![Qu Wenruo](/assets/img/avatar_default.png)
[BUG]
Btrfs/139 will fail with a high probability if the testing machine (VM)
has only 2G RAM.
Resulting the final write success while it should fail due to EDQUOT,
and the fs will have quota exceeding the limit by 16K.
The simplified reproducer will be: (needs a 2G ram VM)
$ mkfs.btrfs -f $dev
$ mount $dev $mnt
$ btrfs subv create $mnt/subv
$ btrfs quota enable $mnt
$ btrfs quota rescan -w $mnt
$ btrfs qgroup limit -e 1G $mnt/subv
$ for i in $(seq -w 1 8); do
xfs_io -f -c "pwrite 0 128M" $mnt/subv/file_$i > /dev/null
echo "file $i written" > /dev/kmsg
done
$ sync
$ btrfs qgroup show -pcre --raw $mnt
The last pwrite will not trigger EDQUOT and final 'qgroup show' will
show something like:
qgroupid rfer excl max_rfer max_excl parent child
-------- ---- ---- -------- -------- ------ -----
0/5 16384 16384 none none --- ---
0/256 1073758208 1073758208 none 1073741824 --- ---
And 1073758208 is larger than
> 1073741824.
[CAUSE]
It's a bug in btrfs qgroup data reserved space management.
For quota limit, we must ensure that:
reserved (data + metadata) + rfer/excl <= limit
Since rfer/excl is only updated at transaction commmit time, reserved
space needs to be taken special care.
One important part of reserved space is data, and for a new data extent
written to disk, we still need to take the reserved space until
rfer/excl numbers get updated.
Originally when an ordered extent finishes, we migrate the reserved
qgroup data space from extent_io tree to delayed ref head of the data
extent, expecting delayed ref will only be cleaned up at commit
transaction time.
However for small RAM machine, due to memory pressure dirty pages can be
flushed back to disk without committing a transaction.
The related events will be something like:
file 1 written
btrfs_finish_ordered_io: ino=258 ordered offset=0 len=54947840
btrfs_finish_ordered_io: ino=258 ordered offset=54947840 len=5636096
btrfs_finish_ordered_io: ino=258 ordered offset=61153280 len=57344
btrfs_finish_ordered_io: ino=258 ordered offset=61210624 len=8192
btrfs_finish_ordered_io: ino=258 ordered offset=60583936 len=569344
cleanup_ref_head: num_bytes=54947840
cleanup_ref_head: num_bytes=5636096
cleanup_ref_head: num_bytes=569344
cleanup_ref_head: num_bytes=57344
cleanup_ref_head: num_bytes=8192
^^^^^^^^^^^^^^^^ This will free qgroup data reserved space
file 2 written
...
file 8 written
cleanup_ref_head: num_bytes=8192
...
btrfs_commit_transaction <<< the only transaction committed during
the test
When file 2 is written, we have already freed 128M reserved qgroup data
space for ino 258. Thus later write won't trigger EDQUOT.
This allows us to write more data beyond qgroup limit.
In my 2G ram VM, it could reach about 1.2G before hitting EDQUOT.
[FIX]
By moving reserved qgroup data space from btrfs_delayed_ref_head to
btrfs_qgroup_extent_record, we can ensure that reserved qgroup data
space won't be freed half way before commit transaction, thus fix the
problem.
Fixes: f64d5ca868
("btrfs: delayed_ref: Add new function to record reserved space into delayed ref")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
995 lines
27 KiB
C
995 lines
27 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2009 Oracle. All rights reserved.
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*/
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/sort.h>
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#include "ctree.h"
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#include "delayed-ref.h"
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#include "transaction.h"
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#include "qgroup.h"
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struct kmem_cache *btrfs_delayed_ref_head_cachep;
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struct kmem_cache *btrfs_delayed_tree_ref_cachep;
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struct kmem_cache *btrfs_delayed_data_ref_cachep;
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struct kmem_cache *btrfs_delayed_extent_op_cachep;
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/*
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* delayed back reference update tracking. For subvolume trees
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* we queue up extent allocations and backref maintenance for
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* delayed processing. This avoids deep call chains where we
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* add extents in the middle of btrfs_search_slot, and it allows
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* us to buffer up frequently modified backrefs in an rb tree instead
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* of hammering updates on the extent allocation tree.
