From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [PATCH 4/5] pci-assign: Convert need_emulate_cmd into a bitmask Date: Mon, 13 Dec 2010 16:56:29 -0700 Message-ID: <1292284589.2857.139.camel@x201> References: <89c6067f3e4ab9eca18f433972595039b266d62e.1292282738.git.jan.kiszka@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Marcelo Tosatti , kvm@vger.kernel.org, "Michael S. Tsirkin" , Jan Kiszka To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:40146 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756767Ab0LMX4d (ORCPT ); Mon, 13 Dec 2010 18:56:33 -0500 In-Reply-To: <89c6067f3e4ab9eca18f433972595039b266d62e.1292282738.git.jan.kiszka@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On Tue, 2010-12-14 at 00:25 +0100, Jan Kiszka wrote: > From: Jan Kiszka > > Define a mask of PCI command register bits that need to be emulated, > i.e. read back from their shadow state. We will need this for > selectively emulating the INTx mask bit. > > Note: No initialization of emulate_cmd_mask to zero needed, the device > state is already zero-initialized. > > Signed-off-by: Jan Kiszka > --- > hw/device-assignment.c | 18 ++++++++++-------- > hw/device-assignment.h | 2 +- > 2 files changed, 11 insertions(+), 9 deletions(-) > > diff --git a/hw/device-assignment.c b/hw/device-assignment.c > index ef045f4..26d3bd7 100644 > --- a/hw/device-assignment.c > +++ b/hw/device-assignment.c > @@ -525,14 +525,17 @@ again: > DEBUG("(%x.%x): address=%04x val=0x%08x len=%d\n", > (d->devfn >> 3) & 0x1F, (d->devfn & 0x7), address, val, len); > > - if (pci_dev->need_emulate_cmd && > + if (pci_dev->emulate_cmd_mask && > ranges_overlap(address, len, PCI_COMMAND, 2)) { > if (address == PCI_COMMAND) { > - val &= 0xffff0000; > - val |= pci_default_read_config(d, PCI_COMMAND, 2); > + val &= ~pci_dev->emulate_cmd_mask; > + val |= pci_default_read_config(d, PCI_COMMAND, 2) & > + pci_dev->emulate_cmd_mask; > } else { > /* high-byte access */ > - val = pci_default_read_config(d, PCI_COMMAND+1, 1); > + val &= ~(pci_dev->emulate_cmd_mask >> 8); > + val |= pci_default_read_config(d, PCI_COMMAND+1, 1) & > + (pci_dev->emulate_cmd_mask >> 8); > } > } We should definitely be using merge_bits here, this is the sort of thing I had in mind for it: val = merge_bits(val, pci_default_read_config(d, address, len), PCI_COMMAND, pci_dev->emulate_cmd_mask); > @@ -800,10 +803,9 @@ again: > > /* dealing with virtual function device */ > snprintf(name, sizeof(name), "%sphysfn/", dir); > - if (!stat(name, &statbuf)) > - pci_dev->need_emulate_cmd = 1; > - else > - pci_dev->need_emulate_cmd = 0; > + if (!stat(name, &statbuf)) { > + pci_dev->emulate_cmd_mask = 0xffff; > + } > > dev->region_number = r; > return 0; > diff --git a/hw/device-assignment.h b/hw/device-assignment.h > index c94a730..9ead022 100644 > --- a/hw/device-assignment.h > +++ b/hw/device-assignment.h > @@ -109,7 +109,7 @@ typedef struct AssignedDevice { > void *msix_table_page; > target_phys_addr_t msix_table_addr; > int mmio_index; > - int need_emulate_cmd; > + uint32_t emulate_cmd_mask; > char *configfd_name; > QLIST_ENTRY(AssignedDevice) next; > } AssignedDevice;