On 2018年08月06日 13:25, Misono Tomohiro wrote:
> There are two members in struct btrfs_root which indicate root's
> objectid: ->objectid and ->root_key.objectid.
>
> They are both set to the same value in __setup_root():
> static void __setup_root(struct btrfs_root *root,
> struct btrfs_fs_info *fs_info,
> u64 objectid)
> {
> ...
> root->objectid = objectid;
> ...
> root->root_key.objectid = objecitd;
> ...
> }
> and not changed to other value after initialization.
>
> grep in btrfs directory shows both are used in many places:
> $ grep -rI "root->root_key.objectid" | wc -l
> 133
> $ grep -rI "root->objectid" | wc -l
> 55
> (4.17, inc. some noise)
>
> It is confusing to have two similar variable names and it seems
> that there is no rule about which should be used in a certain case.
>
> Since ->root_key itself is needed for tree reloc tree, let's remove
> 'objecitd' member and unify code to use ->root_key.objectid in all places.
It's a pretty nice move, just a small nitpick about __setup_root()
inlined later.
(And a personal crazy idea no need to address)
>
> Signed-off-by: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxxxxx>
Feel free to add my tag:
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
> ---
> Although being fundamentally independent, this is based on the
> patch: https://patchwork.kernel.org/patch/10556485/
> since it also touches root->objectid.
>
> fs/btrfs/backref.c | 5 +++--
> fs/btrfs/btrfs_inode.h | 8 ++++----
> fs/btrfs/ctree.c | 2 +-
> fs/btrfs/ctree.h | 1 -
> fs/btrfs/delayed-inode.c | 5 +++--
> fs/btrfs/disk-io.c | 5 ++---
> fs/btrfs/export.c | 4 ++--
> fs/btrfs/inode.c | 2 +-
> fs/btrfs/ioctl.c | 2 +-
> fs/btrfs/qgroup.c | 23 ++++++++++++-----------
> fs/btrfs/ref-verify.c | 8 ++++----
> fs/btrfs/relocation.c | 3 ++-
> fs/btrfs/send.c | 16 ++++++++--------
> fs/btrfs/super.c | 6 ++++--
> fs/btrfs/transaction.c | 4 ++--
> include/trace/events/btrfs.h | 15 ++++++++-------
> 16 files changed, 57 insertions(+), 52 deletions(-)
> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
> index 318be7864072..5be7c2bc45c0 100644
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -1202,7 +1202,6 @@ struct btrfs_root {
> int last_log_commit;
> pid_t log_start_pid;
>
> - u64 objectid;
Off topic crazy idea here.
I think it is a little crazy, but it should save a lot of objectid
related modification:
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 118346aceea9..e6d70f2309a3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1166,7 +1166,10 @@ struct btrfs_root {
unsigned long state;
struct btrfs_root_item root_item;
- struct btrfs_key root_key;
+ union {
+ struct btrfs_key root_key;
+ u64 objectid;
+ };
struct btrfs_fs_info *fs_info;
struct extent_io_tree dirty_log_pages;
@@ -1198,7 +1201,6 @@ struct btrfs_root {
int last_log_commit;
pid_t log_start_pid;
- u64 objectid;
u64 last_trans;
u32 type;
I'm not sure if this is a really crazy idea or a dirty hack to reduce
some modification.
Anyway, I'm completely fine with current patch.
> u64 last_trans;
>
> u32 type;
> diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
> index f51b509f2d9b..07187e4ab600 100644
> --- a/fs/btrfs/delayed-inode.c
> +++ b/fs/btrfs/delayed-inode.c
> @@ -1462,7 +1462,7 @@ int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
> if (unlikely(ret)) {
> btrfs_err(trans->fs_info,
> "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
> - name_len, name, delayed_node->root->objectid,
> + name_len, name, delayed_node->root->root_key.objectid,
> delayed_node->inode_id, ret);
> BUG();
> }
> @@ -1533,7 +1533,8 @@ int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
> if (unlikely(ret)) {
> btrfs_err(trans->fs_info,
> "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
> - index, node->root->objectid, node->inode_id, ret);
> + index, node->root->root_key.objectid,
> + node->inode_id, ret);
> BUG();
> }
> mutex_unlock(&node->mutex);
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 468365dd3b59..3fe87f67869b 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -125,8 +125,8 @@ struct async_submit_bio {
> * Different roots are used for different purposes and may nest inside each
> * other and they require separate keysets. As lockdep keys should be
> * static, assign keysets according to the purpose of the root as indicated
> - * by btrfs_root->objectid. This ensures that all special purpose roots
> - * have separate keysets.
