Hi Al, ..and here is the other xattr change that was part of the nfsd user xattr support series that I mentioned in my previous email. Full series here: https://lore.kernel.org/linux-nfs/20200623223927.31795-1-fllinden@xxxxxxxxxx/ Any comments / concerned about this one? Thanks, - Frank On Tue, Jun 23, 2020 at 10:39:19PM +0000, Frank van der Linden wrote: > Add a function that checks is an extended attribute namespace is > supported for an inode, meaning that a handler must be present > for either the whole namespace, or at least one synthetic > xattr in the namespace. > > To be used by the nfs server code when being queried for extended > attributes support. > > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Frank van der Linden <fllinden@xxxxxxxxxx> > --- > fs/xattr.c | 27 +++++++++++++++++++++++++++ > include/linux/xattr.h | 2 ++ > 2 files changed, 29 insertions(+) > > diff --git a/fs/xattr.c b/fs/xattr.c > index 95f38f57347f..386b45676d7e 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c > @@ -134,6 +134,33 @@ xattr_permission(struct inode *inode, const char *name, int mask) > return inode_permission(inode, mask); > } > > +/* > + * Look for any handler that deals with the specified namespace. > + */ > +int > +xattr_supported_namespace(struct inode *inode, const char *prefix) > +{ > + const struct xattr_handler **handlers = inode->i_sb->s_xattr; > + const struct xattr_handler *handler; > + size_t preflen; > + > + if (!(inode->i_opflags & IOP_XATTR)) { > + if (unlikely(is_bad_inode(inode))) > + return -EIO; > + return -EOPNOTSUPP; > + } > + > + preflen = strlen(prefix); > + > + for_each_xattr_handler(handlers, handler) { > + if (!strncmp(xattr_prefix(handler), prefix, preflen)) > + return 0; > + } > + > + return -EOPNOTSUPP; > +} > +EXPORT_SYMBOL(xattr_supported_namespace); > + > int > __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name, > const void *value, size_t size, int flags) > diff --git a/include/linux/xattr.h b/include/linux/xattr.h > index a2f3cd02653c..fac75810d9d3 100644 > --- a/include/linux/xattr.h > +++ b/include/linux/xattr.h > @@ -61,6 +61,8 @@ ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_siz > ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name, > char **xattr_value, size_t size, gfp_t flags); > > +int xattr_supported_namespace(struct inode *inode, const char *prefix); > + > static inline const char *xattr_prefix(const struct xattr_handler *handler) > { > return handler->prefix ?: handler->name; > -- > 2.17.2 >
