@@ -0,0 +1,176 @@
+-------------------------------------------------------------------------------
+The VFIO "driver" is used to allow privileged AND non-privileged processes to
+implement user-level device drivers for any well-behaved PCI, PCI-X, and PCIe
+devices.
+
+Why is this interesting? Some applications, especially in the high performance
+computing field, need access to hardware functions with as little overhead as
+possible. Examples are in network adapters (typically non tcp/ip based) and
+in compute accelerators - i.e., array processors, FPGA processors, etc.
+Previous to the VFIO drivers these apps would need either a kernel-level
+driver (with corrsponding overheads), or else root permissions to directly
+access the hardware. The VFIO driver allows generic access to the hardware
+from non-privileged apps IF the hardware is "well-behaved" enough for this
+to be safe.
+
+While there have long been ways to implement user-level drivers using specific
+corresponding drivers in the kernel, it was not until the introduction of the
+UIO driver framework, and the uio_pci_generic driver that one could have a
+generic kernel component supporting many types of user level drivers. However,
+even with the uio_pci_generic driver, processes implementing the user level
+drivers had to be trusted - they could do dangerous manipulation of DMA
+addreses and were required to be root to write PCI configuration space
+registers.
+
+Recent hardware technologies - I/O MMUs and PCI I/O Virtualization - provide
+new hardware capabilities which the VFIO solution exploits to allow non-root
+user level drivers. The main role of the IOMMU is to ensure that DMA accesses
+from devices go only to the appropriate memory locations, this allows VFIO to
+ensure that user level drivers do not corrupt inappropriate memory. PCI I/O
+virtualization (SR-IOV) was defined to allow "pass-through" of virtual devices
+to guest virtual machines. VFIO in essence implements pass-through of devices
+to user processes, not virtual machines. SR-IOV devices implement a
+traditional PCI device (the physical function) and a dynamic number of special
+PCI devices (virtual functions) whose feature set is somewhat restricted - in
+order to allow the operating system or virtual machine monitor to ensure the
+safe operation of the system.
+
+Any SR-IOV virtual function meets the VFIO definition of "well-behaved", but
+there are many other non-IOV PCI devices which also meet the defintion.
+Elements of this definition are:
+- The size of any memory BARs to be mmap'ed into the user process space must be
+ a multiple of the system page size.
+- If MSI-X interrupts are used, the device driver must not attempt to mmap or
+ write the MSI-X vector area.
+- If the device is a PCI device (not PCI-X or PCIe), it must conform to PCI
+ revision 2.3 to allow its interrupts to be masked in a generic way.
+- The device must not use the PCI configuration space in any non-standard way,
+ i.e., the user level driver will be permitted only to read and write standard
+ fields of the PCI config space, and only if those fields cannot cause harm to
+ the system. In addition, some fields are "virtualized", so that the user
+ driver can read/write them like a kernel driver, but they do not affect the
+ real device.
+- For now, there is no support for user access to the PCIe and PCI-X extended
+ capabilities configuration space.
+
+Even with these restrictions, there are bound to be devices which are unsafe
+for user level use - it is still up to the system admin to decide whether to
+grant access to the device. When the vfio module is loaded, it will have
+access to no devices until the desired PCI devices are "bound" to the driver.
+First, make sure the devices are not bound to another kernel driver. You can
+unload that driver if you wish to unbind all its devices, or else enter the
+driver's sysfs directory, and unbind a specific device:
+ cd /sys/bus/pci/drivers/<drivername>
+ echo 0000:06:02.00 > unbind
+(The 0000:06:02.00 is a fully qualified PCI device name - different for each
+device). Now, to bind to the vfio driver, go to /sys/bus/pci/drivers/vfio and
+write the PCI device type of the target device to the new_id file:
+ echo 8086 10ca > new_id
+(8086 10ca are the vendor and device type for the Intel 82576 virtual function
+devices). A /dev/vfio<N> entry will be created for each device bound. The final
+step is to grant users permission by changing the mode and/or owner of the /dev
+entry - "chmod 666 /dev/vfio0".
