[PATCH 2/3] f2fs: fix conditions to remain recovery information in f2fs_sync_file

From: Jaegeuk Kim
Date: Thu Sep 18 2014 - 01:51:21 EST


This patch revisited whole the recovery information during the f2fs_sync_file.

In this patch, there are three information to make a decision.

a) IS_CHECKPOINTED, /* is it checkpointed before? */
b) HAS_FSYNCED_INODE, /* is the inode fsynced before? */
c) HAS_LAST_FSYNC, /* has the latest node fsync mark? */

And, the scenarios for our rule are based on:

[Term] F: fsync_mark, D: dentry_mark

1. inode(x) | CP | inode(x) | dnode(F)
2. inode(x) | CP | inode(F) | dnode(F)
3. inode(x) | CP | dnode(F) | inode(x) | inode(F)
4. inode(x) | CP | dnode(F) | inode(F)
5. CP | inode(x) | dnode(F) | inode(DF)
6. CP | inode(DF) | dnode(F)
7. CP | dnode(F) | inode(DF)
8. CP | dnode(F) | inode(x) | inode(DF)

For example, #3, the three conditions should be changed as follows.

inode(x) | CP | dnode(F) | inode(x) | inode(F)
a) x o o o o
b) x x x x o
c) x o o x o

If f2fs_sync_file stops ------^,
it should write inode(F) --------------^

So, the need_inode_block_update should return true, since
c) get_nat_flag(e, HAS_LAST_FSYNC), is false.

For example, #8,
CP | alloc | dnode(F) | inode(x) | inode(DF)
a) o x x x x
b) x x x o
c) o o x o

If f2fs_sync_file stops -------^,
it should write inode(DF) --------------^

Note that, the roll-forward policy should follow this rule, which means,
if there are any missing blocks, we doesn't need to recover that inode.

Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/data.c | 3 ---
fs/f2fs/f2fs.h | 6 +++---
fs/f2fs/file.c | 10 ++++++----
fs/f2fs/node.c | 56 +++++++++++++++++++++++++++++++++++---------------------
fs/f2fs/node.h | 21 ++++++++++++---------
5 files changed, 56 insertions(+), 40 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 0e37658..fdc3dbe 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1089,9 +1089,6 @@ static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
if (check_direct_IO(inode, rw, iter, offset))
return 0;

- /* clear fsync mark to recover these blocks */
- fsync_mark_clear(F2FS_I_SB(inode), inode->i_ino);
-
trace_f2fs_direct_IO_enter(inode, offset, count, rw);

err = blockdev_direct_IO(rw, iocb, inode, iter, offset, get_data_block);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9fc1bcd..fd44083 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1224,9 +1224,9 @@ struct dnode_of_data;
struct node_info;

bool available_free_memory(struct f2fs_sb_info *, int);
-int is_checkpointed_node(struct f2fs_sb_info *, nid_t);
-bool fsync_mark_done(struct f2fs_sb_info *, nid_t);
-void fsync_mark_clear(struct f2fs_sb_info *, nid_t);
+bool is_checkpointed_node(struct f2fs_sb_info *, nid_t);
+bool has_fsynced_inode(struct f2fs_sb_info *, nid_t);
+bool need_inode_block_update(struct f2fs_sb_info *, nid_t);
void get_node_info(struct f2fs_sb_info *, nid_t, struct node_info *);
int get_dnode_of_data(struct dnode_of_data *, pgoff_t, int);
int truncate_inode_blocks(struct inode *, pgoff_t);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index af06e22..3035c79 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -207,15 +207,17 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
up_write(&fi->i_sem);
}
} else {
- /* if there is no written node page, write its inode page */
- while (!sync_node_pages(sbi, ino, &wbc)) {
- if (fsync_mark_done(sbi, ino))
- goto out;
+sync_nodes:
+ sync_node_pages(sbi, ino, &wbc);
+
+ if (need_inode_block_update(sbi, ino)) {
mark_inode_dirty_sync(inode);
ret = f2fs_write_inode(inode, NULL);
if (ret)
goto out;
+ goto sync_nodes;
}
+
ret = wait_on_node_pages_writeback(sbi, ino);
if (ret)
goto out;
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index d19d6b1..7a2d9c9 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -123,44 +123,48 @@ static void __del_from_nat_cache(struct f2fs_nm_info *nm_i, struct nat_entry *e)
kmem_cache_free(nat_entry_slab, e);
}

-int is_checkpointed_node(struct f2fs_sb_info *sbi, nid_t nid)
+bool is_checkpointed_node(struct f2fs_sb_info *sbi, nid_t nid)
{
struct f2fs_nm_info *nm_i = NM_I(sbi);
struct nat_entry *e;
- int is_cp = 1;
+ bool is_cp = true;

read_lock(&nm_i->nat_tree_lock);
e = __lookup_nat_cache(nm_i, nid);
if (e && !get_nat_flag(e, IS_CHECKPOINTED))
- is_cp = 0;
+ is_cp = false;
read_unlock(&nm_i->nat_tree_lock);
return is_cp;
}

-bool fsync_mark_done(struct f2fs_sb_info *sbi, nid_t nid)
+bool has_fsynced_inode(struct f2fs_sb_info *sbi, nid_t ino)
{
struct f2fs_nm_info *nm_i = NM_I(sbi);
struct nat_entry *e;
- bool fsync_done = false;
+ bool fsynced = false;

read_lock(&nm_i->nat_tree_lock);
- e = __lookup_nat_cache(nm_i, nid);
- if (e)
- fsync_done = get_nat_flag(e, HAS_FSYNC_MARK);
+ e = __lookup_nat_cache(nm_i, ino);
+ if (e && get_nat_flag(e, HAS_FSYNCED_INODE))
+ fsynced = true;
read_unlock(&nm_i->nat_tree_lock);
- return fsync_done;
+ return fsynced;
}

