[PATCH 0/6] Xen patches for Linux 3.7

[PATCH 0/6] Xen patches for Linux 3.7

[Stefano Stabellini]

Hi Konrad,
the followings are the patches that I am proposing for Linux 3.7.
I am leaving out the bulk of the ARM patches for the moment.


Stefano Stabellini (6):
      xen/events: fix unmask_evtchn for PV on HVM guests
      xen: missing includes
      xen: update xen_add_to_physmap interface
      xen: Introduce xen_pfn_t for pfn and mfn types
      xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
      xen: allow privcmd for HVM guests

 arch/ia64/include/asm/xen/interface.h      |    7 ++++++-
 arch/x86/include/asm/xen/interface.h       |    7 +++++++
 arch/x86/xen/mmu.c                         |    3 +++
 drivers/tty/hvc/hvc_xen.c                  |    2 ++
 drivers/xen/events.c                       |   18 +++++++++++++++---
 drivers/xen/grant-table.c                  |    1 +
 drivers/xen/privcmd.c                      |    4 ----
 drivers/xen/xenbus/xenbus_probe_frontend.c |    1 +
 include/xen/interface/grant_table.h        |    4 ++--
 include/xen/interface/memory.h             |    9 ++++++---
 include/xen/interface/platform.h           |    4 ++--
 include/xen/interface/xen.h                |    7 +++----
 include/xen/privcmd.h                      |    3 +--
 13 files changed, 49 insertions(+), 21 deletions(-)


A git branch based on v3.6-rc2 is available here:

git://xenbits.xen.org/people/sstabellini/linux-pvhvm.git for_upstream_3.7

Cheers,

Stefano

[PATCH 1/6] xen/events: fix unmask_evtchn for PV on HVM guests

[Stefano Stabellini]

When unmask_evtchn is called, if we already have an event pending, we
just set evtchn_pending_sel waiting for local_irq_enable to be called.
That is because PV guests set the irq_enable pvops to
xen_irq_enable_direct in xen_setup_vcpu_info_placement:
xen_irq_enable_direct is implemented in assembly in
arch/x86/xen/xen-asm.S and call xen_force_evtchn_callback if
XEN_vcpu_info_pending is set.

However HVM guests (and ARM guests) do not change or do not have the
irq_enable pvop, so evtchn_unmask cannot work properly for them.

Considering that having the pending_irq bit set when unmask_evtchn is
called is not very common, and it is simpler to keep the
native_irq_enable implementation for HVM guests (and ARM guests), the
best thing to do is just use the EVTCHNOP_unmask hypercall (Xen
re-injects pending events in response).

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 drivers/xen/events.c |   17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 7595581..36bf17d 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -373,11 +373,22 @@ static void unmask_evtchn(int port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	unsigned int cpu = get_cpu();
+	int do_hypercall = 0, evtchn_pending = 0;
 
 	BUG_ON(!irqs_disabled());
 
-	/* Slow path (hypercall) if this is a non-local port. */
-	if (unlikely(cpu != cpu_from_evtchn(port))) {
+	if (unlikely((cpu != cpu_from_evtchn(port))))
+		do_hypercall = 1;
+	else
+		evtchn_pending = sync_test_bit(port, &s->evtchn_pending[0]);
+
+	if (unlikely(evtchn_pending && xen_hvm_domain()))
+		do_hypercall = 1;
+
+	/* Slow path (hypercall) if this is a non-local port or if this is
+	 * an hvm domain and an event is pending (hvm domains don't have
+	 * their own implementation of irq_enable). */
+	if (do_hypercall) {
 		struct evtchn_unmask unmask = { .port = port };
 		(void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
 	} else {
@@ -390,7 +401,7 @@ static void unmask_evtchn(int port)
 		 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
 		 * the interrupt edge' if the channel is masked.
 		 */
-		if (sync_test_bit(port, &s->evtchn_pending[0]) &&
+		if (evtchn_pending &&
 		    !sync_test_and_set_bit(port / BITS_PER_LONG,
 					   &vcpu_info->evtchn_pending_sel))
 			vcpu_info->evtchn_upcall_pending = 1;
-- 
1.7.2.5

[PATCH 2/6] xen: missing includes

[Stefano Stabellini]

Changes in v3:
- add missing pvclock-abi.h include to ia64 header files.

