freebsd-dev/module/zfs/space_map.c
Brian Behlendorf 79c76d5b65 Change KM_PUSHPAGE -> KM_SLEEP
By marking DMU transaction processing contexts with PF_FSTRANS
we can revert the KM_PUSHPAGE -> KM_SLEEP changes.  This brings
us back in line with upstream.  In some cases this means simply
swapping the flags back.  For others fnvlist_alloc() was replaced
by nvlist_alloc(..., KM_PUSHPAGE) and must be reverted back to
fnvlist_alloc() which assumes KM_SLEEP.

The one place KM_PUSHPAGE is kept is when allocating ARC buffers
which allows us to dip in to reserved memory.  This is again the
same as upstream.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-01-16 14:41:26 -08:00

552 lines
14 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) 2012, 2014 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
#include <sys/dmu.h>
#include <sys/dmu_tx.h>
#include <sys/dnode.h>
#include <sys/dsl_pool.h>
#include <sys/zio.h>
#include <sys/space_map.h>
#include <sys/refcount.h>
#include <sys/zfeature.h>
/*
* The data for a given space map can be kept on blocks of any size.
* Larger blocks entail fewer i/o operations, but they also cause the
* DMU to keep more data in-core, and also to waste more i/o bandwidth
* when only a few blocks have changed since the last transaction group.
*/
int space_map_blksz = (1 << 12);
/*
* Load the space map disk into the specified range tree. Segments of maptype
* are added to the range tree, other segment types are removed.
*
* Note: space_map_load() will drop sm_lock across dmu_read() calls.
* The caller must be OK with this.
*/
int
space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype)
{
uint64_t *entry, *entry_map, *entry_map_end;
uint64_t bufsize, size, offset, end, space;
int error = 0;
ASSERT(MUTEX_HELD(sm->sm_lock));
end = space_map_length(sm);
space = space_map_allocated(sm);
VERIFY0(range_tree_space(rt));
if (maptype == SM_FREE) {
range_tree_add(rt, sm->sm_start, sm->sm_size);
space = sm->sm_size - space;
}
bufsize = MAX(sm->sm_blksz, SPA_MINBLOCKSIZE);
entry_map = zio_buf_alloc(bufsize);
mutex_exit(sm->sm_lock);
if (end > bufsize) {
dmu_prefetch(sm->sm_os, space_map_object(sm), bufsize,
end - bufsize);
}
mutex_enter(sm->sm_lock);
for (offset = 0; offset < end; offset += bufsize) {
size = MIN(end - offset, bufsize);
VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0);
VERIFY(size != 0);
ASSERT3U(sm->sm_blksz, !=, 0);
dprintf("object=%llu offset=%llx size=%llx\n",
space_map_object(sm), offset, size);
mutex_exit(sm->sm_lock);
error = dmu_read(sm->sm_os, space_map_object(sm), offset, size,
entry_map, DMU_READ_PREFETCH);
mutex_enter(sm->sm_lock);
if (error != 0)
break;
entry_map_end = entry_map + (size / sizeof (uint64_t));
for (entry = entry_map; entry < entry_map_end; entry++) {
uint64_t e = *entry;
uint64_t offset, size;
if (SM_DEBUG_DECODE(e)) /* Skip debug entries */
continue;
offset = (SM_OFFSET_DECODE(e) << sm->sm_shift) +
sm->sm_start;
size = SM_RUN_DECODE(e) << sm->sm_shift;
VERIFY0(P2PHASE(offset, 1ULL << sm->sm_shift));
VERIFY0(P2PHASE(size, 1ULL << sm->sm_shift));
VERIFY3U(offset, >=, sm->sm_start);
VERIFY3U(offset + size, <=, sm->sm_start + sm->sm_size);
if (SM_TYPE_DECODE(e) == maptype) {
VERIFY3U(range_tree_space(rt) + size, <=,
sm->sm_size);
range_tree_add(rt, offset, size);
} else {
range_tree_remove(rt, offset, size);
}
}
}
if (error == 0)
VERIFY3U(range_tree_space(rt), ==, space);
else
range_tree_vacate(rt, NULL, NULL);
zio_buf_free(entry_map, bufsize);
return (error);
}
void
space_map_histogram_clear(space_map_t *sm)
{
if (sm->sm_dbuf->db_size != sizeof (space_map_phys_t))
return;
bzero(sm->sm_phys->smp_histogram, sizeof (sm->sm_phys->smp_histogram));
}
boolean_t
space_map_histogram_verify(space_map_t *sm, range_tree_t *rt)
{
int i;
/*
* Verify that the in-core range tree does not have any
* ranges smaller than our sm_shift size.
