *zb)
+{
+ if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) {
+ /*
+ * If we already visited this bp & everything below,
+ * don't bother doing it again.
+ */
+ if (zbookmark_is_before(dnp, zb, td->td_resume))
+ return (RESUME_SKIP_ALL);
+
+ /*
+ * If we found the block we're trying to resume from, zero
+ * the bookmark out to indicate that we have resumed.
+ */
+ ASSERT3U(zb->zb_object, <=, td->td_resume->zb_object);
+ if (bcmp(zb, td->td_resume, sizeof (*zb)) == 0) {
+ bzero(td->td_resume, sizeof (*zb));
+ if (td->td_flags & TRAVERSE_POST)
+ return (RESUME_SKIP_CHILDREN);
+ }
+ }
+ return (RESUME_SKIP_NONE);
+}
static void
-__traverse_visitbp_init(traverse_visitbp_data_t *tv,
- traverse_data_t *td, const dnode_phys_t *dnp,
- arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb, int depth)
+traverse_pause(traverse_data_t *td, const zbookmark_t *zb)
{
- tv->tv_td = td;
- tv->tv_dnp = dnp;
- tv->tv_pbuf = pbuf;
- tv->tv_bp = bp;
- tv->tv_zb = zb;
- tv->tv_err = 0;
- tv->tv_lasterr = 0;
- tv->tv_buf = NULL;
- tv->tv_pd = td->td_pfd;
- tv->tv_hard = td->td_flags & TRAVERSE_HARD;
- tv->tv_flags = ARC_WAIT;
- tv->tv_depth = depth;
+ ASSERT(td->td_resume != NULL);
+ ASSERT0(zb->zb_level);
+ bcopy(zb, td->td_resume, sizeof (*td->td_resume));
}
-static noinline int
-__traverse_visitbp(traverse_visitbp_data_t *tv)
+static int
+traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp,
+ arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb)
{
- ASSERT3S(tv->tv_depth, <, TRAVERSE_VISITBP_MAX_DEPTH);
+ zbookmark_t czb;
+ int err = 0, lasterr = 0;
+ arc_buf_t *buf = NULL;
+ prefetch_data_t *pd = td->td_pfd;
+ boolean_t hard = td->td_flags & TRAVERSE_HARD;
+ boolean_t pause = B_FALSE;
+
+ switch (resume_skip_check(td, dnp, zb)) {
+ case RESUME_SKIP_ALL:
+ return (0);
+ case RESUME_SKIP_CHILDREN:
+ goto post;
+ case RESUME_SKIP_NONE:
+ break;
+ default:
+ ASSERT(0);
+ }
- if (tv->tv_bp->blk_birth == 0) {
- tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL, NULL,
- tv->tv_pbuf, tv->tv_zb, tv->tv_dnp, tv->tv_td->td_arg);
- return (tv->tv_err);
+ if (BP_IS_HOLE(bp)) {
+ err = td->td_func(td->td_spa, NULL, NULL, pbuf, zb, dnp,
+ td->td_arg);
+ return (err);
}
- if (tv->tv_bp->blk_birth <= tv->tv_td->td_min_txg)
+ if (bp->blk_birth <= td->td_min_txg)
return (0);
- if (tv->tv_pd && !tv->tv_pd->pd_exited &&
- ((tv->tv_pd->pd_flags & TRAVERSE_PREFETCH_DATA) ||
- BP_GET_TYPE(tv->tv_bp) == DMU_OT_DNODE ||
- BP_GET_LEVEL(tv->tv_bp) > 0)) {
- mutex_enter(&tv->tv_pd->pd_mtx);
- ASSERT(tv->tv_pd->pd_blks_fetched >= 0);
- while (tv->tv_pd->pd_blks_fetched == 0 && !tv->tv_pd->pd_exited)
- cv_wait(&tv->tv_pd->pd_cv, &tv->tv_pd->pd_mtx);
- tv->tv_pd->pd_blks_fetched--;
- cv_broadcast(&tv->tv_pd->pd_cv);
- mutex_exit(&tv->tv_pd->pd_mtx);
+ if (pd && !pd->pd_exited &&
+ ((pd->pd_flags & TRAVERSE_PREFETCH_DATA) ||
+ BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) {
+ mutex_enter(&pd->pd_mtx);
+ ASSERT(pd->pd_blks_fetched >= 0);
+ while (pd->pd_blks_fetched == 0 && !pd->pd_exited)
+ cv_wait(&pd->pd_cv, &pd->pd_mtx);
+ pd->pd_blks_fetched--;
