Commit abb95b75 authored by Niklas Schnelle's avatar Niklas Schnelle Committed by Vasily Gorbik
Browse files

s390/pci: consolidate SR-IOV specific code 



currently we have multiple #ifdef CONFIG_PCI_IOV blocks spread over
different compliation units and headers, all dealing with SR-IOV
specific behavior.
This violates the style guide which discourages conditionally compiled
code blocks and hinders maintainability by speading SR-IOV functionality
over many files.

Let's move all of this into a conditionally compiled pci_iov.c file and
local header and prefix SR-IOV specific functions with zpci_iov_*.

Reviewed-by: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent da1694ad

arch/s390/pci/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -6,3 +6,4 @@ 
obj-$(CONFIG_PCI)	+= pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \

			   pci_event.o pci_debug.o pci_insn.o pci_mmio.o \

			   pci_bus.o

obj-$(CONFIG_PCI_IOV)	+= pci_iov.o

arch/s390/pci/pci.c

+3 −20
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ 
#include <asm/pci_dma.h>



#include "pci_bus.h"

#include "pci_iov.h"



/* list of all detected zpci devices */

static LIST_HEAD(zpci_list);
@@ -413,15 +414,6 @@ static struct pci_ops pci_root_ops = { 
	.write = pci_write,

};



#ifdef CONFIG_PCI_IOV

static struct resource iov_res = {

	.name	= "PCI IOV res",

	.start	= 0,

	.end	= -1,

	.flags	= IORESOURCE_MEM,

};

#endif



static void zpci_map_resources(struct pci_dev *pdev)

{

	struct zpci_dev *zdev = to_zpci(pdev);
@@ -442,16 +434,7 @@ static void zpci_map_resources(struct pci_dev *pdev) 
		pdev->resource[i].end = pdev->resource[i].start + len - 1;

	}



#ifdef CONFIG_PCI_IOV

	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {

		int bar = i + PCI_IOV_RESOURCES;



		len = pci_resource_len(pdev, bar);

		if (!len)

			continue;

		pdev->resource[bar].parent = &iov_res;

	}

#endif

	zpci_iov_map_resources(pdev);

}



static void zpci_unmap_resources(struct pci_dev *pdev)
@@ -703,7 +686,7 @@ void zpci_remove_device(struct zpci_dev *zdev) 
	pdev = pci_get_slot(zbus->bus, zdev->devfn);

	if (pdev) {

		if (pdev->is_virtfn)

			return zpci_remove_virtfn(pdev, zdev->vfn);

			return zpci_iov_remove_virtfn(pdev, zdev->vfn);

		pci_stop_and_remove_bus_device_locked(pdev);

	}

}

arch/s390/pci/pci_bus.c

+2 −64
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
#include <asm/pci_dma.h>



#include "pci_bus.h"

#include "pci_iov.h"



static LIST_HEAD(zbus_list);

static DEFINE_SPINLOCK(zbus_list_lock);
@@ -126,69 +127,6 @@ static struct zpci_bus *zpci_bus_alloc(int pchid) 
	return zbus;

}



#ifdef CONFIG_PCI_IOV

static int zpci_bus_link_virtfn(struct pci_dev *pdev,

		struct pci_dev *virtfn, int vfid)

{

	int rc;



	rc = pci_iov_sysfs_link(pdev, virtfn, vfid);

	if (rc)

		return rc;



	virtfn->is_virtfn = 1;

	virtfn->multifunction = 0;

	virtfn->physfn = pci_dev_get(pdev);



	return 0;

}



static int zpci_bus_setup_virtfn(struct zpci_bus *zbus,

		struct pci_dev *virtfn, int vfn)

{

	int i, cand_devfn;

	struct zpci_dev *zdev;

	struct pci_dev *pdev;

	int vfid = vfn - 1; /* Linux' vfid's start at 0 vfn at 1*/

	int rc = 0;



	if (!zbus->multifunction)

		return 0;



	/* If the parent PF for the given VF is also configured in the

	 * instance, it must be on the same zbus.

	 * We can then identify the parent PF by checking what

	 * devfn the VF would have if it belonged to that PF using the PF's

	 * stride and offset. Only if this candidate devfn matches the

	 * actual devfn will we link both functions.

