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-rw-r--r--fs/nilfs2/btnode.c23
-rw-r--r--fs/nilfs2/btnode.h1
-rw-r--r--fs/nilfs2/btree.c27
-rw-r--r--fs/nilfs2/gcinode.c7
-rw-r--r--fs/nilfs2/inode.c104
-rw-r--r--fs/nilfs2/mdt.c7
-rw-r--r--fs/nilfs2/nilfs.h14
-rw-r--r--fs/nilfs2/page.c7
-rw-r--r--fs/nilfs2/segment.c9
-rw-r--r--fs/nilfs2/super.c5
10 files changed, 154 insertions, 50 deletions
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 66bdaa2cf496..ca611ac09f7c 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -20,6 +20,23 @@
#include "page.h"
#include "btnode.h"
+
+/**
+ * nilfs_init_btnc_inode - initialize B-tree node cache inode
+ * @btnc_inode: inode to be initialized
+ *
+ * nilfs_init_btnc_inode() sets up an inode for B-tree node cache.
+ */
+void nilfs_init_btnc_inode(struct inode *btnc_inode)
+{
+ struct nilfs_inode_info *ii = NILFS_I(btnc_inode);
+
+ btnc_inode->i_mode = S_IFREG;
+ ii->i_flags = 0;
+ memset(&ii->i_bmap_data, 0, sizeof(struct nilfs_bmap));
+ mapping_set_gfp_mask(btnc_inode->i_mapping, GFP_NOFS);
+}
+
void nilfs_btnode_cache_clear(struct address_space *btnc)
{
invalidate_mapping_pages(btnc, 0, -1);
@@ -29,7 +46,7 @@ void nilfs_btnode_cache_clear(struct address_space *btnc)
struct buffer_head *
nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr)
{
- struct inode *inode = NILFS_BTNC_I(btnc);
+ struct inode *inode = btnc->host;
struct buffer_head *bh;
bh = nilfs_grab_buffer(inode, btnc, blocknr, BIT(BH_NILFS_Node));
@@ -57,7 +74,7 @@ int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr,
struct buffer_head **pbh, sector_t *submit_ptr)
{
struct buffer_head *bh;
- struct inode *inode = NILFS_BTNC_I(btnc);
+ struct inode *inode = btnc->host;
struct page *page;
int err;
@@ -157,7 +174,7 @@ int nilfs_btnode_prepare_change_key(struct address_space *btnc,
struct nilfs_btnode_chkey_ctxt *ctxt)
{
struct buffer_head *obh, *nbh;
- struct inode *inode = NILFS_BTNC_I(btnc);
+ struct inode *inode = btnc->host;
__u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey;
int err;
diff --git a/fs/nilfs2/btnode.h b/fs/nilfs2/btnode.h
index 11663650add7..bd5544e63a01 100644
--- a/fs/nilfs2/btnode.h
+++ b/fs/nilfs2/btnode.h
@@ -30,6 +30,7 @@ struct nilfs_btnode_chkey_ctxt {
struct buffer_head *newbh;
};
+void nilfs_init_btnc_inode(struct inode *btnc_inode);
void nilfs_btnode_cache_clear(struct address_space *);
struct buffer_head *nilfs_btnode_create_block(struct address_space *btnc,
__u64 blocknr);
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c
index 3594eabe1419..f544c22fff78 100644
--- a/fs/nilfs2/btree.c
+++ b/fs/nilfs2/btree.c
@@ -58,7 +58,8 @@ static void nilfs_btree_free_path(struct nilfs_btree_path *path)
static int nilfs_btree_get_new_block(const struct nilfs_bmap *btree,
__u64 ptr, struct buffer_head **bhp)
{
- struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct inode *btnc_inode = NILFS_BMAP_I(btree)->i_assoc_inode;
+ struct address_space *btnc = btnc_inode->i_mapping;
struct buffer_head *bh;
bh = nilfs_btnode_create_block(btnc, ptr);
@@ -470,7 +471,8 @@ static int __nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
struct buffer_head **bhp,
const struct nilfs_btree_readahead_info *ra)
{
- struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct inode *btnc_inode = NILFS_BMAP_I(btree)->i_assoc_inode;
+ struct address_space *btnc = btnc_inode->i_mapping;
struct buffer_head *bh, *ra_bh;
sector_t submit_ptr = 0;
int ret;
@@ -1741,6 +1743,10 @@ nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *btree, __u64 key,
dat = nilfs_bmap_get_dat(btree);
}
+ ret = nilfs_attach_btree_node_cache(&NILFS_BMAP_I(btree)->vfs_inode);
+ if (ret < 0)
+ return ret;
+
ret = nilfs_bmap_prepare_alloc_ptr(btree, dreq, dat);
if (ret < 0)
return ret;
@@ -1913,7 +1919,7 @@ static int nilfs_btree_prepare_update_v(struct nilfs_bmap *btree,
path[level].bp_ctxt.newkey = path[level].bp_newreq.bpr_ptr;
path[level].bp_ctxt.bh = path[level].bp_bh;
ret = nilfs_btnode_prepare_change_key(
- &NILFS_BMAP_I(btree)->i_btnode_cache,
+ NILFS_BMAP_I(btree)->i_assoc_inode->i_mapping,
&path[level].bp_ctxt);
if (ret < 0) {
nilfs_dat_abort_update(dat,
@@ -1939,7 +1945,7 @@ static void nilfs_btree_commit_update_v(struct nilfs_bmap *btree,
if (buffer_nilfs_node(path[level].bp_bh)) {
nilfs_btnode_commit_change_key(
- &NILFS_BMAP_I(btree)->i_btnode_cache,
+ NILFS_BMAP_I(btree)->i_assoc_inode->i_mapping,
&path[level].bp_ctxt);
path[level].bp_bh = path[level].bp_ctxt.bh;
}
@@ -1958,7 +1964,7 @@ static void nilfs_btree_abort_update_v(struct nilfs_bmap *btree,
&path[level].bp_newreq.bpr_req);
if (buffer_nilfs_node(path[level].bp_bh))
nilfs_btnode_abort_change_key(
- &NILFS_BMAP_I(btree)->i_btnode_cache,
+ NILFS_BMAP_I(btree)->i_assoc_inode->i_mapping,
&path[level].bp_ctxt);
}
@@ -2134,7 +2140,8 @@ static void nilfs_btree_add_dirty_buffer(struct nilfs_bmap *btree,
static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *btree,
struct list_head *listp)
{
- struct address_space *btcache = &NILFS_BMAP_I(btree)->i_btnode_cache;
+ struct inode *btnc_inode = NILFS_BMAP_I(btree)->i_assoc_inode;
+ struct address_space *btcache = btnc_inode->i_mapping;
struct list_head lists[NILFS_BTREE_LEVEL_MAX];
struct pagevec pvec;
struct buffer_head *bh, *head;
@@ -2188,12 +2195,12 @@ static int nilfs_btree_assign_p(struct nilfs_bmap *btree,
path[level].bp_ctxt.newkey = blocknr;
path[level].bp_ctxt.bh = *bh;
ret = nilfs_btnode_prepare_change_key(
- &NILFS_BMAP_I(btree)->i_btnode_cache,
+ NILFS_BMAP_I(btree)->i_assoc_inode->i_mapping,
&path[level].bp_ctxt);
if (ret < 0)
return ret;
nilfs_btnode_commit_change_key(
- &NILFS_BMAP_I(btree)->i_btnode_cache,
+ NILFS_BMAP_I(btree)->i_assoc_inode->i_mapping,
&path[level].bp_ctxt);
*bh = path[level].bp_ctxt.bh;
}
@@ -2398,6 +2405,10 @@ int nilfs_btree_init(struct nilfs_bmap *bmap)
if (nilfs_btree_root_broken(nilfs_btree_get_root(bmap), bmap->b_inode))
ret = -EIO;
+ else
+ ret = nilfs_attach_btree_node_cache(
+ &NILFS_BMAP_I(bmap)->vfs_inode);
+
return ret;
}
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index a8f5315f01e3..04fdd420eae7 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -126,9 +126,10 @@ int nilfs_gccache_submit_read_data(struct inode *inode, sector_t blkoff,
int nilfs_gccache_submit_read_node(struct inode *inode, sector_t pbn,
__u64 vbn, struct buffer_head **out_bh)
{
+ struct inode *btnc_inode = NILFS_I(inode)->i_assoc_inode;
int ret;
- ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache,
+ ret = nilfs_btnode_submit_block(btnc_inode->i_mapping,
vbn ? : pbn, pbn, REQ_OP_READ, 0,
out_bh, &pbn);
if (ret == -EEXIST) /* internal code (cache hit) */
@@ -170,7 +171,7 @@ int nilfs_init_gcinode(struct inode *inode)
ii->i_flags = 0;
nilfs_bmap_init_gc(ii->i_bmap);
- return 0;
+ return nilfs_attach_btree_node_cache(inode);
}
/**
@@ -185,7 +186,7 @@ void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs)
ii = list_first_entry(head, struct nilfs_inode_info, i_dirty);