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*/
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/*
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* compare two delayed tree backrefs with same bytenr and type
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*/
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static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref1,
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struct btrfs_delayed_tree_ref *ref2)
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{
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if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) {
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if (ref1->root < ref2->root)
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return -1;
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if (ref1->root > ref2->root)
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return 1;
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} else {
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if (ref1->parent < ref2->parent)
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return -1;
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if (ref1->parent > ref2->parent)
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return 1;
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}
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return 0;
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}
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/*
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* compare two delayed data backrefs with same bytenr and type
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*/
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static int comp_data_refs(struct btrfs_delayed_data_ref *ref1,
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struct btrfs_delayed_data_ref *ref2)
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{
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if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) {
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if (ref1->root < ref2->root)
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return -1;
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if (ref1->root > ref2->root)
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return 1;
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if (ref1->objectid < ref2->objectid)
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return -1;
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if (ref1->objectid > ref2->objectid)
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return 1;
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if (ref1->offset < ref2->offset)
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return -1;
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if (ref1->offset > ref2->offset)
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return 1;
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} else {
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if (ref1->parent < ref2->parent)
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return -1;
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if (ref1->parent > ref2->parent)
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return 1;
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}
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return 0;
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}
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static int comp_refs(struct btrfs_delayed_ref_node *ref1,
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struct btrfs_delayed_ref_node *ref2,
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bool check_seq)
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{
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int ret = 0;
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if (ref1->type < ref2->type)
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return -1;
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if (ref1->type > ref2->type)
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return 1;
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if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY ||
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ref1->type == BTRFS_SHARED_BLOCK_REF_KEY)
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ret = comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref1),
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btrfs_delayed_node_to_tree_ref(ref2));
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else
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ret = comp_data_refs(btrfs_delayed_node_to_data_ref(ref1),
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btrfs_delayed_node_to_data_ref(ref2));
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if (ret)
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return ret;
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if (check_seq) {
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if (ref1->seq < ref2->seq)
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return -1;
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if (ref1->seq > ref2->seq)
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return 1;
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}
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return 0;
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}
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/* insert a new ref to head ref rbtree */
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static struct btrfs_delayed_ref_head *htree_insert(struct rb_root_cached *root,
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struct rb_node *node)
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{
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struct rb_node **p = &root->rb_root.rb_node;
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struct rb_node *parent_node = NULL;
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struct btrfs_delayed_ref_head *entry;
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struct btrfs_delayed_ref_head *ins;
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u64 bytenr;
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bool leftmost = true;
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ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node);
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bytenr = ins->bytenr;
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while (*p) {
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parent_node = *p;
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entry = rb_entry(parent_node, struct btrfs_delayed_ref_head,
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href_node);
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if (bytenr < entry->bytenr) {
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p = &(*p)->rb_left;
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} else if (bytenr > entry->bytenr) {
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p = &(*p)->rb_right;
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leftmost = false;
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} else {
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return entry;
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}
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}
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rb_link_node(node, parent_node, p);
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rb_insert_color_cached(node, root, leftmost);
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return NULL;
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}
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static struct btrfs_delayed_ref_node* tree_insert(struct rb_root_cached *root,
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struct btrfs_delayed_ref_node *ins)
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{
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struct rb_node **p = &root->rb_root.rb_node;
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struct rb_node *node = &ins->ref_node;
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struct rb_node *parent_node = NULL;
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struct btrfs_delayed_ref_node *entry;
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bool leftmost = true;
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while (*p) {
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int comp;
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parent_node = *p;
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entry = rb_entry(parent_node, struct btrfs_delayed_ref_node,
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ref_node);
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comp = comp_refs(ins, entry, true);
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if (comp < 0) {
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p = &(*p)->rb_left;
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} else if (comp > 0) {
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p = &(*p)->rb_right;
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leftmost = false;
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} else {
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return entry;
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}
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}
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rb_link_node(node, parent_node, p);
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rb_insert_color_cached(node, root, leftmost);
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return NULL;
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}
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static struct btrfs_delayed_ref_head *find_first_ref_head(
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struct btrfs_delayed_ref_root *dr)
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{
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struct rb_node *n;
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struct btrfs_delayed_ref_head *entry;
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n = rb_first_cached(&dr->href_root);
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if (!n)
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return NULL;
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entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node);
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return entry;
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}
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/*
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* Find a head entry based on bytenr. This returns the delayed ref head if it
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* was able to find one, or NULL if nothing was in that spot. If return_bigger
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* is given, the next bigger entry is returned if no exact match is found.