> + * by btrfs_root->root_key.objectid. This ensures that all special purpose
> + * roots have separate keysets.
> *
> * Lock-nesting across peer nodes is always done with the immediate parent
> * node locked thus preventing deadlock. As lockdep doesn't know this, use
> @@ -1148,7 +1148,6 @@ static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
Since objectid is not really used and root->root_key can be set later by
btrfs_create_tree() or alloc_log_tree().
What about either removing @objectid parameter or replace it with @root_key?
Thanks,
Qu
> root->state = 0;
> root->orphan_cleanup_state = 0;
>
> - root->objectid = objectid;
> root->last_trans = 0;
> root->highest_objectid = 0;
> root->nr_delalloc_inodes = 0;
> diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
> index 1f3755b3a37a..ddf28ecf17f9 100644
> --- a/fs/btrfs/export.c
> +++ b/fs/btrfs/export.c
> @@ -33,7 +33,7 @@ static int btrfs_encode_fh(struct inode *inode, u32 *fh, int *max_len,
> type = FILEID_BTRFS_WITHOUT_PARENT;
>
> fid->objectid = btrfs_ino(BTRFS_I(inode));
> - fid->root_objectid = BTRFS_I(inode)->root->objectid;
> + fid->root_objectid = BTRFS_I(inode)->root->root_key.objectid;
> fid->gen = inode->i_generation;
>
> if (parent) {
> @@ -41,7 +41,7 @@ static int btrfs_encode_fh(struct inode *inode, u32 *fh, int *max_len,
>
> fid->parent_objectid = BTRFS_I(parent)->location.objectid;
> fid->parent_gen = parent->i_generation;
> - parent_root_id = BTRFS_I(parent)->root->objectid;
> + parent_root_id = BTRFS_I(parent)->root->root_key.objectid;
>
> if (parent_root_id != fid->root_objectid) {
> fid->parent_root_objectid = parent_root_id;
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 3f51ddc18f98..78111d972af8 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -6613,7 +6613,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
> int drop_inode = 0;
>
> /* do not allow sys_link's with other subvols of the same device */
> - if (root->objectid != BTRFS_I(inode)->root->objectid)
> + if (root->root_key.objectid != BTRFS_I(inode)->root->root_key.objectid)
> return -EXDEV;
>
> if (inode->i_nlink >= BTRFS_LINK_MAX)
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 6eaadddaca9f..8ab30c62df36 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -4363,7 +4363,7 @@ static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
> ret = PTR_ERR(new_root);
> goto out;
> }
> - if (!is_fstree(new_root->objectid)) {
> + if (!is_fstree(new_root->root_key.objectid)) {
> ret = -ENOENT;
> goto out;
> }
> diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
> index 2ba29f0609d9..16a9771b13fe 100644
> --- a/fs/btrfs/qgroup.c
> +++ b/fs/btrfs/qgroup.c
> @@ -3004,7 +3004,7 @@ int btrfs_qgroup_reserve_data(struct inode *inode,
> int ret;
>
> if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags) ||
> - !is_fstree(root->objectid) || len == 0)
> + !is_fstree(root->root_key.objectid) || len == 0)
> return 0;
>
> /* @reserved parameter is mandatory for qgroup */
> @@ -3090,7 +3090,7 @@ static int qgroup_free_reserved_data(struct inode *inode,
> goto out;
> freed += changeset.bytes_changed;
> }
> - btrfs_qgroup_free_refroot(root->fs_info, root->objectid, freed,
> + btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
> BTRFS_QGROUP_RSV_DATA);
> ret = freed;
> out:
> @@ -3122,7 +3122,7 @@ static int __btrfs_qgroup_release_data(struct inode *inode,
> changeset.bytes_changed, trace_op);
> if (free)
> btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
> - BTRFS_I(inode)->root->objectid,
> + BTRFS_I(inode)->root->root_key.objectid,
> changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
