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+/* -*- asm -*- ----------------------------------------------------------- *
+ *
+ * Copyright 2013 H. Peter Anvin - All Rights Reserved
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall
+ * be included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+#include "v9fs.h"
+
+ .code16
+ .section ".rtext","ax"
+
+/* ------------------------------------------------------------------------- *
+ * path_walk
+ *
+ * Issue a walk message for the path in FS:SI.
+ * BX marks the end of the path to convert, and EAX is the new fid.
+ * ------------------------------------------------------------------------- */
+
+ .globl path_walk
+path_walk:
+ movw msgbuf7,%di
+ movl $ROOT_FID,(%di)
+ movl %eax,4(%di)
+ addw $8,%di
+ pushw %di
+ call genpath
+ popw %si
+ pushw (%di) /* Number of pathname chunks */
+ movb $P9_TWALK,%al
+ call simple_message
+ jc 1f /* Message error */
+ popw %dx
+ movw (%di),%cx /* %ax = nwqid */
+ imul $13,%cx,%bx /* Each qid is 13 bytes */
+ movb $-11(%bx,%di),%al /* Type of the final QID */
+ cmpw %dx,%cx
+ jne 2f
+ clc /* All good */
+1:
+ retw
+2:
+ /*
+ * We receieved a subset of the desired qids. If the final
+ * component is a directory, this is ENOENT, otherwise ENOTDIR.
+ */
+ testb $P9_QTDIR,%al
+ movw $L_ENOENT,%ax
+ je 3f
+ movw $L_ENOTDIR,%ax
+3:
+ stc
+ retw