list_del_init(&ii->i_dirty);
truncate_inode_pages(&ii->vfs_inode.i_data, 0);
- nilfs_btnode_cache_clear(&ii->i_btnode_cache);
+ nilfs_btnode_cache_clear(ii->i_assoc_inode->i_mapping);
iput(&ii->vfs_inode);
}
}
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 476a4a649f38..2557f5f5a935 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -29,12 +29,14 @@
* @cno: checkpoint number
* @root: pointer on NILFS root object (mounted checkpoint)
* @for_gc: inode for GC flag
+ * @for_btnc: inode for B-tree node cache flag
*/
struct nilfs_iget_args {
u64 ino;
__u64 cno;
struct nilfs_root *root;
- int for_gc;
+ bool for_gc;
+ bool for_btnc;
};
static int nilfs_iget_test(struct inode *inode, void *opaque);
@@ -312,7 +314,8 @@ static int nilfs_insert_inode_locked(struct inode *inode,
unsigned long ino)
{
struct nilfs_iget_args args = {
- .ino = ino, .root = root, .cno = 0, .for_gc = 0
+ .ino = ino, .root = root, .cno = 0, .for_gc = false,
+ .for_btnc = false
};
return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
@@ -525,6 +528,13 @@ static int nilfs_iget_test(struct inode *inode, void *opaque)
return 0;
ii = NILFS_I(inode);
+ if (test_bit(NILFS_I_BTNC, &ii->i_state)) {
+ if (!args->for_btnc)
+ return 0;
+ } else if (args->for_btnc) {
+ return 0;
+ }
+
if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
return !args->for_gc;
@@ -536,15 +546,15 @@ static int nilfs_iget_set(struct inode *inode, void *opaque)
struct nilfs_iget_args *args = opaque;
inode->i_ino = args->ino;
- if (args->for_gc) {
+ NILFS_I(inode)->i_cno = args->cno;
+ NILFS_I(inode)->i_root = args->root;
+ if (args->root && args->ino == NILFS_ROOT_INO)
+ nilfs_get_root(args->root);
+
+ if (args->for_gc)
NILFS_I(inode)->i_state = BIT(NILFS_I_GCINODE);
- NILFS_I(inode)->i_cno = args->cno;
- NILFS_I(inode)->i_root = NULL;
- } else {
- if (args->root && args->ino == NILFS_ROOT_INO)
- nilfs_get_root(args->root);
- NILFS_I(inode)->i_root = args->root;
- }
+ if (args->for_btnc)
+ NILFS_I(inode)->i_state |= BIT(NILFS_I_BTNC);
return 0;
}
@@ -552,7 +562,8 @@ struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
unsigned long ino)
{
struct nilfs_iget_args args = {
- .ino = ino, .root = root, .cno = 0, .for_gc = 0
+ .ino = ino, .root = root, .cno = 0, .for_gc = false,
+ .for_btnc = false
};
return ilookup5(sb, ino, nilfs_iget_test, &args);
@@ -562,7 +573,8 @@ struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
unsigned long ino)
{
struct nilfs_iget_args args = {
- .ino = ino, .root = root, .cno = 0, .for_gc = 0
+ .ino = ino, .root = root, .cno = 0, .for_gc = false,
+ .for_btnc = false
};
return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
@@ -593,7 +605,8 @@ struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
__u64 cno)
{
struct nilfs_iget_args args = {
- .ino = ino, .root = NULL, .cno = cno, .for_gc = 1
+ .ino = ino, .root = NULL, .cno = cno, .for_gc = true,
+ .for_btnc = false
};
struct inode *inode;
int err;
@@ -613,6 +626,68 @@ struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
return inode;
}
+/**
+ * nilfs_attach_btree_node_cache - attach a B-tree node cache to the inode
+ * @inode: inode object
+ *
+ * nilfs_attach_btree_node_cache() attaches a B-tree node cache to @inode,
+ * or does nothing if the inode already has it. This function allocates
+ * an additional inode to maintain page cache of B-tree nodes one-on-one.
+ *
+ * Return Value: On success, 0 is returned. On errors, one of the following
+ * negative error code is returned.
