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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

[Xen-devel] [PATCH] cleanup patches for arch/x86/pci/xen.c (Xen PCI) for 3.1 (v1)

Proposing these ten patches for 3.1. The goal of these patches is to clean
up the Xen PCI glue code in xen.c and squash some common code together.

The patches are also available at:
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git 
stable/pci.cleanups.v1

I''ve tested them on PV, PV + PCI, PVonHVM, and PV initial domain
without
encountering any regressions.

 arch/x86/include/asm/xen/pci.h |    5 +-
 arch/x86/pci/xen.c             |  371 +++++++++++++++++-----------------------
 drivers/xen/events.c           |    7 +-
 include/xen/events.h           |    2 -
 4 files changed, 165 insertions(+), 220 deletions(-)

Konrad Rzeszutek Wilk (10):
      xen/pci: Shuffle code around.
      xen/pci: Update comments and fix empty spaces.
      xen/pci: Provide #ifdef CONFIG_ACPI to easy code squashing.
      xen/pci: In xen_register_pirq bind the GSI to the IRQ after the hypercall.
      xen/pci: Use the xen_register_pirq for HVM and initial domain users
      xen/pci: Squash pci_xen_initial_domain and xen_setup_pirqs together.
      xen/pci: Move the allocation of IRQs when there are no IOAPIC''s
to the end
      xen/pci: Retire unnecessary #ifdef CONFIG_ACPI
      xen/pci: Remove ''xen_allocate_pirq_gsi''.
      xen/pci: Use ''acpi_gsi_to_irq'' value unconditionally.


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http://lists.xensource.com/xen-devel

Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 01/10] xen/pci: Shuffle code around.

The file is hard to read. Move the code around so that
the contents of it follows a uniform format:
 - setup GSIs - PV, HVM, and initial domain case
 - then MSI/MSI-x setup - PV, HVM and then initial domain case.
 - then MSI/MSI-x teardown - same order.
 - lastly, the __init functions in PV, HVM, and initial domain order.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |  346 ++++++++++++++++++++++++++--------------------------
 1 files changed, 173 insertions(+), 173 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index f567965..ba4077b 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -19,6 +19,43 @@
 #include <xen/events.h>
 #include <asm/xen/pci.h>
 
+static int xen_pcifront_enable_irq(struct pci_dev *dev)
+{
+	int rc;
+	int share = 1;
+	int pirq;
+	u8 gsi;
+
+	rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
+	if (rc < 0) {
+		dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line:
%d\n",
+			 rc);
+		return rc;
+	}
+
+	rc = xen_allocate_pirq_gsi(gsi);
+	if (rc < 0) {
+		dev_warn(&dev->dev, "Xen PCI: failed to allocate a PIRQ for
GSI%d: %d\n",
+			 gsi, rc);
+		return rc;
+	}
+	pirq = rc;
+
+	if (gsi < NR_IRQS_LEGACY)
+		share = 0;
+
+	rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
+	if (rc < 0) {
+		dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to
IRQ: %d\n",
+			 gsi, pirq, rc);
+		return rc;
+	}
+
+	dev->irq = rc;
+	dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi,
dev->irq);
+	return 0;
+}
+
 #ifdef CONFIG_ACPI
 static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
 				 int trigger, int polarity)
@@ -58,6 +95,87 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32
gsi,
 }
 #endif
 
