scsi_sync_pkt(9F) Kernel Functions for Drivers scsi_sync_pkt(9F)NAMEscsi_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
The scsi_sync_pkt() function 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
The scsi_sync_pkt() function may be called from user, interrupt, or
kernel context.
SEE ALSOtran_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 16 Jan 2006 scsi_sync_pkt(9F)