Changes in v2:
- remove pvclock hack;
- remove include linux/types.h from xen/interface/xen.h.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 arch/ia64/include/asm/xen/interface.h      |    2 ++
 arch/x86/include/asm/xen/interface.h       |    2 ++
 drivers/tty/hvc/hvc_xen.c                  |    2 ++
 drivers/xen/grant-table.c                  |    1 +
 drivers/xen/xenbus/xenbus_probe_frontend.c |    1 +
 include/xen/interface/xen.h                |    1 -
 include/xen/privcmd.h                      |    1 +
 7 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/arch/ia64/include/asm/xen/interface.h b/arch/ia64/include/asm/xen/interface.h
index 09d5f7f..ee9cad6 100644
--- a/arch/ia64/include/asm/xen/interface.h
+++ b/arch/ia64/include/asm/xen/interface.h
@@ -265,6 +265,8 @@ typedef struct xen_callback xen_callback_t;
 
 #endif /* !__ASSEMBLY__ */
 
+#include <asm/pvclock-abi.h>
+
 /* Size of the shared_info area (this is not related to page size).  */
 #define XSI_SHIFT			14
 #define XSI_SIZE			(1 << XSI_SHIFT)
diff --git a/arch/x86/include/asm/xen/interface.h b/arch/x86/include/asm/xen/interface.h
index cbf0c9d..a93db16 100644
--- a/arch/x86/include/asm/xen/interface.h
+++ b/arch/x86/include/asm/xen/interface.h
@@ -121,6 +121,8 @@ struct arch_shared_info {
 #include "interface_64.h"
 #endif
 
+#include <asm/pvclock-abi.h>
+
 #ifndef __ASSEMBLY__
 /*
  * The following is all CPU context. Note that the fpu_ctxt block is filled
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 1e456dc..2944ff8 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -21,6 +21,7 @@
 #include <linux/console.h>
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/irq.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/list.h>
@@ -35,6 +36,7 @@
 #include <xen/page.h>
 #include <xen/events.h>
 #include <xen/interface/io/console.h>
+#include <xen/interface/sched.h>
 #include <xen/hvc-console.h>
 #include <xen/xenbus.h>
 
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 0bfc1ef..1d0d95e 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -47,6 +47,7 @@
 #include <xen/interface/memory.h>
 #include <xen/hvc-console.h>
 #include <asm/xen/hypercall.h>
+#include <asm/xen/interface.h>
 
 #include <asm/pgtable.h>
 #include <asm/sync_bitops.h>
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index a31b54d..3159a37 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -21,6 +21,7 @@
 #include <xen/xenbus.h>
 #include <xen/events.h>
 #include <xen/page.h>
+#include <xen/xen.h>
 
 #include <xen/platform_pci.h>
 
diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h
index 0801468..6e75dea 100644
--- a/include/xen/interface/xen.h
+++ b/include/xen/interface/xen.h
@@ -10,7 +10,6 @@
 #define __XEN_PUBLIC_XEN_H__
 
 #include <asm/xen/interface.h>
-#include <asm/pvclock-abi.h>
 
 /*
  * XEN "SYSTEM CALLS" (a.k.a. HYPERCALLS).
diff --git a/include/xen/privcmd.h b/include/xen/privcmd.h
index 17857fb..4d58881 100644
--- a/include/xen/privcmd.h
+++ b/include/xen/privcmd.h
@@ -35,6 +35,7 @@
 
 #include <linux/types.h>
 #include <linux/compiler.h>
+#include <xen/interface/xen.h>
 
 typedef unsigned long xen_pfn_t;
 
-- 
1.7.2.5

[PATCH 3/6] xen: update xen_add_to_physmap interface

[Stefano Stabellini]

Update struct xen_add_to_physmap to be in sync with Xen's version of the
structure.
The size field was introduced by:

changeset:   24164:707d27fe03e7
user:        Jean Guyader <jean.guyader@eu.citrix.com>
date:        Fri Nov 18 13:42:08 2011 +0000
summary:     mm: New XENMEM space, XENMAPSPACE_gmfn_range

According to the comment:

"This new field .size is located in the 16 bits padding between .domid
and .space in struct xen_add_to_physmap to stay compatible with older
versions."

