1 files changed, 681 insertions, 0 deletions

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
new file mode 100644
index 000000000000..b497daab3d4a
--- /dev/null
+++ b/drivers/pci/iov.c
@@ -0,0 +1,681 @@
+/*
+ * drivers/pci/iov.c
+ *
+ * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
+ *
+ * PCI Express I/O Virtualization (IOV) support.
+ *   Single Root IOV 1.0
+ */
+
+#include <linux/pci.h>
+#include <linux/mutex.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include "pci.h"
+
+#define VIRTFN_ID_LEN	16
+
+static inline u8 virtfn_bus(struct pci_dev *dev, int id)
+{
+	return dev->bus->number + ((dev->devfn + dev->sriov->offset +
+				    dev->sriov->stride * id) >> 8);
+}
+
+static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
+{
+	return (dev->devfn + dev->sriov->offset +
+		dev->sriov->stride * id) & 0xff;
+}
+
+static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
+{
+	int rc;
+	struct pci_bus *child;
+
+	if (bus->number == busnr)
+		return bus;
+
+	child = pci_find_bus(pci_domain_nr(bus), busnr);
+	if (child)
+		return child;
+
+	child = pci_add_new_bus(bus, NULL, busnr);
+	if (!child)
+		return NULL;
+
+	child->subordinate = busnr;
+	child->dev.parent = bus->bridge;
+	rc = pci_bus_add_child(child);
+	if (rc) {
+		pci_remove_bus(child);
+		return NULL;
+	}
+
+	return child;
+}
+
+static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
+{
+	struct pci_bus *child;
+
+	if (bus->number == busnr)
+		return;
+
+	child = pci_find_bus(pci_domain_nr(bus), busnr);
+	BUG_ON(!child);
+
+	if (list_empty(&child->devices))
+		pci_remove_bus(child);
+}
+
+static int virtfn_add(struct pci_dev *dev, int id, int reset)
+{
+	int i;
+	int rc;
+	u64 size;
+	char buf[VIRTFN_ID_LEN];
+	struct pci_dev *virtfn;
+	struct resource *res;
+	struct pci_sriov *iov = dev->sriov;
+
+	virtfn = alloc_pci_dev();
+	if (!virtfn)
+		return -ENOMEM;
+
+	mutex_lock(&iov->dev->sriov->lock);
+	virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
+	if (!virtfn->bus) {
+		kfree(virtfn);
+		mutex_unlock(&iov->dev->sriov->lock);
+		return -ENOMEM;
+	}
+	virtfn->devfn = virtfn_devfn(dev, id);
+	virtfn->vendor = dev->vendor;
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
+	pci_setup_device(virtfn);
+	virtfn->dev.parent = dev->dev.parent;
+
+	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
+		res = dev->resource + PCI_IOV_RESOURCES + i;
+		if (!res->parent)
+			continue;
+		virtfn->resource[i].name = pci_name(virtfn);
+		virtfn->resource[i].flags = res->flags;
+		size = resource_size(res);
+		do_div(size, iov->total);
+		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]);
+		BUG_ON(rc);
+	}
+
+	if (reset)
+		pci_execute_reset_function(virtfn);
+
+	pci_device_add(virtfn, virtfn->bus);
+	mutex_unlock(&iov->dev->sriov->lock);
+
+	virtfn->physfn = pci_dev_get(dev);
+	virtfn->is_virtfn = 1;
+
+	rc = pci_bus_add_device(virtfn);
+	if (rc)
+		goto failed1;
+	sprintf(buf, "virtfn%u", id);
+	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
+	if (rc)
+		goto failed1;
+	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
+	if (rc)
+		goto failed2;
+
+	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
+
+	return 0;
+
+failed2:
+	sysfs_remove_link(&dev->dev.kobj, buf);
+failed1:
+	pci_dev_put(dev);
+	mutex_lock(&iov->dev->sriov->lock);
+	pci_remove_bus_device(virtfn);
+	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
+	mutex_unlock(&iov->dev->sriov->lock);
+
+	return rc;
+}
+
+static void virtfn_remove(struct pci_dev *dev, int id, int reset)
+{
+	char buf[VIRTFN_ID_LEN];
+	struct pci_bus *bus;
+	struct pci_dev *virtfn;
+	struct pci_sriov *iov = dev->sriov;
+
+	bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
+	if (!bus)
+		return;
+
+	virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
+	if (!virtfn)
+		return;
+
+	pci_dev_put(virtfn);
+
+	if (reset) {
+		device_release_driver(&virtfn->dev);
