From f56a384e98aa81065038c4e16f39ed989ccae687 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 26 Jul 2007 10:41:05 -0700 Subject: lguest: documentation VII: FIXMEs Documentation: The FIXMEs Signed-off-by: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/lguest/io.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/lguest/io.c') diff --git a/drivers/lguest/io.c b/drivers/lguest/io.c index da288128e44f..ea68613b43f6 100644 --- a/drivers/lguest/io.c +++ b/drivers/lguest/io.c @@ -553,6 +553,16 @@ void release_all_dma(struct lguest *lg) up_read(&lg->mm->mmap_sem); } +/*M:007 We only return a single DMA buffer to the Launcher, but it would be + * more efficient to return a pointer to the entire array of DMA buffers, which + * it can cache and choose one whenever it wants. + * + * Currently the Launcher uses a write to /dev/lguest, and the return value is + * the address of the DMA structure with the interrupt number placed in + * dma->used_len. If we wanted to return the entire array, we need to return + * the address, array size and interrupt number: this seems to require an + * ioctl(). :*/ + /*L:320 This routine looks for a DMA buffer registered by the Guest on the * given key (using the BIND_DMA hypercall). */ unsigned long get_dma_buffer(struct lguest *lg, -- cgit v1.2.2