[PATCH 3/8] ext4: Protect ext4_page_mkwrite & ext4_setattr with sb_start_write - sb_end_write
From: Jan Kara <jack@suse.cz>
Date: 2012-01-20 20:34:41
Also in:
linux-fsdevel, linux-xfs, lkml
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
Since ext4_page_mkwrite() calls into __block_page_mkwrite() it has to provide freezing protection on it's own. Also ext4_setattr() needs protection because ext4_truncate() can modify last page of the file. Acked-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Jan Kara <jack@suse.cz> --- fs/ext4/inode.c | 9 ++++----- 1 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 848f436..05d6328 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c@@ -4225,6 +4225,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) if (error) return error; + sb_start_write(inode->i_sb, SB_FREEZE_WRITE); if (is_quota_modification(inode, attr)) dquot_initialize(inode); if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
@@ -4327,6 +4328,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) rc = ext4_acl_chmod(inode); err_out: + sb_end_write(inode->i_sb, SB_FREEZE_WRITE); ext4_std_error(inode->i_sb, error); if (!error) error = rc;
@@ -4733,11 +4735,7 @@ int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) get_block_t *get_block; int retries = 0; - /* - * This check is racy but catches the common case. We rely on - * __block_page_mkwrite() to do a reliable check. - */ - vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); + sb_start_write(inode->i_sb, SB_FREEZE_WRITE); /* Delalloc case is easy... */ if (test_opt(inode->i_sb, DELALLOC) && !ext4_should_journal_data(inode) &&
@@ -4805,5 +4803,6 @@ retry_alloc: out_ret: ret = block_page_mkwrite_return(ret); out: + sb_end_write(inode->i_sb, SB_FREEZE_WRITE); return ret; }
--
1.7.1