There's a typo in the comments right before biodone() in vfs_bio.c:
The right page for the quote about biodone in the Leffler, et al. book
is 247, not 274.

Onno van der Linden   c/o     vdlinden@fwi.uva.nl (Frank van der Linden)
*** /sys/kern/vfs_bio.c.orig	Sun Jun  5 13:31:32 1994
--- /sys/kern/vfs_bio.c	Sun Jun  5 13:31:48 1994
***************
*** 756,760 ****
   * daemon, do so. Otherwise, awaken waiting processes.
   *
!  * [ Leffler, et al., says on p.274:
   *	"This routine wakes up the blocked process, frees the buffer
   *	for an asynchronous write, or, for a request by the pagedaemon
--- 756,760 ----
   * daemon, do so. Otherwise, awaken waiting processes.
   *
!  * [ Leffler, et al., says on p.247:
   *	"This routine wakes up the blocked process, frees the buffer
   *	for an asynchronous write, or, for a request by the pagedaemon

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