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Message-id: <1375343917-24093-1-git-send-email-jaegeuk.kim@samsung.com>
Date: Thu, 01 Aug 2013 16:58:37 +0900
From: Jaegeuk Kim <jaegeuk.kim@...sung.com>
To: unlisted-recipients:; (no To-header on input)
Cc: Jaegeuk Kim <jaegeuk.kim@...sung.com>,
linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-f2fs-devel@...ts.sourceforge.net
Subject: [PATCH] f2fs: fix handling orphan inodes
This patch fixes mishandling of the sbi->n_orphans variable.
If users request lots of f2fs_unlink(), check_orphan_space() could be contended.
In such the case, sbi->n_orphans can be read incorrectly so that f2fs_unlink()
would fall into the wrong state which results in the failure of
add_orphan_inode().
So, let's increment sbi->n_orphans virtually prior to the actual orphan inode
stuffs. After that, let's release sbi->n_orphans by calling release_orphan_inode
or remove_orphan_inode.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@...sung.com>
---
fs/f2fs/checkpoint.c | 13 ++++++++++---
fs/f2fs/dir.c | 2 ++
fs/f2fs/f2fs.h | 3 ++-
fs/f2fs/namei.c | 19 ++++++++++++++-----
4 files changed, 28 insertions(+), 9 deletions(-)
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index fe91773..c5a5c39 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -182,7 +182,7 @@ const struct address_space_operations f2fs_meta_aops = {
.set_page_dirty = f2fs_set_meta_page_dirty,
};
-int check_orphan_space(struct f2fs_sb_info *sbi)
+int acquire_orphan_inode(struct f2fs_sb_info *sbi)
{
unsigned int max_orphans;
int err = 0;
@@ -197,10 +197,19 @@ int check_orphan_space(struct f2fs_sb_info *sbi)
mutex_lock(&sbi->orphan_inode_mutex);
if (sbi->n_orphans >= max_orphans)
err = -ENOSPC;
+ else
+ sbi->n_orphans++;
mutex_unlock(&sbi->orphan_inode_mutex);
return err;
}
+void release_orphan_inode(struct f2fs_sb_info *sbi)
+{
+ mutex_lock(&sbi->orphan_inode_mutex);
+ sbi->n_orphans--;
+ mutex_unlock(&sbi->orphan_inode_mutex);
+}
+
void add_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
{
struct list_head *head, *this;
@@ -229,8 +238,6 @@ retry:
list_add(&new->list, this->prev);
else
list_add_tail(&new->list, head);
-
- sbi->n_orphans++;
out:
mutex_unlock(&sbi->orphan_inode_mutex);
}
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index d1bb260..384c6da 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -572,6 +572,8 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
if (inode->i_nlink == 0)
add_orphan_inode(sbi, inode->i_ino);
+ else
+ release_orphan_inode(sbi);
}
if (bit_pos == NR_DENTRY_IN_BLOCK) {
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index a6858c7..78777cd 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1044,7 +1044,8 @@ void destroy_segment_manager(struct f2fs_sb_info *);
struct page *grab_meta_page(struct f2fs_sb_info *, pgoff_t);
struct page *get_meta_page(struct f2fs_sb_info *, pgoff_t);
long sync_meta_pages(struct f2fs_sb_info *, enum page_type, long);
-int check_orphan_space(struct f2fs_sb_info *);
+int acquire_orphan_inode(struct f2fs_sb_info *);
+void release_orphan_inode(struct f2fs_sb_info *);
void add_orphan_inode(struct f2fs_sb_info *, nid_t);
void remove_orphan_inode(struct f2fs_sb_info *, nid_t);
int recover_orphan_inodes(struct f2fs_sb_info *);
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 3297278..4e47518 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -239,7 +239,7 @@ static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
if (!de)
goto fail;
- err = check_orphan_space(sbi);
+ err = acquire_orphan_inode(sbi);
if (err) {
kunmap(page);
f2fs_put_page(page, 0);
@@ -393,7 +393,7 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *old_inode = old_dentry->d_inode;
struct inode *new_inode = new_dentry->d_inode;
struct page *old_dir_page;
- struct page *old_page;
+ struct page *old_page, *new_page;
struct f2fs_dir_entry *old_dir_entry = NULL;
struct f2fs_dir_entry *old_entry;
struct f2fs_dir_entry *new_entry;
@@ -415,7 +415,6 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
ilock = mutex_lock_op(sbi);
if (new_inode) {
- struct page *new_page;
err = -ENOTEMPTY;
if (old_dir_entry && !f2fs_empty_dir(new_inode))
@@ -427,9 +426,13 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
if (!new_entry)
goto out_dir;
+ err = acquire_orphan_inode(sbi);
+ if (err)
+ goto put_out_dir;
+
if (update_dent_inode(old_inode, &new_dentry->d_name)) {
- f2fs_put_page(new_page, 1);
- goto out_dir;
+ release_orphan_inode(sbi);
+ goto put_out_dir;
}
f2fs_set_link(new_dir, new_entry, new_page, old_inode);
@@ -438,8 +441,12 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
if (old_dir_entry)
drop_nlink(new_inode);
drop_nlink(new_inode);
+
if (!new_inode->i_nlink)
add_orphan_inode(sbi, new_inode->i_ino);
+ else
+ release_orphan_inode(sbi);
+
update_inode_page(new_inode);
} else {
err = f2fs_add_link(new_dentry, old_inode);
@@ -472,6 +479,8 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
mutex_unlock_op(sbi, ilock);
return 0;
+put_out_dir:
+ f2fs_put_page(new_page, 1);
out_dir:
if (old_dir_entry) {
kunmap(old_dir_page);
--
1.8.3.1.437.g0dbd812
--
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