> ret = changeset.bytes_changed;
> out:
> @@ -3215,7 +3215,7 @@ int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
> int ret;
>
> if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
> - !is_fstree(root->objectid) || num_bytes == 0)
> + !is_fstree(root->root_key.objectid) || num_bytes == 0)
> return 0;
>
> BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
> @@ -3240,13 +3240,13 @@ void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
> struct btrfs_fs_info *fs_info = root->fs_info;
>
> if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
> - !is_fstree(root->objectid))
> + !is_fstree(root->root_key.objectid))
> return;
>
> /* TODO: Update trace point to handle such free */
> trace_qgroup_meta_free_all_pertrans(root);
> /* Special value -1 means to free all reserved space */
> - btrfs_qgroup_free_refroot(fs_info, root->objectid, (u64)-1,
> + btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
> BTRFS_QGROUP_RSV_META_PERTRANS);
> }
>
> @@ -3256,7 +3256,7 @@ void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
> struct btrfs_fs_info *fs_info = root->fs_info;
>
> if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
> - !is_fstree(root->objectid))
> + !is_fstree(root->root_key.objectid))
> return;
>
> /*
> @@ -3267,7 +3267,8 @@ void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
> num_bytes = sub_root_meta_rsv(root, num_bytes, type);
> BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
> trace_qgroup_meta_reserve(root, type, -(s64)num_bytes);
> - btrfs_qgroup_free_refroot(fs_info, root->objectid, num_bytes, type);
> + btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
> + num_bytes, type);
> }
>
> static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
> @@ -3321,13 +3322,13 @@ void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
> struct btrfs_fs_info *fs_info = root->fs_info;
>
> if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
> - !is_fstree(root->objectid))
> + !is_fstree(root->root_key.objectid))
> return;
> /* Same as btrfs_qgroup_free_meta_prealloc() */
> num_bytes = sub_root_meta_rsv(root, num_bytes,
> BTRFS_QGROUP_RSV_META_PREALLOC);
> trace_qgroup_meta_convert(root, num_bytes);
> - qgroup_convert_meta(fs_info, root->objectid, num_bytes);
> + qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
> }
>
> /*
> @@ -3354,7 +3355,7 @@ void btrfs_qgroup_check_reserved_leak(struct inode *inode)
> inode->i_ino, unode->val, unode->aux);
> }
> btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
> - BTRFS_I(inode)->root->objectid,
> + BTRFS_I(inode)->root->root_key.objectid,
> changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
>
> }
> diff --git a/fs/btrfs/ref-verify.c b/fs/btrfs/ref-verify.c
> index e5b9e596bb92..d69fbfb30aa9 100644
> --- a/fs/btrfs/ref-verify.c
> +++ b/fs/btrfs/ref-verify.c
> @@ -732,7 +732,7 @@ int btrfs_ref_tree_mod(struct btrfs_root *root, u64 bytenr, u64 num_bytes,
>
> INIT_LIST_HEAD(&ra->list);
> ra->action = action;
> - ra->root = root->objectid;
> + ra->root = root->root_key.objectid;
>
> /*
> * This is an allocation, preallocate the block_entry in case we haven't
> @@ -787,8 +787,8 @@ int btrfs_ref_tree_mod(struct btrfs_root *root, u64 bytenr, u64 num_bytes,
> * one we want to lookup below when we modify the
> * re->num_refs.
> */
> - ref_root = root->objectid;
> - re->root_objectid = root->objectid;
> + ref_root = root->root_key.objectid;
> + re->root_objectid = root->root_key.objectid;
> re->num_refs = 0;
> }
>
> @@ -862,7 +862,7 @@ int btrfs_ref_tree_mod(struct btrfs_root *root, u64 bytenr, u64 num_bytes,
> * didn't thik of some other corner case.
