Btrfs: wait on ordered extents at the last possible moment
Since we don't actually copy the extent information from the source tree in
the fast case we don't need to wait for ordered io to be completed in order
to fsync, we just need to wait for the io to be completed. So when we're
logging our file just attach all of the ordered extents to the log, and then
when the log syncs just wait for IO_DONE on the ordered extents and then
write the super. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 547b7b0..411c8d9 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1623,6 +1623,9 @@
struct list_head root_list;
+ spinlock_t log_extents_lock[2];
+ struct list_head logged_list[2];
+
spinlock_t orphan_lock;
atomic_t orphan_inodes;
struct btrfs_block_rsv *orphan_block_rsv;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a762f91..1db8a99 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1178,9 +1178,13 @@
INIT_LIST_HEAD(&root->dirty_list);
INIT_LIST_HEAD(&root->root_list);
+ INIT_LIST_HEAD(&root->logged_list[0]);
+ INIT_LIST_HEAD(&root->logged_list[1]);
spin_lock_init(&root->orphan_lock);
spin_lock_init(&root->inode_lock);
spin_lock_init(&root->accounting_lock);
+ spin_lock_init(&root->log_extents_lock[0]);
+ spin_lock_init(&root->log_extents_lock[1]);
mutex_init(&root->objectid_mutex);
mutex_init(&root->log_mutex);
init_waitqueue_head(&root->log_writer_wait);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b06d289..083abca 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1655,16 +1655,21 @@
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret = 0;
struct btrfs_trans_handle *trans;
+ bool full_sync = 0;
trace_btrfs_sync_file(file, datasync);
/*
* We write the dirty pages in the range and wait until they complete
* out of the ->i_mutex. If so, we can flush the dirty pages by
- * multi-task, and make the performance up.
+ * multi-task, and make the performance up. See
+ * btrfs_wait_ordered_range for an explanation of the ASYNC check.
*/
atomic_inc(&BTRFS_I(inode)->sync_writers);
- ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
+ ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
+ if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+ &BTRFS_I(inode)->runtime_flags))
+ ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
atomic_dec(&BTRFS_I(inode)->sync_writers);
if (ret)
return ret;
@@ -1676,7 +1681,10 @@
* range being left.
*/
atomic_inc(&root->log_batch);
- btrfs_wait_ordered_range(inode, start, end - start + 1);
+ full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
+ &BTRFS_I(inode)->runtime_flags);
+ if (full_sync)
+ btrfs_wait_ordered_range(inode, start, end - start + 1);
atomic_inc(&root->log_batch);
/*
@@ -1743,13 +1751,25 @@
if (ret != BTRFS_NO_LOG_SYNC) {
if (ret > 0) {
+ /*
+ * If we didn't already wait for ordered extents we need
+ * to do that now.
+ */
+ if (!full_sync)
+ btrfs_wait_ordered_range(inode, start,
+ end - start + 1);
ret = btrfs_commit_transaction(trans, root);
} else {
ret = btrfs_sync_log(trans, root);
- if (ret == 0)
+ if (ret == 0) {
ret = btrfs_end_transaction(trans, root);
- else
+ } else {
+ if (!full_sync)
+ btrfs_wait_ordered_range(inode, start,
+ end -
+ start + 1);
ret = btrfs_commit_transaction(trans, root);
+ }
}
} else {
ret = btrfs_end_transaction(trans, root);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 35d1524..31a871e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -700,6 +700,8 @@
em->start = async_extent->start;
em->len = async_extent->ram_size;
em->orig_start = em->start;
+ em->mod_start = em->start;
+ em->mod_len = em->len;
em->block_start = ins.objectid;
em->block_len = ins.offset;
@@ -892,6 +894,8 @@
em->orig_start = em->start;
ram_size = ins.offset;
em->len = ins.offset;
+ em->mod_start = em->start;
+ em->mod_len = em->len;
em->block_start = ins.objectid;
em->block_len = ins.offset;
@@ -1338,6 +1342,8 @@
em->block_start = disk_bytenr;
em->orig_block_len = disk_num_bytes;
em->bdev = root->fs_info->fs_devices->latest_bdev;