Changes in v2:

- remove erroneous comment in the commit message.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 include/xen/interface/memory.h |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h
index eac3ce1..8d4efc1 100644
--- a/include/xen/interface/memory.h
+++ b/include/xen/interface/memory.h
@@ -163,6 +163,9 @@ struct xen_add_to_physmap {
     /* Which domain to change the mapping for. */
     domid_t domid;
 
+    /* Number of pages to go through for gmfn_range */
+    uint16_t    size;
+
     /* Source mapping space. */
 #define XENMAPSPACE_shared_info 0 /* shared info page */
 #define XENMAPSPACE_grant_table 1 /* grant table page */
-- 
1.7.2.5

[PATCH 4/6] xen: Introduce xen_pfn_t for pfn and mfn types

[Stefano Stabellini]

All the original Xen headers have xen_pfn_t as mfn and pfn type, however
when they have been imported in Linux, xen_pfn_t has been replaced with
unsigned long. That might work for x86 and ia64 but it does not for arm.
Bring back xen_pfn_t and let each architecture define xen_pfn_t as they
see fit.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/ia64/include/asm/xen/interface.h |    5 ++++-
 arch/x86/include/asm/xen/interface.h  |    5 +++++
 include/xen/interface/grant_table.h   |    4 ++--
 include/xen/interface/memory.h        |    6 +++---
 include/xen/interface/platform.h      |    4 ++--
 include/xen/interface/xen.h           |    6 +++---
 include/xen/privcmd.h                 |    2 --
 7 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/arch/ia64/include/asm/xen/interface.h b/arch/ia64/include/asm/xen/interface.h
index ee9cad6..3d52a5b 100644
--- a/arch/ia64/include/asm/xen/interface.h
+++ b/arch/ia64/include/asm/xen/interface.h
@@ -67,6 +67,10 @@
 #define set_xen_guest_handle(hnd, val)	do { (hnd).p = val; } while (0)
 
 #ifndef __ASSEMBLY__
+/* Explicitly size integers that represent pfns in the public interface
+ * with Xen so that we could have one ABI that works for 32 and 64 bit
+ * guests. */
+typedef unsigned long xen_pfn_t;
 /* Guest handles for primitive C types. */
 __DEFINE_GUEST_HANDLE(uchar, unsigned char);
 __DEFINE_GUEST_HANDLE(uint, unsigned int);
@@ -79,7 +83,6 @@ DEFINE_GUEST_HANDLE(void);
 DEFINE_GUEST_HANDLE(uint64_t);
 DEFINE_GUEST_HANDLE(uint32_t);
 
-typedef unsigned long xen_pfn_t;
 DEFINE_GUEST_HANDLE(xen_pfn_t);
 #define PRI_xen_pfn	"lx"
 #endif
diff --git a/arch/x86/include/asm/xen/interface.h b/arch/x86/include/asm/xen/interface.h
index a93db16..555f94d 100644
--- a/arch/x86/include/asm/xen/interface.h
+++ b/arch/x86/include/asm/xen/interface.h
@@ -47,6 +47,10 @@
 #endif
 
 #ifndef __ASSEMBLY__
+/* Explicitly size integers that represent pfns in the public interface
+ * with Xen so that on ARM we can have one ABI that works for 32 and 64
+ * bit guests. */
+typedef unsigned long xen_pfn_t;
 /* Guest handles for primitive C types. */
 __DEFINE_GUEST_HANDLE(uchar, unsigned char);
 __DEFINE_GUEST_HANDLE(uint,  unsigned int);
@@ -57,6 +61,7 @@ DEFINE_GUEST_HANDLE(long);
 DEFINE_GUEST_HANDLE(void);
 DEFINE_GUEST_HANDLE(uint64_t);
 DEFINE_GUEST_HANDLE(uint32_t);
+DEFINE_GUEST_HANDLE(xen_pfn_t);
 #endif
 
