unmodified_drivers: misc changes for xenlinux PVonHVM drivers

This series of patches is used since some time to compile the PVonHVM drivers against the forward ported xenlinux tree used in openSuSE.

Please review and apply.

Changes:
unmodified_drivers: hide xen_cpuid_base() in version 2.6.38+
unmodified_drivers: add pfn_is_ram helper for kdump
unmodified_drivers: use upstream sync_bitops if available
unmodified_drivers: compile vcd.c into blkfront if available

 unmodified_drivers/linux-2.6/blkfront/Kbuild                      |    1 
 unmodified_drivers/linux-2.6/compat-include/xen/platform-compat.h |   10 +++
 unmodified_drivers/linux-2.6/platform-pci/platform-pci.c          |   31 ++++++++++
 3 files changed, 42 insertions(+)

# HG changeset patch
# User Olaf Hering <[email protected]>
# Date 1331883705 -3600
# Node ID 5504366919926f8a2d6fc7fdc392e6218ae6c702 # Parent 1b68427875f7ffe3025ea13c7f6e8cf71ce54769
unmodified_drivers: hide xen_cpuid_base() in version 2.6.38+

Allow compilation of PVonHVM drivers with forward-ported xenlinux sources in openSuSE 12.1. xen_cpuid_base() is now in mainline, the copy in the xen tree leads to a compilation error. The current state leads to a compile error:

/usr/src/packages/BUILD/xen-4.2.24547/non-dbg/obj/default/platform-pci/platform-pci.c:121: error: redefinition of 'xen_cpuid_base' /usr/src/linux-3.0.13-0.11/arch/x86/include/asm/xen/hypervisor.h:43: error: previous definition of 'xen_cpuid_base' was here

The reason is that the kernel sources are searched before the xen sources for asm/hypervisor.h:

/usr/src/linux-3.0.13-0.11/arch/x86/include/asm/hypervisor.h /usr/src/packages/BUILD/xen-4.2.24547/non-dbg/obj/default/include/asm/hypervisor.h

diff -r 1b68427875f7 -r 550436691992 unmodified_drivers/linux-2.6/platform-pci/platform-pci.c
@@ -118,6 +118,7 @@ unsigned long alloc_xen_mmio(unsigned lo
 
 #ifndef __ia64__
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,38)
 static uint32_t xen_cpuid_base(void)
 {
 	uint32_t base, eax, ebx, ecx, edx;

@@ -136,6 +137,7 @@ static uint32_t xen_cpuid_base(void)
 
 	return 0;
 }
+#endif
 
 static int init_hypercall_stubs(void)
 {

# HG changeset patch
# User Olaf Hering <[email protected]>
# Date 1331883706 -3600
# Node ID dacdcaaf113263ee748bef99d175b1b7e7013be5 # Parent 5504366919926f8a2d6fc7fdc392e6218ae6c702
unmodified_drivers: add pfn_is_ram helper for kdump

Register pfn_is_ram helper speed up reading /proc/vmcore in the kdump kernel. It is compiled only if the kernel source is recent enough to have the pfn_is_ram helper (v3.0-rc1, commit 997c136f518c5debd63847e78e2a8694f56dcf90).

diff -r 550436691992 -r dacdcaaf1132 unmodified_drivers/linux-2.6/platform-pci/platform-pci.c
@@ -351,6 +351,32 @@ static int check_platform_magic(struct d
 	return -ENODEV;
 }
 
+#if defined(HAVE_OLDMEM_PFN_IS_RAM)
+static int xen_oldmem_pfn_is_ram(unsigned long pfn)
+{
+	struct xen_hvm_get_mem_type a;
+	int ret;
+
+	a.domid = DOMID_SELF;
+	a.pfn = pfn;
+	if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a))
+		return -ENXIO;
+
+	switch (a.mem_type) {
+		case HVMMEM_mmio_dm:
+			ret = 0;
+			break;
+		case HVMMEM_ram_rw:
+		case HVMMEM_ram_ro:
+		default:
+			ret = 1;
+			break;
+	}
+
+	return ret;
+}
+#endif
+
 static int __devinit platform_pci_init(struct pci_dev *pdev,
 				       const struct pci_device_id *ent)
 {

@@ -419,6 +445,9 @@ static int __devinit platform_pci_init(s
 	if ((ret = xen_panic_handler_init()))
 		goto out;
 
+#if defined(HAVE_OLDMEM_PFN_IS_RAM)
+	register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram);
+#endif
  out:
 	if (ret) {
 		pci_release_region(pdev, 0);

# HG changeset patch
# User Olaf Hering <[email protected]>
# Date 1331883707 -3600
# Node ID d721480672b9686011cef0965cefd81a969277b0 # Parent dacdcaaf113263ee748bef99d175b1b7e7013be5
unmodified_drivers: use upstream sync_bitops if available

The forward ported xenlinux sources in openSuSE 12.2 were switched from the old synch_bitops to the sync_bitops since kernel version 3.3. Add compat macros to use either old or new helpers depending on used kernel source version.

diff -r dacdcaaf1132 -r d721480672b9 unmodified_drivers/linux-2.6/compat-include/xen/platform-compat.h
@@ -161,4 +161,14 @@ typedef irqreturn_t (*irq_handler_t)(int
 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
 #endif
 
+#ifdef sync_test_bit
+#define synch_change_bit		sync_change_bit
+#define synch_clear_bit			sync_clear_bit
+#define synch_set_bit			sync_set_bit
+#define synch_test_and_change_bit	sync_test_and_change_bit
+#define synch_test_and_clear_bit	sync_test_and_clear_bit
+#define synch_test_and_set_bit		sync_test_and_set_bit
+#define synch_test_bit			sync_test_bit
 #endif
+
+#endif

# HG changeset patch
# User Olaf Hering <[email protected]>
# Date 1331883708 -3600
# Node ID 321e3ada9b40a0b164ac617f26d254fc3354c024 # Parent d721480672b9686011cef0965cefd81a969277b0
unmodified_drivers: compile vcd.c into blkfront if available

The forward ported xenlinux sources in openSuSE have a PV CDROM driver since a long time. Detect the presence of this driver and compile it into the xen_vbd module.

diff -r d721480672b9 -r 321e3ada9b40 unmodified_drivers/linux-2.6/blkfront/Kbuild
@@ -3,3 +3,4 @@ include $(M)/overrides.mk
 obj-m += xen-vbd.o
 
 xen-vbd-objs := blkfront.o vbd.o
+xen-vbd-objs += $(patsubst %.c,%.o,$(notdir $(wildcard $(src)/vcd.c)))