diff options
Diffstat (limited to 'kernel/fs/btrfs/delayed-ref.c')
| -rw-r--r-- | kernel/fs/btrfs/delayed-ref.c | 962 |
1 files changed, 962 insertions, 0 deletions
diff --git a/kernel/fs/btrfs/delayed-ref.c b/kernel/fs/btrfs/delayed-ref.c new file mode 100644 index 000000000..8f8ed7d20 --- /dev/null +++ b/kernel/fs/btrfs/delayed-ref.c @@ -0,0 +1,962 @@ +/* + * Copyright (C) 2009 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/sort.h> +#include "ctree.h" +#include "delayed-ref.h" +#include "transaction.h" + +struct kmem_cache *btrfs_delayed_ref_head_cachep; +struct kmem_cache *btrfs_delayed_tree_ref_cachep; +struct kmem_cache *btrfs_delayed_data_ref_cachep; +struct kmem_cache *btrfs_delayed_extent_op_cachep; +/* + * delayed back reference update tracking. For subvolume trees + * we queue up extent allocations and backref maintenance for + * delayed processing. This avoids deep call chains where we + * add extents in the middle of btrfs_search_slot, and it allows + * us to buffer up frequently modified backrefs in an rb tree instead + * of hammering updates on the extent allocation tree. + */ + +/* + * compare two delayed tree backrefs with same bytenr and type + */ +static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, + struct btrfs_delayed_tree_ref *ref1, int type) +{ + if (type == BTRFS_TREE_BLOCK_REF_KEY) { + if (ref1->root < ref2->root) + return -1; + if (ref1->root > ref2->root) + return 1; + } else { + if (ref1->parent < ref2->parent) + return -1; + if (ref1->parent > ref2->parent) + return 1; + } + return 0; +} + +/* + * compare two delayed data backrefs with same bytenr and type + */ +static int comp_data_refs(struct btrfs_delayed_data_ref *ref2, + struct btrfs_delayed_data_ref *ref1) +{ + if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) { + if (ref1->root < ref2->root) + return -1; + if (ref1->root > ref2->root) + return 1; + if (ref1->objectid < ref2->objectid) + return -1; + if (ref1->objectid > ref2->objectid) + return 1; + if (ref1->offset < ref2->offset) + return -1; + if (ref1->offset > ref2->offset) + return 1; + } else { + if (ref1->parent < ref2->parent) + return -1; + if (ref1->parent > ref2->parent) + return 1; + } + return 0; +} + +/* + * entries in the rb tree are ordered by the byte number of the extent, + * type of the delayed backrefs and content of delayed backrefs. + */ +static int comp_entry(struct btrfs_delayed_ref_node *ref2, + struct btrfs_delayed_ref_node *ref1, + bool compare_seq) +{ + if (ref1->bytenr < ref2->bytenr) + return -1; + if (ref1->bytenr > ref2->bytenr) + return 1; + if (ref1->is_head && ref2->is_head) + return 0; + if (ref2->is_head) + return -1; + if (ref1->is_head) + return 1; + if (ref1->type < ref2->type) + return -1; + if (ref1->type > ref2->type) + return 1; + if (ref1->no_quota > ref2->no_quota) + return 1; + if (ref1->no_quota < ref2->no_quota) + return -1; + /* merging of sequenced refs is not allowed */ + if (compare_seq) { + if (ref1->seq < ref2->seq) + return -1; + if (ref1->seq > ref2->seq) + return 1; + } + if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY || + ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) { + return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2), + btrfs_delayed_node_to_tree_ref(ref1), + ref1->type); + } else if (ref1->type == BTRFS_EXTENT_DATA_REF_KEY || + ref1->type == BTRFS_SHARED_DATA_REF_KEY) { + return comp_data_refs(btrfs_delayed_node_to_data_ref(ref2), + btrfs_delayed_node_to_data_ref(ref1)); + } + BUG(); + return 0; +} + +/* + * insert a new ref into the rbtree. This returns any existing refs + * for the same (bytenr,parent) tuple, or NULL if the