+ cv_broadcast(&pd->pd_cv);
+ mutex_exit(&pd->pd_mtx);
}
- if (tv->tv_td->td_flags & TRAVERSE_PRE) {
- tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL,
- tv->tv_bp, tv->tv_pbuf, tv->tv_zb, tv->tv_dnp,
- tv->tv_td->td_arg);
- if (tv->tv_err == TRAVERSE_VISIT_NO_CHILDREN)
+ if (td->td_flags & TRAVERSE_PRE) {
+ err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp,
+ td->td_arg);
+ if (err == TRAVERSE_VISIT_NO_CHILDREN)
return (0);
- if (tv->tv_err)
- return (tv->tv_err);
+ if (err == ERESTART)
+ pause = B_TRUE; /* handle pausing at a common point */
+ if (err != 0)
+ goto post;
}
- if (BP_GET_LEVEL(tv->tv_bp) > 0) {
- tv->tv_epb = BP_GET_LSIZE(tv->tv_bp) >> SPA_BLKPTRSHIFT;
+ if (BP_GET_LEVEL(bp) > 0) {
+ uint32_t flags = ARC_WAIT;
+ int i;
+ blkptr_t *cbp;
+ int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT;
- tv->tv_err = dsl_read(NULL, tv->tv_td->td_spa, tv->tv_bp,
- tv->tv_pbuf, arc_getbuf_func, &tv->tv_buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
- &tv->tv_flags, tv->tv_zb);
- if (tv->tv_err)
- return (tv->tv_err);
+ err = dsl_read(NULL, td->td_spa, bp, pbuf,
+ arc_getbuf_func, &buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
+ if (err)
+ return (err);
/* recursively visitbp() blocks below this */
- tv->tv_cbp = tv->tv_buf->b_data;
- for (tv->tv_i = 0; tv->tv_i < tv->tv_epb;
- tv->tv_i++, tv->tv_cbp++) {
- SET_BOOKMARK(&tv->tv_czb, tv->tv_zb->zb_objset,
- tv->tv_zb->zb_object, tv->tv_zb->zb_level - 1,
- tv->tv_zb->zb_blkid * tv->tv_epb + tv->tv_i);
- __traverse_visitbp_init(tv + 1, tv->tv_td,
- tv->tv_dnp, tv->tv_buf, tv->tv_cbp,
- &tv->tv_czb, tv->tv_depth + 1);
- tv->tv_err = __traverse_visitbp(tv + 1);
- if (tv->tv_err) {
- if (!tv->tv_hard)
+ cbp = buf->b_data;
+ for (i = 0; i < epb; i++, cbp++) {
+ SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object,
+ zb->zb_level - 1,
+ zb->zb_blkid * epb + i);
+ err = traverse_visitbp(td, dnp, buf, cbp, &czb);
+ if (err) {
+ if (!hard)
break;
- tv->tv_lasterr = tv->tv_err;
+ lasterr = err;
}
}
- } else if (BP_GET_TYPE(tv->tv_bp) == DMU_OT_DNODE) {
- tv->tv_epb = BP_GET_LSIZE(tv->tv_bp) >> DNODE_SHIFT;
-
- tv->tv_err = dsl_read(NULL, tv->tv_td->td_spa, tv->tv_bp,
- tv->tv_pbuf, arc_getbuf_func, &tv->tv_buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
- &tv->tv_flags, tv->tv_zb);
- if (tv->tv_err)
- return (tv->tv_err);
+ } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) {
+ uint32_t flags = ARC_WAIT;
+ int i;
+ int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT;
+
+ err = dsl_read(NULL, td->td_spa, bp, pbuf,
+ arc_getbuf_func, &buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
+ if (err)
+ return (err);
/* recursively visitbp() blocks below this */
- tv->tv_dnp = tv->tv_buf->b_data;
- for (tv->tv_i = 0; tv->tv_i < tv->tv_epb;
- tv->tv_i++, tv->tv_dnp++) {
- tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_dnp,
- tv->tv_buf, tv->tv_zb->zb_objset,
- tv->tv_zb->zb_blkid * tv->tv_epb + tv->tv_i);
- if (tv->tv_err) {
- if (!tv->tv_hard)
+ dnp = buf->b_data;
+ for (i = 0; i < epb; i++, dnp++) {
+ err = traverse_dnode(td, dnp, buf, zb->zb_objset,
