util/vfio-helpers: Extract qemu_vfio_water_mark_reached()

Extract qemu_vfio_water_mark_reached() for readability,
and have it provide an error hint it its Error* handle.

Suggested-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-8-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Philippe Mathieu-Daudé 2021-09-02 09:00:21 +02:00 committed by Stefan Hajnoczi
parent 521b97cd4e
commit 71e3038c15

View File

@ -721,6 +721,21 @@ qemu_vfio_find_temp_iova(QEMUVFIOState *s, size_t size, uint64_t *iova)
return -ENOMEM;
}
/**
* qemu_vfio_water_mark_reached:
*
* Returns %true if high watermark has been reached, %false otherwise.
*/
static bool qemu_vfio_water_mark_reached(QEMUVFIOState *s, size_t size,
Error **errp)
{
if (s->high_water_mark - s->low_water_mark + 1 < size) {
error_setg(errp, "iova exhausted (water mark reached)");
return true;
}
return false;
}
/* Map [host, host + size) area into a contiguous IOVA address space, and store
* the result in @iova if not NULL. The caller need to make sure the area is
* aligned to page size, and mustn't overlap with existing mapping areas (split
@ -742,7 +757,7 @@ int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size,
if (mapping) {
iova0 = mapping->iova + ((uint8_t *)host - (uint8_t *)mapping->host);
} else {
if (s->high_water_mark - s->low_water_mark + 1 < size) {
if (qemu_vfio_water_mark_reached(s, size, errp)) {
ret = -ENOMEM;
goto out;
}