*/
for (i = 0; i < sm->sm_shift; i++) {
if (rt->rt_histogram[i] != 0)
return (B_FALSE);
}
return (B_TRUE);
}
void
space_map_histogram_add(space_map_t *sm, range_tree_t *rt, dmu_tx_t *tx)
{
int idx = 0;
int i;
ASSERT(MUTEX_HELD(rt->rt_lock));
ASSERT(dmu_tx_is_syncing(tx));
VERIFY3U(space_map_object(sm), !=, 0);
if (sm->sm_dbuf->db_size != sizeof (space_map_phys_t))
return;
dmu_buf_will_dirty(sm->sm_dbuf, tx);
ASSERT(space_map_histogram_verify(sm, rt));
/*
* Transfer the content of the range tree histogram to the space
* map histogram. The space map histogram contains 32 buckets ranging
* between 2^sm_shift to 2^(32+sm_shift-1). The range tree,
* however, can represent ranges from 2^0 to 2^63. Since the space
* map only cares about allocatable blocks (minimum of sm_shift) we
* can safely ignore all ranges in the range tree smaller than sm_shift.
*/
for (i = sm->sm_shift; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
/*
* Since the largest histogram bucket in the space map is
* 2^(32+sm_shift-1), we need to normalize the values in
* the range tree for any bucket larger than that size. For
* example given an sm_shift of 9, ranges larger than 2^40
* would get normalized as if they were 1TB ranges. Assume
* the range tree had a count of 5 in the 2^44 (16TB) bucket,
* the calculation below would normalize this to 5 * 2^4 (16).
*/
ASSERT3U(i, >=, idx + sm->sm_shift);
sm->sm_phys->smp_histogram[idx] +=
rt->rt_histogram[i] << (i - idx - sm->sm_shift);
/*
* Increment the space map's index as long as we haven't
* reached the maximum bucket size. Accumulate all ranges
* larger than the max bucket size into the last bucket.
*/
if (idx < SPACE_MAP_HISTOGRAM_SIZE - 1) {
ASSERT3U(idx + sm->sm_shift, ==, i);
idx++;
ASSERT3U(idx, <, SPACE_MAP_HISTOGRAM_SIZE);
}
}
}
uint64_t
space_map_entries(space_map_t *sm, range_tree_t *rt)
{
avl_tree_t *t = &rt->rt_root;
range_seg_t *rs;
uint64_t size, entries;
/*
* All space_maps always have a debug entry so account for it here.
*/
entries = 1;
/*
* Traverse the range tree and calculate the number of space map
* entries that would be required to write out the range tree.
*/
for (rs = avl_first(t); rs != NULL; rs = AVL_NEXT(t, rs)) {
size = (rs->rs_end - rs->rs_start) >> sm->sm_shift;
entries += howmany(size, SM_RUN_MAX);
}
return (entries);
}
/*
* Note: space_map_write() will drop sm_lock across dmu_write() calls.
*/
void
space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype,
dmu_tx_t *tx)
{
objset_t *os = sm->sm_os;
spa_t *spa = dmu_objset_spa(os);
avl_tree_t *t = &rt->rt_root;
range_seg_t *rs;
uint64_t size, total, rt_space, nodes;
uint64_t *entry, *entry_map, *entry_map_end;
uint64_t expected_entries, actual_entries = 1;
ASSERT(MUTEX_HELD(rt->rt_lock));
ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
VERIFY3U(space_map_object(sm), !=, 0);
dmu_buf_will_dirty(sm->sm_dbuf, tx);
/*
* This field is no longer necessary since the in-core space map
* now contains the object number but is maintained for backwards
* compatibility.