+#ifdef CONFIG_XEN_DOM0
+static int xen_register_pirq(u32 gsi, int gsi_override, int triggering)
+{
+	int rc, pirq, irq = -1;
+	struct physdev_map_pirq map_irq;
+	int shareable = 0;
+	char *name;
+
+	if (!xen_pv_domain())
+		return -1;
+
+	if (triggering == ACPI_EDGE_SENSITIVE) {
+		shareable = 0;
+		name = "ioapic-edge";
+	} else {
+		shareable = 1;
+		name = "ioapic-level";
+	}
+	pirq = xen_allocate_pirq_gsi(gsi);
+	if (pirq < 0)
+		goto out;
+
+	if (gsi_override >= 0)
+		irq = xen_bind_pirq_gsi_to_irq(gsi_override, pirq, shareable, name);
+	else
+		irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
+	if (irq < 0)
+		goto out;
+
+	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
pirq, irq, gsi);
+
+	map_irq.domid = DOMID_SELF;
+	map_irq.type = MAP_PIRQ_TYPE_GSI;
+	map_irq.index = gsi;
+	map_irq.pirq = pirq;
+
+	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+	if (rc) {
+		printk(KERN_WARNING "xen map irq failed %d\n", rc);
+		return -1;
+	}
+
+out:
+	return irq;
+}
+
+static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int
polarity)
+{
+	int rc, irq;
+	struct physdev_setup_gsi setup_gsi;
+
+	if (!xen_pv_domain())
+		return -1;
+
+	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity
%d\n",
+			gsi, triggering, polarity);
+
+	irq = xen_register_pirq(gsi, gsi_override, triggering);
+
+	setup_gsi.gsi = gsi;
+	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
+	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
+
+	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
+	if (rc == -EEXIST)
+		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
+	else if (rc) {
+		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
+				gsi, rc);
+	}
+
+	return irq;
+}
+
+static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
+				 int trigger, int polarity)
+{
+	return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity);
+}
+#endif
+
 #if defined(CONFIG_PCI_MSI)
 #include <linux/msi.h>
 #include <asm/msidef.h>
@@ -65,6 +183,46 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32
gsi,
 struct xen_pci_frontend_ops *xen_pci_frontend;
 EXPORT_SYMBOL_GPL(xen_pci_frontend);
 
+/*
+ * For MSI interrupts we have to use drivers/xen/event.s functions to
+ * allocate an irq_desc and setup the right */
+static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	int irq, ret, i;
+	struct msi_desc *msidesc;
+	int *v;
+
+	v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
+	if (!v)
+		return -ENOMEM;
+
+	if (type == PCI_CAP_ID_MSIX)
+		ret = xen_pci_frontend_enable_msix(dev, v, nvec);
+	else
+		ret = xen_pci_frontend_enable_msi(dev, v);
+	if (ret)
+		goto error;
+	i = 0;
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], 0,
+					       (type == PCI_CAP_ID_MSIX) ?
+					       "pcifront-msi-x" :
+					       "pcifront-msi",
+						DOMID_SELF);
+		if (irq < 0)
+			goto free;
+		i++;
+	}
+	kfree(v);
+	return 0;
+
+error:
+	dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X
support!\n");
+free:
+	kfree(v);
+	return ret;
+}
+
 #define XEN_PIRQ_MSI_DATA  (MSI_DATA_TRIGGER_EDGE | \
 		MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0))
 
@@ -123,67 +281,6 @@ error:
 	return -ENODEV;
 }
 
-/*
- * For MSI interrupts we have to use drivers/xen/event.s functions to
- * allocate an irq_desc and setup the right */
-
-
-static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
-{
-	int irq, ret, i;
-	struct msi_desc *msidesc;
-	int *v;
-
-	v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
-	if (!v)
-		return -ENOMEM;
-
-	if (type == PCI_CAP_ID_MSIX)
-		ret = xen_pci_frontend_enable_msix(dev, v, nvec);
-	else
-		ret = xen_pci_frontend_enable_msi(dev, v);
-	if (ret)
-		goto error;
-	i = 0;
-	list_for_each_entry(msidesc, &dev->msi_list, list) {
-		irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], 0,
-					       (type == PCI_CAP_ID_MSIX) ?
-					       "pcifront-msi-x" :
-					       "pcifront-msi",
-						DOMID_SELF);
-		if (irq < 0)
-			goto free;
-		i++;
-	}
-	kfree(v);
-	return 0;
-
-error:
-	dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X
support!\n");
-free:
-	kfree(v);
-	return ret;
-}
-
-static void xen_teardown_msi_irqs(struct pci_dev *dev)
-{
-	struct msi_desc *msidesc;
-
-	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
-	if (msidesc->msi_attrib.is_msix)
-		xen_pci_frontend_disable_msix(dev);
-	else
-		xen_pci_frontend_disable_msi(dev);
-
-	/* Free the IRQ''s and the msidesc using the generic code. */
-	default_teardown_msi_irqs(dev);
-}
-
-static void xen_teardown_msi_irq(unsigned int irq)
-{
-	xen_destroy_irq(irq);
-}
-
 #ifdef CONFIG_XEN_DOM0
 static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
@@ -242,44 +339,28 @@ out:
 	return ret;
 }
 #endif
-#endif
 
-static int xen_pcifront_enable_irq(struct pci_dev *dev)
+static void xen_teardown_msi_irqs(struct pci_dev *dev)
 {
-	int rc;
-	int share = 1;
-	int pirq;
-	u8 gsi;
+	struct msi_desc *msidesc;
 
