--- /dev/null
+/*
+ * 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) 2013, 2014 by Delphix. All rights reserved.
+ */
+
+#include <sys/zfs_context.h>
+#include <sys/spa.h>
+#include <sys/dmu.h>
+#include <sys/dnode.h>
+#include <sys/zio.h>
+#include <sys/range_tree.h>
+
+kmem_cache_t *range_seg_cache;
+
+void
+range_tree_init(void)
+{
+ ASSERT(range_seg_cache == NULL);
+ range_seg_cache = kmem_cache_create("range_seg_cache",
+ sizeof (range_seg_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
+}
+
+void
+range_tree_fini(void)
+{
+ kmem_cache_destroy(range_seg_cache);
+ range_seg_cache = NULL;
+}
+
+void
+range_tree_stat_verify(range_tree_t *rt)
+{
+ range_seg_t *rs;
+ uint64_t hist[RANGE_TREE_HISTOGRAM_SIZE] = { 0 };
+ int i;
+
+ for (rs = avl_first(&rt->rt_root); rs != NULL;
+ rs = AVL_NEXT(&rt->rt_root, rs)) {
+ uint64_t size = rs->rs_end - rs->rs_start;
+ int idx = highbit64(size) - 1;
+
+ hist[idx]++;
+ ASSERT3U(hist[idx], !=, 0);
+ }
+
+ for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
+ if (hist[i] != rt->rt_histogram[i]) {
+ zfs_dbgmsg("i=%d, hist=%p, hist=%llu, rt_hist=%llu",
+ i, hist, hist[i], rt->rt_histogram[i]);
+ }
+ VERIFY3U(hist[i], ==, rt->rt_histogram[i]);
+ }
+}
+
+static void
+range_tree_stat_incr(range_tree_t *rt, range_seg_t *rs)
+{
+ uint64_t size = rs->rs_end - rs->rs_start;
+ int idx = highbit64(size) - 1;
+
+ ASSERT(size != 0);
+ ASSERT3U(idx, <,
+ sizeof (rt->rt_histogram) / sizeof (*rt->rt_histogram));
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ rt->rt_histogram[idx]++;
+ ASSERT3U(rt->rt_histogram[idx], !=, 0);
+}
+
+static void
+range_tree_stat_decr(range_tree_t *rt, range_seg_t *rs)
+{
+ uint64_t size = rs->rs_end - rs->rs_start;
+ int idx = highbit64(size) - 1;
+
+ ASSERT(size != 0);
+ ASSERT3U(idx, <,
+ sizeof (rt->rt_histogram) / sizeof (*rt->rt_histogram));
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ ASSERT3U(rt->rt_histogram[idx], !=, 0);
+ rt->rt_histogram[idx]--;
+}
+
+/*
+ * NOTE: caller is responsible for all locking.
+ */
+static int
+range_tree_seg_compare(const void *x1, const void *x2)
+{
+ const range_seg_t *r1 = x1;
+ const range_seg_t *r2 = x2;
+
+ if (r1->rs_start < r2->rs_start) {
+ if (r1->rs_end > r2->rs_start)
+ return (0);
+ return (-1);
+ }
+ if (r1->rs_start > r2->rs_start) {
+ if (r1->rs_start < r2->rs_end)
+ return (0);
+ return (1);
+ }
+ return (0);
+}
+
+range_tree_t *
+range_tree_create(range_tree_ops_t *ops, void *arg, kmutex_t *lp)
+{
+ range_tree_t *rt;
+
+ rt = kmem_zalloc(sizeof (range_tree_t), KM_SLEEP);
+
+ avl_create(&rt->rt_root, range_tree_seg_compare,
+ sizeof (range_seg_t), offsetof(range_seg_t, rs_node));
+
+ rt->rt_lock = lp;
+ rt->rt_ops = ops;
+ rt->rt_arg = arg;
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_create(rt, rt->rt_arg);
+
+ return (rt);
+}
+
+void
+range_tree_destroy(range_tree_t *rt)
+{
+ VERIFY0(rt->rt_space);
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_destroy(rt, rt->rt_arg);
+
+ avl_destroy(&rt->rt_root);
+ kmem_free(rt, sizeof (*rt));
+}
+
+void
+range_tree_add(void *arg, uint64_t start, uint64_t size)
+{
+ range_tree_t *rt = arg;