*/
sm->sm_phys->smp_object = sm->sm_object;
if (range_tree_space(rt) == 0) {
VERIFY3U(sm->sm_object, ==, sm->sm_phys->smp_object);
return;
}
if (maptype == SM_ALLOC)
sm->sm_phys->smp_alloc += range_tree_space(rt);
else
sm->sm_phys->smp_alloc -= range_tree_space(rt);
expected_entries = space_map_entries(sm, rt);
entry_map = zio_buf_alloc(sm->sm_blksz);
entry_map_end = entry_map + (sm->sm_blksz / sizeof (uint64_t));
entry = entry_map;
*entry++ = SM_DEBUG_ENCODE(1) |
SM_DEBUG_ACTION_ENCODE(maptype) |
SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) |
SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx));
total = 0;
nodes = avl_numnodes(&rt->rt_root);
rt_space = range_tree_space(rt);
for (rs = avl_first(t); rs != NULL; rs = AVL_NEXT(t, rs)) {
uint64_t start;
size = (rs->rs_end - rs->rs_start) >> sm->sm_shift;
start = (rs->rs_start - sm->sm_start) >> sm->sm_shift;
total += size << sm->sm_shift;
while (size != 0) {
uint64_t run_len;
run_len = MIN(size, SM_RUN_MAX);
if (entry == entry_map_end) {
mutex_exit(rt->rt_lock);
dmu_write(os, space_map_object(sm),
sm->sm_phys->smp_objsize, sm->sm_blksz,
entry_map, tx);
mutex_enter(rt->rt_lock);
sm->sm_phys->smp_objsize += sm->sm_blksz;
entry = entry_map;
}
*entry++ = SM_OFFSET_ENCODE(start) |
SM_TYPE_ENCODE(maptype) |
SM_RUN_ENCODE(run_len);
start += run_len;
size -= run_len;
actual_entries++;
}
}
if (entry != entry_map) {
size = (entry - entry_map) * sizeof (uint64_t);
mutex_exit(rt->rt_lock);
dmu_write(os, space_map_object(sm), sm->sm_phys->smp_objsize,
size, entry_map, tx);
mutex_enter(rt->rt_lock);
sm->sm_phys->smp_objsize += size;
}
ASSERT3U(expected_entries, ==, actual_entries);
/*
* Ensure that the space_map's accounting wasn't changed
* while we were in the middle of writing it out.
*/
VERIFY3U(nodes, ==, avl_numnodes(&rt->rt_root));
VERIFY3U(range_tree_space(rt), ==, rt_space);
VERIFY3U(range_tree_space(rt), ==, total);
zio_buf_free(entry_map, sm->sm_blksz);
}
static int
space_map_open_impl(space_map_t *sm)
{
int error;
u_longlong_t blocks;
error = dmu_bonus_hold(sm->sm_os, sm->sm_object, sm, &sm->sm_dbuf);
if (error)
return (error);
dmu_object_size_from_db(sm->sm_dbuf, &sm->sm_blksz, &blocks);
sm->sm_phys = sm->sm_dbuf->db_data;
return (0);
}
int
space_map_open(space_map_t **smp, objset_t *os, uint64_t object,
uint64_t start, uint64_t size, uint8_t shift, kmutex_t *lp)
{
space_map_t *sm;
int error;
ASSERT(*smp == NULL);
ASSERT(os != NULL);
ASSERT(object != 0);
sm = kmem_alloc(sizeof (space_map_t), KM_SLEEP);
sm->sm_start = start;
sm->sm_size = size;
sm->sm_shift = shift;
sm->sm_lock = lp;
sm->sm_os = os;
sm->sm_object = object;
sm->sm_length = 0;
sm->sm_alloc = 0;
sm->sm_blksz = 0;
sm->sm_dbuf = NULL;
sm->sm_phys = NULL;
error = space_map_open_impl(sm);
if (error != 0) {
space_map_close(sm);
return (error);
}
*smp = sm;
return (0);
}
void
space_map_close(space_map_t *sm)
{
if (sm == NULL)
return;
if (sm->sm_dbuf != NULL)
dmu_buf_rele(sm->sm_dbuf, sm);
sm->sm_dbuf = NULL;
sm->sm_phys = NULL;
kmem_free(sm, sizeof (*sm));
}
void
space_map_truncate(space_map_t *sm, dmu_tx_t *tx)
{
objset_t *os = sm->sm_os;
spa_t *spa = dmu_objset_spa(os);
dmu_object_info_t doi;
ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
ASSERT(dmu_tx_is_syncing(tx));
dmu_object_info_from_db(sm->sm_dbuf, &doi);
/*
* If the space map has the wrong bonus size (because
* SPA_FEATURE_SPACEMAP_HISTOGRAM has recently been enabled), or
* the wrong block size (because space_map_blksz has changed),
* free and re-allocate its object with the updated sizes.