-	rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
-	if (rc < 0) {
-		dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line:
%d\n",
-			 rc);
-		return rc;
-	}
+	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
+	if (msidesc->msi_attrib.is_msix)
+		xen_pci_frontend_disable_msix(dev);
+	else
+		xen_pci_frontend_disable_msi(dev);
 
-	rc = xen_allocate_pirq_gsi(gsi);
-	if (rc < 0) {
-		dev_warn(&dev->dev, "Xen PCI: failed to allocate a PIRQ for
GSI%d: %d\n",
-			 gsi, rc);
-		return rc;
-	}
-	pirq = rc;
+	/* Free the IRQ''s and the msidesc using the generic code. */
+	default_teardown_msi_irqs(dev);
+}
 
-	if (gsi < NR_IRQS_LEGACY)
-		share = 0;
+static void xen_teardown_msi_irq(unsigned int irq)
+{
+	xen_destroy_irq(irq);
+}
 
-	rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront");
-	if (rc < 0) {
-		dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to
IRQ: %d\n",
-			 gsi, pirq, rc);
-		return rc;
-	}
+#endif
 
-	dev->irq = rc;
-	dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi,
dev->irq);
-	return 0;
-}
 
 int __init pci_xen_init(void)
 {
@@ -327,79 +408,6 @@ int __init pci_xen_hvm_init(void)
 }
 
 #ifdef CONFIG_XEN_DOM0
-static int xen_register_pirq(u32 gsi, int gsi_override, int triggering)
-{
-	int rc, pirq, irq = -1;
-	struct physdev_map_pirq map_irq;
-	int shareable = 0;
-	char *name;
-
-	if (!xen_pv_domain())
-		return -1;
-
-	if (triggering == ACPI_EDGE_SENSITIVE) {
-		shareable = 0;
-		name = "ioapic-edge";
-	} else {
-		shareable = 1;
-		name = "ioapic-level";
-	}
-	pirq = xen_allocate_pirq_gsi(gsi);
-	if (pirq < 0)
-		goto out;
-
-	if (gsi_override >= 0)
-		irq = xen_bind_pirq_gsi_to_irq(gsi_override, pirq, shareable, name);
-	else
-		irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
-	if (irq < 0)
-		goto out;
-
-	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
pirq, irq, gsi);
-
-	map_irq.domid = DOMID_SELF;
-	map_irq.type = MAP_PIRQ_TYPE_GSI;
-	map_irq.index = gsi;
-	map_irq.pirq = pirq;
-
-	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
-	if (rc) {
-		printk(KERN_WARNING "xen map irq failed %d\n", rc);
-		return -1;
-	}
-
-out:
-	return irq;
-}
-
-static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int
polarity)
-{
-	int rc, irq;
-	struct physdev_setup_gsi setup_gsi;
-
-	if (!xen_pv_domain())
-		return -1;
-
-	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity
%d\n",
-			gsi, triggering, polarity);
-
-	irq = xen_register_pirq(gsi, gsi_override, triggering);
-
-	setup_gsi.gsi = gsi;
-	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
-	setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
-
-	rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi);
-	if (rc == -EEXIST)
-		printk(KERN_INFO "Already setup the GSI :%d\n", gsi);
-	else if (rc) {
-		printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n",
-				gsi, rc);
-	}
-
-	return irq;
-}
-
 static __init void xen_setup_acpi_sci(void)
 {
 	int rc;
@@ -447,12 +455,6 @@ static __init void xen_setup_acpi_sci(void)
 	return;
 }
 
-static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
-				 int trigger, int polarity)
-{
-	return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity);
-}
-
 static int __init pci_xen_initial_domain(void)
 {
 #ifdef CONFIG_PCI_MSI
@@ -493,9 +495,7 @@ void __init xen_setup_pirqs(void)
 			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
 	}
 }
-#endif
 
-#ifdef CONFIG_XEN_DOM0
 struct xen_device_domain_owner {
 	domid_t domain;
 	struct pci_dev *dev;
-- 
1.7.4.1


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Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 02/10] xen/pci: Update comments and fix empty spaces.

