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Diffstat (limited to 'kernel/linux/igb_uio/igb_uio.c')
-rw-r--r--kernel/linux/igb_uio/igb_uio.c643
1 files changed, 643 insertions, 0 deletions
diff --git a/kernel/linux/igb_uio/igb_uio.c b/kernel/linux/igb_uio/igb_uio.c
new file mode 100644
index 0000000..4cae4dd
--- /dev/null
+++ b/kernel/linux/igb_uio/igb_uio.c
@@ -0,0 +1,643 @@
+// SPDX-License-Identifier: GPL-2.0
+/*-
+ * Copyright(c) 2010-2017 Intel Corporation. All rights reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/uio_driver.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/msi.h>
+#include <linux/version.h>
+#include <linux/slab.h>
+
+#include <rte_pci_dev_features.h>
+
+#include "compat.h"
+
+/**
+ * A structure describing the private information for a uio device.
+ */
+struct rte_uio_pci_dev {
+ struct uio_info info;
+ struct pci_dev *pdev;
+ enum rte_intr_mode mode;
+ struct mutex lock;
+ int refcnt;
+};
+
+static char *intr_mode;
+static enum rte_intr_mode igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX;
+/* sriov sysfs */
+static ssize_t
+show_max_vfs(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return snprintf(buf, 10, "%u\n", dev_num_vf(dev));
+}
+
+static ssize_t
+store_max_vfs(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int err = 0;
+ unsigned long max_vfs;
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ if (0 != kstrtoul(buf, 0, &max_vfs))
+ return -EINVAL;
+
+ if (0 == max_vfs)
+ pci_disable_sriov(pdev);
+ else if (0 == pci_num_vf(pdev))
+ err = pci_enable_sriov(pdev, max_vfs);
+ else /* do nothing if change max_vfs number */
+ err = -EINVAL;
+
+ return err ? err : count;
+}
+
+static DEVICE_ATTR(max_vfs, S_IRUGO | S_IWUSR, show_max_vfs, store_max_vfs);
+
+static struct attribute *dev_attrs[] = {
+ &dev_attr_max_vfs.attr,
+ NULL,
+};
+
+static const struct attribute_group dev_attr_grp = {
+ .attrs = dev_attrs,
+};
+
+#ifndef HAVE_PCI_MSI_MASK_IRQ
+/*
+ * It masks the msix on/off of generating MSI-X messages.
+ */
+static void
+igbuio_msix_mask_irq(struct msi_desc *desc, s32 state)
+{
+ u32 mask_bits = desc->masked;
+ unsigned int offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_VECTOR_CTRL;
+
+ if (state != 0)
+ mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
+ else
+ mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
+
+ if (mask_bits != desc->masked) {
+ writel(mask_bits, desc->mask_base + offset);
+ readl(desc->mask_base);
+ desc->masked = mask_bits;
+ }
+}
+
+/*
+ * It masks the msi on/off of generating MSI messages.
+ */
+static void
+igbuio_msi_mask_irq(struct pci_dev *pdev, struct msi_desc *desc, int32_t state)
+{
+ u32 mask_bits = desc->masked;
+ u32 offset = desc->irq - pdev->irq;
+ u32 mask = 1 << offset;
+
+ if (!desc->msi_attrib.maskbit)
+ return;
+
+ if (state != 0)
+ mask_bits &= ~mask;
+ else
+ mask_bits |= mask;
+
+ if (mask_bits != desc->masked) {
+ pci_write_config_dword(pdev, desc->mask_pos, mask_bits);
+ desc->masked = mask_bits;
+ }
+}
+
+static void
+igbuio_mask_irq(struct pci_dev *pdev, enum rte_intr_mode mode, s32 irq_state)
+{
+ struct msi_desc *desc;
+ struct list_head *msi_list;
+
+#ifdef HAVE_MSI_LIST_IN_GENERIC_DEVICE
+ msi_list = &pdev->dev.msi_list;
+#else
+ msi_list = &pdev->msi_list;
+#endif
+
+ if (mode == RTE_INTR_MODE_MSIX) {
+ list_for_each_entry(desc, msi_list, list)
+ igbuio_msix_mask_irq(desc, irq_state);
+ } else if (mode == RTE_INTR_MODE_MSI) {
+ list_for_each_entry(desc, msi_list, list)
+ igbuio_msi_mask_irq(pdev, desc, irq_state);
+ }
+}
+#endif
+
+/**
+ * This is the irqcontrol callback to be registered to uio_info.