 #ifndef HYPERVISOR_VIRT_START
diff --git a/include/xen/interface/grant_table.h b/include/xen/interface/grant_table.h
index a17d844..7da811b 100644
--- a/include/xen/interface/grant_table.h
+++ b/include/xen/interface/grant_table.h
@@ -338,7 +338,7 @@ DEFINE_GUEST_HANDLE_STRUCT(gnttab_dump_table);
 #define GNTTABOP_transfer                4
 struct gnttab_transfer {
     /* IN parameters. */
-    unsigned long mfn;
+    xen_pfn_t mfn;
     domid_t       domid;
     grant_ref_t   ref;
     /* OUT parameters. */
@@ -375,7 +375,7 @@ struct gnttab_copy {
 	struct {
 		union {
 			grant_ref_t ref;
-			unsigned long   gmfn;
+			xen_pfn_t   gmfn;
 		} u;
 		domid_t  domid;
 		uint16_t offset;
diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h
index 8d4efc1..d8e33a9 100644
--- a/include/xen/interface/memory.h
+++ b/include/xen/interface/memory.h
@@ -31,7 +31,7 @@ struct xen_memory_reservation {
      *   OUT: GMFN bases of extents that were allocated
      *   (NB. This command also updates the mach_to_phys translation table)
      */
-    GUEST_HANDLE(ulong) extent_start;
+    GUEST_HANDLE(xen_pfn_t) extent_start;
 
     /* Number of extents, and size/alignment of each (2^extent_order pages). */
     unsigned long  nr_extents;
@@ -130,7 +130,7 @@ struct xen_machphys_mfn_list {
      * any large discontiguities in the machine address space, 2MB gaps in
      * the machphys table will be represented by an MFN base of zero.
      */
-    GUEST_HANDLE(ulong) extent_start;
+    GUEST_HANDLE(xen_pfn_t) extent_start;
 
     /*
      * Number of extents written to the above array. This will be smaller
@@ -175,7 +175,7 @@ struct xen_add_to_physmap {
     unsigned long idx;
 
     /* GPFN where the source mapping page should appear. */
-    unsigned long gpfn;
+    xen_pfn_t gpfn;
 };
 DEFINE_GUEST_HANDLE_STRUCT(xen_add_to_physmap);
 
diff --git a/include/xen/interface/platform.h b/include/xen/interface/platform.h
index 61fa661..a3275a8 100644
--- a/include/xen/interface/platform.h
+++ b/include/xen/interface/platform.h
@@ -54,7 +54,7 @@ DEFINE_GUEST_HANDLE_STRUCT(xenpf_settime_t);
 #define XENPF_add_memtype         31
 struct xenpf_add_memtype {
 	/* IN variables. */
-	unsigned long mfn;
+	xen_pfn_t mfn;
 	uint64_t nr_mfns;
 	uint32_t type;
 	/* OUT variables. */
@@ -84,7 +84,7 @@ struct xenpf_read_memtype {
 	/* IN variables. */
 	uint32_t reg;
 	/* OUT variables. */
-	unsigned long mfn;
+	xen_pfn_t mfn;
 	uint64_t nr_mfns;
 	uint32_t type;
 };
diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h
index 6e75dea..1e0df6b 100644
--- a/include/xen/interface/xen.h
+++ b/include/xen/interface/xen.h
@@ -189,7 +189,7 @@ struct mmuext_op {
 	unsigned int cmd;
 	union {
 		/* [UN]PIN_TABLE, NEW_BASEPTR, NEW_USER_BASEPTR */
-		unsigned long mfn;
+		xen_pfn_t mfn;
 		/* INVLPG_LOCAL, INVLPG_ALL, SET_LDT */
 		unsigned long linear_addr;
 	} arg1;
@@ -429,11 +429,11 @@ struct start_info {
 	unsigned long nr_pages;     /* Total pages allocated to this domain.  */
 	unsigned long shared_info;  /* MACHINE address of shared info struct. */
 	uint32_t flags;             /* SIF_xxx flags.                         */
-	unsigned long store_mfn;    /* MACHINE page number of shared page.    */
+	xen_pfn_t store_mfn;        /* MACHINE page number of shared page.    */
 	uint32_t store_evtchn;      /* Event channel for store communication. */
 	union {
 		struct {
-			unsigned long mfn;  /* MACHINE page number of console page.   */
+			xen_pfn_t mfn;      /* MACHINE page number of console page.   */
 			uint32_t  evtchn;   /* Event channel for console page.        */
 		} domU;
 		struct {
diff --git a/include/xen/privcmd.h b/include/xen/privcmd.h
index 4d58881..45c1aa1 100644
--- a/include/xen/privcmd.h
+++ b/include/xen/privcmd.h
@@ -37,8 +37,6 @@
 #include <linux/compiler.h>
 #include <xen/interface/xen.h>
 