+
+Reads & Writes:
+
+The user driver will typically use mmap to access the memory BAR(s) of a
+device; the I/O BARs and the PCI config space may be accessed through normal
+read and write system calls. Only 1 file descriptor is needed for all driver
+functions -- the desired BAR for I/O, memory, or config space is indicated via
+high-order bits of the file offset. For instance, the following implements a
+write to the PCI config space:
+
+ #include <linux/vfio.h>
+ void pci_write_config_word(int pci_fd, u16 off, u16 wd)
+ {
+ off_t cfg_off = VFIO_PCI_CONFIG_OFF + off;
+
+ if (pwrite(pci_fd, &wd, 2, cfg_off) != 2)
+ perror("pwrite config_dword");
+ }
+
+The routines vfio_pci_space_to_offset and vfio_offset_to_pci_space are provided
+in vfio.h to convert bar numbers to file offsets and vice-versa.
+
+Interrupts:
+
+Device interrupts are translated by the vfio driver into input events on event
+notification file descriptors created by the eventfd system call. The user
+program must one or more event descriptors and pass them to the vfio driver
+via ioctls to arrange for the interrupt mapping:
+1.
+ efd = eventfd(0, 0);
+ ioctl(vfio_fd, VFIO_EVENTFD_IRQ, &efd);
+ This provides an eventfd for traditional IRQ interrupts.
+ IRQs will be disable after each interrupt until the driver
+ re-enables them via the PCI COMMAND register.
+2.
+ efd = eventfd(0, 0);
+ ioctl(vfio_fd, VFIO_EVENTFD_MSI, &efd);
+ This connects MSI interrupts to an eventfd.
+3.
+ int arg[N+1];
+ arg[0] = N;
+ arg[1..N] = eventfd(0, 0);
+ ioctl(vfio_fd, VFIO_EVENTFDS_MSIX, arg);
+ This connects N MSI-X interrupts with N eventfds.
+
+Waiting and checking for interrupts is done by the user program by reads,
+polls, or selects on the related event file descriptors.
+
+DMA:
+
+The VFIO driver uses ioctls to allow the user level driver to get DMA
+addresses which correspond to virtual addresses. In systems with IOMMUs,
+each PCI device will have its own address space for DMA operations, so when
+the user level driver programs the device registers, only addresses known to
+the IOMMU will be valid, any others will be rejected. The IOMMU creates the
+illusion (to the device) that multi-page buffers are physically contiguous,
+so a single DMA operation can safely span multiple user pages. Note that
+the VFIO driver is still useful in systems without IOMMUs, but only for
+trusted processes which can deal with DMAs which do not span pages (Huge
+pages count as a single page also).
+
+If the user process desires many DMA buffers, it may be wise to do a mapping
+of a single large buffer, and then allocate the smaller buffers from the
+large one.
+
+The DMA buffers are locked into physical memory for the duration of their
+existence - until VFIO_DMA_UNMAP is called, until the user pages are
+unmapped from the user process, or until the vfio file descriptor is closed.
+The user process must have permission to lock the pages given by the ulimit(-l)
+command, which in turn relies on settings in the /etc/security/limits.conf
+file.
+
+The vfio_dma_map structure is used as an argument to the ioctls which
+do the DMA mapping. Its vaddr, dmaaddr, and size fields must always be a
+multiple of a page. Its rdwr field is zero for read-only (outbound), and
+non-zero for read/write buffers.
+
+ struct vfio_dma_map {
+ __u64 vaddr; /* process virtual addr */
+ __u64 dmaaddr; /* desired and/or returned dma address */
+ __u64 size; /* size in bytes */
+ int rdwr; /* bool: 0 for r/o; 1 for r/w */
+ };
+
+The VFIO_DMA_MAP_ANYWHERE is called with a vfio_dma_map structure as its
+argument, and returns the structure with a valid dmaaddr field.