new node was properly + * inserted. + */ +static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root, + struct rb_node *node) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent_node = NULL; + struct btrfs_delayed_ref_node *entry; + struct btrfs_delayed_ref_node *ins; + int cmp; + + ins = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); + while (*p) { + parent_node = *p; + entry = rb_entry(parent_node, struct btrfs_delayed_ref_node, + rb_node); + + cmp = comp_entry(entry, ins, 1); + if (cmp < 0) + p = &(*p)->rb_left; + else if (cmp > 0) + p = &(*p)->rb_right; + else + return entry; + } + + rb_link_node(node, parent_node, p); + rb_insert_color(node, root); + return NULL; +} + +/* insert a new ref to head ref rbtree */ +static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root, + struct rb_node *node) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent_node = NULL; + struct btrfs_delayed_ref_head *entry; + struct btrfs_delayed_ref_head *ins; + u64 bytenr; + + ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node); + bytenr = ins->node.bytenr; + while (*p) { + parent_node = *p; + entry = rb_entry(parent_node, struct btrfs_delayed_ref_head, + href_node); + + if (bytenr < entry->node.bytenr) + p = &(*p)->rb_left; + else if (bytenr > entry->node.bytenr) + p = &(*p)->rb_right; + else + return entry; + } + + rb_link_node(node, parent_node, p); + rb_insert_color(node, root); + return NULL; +} + +/* + * find an head entry based on bytenr. This returns the delayed ref + * head if it was able to find one, or NULL if nothing was in that spot. + * If return_bigger is given, the next bigger entry is returned if no exact + * match is found. + */ +static struct btrfs_delayed_ref_head * +find_ref_head(struct rb_root *root, u64 bytenr, + int return_bigger) +{ + struct rb_node *n; + struct btrfs_delayed_ref_head *entry; + + n = root->rb_node; + entry = NULL; + while (n) { + entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node); + + if (bytenr < entry->node.bytenr) + n = n->rb_left; + else if (bytenr > entry->node.bytenr) + n = n->rb_right; + else + return entry; + } + if (entry && return_bigger) { + if (bytenr > entry->node.bytenr) { + n = rb_next(&entry->href_node); + if (!n) + n = rb_first(root); + entry = rb_entry(n, struct btrfs_delayed_ref_head, + href_node); + return entry; + } + return entry; + } + return NULL; +} + +int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_head *head) +{ + struct btrfs_delayed_ref_root *delayed_refs; + + delayed_refs = &trans->transaction->delayed_refs; + assert_spin_locked(&delayed_refs->lock); + if (mutex_trylock(&head->mutex)) + return 0; + + atomic_inc(&head->node.refs); + spin_unlock(&delayed_refs->lock); + + mutex_lock(&head->mutex); + spin_lock(&delayed_refs->lock); + if (!head->node.in_tree) { + mutex_unlock(&head->mutex); + btrfs_put_delayed_ref(&head->node); + return -EAGAIN; + } + btrfs_put_delayed_ref(&head->node); + return 0; +} + +static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, + struct btrfs_delayed_ref_node *ref) +{ + if (btrfs_delayed_ref_is_head(ref)) { + head = btrfs_delayed_node_to_head(ref); + rb_erase(&head->href_node, &delayed_refs->href_root); + } else { + assert_spin_locked(&head->lock); + rb_erase(&ref->rb_node, &head->ref_root); + } + ref->in_tree = 0; + btrfs_put_delayed_ref(ref); + atomic_dec(&delayed_refs->num_entries); + if (trans->delayed_ref_updates) + trans->delayed_ref_updates--; +} + +static int merge_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, + struct btrfs_delayed_ref_node *ref, u64 seq) +{ + struct rb_node *node; + int mod = 0; + int done = 0; + + node = rb_next(&ref->rb_node); + while (!done && node) { + struct btrfs_delayed_ref_node *next; + + next = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); + node = rb_next(node); + if (seq && next->seq >= seq) + break; + if (comp_entry(ref, next, 0)) + continue; + + if (ref->action == next->action) { + mod = next->ref_mod; + } else { + if (ref->ref_mod < next->ref_mod) { + struct btrfs_delayed_ref_node *tmp; + + tmp = ref; + ref = next; + next = tmp; + done = 1; + } + mod = -next->ref_mod; + } + + drop_delayed_ref(trans, delayed_refs, head, next); + ref->ref_mod += mod; + if (ref->ref_mod == 0) { + drop_delayed_ref(trans, delayed_refs, head, ref); + done = 1; + } else { + /* + * You can't have multiples of the same ref on a tree + * block. + */ + WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || + ref->type == BTRFS_SHARED_BLOCK_REF_KEY); + } + } + return done; +} + +void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head) +{ + struct rb_node *node; + u64 seq = 0; + + assert_spin_locked(&head->lock); + /* + * We don't have too much refs to merge in the case of delayed data + * refs. + */ + if (head->is_data) + return; + + spin_lock(&fs_info->tree_mod_seq_lock); + if (!list_empty(&fs_info->tree_mod_seq_list)) { + struct seq_list *elem; + + elem = list_first_entry(&fs_info->tree_mod_seq_list, + struct seq_list, list); + seq = elem->seq; + } + spin_unlock(&fs_info->tree_mod_seq_lock); + + node = rb_first(&head->ref_root); + while (node) { + struct btrfs_delayed_ref_node *ref; + + ref = rb_entry(node, struct btrfs_delayed_ref_node, + rb_node); + /* We can't merge refs that are outside of our seq count */ + if (seq && ref->seq >= seq) + break; + if (merge_ref(trans, delayed_refs, head, ref, seq)) + node = rb_first(&head->ref_root); + else + node = rb_next(&ref->rb_node); + } +} + +int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, + u64 seq) +{ + struct seq_list *elem; + int ret = 0; + + spin_lock(&fs_info->tree_mod_seq_lock); + if (!list_empty(&fs_info->tree_mod_seq_list)) { + elem = list_first_entry(&fs_info->tree_mod_seq_list, + struct seq_list, list); + if (seq >= elem->seq) { + pr_debug("holding back delayed_ref %#x.%x, lowest is %#x.%x (%p)\n", + (u32)(seq >> 32), (u32)seq, + (u32)(elem->seq >> 32), (u32)elem->seq, + delayed_refs); + ret = 1; + } + } + + spin_unlock(&fs_info->tree_mod_seq_lock); + return ret; +} + +struct btrfs_delayed_ref_head * +btrfs_select_ref_head(struct btrfs_trans_handle *trans) +{ + struct btrfs_delayed_ref_root *delayed_refs; + struct btrfs_delayed_ref_head *head; + u64 start; + bool loop = false; + + delayed_refs = &trans->transaction->delayed_refs; + +again: + start = delayed_refs->run_delayed_start; + head = find_ref_head(&delayed_refs->href_root, start, 1); + if (!head && !loop) { + delayed_refs->run_delayed_start = 0; + start = 0; + loop = true; + head = find_ref_head(&delayed_refs->href_root, start, 1); + if (!head) + return NULL; + } else if (!head && loop) { + return NULL; + } + + while (head->processing) { + struct rb_node *node; + + node = rb_next(&head->href_node); + if (!node) { + if (loop) + return NULL; + delayed_refs->run_delayed_start = 0; + start = 0; + loop = true; + goto again; + } + head = rb_entry(node, struct btrfs_delayed_ref_head, + href_node); + } + + head->processing = 1; + WARN_ON(delayed_refs->num_heads_ready == 0); + delayed_refs->num_heads_ready--; + delayed_refs->run_delayed_start = head->node.bytenr + + head->node.num_bytes; + return head; +} + +/* + * helper function to update an extent delayed ref in the + * rbtree. existing and update must both have the same + * bytenr and parent + * + * This may free