getnextpg(D3DK) —

.IX \f4getnextpg\fP(D3DK)

NAME

getnextpg − get next page pointer

SYNOPSIS

#include <sys/types.h>
#include <vm/page.h>
#include <sys/buf.h>
page_t ∗getnextpg(buf_t ∗bp, page_t ∗pp);

ARGUMENTS

bpPointer to the buffer header structure.

ppPointer to the previous page structure returned.

DESCRIPTION

getnextpg will return a pointer to the next page in a buffer header’s page list [see buf(D4DK)] during a paged-I/O request. A paged-I/O request is identified by the B_PAGEIO flag being set in the b_flags field of the buffer header passed to a driver’s strategy(D2DK) routine.

Given a buffer header, bp, and a pointer to the page, pp, returned from the previous call to getnextpg, the next page is returned. If pp is NULL, the first page in the page list is returned.

RETURN VALUE

On success, a pointer to the next page structure in the page list is returned. If the end of the list is reached, NULL is returned.

LEVEL

Base or Interrupt.

NOTES

Does not sleep. Driver defined basic locks, read/write locks, and sleep locks may be held across calls to this function.

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