scsi_sync_pkt(9F) Kernel Functions for Drivers scsi_sync_pkt(9F)
NAME
scsi_sync_pkt - synchronize CPU and I/O views of memory
SYNOPSIS
#include <sys/scsi/scsi.h>
void scsi_sync_pkt(struct scsi_pkt *pktp);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI).
PARAMETERS
pktp Pointer to a scsi_pkt(9S) structure.
DESCRIPTION
scsi_sync_pkt() is used to selectively synchronize a CPU's or device's view of the data associated with the SCSI packet that has been
mapped for I/O. This may involve operations such as flushes of CPU or I/O caches, as well as other more complex operations such as stalling
until hardware write buffers have drained.
This function need only be called under certain circumstances. When a SCSI packet is mapped for I/O using scsi_init_pkt(9F) and destroyed
using scsi_destroy_pkt(9F), then an implicit scsi_sync_pkt() will be performed. However, if the memory object has been modified by either
the device or a CPU after the mapping by scsi_init_pkt(9F), then a call to scsi_sync_pkt() is required.
If the same scsi_pkt is reused for a data transfer from memory to a device, then scsi_sync_pkt() must be called before calling scsi_trans-
port(9F). If the same packet is reused for a data transfer from a device to memory scsi_sync_pkt() must be called after the completion of
the packet but before accessing the data in memory.
CONTEXT
scsi_sync_pkt() may be called from user or interrupt context.
SEE ALSO
tran_sync_pkt(9E), ddi_dma_sync(9F), scsi_destroy_pkt(9F), scsi_init_pkt(9F), scsi_transport(9F), scsi_pkt(9S)
Writing Device Drivers
SunOS 5.10 25 Feb 1994 scsi_sync_pkt(9F)