Update the out-dated comment at the beginning of the file.
Also provide the copyrights of folks who have been contributing
to this code lately.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |   15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index ba4077b..76b3980 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -1,8 +1,13 @@
 /*
- * Xen PCI Frontend Stub - puts some "dummy" functions in to the
Linux
- *			   x86 PCI core to support the Xen PCI Frontend
+ * Xen PCI - handle PCI (INTx) and MSI infrastructure calls for PV, HVM and
+ * initial domain support. We also handle the DSDT _PRT callbacks for
GSI''s
+ * used in HVM and initial domain mode (PV does not parse ACPI, so it has no
+ * concept of GSIs). Under PV we hook under the pnbbios API for IRQs and
+ * 0xcf8 PCI configuration read/write.
  *
  *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ *           Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+ *           Stefano Stabellini <stefano.stabellini@eu.citrix.com>
  */
 #include <linux/module.h>
 #include <linux/init.h>
@@ -183,9 +188,6 @@ static int acpi_register_gsi_xen(struct device *dev, u32
gsi,
 struct xen_pci_frontend_ops *xen_pci_frontend;
 EXPORT_SYMBOL_GPL(xen_pci_frontend);
 
-/*
- * For MSI interrupts we have to use drivers/xen/event.s functions to
- * allocate an irq_desc and setup the right */
 static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
 	int irq, ret, i;
@@ -361,7 +363,6 @@ static void xen_teardown_msi_irq(unsigned int irq)
 
 #endif
 
-
 int __init pci_xen_init(void)
 {
 	if (!xen_pv_domain() || xen_initial_domain())
@@ -427,7 +428,7 @@ static __init void xen_setup_acpi_sci(void)
 	}
 	trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
 	polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
-	
+
 	printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
 			"polarity=%d\n", gsi, trigger, polarity);
 
-- 
1.7.4.1


_______________________________________________
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Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 03/10] xen/pci: Provide #ifdef CONFIG_ACPI to easy code squashing.

In the past we would guard those code segments to be dependent
on CONFIG_XEN_DOM0 (which depends on CONFIG_ACPI) so this patch is
not stricly necessary. But the next patch will merge common
HVM and initial domain code and we want to make sure the CONFIG_ACPI
dependency is preserved - as HVM code does not depend on CONFIG_XEN_DOM0.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 76b3980..7ee39cc 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -101,6 +101,7 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32
gsi,
 #endif
 
 #ifdef CONFIG_XEN_DOM0
+#ifdef CONFIG_ACPI
 static int xen_register_pirq(u32 gsi, int gsi_override, int triggering)
 {
 	int rc, pirq, irq = -1;
@@ -180,6 +181,7 @@ static int acpi_register_gsi_xen(struct device *dev, u32
gsi,
 	return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity);
 }
 #endif
+#endif
 
 #if defined(CONFIG_PCI_MSI)
 #include <linux/msi.h>
@@ -409,6 +411,7 @@ int __init pci_xen_hvm_init(void)
 }
 
 #ifdef CONFIG_XEN_DOM0
+#ifdef CONFIG_ACPI
 static __init void xen_setup_acpi_sci(void)
 {
 	int rc;
@@ -455,16 +458,17 @@ static __init void xen_setup_acpi_sci(void)
 
 	return;
 }
-
+#endif
 static int __init pci_xen_initial_domain(void)
 {
 #ifdef CONFIG_PCI_MSI
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
 	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
 #endif
+#ifdef CONFIG_ACPI
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
-
+#endif
 	return 0;
 }
 
@@ -484,7 +488,7 @@ void __init xen_setup_pirqs(void)
 		}
 		return;
 	}
-
+#ifdef CONFIG_ACPI
 	/* Pre-allocate legacy irqs */
 	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 		int trigger, polarity;
@@ -495,6 +499,7 @@ void __init xen_setup_pirqs(void)
 		xen_register_pirq(irq, -1 /* no GSI override */,
 			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
 	}
+#endif
 }
 
 struct xen_device_domain_owner {
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 04/10] xen/pci: In xen_register_pirq bind the GSI to the IRQ after the hypercall.