> */
> btrfs_err(fs_info, "failed to find root %llu for %llu",
> - root->objectid, be->bytenr);
> + root->root_key.objectid, be->bytenr);
> dump_block_entry(fs_info, be);
> dump_ref_action(fs_info, ra);
> kfree(ra);
> diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
> index 8783a1776540..d626362687d7 100644
> --- a/fs/btrfs/relocation.c
> +++ b/fs/btrfs/relocation.c
> @@ -884,7 +884,8 @@ struct backref_node *build_backref_tree(struct reloc_control *rc,
> cur->bytenr) {
> btrfs_err(root->fs_info,
> "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)",
> - cur->bytenr, level - 1, root->objectid,
> + cur->bytenr, level - 1,
> + root->root_key.objectid,
> node_key->objectid, node_key->type,
> node_key->offset);
> err = -ENOENT;
> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
> index 551294a6c9e2..f003ec949726 100644
> --- a/fs/btrfs/send.c
> +++ b/fs/btrfs/send.c
> @@ -1186,9 +1186,9 @@ static int __clone_root_cmp_bsearch(const void *key, const void *elt)
> u64 root = (u64)(uintptr_t)key;
> struct clone_root *cr = (struct clone_root *)elt;
>
> - if (root < cr->root->objectid)
> + if (root < cr->root->root_key.objectid)
> return -1;
> - if (root > cr->root->objectid)
> + if (root > cr->root->root_key.objectid)
> return 1;
> return 0;
> }
> @@ -1198,9 +1198,9 @@ static int __clone_root_cmp_sort(const void *e1, const void *e2)
> struct clone_root *cr1 = (struct clone_root *)e1;
> struct clone_root *cr2 = (struct clone_root *)e2;
>
> - if (cr1->root->objectid < cr2->root->objectid)
> + if (cr1->root->root_key.objectid < cr2->root->root_key.objectid)
> return -1;
> - if (cr1->root->objectid > cr2->root->objectid)
> + if (cr1->root->root_key.objectid > cr2->root->root_key.objectid)
> return 1;
> return 0;
> }
> @@ -2346,7 +2346,7 @@ static int send_subvol_begin(struct send_ctx *sctx)
> return -ENOMEM;
> }
>
> - key.objectid = send_root->objectid;
> + key.objectid = send_root->root_key.objectid;
> key.type = BTRFS_ROOT_BACKREF_KEY;
> key.offset = 0;
>
> @@ -2362,7 +2362,7 @@ static int send_subvol_begin(struct send_ctx *sctx)
> leaf = path->nodes[0];
> btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
> if (key.type != BTRFS_ROOT_BACKREF_KEY ||
> - key.objectid != send_root->objectid) {
> + key.objectid != send_root->root_key.objectid) {
> ret = -ENOENT;
> goto out;
> }
> @@ -4907,8 +4907,8 @@ static int send_clone(struct send_ctx *sctx,
>
> btrfs_debug(sctx->send_root->fs_info,
> "send_clone offset=%llu, len=%d, clone_root=%llu, clone_inode=%llu, clone_offset=%llu",
> - offset, len, clone_root->root->objectid, clone_root->ino,
> - clone_root->offset);
> + offset, len, clone_root->root->root_key.objectid,
> + clone_root->ino, clone_root->offset);
>
> p = fs_path_alloc();
> if (!p)
> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index 67de3c0fc85b..f114e848f4c9 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -2177,8 +2177,10 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
> buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
> buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
> /* Mask in the root object ID too, to disambiguate subvols */
> - buf->f_fsid.val[0] ^= BTRFS_I(d_inode(dentry))->root->objectid >> 32;
> - buf->f_fsid.val[1] ^= BTRFS_I(d_inode(dentry))->root->objectid;
> + buf->f_fsid.val[0] ^=
