Index for Section 9r

Alphabetical listing for B

Bottom of page

BUF_LOCK(9r)
NAME
  BUF_LOCK - General: Locks the specified I/O buffer

SYNOPSIS
  void BUF_LOCK(
	  struct buf *bp );

ARGUMENTS
  bp  Specifies a pointer to a buf structure.

DESCRIPTION
  The BUF_LOCK routine locks the specified I/O buffer.	The routine masks all
  disk and tape controller interrupts (by calling the splbio routine). It
  sets the mutual exclusion buffer lock member, b_lock, of the specified buf
  structure pointer.

  The BUF_LOCK routine then sets the b_flags member of the specified buf
  structure pointer to B_BUSY to indicate that this buffer is being used.
  Finally, BUF_LOCK resets the CPU priority level (by calling the splx
  routine).

NOTES
  You should design in your kernel modules to hold the I/O buffer lock for as
  short a period of time as possible to allow maximum concurrency. You should
  also release the I/O buffer lock by calling the BUF_UNLOCK routine before
  returning from the module's entry point.

RETURN VALUES
  None

SEE ALSO
  Routines: BUF_UNLOCK(9r)

Index for Section 9r

Alphabetical listing for B

Top of page