Date: Fri, 15 Nov 2002 06:10:55 -0800 From: Chuck Tuffli <chuck_tuffli@agilent.com> To: freebsd-hackers@FreeBSD.ORG Subject: bus_dmamem_alloc failing Message-ID: <20021115141048.GA367@thegrail.rose.agilent.com>
next in thread | raw e-mail | index | archive | help
I'm writting a PCI device driver that needs to allocate "large"
aligned chunks of DMA memory for the hardware's queues. After loading
and unloading the driver a number of times, bus_dmamem_alloc starts to
fail.
In the device attach, the allocation code looks like (error checking
removed for brevity)
bus_dma_tag_create(NULL, 4, 0, BUS_SPACE_MAXADDR_32BIT,
BUS_SPACE_MAXADDR, NULL, NULL, BUS_SPACE_MAXSIZE_32BIT,
BUS_SPACE_MAXSIZE_32BIT, BUS_SPACE_UNRESTRICTED,
0, &parent);
bus_dma_tag_create(parent, 65536, 0, BUS_SPACE_MAXADDR_32BIT,
BUS_SPACE_MAXADDR, NULL, NULL, 65536, 1, 65536,
0, &child);
bus_dmamem_alloc(child, &virt, BUS_DMA_NOWAIT, &map);
bus_dmamap_load(child, map, virt, 65536, map_request, NULL, 0);
In the device detach, the code that frees up the memory
if (virt != NULL) {
bus_dmamap_unload(child, map);
bus_dmamem_free(child, virt, map);
bus_dmamap_destroy(child, map);
}
bus_dma_tag_destroy(child);
bus_dma_tag_destroy(parent);
I'm clearly doing something wrong, but I don't understand what the
problem is. Any ideas? Thanks!
--
Chuck Tuffli <chuck_tuffli AT NO_SPAM agilent DOT com>
Agilent Technologies, Storage and Networking
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20021115141048.GA367>