+ avl_index_t where;
+ range_seg_t rsearch, *rs_before, *rs_after, *rs;
+ uint64_t end = start + size;
+ boolean_t merge_before, merge_after;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ VERIFY(size != 0);
+
+ rsearch.rs_start = start;
+ rsearch.rs_end = end;
+ rs = avl_find(&rt->rt_root, &rsearch, &where);
+
+ if (rs != NULL && rs->rs_start <= start && rs->rs_end >= end) {
+ zfs_panic_recover("zfs: allocating allocated segment"
+ "(offset=%llu size=%llu)\n",
+ (longlong_t)start, (longlong_t)size);
+ return;
+ }
+
+ /* Make sure we don't overlap with either of our neighbors */
+ VERIFY(rs == NULL);
+
+ rs_before = avl_nearest(&rt->rt_root, where, AVL_BEFORE);
+ rs_after = avl_nearest(&rt->rt_root, where, AVL_AFTER);
+
+ merge_before = (rs_before != NULL && rs_before->rs_end == start);
+ merge_after = (rs_after != NULL && rs_after->rs_start == end);
+
+ if (merge_before && merge_after) {
+ avl_remove(&rt->rt_root, rs_before);
+ if (rt->rt_ops != NULL) {
+ rt->rt_ops->rtop_remove(rt, rs_before, rt->rt_arg);
+ rt->rt_ops->rtop_remove(rt, rs_after, rt->rt_arg);
+ }
+
+ range_tree_stat_decr(rt, rs_before);
+ range_tree_stat_decr(rt, rs_after);
+
+ rs_after->rs_start = rs_before->rs_start;
+ kmem_cache_free(range_seg_cache, rs_before);
+ rs = rs_after;
+ } else if (merge_before) {
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_remove(rt, rs_before, rt->rt_arg);
+
+ range_tree_stat_decr(rt, rs_before);
+
+ rs_before->rs_end = end;
+ rs = rs_before;
+ } else if (merge_after) {
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_remove(rt, rs_after, rt->rt_arg);
+
+ range_tree_stat_decr(rt, rs_after);
+
+ rs_after->rs_start = start;
+ rs = rs_after;
+ } else {
+ rs = kmem_cache_alloc(range_seg_cache, KM_SLEEP);
+ rs->rs_start = start;
+ rs->rs_end = end;
+ avl_insert(&rt->rt_root, rs, where);
+ }
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_add(rt, rs, rt->rt_arg);
+
+ range_tree_stat_incr(rt, rs);
+ rt->rt_space += size;
+}
+
+void
+range_tree_remove(void *arg, uint64_t start, uint64_t size)
+{
+ range_tree_t *rt = arg;
+ avl_index_t where;
+ range_seg_t rsearch, *rs, *newseg;
+ uint64_t end = start + size;
+ boolean_t left_over, right_over;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ VERIFY3U(size, !=, 0);
+ VERIFY3U(size, <=, rt->rt_space);
+
+ rsearch.rs_start = start;
+ rsearch.rs_end = end;
+ rs = avl_find(&rt->rt_root, &rsearch, &where);
+
+ /* Make sure we completely overlap with someone */
+ if (rs == NULL) {
+ zfs_panic_recover("zfs: freeing free segment "
+ "(offset=%llu size=%llu)",
+ (longlong_t)start, (longlong_t)size);
+ return;
+ }
+ VERIFY3U(rs->rs_start, <=, start);
+ VERIFY3U(rs->rs_end, >=, end);
+
+ left_over = (rs->rs_start != start);
+ right_over = (rs->rs_end != end);
+
+ range_tree_stat_decr(rt, rs);
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_remove(rt, rs, rt->rt_arg);
+
+ if (left_over && right_over) {
+ newseg = kmem_cache_alloc(range_seg_cache, KM_SLEEP);
+ newseg->rs_start = end;
+ newseg->rs_end = rs->rs_end;
+ range_tree_stat_incr(rt, newseg);
+
+ rs->rs_end = start;
+
+ avl_insert_here(&rt->rt_root, newseg, rs, AVL_AFTER);
