Commit 0e6c9122 authored by Wei Yang's avatar Wei Yang Committed by Benjamin Herrenschmidt
Browse files

PCI: Keep individual VF BAR size in struct pci_sriov 



Currently we don't store the individual VF BAR size.  We calculate it when
needed by dividing the PF's IOV resource size (which contains space for
*all* the VFs) by total_VFs or by reading the BAR in the SR-IOV capability
again.

Keep the individual VF BAR size in struct pci_sriov.barsz[], add
pci_iov_resource_size() to retrieve it, and use that instead of doing the
division or reading the SR-IOV capability BAR.

[bhelgaas: rename to "barsz[]", simplify barsz[] index computation, remove
SR-IOV capability BAR sizing]
Signed-off-by: default avatarWei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent e88ae01d

drivers/pci/iov.c

+20 −19
Original line number Diff line number Diff line
@@ -57,6 +57,14 @@ static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) 
		pci_remove_bus(virtbus);

}



resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)

{

	if (!dev->is_physfn)

		return 0;



	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];

}



static int virtfn_add(struct pci_dev *dev, int id, int reset)

{

	int i;
@@ -92,8 +100,7 @@ static int virtfn_add(struct pci_dev *dev, int id, int reset) 
			continue;

		virtfn->resource[i].name = pci_name(virtfn);

		virtfn->resource[i].flags = res->flags;

		size = resource_size(res);

		do_div(size, iov->total_VFs);

		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);

		virtfn->resource[i].start = res->start + size * id;

		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;

		rc = request_resource(res, &virtfn->resource[i]);
@@ -311,7 +318,7 @@ static void sriov_disable(struct pci_dev *dev) 


static int sriov_init(struct pci_dev *dev, int pos)

{

	int i;

	int i, bar64;

	int rc;

	int nres;

	u32 pgsz;
@@ -360,10 +367,14 @@ found: 
	pgsz &= ~(pgsz - 1);

	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);



	iov = kzalloc(sizeof(*iov), GFP_KERNEL);

	if (!iov)

		return -ENOMEM;



	nres = 0;

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

		res = dev->resource + PCI_IOV_RESOURCES + i;

		i += __pci_read_base(dev, pci_bar_unknown, res,

		bar64 = __pci_read_base(dev, pci_bar_unknown, res,

					pos + PCI_SRIOV_BAR + i * 4);

		if (!res->flags)

			continue;
@@ -371,18 +382,14 @@ found: 
			rc = -EIO;

			goto failed;

		}

		iov->barsz[i] = resource_size(res);

		res->end = res->start + resource_size(res) * total - 1;

		dev_info(&dev->dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",

			 i, res, i, total);

		i += bar64;

		nres++;

	}



	iov = kzalloc(sizeof(*iov), GFP_KERNEL);

	if (!iov) {

		rc = -ENOMEM;

		goto failed;

	}



	iov->pos = pos;

	iov->nres = nres;

	iov->ctrl = ctrl;
@@ -414,6 +421,7 @@ failed: 
		res->flags = 0;

	}



	kfree(iov);

	return rc;

}
@@ -510,14 +518,7 @@ int pci_iov_resource_bar(struct pci_dev *dev, int resno) 
 */

resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)

{

	struct resource tmp;

	int reg = pci_iov_resource_bar(dev, resno);



	if (!reg)

		return 0;



	 __pci_read_base(dev, pci_bar_unknown, &tmp, reg);

	return resource_alignment(&tmp);

	return pci_iov_resource_size(dev, resno);

}



/**

drivers/pci/pci.h

+1 −0
Original line number Diff line number Diff line
@@ -247,6 +247,7 @@ struct pci_sriov { 
	struct pci_dev *dev;	/* lowest numbered PF */

	struct pci_dev *self;	/* this PF */

	struct mutex lock;	/* lock for VF bus */

	resource_size_t barsz[PCI_SRIOV_NUM_BARS];	/* VF BAR size */

};



#ifdef CONFIG_PCI_ATS

include/linux/pci.h

+3 −0
Original line number Diff line number Diff line
@@ -1675,6 +1675,7 @@ int pci_num_vf(struct pci_dev *dev); 
int pci_vfs_assigned(struct pci_dev *dev);

int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs);

int pci_sriov_get_totalvfs(struct pci_dev *dev);

resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno);

#else

static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)

{ return -ENODEV; }
@@ -1686,6 +1687,8 @@ static inline int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs) 
{ return 0; }

static inline int pci_sriov_get_totalvfs(struct pci_dev *dev)

{ return 0; }

static inline resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)

{ return 0; }

#endif



#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)

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