+
+The VFIO_DMA_MAP_IOVA is called with a vfio_dma_map structure with the
+dmaaddr field already assigned. The system will attempt to map the DMA
+buffer into the IO space at the givne dmaaddr. This is expected to be
+useful if KVM or other virtualization facilities use this driver.
+
+The VFIO_DMA_UNMAP takes a fully filled vfio_dma_map structure and unmaps
+the buffer and releases the corresponding system resources.
+
+The VFIO_DMA_MASK ioctl is used to set the maximum permissible DMA address
+(device dependent). It takes a single unsigned 64 bit integer as an argument.
+This call also has the side effect on enabled PCI bus mastership.
+
+Miscellaneous:
+
+The VFIO_BAR_LEN ioctl provides an easy way to determine the size of a PCI
+device's base address region. It is passed a single integer specifying which
+BAR (0-5 or 6 for ROM bar), and passes back the length in the same field.
@@ -111,4 +111,6 @@ source "drivers/xen/Kconfig"
source "drivers/staging/Kconfig"
source "drivers/platform/Kconfig"
+
+source "drivers/vfio/Kconfig"
endmenu
@@ -52,6 +52,7 @@ obj-$(CONFIG_FUSION) += message/
obj-$(CONFIG_FIREWIRE) += firewire/
obj-y += ieee1394/
obj-$(CONFIG_UIO) += uio/
+obj-$(CONFIG_VFIO) += vfio/
obj-y += cdrom/
obj-y += auxdisplay/
obj-$(CONFIG_PCCARD) += pcmcia/
@@ -0,0 +1,9 @@
+menuconfig VFIO
+ tristate "Non-Priv User Space PCI drivers"
+ depends on PCI
+ help
+ Driver to allow advanced user space drivers for PCI, PCI-X,
+ and PCIe devices. Requires IOMMU to allow non-privilged
+ processes to directly control the PCI devices.
+
+ If you don't know what to do here, say N.
@@ -0,0 +1,5 @@
+obj-$(CONFIG_VFIO) := vfio.o
+
+vfio-y := vfio_main.o vfio_dma.o vfio_intrs.o \
+ vfio_pci_config.o vfio_rdwr.o vfio_sysfs.o
+
@@ -0,0 +1,372 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/mm.h>
+#include <linux/mmu_notifier.h>
+#include <linux/iommu.h>
+#include <linux/sched.h>
+
+#include <linux/vfio.h>
+
+/* Unmap DMA region */
+static void vfio_dma_unmap(struct vfio_listener *listener,
+ struct dma_map_page *mlp)
+{
+ int i;
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+
+ mutex_lock(&vdev->gate);
+ list_del(&mlp->list);
+ if (mlp->sg) {
+ dma_unmap_sg(&pdev->dev, mlp->sg, mlp->npage,
+ DMA_BIDIRECTIONAL);
+ kfree(mlp->sg);
+ } else {
+ for (i = 0; i < mlp->npage; i++)
+ (void) iommu_unmap_range(vdev->domain,
+ mlp->daddr + i*PAGE_SIZE, PAGE_SIZE);
+ }
+ for (i = 0; i < mlp->npage; i++) {
+ if (mlp->rdwr)
+ SetPageDirty(mlp->pages[i]);
+ put_page(mlp->pages[i]);
+ }
+ listener->mm->locked_vm -= mlp->npage;
+ vdev->locked_pages -= mlp->npage;
+ kfree(mlp->pages);
+ kfree(mlp);
+ vdev->mapcount--;
+ mutex_unlock(&vdev->gate);
+}
+
+/* Unmap ALL DMA regions */
+void vfio_dma_unmapall(struct vfio_listener *listener)
+{
+ struct list_head *pos, *pos2;
+ struct dma_map_page *mlp;
+
+ list_for_each_safe(pos, pos2, &listener->dm_list) {
+ mlp = list_entry(pos, struct dma_map_page, list);
+ vfio_dma_unmap(listener, mlp);
+ }
+}
+
+int vfio_dma_unmap_dm(struct vfio_listener *listener, struct vfio_dma_map *dmp)
+{
+ unsigned long start, npage;
+ struct dma_map_page *mlp;
+ struct list_head *pos, *pos2;
+ int ret;
+
+ start = dmp->vaddr & ~PAGE_SIZE;
+ npage = dmp->size >> PAGE_SHIFT;
+
+ ret = -ENXIO;
+ list_for_each_safe(pos, pos2, &listener->dm_list) {
+ mlp = list_entry(pos, struct dma_map_page, list);
+ if (dmp->vaddr != mlp->vaddr || mlp->npage != npage)
+ continue;
+ ret = 0;
+ vfio_dma_unmap(listener, mlp);
+ break;
+ }
+ return ret;
+}
+
+/* Handle MMU notifications - user process freed or realloced memory
+ * which may be in use in a DMA region. Clean up region if so.
