[PATCH v5 8/9] Revert "xen/arm: Add cmdline boot option "pci-passthrough = <boolean>""

[Stewart Hildebrand <stewart.hildebrand@xxxxxxx>]

From: Rahul Singh <rahul.singh@xxxxxxx>

This enables us to use IOMMU + PCI in dom0 without having to specify
"pci-passthrough=yes".

This reverts commit 15517ed61f55be6039aedcc99720ee07c772ed44.
---
v4->v5:
* new patch
---
 docs/misc/xen-command-line.pandoc |  7 -------
 xen/arch/arm/include/asm/pci.h    | 12 ------------
 xen/arch/arm/pci/pci.c            | 12 ------------
 xen/arch/x86/include/asm/pci.h    |  6 ------
 xen/drivers/pci/physdev.c         |  6 ------
 5 files changed, 43 deletions(-)

diff --git a/docs/misc/xen-command-line.pandoc 
b/docs/misc/xen-command-line.pandoc
index 604650aaeeef..bd2f1070c445 100644
--- a/docs/misc/xen-command-line.pandoc
+++ b/docs/misc/xen-command-line.pandoc
@@ -1955,13 +1955,6 @@ All numbers specified must be hexadecimal ones.
 
 This option can be specified more than once (up to 8 times at present).
 
-### pci-passthrough (arm)
-> `= <boolean>`
-
-> Default: `false`
-
-Flag to enable or disable support for PCI passthrough
-
 ### pcid (x86)
 > `= <boolean> | xpti=<bool>`
 
diff --git a/xen/arch/arm/include/asm/pci.h b/xen/arch/arm/include/asm/pci.h
index 8cb46f6b7185..e14013901469 100644
--- a/xen/arch/arm/include/asm/pci.h
+++ b/xen/arch/arm/include/asm/pci.h
@@ -21,8 +21,6 @@
 
 #define pci_to_dev(pcidev) (&(pcidev)->arch.dev)
 
-extern bool pci_passthrough_enabled;
-
 /* Arch pci dev struct */
 struct arch_pci_dev {
     struct device dev;
@@ -111,11 +109,6 @@ pci_find_host_bridge_node(const struct pci_dev *pdev);
 int pci_get_host_bridge_segment(const struct dt_device_node *node,
                                 uint16_t *segment);
 
-static always_inline bool is_pci_passthrough_enabled(void)
-{
-    return pci_passthrough_enabled;
-}
-
 void arch_pci_init_pdev(struct pci_dev *pdev);
 
 int pci_get_new_domain_nr(void);
@@ -132,11 +125,6 @@ bool pci_check_bar(const struct pci_dev *pdev, mfn_t 
start, mfn_t end);
 
 struct arch_pci_dev { };
 
-static always_inline bool is_pci_passthrough_enabled(void)
-{
-    return false;
-}
-
 struct pci_dev;
 
 static inline void arch_pci_init_pdev(struct pci_dev *pdev) {}
diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
index 78b97beaef12..e0a63242ab21 100644
--- a/xen/arch/arm/pci/pci.c
+++ b/xen/arch/arm/pci/pci.c
@@ -16,7 +16,6 @@
 #include <xen/device_tree.h>
 #include <xen/errno.h>
 #include <xen/init.h>
-#include <xen/param.h>
 #include <xen/pci.h>
 
 /*
@@ -75,19 +74,8 @@ static int __init acpi_pci_init(void)
 }
 #endif
 
-/* By default pci passthrough is disabled. */
-bool __read_mostly pci_passthrough_enabled;
-boolean_param("pci-passthrough", pci_passthrough_enabled);
-
 static int __init pci_init(void)
 {
-    /*
-     * Enable PCI passthrough when has been enabled explicitly
-     * (pci-passthrough=on).
-     */
-    if ( !pci_passthrough_enabled )
-        return 0;
-
     pci_segments_init();
 
     if ( acpi_disabled )
diff --git a/xen/arch/x86/include/asm/pci.h b/xen/arch/x86/include/asm/pci.h
index f4a58c8acf13..3eb6fb8edf30 100644
--- a/xen/arch/x86/include/asm/pci.h
+++ b/xen/arch/x86/include/asm/pci.h
@@ -49,12 +49,6 @@ bool_t pci_ro_mmcfg_decode(unsigned long mfn, unsigned int 
*seg,
 extern int pci_mmcfg_config_num;
 extern struct acpi_mcfg_allocation *pci_mmcfg_config;
 
-/* Unlike ARM, PCI passthrough is always enabled for x86. */
-static always_inline bool is_pci_passthrough_enabled(void)
-{
-    return true;
-}
-
 void arch_pci_init_pdev(struct pci_dev *pdev);
 
 static inline bool pci_check_bar(const struct pci_dev *pdev,
diff --git a/xen/drivers/pci/physdev.c b/xen/drivers/pci/physdev.c
index 42db3e6d133c..4f3e1a96c0fd 100644
--- a/xen/drivers/pci/physdev.c
+++ b/xen/drivers/pci/physdev.c
@@ -18,9 +18,6 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) 
arg)
         struct pci_dev_info pdev_info;
         nodeid_t node = NUMA_NO_NODE;
 
-        if ( !is_pci_passthrough_enabled() )
-            return -EOPNOTSUPP;
-
         ret = -EFAULT;
         if ( copy_from_guest(&add, arg, 1) != 0 )
             break;
@@ -56,9 +53,6 @@ ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) 
arg)
     case PHYSDEVOP_pci_device_remove: {
         struct physdev_pci_device dev;
 
-        if ( !is_pci_passthrough_enabled() )
-            return -EOPNOTSUPP;
-
         ret = -EFAULT;
         if ( copy_from_guest(&dev, arg, 1) != 0 )
             break;
-- 
2.42.0