Summary
Supply pages into a pager owned VMO.
Declaration
#include <zircon/syscalls.h>
zx_status_t zx_pager_supply_pages(zx_handle_t pager,
zx_handle_t pager_vmo,
uint64_t offset,
uint64_t length,
zx_handle_t aux_vmo,
uint64_t aux_offset);
Description
Moves the pages of aux_vmo in the range [aux_offset, aux_offset + length) to pager_vmo in the range [offset, offset + length). Any pages in pager_vmo in the specified range will not be replaced; instead the corresponding pages from aux_vmo will be freed. aux_vmo cannot be physical, contiguous, or pager-backed, and must have no pinned pages in the specified range. Any uncommitted pages in aux_vmo will cause zero pages, or equivalent, to be inserted into pager_vmo. After this operation, the specified region of aux_vmo will be fully decommitted.
Rights
pager must be of type ZX_OBJ_TYPE_PAGER and have ZX_RIGHT_MANAGE_VMO.
pager_vmo must be of type ZX_OBJ_TYPE_VMO and have ZX_RIGHT_WRITE.
aux_vmo must be of type ZX_OBJ_TYPE_VMO and have ZX_RIGHT_READ and ZX_RIGHT_WRITE.
Return value
zx_pager_supply_pages() returns ZX_OK on success, or one of the following error codes on failure.
On failure the specified range of aux_vmo may be either untouched or fully decommitted. If
aux_vmo is decommitted, then an unspecified number of pages in pager_vmo will have been
populated.
Errors
ZX_ERR_BAD_HANDLE pager, pager_vmo, or aux_vmo is not a valid handle.
ZX_ERR_WRONG_TYPE pager is not a pager handle, pager_vmo is not a VMO handle, or
aux_vmo is not a VMO handle.
ZX_ERR_INVALID_ARGS pager_vmo is not a VMO created from pager, or offset, size,
or aux_offset is not page aligned.
ZX_ERR_ACCESS_DENIED pager does not have ZX_RIGHT_MANAGE_VMO, or aux_vmo does not have
ZX_RIGHT_READ or ZX_RIGHT_WRITE, or pager_vmo does not have ZX_RIGHT_WRITE.
ZX_ERR_BAD_STATE aux_vmo is not in a state where it can supply the required pages, or
pager_vmo has been detached from the pager.
ZX_ERR_NOT_SUPPORTED aux_vmo is a physical, contiguous, or pager-backed VMO.
ZX_ERR_OUT_OF_RANGE The specified range in pager_vmo or aux_vmo is invalid.
ZX_ERR_NO_MEMORY Failure due to lack of memory.