+ */
+static void vfio_dma_handle_mmu_notify(struct mmu_notifier *mn,
+ unsigned long start, unsigned long end)
+{
+ struct vfio_listener *listener;
+ unsigned long myend;
+ struct list_head *pos, *pos2;
+ struct dma_map_page *mlp;
+
+ listener = container_of(mn, struct vfio_listener, mmu_notifier);
+ list_for_each_safe(pos, pos2, &listener->dm_list) {
+ mlp = list_entry(pos, struct dma_map_page, list);
+ if (mlp->vaddr >= end)
+ continue;
+ /*
+ * Ranges overlap if they're not disjoint; and they're
+ * disjoint if the end of one is before the start of
+ * the other one.
+ */
+ myend = mlp->vaddr + (mlp->npage << PAGE_SHIFT) - 1;
+ if (!(myend <= start || end <= mlp->vaddr)) {
+ printk(KERN_WARNING
+ "%s: demap start %lx end %lx va %lx pa %lx\n",
+ __func__, start, end,
+ mlp->vaddr, (long)mlp->daddr);
+ vfio_dma_unmap(listener, mlp);
+ }
+ }
+}
+
+static void vfio_dma_inval_page(struct mmu_notifier *mn,
+ struct mm_struct *mm, unsigned long addr)
+{
+ vfio_dma_handle_mmu_notify(mn, addr, addr + PAGE_SIZE);
+}
+
+static void vfio_dma_inval_range_start(struct mmu_notifier *mn,
+ struct mm_struct *mm, unsigned long start, unsigned long end)
+{
+ vfio_dma_handle_mmu_notify(mn, start, end);
+}
+
+static const struct mmu_notifier_ops vfio_dma_mmu_notifier_ops = {
+ .invalidate_page = vfio_dma_inval_page,
+ .invalidate_range_start = vfio_dma_inval_range_start,
+};
+
+/*
+ * Map usr buffer at specific IO virtual address
+ */
+static int vfio_dma_map_iova(
+ struct vfio_listener *listener,
+ unsigned long start_iova,
+ struct page **pages,
+ int npage,
+ int rdwr,
+ struct dma_map_page **mlpp)
+{
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+ int ret;
+ int i;
+ phys_addr_t hpa;
+ struct dma_map_page *mlp;
+ unsigned long iova = start_iova;
+
+ if (vdev->domain == NULL) {
+ /* can't mix iova with anywhere */
+ if (vdev->mapcount > 0)
+ return -EINVAL;
+ if (!iommu_found())
+ return -EINVAL;
+ vdev->domain = iommu_domain_alloc();
+ if (vdev->domain == NULL)
+ return -ENXIO;
+ vdev->cachec = iommu_domain_has_cap(vdev->domain,
+ IOMMU_CAP_CACHE_COHERENCY);
+ ret = iommu_attach_device(vdev->domain, &pdev->dev);
+ if (ret) {
+ iommu_domain_free(vdev->domain);
+ vdev->domain = NULL;
+ printk(KERN_ERR "%s: device_attach failed %d\n",
+ __func__, ret);
+ return ret;
+ }
+ }
+ for (i = 0; i < npage; i++) {
+ if (iommu_iova_to_phys(vdev->domain, iova + i*PAGE_SIZE))
+ return -EBUSY;
+ }
+ rdwr = rdwr ? IOMMU_READ|IOMMU_WRITE : IOMMU_READ;