+ * It can be used to disable/enable interrupt from user space processes.
+ *
+ * @param info
+ * pointer to uio_info.
+ * @param irq_state
+ * state value. 1 to enable interrupt, 0 to disable interrupt.
+ *
+ * @return
+ * - On success, 0.
+ * - On failure, a negative value.
+ */
+static int
+igbuio_pci_irqcontrol(struct uio_info *info, s32 irq_state)
+{
+ struct rte_uio_pci_dev *udev = info->priv;
+ struct pci_dev *pdev = udev->pdev;
+
+#ifdef HAVE_PCI_MSI_MASK_IRQ
+ struct irq_data *irq = irq_get_irq_data(udev->info.irq);
+#endif
+
+ pci_cfg_access_lock(pdev);
+
+ if (udev->mode == RTE_INTR_MODE_MSIX || udev->mode == RTE_INTR_MODE_MSI) {
+#ifdef HAVE_PCI_MSI_MASK_IRQ
+ if (irq_state == 1)
+ pci_msi_unmask_irq(irq);
+ else
+ pci_msi_mask_irq(irq);
+#else
+ igbuio_mask_irq(pdev, udev->mode, irq_state);
+#endif
+ }
+
+ if (udev->mode == RTE_INTR_MODE_LEGACY)
+ pci_intx(pdev, !!irq_state);
+
+ pci_cfg_access_unlock(pdev);
+
+ return 0;
+}
+
+/**
+ * This is interrupt handler which will check if the interrupt is for the right device.
+ * If yes, disable it here and will be enable later.
+ */
+static irqreturn_t
+igbuio_pci_irqhandler(int irq, void *dev_id)
+{
+ struct rte_uio_pci_dev *udev = (struct rte_uio_pci_dev *)dev_id;
+ struct uio_info *info = &udev->info;
+
+ /* Legacy mode need to mask in hardware */
+ if (udev->mode == RTE_INTR_MODE_LEGACY &&
+ !pci_check_and_mask_intx(udev->pdev))
+ return IRQ_NONE;
+
+ uio_event_notify(info);
+
+ /* Message signal mode, no share IRQ and automasked */
+ return IRQ_HANDLED;
+}
+
+static int
+igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
+{
+ int err = 0;
+#ifndef HAVE_ALLOC_IRQ_VECTORS
+ struct msix_entry msix_entry;
+#endif
+
+ switch (igbuio_intr_mode_preferred) {
+ case RTE_INTR_MODE_MSIX:
+ /* Only 1 msi-x vector needed */
+#ifndef HAVE_ALLOC_IRQ_VECTORS
+ msix_entry.entry = 0;
+ if (pci_enable_msix(udev->pdev, &msix_entry, 1) == 0) {
+ dev_dbg(&udev->pdev->dev, "using MSI-X");
+ udev->info.irq_flags = IRQF_NO_THREAD;
+ udev->info.irq = msix_entry.vector;
+ udev->mode = RTE_INTR_MODE_MSIX;
+ break;
+ }
+#else
+ if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) {
+ dev_dbg(&udev->pdev->dev, "using MSI-X");
+ udev->info.irq_flags = IRQF_NO_THREAD;
+ udev->info.irq = pci_irq_vector(udev->pdev, 0);
+ udev->mode = RTE_INTR_MODE_MSIX;
+ break;
+ }
+#endif
+
+ /* fall back to MSI */
+ case RTE_INTR_MODE_MSI:
+#ifndef HAVE_ALLOC_IRQ_VECTORS
+ if (pci_enable_msi(udev->pdev) == 0) {
+ dev_dbg(&udev->pdev->dev, "using MSI");
+ udev->info.irq_flags = IRQF_NO_THREAD;
+ udev->info.irq = udev->pdev->irq;
+ udev->mode = RTE_INTR_MODE_MSI;
+ break;
+ }
+#else
+ if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSI) == 1) {
+ dev_dbg(&udev->pdev->dev, "using MSI");
+ udev->info.irq_flags = IRQF_NO_THREAD;
+ udev->info.irq = pci_irq_vector(udev->pdev, 0);
+ udev->mode = RTE_INTR_MODE_MSI;
+ break;
+ }
+#endif
+ /* fall back to INTX */
+ case RTE_INTR_MODE_LEGACY:
+ if (pci_intx_mask_supported(udev->pdev)) {
+ dev_dbg(&udev->pdev->dev, "using INTX");
+ udev->info.irq_flags = IRQF_SHARED | IRQF_NO_THREAD;
+ udev->info.irq = udev->pdev->irq;