Not before .. also that code segment starts looking like the HVM one.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |   32 ++++++++++++++++----------------
 1 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 7ee39cc..6b7d849 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -112,26 +112,10 @@ static int xen_register_pirq(u32 gsi, int gsi_override,
int triggering)
 	if (!xen_pv_domain())
 		return -1;
 
-	if (triggering == ACPI_EDGE_SENSITIVE) {
-		shareable = 0;
-		name = "ioapic-edge";
-	} else {
-		shareable = 1;
-		name = "ioapic-level";
-	}
 	pirq = xen_allocate_pirq_gsi(gsi);
 	if (pirq < 0)
 		goto out;
 
-	if (gsi_override >= 0)
-		irq = xen_bind_pirq_gsi_to_irq(gsi_override, pirq, shareable, name);
-	else
-		irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
-	if (irq < 0)
-		goto out;
-
-	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
pirq, irq, gsi);
-
 	map_irq.domid = DOMID_SELF;
 	map_irq.type = MAP_PIRQ_TYPE_GSI;
 	map_irq.index = gsi;
@@ -143,6 +127,22 @@ static int xen_register_pirq(u32 gsi, int gsi_override, int
triggering)
 		return -1;
 	}
 
+	if (triggering == ACPI_EDGE_SENSITIVE) {
+		shareable = 0;
+		name = "ioapic-edge";
+	} else {
+		shareable = 1;
+		name = "ioapic-level";
+	}
+
+	if (gsi_override >= 0)
+		gsi = gsi_override;
+
+	irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
+	if (irq < 0)
+		goto out;
+
+	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
pirq, irq, gsi);
 out:
 	return irq;
 }
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 05/10] xen/pci: Use the xen_register_pirq for HVM and initial domain users

. to cut down on the code duplicity.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |   75 ++++++++++++++++------------------------------------
 1 files changed, 23 insertions(+), 52 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 6b7d849..55c8cc3 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -62,60 +62,19 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev)
 }
 
 #ifdef CONFIG_ACPI
-static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
-				 int trigger, int polarity)
+static int xen_register_pirq(u32 gsi, int gsi_override, int triggering,
+			     bool alloc_pirq)
 {
-	int rc, irq;
+	int rc, pirq = -1, irq = -1;
 	struct physdev_map_pirq map_irq;
 	int shareable = 0;
 	char *name;
 
-	if (!xen_hvm_domain())
-		return -1;
-
-	map_irq.domid = DOMID_SELF;
-	map_irq.type = MAP_PIRQ_TYPE_GSI;
-	map_irq.index = gsi;
-	map_irq.pirq = -1;
-
-	rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
-	if (rc) {
-		printk(KERN_WARNING "xen map irq failed %d\n", rc);
-		return -1;
-	}
-
-	if (trigger == ACPI_EDGE_SENSITIVE) {
-		shareable = 0;
-		name = "ioapic-edge";
-	} else {
-		shareable = 1;
-		name = "ioapic-level";
+	if (alloc_pirq) {
+		pirq = xen_allocate_pirq_gsi(gsi);
+		if (pirq < 0)
+			goto out;
 	}
-
-	irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
-
-	printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq,
map_irq.pirq);
-
-	return irq;
-}
-#endif
-
-#ifdef CONFIG_XEN_DOM0
-#ifdef CONFIG_ACPI
-static int xen_register_pirq(u32 gsi, int gsi_override, int triggering)
-{
-	int rc, pirq, irq = -1;
-	struct physdev_map_pirq map_irq;
-	int shareable = 0;
-	char *name;
-
-	if (!xen_pv_domain())
-		return -1;
-
-	pirq = xen_allocate_pirq_gsi(gsi);
-	if (pirq < 0)
-		goto out;
-
 	map_irq.domid = DOMID_SELF;
 	map_irq.type = MAP_PIRQ_TYPE_GSI;
 	map_irq.index = gsi;
@@ -138,15 +97,26 @@ static int xen_register_pirq(u32 gsi, int gsi_override, int
triggering)
 	if (gsi_override >= 0)
 		gsi = gsi_override;
 
-	irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
+	irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name);
 	if (irq < 0)
 		goto out;
 
-	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
pirq, irq, gsi);
+	printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n",
map_irq.pirq, irq, gsi);
 out:
 	return irq;
 }
 
+static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
+				     int trigger, int polarity)
+{
+	if (!xen_hvm_domain())
+		return -1;
+
+	return xen_register_pirq(gsi, -1 /* no GSI override */,
+				 trigger, false /* no PIRQ allocation */);
+}
+
+#ifdef CONFIG_XEN_DOM0
 static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int
polarity)
 {
 	int rc, irq;
@@ -158,7 +128,7 @@ static int xen_register_gsi(u32 gsi, int gsi_override, int
triggering, int polar
 	printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity
%d\n",
 			gsi, triggering, polarity);
 
-	irq = xen_register_pirq(gsi, gsi_override, triggering);
+	irq = xen_register_pirq(gsi, gsi_override, triggering, true);
 
 	setup_gsi.gsi = gsi;
 	setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
@@ -497,7 +467,8 @@ void __init xen_setup_pirqs(void)
 			continue;
 
 		xen_register_pirq(irq, -1 /* no GSI override */,
-			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
+			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
+			true /* allocate IRQ */);
 	}
 #endif
 }
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 06/10] xen/pci: Squash pci_xen_initial_domain and xen_setup_pirqs together.

