On 2023/8/31 18:48, Li Yiyan wrote:
...
+
+ vi->sbi = &sbi;
+ vi->nid = (erofs_nid_t)ino;
+ ret = erofs_read_inode_from_disk(vi);
+ if (ret < 0) {
+ fuse_reply_err(req, EIO);
Maybe reply -ret? Since there are other errors in
erofs_read_inode_from_disk.
No. As mentioned in declaration, param err represents the *positive* error
value,
or zero for success.
I think Jianan meant:
if (ret < 0) {
fuse_reply_err(req, -err);
instead.
...
+ return;
+ }
+
+ if (bufsize == 0)
+ bufsize = EROFSFUSE_XATTR_BUF_SIZE;
Why do we need to reconfigure bufsize here? erofs_listxattr should
handle bufsize of 0.
This is a workaround for the time being, I will propose a patch to modify the
lib
to solve this problem.
As mentioned in https://man7.org/linux/man-pages/man2/listxattr.2.html:
"If size is specified as zero, these calls return the current size of the list
of
extended attribute names ( and leave list unchanged). This can be used to
determine
the size of the buffer that should be supplied in a subsequent call."
Therefore, buf=0 means that we need to use fuse_reply_xattr to return the
requested
size of the buffer. Only when buf is not 0 do we need to copy xattr to buffer.
At present, the erofs_getxattr cannot solve this problem, so a workaround is
made on the fuse layer to temporarily solve this problem and
control the extent of the patch.
Are you sure that erofs_listxattr() cannot accept NULL buffers?
I'm totally confused.
Anyway, if erofs_listxattr() unmeet your requirement for whatever
reasons, please fix this instead.
Thanks,
Gao Xiang