+ *
+ * %-ENOMEM - Insufficient memory available.
+ */
+int nilfs_attach_btree_node_cache(struct inode *inode)
+{
+ struct nilfs_inode_info *ii = NILFS_I(inode);
+ struct inode *btnc_inode;
+ struct nilfs_iget_args args;
+
+ if (ii->i_assoc_inode)
+ return 0;
+
+ args.ino = inode->i_ino;
+ args.root = ii->i_root;
+ args.cno = ii->i_cno;
+ args.for_gc = test_bit(NILFS_I_GCINODE, &ii->i_state) != 0;
+ args.for_btnc = true;
+
+ btnc_inode = iget5_locked(inode->i_sb, inode->i_ino, nilfs_iget_test,
+ nilfs_iget_set, &args);
+ if (unlikely(!btnc_inode))
+ return -ENOMEM;
+ if (btnc_inode->i_state & I_NEW) {
+ nilfs_init_btnc_inode(btnc_inode);
+ unlock_new_inode(btnc_inode);
+ }
+ NILFS_I(btnc_inode)->i_assoc_inode = inode;
+ NILFS_I(btnc_inode)->i_bmap = ii->i_bmap;
+ ii->i_assoc_inode = btnc_inode;
+
+ return 0;
+}
+
+/**
+ * nilfs_detach_btree_node_cache - detach the B-tree node cache from the inode
+ * @inode: inode object
+ *
+ * nilfs_detach_btree_node_cache() detaches the B-tree node cache and its
+ * holder inode bound to @inode, or does nothing if @inode doesn't have it.
+ */
+void nilfs_detach_btree_node_cache(struct inode *inode)
+{
+ struct nilfs_inode_info *ii = NILFS_I(inode);
+ struct inode *btnc_inode = ii->i_assoc_inode;
+
+ if (btnc_inode) {
+ NILFS_I(btnc_inode)->i_assoc_inode = NULL;
+ ii->i_assoc_inode = NULL;
+ iput(btnc_inode);
+ }
+}
+
void nilfs_write_inode_common(struct inode *inode,
struct nilfs_inode *raw_inode, int has_bmap)
{
@@ -760,7 +835,8 @@ static void nilfs_clear_inode(struct inode *inode)
if (test_bit(NILFS_I_BMAP, &ii->i_state))
nilfs_bmap_clear(ii->i_bmap);
- nilfs_btnode_cache_clear(&ii->i_btnode_cache);
+ if (!test_bit(NILFS_I_BTNC, &ii->i_state))
+ nilfs_detach_btree_node_cache(inode);
if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
nilfs_put_root(ii->i_root);
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 78db33decd72..a8274d0efa37 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -533,7 +533,7 @@ int nilfs_mdt_save_to_shadow_map(struct inode *inode)
goto out;
ret = nilfs_copy_dirty_pages(&shadow->frozen_btnodes,
- &ii->i_btnode_cache);
+ ii->i_assoc_inode->i_mapping);
if (ret)
goto out;
@@ -624,8 +624,9 @@ void nilfs_mdt_restore_from_shadow_map(struct inode *inode)
nilfs_clear_dirty_pages(inode->i_mapping, true);
nilfs_copy_back_pages(inode->i_mapping, &shadow->frozen_data);
- nilfs_clear_dirty_pages(&ii->i_btnode_cache, true);
- nilfs_copy_back_pages(&ii->i_btnode_cache, &shadow->frozen_btnodes);
+ nilfs_clear_dirty_pages(ii->i_assoc_inode->i_mapping, true);
+ nilfs_copy_back_pages(ii->i_assoc_inode->i_mapping,
+ &shadow->frozen_btnodes);
nilfs_bmap_restore(ii->i_bmap, &shadow->bmap_store);
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index a7b81755c350..36b048db00b7 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -28,7 +28,7 @@
* @i_xattr: <TODO>
* @i_dir_start_lookup: page index of last successful search
* @i_cno: checkpoint number for GC inode
- * @i_btnode_cache: cached pages of b-tree nodes
+ * @i_assoc_inode: associated inode (B-tree node cache holder or back pointer)
* @i_dirty: list for connecting dirty files
* @xattr_sem: semaphore for extended attributes processing
* @i_bh: buffer contains disk inode
@@ -43,7 +43,7 @@ struct nilfs_inode_info {
__u64 i_xattr; /* sector_t ??? */
__u32 i_dir_start_lookup;
__u64 i_cno; /* check point number for GC inode */
- struct address_space i_btnode_cache;
+ struct inode *i_assoc_inode;
struct list_head i_dirty; /* List for connecting dirty files */
#ifdef CONFIG_NILFS_XATTR
@@ -75,13 +75,6 @@ NILFS_BMAP_I(const struct nilfs_bmap *bmap)