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*/
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static struct btrfs_delayed_ref_head *find_ref_head(
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struct btrfs_delayed_ref_root *dr, u64 bytenr,
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bool return_bigger)
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{
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struct rb_root *root = &dr->href_root.rb_root;
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struct rb_node *n;
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struct btrfs_delayed_ref_head *entry;
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n = root->rb_node;
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entry = NULL;
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while (n) {
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entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node);
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if (bytenr < entry->bytenr)
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n = n->rb_left;
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else if (bytenr > entry->bytenr)
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n = n->rb_right;
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else
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return entry;
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}
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if (entry && return_bigger) {
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if (bytenr > entry->bytenr) {
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n = rb_next(&entry->href_node);
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if (!n)
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return NULL;
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entry = rb_entry(n, struct btrfs_delayed_ref_head,
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href_node);
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}
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return entry;
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}
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return NULL;
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}
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int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs,
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struct btrfs_delayed_ref_head *head)
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{
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lockdep_assert_held(&delayed_refs->lock);
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if (mutex_trylock(&head->mutex))
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return 0;
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refcount_inc(&head->refs);
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spin_unlock(&delayed_refs->lock);
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mutex_lock(&head->mutex);
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spin_lock(&delayed_refs->lock);
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if (RB_EMPTY_NODE(&head->href_node)) {
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mutex_unlock(&head->mutex);
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btrfs_put_delayed_ref_head(head);
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return -EAGAIN;
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}
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btrfs_put_delayed_ref_head(head);
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return 0;
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}
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static inline void drop_delayed_ref(struct btrfs_trans_handle *trans,
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struct btrfs_delayed_ref_root *delayed_refs,
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struct btrfs_delayed_ref_head *head,
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struct btrfs_delayed_ref_node *ref)
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{
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lockdep_assert_held(&head->lock);
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rb_erase_cached(&ref->ref_node, &head->ref_tree);
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RB_CLEAR_NODE(&ref->ref_node);
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if (!list_empty(&ref->add_list))
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list_del(&ref->add_list);
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ref->in_tree = 0;
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btrfs_put_delayed_ref(ref);
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atomic_dec(&delayed_refs->num_entries);
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}
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static bool merge_ref(struct btrfs_trans_handle *trans,
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struct btrfs_delayed_ref_root *delayed_refs,
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struct btrfs_delayed_ref_head *head,
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struct btrfs_delayed_ref_node *ref,
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u64 seq)
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{
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struct btrfs_delayed_ref_node *next;
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struct rb_node *node = rb_next(&ref->ref_node);
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bool done = false;
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while (!done && node) {
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int mod;
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next = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
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node = rb_next(node);
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if (seq && next->seq >= seq)
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break;
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if (comp_refs(ref, next, false))
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break;
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if (ref->action == next->action) {
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mod = next->ref_mod;
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} else {
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if (ref->ref_mod < next->ref_mod) {
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swap(ref, next);
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done = true;
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}
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mod = -next->ref_mod;
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}
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drop_delayed_ref(trans, delayed_refs, head, next);
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ref->ref_mod += mod;
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if (ref->ref_mod == 0) {
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drop_delayed_ref(trans, delayed_refs, head, ref);
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done = true;
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} else {
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/*
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* Can't have multiples of the same ref on a tree block.