+ em->mod_start = em->start;
+ em->mod_len = em->len;
set_bit(EXTENT_FLAG_PINNED, &em->flags);
set_bit(EXTENT_FLAG_FILLING, &em->flags);
em->generation = -1;
@@ -5966,6 +5972,8 @@
em->start = start;
em->orig_start = orig_start;
+ em->mod_start = start;
+ em->mod_len = len;
em->len = len;
em->block_len = block_len;
em->block_start = block_start;
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index e5ed567..f14b174 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -196,6 +196,9 @@
entry->file_offset = file_offset;
entry->start = start;
entry->len = len;
+ if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) &&
+ !(type == BTRFS_ORDERED_NOCOW))
+ entry->csum_bytes_left = disk_len;
entry->disk_len = disk_len;
entry->bytes_left = len;
entry->inode = igrab(inode);
@@ -213,6 +216,7 @@
INIT_LIST_HEAD(&entry->root_extent_list);
INIT_LIST_HEAD(&entry->work_list);
init_completion(&entry->completion);
+ INIT_LIST_HEAD(&entry->log_list);
trace_btrfs_ordered_extent_add(inode, entry);
@@ -270,6 +274,10 @@
tree = &BTRFS_I(inode)->ordered_tree;
spin_lock_irq(&tree->lock);
list_add_tail(&sum->list, &entry->list);
+ WARN_ON(entry->csum_bytes_left < sum->len);
+ entry->csum_bytes_left -= sum->len;
+ if (entry->csum_bytes_left == 0)
+ wake_up(&entry->wait);
spin_unlock_irq(&tree->lock);
}
@@ -405,6 +413,66 @@
return ret == 0;
}
+/* Needs to either be called under a log transaction or the log_mutex */
+void btrfs_get_logged_extents(struct btrfs_root *log, struct inode *inode)
+{
+ struct btrfs_ordered_inode_tree *tree;
+ struct btrfs_ordered_extent *ordered;
+ struct rb_node *n;
+ int index = log->log_transid % 2;
+
+ tree = &BTRFS_I(inode)->ordered_tree;
+ spin_lock_irq(&tree->lock);
+ for (n = rb_first(&tree->tree); n; n = rb_next(n)) {
+ ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
+ spin_lock(&log->log_extents_lock[index]);
+ if (list_empty(&ordered->log_list)) {
+ list_add_tail(&ordered->log_list, &log->logged_list[index]);
+ atomic_inc(&ordered->refs);
+ }
+ spin_unlock(&log->log_extents_lock[index]);
+ }
+ spin_unlock_irq(&tree->lock);
+}
+
+void btrfs_wait_logged_extents(struct btrfs_root *log, u64 transid)
+{
+ struct btrfs_ordered_extent *ordered;
+ int index = transid % 2;
+
+ spin_lock_irq(&log->log_extents_lock[index]);
+ while (!list_empty(&log->logged_list[index])) {
+ ordered = list_first_entry(&log->logged_list[index],
+ struct btrfs_ordered_extent,
+ log_list);
+ list_del_init(&ordered->log_list);
+ spin_unlock_irq(&log->log_extents_lock[index]);
+ wait_event(ordered->wait, test_bit(BTRFS_ORDERED_IO_DONE,
+ &ordered->flags));
+ btrfs_put_ordered_extent(ordered);
+ spin_lock_irq(&log->log_extents_lock[index]);
+ }
+ spin_unlock_irq(&log->log_extents_lock[index]);
+}
+
+void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid)
+{
+ struct btrfs_ordered_extent *ordered;
+ int index = transid % 2;
+
+ spin_lock_irq(&log->log_extents_lock[index]);
+ while (!list_empty(&log->logged_list[index])) {
+ ordered = list_first_entry(&log->logged_list[index],
+ struct btrfs_ordered_extent,
+ log_list);
+ list_del_init(&ordered->log_list);
+ spin_unlock_irq(&log->log_extents_lock[index]);
+ btrfs_put_ordered_extent(ordered);
+ spin_lock_irq(&log->log_extents_lock[index]);
+ }
+ spin_unlock_irq(&log->log_extents_lock[index]);
+}
+
/*
* used to drop a reference on an ordered extent. This will free
* the extent if the last reference is dropped
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index efc7c29..d523dbd 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -79,6 +79,8 @@
#define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates wether this ordered extent
* has done its due diligence in updating
* the isize. */
+#define BTRFS_ORDERED_LOGGED_CSUM 8 /* We've logged the csums on this ordered
+ ordered extent */
struct btrfs_ordered_extent {
/* logical offset in the file */
@@ -96,6 +98,9 @@
/* number of bytes that still need writing */
u64 bytes_left;