return container_of(bmap, struct nilfs_inode_info, i_bmap_data);
}
-static inline struct inode *NILFS_BTNC_I(struct address_space *btnc)
-{
- struct nilfs_inode_info *ii =
- container_of(btnc, struct nilfs_inode_info, i_btnode_cache);
- return &ii->vfs_inode;
-}
-
/*
* Dynamic state flags of NILFS on-memory inode (i_state)
*/
@@ -98,6 +91,7 @@ enum {
NILFS_I_INODE_SYNC, /* dsync is not allowed for inode */
NILFS_I_BMAP, /* has bmap and btnode_cache */
NILFS_I_GCINODE, /* inode for GC, on memory only */
+ NILFS_I_BTNC, /* inode for btree node cache */
};
/*
@@ -267,6 +261,8 @@ struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
unsigned long ino);
extern struct inode *nilfs_iget_for_gc(struct super_block *sb,
unsigned long ino, __u64 cno);
+int nilfs_attach_btree_node_cache(struct inode *inode);
+void nilfs_detach_btree_node_cache(struct inode *inode);
extern void nilfs_update_inode(struct inode *, struct buffer_head *, int);
extern void nilfs_truncate(struct inode *);
extern void nilfs_evict_inode(struct inode *);
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 063dd16d75b5..45e079295008 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -448,10 +448,9 @@ void nilfs_mapping_init(struct address_space *mapping, struct inode *inode)
/*
* NILFS2 needs clear_page_dirty() in the following two cases:
*
- * 1) For B-tree node pages and data pages of the dat/gcdat, NILFS2 clears
- * page dirty flags when it copies back pages from the shadow cache
- * (gcdat->{i_mapping,i_btnode_cache}) to its original cache
- * (dat->{i_mapping,i_btnode_cache}).
+ * 1) For B-tree node pages and data pages of DAT file, NILFS2 clears dirty
+ * flag of pages when it copies back pages from shadow cache to the
+ * original cache.
*
* 2) Some B-tree operations like insertion or deletion may dispose buffers
* in dirty state, and this needs to cancel the dirty state of their pages.
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 85a853334771..0afe0832c754 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -733,15 +733,18 @@ static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
struct list_head *listp)
{
struct nilfs_inode_info *ii = NILFS_I(inode);
- struct address_space *mapping = &ii->i_btnode_cache;
+ struct inode *btnc_inode = ii->i_assoc_inode;
struct pagevec pvec;
struct buffer_head *bh, *head;
unsigned int i;
pgoff_t index = 0;
+ if (!btnc_inode)
+ return;
+
pagevec_init(&pvec);
- while (pagevec_lookup_tag(&pvec, mapping, &index,
+ while (pagevec_lookup_tag(&pvec, btnc_inode->i_mapping, &index,
PAGECACHE_TAG_DIRTY)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
bh = head = page_buffers(pvec.pages[i]);
@@ -2410,7 +2413,7 @@ nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
continue;
list_del_init(&ii->i_dirty);
truncate_inode_pages(&ii->vfs_inode.i_data, 0);
- nilfs_btnode_cache_clear(&ii->i_btnode_cache);
+ nilfs_btnode_cache_clear(ii->i_assoc_inode->i_mapping);
iput(&ii->vfs_inode);
}
}
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 3e05c98631ec..ba108f915391 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -157,7 +157,8 @@ struct inode *nilfs_alloc_inode(struct super_block *sb)
ii->i_bh = NULL;
ii->i_state = 0;
ii->i_cno = 0;
- nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode);
+ ii->i_assoc_inode = NULL;
+ ii->i_bmap = &ii->i_bmap_data;
return &ii->vfs_inode;
}
@@ -1377,8 +1378,6 @@ static void nilfs_inode_init_once(void *obj)
#ifdef CONFIG_NILFS_XATTR
init_rwsem(&ii->xattr_sem);
#endif
- address_space_init_once(&ii->i_btnode_cache);
- ii->i_bmap = &ii->i_bmap_data;
inode_init_once(&ii->vfs_inode);
}
generated by cgit (git 2.34.1) at 2024-06-20 18:22:56 +0000