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*/
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WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
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ref->type == BTRFS_SHARED_BLOCK_REF_KEY);
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}
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}
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return done;
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}
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void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
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struct btrfs_delayed_ref_root *delayed_refs,
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struct btrfs_delayed_ref_head *head)
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{
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struct btrfs_fs_info *fs_info = trans->fs_info;
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struct btrfs_delayed_ref_node *ref;
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struct rb_node *node;
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u64 seq = 0;
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lockdep_assert_held(&head->lock);
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if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
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return;
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/* We don't have too many refs to merge for data. */
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if (head->is_data)
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return;
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spin_lock(&fs_info->tree_mod_seq_lock);
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if (!list_empty(&fs_info->tree_mod_seq_list)) {
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struct seq_list *elem;
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elem = list_first_entry(&fs_info->tree_mod_seq_list,
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struct seq_list, list);
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seq = elem->seq;
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}
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spin_unlock(&fs_info->tree_mod_seq_lock);
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again:
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for (node = rb_first_cached(&head->ref_tree); node;
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node = rb_next(node)) {
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ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
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if (seq && ref->seq >= seq)
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continue;
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if (merge_ref(trans, delayed_refs, head, ref, seq))
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goto again;
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}
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}
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int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq)
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{
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struct seq_list *elem;
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int ret = 0;
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spin_lock(&fs_info->tree_mod_seq_lock);
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if (!list_empty(&fs_info->tree_mod_seq_list)) {
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elem = list_first_entry(&fs_info->tree_mod_seq_list,
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struct seq_list, list);
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if (seq >= elem->seq) {
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btrfs_debug(fs_info,
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"holding back delayed_ref %#x.%x, lowest is %#x.%x",
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(u32)(seq >> 32), (u32)seq,
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(u32)(elem->seq >> 32), (u32)elem->seq);
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ret = 1;
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}
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}
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spin_unlock(&fs_info->tree_mod_seq_lock);
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return ret;
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}
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struct btrfs_delayed_ref_head *btrfs_select_ref_head(
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struct btrfs_delayed_ref_root *delayed_refs)
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{
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struct btrfs_delayed_ref_head *head;
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again:
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head = find_ref_head(delayed_refs, delayed_refs->run_delayed_start,
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true);
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if (!head && delayed_refs->run_delayed_start != 0) {
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delayed_refs->run_delayed_start = 0;
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head = find_first_ref_head(delayed_refs);
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}
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if (!head)
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return NULL;
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while (head->processing) {
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struct rb_node *node;
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node = rb_next(&head->href_node);
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if (!node) {
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if (delayed_refs->run_delayed_start == 0)
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return NULL;
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delayed_refs->run_delayed_start = 0;
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goto again;
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}
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head = rb_entry(node, struct btrfs_delayed_ref_head,
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href_node);
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}
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head->processing = 1;
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WARN_ON(delayed_refs->num_heads_ready == 0);
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delayed_refs->num_heads_ready--;
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delayed_refs->run_delayed_start = head->bytenr +
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head->num_bytes;
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return head;
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}
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void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
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struct btrfs_delayed_ref_head *head)
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{
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lockdep_assert_held(&delayed_refs->lock);
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lockdep_assert_held(&head->lock);
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rb_erase_cached(&head->href_node, &delayed_refs->href_root);
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RB_CLEAR_NODE(&head->href_node);
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atomic_dec(&delayed_refs->num_entries);
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delayed_refs->num_heads--;
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if (head->processing == 0)
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delayed_refs->num_heads_ready--;
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}
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/*
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* Helper to insert the ref_node to the tail or merge with tail.
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*
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* Return 0 for insert.
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* Return >0 for merge.