*
* Otherwise, just truncate the current object.
*/
if ((spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM) &&
doi.doi_bonus_size != sizeof (space_map_phys_t)) ||
doi.doi_data_block_size != space_map_blksz) {
zfs_dbgmsg("txg %llu, spa %s, reallocating: "
"old bonus %llu, old blocksz %u", dmu_tx_get_txg(tx),
spa_name(spa), doi.doi_bonus_size, doi.doi_data_block_size);
space_map_free(sm, tx);
dmu_buf_rele(sm->sm_dbuf, sm);
sm->sm_object = space_map_alloc(sm->sm_os, tx);
VERIFY0(space_map_open_impl(sm));
} else {
VERIFY0(dmu_free_range(os, space_map_object(sm), 0, -1ULL, tx));
/*
* If the spacemap is reallocated, its histogram
* will be reset. Do the same in the common case so that
* bugs related to the uncommon case do not go unnoticed.
*/
bzero(sm->sm_phys->smp_histogram,
sizeof (sm->sm_phys->smp_histogram));
}
dmu_buf_will_dirty(sm->sm_dbuf, tx);
sm->sm_phys->smp_objsize = 0;
sm->sm_phys->smp_alloc = 0;
}
/*
* Update the in-core space_map allocation and length values.
*/
void
space_map_update(space_map_t *sm)
{
if (sm == NULL)
return;
ASSERT(MUTEX_HELD(sm->sm_lock));
sm->sm_alloc = sm->sm_phys->smp_alloc;
sm->sm_length = sm->sm_phys->smp_objsize;
}
uint64_t
space_map_alloc(objset_t *os, dmu_tx_t *tx)
{
spa_t *spa = dmu_objset_spa(os);
uint64_t object;
int bonuslen;
if (spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
spa_feature_incr(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM, tx);
bonuslen = sizeof (space_map_phys_t);
ASSERT3U(bonuslen, <=, dmu_bonus_max());
} else {
bonuslen = SPACE_MAP_SIZE_V0;
}
object = dmu_object_alloc(os,
DMU_OT_SPACE_MAP, space_map_blksz,
DMU_OT_SPACE_MAP_HEADER, bonuslen, tx);
return (object);
}
void
space_map_free(space_map_t *sm, dmu_tx_t *tx)
{
spa_t *spa;
if (sm == NULL)
return;
spa = dmu_objset_spa(sm->sm_os);
if (spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
dmu_object_info_t doi;
dmu_object_info_from_db(sm->sm_dbuf, &doi);
if (doi.doi_bonus_size != SPACE_MAP_SIZE_V0) {
VERIFY(spa_feature_is_active(spa,
SPA_FEATURE_SPACEMAP_HISTOGRAM));
spa_feature_decr(spa,
SPA_FEATURE_SPACEMAP_HISTOGRAM, tx);
}
}
VERIFY3U(dmu_object_free(sm->sm_os, space_map_object(sm), tx), ==, 0);
sm->sm_object = 0;
}
uint64_t
space_map_object(space_map_t *sm)
{
return (sm != NULL ? sm->sm_object : 0);
}
/*
* Returns the already synced, on-disk allocated space.
*/
uint64_t
space_map_allocated(space_map_t *sm)
{
return (sm != NULL ? sm->sm_alloc : 0);
}
/*
* Returns the already synced, on-disk length;
*/
uint64_t
space_map_length(space_map_t *sm)
{
return (sm != NULL ? sm->sm_length : 0);
}
/*
* Returns the allocated space that is currently syncing.
*/
int64_t
space_map_alloc_delta(space_map_t *sm)
{
if (sm == NULL)
return (0);
ASSERT(sm->sm_dbuf != NULL);
return (sm->sm_phys->smp_alloc - space_map_allocated(sm));
}