+		pci_execute_reset_function(virtfn);
+	}
+
+	sprintf(buf, "virtfn%u", id);
+	sysfs_remove_link(&dev->dev.kobj, buf);
+	sysfs_remove_link(&virtfn->dev.kobj, "physfn");
+
+	mutex_lock(&iov->dev->sriov->lock);
+	pci_remove_bus_device(virtfn);
+	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
+	mutex_unlock(&iov->dev->sriov->lock);
+
+	pci_dev_put(dev);
+}
+
+static int sriov_migration(struct pci_dev *dev)
+{
+	u16 status;
+	struct pci_sriov *iov = dev->sriov;
+
+	if (!iov->nr_virtfn)
+		return 0;
+
+	if (!(iov->cap & PCI_SRIOV_CAP_VFM))
+		return 0;
+
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status);
+	if (!(status & PCI_SRIOV_STATUS_VFM))
+		return 0;
+
+	schedule_work(&iov->mtask);
+
+	return 1;
+}
+
+static void sriov_migration_task(struct work_struct *work)
+{
+	int i;
+	u8 state;
+	u16 status;
+	struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask);
+
+	for (i = iov->initial; i < iov->nr_virtfn; i++) {
+		state = readb(iov->mstate + i);
+		if (state == PCI_SRIOV_VFM_MI) {
+			writeb(PCI_SRIOV_VFM_AV, iov->mstate + i);
+			state = readb(iov->mstate + i);
+			if (state == PCI_SRIOV_VFM_AV)
+				virtfn_add(iov->self, i, 1);
+		} else if (state == PCI_SRIOV_VFM_MO) {
+			virtfn_remove(iov->self, i, 1);
+			writeb(PCI_SRIOV_VFM_UA, iov->mstate + i);
+			state = readb(iov->mstate + i);
+			if (state == PCI_SRIOV_VFM_AV)
+				virtfn_add(iov->self, i, 0);
+		}
+	}
+
+	pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status);
+	status &= ~PCI_SRIOV_STATUS_VFM;
+	pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status);
+}
+
+static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn)
+{
+	int bir;
+	u32 table;
+	resource_size_t pa;
+	struct pci_sriov *iov = dev->sriov;
+
+	if (nr_virtfn <= iov->initial)
+		return 0;
+
+	pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table);
+	bir = PCI_SRIOV_VFM_BIR(table);
+	if (bir > PCI_STD_RESOURCE_END)
+		return -EIO;
+
+	table = PCI_SRIOV_VFM_OFFSET(table);
+	if (table + nr_virtfn > pci_resource_len(dev, bir))
+		return -EIO;
+
+	pa = pci_resource_start(dev, bir) + table;
+	iov->mstate = ioremap(pa, nr_virtfn);
+	if (!iov->mstate)
+		return -ENOMEM;
+
+	INIT_WORK(&iov->mtask, sriov_migration_task);
+
+	iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR;
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+
+	return 0;
+}
+
+static void sriov_disable_migration(struct pci_dev *dev)
+{
+	struct pci_sriov *iov = dev->sriov;
+
+	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+
+	cancel_work_sync(&iov->mtask);
+	iounmap(iov->mstate);
+}
+
+static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
+{
+	int rc;
+	int i, j;
+	int nres;
+	u16 offset, stride, initial;
+	struct resource *res;
+	struct pci_dev *pdev;
+	struct pci_sriov *iov = dev->sriov;
+
+	if (!nr_virtfn)
+		return 0;
+
+	if (iov->nr_virtfn)
+		return -EINVAL;
+
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
+	if (initial > iov->total ||
+	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total)))
+		return -EIO;
+
+	if (nr_virtfn < 0 || nr_virtfn > iov->total ||
+	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
+		return -EINVAL;
+
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
+	if (!offset || (nr_virtfn > 1 && !stride))
+		return -EIO;
+
+	nres = 0;
+	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
+		res = dev->resource + PCI_IOV_RESOURCES + i;
+		if (res->parent)
+			nres++;
+	}
+	if (nres != iov->nres) {
+		dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
+		return -ENOMEM;
+	}
+
+	iov->offset = offset;
+	iov->stride = stride;
+
+	if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) {
+		dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
+		return -ENOMEM;
+	}
+
+	if (iov->link != dev->devfn) {
+		pdev = pci_get_slot(dev->bus, iov->link);
+		if (!pdev)
+			return -ENODEV;
+
+		pci_dev_put(pdev);
+