existing if the update cancels out whatever + * operation it was doing. + */ +static noinline void +update_existing_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, + struct btrfs_delayed_ref_node *existing, + struct btrfs_delayed_ref_node *update) +{ + if (update->action != existing->action) { + /* + * this is effectively undoing either an add or a + * drop. We decrement the ref_mod, and if it goes + * down to zero we just delete the entry without + * every changing the extent allocation tree. + */ + existing->ref_mod--; + if (existing->ref_mod == 0) + drop_delayed_ref(trans, delayed_refs, head, existing); + else + WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || + existing->type == BTRFS_SHARED_BLOCK_REF_KEY); + } else { + WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || + existing->type == BTRFS_SHARED_BLOCK_REF_KEY); + /* + * the action on the existing ref matches + * the action on the ref we're trying to add. + * Bump the ref_mod by one so the backref that + * is eventually added/removed has the correct + * reference count + */ + existing->ref_mod += update->ref_mod; + } +} + +/* + * helper function to update the accounting in the head ref + * existing and update must have the same bytenr + */ +static noinline void +update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_node *existing, + struct btrfs_delayed_ref_node *update) +{ + struct btrfs_delayed_ref_head *existing_ref; + struct btrfs_delayed_ref_head *ref; + int old_ref_mod; + + existing_ref = btrfs_delayed_node_to_head(existing); + ref = btrfs_delayed_node_to_head(update); + BUG_ON(existing_ref->is_data != ref->is_data); + + spin_lock(&existing_ref->lock); + if (ref->must_insert_reserved) { + /* if the extent was freed and then + * reallocated before the delayed ref + * entries were processed, we can end up + * with an existing head ref without + * the must_insert_reserved flag set. + * Set it again here + */ + existing_ref->must_insert_reserved = ref->must_insert_reserved; + + /* + * update the num_bytes so we make sure the accounting + * is done correctly + */ + existing->num_bytes = update->num_bytes; + + } + + if (ref->extent_op) { + if (!existing_ref->extent_op) { + existing_ref->extent_op = ref->extent_op; + } else { + if (ref->extent_op->update_key) { + memcpy(&existing_ref->extent_op->key, + &ref->extent_op->key, + sizeof(ref->extent_op->key)); + existing_ref->extent_op->update_key = 1; + } + if (ref->extent_op->update_flags) { + existing_ref->extent_op->flags_to_set |= + ref->extent_op->flags_to_set; + existing_ref->extent_op->update_flags = 1; + } + btrfs_free_delayed_extent_op(ref->extent_op); + } + } + /* + * update the reference mod on the head to reflect this new operation, + * only need the lock for this case cause we could be processing it + * currently, for refs we just added we know we're a-ok. + */ + old_ref_mod = existing_ref->total_ref_mod; + existing->ref_mod += update->ref_mod; + existing_ref->total_ref_mod += update->ref_mod; + + /* + * If we are going to from a positive ref mod to a negative or vice + * versa we need to make sure to adjust pending_csums accordingly. + */ + if (existing_ref->is_data) { + if (existing_ref->total_ref_mod >= 0 && old_ref_mod < 0) + delayed_refs->pending_csums -= existing->num_bytes; + if (existing_ref->total_ref_mod < 0 && old_ref_mod >= 0) + delayed_refs->pending_csums += existing->num_bytes; + } + spin_unlock(&existing_ref->lock); +} + +/* + * helper function to actually insert a head node into the rbtree. + * this does all the dirty work in terms of maintaining the correct + * overall modification count. + */ +static noinline struct