+ /* number of bytes that still need csumming */
+ u64 csum_bytes_left;
+
/*
* the end of the ordered extent which is behind it but
* didn't update disk_i_size. Please see the comment of
@@ -118,6 +123,9 @@
/* list of checksums for insertion when the extent io is done */
struct list_head list;
+ /* If we need to wait on this to be done */
+ struct list_head log_list;
+
/* used to wait for the BTRFS_ORDERED_COMPLETE bit */
wait_queue_head_t wait;
@@ -194,6 +202,9 @@
struct btrfs_root *root,
struct inode *inode);
void btrfs_wait_ordered_extents(struct btrfs_root *root, int delay_iput);
+void btrfs_get_logged_extents(struct btrfs_root *log, struct inode *inode);
+void btrfs_wait_logged_extents(struct btrfs_root *log, u64 transid);
+void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid);
int __init ordered_data_init(void);
void ordered_data_exit(void);
#endif
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 9027bb1..7de720d 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2281,6 +2281,7 @@
unsigned long log_transid = 0;
mutex_lock(&root->log_mutex);
+ log_transid = root->log_transid;
index1 = root->log_transid % 2;
if (atomic_read(&root->log_commit[index1])) {
wait_log_commit(trans, root, root->log_transid);
@@ -2308,11 +2309,11 @@
/* bail out if we need to do a full commit */
if (root->fs_info->last_trans_log_full_commit == trans->transid) {
ret = -EAGAIN;
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&root->log_mutex);
goto out;
}
- log_transid = root->log_transid;
if (log_transid % 2 == 0)
mark = EXTENT_DIRTY;
else
@@ -2324,6 +2325,7 @@
ret = btrfs_write_marked_extents(log, &log->dirty_log_pages, mark);
if (ret) {
btrfs_abort_transaction(trans, root, ret);
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&root->log_mutex);
goto out;
}
@@ -2363,6 +2365,7 @@
}
root->fs_info->last_trans_log_full_commit = trans->transid;
btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&log_root_tree->log_mutex);
ret = -EAGAIN;
goto out;
@@ -2373,6 +2376,7 @@
btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
wait_log_commit(trans, log_root_tree,
log_root_tree->log_transid);
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&log_root_tree->log_mutex);
ret = 0;
goto out;
@@ -2392,6 +2396,7 @@
*/
if (root->fs_info->last_trans_log_full_commit == trans->transid) {
btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&log_root_tree->log_mutex);
ret = -EAGAIN;
goto out_wake_log_root;
@@ -2402,10 +2407,12 @@
EXTENT_DIRTY | EXTENT_NEW);
if (ret) {
btrfs_abort_transaction(trans, root, ret);
+ btrfs_free_logged_extents(log, log_transid);
mutex_unlock(&log_root_tree->log_mutex);
goto out_wake_log_root;
}
btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
+ btrfs_wait_logged_extents(log, log_transid);
btrfs_set_super_log_root(root->fs_info->super_for_commit,
log_root_tree->node->start);
@@ -2475,6 +2482,14 @@
EXTENT_DIRTY | EXTENT_NEW, GFP_NOFS);
}
+ /*
+ * We may have short-circuited the log tree with the full commit logic
+ * and left ordered extents on our list, so clear these out to keep us
+ * from leaking inodes and memory.
+ */
+ btrfs_free_logged_extents(log, 0);
+ btrfs_free_logged_extents(log, 1);
+
free_extent_buffer(log->node);
kfree(log);
}
@@ -3271,14 +3286,18 @@
struct btrfs_root *log = root->log_root;
struct btrfs_file_extent_item *fi;
struct extent_buffer *leaf;
+ struct btrfs_ordered_extent *ordered;
struct list_head ordered_sums;
struct btrfs_map_token token;
struct btrfs_key key;
- u64 csum_offset = em->mod_start - em->start;
- u64 csum_len = em->mod_len;
+ u64 mod_start = em->mod_start;
+ u64 mod_len = em->mod_len;
+ u64 csum_offset;
+ u64 csum_len;
u64 extent_offset = em->start - em->orig_start;
u64 block_len;
int ret;
+ int index = log->log_transid % 2;
bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
INIT_LIST_HEAD(&ordered_sums);
@@ -3362,6 +3381,92 @@
csum_len = block_len;
}
+ /*
+ * First check and see if our csums are on our outstanding ordered
+ * extents.