Since they are only called once and the rest of the pci_xen_*
functions follow the same pattern of setup.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/include/asm/xen/pci.h |    5 +++--
 arch/x86/pci/xen.c             |   17 ++++++-----------
 drivers/xen/events.c           |    2 +-
 3 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/arch/x86/include/asm/xen/pci.h b/arch/x86/include/asm/xen/pci.h
index 4fbda9a..968d57d 100644
--- a/arch/x86/include/asm/xen/pci.h
+++ b/arch/x86/include/asm/xen/pci.h
@@ -14,13 +14,14 @@ static inline int pci_xen_hvm_init(void)
 }
 #endif
 #if defined(CONFIG_XEN_DOM0)
-void __init xen_setup_pirqs(void);
+int __init pci_xen_initial_domain(void);
 int xen_find_device_domain_owner(struct pci_dev *dev);
 int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain);
 int xen_unregister_device_domain_owner(struct pci_dev *dev);
 #else
-static inline void __init xen_setup_pirqs(void)
+static inline int __init pci_xen_initial_domain(void)
 {
+	return -1;
 }
 static inline int xen_find_device_domain_owner(struct pci_dev *dev)
 {
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 55c8cc3..54d5f31 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -429,8 +429,11 @@ static __init void xen_setup_acpi_sci(void)
 	return;
 }
 #endif
-static int __init pci_xen_initial_domain(void)
+
+int __init pci_xen_initial_domain(void)
 {
+	int pirq, irq;
+
 #ifdef CONFIG_PCI_MSI
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
 	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
@@ -439,15 +442,6 @@ static int __init pci_xen_initial_domain(void)
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
 #endif
-	return 0;
-}
-
-void __init xen_setup_pirqs(void)
-{
-	int pirq, irq;
-
-	pci_xen_initial_domain();
-
 	if (0 == nr_ioapics) {
 		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 			pirq = xen_allocate_pirq_gsi(irq);
@@ -456,7 +450,7 @@ void __init xen_setup_pirqs(void)
 				break;
 			irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
 		}
-		return;
+		return 0;
 	}
 #ifdef CONFIG_ACPI
 	/* Pre-allocate legacy irqs */
@@ -471,6 +465,7 @@ void __init xen_setup_pirqs(void)
 			true /* allocate IRQ */);
 	}
 #endif
+	return 0;
 }
 
 struct xen_device_domain_owner {
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 30df85d..23f1b81 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -1693,6 +1693,6 @@ void __init xen_init_IRQ(void)
 	} else {
 		irq_ctx_init(smp_processor_id());
 		if (xen_initial_domain())
-			xen_setup_pirqs();
+			pci_xen_initial_domain();
 	}
 }
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 07/10] xen/pci: Move the allocation of IRQs when there are no IOAPIC''s to the end

. which means we can preset of NR_IRQS_LEGACY interrupts using
the ''acpi_get_override_irq'' API before this loop.
This means that we can get the IRQ''s polarity (and trigger) from either
the ACPI (or MP); or use the default values. This fixes a bug if we did
not have an IOAPIC we would not been able to preset the IRQ''s polarity
if the MP table existed.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |   21 +++++++++------------
 1 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 54d5f31..e585bf5 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -441,18 +441,6 @@ int __init pci_xen_initial_domain(void)
 #ifdef CONFIG_ACPI
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
-#endif
-	if (0 == nr_ioapics) {
-		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
-			pirq = xen_allocate_pirq_gsi(irq);
-			if (WARN(pirq < 0,
-				 "Could not allocate PIRQ for legacy interrupt\n"))
-				break;
-			irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
-		}
-		return 0;
-	}
-#ifdef CONFIG_ACPI
 	/* Pre-allocate legacy irqs */
 	for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 		int trigger, polarity;
@@ -465,6 +453,15 @@ int __init pci_xen_initial_domain(void)
 			true /* allocate IRQ */);
 	}
 #endif
+	if (0 == nr_ioapics) {
+		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
+			pirq = xen_allocate_pirq_gsi(irq);
+			if (WARN(pirq < 0,
+				 "Could not allocate PIRQ for legacy interrupt\n"))
+				break;
+			irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
+		}
+	}
 	return 0;
 }
 