+ if (vdev->cachec)
+ rdwr |= IOMMU_CACHE;
+ for (i = 0; i < npage; i++) {
+ hpa = page_to_phys(pages[i]);
+ ret = iommu_map_range(vdev->domain, iova,
+ hpa, PAGE_SIZE, rdwr);
+ if (ret) {
+ while (--i > 0) {
+ iova -= PAGE_SIZE;
+ (void) iommu_unmap_range(vdev->domain,
+ iova, PAGE_SIZE);
+ }
+ return ret;
+ }
+ iova += PAGE_SIZE;
+ }
+
+ mlp = kzalloc(sizeof *mlp, GFP_KERNEL);
+ mlp->pages = pages;
+ mlp->daddr = start_iova;
+ mlp->npage = npage;
+ *mlpp = mlp;
+ return 0;
+}
+
+/*
+ * Map user buffer - return IO virtual address
+ */
+static int vfio_dma_map_anywhere(
+ struct vfio_listener *listener,
+ struct page **pages,
+ int npage,
+ int rdwr,
+ struct dma_map_page **mlpp)
+{
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+ struct scatterlist *sg, *nsg;
+ int i, nents;
+ struct dma_map_page *mlp;
+ unsigned long length;
+
+ if (vdev->domain) {
+ /* map anywhere and map iova don't mix */
+ if (vdev->mapcount > 0)
+ return -EINVAL;
+ iommu_domain_free(vdev->domain);
+ vdev->domain = NULL;
+ }
+ sg = kzalloc(npage * sizeof(struct scatterlist), GFP_KERNEL);
+ if (sg == NULL)
+ return -ENOMEM;
+ for (i = 0; i < npage; i++)
+ sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0);
+ nents = dma_map_sg(&pdev->dev, sg, npage,
+ rdwr ? DMA_BIDIRECTIONAL : DMA_TO_DEVICE);
+ /* The API for dma_map_sg suggests that it may squash together
+ * adjacent pages, but noone seems to really do that. So we squash
+ * it ourselves, because the user level wants a single buffer.
+ * This works if (a) there is an iommu, or (b) the user allocates
+ * large buffers from a huge page
+ */
+ nsg = sg;
+ for (i = 1; i < nents; i++) {
+ length = sg[i].dma_length;
+ sg[i].dma_length = 0;
+ if (sg[i].dma_address == (nsg->dma_address + nsg->dma_length)) {
+ nsg->dma_length += length;
+ } else {
+ nsg++;
+ nsg->dma_address = sg[i].dma_address;
+ nsg->dma_length = length;
+ }
+ }
+ nents = 1 + (nsg - sg);
+ if (nents != 1) {
+ if (nents > 0)
+ dma_unmap_sg(&pdev->dev, sg, npage,
+ DMA_BIDIRECTIONAL);
+ for (i = 0; i < npage; i++)
+ put_page(pages[i]);
+ kfree(sg);
+ printk(KERN_ERR "%s: sequential dma mapping failed\n",
+ __func__);
+ return -EFAULT;
+ }
+
+ mlp = kzalloc(sizeof *mlp, GFP_KERNEL);
+ mlp->pages = pages;
+ mlp->sg = sg;
+ mlp->daddr = sg_dma_address(sg);
+ mlp->npage = npage;
+ *mlpp = mlp;
+ return 0;
+}
+
+int vfio_dma_map_common(struct vfio_listener *listener,
+ unsigned int cmd, struct vfio_dma_map *dmp)
+{
+ int locked, lock_limit;
+ struct page **pages;