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*/
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static int insert_delayed_ref(struct btrfs_trans_handle *trans,
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struct btrfs_delayed_ref_root *root,
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struct btrfs_delayed_ref_head *href,
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struct btrfs_delayed_ref_node *ref)
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{
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struct btrfs_delayed_ref_node *exist;
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int mod;
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int ret = 0;
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spin_lock(&href->lock);
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exist = tree_insert(&href->ref_tree, ref);
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if (!exist)
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goto inserted;
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/* Now we are sure we can merge */
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ret = 1;
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if (exist->action == ref->action) {
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mod = ref->ref_mod;
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} else {
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/* Need to change action */
|
|
if (exist->ref_mod < ref->ref_mod) {
|
|
exist->action = ref->action;
|
|
mod = -exist->ref_mod;
|
|
exist->ref_mod = ref->ref_mod;
|
|
if (ref->action == BTRFS_ADD_DELAYED_REF)
|
|
list_add_tail(&exist->add_list,
|
|
&href->ref_add_list);
|
|
else if (ref->action == BTRFS_DROP_DELAYED_REF) {
|
|
ASSERT(!list_empty(&exist->add_list));
|
|
list_del(&exist->add_list);
|
|
} else {
|
|
ASSERT(0);
|
|
}
|
|
} else
|
|
mod = -ref->ref_mod;
|
|
}
|
|
exist->ref_mod += mod;
|
|
|
|
/* remove existing tail if its ref_mod is zero */
|
|
if (exist->ref_mod == 0)
|
|
drop_delayed_ref(trans, root, href, exist);
|
|
spin_unlock(&href->lock);
|
|
return ret;
|
|
inserted:
|
|
if (ref->action == BTRFS_ADD_DELAYED_REF)
|
|
list_add_tail(&ref->add_list, &href->ref_add_list);
|
|
atomic_inc(&root->num_entries);
|
|
spin_unlock(&href->lock);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* 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_trans_handle *trans,
|
|
struct btrfs_delayed_ref_head *existing,
|
|
struct btrfs_delayed_ref_head *update,
|
|
int *old_ref_mod_ret)
|
|
{
|
|
struct btrfs_delayed_ref_root *delayed_refs =
|
|
&trans->transaction->delayed_refs;
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
int old_ref_mod;
|
|
|
|
BUG_ON(existing->is_data != update->is_data);
|
|
|
|
spin_lock(&existing->lock);
|
|
if (update->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->must_insert_reserved = update->must_insert_reserved;
|
|
|
|
/*
|
|
* update the num_bytes so we make sure the accounting
|
|
* is done correctly
|
|
*/
|
|
existing->num_bytes = update->num_bytes;
|
|
|
|
}
|
|
|
|
if (update->extent_op) {
|
|
if (!existing->extent_op) {
|
|
existing->extent_op = update->extent_op;
|
|
} else {
|
|
if (update->extent_op->update_key) {
|
|
memcpy(&existing->extent_op->key,
|
|
&update->extent_op->key,
|
|
sizeof(update->extent_op->key));
|
|
existing->extent_op->update_key = true;
|
|
}
|
|
if (update->extent_op->update_flags) {
|
|
existing->extent_op->flags_to_set |=
|
|
update->extent_op->flags_to_set;
|
|
existing->extent_op->update_flags = true;
|
|
}
|
|
btrfs_free_delayed_extent_op(update->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->total_ref_mod;
|
|