> + BTRFS_I(d_inode(dentry))->root->root_key.objectid >> 32;
> + buf->f_fsid.val[1] ^=
> + BTRFS_I(d_inode(dentry))->root->root_key.objectid;
>
> return 0;
> }
> diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
> index 3b84f5015029..c429bdda6348 100644
> --- a/fs/btrfs/transaction.c
> +++ b/fs/btrfs/transaction.c
> @@ -118,7 +118,7 @@ static noinline void switch_commit_roots(struct btrfs_transaction *trans)
> list_del_init(&root->dirty_list);
> free_extent_buffer(root->commit_root);
> root->commit_root = btrfs_root_node(root);
> - if (is_fstree(root->objectid))
> + if (is_fstree(root->root_key.objectid))
> btrfs_unpin_free_ino(root);
> clear_btree_io_tree(&root->dirty_log_pages);
> }
> @@ -2330,7 +2330,7 @@ int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root)
> list_del_init(&root->root_list);
> spin_unlock(&fs_info->trans_lock);
>
> - btrfs_debug(fs_info, "cleaner removing %llu", root->objectid);
> + btrfs_debug(fs_info, "cleaner removing %llu", root->root_key.objectid);
>
> btrfs_kill_all_delayed_nodes(root);
>
> diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
> index b401c4e36394..abe3ff774f58 100644
> --- a/include/trace/events/btrfs.h
> +++ b/include/trace/events/btrfs.h
> @@ -316,7 +316,7 @@ DECLARE_EVENT_CLASS(btrfs__file_extent_item_regular,
> ),
>
> TP_fast_assign_btrfs(bi->root->fs_info,
> - __entry->root_obj = bi->root->objectid;
> + __entry->root_obj = bi->root->root_key.objectid;
> __entry->ino = btrfs_ino(bi);
> __entry->isize = bi->vfs_inode.i_size;
> __entry->disk_isize = bi->disk_i_size;
> @@ -367,7 +367,7 @@ DECLARE_EVENT_CLASS(
>
> TP_fast_assign_btrfs(
> bi->root->fs_info,
> - __entry->root_obj = bi->root->objectid;
> + __entry->root_obj = bi->root->root_key.objectid;
> __entry->ino = btrfs_ino(bi);
> __entry->isize = bi->vfs_inode.i_size;
> __entry->disk_isize = bi->disk_i_size;
> @@ -1477,7 +1477,8 @@ DECLARE_EVENT_CLASS(btrfs__qgroup_rsv_data,
> ),
>
> TP_fast_assign_btrfs(btrfs_sb(inode->i_sb),
> - __entry->rootid = BTRFS_I(inode)->root->objectid;
> + __entry->rootid =
> + BTRFS_I(inode)->root->root_key.objectid;
> __entry->ino = btrfs_ino(BTRFS_I(inode));
> __entry->start = start;
> __entry->len = len;
> @@ -1675,7 +1676,7 @@ TRACE_EVENT(qgroup_meta_reserve,
> ),
>
> TP_fast_assign_btrfs(root->fs_info,
> - __entry->refroot = root->objectid;
> + __entry->refroot = root->root_key.objectid;
> __entry->diff = diff;
> ),
>
> @@ -1697,7 +1698,7 @@ TRACE_EVENT(qgroup_meta_convert,
> ),
>
> TP_fast_assign_btrfs(root->fs_info,
> - __entry->refroot = root->objectid;
> + __entry->refroot = root->root_key.objectid;
> __entry->diff = diff;
> ),
>
> @@ -1721,7 +1722,7 @@ TRACE_EVENT(qgroup_meta_free_all_pertrans,
> ),
>
> TP_fast_assign_btrfs(root->fs_info,
> - __entry->refroot = root->objectid;
> + __entry->refroot = root->root_key.objectid;
> spin_lock(&root->qgroup_meta_rsv_lock);
> __entry->diff = -(s64)root->qgroup_meta_rsv_pertrans;
> spin_unlock(&root->qgroup_meta_rsv_lock);
> @@ -1802,7 +1803,7 @@ TRACE_EVENT(btrfs_inode_mod_outstanding_extents,
> ),
>
> TP_fast_assign_btrfs(root->fs_info,
> - __entry->root_objectid = root->objectid;
> + __entry->root_objectid = root->root_key.objectid;
> __entry->ino = ino;
> __entry->mod = mod;
> ),
>
Attachment:
signature.asc
Description: OpenPGP digital signature