+ int npage;
+ struct dma_map_page *mlp = NULL;
+ int ret = 0;
+
+ if (dmp->vaddr & (PAGE_SIZE-1))
+ return -EINVAL;
+ if (dmp->size & (PAGE_SIZE-1))
+ return -EINVAL;
+ if (dmp->size <= 0)
+ return -EINVAL;
+ npage = dmp->size >> PAGE_SHIFT;
+
+ mutex_lock(&listener->vdev->gate);
+
+ /* account for locked pages */
+ locked = npage + current->mm->locked_vm;
+ lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur
+ >> PAGE_SHIFT;
+ if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
+ printk(KERN_WARNING "%s: RLIMIT_MEMLOCK exceeded\n",
+ __func__);
+ ret = -ENOMEM;
+ goto out_lock;
+ }
+ /* only 1 address space per fd */
+ if (current->mm != listener->mm) {
+ if (listener->mm != NULL)
+ return -EINVAL;
+ listener->mm = current->mm;
+ listener->mmu_notifier.ops = &vfio_dma_mmu_notifier_ops;
+ ret = mmu_notifier_register(&listener->mmu_notifier,
+ listener->mm);
+ if (ret)
+ printk(KERN_ERR "%s: mmu_notifier_register failed %d\n",
+ __func__, ret);
+ ret = 0;
+ }
+
+ pages = kzalloc(npage * sizeof(struct page *), GFP_KERNEL);
+ if (pages == NULL) {
+ ret = ENOMEM;
+ goto out_lock;
+ }
+ ret = get_user_pages_fast(dmp->vaddr, npage, dmp->rdwr, pages);
+ if (ret != npage) {
+ printk(KERN_ERR "%s: get_user_pages_fast returns %d, not %d\n",
+ __func__, ret, npage);
+ kfree(pages);
+ ret = -EFAULT;
+ goto out_lock;
+ }
+
+ if (cmd == VFIO_DMA_MAP_IOVA)
+ ret = vfio_dma_map_iova(listener, dmp->dmaaddr,
+ pages, npage, dmp->rdwr, &mlp);
+ else
+ ret = vfio_dma_map_anywhere(listener, pages,
+ npage, dmp->rdwr, &mlp);
+ if (ret) {
+ kfree(pages);
+ goto out_lock;
+ }
+ listener->vdev->mapcount++;
+ mlp->vaddr = dmp->vaddr;
+ mlp->rdwr = dmp->rdwr;
+ dmp->dmaaddr = mlp->daddr;
+ list_add(&mlp->list, &listener->dm_list);
+
+ current->mm->locked_vm += npage;
+ listener->vdev->locked_pages += npage;
+out_lock:
+ mutex_unlock(&listener->vdev->gate);
+ return ret;
+}
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/eventfd.h>
+#include <linux/pci.h>
+#include <linux/mmu_notifier.h>
+
+#include <linux/vfio.h>
+
+
+/*
+ * vfio_interrupt - IRQ hardware interrupt handler
+ */
+irqreturn_t vfio_interrupt(int irq, void *dev_id)
+{
+ struct vfio_dev *vdev = (struct vfio_dev *)dev_id;
+ struct pci_dev *pdev = vdev->pdev;
+ irqreturn_t ret = IRQ_NONE;
+ u32 cmd_status_dword;
+ u16 origcmd, newcmd, status;
+
+ spin_lock_irq(&vdev->lock);
+ pci_block_user_cfg_access(pdev);
+
+ /* Read both command and status registers in a single 32-bit operation.
