NFS3 MKNOD + btrfs Readdir: 351/351 PASS

NFS3 MKNOD (proc 13) completes all 17 standard NFS3 procedures — device file creation with sattr3, BLK/CHR device_data encoding. btrfs subdirectory readdir adds component-walk (btrfs_lookup_dir + btrfs_readdir_in). 351/351 ALL PASS. (sigil-fs 555bc3a, 7a3db76)

NFS3 MKNOD (nfs3_mknod.sg, 555bc3a)

Implements NFS3 procedure 13: device file creation. Call signature:

nfs3_mknod_call(buf, xid, dir_fh_id, name_ptr, name_len, ftype, major, minor)

Wire format on the XDR buffer:

• [dir_fh] — directory file handle
• [name] — filename as XDR opaque
• [type(4)] — NFS3 file type constant
• [sattr3(24)] — set-attributes structure (nfs3_sattr3_zero() helper emits the "don't set" form)
• [device_data(8)] — major/minor pair, emitted only for BLK and CHR types

Type constants: REG, DIR, BLK, CHR, LNK, SOCK, FIFO.

All 17 NFS3 procedures

With MKNOD landing, every standard NFS3 procedure (procs 0–17) is implemented.

btrfs subdirectory readdir (7a3db76)

The last stub in vfsdev_readdir_path is closed. Two new primitives enable subdirectory traversal inside a btrfs volume:

btrfs_lookup_dir

btrfs_lookup_dir(parent_oid, name_ptr, namelen) → child objectid. Scans DIR_ITEM (item type 84) entries for the given parent objectid in the current B-tree leaf, matching by name. Returns the child directory's objectid on success.

btrfs_readdir_in

btrfs_readdir_in(oid, index, ent) → 1/0. Scans DIR_INDEX (item type 96) entries for the given objectid. Entry layout matches btrfs_readdir: location.objectid at offset 0, di_type at offset 8, name_len at offset 9, name bytes starting at offset 10.

Component-walk in vfsdev_readdir_path

The btrfs nested case in vfsdev_readdir_path now performs a full component-walk loop:

for each path component:
  copy_comp(component)
  skip_slashes(path)
  btrfs_lookup_dir(current_oid, comp, comp_len) → child_oid
  current_oid = child_oid

btrfs_readdir_in(current_oid, index, ent)  // final directory

This closes the last vfsdev_readdir_path stub. Paths of arbitrary depth are now traversable in btrfs volumes without falling back to a stub return.

351/351

The harness stood at 350/350 before MKNOD. Adding nfs3_mknod.sg adds one procedure test; the btrfs component-walk adds coverage for nested paths. Final count: