ubifs: Remove ui_mutex in ubifs_xattr_get and change_xattr

Since ubifs_xattr_get and ubifs_xattr_set cannot being executed
parallelly after importing @host_ui->xattr_sem, now we can remove
ui_mutex imported by commit ab92a20bce ("ubifs: make
ubifs_[get|set]xattr atomic").

@xattr_size, @xattr_names and @xattr_cnt can't be out of protection
by @host_ui->mutex yet, they are sill accesed in other places, such as
pack_inode() called by ubifs_write_inode() triggered by page-writeback.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Zhihao Cheng 2021-05-31 20:52:10 +08:00 committed by Richard Weinberger
parent f4e3634a3b
commit 819f9ab430

View File

@ -208,13 +208,11 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
err = -ENOMEM;
goto out_free;
}
mutex_lock(&ui->ui_mutex);
kfree(ui->data);
ui->data = buf;
inode->i_size = ui->ui_size = size;
old_size = ui->data_len;
ui->data_len = size;
mutex_unlock(&ui->ui_mutex);
mutex_lock(&host_ui->ui_mutex);
host->i_ctime = current_time(host);
@ -362,7 +360,6 @@ ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
ubifs_assert(c, inode->i_size == ui->data_len);
ubifs_assert(c, ubifs_inode(host)->xattr_size > ui->data_len);
mutex_lock(&ui->ui_mutex);
if (buf) {
/* If @buf is %NULL we are supposed to return the length */
if (ui->data_len > size) {
@ -375,7 +372,6 @@ ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
err = ui->data_len;
out_iput:
mutex_unlock(&ui->ui_mutex);
iput(inode);
out_cleanup:
up_read(&ubifs_inode(host)->xattr_sem);