Btrfs: Update metadata reservation for delayed allocation
Introduce metadata reservation context for delayed allocation
and update various related functions.
This patch also introduces EXTENT_FIRST_DELALLOC control bit for
set/clear_extent_bit. It tells set/clear_bit_hook whether they
are processing the first extent_state with EXTENT_DELALLOC bit
set. This change is important if set/clear_extent_bit involves
multiple extent_state.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 657df6e..b1822e7 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -64,12 +64,6 @@
struct btrfs_key *key);
static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
int dump_block_groups);
-static int maybe_allocate_chunk(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_space_info *sinfo, u64 num_bytes);
-static int shrink_delalloc(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_space_info *sinfo, u64 to_reclaim);
static noinline int
block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -2880,189 +2874,14 @@
BTRFS_BLOCK_GROUP_DATA);
}
-static u64 calculate_bytes_needed(struct btrfs_root *root, int num_items)
-{
- u64 num_bytes;
- int level;
-
- level = BTRFS_MAX_LEVEL - 2;
- /*
- * NOTE: these calculations are absolutely the worst possible case.
- * This assumes that _every_ item we insert will require a new leaf, and
- * that the tree has grown to its maximum level size.
- */
-
- /*
- * for every item we insert we could insert both an extent item and a
- * extent ref item. Then for ever item we insert, we will need to cow
- * both the original leaf, plus the leaf to the left and right of it.
- *
- * Unless we are talking about the extent root, then we just want the
- * number of items * 2, since we just need the extent item plus its ref.
- */
- if (root == root->fs_info->extent_root)
- num_bytes = num_items * 2;
- else
- num_bytes = (num_items + (2 * num_items)) * 3;
-
- /*
- * num_bytes is total number of leaves we could need times the leaf
- * size, and then for every leaf we could end up cow'ing 2 nodes per
- * level, down to the leaf level.
- */
- num_bytes = (num_bytes * root->leafsize) +
- (num_bytes * (level * 2)) * root->nodesize;
-
- return num_bytes;
-}
-
-/*
- * Unreserve metadata space for delalloc. If we have less reserved credits than
- * we have extents, this function does nothing.
- */
-int btrfs_unreserve_metadata_for_delalloc(struct btrfs_root *root,
- struct inode *inode, int num_items)
-{
- struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_space_info *meta_sinfo;
- u64 num_bytes;
- u64 alloc_target;
- bool bug = false;
-
- /* get the space info for where the metadata will live */
- alloc_target = btrfs_get_alloc_profile(root, 0);
- meta_sinfo = __find_space_info(info, alloc_target);
-
- num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
- num_items);
-
- spin_lock(&meta_sinfo->lock);
- spin_lock(&BTRFS_I(inode)->accounting_lock);
- if (BTRFS_I(inode)->reserved_extents <=
- BTRFS_I(inode)->outstanding_extents) {
- spin_unlock(&BTRFS_I(inode)->accounting_lock);
- spin_unlock(&meta_sinfo->lock);
- return 0;
- }
- spin_unlock(&BTRFS_I(inode)->accounting_lock);
-
- BTRFS_I(inode)->reserved_extents -= num_items;
- BUG_ON(BTRFS_I(inode)->reserved_extents < 0);
-
- if (meta_sinfo->bytes_delalloc < num_bytes) {
- bug = true;
- meta_sinfo->bytes_delalloc = 0;
- } else {
- meta_sinfo->bytes_delalloc -= num_bytes;
- }
- spin_unlock(&meta_sinfo->lock);
-
- BUG_ON(bug);
-
- return 0;
-}
-
-static void check_force_delalloc(struct btrfs_space_info *meta_sinfo)
-{
- u64 thresh;
-
- thresh = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
- meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
- meta_sinfo->bytes_super + meta_sinfo->bytes_root +
- meta_sinfo->bytes_may_use;
-
- thresh = meta_sinfo->total_bytes - thresh;
- thresh *= 80;
- do_div(thresh, 100);
- if (thresh <= meta_sinfo->bytes_delalloc)
- meta_sinfo->force_delalloc = 1;
- else
- meta_sinfo->force_delalloc = 0;
-}
-
-/*
- * Reserve metadata space for delalloc.
- */
-int btrfs_reserve_metadata_for_delalloc(struct btrfs_root *root,
- struct inode *inode, int num_items)
-{
- struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_space_info *meta_sinfo;
- u64 num_bytes;
- u64 used;
- u64 alloc_target;
- int flushed = 0;
- int force_delalloc;
-
- /* get the space info for where the metadata will live */
- alloc_target = btrfs_get_alloc_profile(root, 0);
- meta_sinfo = __find_space_info(info, alloc_target);
-
- num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
- num_items);
-again:
- spin_lock(&meta_sinfo->lock);
-
- force_delalloc = meta_sinfo->force_delalloc;
-
- if (unlikely(!meta_sinfo->bytes_root))
- meta_sinfo->bytes_root = calculate_bytes_needed(root, 6);
-
- if (!flushed)
- meta_sinfo->bytes_delalloc += num_bytes;
-
- used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
- meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
- meta_sinfo->bytes_super + meta_sinfo->bytes_root +
- meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc;
-
- if (used > meta_sinfo->total_bytes) {
- flushed++;
-
- if (flushed == 1) {
- if (maybe_allocate_chunk(NULL, root, meta_sinfo,
- num_bytes))
- goto again;
- flushed++;
- } else {
- spin_unlock(&meta_sinfo->lock);
- }
-
- if (flushed == 2) {
- filemap_flush(inode->i_mapping);
- goto again;
- } else if (flushed == 3) {
- shrink_delalloc(NULL, root, meta_sinfo, num_bytes);
- goto again;
- }
- spin_lock(&meta_sinfo->lock);
- meta_sinfo->bytes_delalloc -= num_bytes;
- spin_unlock(&meta_sinfo->lock);
- printk(KERN_ERR "enospc, has %d, reserved %d\n",
- BTRFS_I(inode)->outstanding_extents,
- BTRFS_I(inode)->reserved_extents);
- dump_space_info(meta_sinfo, 0, 0);
- return -ENOSPC;
- }
-
- BTRFS_I(inode)->reserved_extents += num_items;
- check_force_delalloc(meta_sinfo);
- spin_unlock(&meta_sinfo->lock);
-
- if (!flushed && force_delalloc)
- filemap_flush(inode->i_mapping);
-
- return 0;
-}
-
/*
* This will check the space that the inode allocates from to make sure we have
* enough space for bytes.
*/
-int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
- u64 bytes)
+int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
{
struct btrfs_space_info *data_sinfo;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
u64 used;
int ret = 0, committed = 0;
@@ -3147,12 +2966,13 @@
}
/*
- * if there was an error for whatever reason after calling
- * btrfs_check_data_free_space, call this so we can cleanup the counters.
+ * called when we are clearing an delalloc extent from the
+ * inode's io_tree or there was an error for whatever reason
+ * after calling btrfs_check_data_free_space
*/
-void btrfs_free_reserved_data_space(struct btrfs_root *root,
- struct inode *inode, u64 bytes)
+void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_space_info *data_sinfo;
/* make sure bytes are sectorsize aligned */
@@ -3165,48 +2985,6 @@
spin_unlock(&data_sinfo->lock);
}
-/* called when we are adding a delalloc extent to the inode's io_tree */
-void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
- u64 bytes)
-{
- struct btrfs_space_info *data_sinfo;
-
- /* get the space info for where this inode will be storing its data */
- data_sinfo = BTRFS_I(inode)->space_info;
-
- /* make sure we have enough space to handle the data first */
- spin_lock(&data_sinfo->lock);
- data_sinfo->bytes_delalloc += bytes;
-
- /*
- * we are adding a delalloc extent without calling
- * btrfs_check_data_free_space first. This happens on a weird
- * writepage condition, but shouldn't hurt our accounting
- */
- if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) {
- data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes;
- BTRFS_I(inode)->reserved_bytes = 0;
- } else {
- data_sinfo->bytes_may_use -= bytes;
- BTRFS_I(inode)->reserved_bytes -= bytes;
- }
-
- spin_unlock(&data_sinfo->lock);
-}
-
-/* called when we are clearing an delalloc extent from the inode's io_tree */
-void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
- u64 bytes)
-{
- struct btrfs_space_info *info;
-
- info = BTRFS_I(inode)->space_info;
-
- spin_lock(&info->lock);
- info->bytes_delalloc -= bytes;
- spin_unlock(&info->lock);