+		if (!pdev->is_physfn)
+			return -ENODEV;
+
+		rc = sysfs_create_link(&dev->dev.kobj,
+					&pdev->dev.kobj, "dep_link");
+		if (rc)
+			return rc;
+	}
+
+	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
+	pci_block_user_cfg_access(dev);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+	msleep(100);
+	pci_unblock_user_cfg_access(dev);
+
+	iov->initial = initial;
+	if (nr_virtfn < initial)
+		initial = nr_virtfn;
+
+	for (i = 0; i < initial; i++) {
+		rc = virtfn_add(dev, i, 0);
+		if (rc)
+			goto failed;
+	}
+
+	if (iov->cap & PCI_SRIOV_CAP_VFM) {
+		rc = sriov_enable_migration(dev, nr_virtfn);
+		if (rc)
+			goto failed;
+	}
+
+	kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
+	iov->nr_virtfn = nr_virtfn;
+
+	return 0;
+
+failed:
+	for (j = 0; j < i; j++)
+		virtfn_remove(dev, j, 0);
+
+	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
+	pci_block_user_cfg_access(dev);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+	ssleep(1);
+	pci_unblock_user_cfg_access(dev);
+
+	if (iov->link != dev->devfn)
+		sysfs_remove_link(&dev->dev.kobj, "dep_link");
+
+	return rc;
+}
+
+static void sriov_disable(struct pci_dev *dev)
+{
+	int i;
+	struct pci_sriov *iov = dev->sriov;
+
+	if (!iov->nr_virtfn)
+		return;
+
+	if (iov->cap & PCI_SRIOV_CAP_VFM)
+		sriov_disable_migration(dev);
+
+	for (i = 0; i < iov->nr_virtfn; i++)
+		virtfn_remove(dev, i, 0);
+
+	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
+	pci_block_user_cfg_access(dev);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+	ssleep(1);
+	pci_unblock_user_cfg_access(dev);
+
+	if (iov->link != dev->devfn)
+		sysfs_remove_link(&dev->dev.kobj, "dep_link");
+
+	iov->nr_virtfn = 0;
+}
+
+static int sriov_init(struct pci_dev *dev, int pos)
+{
+	int i;
+	int rc;
+	int nres;
+	u32 pgsz;
+	u16 ctrl, total, offset, stride;
+	struct pci_sriov *iov;
+	struct resource *res;
+	struct pci_dev *pdev;
+
+	if (dev->pcie_type != PCI_EXP_TYPE_RC_END &&
+	    dev->pcie_type != PCI_EXP_TYPE_ENDPOINT)
+		return -ENODEV;
+
+	pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
+	if (ctrl & PCI_SRIOV_CTRL_VFE) {
+		pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
+		ssleep(1);
+	}
+
+	pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
+	if (!total)
+		return 0;
+
+	ctrl = 0;
+	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
+		if (pdev->is_physfn)
+			goto found;
+
+	pdev = NULL;
+	if (pci_ari_enabled(dev->bus))
+		ctrl |= PCI_SRIOV_CTRL_ARI;
+
+found:
+	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
+	pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total);
+	pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);
+	pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);
+	if (!offset || (total > 1 && !stride))
+		return -EIO;
+
+	pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
+	i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
+	pgsz &= ~((1 << i) - 1);
+	if (!pgsz)
+		return -EIO;
+
+	pgsz &= ~(pgsz - 1);
+	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
+
+	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,
+				     pos + PCI_SRIOV_BAR + i * 4);
+		if (!res->flags)
+			continue;
+		if (resource_size(res) & (PAGE_SIZE - 1)) {
+			rc = -EIO;
+			goto failed;
+		}
+		res->end = res->start + resource_size(res) * total - 1;
+		nres++;
+	}
+
+	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
+	if (!iov) {
+		rc = -ENOMEM;
+		goto failed;
+	}
+
+	iov->pos = pos;
+	iov->nres = nres;
+	iov->ctrl = ctrl;
+	iov->total = total;
+	iov->offset = offset;
+	iov->stride = stride;
+	iov->pgsz = pgsz;
+	iov->self = dev;
+	pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
+	pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
+
+	if (pdev)
+		iov->dev = pci_dev_get(pdev);
+	else {
+		iov->dev = dev;
+		mutex_init(&iov->lock);
+	}
+
+	dev->sriov = iov;
+	dev->is_physfn = 1;
+
+	return 0;
+
+failed:
+	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
+		res = dev->resource + PCI_IOV_RESOURCES + i;
+		res->flags = 0;
+	}
+
+	return rc;
+}
+
+static void sriov_release(struct pci_dev *dev)
+{
+	BUG_ON(dev->sriov->nr_virtfn);
+
+	if (dev == dev->sriov->dev)
+		mutex_destroy(&dev->sriov->lock);
+	else
+		pci_dev_put(dev->sriov->dev);
+
+	kfree(dev->sriov);
+	dev->sriov = NULL;
+}
+
+static void sriov_restore_state(struct pci_dev *dev)
+{
+	int i;
+	u16 ctrl;
+	struct pci_sriov *iov = dev->sriov;
+
+	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
+	if (ctrl & PCI_SRIOV_CTRL_VFE)
+		return;
+
+	for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
+		pci_update_resource(dev, i);
+
+	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn);
+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
+	if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
+		msleep(100);
+}
+
+/**
+ * pci_iov_init - initialize the IOV capability
+ * @dev: the PCI device
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+int pci_iov_init(struct pci_dev *dev)
+{
+	int pos;
+
+	if (!dev->is_pcie)
+		return -ENODEV;
+
+	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
+	if (pos)
+		return sriov_init(dev, pos);
+
+	return -ENODEV;
+}
+
+/**
+ * pci_iov_release - release resources used by the IOV capability
+ * @dev: the PCI device
+ */
+void pci_iov_release(struct pci_dev *dev)
+{
+	if (dev->is_physfn)
+		sriov_release(dev);
+}
+
+/**
+ * pci_iov_resource_bar - get position of the SR-IOV BAR
+ * @dev: the PCI device
+ * @resno: the resource number
+ * @type: the BAR type to be filled in
+ *
+ * Returns position of the BAR encapsulated in the SR-IOV capability.
+ */
+int pci_iov_resource_bar(struct pci_dev *dev, int resno,
+			 enum pci_bar_type *type)
+{
+	if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END)
+		return 0;
+
+	BUG_ON(!dev->is_physfn);
+
+	*type = pci_bar_unknown;
+
+	return dev->sriov->pos + PCI_SRIOV_BAR +
+		4 * (resno - PCI_IOV_RESOURCES);
+}
+
+/**
+ * pci_restore_iov_state - restore the state of the IOV capability
+ * @dev: the PCI device
+ */
+void pci_restore_iov_state(struct pci_dev *dev)
+{
+	if (dev->is_physfn)
+		sriov_restore_state(dev);
+}
+
+/**
+ * pci_iov_bus_range - find bus range used by Virtual Function
+ * @bus: the PCI bus
+ *
+ * Returns max number of buses (exclude current one) used by Virtual
+ * Functions.
+ */
+int pci_iov_bus_range(struct pci_bus *bus)
+{
+	int max = 0;
+	u8 busnr;
+	struct pci_dev *dev;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		if (!dev->is_physfn)
+			continue;
+		busnr = virtfn_bus(dev, dev->sriov->total - 1);
+		if (busnr > max)
+			max = busnr;
+	}
+
+	return max ? max - bus->number : 0;
+}
+
+/**
+ * pci_enable_sriov - enable the SR-IOV capability
+ * @dev: the PCI device
+ * @nr_virtfn: number of virtual functions to enable
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
+{
+	might_sleep();
+
+	if (!dev->is_physfn)
+		return -ENODEV;
+
+	return sriov_enable(dev, nr_virtfn);
+}
+EXPORT_SYMBOL_GPL(pci_enable_sriov);
+
+/**
+ * pci_disable_sriov - disable the SR-IOV capability
+ * @dev: the PCI device
+ */
+void pci_disable_sriov(struct pci_dev *dev)
+{
+	might_sleep();
+
+	if (!dev->is_physfn)
+		return;
+
+	sriov_disable(dev);
+}
+EXPORT_SYMBOL_GPL(pci_disable_sriov);
+
+/**
+ * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration
+ * @dev: the PCI device
+ *
+ * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not.
+ *
+ * Physical Function driver is responsible to register IRQ handler using
+ * VF Migration Interrupt Message Number, and call this function when the
+ * interrupt is generated by the hardware.
+ */
+irqreturn_t pci_sriov_migration(struct pci_dev *dev)
+{
+	if (!dev->is_physfn)
+		return IRQ_NONE;
+
+	return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE;
+}
+EXPORT_SYMBOL_GPL(pci_sriov_migration);