-typedef unsigned long xen_pfn_t;
-
 struct privcmd_hypercall {
 	__u64 op;
 	__u64 arg[5];
-- 
1.7.2.5

[PATCH 5/6] xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST

[Stefano Stabellini]

Reset the IRQ_NOAUTOEN and IRQ_NOREQUEST flags that are enabled by
default on ARM. If IRQ_NOAUTOEN is set, __setup_irq doesn't call
irq_startup, that is responsible for calling irq_unmask at startup time.
As a result event channels remain masked.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 drivers/xen/events.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 36bf17d..c60d162 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -842,6 +842,7 @@ int bind_evtchn_to_irq(unsigned int evtchn)
 		struct irq_info *info = info_for_irq(irq);
 		WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
 	}
+	irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
 
 out:
 	mutex_unlock(&irq_mapping_update_lock);
-- 
1.7.2.5

[PATCH 6/6] xen: allow privcmd for HVM guests

[Stefano Stabellini]

This patch removes the "return -ENOSYS" for auto_translated_physmap
guests from privcmd_mmap, thus it allows ARM guests to issue privcmd
mmap calls. However privcmd mmap calls are still going to fail for HVM
and hybrid guests on x86 because the xen_remap_domain_mfn_range
implementation is currently PV only.

Changes in v2:

- better commit message;
- return -EINVAL from xen_remap_domain_mfn_range if
  auto_translated_physmap.


Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/xen/mmu.c    |    3 +++
 drivers/xen/privcmd.c |    4 ----
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index b65a761..2a1ee7b 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -2337,6 +2337,9 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
 	unsigned long range;
 	int err = 0;
 
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return -EINVAL;
+
 	prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP);
 
 	BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_RESERVED | VM_IO)) ==
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index ccee0f1..85226cb 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -380,10 +380,6 @@ static struct vm_operations_struct privcmd_vm_ops = {
 
 static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
 {
-	/* Unsupported for auto-translate guests. */
-	if (xen_feature(XENFEAT_auto_translated_physmap))
-		return -ENOSYS;
-
 	/* DONTCOPY is essential for Xen because copy_page_range doesn't know
 	 * how to recreate these mappings */
 	vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY | VM_PFNMAP;
-- 
1.7.2.5

Re: [PATCH 0/6] Xen patches for Linux 3.7

[Konrad Rzeszutek Wilk]

On Wed, Aug 22, 2012 at 05:19:18PM +0100, Stefano Stabellini wrote:
> Hi Konrad,
> the followings are the patches that I am proposing for Linux 3.7.
> I am leaving out the bulk of the ARM patches for the moment.

applied. going to test it overnight.
> 
> 
> Stefano Stabellini (6):
>       xen/events: fix unmask_evtchn for PV on HVM guests
>       xen: missing includes
>       xen: update xen_add_to_physmap interface
>       xen: Introduce xen_pfn_t for pfn and mfn types
>       xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
>       xen: allow privcmd for HVM guests
> 
>  arch/ia64/include/asm/xen/interface.h      |    7 ++++++-
>  arch/x86/include/asm/xen/interface.h       |    7 +++++++
>  arch/x86/xen/mmu.c                         |    3 +++
>  drivers/tty/hvc/hvc_xen.c                  |    2 ++
>  drivers/xen/events.c                       |   18 +++++++++++++++---
>  drivers/xen/grant-table.c                  |    1 +
>  drivers/xen/privcmd.c                      |    4 ----
>  drivers/xen/xenbus/xenbus_probe_frontend.c |    1 +
>  include/xen/interface/grant_table.h        |    4 ++--
>  include/xen/interface/memory.h             |    9 ++++++---
>  include/xen/interface/platform.h           |    4 ++--
>  include/xen/interface/xen.h                |    7 +++----
>  include/xen/privcmd.h                      |    3 +--
>  13 files changed, 49 insertions(+), 21 deletions(-)
> 
> 
> A git branch based on v3.6-rc2 is available here:
> 
> git://xenbits.xen.org/people/sstabellini/linux-pvhvm.git for_upstream_3.7
> 
> Cheers,
> 
> Stefano