+ udev->mode = RTE_INTR_MODE_LEGACY;
+ break;
+ }
+ dev_notice(&udev->pdev->dev, "PCI INTX mask not supported\n");
+ /* fall back to no IRQ */
+ case RTE_INTR_MODE_NONE:
+ udev->mode = RTE_INTR_MODE_NONE;
+ udev->info.irq = UIO_IRQ_NONE;
+ break;
+
+ default:
+ dev_err(&udev->pdev->dev, "invalid IRQ mode %u",
+ igbuio_intr_mode_preferred);
+ udev->info.irq = UIO_IRQ_NONE;
+ err = -EINVAL;
+ }
+
+ if (udev->info.irq != UIO_IRQ_NONE)
+ err = request_irq(udev->info.irq, igbuio_pci_irqhandler,
+ udev->info.irq_flags, udev->info.name,
+ udev);
+ dev_info(&udev->pdev->dev, "uio device registered with irq %ld\n",
+ udev->info.irq);
+
+ return err;
+}
+
+static void
+igbuio_pci_disable_interrupts(struct rte_uio_pci_dev *udev)
+{
+ if (udev->info.irq) {
+ free_irq(udev->info.irq, udev);
+ udev->info.irq = 0;
+ }
+
+#ifndef HAVE_ALLOC_IRQ_VECTORS
+ if (udev->mode == RTE_INTR_MODE_MSIX)
+ pci_disable_msix(udev->pdev);
+ if (udev->mode == RTE_INTR_MODE_MSI)
+ pci_disable_msi(udev->pdev);
+#else
+ if (udev->mode == RTE_INTR_MODE_MSIX ||
+ udev->mode == RTE_INTR_MODE_MSI)
+ pci_free_irq_vectors(udev->pdev);
+#endif
+}
+
+
+/**
+ * This gets called while opening uio device file.
+ */
+static int
+igbuio_pci_open(struct uio_info *info, struct inode *inode)
+{
+ struct rte_uio_pci_dev *udev = info->priv;
+ struct pci_dev *dev = udev->pdev;
+ int err;
+
+ mutex_lock(&udev->lock);
+ if (++udev->refcnt > 1) {
+ mutex_unlock(&udev->lock);
+ return 0;
+ }
+
+ /* set bus master, which was cleared by the reset function */
+ pci_set_master(dev);
+
+ /* enable interrupts */
+ err = igbuio_pci_enable_interrupts(udev);
+ mutex_unlock(&udev->lock);
+ if (err) {
+ dev_err(&dev->dev, "Enable interrupt fails\n");
+ return err;
+ }
+ return 0;
+}
+
+static int
+igbuio_pci_release(struct uio_info *info, struct inode *inode)
+{
+ struct rte_uio_pci_dev *udev = info->priv;
+ struct pci_dev *dev = udev->pdev;
+
+ mutex_lock(&udev->lock);
+ if (--udev->refcnt > 0) {
+ mutex_unlock(&udev->lock);
+ return 0;
+ }
+
+ /* disable interrupts */
+ igbuio_pci_disable_interrupts(udev);
+
+ /* stop the device from further DMA */
+ pci_clear_master(dev);
+
+ mutex_unlock(&udev->lock);
+ return 0;
+}
+
+/* Remap pci resources described by bar #pci_bar in uio resource n. */
+static int
+igbuio_pci_setup_iomem(struct pci_dev *dev, struct uio_info *info,
+ int n, int pci_bar, const char *name)
+{
+ unsigned long addr, len;
+ void *internal_addr;
+
+ if (n >= ARRAY_SIZE(info->mem))
+ return -EINVAL;
+
+ addr = pci_resource_start(dev, pci_bar);
+ len = pci_resource_len(dev, pci_bar);
+ if (addr == 0 || len == 0)
+ return -1;
+ internal_addr = ioremap(addr, len);
+ if (internal_addr == NULL)
+ return -1;
+ info->mem[n].name = name;
+ info->mem[n].addr = addr;
+ info->mem[n].internal_addr = internal_addr;
+ info->mem[n].size = len;
+ info->mem[n].memtype = UIO_MEM_PHYS;
+ return 0;
+}
+
+/* Get pci port io resources described by bar #pci_bar in uio resource n. */
+static int
+igbuio_pci_setup_ioport(struct pci_dev *dev, struct uio_info *info,
+ int n, int pci_bar, const char *name)
+{
+ unsigned long addr, len;