+ zb->zb_blkid * epb + i);
+ if (err) {
+ if (!hard)
break;
- tv->tv_lasterr = tv->tv_err;
+ lasterr = err;
}
}
- } else if (BP_GET_TYPE(tv->tv_bp) == DMU_OT_OBJSET) {
-
- tv->tv_err = dsl_read_nolock(NULL, tv->tv_td->td_spa,
- tv->tv_bp, arc_getbuf_func, &tv->tv_buf,
- ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL,
- &tv->tv_flags, tv->tv_zb);
- if (tv->tv_err)
- return (tv->tv_err);
-
- tv->tv_osp = tv->tv_buf->b_data;
- tv->tv_ldnp = &tv->tv_osp->os_meta_dnode;
- tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp, tv->tv_buf,
- tv->tv_zb->zb_objset, DMU_META_DNODE_OBJECT);
- if (tv->tv_err && tv->tv_hard) {
- tv->tv_lasterr = tv->tv_err;
- tv->tv_err = 0;
+ } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) {
+ uint32_t flags = ARC_WAIT;
+ objset_phys_t *osp;
+ dnode_phys_t *dnp;
+
+ err = dsl_read_nolock(NULL, td->td_spa, bp,
+ arc_getbuf_func, &buf,
+ ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
+ if (err)
+ return (err);
+
+ osp = buf->b_data;
+ dnp = &osp->os_meta_dnode;
+ err = traverse_dnode(td, dnp, buf, zb->zb_objset,
+ DMU_META_DNODE_OBJECT);
+ if (err && hard) {
+ lasterr = err;
+ err = 0;
}
- if (tv->tv_err == 0 &&
- arc_buf_size(tv->tv_buf) >= sizeof (objset_phys_t)) {
- tv->tv_ldnp = &tv->tv_osp->os_userused_dnode;
- tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp,
- tv->tv_buf, tv->tv_zb->zb_objset,
+ if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) {
+ dnp = &osp->os_userused_dnode;
+ err = traverse_dnode(td, dnp, buf, zb->zb_objset,
DMU_USERUSED_OBJECT);
}
- if (tv->tv_err && tv->tv_hard) {
- tv->tv_lasterr = tv->tv_err;
- tv->tv_err = 0;
+ if (err && hard) {
+ lasterr = err;
+ err = 0;
}
- if (tv->tv_err == 0 &&
- arc_buf_size(tv->tv_buf) >= sizeof (objset_phys_t)) {
- tv->tv_ldnp = &tv->tv_osp->os_groupused_dnode;
- tv->tv_err = traverse_dnode(tv->tv_td, tv->tv_ldnp,
- tv->tv_buf, tv->tv_zb->zb_objset,
+ if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) {
+ dnp = &osp->os_groupused_dnode;
+ err = traverse_dnode(td, dnp, buf, zb->zb_objset,
DMU_GROUPUSED_OBJECT);
}
}
- if (tv->tv_buf)
- (void) arc_buf_remove_ref(tv->tv_buf, &tv->tv_buf);
+ if (buf)
+ (void) arc_buf_remove_ref(buf, &buf);
- if (tv->tv_err == 0 && tv->tv_lasterr == 0 &&
- (tv->tv_td->td_flags & TRAVERSE_POST)) {
- tv->tv_err = tv->tv_td->td_func(tv->tv_td->td_spa, NULL,
- tv->tv_bp, tv->tv_pbuf, tv->tv_zb, tv->tv_dnp,
- tv->tv_td->td_arg);
+post:
+ if (err == 0 && lasterr == 0 && (td->td_flags & TRAVERSE_POST)) {
+ err = td->td_func(td->td_spa, NULL, bp, pbuf, zb, dnp,
+ td->td_arg);
+ if (err == ERESTART)
+ pause = B_TRUE;
}
- return (tv->tv_err != 0 ? tv->tv_err : tv->tv_lasterr);
-}
-
-/*
- * Due to limited stack space recursive functions are frowned upon in
- * the Linux kernel. However, they often are the most elegant solution
- * to a problem. The following code preserves the recursive function
- * traverse_visitbp() but moves the local variables AND function
- * arguments to the heap to minimize the stack frame size. Enough
- * space is initially allocated on the stack for 16 levels of recursion.
