bp_mapin - allocate virtual address space
#include <sys/types.h> #include <sys/buf.h> void bp_mapin(struct buf *bp);
Architecture independent level 1 (DDI/DKI).
bp
bp_mapin() is used to map virtual address space to a page list maintained by the buffer header during a paged- I/O request. bp_mapin() allocates system virtual address space, maps that space to the page list, and returns the starting address of the space in the bp->b_un.b_addr field of the buf(9S) structure. Virtual address space is then deallocated using the bp_mapout(9F) function.
If a null page list is encountered, bp_mapin() returns without allocating space and no mapping is performed.
bp_mapin() can be called from user and kernel contexts.
Writing Device Drivers
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Created 1996-2024 by Maxim Chirkov Добавить, Поддержать, Вебмастеру |