reiserfs: fixup xattr_root caching

The xattr_root caching was broken from my previous patch set. It wouldn't
 cause corruption, but could cause decreased performance due to allocating
 a larger chunk of the journal (~ 27 blocks) than it would actually use.

 This patch loads the xattr root dentry at xattr initialization and creates
 it on-demand. Since we're using the cached dentry, there's no point
 in keeping lookup_or_create_dir around, so that's removed.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Jeff Mahoney 2009-05-05 15:30:15 -04:00 коммит произвёл Al Viro
Родитель edcc37a047
Коммит ab17c4f021
3 изменённых файлов: 52 добавлений и 33 удалений

Просмотреть файл

@ -113,36 +113,28 @@ static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
/* Returns and possibly creates the xattr dir. */
static struct dentry *lookup_or_create_dir(struct dentry *parent,
const char *name, int flags)
{
struct dentry *dentry;
BUG_ON(!parent);
mutex_lock_nested(&parent->d_inode->i_mutex, I_MUTEX_XATTR);
dentry = lookup_one_len(name, parent, strlen(name));
if (!IS_ERR(dentry) && !dentry->d_inode) {
int err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_mkdir(parent->d_inode, dentry, 0700);
if (err) {
dput(dentry);
dentry = ERR_PTR(err);
}
}
mutex_unlock(&parent->d_inode->i_mutex);
return dentry;
}
static struct dentry *open_xa_root(struct super_block *sb, int flags)
{
struct dentry *privroot = REISERFS_SB(sb)->priv_root;
if (!privroot)
struct dentry *xaroot;
if (!privroot->d_inode)
return ERR_PTR(-ENODATA);
return lookup_or_create_dir(privroot, XAROOT_NAME, flags);
mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
xaroot = dget(REISERFS_SB(sb)->xattr_root);
if (!xaroot->d_inode) {
int err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
if (err) {
dput(xaroot);
xaroot = ERR_PTR(err);
}
}
mutex_unlock(&privroot->d_inode->i_mutex);
return xaroot;
}
static struct dentry *open_xa_dir(const struct inode *inode, int flags)
@ -158,10 +150,22 @@ static struct dentry *open_xa_dir(const struct inode *inode, int flags)
le32_to_cpu(INODE_PKEY(inode)->k_objectid),
inode->i_generation);
xadir = lookup_or_create_dir(xaroot, namebuf, flags);
mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
if (!IS_ERR(xadir) && !xadir->d_inode) {
int err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
if (err) {
dput(xadir);
xadir = ERR_PTR(err);
}
}
mutex_unlock(&xaroot->d_inode->i_mutex);
dput(xaroot);
return xadir;
}
/* The following are side effects of other operations that aren't explicitly
@ -986,19 +990,33 @@ int reiserfs_lookup_privroot(struct super_block *s)
int reiserfs_xattr_init(struct super_block *s, int mount_flags)
{
int err = 0;
struct dentry *privroot = REISERFS_SB(s)->priv_root;
#ifdef CONFIG_REISERFS_FS_XATTR
err = xattr_mount_check(s);
if (err)
goto error;
if (!REISERFS_SB(s)->priv_root->d_inode && !(mount_flags & MS_RDONLY)) {
if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
mutex_lock(&s->s_root->d_inode->i_mutex);
err = create_privroot(REISERFS_SB(s)->priv_root);
mutex_unlock(&s->s_root->d_inode->i_mutex);
}
if (!err)
if (privroot->d_inode) {
s->s_xattr = reiserfs_xattr_handlers;
mutex_lock(&privroot->d_inode->i_mutex);
if (!REISERFS_SB(s)->xattr_root) {
struct dentry *dentry;
dentry = lookup_one_len(XAROOT_NAME, privroot,
strlen(XAROOT_NAME));
if (!IS_ERR(dentry))
REISERFS_SB(s)->xattr_root = dentry;
else
err = PTR_ERR(dentry);
}
mutex_unlock(&privroot->d_inode->i_mutex);
}
error:
if (err) {
@ -1008,11 +1026,12 @@ error:
#endif
/* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
s->s_flags = s->s_flags & ~MS_POSIXACL;
#ifdef CONFIG_REISERFS_FS_POSIX_ACL
if (reiserfs_posixacl(s))
s->s_flags |= MS_POSIXACL;
else
#endif
s->s_flags &= ~MS_POSIXACL;
return err;
}

Просмотреть файл

@ -402,7 +402,7 @@ struct reiserfs_sb_info {
int reserved_blocks; /* amount of blocks reserved for further allocations */
spinlock_t bitmap_lock; /* this lock on now only used to protect reserved_blocks variable */
struct dentry *priv_root; /* root of /.reiserfs_priv */
struct dentry *xattr_root; /* root of /.reiserfs_priv/.xa */
struct dentry *xattr_root; /* root of /.reiserfs_priv/xattrs */
int j_errno;
#ifdef CONFIG_QUOTA
char *s_qf_names[MAXQUOTAS];

Просмотреть файл

@ -98,7 +98,7 @@ static inline size_t reiserfs_xattr_jcreate_nblocks(struct inode *inode)
if ((REISERFS_I(inode)->i_flags & i_has_xattr_dir) == 0) {
nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
if (REISERFS_SB(inode->i_sb)->xattr_root == NULL)
if (!REISERFS_SB(inode->i_sb)->xattr_root->d_inode)
nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
}