btrfs_delayed_ref_head * +add_delayed_ref_head(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, int action, int is_data) +{ + struct btrfs_delayed_ref_head *existing; + struct btrfs_delayed_ref_head *head_ref = NULL; + struct btrfs_delayed_ref_root *delayed_refs; + int count_mod = 1; + int must_insert_reserved = 0; + + /* + * the head node stores the sum of all the mods, so dropping a ref + * should drop the sum in the head node by one. + */ + if (action == BTRFS_UPDATE_DELAYED_HEAD) + count_mod = 0; + else if (action == BTRFS_DROP_DELAYED_REF) + count_mod = -1; + + /* + * BTRFS_ADD_DELAYED_EXTENT means that we need to update + * the reserved accounting when the extent is finally added, or + * if a later modification deletes the delayed ref without ever + * inserting the extent into the extent allocation tree. + * ref->must_insert_reserved is the flag used to record + * that accounting mods are required. + * + * Once we record must_insert_reserved, switch the action to + * BTRFS_ADD_DELAYED_REF because other special casing is not required. + */ + if (action == BTRFS_ADD_DELAYED_EXTENT) + must_insert_reserved = 1; + else + must_insert_reserved = 0; + + delayed_refs = &trans->transaction->delayed_refs; + + /* first set the basic ref node struct up */ + atomic_set(&ref->refs, 1); + ref->bytenr = bytenr; + ref->num_bytes = num_bytes; + ref->ref_mod = count_mod; + ref->type = 0; + ref->action = 0; + ref->is_head = 1; + ref->in_tree = 1; + ref->seq = 0; + + head_ref = btrfs_delayed_node_to_head(ref); + head_ref->must_insert_reserved = must_insert_reserved; + head_ref->is_data = is_data; + head_ref->ref_root = RB_ROOT; + head_ref->processing = 0; + head_ref->total_ref_mod = count_mod; + + spin_lock_init(&head_ref->lock); + mutex_init(&head_ref->mutex); + + trace_add_delayed_ref_head(ref, head_ref, action); + + existing = htree_insert(&delayed_refs->href_root, + &head_ref->href_node); + if (existing) { + update_existing_head_ref(delayed_refs, &existing->node, ref); + /* + * we've updated the existing ref, free the newly + * allocated ref + */ + kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref); + head_ref = existing; + } else { + if (is_data && count_mod < 0) + delayed_refs->pending_csums += num_bytes; + delayed_refs->num_heads++; + delayed_refs->num_heads_ready++; + atomic_inc(&delayed_refs->num_entries); + trans->delayed_ref_updates++; + } + return head_ref; +} + +/* + * helper to insert a delayed tree ref into the rbtree. + */ +static noinline void +add_delayed_tree_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_head *head_ref, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, u64 parent, u64 ref_root, int level, + int action, int no_quota) +{ + struct btrfs_delayed_ref_node *existing; + struct btrfs_delayed_tree_ref *full_ref; + struct btrfs_delayed_ref_root *delayed_refs; + u64 seq = 0; + + if (action == BTRFS_ADD_DELAYED_EXTENT) + action = BTRFS_ADD_DELAYED_REF; + + if (is_fstree(ref_root)) + seq = atomic64_read(&fs_info->tree_mod_seq); + delayed_refs = &trans->transaction->delayed_refs; + + /* first set the basic ref node struct up */ + atomic_set(&ref->refs, 1); + ref->bytenr = bytenr; + ref->num_bytes = num_bytes; + ref->ref_mod = 1; + ref->action = action; + ref->is_head = 0; + ref->in_tree = 1; + ref->no_quota = no_quota; + ref->seq = seq; + + full_ref = btrfs_delayed_node_to_tree_ref(ref); + full_ref->parent = parent; + full_ref->root = ref_root; + if (parent) + ref->type = BTRFS_SHARED_BLOCK_REF_KEY; + else + ref->type = BTRFS_TREE_BLOCK_REF_KEY; + full_ref->level = level; + + trace_add_delayed_tree_ref(ref, full_ref, action); + + spin_lock(&head_ref->lock); + existing = tree_insert(&head_ref->ref_root, &ref->rb_node); + if (existing) { + update_existing_ref(trans, delayed_refs, head_ref, existing, + ref); + /* + * we've updated the existing ref, free the newly + * allocated ref + */ + kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref); + } else { + atomic_inc(&delayed_refs->num_entries); + trans->delayed_ref_updates++; + } + spin_unlock(&head_ref->lock); +} + +/* + * helper to insert a delayed data ref into the rbtree. + */ +static noinline void +add_delayed_data_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_head *head_ref, + struct btrfs_delayed_ref_node *ref, u64 bytenr, + u64 num_bytes, u64 parent, u64 ref_root, u64 owner, + u64 offset, int action, int no_quota) +{ + struct btrfs_delayed_ref_node *existing; + struct btrfs_delayed_data_ref *full_ref; + struct btrfs_delayed_ref_root *delayed_refs; + u64 seq = 0; + + if (action == BTRFS_ADD_DELAYED_EXTENT) + action = BTRFS_ADD_DELAYED_REF; + + delayed_refs = &trans->transaction->delayed_refs; + + if (is_fstree(ref_root)) + seq = atomic64_read(&fs_info->tree_mod_seq); + + /* first set the basic ref node struct up */ + atomic_set(&ref->refs, 1); + ref->bytenr = bytenr; + ref->num_bytes = num_bytes; + ref->ref_mod = 1; + ref->action = action; + ref->is_head = 0; + ref->in_tree = 1; + ref->no_quota = no_quota; + ref->seq = seq; + + full_ref = btrfs_delayed_node_to_data_ref(ref); + full_ref->parent = parent; + full_ref->root = ref_root; + if (parent) + ref->type = BTRFS_SHARED_DATA_REF_KEY; + else + ref->type = BTRFS_EXTENT_DATA_REF_KEY; + + full_ref->objectid = owner; + full_ref->offset = offset; + + trace_add_delayed_data_ref(ref, full_ref, action); + + spin_lock(&head_ref->lock); + existing = tree_insert(&head_ref->ref_root, &ref->rb_node); + if (existing) { + update_existing_ref(trans, delayed_refs, head_ref, existing, + ref); + /* + * we've updated the existing ref, free the newly + * allocated ref + */ + kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref); + } else { + atomic_inc(&delayed_refs->num_entries); + trans->delayed_ref_updates++; + } + spin_unlock(&head_ref->lock); +} + +/* + * add a delayed tree ref. This does all of the accounting required + * to make sure the delayed ref is eventually processed before this + * transaction commits. + */ +int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + u64 bytenr, u64 num_bytes, u64 parent, + u64 ref_root, int level, int action, + struct btrfs_delayed_extent_op *extent_op, + int no_quota) +{ + struct btrfs_delayed_tree_ref *ref; + struct btrfs_delayed_ref_head *head_ref; + struct btrfs_delayed_ref_root *delayed_refs; + + if (!is_fstree(ref_root) || !fs_info->quota_enabled) + no_quota = 0; + + BUG_ON(extent_op && extent_op->is_data); + ref = kmem_cache_alloc(btrfs_delayed_tree_ref_cachep, GFP_NOFS); + if (!ref) + return -ENOMEM; + + head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); + if (!head_ref) { + kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref); + return -ENOMEM; + } + + head_ref->extent_op = extent_op; + + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + + /* + * insert both the head node and the new ref without dropping + * the spin lock + */ + head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, + bytenr, num_bytes, action, 0); + + add_delayed_tree_ref(fs_info, trans, head_ref, &ref->node, bytenr, + num_bytes, parent, ref_root, level, action, + no_quota); + spin_unlock(&delayed_refs->lock); + + return 0; +} + +/* + * add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref. + */ +int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + u64 bytenr, u64 