-void fsync_mark_clear(struct f2fs_sb_info *sbi, nid_t nid)
+bool need_inode_block_update(struct f2fs_sb_info *sbi, nid_t ino)
{
struct f2fs_nm_info *nm_i = NM_I(sbi);
struct nat_entry *e;
+ bool need_update = true;

- write_lock(&nm_i->nat_tree_lock);
- e = __lookup_nat_cache(nm_i, nid);
- if (e)
- set_nat_flag(e, HAS_FSYNC_MARK, false);
- write_unlock(&nm_i->nat_tree_lock);
+ read_lock(&nm_i->nat_tree_lock);
+ e = __lookup_nat_cache(nm_i, ino);
+ if (e && get_nat_flag(e, HAS_LAST_FSYNC) &&
+ (get_nat_flag(e, IS_CHECKPOINTED) ||
+ get_nat_flag(e, HAS_FSYNCED_INODE)))
+ need_update = false;
+ read_unlock(&nm_i->nat_tree_lock);
+ return need_update;
}

static struct nat_entry *grab_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid)
@@ -176,7 +180,7 @@ static struct nat_entry *grab_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid)
}
memset(new, 0, sizeof(struct nat_entry));
nat_set_nid(new, nid);
- set_nat_flag(new, IS_CHECKPOINTED, true);
+ nat_reset_flag(new);
list_add_tail(&new->list, &nm_i->nat_entries);
nm_i->nat_cnt++;
return new;
@@ -244,12 +248,17 @@ retry:

/* change address */
nat_set_blkaddr(e, new_blkaddr);
+ if (new_blkaddr == NEW_ADDR || new_blkaddr == NULL_ADDR)
+ set_nat_flag(e, IS_CHECKPOINTED, false);
__set_nat_cache_dirty(nm_i, e);

/* update fsync_mark if its inode nat entry is still alive */
e = __lookup_nat_cache(nm_i, ni->ino);
- if (e)
- set_nat_flag(e, HAS_FSYNC_MARK, fsync_done);
+ if (e) {
+ if (fsync_done && ni->nid == ni->ino)
+ set_nat_flag(e, HAS_FSYNCED_INODE, true);
+ set_nat_flag(e, HAS_LAST_FSYNC, fsync_done);
+ }
write_unlock(&nm_i->nat_tree_lock);
}

@@ -1121,10 +1130,14 @@ continue_unlock:

/* called by fsync() */
if (ino && IS_DNODE(page)) {
- int mark = !is_checkpointed_node(sbi, ino);
set_fsync_mark(page, 1);
- if (IS_INODE(page))
- set_dentry_mark(page, mark);
+ if (IS_INODE(page)) {
+ if (!is_checkpointed_node(sbi, ino) &&
+ !has_fsynced_inode(sbi, ino))
+ set_dentry_mark(page, 1);
+ else
+ set_dentry_mark(page, 0);
+ }
nwritten++;
} else {
set_fsync_mark(page, 0);
@@ -1912,6 +1925,7 @@ void flush_nat_entries(struct f2fs_sb_info *sbi)
write_unlock(&nm_i->nat_tree_lock);
} else {
write_lock(&nm_i->nat_tree_lock);
+ nat_reset_flag(ne);
__clear_nat_cache_dirty(nm_i, ne);
write_unlock(&nm_i->nat_tree_lock);
}
diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
index 3043778..b8ba63c 100644
--- a/fs/f2fs/node.h
+++ b/fs/f2fs/node.h
@@ -41,7 +41,8 @@ struct node_info {

enum {
IS_CHECKPOINTED, /* is it checkpointed before? */
- HAS_FSYNC_MARK, /* has the latest node fsync mark? */
+ HAS_FSYNCED_INODE, /* is the inode fsynced before? */
+ HAS_LAST_FSYNC, /* has the latest node fsync mark? */
};

struct nat_entry {
@@ -60,15 +61,9 @@ struct nat_entry {
#define nat_set_version(nat, v) (nat->ni.version = v)

#define __set_nat_cache_dirty(nm_i, ne) \
- do { \
- set_nat_flag(ne, IS_CHECKPOINTED, false); \
- list_move_tail(&ne->list, &nm_i->dirty_nat_entries); \
- } while (0)
+ list_move_tail(&ne->list, &nm_i->dirty_nat_entries);
#define __clear_nat_cache_dirty(nm_i, ne) \
- do { \
- set_nat_flag(ne, IS_CHECKPOINTED, true); \
- list_move_tail(&ne->list, &nm_i->nat_entries); \
- } while (0)
+ list_move_tail(&ne->list, &nm_i->nat_entries);
#define inc_node_version(version) (++version)

static inline void set_nat_flag(struct nat_entry *ne,
@@ -87,6 +82,14 @@ static inline bool get_nat_flag(struct nat_entry *ne, unsigned int type)
return ne->flag & mask;
}

+static inline void nat_reset_flag(struct nat_entry *ne)
+{
+ /* these states can be set only after checkpoint was done */
+ set_nat_flag(ne, IS_CHECKPOINTED, true);
+ set_nat_flag(ne, HAS_FSYNCED_INODE, false);
+ set_nat_flag(ne, HAS_LAST_FSYNC, true);
+}
+
static inline void node_info_from_raw_nat(struct node_info *ni,
struct f2fs_nat_entry *raw_ne)
{
--
1.8.5.2 (Apple Git-48)

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