DUMP(9E) Driver Entry Points DUMP(9E)

dump - dump memory to device during system failure

#include <sys/types.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
int dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);

illumos specific (illumos DDI). This entry point is required. For drivers that do not implement dump() routines, nodev(9F) should be used.


Device number.


Address for the beginning of the area to be dumped.


Block offset to dump memory.


Number of blocks to dump.

dump() is used to dump a portion of virtual address space directly to a device in the case of system failure. It can also be used for checking the state of the kernel during a checkpoint operation. The memory area to be dumped is specified by addr (base address) and nblk (length). It is dumped to the device specified by dev starting at offset blkno. Upon completion dump() returns the status of the transfer.

When the system is panicking, the calls of functions scheduled by timeout(9F) and ddi_trigger_softintr(9F) will never occur. Neither can delay(9F) be relied upon, since it is implemented via timeout(). See ddi_in_panic(9F).

dump() is called at interrupt priority.

dump() returns 0 on success, or the appropriate error number.

cpr(4), nodev(9F)

Writing Device Drivers

October 9, 2001 OmniOS