	 */

	for (i = 0; i < ZPCI_FUNCTIONS_PER_BUS; i++) {

		zdev = zbus->function[i];

		if (zdev && zdev->is_physfn) {

			pdev = pci_get_slot(zbus->bus, zdev->devfn);

			if (!pdev)

				continue;

			cand_devfn = pci_iov_virtfn_devfn(pdev, vfid);

			if (cand_devfn == virtfn->devfn) {

				rc = zpci_bus_link_virtfn(pdev, virtfn, vfid);

				/* balance pci_get_slot() */

				pci_dev_put(pdev);

				break;

			}

			/* balance pci_get_slot() */

			pci_dev_put(pdev);

		}

	}

	return rc;

}

#else

static inline int zpci_bus_setup_virtfn(struct zpci_bus *zbus,

		struct pci_dev *virtfn, int vfn)

{

	return 0;

}

#endif



void pcibios_bus_add_device(struct pci_dev *pdev)

{

	struct zpci_dev *zdev = to_zpci(pdev);
@@ -198,7 +136,7 @@ void pcibios_bus_add_device(struct pci_dev *pdev) 
	 * perform PF/VF linking.

	 */

	if (zdev->vfn)

		zpci_bus_setup_virtfn(zdev->zbus, pdev, zdev->vfn);

		zpci_iov_setup_virtfn(zdev->zbus, pdev, zdev->vfn);



}

arch/s390/pci/pci_bus.h

+0 −12
Original line number Diff line number Diff line
@@ -30,15 +30,3 @@ static inline struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus, 
	return (devfn >= ZPCI_FUNCTIONS_PER_BUS) ? NULL : zbus->function[devfn];

}

#ifdef CONFIG_PCI_IOV

static inline void zpci_remove_virtfn(struct pci_dev *pdev, int vfn)

{



	pci_lock_rescan_remove();

	/* Linux' vfid's start at 0 vfn at 1 */

	pci_iov_remove_virtfn(pdev->physfn, vfn - 1);

	pci_unlock_rescan_remove();

}

#else /* CONFIG_PCI_IOV */

static inline void zpci_remove_virtfn(struct pci_dev *pdev, int vfn) {}

#endif /* CONFIG_PCI_IOV */

arch/s390/pci/pci_iov.c

0 → 100644
+97 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright IBM Corp. 2020

 *

 * Author(s):

 *   Niklas Schnelle <schnelle@linux.ibm.com>

 *

 */



#define KMSG_COMPONENT "zpci"

#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt



#include <linux/kernel.h>

#include <linux/pci.h>



static struct resource iov_res = {

	.name	= "PCI IOV res",

	.start	= 0,

	.end	= -1,

	.flags	= IORESOURCE_MEM,

};



void zpci_iov_map_resources(struct pci_dev *pdev)

{

	resource_size_t len;

	int i;



	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {

		int bar = i + PCI_IOV_RESOURCES;



		len = pci_resource_len(pdev, bar);

		if (!len)

			continue;

		pdev->resource[bar].parent = &iov_res;

	}

}



void zpci_iov_remove_virtfn(struct pci_dev *pdev, int vfn)

{

	pci_lock_rescan_remove();

	/* Linux' vfid's start at 0 vfn at 1 */

	pci_iov_remove_virtfn(pdev->physfn, vfn - 1);

	pci_unlock_rescan_remove();

}



static int zpci_iov_link_virtfn(struct pci_dev *pdev, struct pci_dev *virtfn, int vfid)

{

	int rc;



	rc = pci_iov_sysfs_link(pdev, virtfn, vfid);

	if (rc)

		return rc;



	virtfn->is_virtfn = 1;

	virtfn->multifunction = 0;

	virtfn->physfn = pci_dev_get(pdev);



	return 0;

}



int zpci_iov_setup_virtfn(struct zpci_bus *zbus, struct pci_dev *virtfn, int vfn)

{

	int i, cand_devfn;

	struct zpci_dev *zdev;

	struct pci_dev *pdev;

	int vfid = vfn - 1; /* Linux' vfid's start at 0 vfn at 1*/

	int rc = 0;



	if (!zbus->multifunction)

		return 0;



	/* If the parent PF for the given VF is also configured in the

	 * instance, it must be on the same zbus.

	 * We can then identify the parent PF by checking what

	 * devfn the VF would have if it belonged to that PF using the PF's

	 * stride and offset. Only if this candidate devfn matches the

	 * actual devfn will we link both functions.

	 */

	for (i = 0; i < ZPCI_FUNCTIONS_PER_BUS; i++) {

		zdev = zbus->function[i];

		if (zdev && zdev->is_physfn) {

			pdev = pci_get_slot(zbus->bus, zdev->devfn);

			if (!pdev)

				continue;

			cand_devfn = pci_iov_virtfn_devfn(pdev, vfid);

			if (cand_devfn == virtfn->devfn) {

				rc = zpci_iov_link_virtfn(pdev, virtfn, vfid);

				/* balance pci_get_slot() */

				pci_dev_put(pdev);

				break;

			}

			/* balance pci_get_slot() */

			pci_dev_put(pdev);

		}

	}

	return rc;

}

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