On Thu, Jun 25, 2020 at 08:41:57PM +0000, Frank van der Linden wrote: > 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 Hi Al, Here's the other one I'm just sending a quick ping on. It's a simple change - just add a little new function that enables nfsd to check if the "user." namespace is at all supported by a filesystem. Any comments? Again, Linus - this is a pretty small change, doesn't affect any existing codepaths, and it's already in the tree Chuck is setting up for 5.9. Could this go in through that directly? 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 > >