+
+ if (n >= ARRAY_SIZE(info->port))
+ return -EINVAL;
+
+ addr = pci_resource_start(dev, pci_bar);
+ len = pci_resource_len(dev, pci_bar);
+ if (addr == 0 || len == 0)
+ return -EINVAL;
+
+ info->port[n].name = name;
+ info->port[n].start = addr;
+ info->port[n].size = len;
+ info->port[n].porttype = UIO_PORT_X86;
+
+ return 0;
+}
+
+/* Unmap previously ioremap'd resources */
+static void
+igbuio_pci_release_iomem(struct uio_info *info)
+{
+ int i;
+
+ for (i = 0; i < MAX_UIO_MAPS; i++) {
+ if (info->mem[i].internal_addr)
+ iounmap(info->mem[i].internal_addr);
+ }
+}
+
+static int
+igbuio_setup_bars(struct pci_dev *dev, struct uio_info *info)
+{
+ int i, iom, iop, ret;
+ unsigned long flags;
+ static const char *bar_names[PCI_STD_RESOURCE_END + 1] = {
+ "BAR0",
+ "BAR1",
+ "BAR2",
+ "BAR3",
+ "BAR4",
+ "BAR5",
+ };
+
+ iom = 0;
+ iop = 0;
+
+ for (i = 0; i < ARRAY_SIZE(bar_names); i++) {
+ if (pci_resource_len(dev, i) != 0 &&
+ pci_resource_start(dev, i) != 0) {
+ flags = pci_resource_flags(dev, i);
+ if (flags & IORESOURCE_MEM) {
+ ret = igbuio_pci_setup_iomem(dev, info, iom,
+ i, bar_names[i]);
+ if (ret != 0)
+ return ret;
+ iom++;
+ } else if (flags & IORESOURCE_IO) {
+ ret = igbuio_pci_setup_ioport(dev, info, iop,
+ i, bar_names[i]);
+ if (ret != 0)
+ return ret;
+ iop++;
+ }
+ }
+ }
+
+ return (iom != 0 || iop != 0) ? ret : -ENOENT;
+}
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0)
+static int __devinit
+#else
+static int
+#endif
+igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+ struct rte_uio_pci_dev *udev;
+ dma_addr_t map_dma_addr;
+ void *map_addr;
+ int err;
+
+ udev = kzalloc(sizeof(struct rte_uio_pci_dev), GFP_KERNEL);
+ if (!udev)
+ return -ENOMEM;
+
+ mutex_init(&udev->lock);
+ /*
+ * enable device: ask low-level code to enable I/O and
+ * memory
+ */
+ err = pci_enable_device(dev);
+ if (err != 0) {
+ dev_err(&dev->dev, "Cannot enable PCI device\n");
+ goto fail_free;
+ }
+
+ /* enable bus mastering on the device */
+ pci_set_master(dev);
+
+ /* remap IO memory */
+ err = igbuio_setup_bars(dev, &udev->info);
+ if (err != 0)
+ goto fail_release_iomem;
+
+ /* set 64-bit DMA mask */
+ err = pci_set_dma_mask(dev, DMA_BIT_MASK(64));
+ if (err != 0) {
+ dev_err(&dev->dev, "Cannot set DMA mask\n");
+ goto fail_release_iomem;
+ }
+
+ err = pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(64));
+ if (err != 0) {
+ dev_err(&dev->dev, "Cannot set consistent DMA mask\n");
+ goto fail_release_iomem;
+ }
+
+ /* fill uio infos */
+ udev->info.name = "igb_uio";
+ udev->info.version = "0.1";
+ udev->info.irqcontrol = igbuio_pci_irqcontrol;
+ udev->info.open = igbuio_pci_open;
+ udev->info.release = igbuio_pci_release;
+ udev->info.priv = udev;
+ udev->pdev = dev;
+
+ err = sysfs_create_group(&dev->dev.kobj, &dev_attr_grp);
+ if (err != 0)
+ goto fail_release_iomem;
+
+ /* register uio driver */
+ err = uio_register_device(&dev->dev, &udev->info);
+ if (err != 0)
+ goto fail_remove_group;
+
+ pci_set_drvdata(dev, udev);
+
+ /*
+ * Doing a harmless dma mapping for attaching the device to
+ * the iommu identity mapping if kernel boots with iommu=pt.
