| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1519939897-14596-1-git-send-email-karahmed@amazon.de>
Date: Thu, 1 Mar 2018 22:31:36 +0100
From: KarimAllah Ahmed <karahmed@...zon.de>
To: linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org
Cc: KarimAllah Ahmed <karahmed@...zon.de>,
Bjorn Helgaas <bhelgaas@...gle.com>
Subject: [PATCH v3 1/2] PCI/IOV: Store more data about VFs into the SRIOV struct
Store more data about PCI VFs into the SRIOV to avoid reading them from the
config space of all the PCI VFs. This is specially a useful optimization
when bringing up thousands of VFs.
Cc: Bjorn Helgaas <bhelgaas@...gle.com>
Cc: linux-pci@...r.kernel.org
Cc: linux-kernel@...r.kernel.org
Signed-off-by: KarimAllah Ahmed <karahmed@...zon.de>
---
v2 -> v3:
* Update changelog
* Move the call to pci_read_vf_config_common a bit later and use standard
pci_read_config*.
* Update whitespace.
* Move the using barsz into its own patch.
* Added a comment about the usage of subsystem vendor id, subsystem id, and
class revision.
* Make sure virtfn->is_virtfn is set before calling into pci_setup_device.
v1 -> v2:
* Rebase on latest + remove dependency on a non-upstream patch.
drivers/pci/iov.c | 48 +++++++++++++++++++++++++++++++++++++++++-------
drivers/pci/pci.h | 5 +++++
drivers/pci/probe.c | 18 ++++++++++++++----
3 files changed, 60 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index 677924a..10291a0 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -114,6 +114,36 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
}
+static void pci_read_vf_config_common(struct pci_dev *virtfn)
+{
+ struct pci_dev *physfn = virtfn->physfn;
+
+ BUG_ON(!virtfn->is_virtfn || physfn->is_virtfn);
+
+ /*
+ * Per PCIe r4.0, sec 9.3.4.1.5, the value reported in the VF maybe
+ * different than the value reported in the PF. We assume here that all
+ * VFs would report the same revision ID.
+ */
+ pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
+ &physfn->sriov->class);
+ /*
+ * Per PCIe r4.0, sec 9.3.4.1.13, the field in the PF and the
+ * associated VFs must return the same value.
+ */
+ pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
+ &physfn->sriov->subsystem_vendor);
+ /*
+ * Per PCIe r4.0, sec 9.3.4.1.14, the value reported in the VF maybe
+ * different than the value reported in the PF. We assume here that all
+ * VFs would report the same subsystem ID.
+ */
+ pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
+ &physfn->sriov->subsystem_device);
+ pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
+ &physfn->sriov->hdr_type);
+}
+
int pci_iov_add_virtfn(struct pci_dev *dev, int id)
{
int i;
@@ -134,15 +164,18 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
goto failed0;
virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
+ virtfn->is_virtfn = 1;
+ virtfn->physfn = pci_dev_get(dev);
+ if (id == 0)
+ /* virtfn->{devfn,bus,is_virtfn,physfn} have to be initialized */
+ pci_read_vf_config_common(virtfn);
virtfn->vendor = dev->vendor;
virtfn->device = iov->vf_device;
rc = pci_setup_device(virtfn);
if (rc)
- goto failed0;
+ goto failed1;
virtfn->dev.parent = dev->dev.parent;
- virtfn->physfn = pci_dev_get(dev);
- virtfn->is_virtfn = 1;
virtfn->multifunction = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
@@ -163,10 +196,10 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
sprintf(buf, "virtfn%u", id);
rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
if (rc)
- goto failed1;
+ goto failed2;
rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
if (rc)
- goto failed2;
+ goto failed3;
kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
@@ -174,11 +207,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
return 0;
-failed2:
+failed3:
sysfs_remove_link(&dev->dev.kobj, buf);
+failed2:
+ pci_stop_and_remove_bus_device(virtfn);
failed1:
pci_dev_put(dev);
- pci_stop_and_remove_bus_device(virtfn);
failed0:
virtfn_remove_bus(dev->bus, bus);
failed:
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index fcd8191..17e6688 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -271,6 +271,11 @@ struct pci_sriov {
u16 driver_max_VFs; /* Max num VFs driver supports */
struct pci_dev *dev; /* Lowest numbered PF */
struct pci_dev *self; /* This PF */
+ u8 hdr_type; /* VF header type */
+ u32 class; /* VF device */
+ u16 device; /* VF device */
+ u16 subsystem_vendor; /* VF subsystem vendor */
+ u16 subsystem_device; /* VF subsystem device */
resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */
bool drivers_autoprobe; /* Auto probing of VFs by driver */
};
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ef53774..a96837e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1454,7 +1454,9 @@ int pci_setup_device(struct pci_dev *dev)
struct pci_bus_region region;
struct resource *res;
- if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
+ if (dev->is_virtfn)
+ hdr_type = dev->physfn->sriov->hdr_type;
+ else if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
return -EIO;
dev->sysdata = dev->bus->sysdata;
@@ -1477,7 +1479,10 @@ int pci_setup_device(struct pci_dev *dev)
dev->bus->number, PCI_SLOT(dev->devfn),
PCI_FUNC(dev->devfn));
- pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
+ if (dev->is_virtfn)
+ class = dev->physfn->sriov->class;
+ else
+ pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
dev->revision = class & 0xff;
dev->class = class >> 8; /* upper 3 bytes */
@@ -1517,8 +1522,13 @@ int pci_setup_device(struct pci_dev *dev)
goto bad;
pci_read_irq(dev);
pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
- pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
- pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
+ if (dev->is_virtfn) {
+ dev->subsystem_vendor = dev->physfn->sriov->subsystem_vendor;
+ dev->subsystem_device = dev->physfn->sriov->subsystem_device;
+ } else {
+ pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
+ pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
+ }
/*
* Do the ugly legacy mode stuff here rather than broken chip
--
2.7.4
Powered by blists - more mailing lists