From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44385) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YYTB2-00010U-JL for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:39:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YYTB1-0006SJ-8B for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:39:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41931) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YYTB1-0006SF-1Q for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:39:27 -0400 Date: Thu, 19 Mar 2015 13:19:23 +0800 From: Jason Wang Message-Id: <1426742363.5002.2@smtp.corp.redhat.com> In-Reply-To: <20150318134611-mutt-send-email-mst@redhat.com> References: <1426671309-13645-1-git-send-email-jasowang@redhat.com> <1426671309-13645-19-git-send-email-jasowang@redhat.com> <20150318134611-mutt-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Subject: Re: [Qemu-devel] [PATCH V4 18/19] pci: remove hard-coded bar size in msix_init_exclusive_bar() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: cornelia.huck@de.ibm.com, Keith Busch , Stefan Hajnoczi , qemu-devel@nongnu.org, Kevin Wolf On Wed, Mar 18, 2015 at 8:52 PM, Michael S. Tsirkin wrote: > On Wed, Mar 18, 2015 at 05:35:08PM +0800, Jason Wang wrote: >> This patch let msix_init_exclusive_bar() can accept bar_size >> parameter >> other than a hard-coded limit 4096. Then caller can specify a >> bar_size >> depends on msix entries and can use up to 2048 msix entries as PCI >> spec allows. To keep migration compatibility, 4096 is used for all >> callers and pba were start from half of bar size. >> >> Cc: Keith Busch >> Cc: Kevin Wolf >> Cc: Stefan Hajnoczi >> Cc: Michael S. Tsirkin >> Signed-off-by: Jason Wang > > Hmm this API looks strange. Caller will then have to have > msi specific knowledge. > Can't we keep the size iternal to msix.c? Looks like we can, but still need an extra parameter e.g a boolean compat_size to let msix_init_exclusive_bar() to use 4096 as bar size. > > >> --- >> hw/block/nvme.c | 2 +- >> hw/misc/ivshmem.c | 2 +- >> hw/pci/msix.c | 18 +++++++----------- >> hw/virtio/virtio-pci.c | 2 +- >> include/hw/pci/msix.h | 2 +- >> 5 files changed, 11 insertions(+), 15 deletions(-) >> >> diff --git a/hw/block/nvme.c b/hw/block/nvme.c >> index 0f3dfb9..09d7884 100644 >> --- a/hw/block/nvme.c >> +++ b/hw/block/nvme.c >> @@ -787,7 +787,7 @@ static int nvme_init(PCIDevice *pci_dev) >> pci_register_bar(&n->parent_obj, 0, >> PCI_BASE_ADDRESS_SPACE_MEMORY | >> PCI_BASE_ADDRESS_MEM_TYPE_64, >> &n->iomem); >> - msix_init_exclusive_bar(&n->parent_obj, n->num_queues, 4); >> + msix_init_exclusive_bar(&n->parent_obj, n->num_queues, 4, >> 4096); >> >> id->vid = cpu_to_le16(pci_get_word(pci_conf + PCI_VENDOR_ID)); >> id->ssvid = cpu_to_le16(pci_get_word(pci_conf + >> PCI_SUBSYSTEM_VENDOR_ID)); >> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >> index 5d272c8..3e2a2d4 100644 >> --- a/hw/misc/ivshmem.c >> +++ b/hw/misc/ivshmem.c >> @@ -631,7 +631,7 @@ static uint64_t ivshmem_get_size(IVShmemState * >> s) { >> >> static void ivshmem_setup_msi(IVShmemState * s) >> { >> - if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1)) { >> + if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1, >> 4096)) { >> IVSHMEM_DPRINTF("msix initialization failed\n"); >> exit(1); >> } >> diff --git a/hw/pci/msix.c b/hw/pci/msix.c >> index 24de260..9a1894f 100644 >> --- a/hw/pci/msix.c >> +++ b/hw/pci/msix.c >> @@ -291,33 +291,29 @@ int msix_init(struct PCIDevice *dev, unsigned >> short nentries, >> } >> >> int msix_init_exclusive_bar(PCIDevice *dev, unsigned short >> nentries, >> - uint8_t bar_nr) >> + uint8_t bar_nr, uint32_t bar_size) >> { >> int ret; >> char *name; >> + uint32_t bar_pba_offset = bar_size / 2; > > Spec says we must give BIR 4k of it's own, but for > larger BARs, using up half the BAR just for BIR seems > wasteful. I see, I will make PBA size more accurate. > > >> >> /* >> * Migration compatibility dictates that this remains a 4k >> * BAR with the vector table in the lower half and PBA in >> * the upper half. Do not use these elsewhere! >> */ > > You've left comment here where it no longer makes > any sense. Will remove this. > > >> -#define MSIX_EXCLUSIVE_BAR_SIZE 4096 >> -#define MSIX_EXCLUSIVE_BAR_TABLE_OFFSET 0 >> -#define MSIX_EXCLUSIVE_BAR_PBA_OFFSET (MSIX_EXCLUSIVE_BAR_SIZE / 2) >> -#define MSIX_EXCLUSIVE_CAP_OFFSET 0 >> - >> - if (nentries * PCI_MSIX_ENTRY_SIZE > >> MSIX_EXCLUSIVE_BAR_PBA_OFFSET) { >> + if (nentries * PCI_MSIX_ENTRY_SIZE > bar_pba_offset) { >> return -EINVAL; >> } >> >> name = g_strdup_printf("%s-msix", dev->name); >> - memory_region_init(&dev->msix_exclusive_bar, OBJECT(dev), >> name, MSIX_EXCLUSIVE_BAR_SIZE); >> + memory_region_init(&dev->msix_exclusive_bar, OBJECT(dev), >> name, bar_size); >> g_free(name); >> >> ret = msix_init(dev, nentries, &dev->msix_exclusive_bar, >> bar_nr, >> - MSIX_EXCLUSIVE_BAR_TABLE_OFFSET, >> &dev->msix_exclusive_bar, >> - bar_nr, MSIX_EXCLUSIVE_BAR_PBA_OFFSET, >> - MSIX_EXCLUSIVE_CAP_OFFSET); >> + 0, &dev->msix_exclusive_bar, >> + bar_nr, bar_pba_offset, >> + 0); >> if (ret) { >> return ret; >> } >> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c >> index 02e3ce8..4a5febb 100644 >> --- a/hw/virtio/virtio-pci.c >> +++ b/hw/virtio/virtio-pci.c >> @@ -937,7 +937,7 @@ static void >> virtio_pci_device_plugged(DeviceState *d) >> config[PCI_INTERRUPT_PIN] = 1; >> >> if (proxy->nvectors && >> - msix_init_exclusive_bar(&proxy->pci_dev, proxy->nvectors, >> 1)) { >> + msix_init_exclusive_bar(&proxy->pci_dev, proxy->nvectors, >> 1, 4096)) { >> error_report("unable to init msix vectors to %" PRIu32, >> proxy->nvectors); >> proxy->nvectors = 0; >> diff --git a/include/hw/pci/msix.h b/include/hw/pci/msix.h >> index 954d82b..43edebc 100644 >> --- a/include/hw/pci/msix.h >> +++ b/include/hw/pci/msix.h >> @@ -11,7 +11,7 @@ int msix_init(PCIDevice *dev, unsigned short >> nentries, >> unsigned table_offset, MemoryRegion *pba_bar, >> uint8_t pba_bar_nr, unsigned pba_offset, uint8_t >> cap_pos); >> int msix_init_exclusive_bar(PCIDevice *dev, unsigned short >> nentries, >> - uint8_t bar_nr); >> + uint8_t bar_nr, uint32_t bar_size); >> >> void msix_write_config(PCIDevice *dev, uint32_t address, uint32_t >> val, int len); >> >> -- >> 2.1.0