-}
-
static void force_metadata_allocation(struct btrfs_fs_info *info)
{
struct list_head *head = &info->space_info;
@@ -3331,18 +3109,19 @@
* shrink metadata reservation for delalloc
*/
static int shrink_delalloc(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_space_info *sinfo, u64 to_reclaim)
+ struct btrfs_root *root, u64 to_reclaim)
{
+ struct btrfs_block_rsv *block_rsv;
u64 reserved;
u64 max_reclaim;
u64 reclaimed = 0;
int pause = 1;
int ret;
- spin_lock(&sinfo->lock);
- reserved = sinfo->bytes_delalloc;
- spin_unlock(&sinfo->lock);
+ block_rsv = &root->fs_info->delalloc_block_rsv;
+ spin_lock(&block_rsv->lock);
+ reserved = block_rsv->reserved;
+ spin_unlock(&block_rsv->lock);
if (reserved == 0)
return 0;
@@ -3361,11 +3140,11 @@
pause = 1;
}
- spin_lock(&sinfo->lock);
- if (reserved > sinfo->bytes_delalloc)
- reclaimed = reserved - sinfo->bytes_delalloc;
- reserved = sinfo->bytes_delalloc;
- spin_unlock(&sinfo->lock);
+ spin_lock(&block_rsv->lock);
+ if (reserved > block_rsv->reserved)
+ reclaimed = reserved - block_rsv->reserved;
+ reserved = block_rsv->reserved;
+ spin_unlock(&block_rsv->lock);
if (reserved == 0 || reclaimed >= max_reclaim)
break;
@@ -3394,7 +3173,7 @@
if (trans && trans->transaction->in_commit)
return -ENOSPC;
- ret = shrink_delalloc(trans, root, space_info, num_bytes);
+ ret = shrink_delalloc(trans, root, num_bytes);
if (ret)
return ret;
@@ -3754,6 +3533,108 @@
return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
}
+static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
+{
+ return num_bytes >>= 3;
+}
+
+int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
+ u64 to_reserve;
+ int nr_extents;
+ int retries = 0;
+ int ret;
+
+ if (btrfs_transaction_in_commit(root->fs_info))
+ schedule_timeout(1);
+
+ num_bytes = ALIGN(num_bytes, root->sectorsize);
+again:
+ spin_lock(&BTRFS_I(inode)->accounting_lock);
+ nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
+ if (nr_extents > BTRFS_I(inode)->reserved_extents) {
+ nr_extents -= BTRFS_I(inode)->reserved_extents;
+ to_reserve = calc_trans_metadata_size(root, nr_extents);
+ } else {
+ nr_extents = 0;
+ to_reserve = 0;
+ }
+
+ to_reserve += calc_csum_metadata_size(inode, num_bytes);
+ ret = reserve_metadata_bytes(block_rsv, to_reserve);
+ if (ret) {
+ spin_unlock(&BTRFS_I(inode)->accounting_lock);
+ ret = should_retry_reserve(NULL, root, block_rsv, to_reserve,
+ &retries);
+ if (ret > 0)
+ goto again;
+ return ret;
+ }
+
+ BTRFS_I(inode)->reserved_extents += nr_extents;
+ atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+ spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+ block_rsv_add_bytes(block_rsv, to_reserve, 1);
+
+ if (block_rsv->size > 512 * 1024 * 1024)
+ shrink_delalloc(NULL, root, to_reserve);
+
+ return 0;
+}
+
+void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ u64 to_free;
+ int nr_extents;
+
+ num_bytes = ALIGN(num_bytes, root->sectorsize);
+ atomic_dec(&BTRFS_I(inode)->outstanding_extents);
+
+ spin_lock(&BTRFS_I(inode)->accounting_lock);
+ nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
+ if (nr_extents < BTRFS_I(inode)->reserved_extents) {
+ nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
+ BTRFS_I(inode)->reserved_extents -= nr_extents;
+ } else {
+ nr_extents = 0;
+ }
+ spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+ to_free = calc_csum_metadata_size(inode, num_bytes);
+ if (nr_extents > 0)
+ to_free += calc_trans_metadata_size(root, nr_extents);
+
+ btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
+ to_free);
+}
+
+int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
+{
+ int ret;
+
+ ret = btrfs_check_data_free_space(inode, num_bytes);
+ if (ret)
+ return ret;
+
+ ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
+ if (ret) {
+ btrfs_free_reserved_data_space(inode, num_bytes);
+ return ret;
+ }
+
+ return 0;
+}
+
+void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
+{
+ btrfs_delalloc_release_metadata(inode, num_bytes);
+ btrfs_free_reserved_data_space(inode, num_bytes);
+}
+
static int update_block_group(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, int alloc)
