Part I: Update extended attribute API and ABI:

o Modify the system call syntax for extattr_{get,set}_{fd,file}() so
  as not to use the scatter gather API (which appeared not to be used
  by any consumers, and be less portable), rather, accepts 'data'
  and 'nbytes' in the style of other simple read/write interfaces.
  This changes the API and ABI.

o Modify system call semantics so that extattr_get_{fd,file}() return
  a size_t.  When performing a read, the number of bytes read will
  be returned, unless the data pointer is NULL, in which case the
  number of bytes of data are returned.  This changes the API only.

o Modify the VOP_GETEXTATTR() vnode operation to accept a *size_t
  argument so as to return the size, if desirable.  If set to NULL,
  the size will not be returned.

o Update various filesystems (pseodofs, ufs) to DTRT.

These changes should make extended attributes more useful and more
portable.  More commits to rebuild the system call files, as well
as update userland utilities to follow.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs

2 files changed, 2 insertions, 2 deletions

diff --git a/sys/fs/pseudofs/pseudofs.h b/sys/fs/pseudofs/pseudofs.h
index ba0a93b..4017978 100644
--- a/sys/fs/pseudofs/pseudofs.h
+++ b/sys/fs/pseudofs/pseudofs.h
@@ -138,7 +138,7 @@ typedef int (*pfs_ioctl_t)(PFS_IOCTL_ARGS);
 #define PFS_GETEXTATTR_ARGS \
 	struct thread *td, struct proc *p, struct pfs_node *pn, \
 	int attrnamespace, const char *name, struct uio *uio,	\
-	struct ucred *cred
+	size_t *size, struct ucred *cred
 #define PFS_GETEXTATTR_PROTO(name) \
 	int name(PFS_GETEXTATTR_ARGS);
 struct ucred;
diff --git a/sys/fs/pseudofs/pseudofs_vnops.c b/sys/fs/pseudofs/pseudofs_vnops.c
index 0c8bdc3..42662ea 100644
--- a/sys/fs/pseudofs/pseudofs_vnops.c
+++ b/sys/fs/pseudofs/pseudofs_vnops.c
@@ -283,7 +283,7 @@ pfs_getextattr(struct vop_getextattr_args *va)
 	}
 	
 	error = (pn->pn_getextattr)(curthread, proc, pn, va->a_attrnamespace,
-	    va->a_name, va->a_uio, va->a_cred);
+	    va->a_name, va->a_uio, va->a_size, va->a_cred);
 
 	if (proc != NULL)
 		PRELE(proc);