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 08/10] xen/pci: Retire unnecessary #ifdef CONFIG_ACPI

As the code paths that are guarded by CONFIG_XEN_DOM0 already depend
on CONFIG_ACPI so the extra #ifdef is not required. The earlier
patch that added them in had done its job.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index e585bf5..6eddc52 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -381,7 +381,6 @@ int __init pci_xen_hvm_init(void)
 }
 
 #ifdef CONFIG_XEN_DOM0
-#ifdef CONFIG_ACPI
 static __init void xen_setup_acpi_sci(void)
 {
 	int rc;
@@ -428,7 +427,6 @@ static __init void xen_setup_acpi_sci(void)
 
 	return;
 }
-#endif
 
 int __init pci_xen_initial_domain(void)
 {
@@ -438,7 +436,6 @@ int __init pci_xen_initial_domain(void)
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
 	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
 #endif
-#ifdef CONFIG_ACPI
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
 	/* Pre-allocate legacy irqs */
@@ -452,7 +449,6 @@ int __init pci_xen_initial_domain(void)
 			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
 			true /* allocate IRQ */);
 	}
-#endif
 	if (0 == nr_ioapics) {
 		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 			pirq = xen_allocate_pirq_gsi(irq);
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 09/10] xen/pci: Remove ''xen_allocate_pirq_gsi''.

In the past (2.6.38) the ''xen_allocate_pirq_gsi'' would
allocate
an entry in a Linux IRQ -> {XEN_IRQ, type, event, ..} array. All
of that has been removed in 2.6.39 and the Xen IRQ subsystem uses
an linked list that is populated when the call to
''xen_allocate_irq_gsi'' (universally done from any of the
xen_bind_*
calls) is done. The ''xen_allocate_pirq_gsi'' is a NOP and there
is
no need for it anymore so lets remove it.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c   |   37 ++++++++++++-------------------------
 drivers/xen/events.c |    5 -----
 include/xen/events.h |    2 --
 3 files changed, 12 insertions(+), 32 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 6eddc52..f07c419 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -37,14 +37,8 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev)
 			 rc);
 		return rc;
 	}
-
-	rc = xen_allocate_pirq_gsi(gsi);
-	if (rc < 0) {
-		dev_warn(&dev->dev, "Xen PCI: failed to allocate a PIRQ for
GSI%d: %d\n",
-			 gsi, rc);
-		return rc;
-	}
-	pirq = rc;
+	/* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/
+	pirq = gsi;
 
 	if (gsi < NR_IRQS_LEGACY)
 		share = 0;
@@ -63,18 +57,16 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev)
 
 #ifdef CONFIG_ACPI
 static int xen_register_pirq(u32 gsi, int gsi_override, int triggering,
-			     bool alloc_pirq)
+			     bool set_pirq)
 {
 	int rc, pirq = -1, irq = -1;
 	struct physdev_map_pirq map_irq;
 	int shareable = 0;
 	char *name;
 
-	if (alloc_pirq) {
-		pirq = xen_allocate_pirq_gsi(gsi);
-		if (pirq < 0)
-			goto out;
-	}
+	if (set_pirq)
+		pirq = gsi;
+
 	map_irq.domid = DOMID_SELF;
 	map_irq.type = MAP_PIRQ_TYPE_GSI;
 	map_irq.index = gsi;
@@ -112,8 +104,8 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32
gsi,
 	if (!xen_hvm_domain())
 		return -1;
 
-	return xen_register_pirq(gsi, -1 /* no GSI override */,
-				 trigger, false /* no PIRQ allocation */);
+	return xen_register_pirq(gsi, -1 /* no GSI override */, trigger,
+				 false /* no mapping of GSI to PIRQ */);
 }
 
 #ifdef CONFIG_XEN_DOM0
@@ -430,7 +422,7 @@ static __init void xen_setup_acpi_sci(void)
 
 int __init pci_xen_initial_domain(void)
 {
-	int pirq, irq;
+	int irq;
 
