These helpers do a full transfer from an in-memory buffer to target
memory, with support for scatter/gather lists. It will be used to
store the reply of an emulated command into a QEMUSGList provided by
the adapter.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
scsi-disk will manage scatter/gather list, but it does not create
single entries so it remains target-independent. Make QEMUSGList
available to it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch uses the newly created dma_addr_t type throughout the
scatter/gather handling code in dma-helpers.c whenever we need to
represent a dma bus address. This makes a better distinction as to
what is a bus address and what is a cpu physical address. Since we
don't support IOMMUs yet, they can't be very different for now, but
that will change in future, and this preliminary helps clarify what's
going on.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
As a preliminary to adding more extensive DMA and IOMMU infrastructure
support into qemu, this patch defines a dma_addr_t for storing DMA bus
addresses and a DMADirection enum which describes whether a DMA is
from an external device to main memory or from main memory to an
external device.
For now dma_addr_t is just defined to be target_phys_addr_t, but in
future, we can change this to support machines where we have bus
addresses which don't necessarily have the same format as CPU physical
addresses.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Target-independent code cannot construct sglists, but it can take
them from the outside as a black box. Allow this.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Move the QEMUSGList typedef to qemu-common so it can easily be used.
The actual struct definition stays in dma.h.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Make dma_bdrv_io available for drivers, and pass an explicit I/O function
instead of hardcoding bdrv_aio_readv/bdrv_aio_writev. This is required
to implement non-READ/WRITE dma commands in the ide driver, e.g. the
upcoming TRIM support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In the very least, a change like this requires discussion on the list.
The naming convention is goofy and it causes a massive merge problem. Something
like this _must_ be presented on the list first so people can provide input
and cope with it.
This reverts commit 99a0949b72.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Now that we have a separate aio pool structure we can remove those
aio pool details from BlockDriver.
Every driver supporting AIO now needs to declare a static AIOPool
with the aiocb size and the cancellation method. This cleans up the
current code considerably and will make it cleaner and more obvious
to support two different aio implementations behind a single
BlockDriver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The only target dependency for most hardware is sizeof(target_phys_addr_t).
Build these files into a convenience library, and use that instead of
building for every target.
Remove and poison various target specific macros to avoid bogus target
dependencies creeping back in.
Big/Little endian is not handled because devices should not know or care
about this to start with.
Signed-off-by: Paul Brook <paul@codesourcery.com>
Move the dma helpers to a private aio pool, and implement a cancellation
method for them. Should prevent issues when cancelling I/O while dma is
in progress.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6872 c046a42c-6fe2-441c-8c8c-71466251a162
These helpers perform read/write requests on entire scatter/gather lists,
relieving the device emulation code from mapping and unmapping physical
memory, and from looping when map resources are exhausted.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6524 c046a42c-6fe2-441c-8c8c-71466251a162
Scatter-gather lists are used extensively in dma-capable devices; a
single data structure allows more code reuse later on.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6522 c046a42c-6fe2-441c-8c8c-71466251a162