if (old_ref_mod_ret)
|
|
*old_ref_mod_ret = old_ref_mod;
|
|
existing->ref_mod += update->ref_mod;
|
|
existing->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->is_data) {
|
|
u64 csum_leaves =
|
|
btrfs_csum_bytes_to_leaves(fs_info,
|
|
existing->num_bytes);
|
|
|
|
if (existing->total_ref_mod >= 0 && old_ref_mod < 0) {
|
|
delayed_refs->pending_csums -= existing->num_bytes;
|
|
btrfs_delayed_refs_rsv_release(fs_info, csum_leaves);
|
|
}
|
|
if (existing->total_ref_mod < 0 && old_ref_mod >= 0) {
|
|
delayed_refs->pending_csums += existing->num_bytes;
|
|
trans->delayed_ref_updates += csum_leaves;
|
|
}
|
|
}
|
|
spin_unlock(&existing->lock);
|
|
}
|
|
|
|
static void init_delayed_ref_head(struct btrfs_delayed_ref_head *head_ref,
|
|
struct btrfs_qgroup_extent_record *qrecord,
|
|
u64 bytenr, u64 num_bytes, u64 ref_root,
|
|
u64 reserved, int action, bool is_data,
|
|
bool is_system)
|
|
{
|
|
int count_mod = 1;
|
|
int must_insert_reserved = 0;
|
|
|
|
/* If reserved is provided, it must be a data extent. */
|
|
BUG_ON(!is_data && reserved);
|
|
|
|
/*
|
|
* 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;
|
|
|
|
refcount_set(&head_ref->refs, 1);
|
|
head_ref->bytenr = bytenr;
|
|
head_ref->num_bytes = num_bytes;
|
|
head_ref->ref_mod = count_mod;
|
|
head_ref->must_insert_reserved = must_insert_reserved;
|
|
head_ref->is_data = is_data;
|
|
head_ref->is_system = is_system;
|
|
head_ref->ref_tree = RB_ROOT_CACHED;
|
|
INIT_LIST_HEAD(&head_ref->ref_add_list);
|
|
RB_CLEAR_NODE(&head_ref->href_node);
|
|
head_ref->processing = 0;
|
|
head_ref->total_ref_mod = count_mod;
|
|
spin_lock_init(&head_ref->lock);
|
|
mutex_init(&head_ref->mutex);
|
|
|
|
if (qrecord) {
|
|
if (ref_root && reserved) {
|
|
qrecord->data_rsv = reserved;
|
|
qrecord->data_rsv_refroot = ref_root;
|
|
}
|
|
qrecord->bytenr = bytenr;
|
|
qrecord->num_bytes = num_bytes;
|
|
qrecord->old_roots = NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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_trans_handle *trans,
|
|
struct btrfs_delayed_ref_head *head_ref,
|
|
struct btrfs_qgroup_extent_record *qrecord,
|
|
int action, int *qrecord_inserted_ret,
|
|
int *old_ref_mod, int *new_ref_mod)
|
|
{
|
|
struct btrfs_delayed_ref_head *existing;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
int qrecord_inserted = 0;
|
|
|
|
delayed_refs = &trans->transaction->delayed_refs;
|
|
|
|
/* Record qgroup extent info if provided */
|
|
if (qrecord) {
|
|
if (btrfs_qgroup_trace_extent_nolock(trans->fs_info,
|
|
delayed_refs, qrecord))
|
|
kfree(qrecord);
|
|
else
|
|
qrecord_inserted = 1;
|
|
}
|
|
|
|
trace_add_delayed_ref_head(trans->fs_info, head_ref, action);
|
|
|
|
existing = htree_insert(&delayed_refs->href_root,
|
|
&head_ref->href_node);
|
|
if (existing) {
|
|
update_existing_head_ref(trans, existing, head_ref,
|
|
old_ref_mod);
|
|
/*
|
|
* 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 (old_ref_mod)
|
|
*old_ref_mod = 0;
|
|
if (head_ref->is_data && head_ref->ref_mod < 0) {
|
|
delayed_refs->pending_csums += head_ref->num_bytes;
|
|
trans->delayed_ref_updates +=
|
|
btrfs_csum_bytes_to_leaves(trans->fs_info,
|
|
head_ref->num_bytes);
|
|
}
|
|
delayed_refs->num_heads++;
|
|
delayed_refs->num_heads_ready++;
|
|
atomic_inc(&delayed_refs->num_entries);
|
|
trans->delayed_ref_updates++;
|
|
}
|
|
if (qrecord_inserted_ret)
|
|
*qrecord_inserted_ret = qrecord_inserted;
|
|
if (new_ref_mod)
|
|
*new_ref_mod = head_ref->total_ref_mod;
|
|
|
|
return head_ref;
|
|
}
|
|
|
|
/*
|
|
* init_delayed_ref_common - Initialize the structure which represents a
|
|
* modification to a an extent.
|
|
*
|
|
* @fs_info: Internal to the mounted filesystem mount structure.