+ */
+again:
+ spin_lock_irq(&log->log_extents_lock[index]);
+ list_for_each_entry(ordered, &log->logged_list[index], log_list) {
+ struct btrfs_ordered_sum *sum;
+
+ if (!mod_len)
+ break;
+
+ if (ordered->inode != inode)
+ continue;
+
+ if (ordered->file_offset + ordered->len <= mod_start ||
+ mod_start + mod_len <= ordered->file_offset)
+ continue;
+
+ /*
+ * We are going to copy all the csums on this ordered extent, so
+ * go ahead and adjust mod_start and mod_len in case this
+ * ordered extent has already been logged.
+ */
+ if (ordered->file_offset > mod_start) {
+ if (ordered->file_offset + ordered->len >=
+ mod_start + mod_len)
+ mod_len = ordered->file_offset - mod_start;
+ /*
+ * If we have this case
+ *
+ * |--------- logged extent ---------|
+ * |----- ordered extent ----|
+ *
+ * Just don't mess with mod_start and mod_len, we'll
+ * just end up logging more csums than we need and it
+ * will be ok.
+ */
+ } else {
+ if (ordered->file_offset + ordered->len <
+ mod_start + mod_len) {
+ mod_len = (mod_start + mod_len) -
+ (ordered->file_offset + ordered->len);
+ mod_start = ordered->file_offset +
+ ordered->len;
+ } else {
+ mod_len = 0;
+ }
+ }
+
+ /*
+ * To keep us from looping for the above case of an ordered
+ * extent that falls inside of the logged extent.
+ */
+ if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM,
+ &ordered->flags))
+ continue;
+ atomic_inc(&ordered->refs);
+ spin_unlock_irq(&log->log_extents_lock[index]);
+ /*
+ * we've dropped the lock, we must either break or
+ * start over after this.
+ */
+
+ wait_event(ordered->wait, ordered->csum_bytes_left == 0);
+
+ list_for_each_entry(sum, &ordered->list, list) {
+ ret = btrfs_csum_file_blocks(trans, log, sum);
+ if (ret) {
+ btrfs_put_ordered_extent(ordered);
+ goto unlocked;
+ }
+ }
+ btrfs_put_ordered_extent(ordered);
+ goto again;
+
+ }
+ spin_unlock_irq(&log->log_extents_lock[index]);
+unlocked:
+
+ if (!mod_len || ret)
+ return ret;
+
+ csum_offset = mod_start - em->start;
+ csum_len = mod_len;
+
/* block start is already adjusted for the file extent offset. */
ret = btrfs_lookup_csums_range(log->fs_info->csum_root,
em->block_start + csum_offset,
@@ -3393,6 +3498,7 @@
struct extent_map_tree *tree = &BTRFS_I(inode)->extent_tree;
u64 test_gen;
int ret = 0;
+ int num = 0;
INIT_LIST_HEAD(&extents);
@@ -3401,16 +3507,31 @@
list_for_each_entry_safe(em, n, &tree->modified_extents, list) {
list_del_init(&em->list);
+
+ /*
+ * Just an arbitrary number, this can be really CPU intensive
+ * once we start getting a lot of extents, and really once we
+ * have a bunch of extents we just want to commit since it will
+ * be faster.
+ */
+ if (++num > 32768) {
+ list_del_init(&tree->modified_extents);
+ ret = -EFBIG;
+ goto process;
+ }
+
if (em->generation <= test_gen)
continue;
/* Need a ref to keep it from getting evicted from cache */
atomic_inc(&em->refs);
set_bit(EXTENT_FLAG_LOGGING, &em->flags);
list_add_tail(&em->list, &extents);
+ num++;
}
list_sort(NULL, &extents, extent_cmp);
+process:
while (!list_empty(&extents)) {
em = list_entry(extents.next, struct extent_map, list);
@@ -3513,6 +3634,8 @@
mutex_lock(&BTRFS_I(inode)->log_mutex);
+ btrfs_get_logged_extents(log, inode);
+
/*
* a brute force approach to making sure we get the most uptodate
* copies of everything.
@@ -3656,6 +3779,8 @@
BTRFS_I(inode)->logged_trans = trans->transid;
BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->last_sub_trans;
out_unlock:
+ if (err)
+ btrfs_free_logged_extents(log, log->log_transid);
mutex_unlock(&BTRFS_I(inode)->log_mutex);
btrfs_free_path(path);
@@ -3822,7 +3947,6 @@
end_trans:
dput(old_parent);
if (ret < 0) {
- WARN_ON(ret != -ENOSPC);
root->fs_info->last_trans_log_full_commit = trans->transid;
ret = 1;
}