num_bytes, + u64 parent, u64 ref_root, + u64 owner, u64 offset, int action, + struct btrfs_delayed_extent_op *extent_op, + int no_quota) +{ + struct btrfs_delayed_data_ref *ref; + struct btrfs_delayed_ref_head *head_ref; + struct btrfs_delayed_ref_root *delayed_refs; + + if (!is_fstree(ref_root) || !fs_info->quota_enabled) + no_quota = 0; + + BUG_ON(extent_op && !extent_op->is_data); + ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS); + if (!ref) + return -ENOMEM; + + head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); + if (!head_ref) { + kmem_cache_free(btrfs_delayed_data_ref_cachep, ref); + return -ENOMEM; + } + + head_ref->extent_op = extent_op; + + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + + /* + * insert both the head node and the new ref without dropping + * the spin lock + */ + head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, + bytenr, num_bytes, action, 1); + + add_delayed_data_ref(fs_info, trans, head_ref, &ref->node, bytenr, + num_bytes, parent, ref_root, owner, offset, + action, no_quota); + spin_unlock(&delayed_refs->lock); + + return 0; +} + +int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info, + struct btrfs_trans_handle *trans, + u64 bytenr, u64 num_bytes, + struct btrfs_delayed_extent_op *extent_op) +{ + struct btrfs_delayed_ref_head *head_ref; + struct btrfs_delayed_ref_root *delayed_refs; + + head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); + if (!head_ref) + return -ENOMEM; + + head_ref->extent_op = extent_op; + + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + + add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, + num_bytes, BTRFS_UPDATE_DELAYED_HEAD, + extent_op->is_data); + + spin_unlock(&delayed_refs->lock); + return 0; +} + +/* + * this does a simple search for the head node for a given extent. + * It must be called with the delayed ref spinlock held, and it returns + * the head node if any where found, or NULL if not. + */ +struct btrfs_delayed_ref_head * +btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr) +{ + struct btrfs_delayed_ref_root *delayed_refs; + + delayed_refs = &trans->transaction->delayed_refs; + return find_ref_head(&delayed_refs->href_root, bytenr, 0); +} + +void btrfs_delayed_ref_exit(void) +{ + if (btrfs_delayed_ref_head_cachep) + kmem_cache_destroy(btrfs_delayed_ref_head_cachep); + if (btrfs_delayed_tree_ref_cachep) + kmem_cache_destroy(btrfs_delayed_tree_ref_cachep); + if (btrfs_delayed_data_ref_cachep) + kmem_cache_destroy(btrfs_delayed_data_ref_cachep); + if (btrfs_delayed_extent_op_cachep) + kmem_cache_destroy(btrfs_delayed_extent_op_cachep); +} + +int btrfs_delayed_ref_init(void) +{ + btrfs_delayed_ref_head_cachep = kmem_cache_create( + "btrfs_delayed_ref_head", + sizeof(struct btrfs_delayed_ref_head), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); + if (!btrfs_delayed_ref_head_cachep) + goto fail; + + btrfs_delayed_tree_ref_cachep = kmem_cache_create( + "btrfs_delayed_tree_ref", + sizeof(struct btrfs_delayed_tree_ref), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); + if (!btrfs_delayed_tree_ref_cachep) + goto fail; + + btrfs_delayed_data_ref_cachep = kmem_cache_create( + "btrfs_delayed_data_ref", + sizeof(struct btrfs_delayed_data_ref), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); + if (!btrfs_delayed_data_ref_cachep) + goto fail; + + btrfs_delayed_extent_op_cachep = kmem_cache_create( + "btrfs_delayed_extent_op", + sizeof(struct btrfs_delayed_extent_op), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); + if (!btrfs_delayed_extent_op_cachep) + goto fail; + + return 0; +fail: + btrfs_delayed_ref_exit(); + return -ENOMEM; +} |