diff options
Diffstat (limited to 'drivers/lguest/io.c')
-rw-r--r-- | drivers/lguest/io.c | 10 |
1 files changed, 10 insertions, 0 deletions
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) | |||
553 | up_read(&lg->mm->mmap_sem); | 553 | up_read(&lg->mm->mmap_sem); |
554 | } | 554 | } |
555 | 555 | ||
556 | /*M:007 We only return a single DMA buffer to the Launcher, but it would be | ||
557 | * more efficient to return a pointer to the entire array of DMA buffers, which | ||
558 | * it can cache and choose one whenever it wants. | ||
559 | * | ||
560 | * Currently the Launcher uses a write to /dev/lguest, and the return value is | ||
561 | * the address of the DMA structure with the interrupt number placed in | ||
562 | * dma->used_len. If we wanted to return the entire array, we need to return | ||
563 | * the address, array size and interrupt number: this seems to require an | ||
564 | * ioctl(). :*/ | ||
565 | |||
556 | /*L:320 This routine looks for a DMA buffer registered by the Guest on the | 566 | /*L:320 This routine looks for a DMA buffer registered by the Guest on the |
557 | * given key (using the BIND_DMA hypercall). */ | 567 | * given key (using the BIND_DMA hypercall). */ |
558 | unsigned long get_dma_buffer(struct lguest *lg, | 568 | unsigned long get_dma_buffer(struct lguest *lg, |