 #ifdef CONFIG_PCI_MSI
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
@@ -447,16 +439,11 @@ int __init pci_xen_initial_domain(void)
 
 		xen_register_pirq(irq, -1 /* no GSI override */,
 			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
-			true /* allocate IRQ */);
+			true /* Map GSI to PIRQ */);
 	}
 	if (0 == nr_ioapics) {
-		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
-			pirq = xen_allocate_pirq_gsi(irq);
-			if (WARN(pirq < 0,
-				 "Could not allocate PIRQ for legacy interrupt\n"))
-				break;
-			irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
-		}
+		for (irq = 0; irq < NR_IRQS_LEGACY; irq++)
+			xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic");
 	}
 	return 0;
 }
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 23f1b81..da70f5c 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -615,11 +615,6 @@ static int find_irq_by_gsi(unsigned gsi)
 	return -1;
 }
 
-int xen_allocate_pirq_gsi(unsigned gsi)
-{
-	return gsi;
-}
-
 /*
  * Do not make any assumptions regarding the relationship between the
  * IRQ number returned here and the Xen pirq argument.
diff --git a/include/xen/events.h b/include/xen/events.h
index 9af21e1..d287997 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -74,8 +74,6 @@ int xen_set_callback_via(uint64_t via);
 void xen_evtchn_do_upcall(struct pt_regs *regs);
 void xen_hvm_evtchn_do_upcall(void);
 
-/* Allocate a pirq for a physical interrupt, given a gsi. */
-int xen_allocate_pirq_gsi(unsigned gsi);
 /* Bind a pirq for a physical interrupt to an irq. */
 int xen_bind_pirq_gsi_to_irq(unsigned gsi,
 			     unsigned pirq, int shareable, char *name);
-- 
1.7.4.1


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Konrad Rzeszutek Wilk

2011-Jul-07 19:08 UTC

head link

[Xen-devel] [PATCH 10/10] xen/pci: Use ''acpi_gsi_to_irq'' value unconditionally.

In the past we would only use the function''s value if the
returned value was not equal to ''acpi_sci_override_gsi''.
Meaning
that the INT_SRV_OVR values for global and source irq were different.
But it is OK to use the function''s value even when the global
and source irq are the same.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/pci/xen.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index f07c419..1017c7b 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -407,10 +407,9 @@ static __init void xen_setup_acpi_sci(void)
 	 * the ACPI interpreter and keels over since IRQ 9 has not been
 	 * setup as we had setup IRQ 20 for it).
 	 */
-	/* Check whether the GSI != IRQ */
 	if (acpi_gsi_to_irq(gsi, &irq) == 0) {
-		if (irq >= 0 && irq != gsi)
-			/* Bugger, we MUST have that IRQ. */
+		/* Use the provided value if it''s valid. */
+		if (irq >= 0)
 			gsi_override = irq;
 	}
 
-- 
1.7.4.1


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Xen devel - Jul 2011 - [PATCH] cleanup patches for arch/x86/pci/xen.c (Xen PCI) for 3.1 (v1)

[Xen-devel] [PATCH] cleanup patches for arch/x86/pci/xen.c (Xen PCI) for 3.1 (v1)

[Xen-devel] [PATCH 01/10] xen/pci: Shuffle code around.

[Xen-devel] [PATCH 02/10] xen/pci: Update comments and fix empty spaces.

[Xen-devel] [PATCH 03/10] xen/pci: Provide #ifdef CONFIG_ACPI to easy code squashing.

[Xen-devel] [PATCH 04/10] xen/pci: In xen_register_pirq bind the GSI to the IRQ after the hypercall.

[Xen-devel] [PATCH 05/10] xen/pci: Use the xen_register_pirq for HVM and initial domain users

[Xen-devel] [PATCH 06/10] xen/pci: Squash pci_xen_initial_domain and xen_setup_pirqs together.

[Xen-devel] [PATCH 07/10] xen/pci: Move the allocation of IRQs when there are no IOAPIC''s to the end

[Xen-devel] [PATCH 08/10] xen/pci: Retire unnecessary #ifdef CONFIG_ACPI

[Xen-devel] [PATCH 09/10] xen/pci: Remove ''xen_allocate_pirq_gsi''.

[Xen-devel] [PATCH 10/10] xen/pci: Use ''acpi_gsi_to_irq'' value unconditionally.