|
|
*
|
|
* @ref: The structure which is going to be initialized.
|
|
*
|
|
* @bytenr: The logical address of the extent for which a modification is
|
|
* going to be recorded.
|
|
*
|
|
* @num_bytes: Size of the extent whose modification is being recorded.
|
|
*
|
|
* @ref_root: The id of the root where this modification has originated, this
|
|
* can be either one of the well-known metadata trees or the
|
|
* subvolume id which references this extent.
|
|
*
|
|
* @action: Can be one of BTRFS_ADD_DELAYED_REF/BTRFS_DROP_DELAYED_REF or
|
|
* BTRFS_ADD_DELAYED_EXTENT
|
|
*
|
|
* @ref_type: Holds the type of the extent which is being recorded, can be
|
|
* one of BTRFS_SHARED_BLOCK_REF_KEY/BTRFS_TREE_BLOCK_REF_KEY
|
|
* when recording a metadata extent or BTRFS_SHARED_DATA_REF_KEY/
|
|
* BTRFS_EXTENT_DATA_REF_KEY when recording data extent
|
|
*/
|
|
static void init_delayed_ref_common(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_delayed_ref_node *ref,
|
|
u64 bytenr, u64 num_bytes, u64 ref_root,
|
|
int action, u8 ref_type)
|
|
{
|
|
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);
|
|
|
|
refcount_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->seq = seq;
|
|
ref->type = ref_type;
|
|
RB_CLEAR_NODE(&ref->ref_node);
|
|
INIT_LIST_HEAD(&ref->add_list);
|
|
}
|
|
|
|
/*
|
|
* 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_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 *old_ref_mod, int *new_ref_mod)
|
|
{
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
struct btrfs_delayed_tree_ref *ref;
|
|
struct btrfs_delayed_ref_head *head_ref;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
struct btrfs_qgroup_extent_record *record = NULL;
|
|
int qrecord_inserted;
|
|
bool is_system = (ref_root == BTRFS_CHUNK_TREE_OBJECTID);
|
|
int ret;
|
|
u8 ref_type;
|
|
|
|
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;
|
|
}
|
|
|
|
if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
|
|
is_fstree(ref_root)) {
|
|
record = kzalloc(sizeof(*record), GFP_NOFS);
|
|
if (!record) {
|
|
kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
|
|
kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
|
|
if (parent)
|
|
ref_type = BTRFS_SHARED_BLOCK_REF_KEY;
|
|
else
|
|
ref_type = BTRFS_TREE_BLOCK_REF_KEY;
|
|
|
|
init_delayed_ref_common(fs_info, &ref->node, bytenr, num_bytes,
|
|
ref_root, action, ref_type);
|
|
ref->root = ref_root;
|
|
ref->parent = parent;
|
|
ref->level = level;
|
|
|
|
init_delayed_ref_head(head_ref, record, bytenr, num_bytes,
|
|
ref_root, 0, action, false, is_system);
|
|
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(trans, head_ref, record,
|
|
action, &qrecord_inserted,
|
|
old_ref_mod, new_ref_mod);
|
|
|
|
ret = insert_delayed_ref(trans, delayed_refs, head_ref, &ref->node);
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* Need to update the delayed_refs_rsv with any changes we may have
|
|
* made.
|
|
*/
|
|
btrfs_update_delayed_refs_rsv(trans);
|
|
|
|
trace_add_delayed_tree_ref(fs_info, &ref->node, ref,
|
|
action == BTRFS_ADD_DELAYED_EXTENT ?
|
|
BTRFS_ADD_DELAYED_REF : action);
|
|
if (ret > 0)
|
|
kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
|
|
|
|
if (qrecord_inserted)
|
|
btrfs_qgroup_trace_extent_post(fs_info, record);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref.