+ * Note this is not a problem if no IOMMU at all.
+ */
+ map_addr = dma_alloc_coherent(&dev->dev, 1024, &map_dma_addr,
+ GFP_KERNEL);
+ if (map_addr)
+ memset(map_addr, 0, 1024);
+
+ if (!map_addr)
+ dev_info(&dev->dev, "dma mapping failed\n");
+ else {
+ dev_info(&dev->dev, "mapping 1K dma=%#llx host=%p\n",
+ (unsigned long long)map_dma_addr, map_addr);
+
+ dma_free_coherent(&dev->dev, 1024, map_addr, map_dma_addr);
+ dev_info(&dev->dev, "unmapping 1K dma=%#llx host=%p\n",
+ (unsigned long long)map_dma_addr, map_addr);
+ }
+
+ return 0;
+
+fail_remove_group:
+ sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp);
+fail_release_iomem:
+ igbuio_pci_release_iomem(&udev->info);
+ pci_disable_device(dev);
+fail_free:
+ kfree(udev);
+
+ return err;
+}
+
+static void
+igbuio_pci_remove(struct pci_dev *dev)
+{
+ struct rte_uio_pci_dev *udev = pci_get_drvdata(dev);
+
+ mutex_destroy(&udev->lock);
+ sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp);
+ uio_unregister_device(&udev->info);
+ igbuio_pci_release_iomem(&udev->info);
+ pci_disable_device(dev);
+ pci_set_drvdata(dev, NULL);
+ kfree(udev);
+}
+
+static int
+igbuio_config_intr_mode(char *intr_str)
+{
+ if (!intr_str) {
+ pr_info("Use MSIX interrupt by default\n");
+ return 0;
+ }
+
+ if (!strcmp(intr_str, RTE_INTR_MODE_MSIX_NAME)) {
+ igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX;
+ pr_info("Use MSIX interrupt\n");
+ } else if (!strcmp(intr_str, RTE_INTR_MODE_MSI_NAME)) {
+ igbuio_intr_mode_preferred = RTE_INTR_MODE_MSI;
+ pr_info("Use MSI interrupt\n");
+ } else if (!strcmp(intr_str, RTE_INTR_MODE_LEGACY_NAME)) {
+ igbuio_intr_mode_preferred = RTE_INTR_MODE_LEGACY;
+ pr_info("Use legacy interrupt\n");
+ } else {
+ pr_info("Error: bad parameter - %s\n", intr_str);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static struct pci_driver igbuio_pci_driver = {
+ .name = "igb_uio",
+ .id_table = NULL,
+ .probe = igbuio_pci_probe,
+ .remove = igbuio_pci_remove,
+};
+
+static int __init
+igbuio_pci_init_module(void)
+{
+ int ret;
+
+ ret = igbuio_config_intr_mode(intr_mode);
+ if (ret < 0)
+ return ret;
+
+ return pci_register_driver(&igbuio_pci_driver);
+}
+
+static void __exit
+igbuio_pci_exit_module(void)
+{
+ pci_unregister_driver(&igbuio_pci_driver);
+}
+
+module_init(igbuio_pci_init_module);
+module_exit(igbuio_pci_exit_module);
+
+module_param(intr_mode, charp, S_IRUGO);
+MODULE_PARM_DESC(intr_mode,
+"igb_uio interrupt mode (default=msix):\n"
+" " RTE_INTR_MODE_MSIX_NAME " Use MSIX interrupt\n"
+" " RTE_INTR_MODE_MSI_NAME " Use MSI interrupt\n"
+" " RTE_INTR_MODE_LEGACY_NAME " Use Legacy interrupt\n"
+"\n");
+
+MODULE_DESCRIPTION("UIO driver for Intel IGB PCI cards");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");