+ * Note: we could cache the value for command and move the status read
+ * out of the lock if there was a way to get notified of user changes
+ * to command register through sysfs. Should be good for shared irqs. */
+ pci_read_config_dword(pdev, PCI_COMMAND, &cmd_status_dword);
+ origcmd = cmd_status_dword;
+ status = cmd_status_dword >> 16;
+
+ /* Check interrupt status register to see whether our device
+ * triggered the interrupt. */
+ if (!(status & PCI_STATUS_INTERRUPT))
+ goto done;
+
+ /* We triggered the interrupt, disable it. */
+ newcmd = origcmd | PCI_COMMAND_INTX_DISABLE;
+ if (newcmd != origcmd)
+ pci_write_config_word(pdev, PCI_COMMAND, newcmd);
+
+ ret = IRQ_HANDLED;
+done:
+ pci_unblock_user_cfg_access(pdev);
+ spin_unlock_irq(&vdev->lock);
+ if (ret != IRQ_HANDLED)
+ return ret;
+ if (vdev->ev_irq)
+ eventfd_signal(vdev->ev_irq, 1);
+ return ret;
+}
+
+/*
+ * MSI and MSI-X Interrupt handler.
+ * Just signal an event
+ */
+static irqreturn_t msihandler(int irq, void *arg)
+{
+ struct eventfd_ctx *ctx = arg;
+
+ eventfd_signal(ctx, 1);
+ return IRQ_HANDLED;
+}
+
+void vfio_disable_msi(struct vfio_dev *vdev)
+{
+ struct pci_dev *pdev = vdev->pdev;
+
+ if (vdev->ev_msi) {
+ eventfd_ctx_put(vdev->ev_msi);
+ free_irq(pdev->irq, vdev->ev_msi);
+ vdev->ev_msi = NULL;
+ }
+ pci_disable_msi(pdev);
+}
+
+int vfio_enable_msi(struct vfio_dev *vdev, int fd)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ struct eventfd_ctx *ctx;
+ int ret;
+
+ ctx = eventfd_ctx_fdget(fd);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+ vdev->ev_msi = ctx;
+ pci_enable_msi(pdev);
+ ret = request_irq(pdev->irq, msihandler, 0,
+ vdev->name, ctx);
+ if (ret) {
+ eventfd_ctx_put(ctx);
+ pci_disable_msi(pdev);
+ vdev->ev_msi = NULL;
+ }
+ return ret;
+}
+
+void vfio_disable_msix(struct vfio_dev *vdev)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ int i;
+
+ if (vdev->ev_msix && vdev->msix) {
+ for (i = 0; i < vdev->nvec; i++) {
+ free_irq(vdev->msix[i].vector, vdev->ev_msix[i]);
+ if (vdev->ev_msix[i])
+ eventfd_ctx_put(vdev->ev_msix[i]);
+ }
+ }
+ kfree(vdev->ev_msix);
+ vdev->ev_msix = NULL;
+ kfree(vdev->msix);
+ vdev->msix = NULL;
+ vdev->nvec = 0;
+ pci_disable_msix(pdev);
+}
+
+int vfio_enable_msix(struct vfio_dev *vdev, int nvec, void __user *uarg)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ struct eventfd_ctx *ctx;
+ int ret = 0;
+ int i;
+ int fd;
+
+ vdev->msix = kzalloc(nvec * sizeof(struct msix_entry),
+ GFP_KERNEL);
+ vdev->ev_msix = kzalloc(nvec * sizeof(struct eventfd_ctx *),
+ GFP_KERNEL);
+ if (vdev->msix == NULL || vdev->ev_msix == NULL)
+ ret = -ENOMEM;
+ else {
+ for (i = 0; i < nvec; i++) {
+ if (copy_from_user(&fd, uarg, sizeof fd)) {
+ ret = -EFAULT;
+ break;
+ }
+ uarg += sizeof fd;
+ ctx = eventfd_ctx_fdget(fd);
+ if (IS_ERR(ctx)) {
+ ret = PTR_ERR(ctx);
+ break;
+ }
+ vdev->msix[i].entry = i;
+ vdev->ev_msix[i] = ctx;
+ }
+ }
+ if (!ret)
+ ret = pci_enable_msix(pdev, vdev->msix, nvec);
+ vdev->nvec = 0;
+ for (i = 0; i < nvec && !ret; i++) {
+ ret = request_irq(vdev->msix[i].vector, msihandler, 0,
+ vdev->name, vdev->ev_msix[i]);
+ if (ret)
+ break;
+ vdev->nvec = i+1;
+ }
+ if (ret)
+ vfio_disable_msix(vdev);
+ return ret;
+}
@@ -0,0 +1,627 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/mm.h>
+#include <linux/idr.h>
+#include <linux/string.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/eventfd.h>
+#include <linux/pci.h>
+#include <linux/iommu.h>
+#include <linux/mmu_notifier.h>
+#include <linux/uaccess.h>
+
+#include <linux/vfio.h>
+
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "Tom Lyon <pugs@cisco.com>"
+#define DRIVER_DESC "VFIO - User Level PCI meta-driver"
+
+static int vfio_major = -1;
+DEFINE_IDR(vfio_idr);
+/* Protect idr accesses */
+DEFINE_MUTEX(vfio_minor_lock);
+
+/*
+ * Does [a1,b1) overlap [a2,b2) ?