|
|
*/
|
|
int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
|
|
u64 bytenr, u64 num_bytes,
|
|
u64 parent, u64 ref_root,
|
|
u64 owner, u64 offset, u64 reserved, int action,
|
|
int *old_ref_mod, int *new_ref_mod)
|
|
{
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
struct btrfs_delayed_data_ref *ref;
|
|
struct btrfs_delayed_ref_head *head_ref;
|
|
struct btrfs_delayed_ref_root *delayed_refs;
|
|
struct btrfs_qgroup_extent_record *record = NULL;
|
|
int qrecord_inserted;
|
|
int ret;
|
|
u8 ref_type;
|
|
|
|
ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS);
|
|
if (!ref)
|
|
return -ENOMEM;
|
|
|
|
if (parent)
|
|
ref_type = BTRFS_SHARED_DATA_REF_KEY;
|
|
else
|
|
ref_type = BTRFS_EXTENT_DATA_REF_KEY;
|
|
init_delayed_ref_common(fs_info, &ref->node, bytenr, num_bytes,
|
|
ref_root, action, ref_type);
|
|
ref->root = ref_root;
|
|
ref->parent = parent;
|
|
ref->objectid = owner;
|
|
ref->offset = offset;
|
|
|
|
|
|
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;
|
|
}
|
|
|
|
if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
|
|
is_fstree(ref_root)) {
|
|
record = kzalloc(sizeof(*record), GFP_NOFS);
|
|
if (!record) {
|
|
kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
|
|
kmem_cache_free(btrfs_delayed_ref_head_cachep,
|
|
head_ref);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
|
|
init_delayed_ref_head(head_ref, record, bytenr, num_bytes, ref_root,
|
|
reserved, action, true, false);
|
|
head_ref->extent_op = NULL;
|
|
|
|
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(trans, head_ref, record,
|
|
action, &qrecord_inserted,
|
|
old_ref_mod, new_ref_mod);
|
|
|
|
ret = insert_delayed_ref(trans, delayed_refs, head_ref, &ref->node);
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* Need to update the delayed_refs_rsv with any changes we may have
|
|
* made.
|
|
*/
|
|
btrfs_update_delayed_refs_rsv(trans);
|
|
|
|
trace_add_delayed_data_ref(trans->fs_info, &ref->node, ref,
|
|
action == BTRFS_ADD_DELAYED_EXTENT ?
|
|
BTRFS_ADD_DELAYED_REF : action);
|
|
if (ret > 0)
|
|
kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
|
|
|
|
|
|
if (qrecord_inserted)
|
|
return btrfs_qgroup_trace_extent_post(fs_info, record);
|
|
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;
|
|
|
|
init_delayed_ref_head(head_ref, NULL, bytenr, num_bytes, 0, 0,
|
|
BTRFS_UPDATE_DELAYED_HEAD, extent_op->is_data,
|
|
false);
|
|
head_ref->extent_op = extent_op;
|
|
|
|
delayed_refs = &trans->transaction->delayed_refs;
|
|
spin_lock(&delayed_refs->lock);
|
|
|
|
add_delayed_ref_head(trans, head_ref, NULL, BTRFS_UPDATE_DELAYED_HEAD,
|
|
NULL, NULL, NULL);
|
|
|
|
spin_unlock(&delayed_refs->lock);
|
|
|
|
/*
|
|
* Need to update the delayed_refs_rsv with any changes we may have
|
|
* made.
|
|
*/
|
|
btrfs_update_delayed_refs_rsv(trans);
|
|
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_delayed_ref_root *delayed_refs, u64 bytenr)
|
|
{
|
|
return find_ref_head(delayed_refs, bytenr, false);
|
|
}
|
|
|
|
void __cold btrfs_delayed_ref_exit(void)
|
|
{
|
|
kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
|
|
kmem_cache_destroy(btrfs_delayed_tree_ref_cachep);
|
|
kmem_cache_destroy(btrfs_delayed_data_ref_cachep);
|
|
kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
|
|
}
|
|
|
|
int __init 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_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_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_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_MEM_SPREAD, NULL);
|
|
if (!btrfs_delayed_extent_op_cachep)
|
|
goto fail;
|
|
|
|
return 0;
|
|
fail:
|
|
btrfs_delayed_ref_exit();
|
|
return -ENOMEM;
|
|
}
|