readd override_for_missing_acs_capabilities patch

Still needed by users for pci passthrough
https://forum.proxmox.com/threads/patch-add-override_for_missing_acs_capabilities-patch.23099/#post-116518
https://forum.proxmox.com/threads/proxmox-4-0-pci-passthrough-broken-in-several-ways.24178/#post-126776

I have take the last patch version from archlinux vfio kernel
https://aur.archlinux.org/packages/linux-vfio/

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>

diff --git a/Makefile b/Makefile
index 68cc345aedcc267f24234591bdc46107e43ffbe8..e0063b3bb34c0b5c4b094930609ab25354c904ae 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -233,7 +233,7 @@ ${KERNEL_SRC}/README ${KERNEL_CFG_ORG}: ${KERNELSRCTAR}
        cd ${KERNEL_SRC}; patch -p1 <../bridge-patch.diff
        #cd ${KERNEL_SRC}; patch -p1 <../bridge-forward-ipv6-neighbor-solicitation.patch
        #cd ${KERNEL_SRC}; patch -p1 <../add-empty-ndo_poll_controller-to-veth.patch
-       #cd ${KERNEL_SRC}; patch -p1 <../override_for_missing_acs_capabilities.patch
+       cd ${KERNEL_SRC}; patch -p1 <../override_for_missing_acs_capabilities.patch
        #cd ${KERNEL_SRC}; patch -p1 <../vhost-net-extend-device-allocation-to-vmalloc.patch
        cd ${KERNEL_SRC}; patch -p1 <../kvmstealtime.patch
        cd ${KERNEL_SRC}; patch -p1 <../kvm-x86-obey-KVM_X86_QUIRK_CD_NW_CLEARED-in-kvm_set_cr0.patch

