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ubifs: Remove ui_mutex in ubifs_xattr_get and change_xattr

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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
1 changed files with 0 additions and 4 deletions
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4
fs/ubifs/xattr.c
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@@ -208,13 +208,11 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
err = -ENOMEM; err = -ENOMEM;
goto out_free; goto out_free;
} }
mutex_lock(&ui->ui_mutex);
kfree(ui->data); kfree(ui->data);
ui->data = buf; ui->data = buf;
inode->i_size = ui->ui_size = size; inode->i_size = ui->ui_size = size;
old_size = ui->data_len; old_size = ui->data_len;
ui->data_len = size; ui->data_len = size;
mutex_unlock(&ui->ui_mutex);
mutex_lock(&host_ui->ui_mutex); mutex_lock(&host_ui->ui_mutex);
host->i_ctime = current_time(host); 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, inode->i_size == ui->data_len);
ubifs_assert(c, ubifs_inode(host)->xattr_size > ui->data_len); ubifs_assert(c, ubifs_inode(host)->xattr_size > ui->data_len);
mutex_lock(&ui->ui_mutex);
if (buf) { if (buf) {
/* If @buf is %NULL we are supposed to return the length */ /* If @buf is %NULL we are supposed to return the length */
if (ui->data_len > size) { 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; err = ui->data_len;
out_iput: out_iput:
mutex_unlock(&ui->ui_mutex);
iput(inode); iput(inode);
out_cleanup: out_cleanup:
up_read(&ubifs_inode(host)->xattr_sem); up_read(&ubifs_inode(host)->xattr_sem);