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_add(rt, newseg, rt->rt_arg);
+ } else if (left_over) {
+ rs->rs_end = start;
+ } else if (right_over) {
+ rs->rs_start = end;
+ } else {
+ avl_remove(&rt->rt_root, rs);
+ kmem_cache_free(range_seg_cache, rs);
+ rs = NULL;
+ }
+
+ if (rs != NULL) {
+ range_tree_stat_incr(rt, rs);
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_add(rt, rs, rt->rt_arg);
+ }
+
+ rt->rt_space -= size;
+}
+
+static range_seg_t *
+range_tree_find_impl(range_tree_t *rt, uint64_t start, uint64_t size)
+{
+ avl_index_t where;
+ range_seg_t rsearch;
+ uint64_t end = start + size;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ VERIFY(size != 0);
+
+ rsearch.rs_start = start;
+ rsearch.rs_end = end;
+ return (avl_find(&rt->rt_root, &rsearch, &where));
+}
+
+static range_seg_t *
+range_tree_find(range_tree_t *rt, uint64_t start, uint64_t size)
+{
+ range_seg_t *rs = range_tree_find_impl(rt, start, size);
+ if (rs != NULL && rs->rs_start <= start && rs->rs_end >= start + size)
+ return (rs);
+ return (NULL);
+}
+
+void
+range_tree_verify(range_tree_t *rt, uint64_t off, uint64_t size)
+{
+ range_seg_t *rs;
+
+ mutex_enter(rt->rt_lock);
+ rs = range_tree_find(rt, off, size);
+ if (rs != NULL)
+ panic("freeing free block; rs=%p", (void *)rs);
+ mutex_exit(rt->rt_lock);
+}
+
+boolean_t
+range_tree_contains(range_tree_t *rt, uint64_t start, uint64_t size)
+{
+ return (range_tree_find(rt, start, size) != NULL);
+}
+
+/*
+ * Ensure that this range is not in the tree, regardless of whether
+ * it is currently in the tree.
+ */
+void
+range_tree_clear(range_tree_t *rt, uint64_t start, uint64_t size)
+{
+ range_seg_t *rs;
+
+ while ((rs = range_tree_find_impl(rt, start, size)) != NULL) {
+ uint64_t free_start = MAX(rs->rs_start, start);
+ uint64_t free_end = MIN(rs->rs_end, start + size);
+ range_tree_remove(rt, free_start, free_end - free_start);
+ }
+}
+
+void
+range_tree_swap(range_tree_t **rtsrc, range_tree_t **rtdst)
+{
+ range_tree_t *rt;
+
+ ASSERT(MUTEX_HELD((*rtsrc)->rt_lock));
+ ASSERT0(range_tree_space(*rtdst));
+ ASSERT0(avl_numnodes(&(*rtdst)->rt_root));
+
+ rt = *rtsrc;
+ *rtsrc = *rtdst;
+ *rtdst = rt;
+}
+
+void
+range_tree_vacate(range_tree_t *rt, range_tree_func_t *func, void *arg)
+{
+ range_seg_t *rs;
+ void *cookie = NULL;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+
+ if (rt->rt_ops != NULL)
+ rt->rt_ops->rtop_vacate(rt, rt->rt_arg);
+
+ while ((rs = avl_destroy_nodes(&rt->rt_root, &cookie)) != NULL) {
+ if (func != NULL)
+ func(arg, rs->rs_start, rs->rs_end - rs->rs_start);
+ kmem_cache_free(range_seg_cache, rs);
+ }
+
+ bzero(rt->rt_histogram, sizeof (rt->rt_histogram));
+ rt->rt_space = 0;
+}
+
+void
+range_tree_walk(range_tree_t *rt, range_tree_func_t *func, void *arg)
+{
+ range_seg_t *rs;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+
+ for (rs = avl_first(&rt->rt_root); rs; rs = AVL_NEXT(&rt->rt_root, rs))
+ func(arg, rs->rs_start, rs->rs_end - rs->rs_start);
+}
+
+uint64_t
+range_tree_space(range_tree_t *rt)
+{
+ return (rt->rt_space);
+}
projects / mirror_ubuntu-artful-kernel.git / blobdiff