diff --git a/override_for_missing_acs_capabilities.patch b/override_for_missing_acs_capabilities.patch
new file mode 100644 (file)
index 0000000..1c0b02c
--- /dev/null
+++ b/override_for_missing_acs_capabilities.patch
@@ -0,0 +1,147 @@
+diff -rupN linux-3.15.old/Documentation/kernel-parameters.txt linux-3.15/Documentation/kernel-parameters.txt
+--- linux-3.15.old/Documentation/kernel-parameters.txt 2014-06-08 15:19:54.000000000 -0300
++++ linux-3.15/Documentation/kernel-parameters.txt     2014-06-09 18:05:31.744055580 -0300
+@@ -2554,6 +2554,16 @@ bytes respectively. Such letter suffixes
+               nomsi   Do not use MSI for native PCIe PME signaling (this makes
+                       all PCIe root ports use INTx for all services).
+ 
++      pcie_acs_override =
++                      [PCIE] Override missing PCIe ACS support for:
++              downstream
++                      All downstream ports - full ACS capabilties
++              multifunction
++                      All multifunction devices - multifunction ACS subset
++              id:nnnn:nnnn
++                      Specfic device - full ACS capabilities
++                      Specified as vid:did (vendor/device ID) in hex
++
+       pcmv=           [HW,PCMCIA] BadgePAD 4
+ 
+       pd_ignore_unused
+diff -rupN linux-3.15.old/drivers/pci/quirks.c linux-3.15/drivers/pci/quirks.c
+--- linux-3.15.old/drivers/pci/quirks.c        2014-06-08 15:19:54.000000000 -0300
++++ linux-3.15/drivers/pci/quirks.c    2014-06-09 18:06:36.688743183 -0300
+@@ -3384,6 +3384,107 @@ struct pci_dev *pci_get_dma_source(struc
+       return pci_dev_get(dev);
+ }
+ 
++static bool acs_on_downstream;
++static bool acs_on_multifunction;
++
++#define NUM_ACS_IDS 16
++struct acs_on_id {
++      unsigned short vendor;
++      unsigned short device;
++};
++static struct acs_on_id acs_on_ids[NUM_ACS_IDS];
++static u8 max_acs_id;
++
++static __init int pcie_acs_override_setup(char *p)
++{
++      if (!p)
++              return -EINVAL;
++
++      while (*p) {
++              if (!strncmp(p, "downstream", 10))
++                      acs_on_downstream = true;
++              if (!strncmp(p, "multifunction", 13))
++                      acs_on_multifunction = true;
++              if (!strncmp(p, "id:", 3)) {
++                      char opt[5];
++                      int ret;
++                      long val;
++
++                      if (max_acs_id >= NUM_ACS_IDS - 1) {
++                              pr_warn("Out of PCIe ACS override slots (%d)\n",
++                                      NUM_ACS_IDS);
++                              goto next;
++                      }
++
++                      p += 3;
++                      snprintf(opt, 5, "%s", p);
++                      ret = kstrtol(opt, 16, &val);
++                      if (ret) {
++                              pr_warn("PCIe ACS ID parse error %d\n", ret);
++                              goto next;
++                      }
++                      acs_on_ids[max_acs_id].vendor = val;
++
++                      p += strcspn(p, ":");
++                      if (*p != ':') {
++                              pr_warn("PCIe ACS invalid ID\n");
++                              goto next;
++                      }
++
++                      p++;
++                      snprintf(opt, 5, "%s", p);
++                      ret = kstrtol(opt, 16, &val);
++                      if (ret) {
++                              pr_warn("PCIe ACS ID parse error %d\n", ret);
++                              goto next;
++                      }
++                      acs_on_ids[max_acs_id].device = val;
++                      max_acs_id++;
++              }
++next:
++              p += strcspn(p, ",");
++              if (*p == ',')
++                      p++;
++      }
++
++      if (acs_on_downstream || acs_on_multifunction || max_acs_id)
++              pr_warn("Warning: PCIe ACS overrides enabled; This may allow non-IOMMU protected peer-to-peer DMA\n");
++
++      return 0;
++}
++early_param("pcie_acs_override", pcie_acs_override_setup);
++
++static int pcie_acs_overrides(struct pci_dev *dev, u16 acs_flags)
++{
++      int i;
++
++      /* Never override ACS for legacy devices or devices with ACS caps */
++      if (!pci_is_pcie(dev) ||
++          pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS))
++              return -ENOTTY;
++
++      for (i = 0; i < max_acs_id; i++)
++              if (acs_on_ids[i].vendor == dev->vendor &&
++                  acs_on_ids[i].device == dev->device)
++                      return 1;
++
++      switch (pci_pcie_type(dev)) {
++      case PCI_EXP_TYPE_DOWNSTREAM:
++      case PCI_EXP_TYPE_ROOT_PORT:
++              if (acs_on_downstream)
++                      return 1;
++              break;
++      case PCI_EXP_TYPE_ENDPOINT:
++      case PCI_EXP_TYPE_UPSTREAM:
++      case PCI_EXP_TYPE_LEG_END:
++      case PCI_EXP_TYPE_RC_END:
++              if (acs_on_multifunction && dev->multifunction)
++                      return 1;
++      }
++
++      return -ENOTTY;
++}
++
+ /*
+  * AMD has indicated that the devices below do not support peer-to-peer
+  * in any system where they are found in the southbridge with an AMD
+@@ -3483,6 +3584,7 @@ static int pci_quirk_intel_pch_acs(struc
+       return acs_flags & ~flags ? 0 : 1;
+ }
+ 
++
+ static const struct pci_dev_acs_enabled {
+       u16 vendor;
+       u16 device;
+@@ -3495,6 +3597,7 @@ static const struct pci_dev_acs_enabled
+       { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_intel_pch_acs },
+       { 0x19a2, 0x710, pci_quirk_mf_endpoint_acs }, /* Emulex BE3-R */
+       { 0x10df, 0x720, pci_quirk_mf_endpoint_acs }, /* Emulex Skyhawk-R */
++      { PCI_ANY_ID, PCI_ANY_ID, pcie_acs_overrides },
+       { 0 }
+ };
+