- * This change does ugly-up-the-code but it reduces the worst case
- * usage from roughly 2496 bytes to 576 bytes on x86_64 archs.
- */
-static int
-traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp,
- arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb)
-{
- traverse_visitbp_data_t *tv;
- int error;
-
- tv = kmem_zalloc(sizeof(traverse_visitbp_data_t) *
- TRAVERSE_VISITBP_MAX_DEPTH, KM_SLEEP);
- __traverse_visitbp_init(tv, td, dnp, pbuf, bp, zb, 0);
-
- error = __traverse_visitbp(tv);
-
- kmem_free(tv, sizeof(traverse_visitbp_data_t) *
- TRAVERSE_VISITBP_MAX_DEPTH);
+ if (pause && td->td_resume != NULL) {
+ ASSERT3U(err, ==, ERESTART);
+ ASSERT(!hard);
+ traverse_pause(td, zb);
+ }
- return (error);
+ return (err != 0 ? err : lasterr);
}
static int
* in syncing context).
*/
static int
-traverse_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *rootbp,
- uint64_t txg_start, int flags, blkptr_cb_t func, void *arg)
+traverse_impl(spa_t *spa, dsl_dataset_t *ds, uint64_t objset, blkptr_t *rootbp,
+ uint64_t txg_start, zbookmark_t *resume, int flags,
+ blkptr_cb_t func, void *arg)
{
traverse_data_t *td;
prefetch_data_t *pd;
zbookmark_t *czb;
int err;
- td = kmem_alloc(sizeof(traverse_data_t), KM_SLEEP);
- pd = kmem_zalloc(sizeof(prefetch_data_t), KM_SLEEP);
- czb = kmem_alloc(sizeof(zbookmark_t), KM_SLEEP);
+ ASSERT(ds == NULL || objset == ds->ds_object);
+ ASSERT(!(flags & TRAVERSE_PRE) || !(flags & TRAVERSE_POST));
+
+ td = kmem_alloc(sizeof(traverse_data_t), KM_PUSHPAGE);
+ pd = kmem_zalloc(sizeof(prefetch_data_t), KM_PUSHPAGE);
+ czb = kmem_alloc(sizeof(zbookmark_t), KM_PUSHPAGE);
td->td_spa = spa;
- td->td_objset = ds ? ds->ds_object : 0;
+ td->td_objset = objset;
td->td_rootbp = rootbp;
td->td_min_txg = txg_start;
+ td->td_resume = resume;
td->td_func = func;
td->td_arg = arg;
td->td_pfd = pd;
traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, int flags,
blkptr_cb_t func, void *arg)
{
- return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds,
- &ds->ds_phys->ds_bp, txg_start, flags, func, arg));
+ return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds, ds->ds_object,
+ &ds->ds_phys->ds_bp, txg_start, NULL, flags, func, arg));
+}
+
+int
+traverse_dataset_destroyed(spa_t *spa, blkptr_t *blkptr,
+ uint64_t txg_start, zbookmark_t *resume, int flags,
+ blkptr_cb_t func, void *arg)
+{
+ return (traverse_impl(spa, NULL, ZB_DESTROYED_OBJSET,
+ blkptr, txg_start, resume, flags, func, arg));
}
/*
boolean_t hard = (flags & TRAVERSE_HARD);
/* visit the MOS */
- err = traverse_impl(spa, NULL, spa_get_rootblkptr(spa),
- txg_start, flags, func, arg);
+ err = traverse_impl(spa, NULL, 0, spa_get_rootblkptr(spa),
+ txg_start, NULL, flags, func, arg);
if (err)
return (err);
#if defined(_KERNEL) && defined(HAVE_SPL)
EXPORT_SYMBOL(traverse_dataset);
EXPORT_SYMBOL(traverse_pool);
+
+module_param(zfs_pd_blks_max, int, 0644);
+MODULE_PARM_DESC(zfs_pd_blks_max, "Max number of blocks to prefetch");
#endif
git://git.camperquake.de / zfs.git / blobdiff