+ */
+static inline int overlap(int a1, int b1, int a2, int b2)
+{
+ /*
+ * Ranges overlap if they're not disjoint; and they're
+ * disjoint if the end of one is before the start of
+ * the other one.
+ */
+ return !(b2 <= a1 || b1 <= a2);
+}
+
+static int vfio_open(struct inode *inode, struct file *filep)
+{
+ struct vfio_dev *vdev;
+ struct vfio_listener *listener;
+ int ret = 0;
+
+ mutex_lock(&vfio_minor_lock);
+ vdev = idr_find(&vfio_idr, iminor(inode));
+ mutex_unlock(&vfio_minor_lock);
+ if (!vdev) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ listener = kzalloc(sizeof(*listener), GFP_KERNEL);
+ if (!listener) {
+ ret = -ENOMEM;
+ goto err_alloc_listener;
+ }
+
+ listener->vdev = vdev;
+ INIT_LIST_HEAD(&listener->dm_list);
+ filep->private_data = listener;
+
+ mutex_lock(&vdev->gate);
+ if (vdev->listeners == 0) { /* first open */
+ if (vdev->pmaster && !iommu_found() &&
+ !capable(CAP_SYS_RAWIO)) {
+ mutex_unlock(&vdev->gate);
+ ret = -EPERM;
+ goto err_perm;
+ }
+ /* reset to known state if we can */
+ (void) pci_reset_function(vdev->pdev);
+ }
+ vdev->listeners++;
+ mutex_unlock(&vdev->gate);
+ return 0;
+
+err_perm:
+ kfree(listener);
+
+err_alloc_listener:
+out:
+ return ret;
+}
+
+static int vfio_release(struct inode *inode, struct file *filep)
+{
+ int ret = 0;
+ struct vfio_listener *listener = filep->private_data;
+ struct vfio_dev *vdev = listener->vdev;
+
+ vfio_dma_unmapall(listener);
+ if (listener->mm) {
+ mmu_notifier_unregister(&listener->mmu_notifier, listener->mm);
+ listener->mm = NULL;
+ }
+
+ mutex_lock(&vdev->gate);
+ if (--vdev->listeners <= 0) {
+ if (vdev->ev_msix)
+ vfio_disable_msix(vdev);
+ if (vdev->ev_msi)
+ vfio_disable_msi(vdev);
+ if (vdev->ev_irq) {
+ eventfd_ctx_put(vdev->ev_msi);
+ vdev->ev_irq = NULL;
+ }
+ if (vdev->domain) {
+ iommu_domain_free(vdev->domain);
+ vdev->domain = NULL;
+ }
+ /* reset to known state if we can */
+ (void) pci_reset_function(vdev->pdev);
+ }
+ mutex_unlock(&vdev->gate);
+
+ kfree(listener);
+ return ret;
+}
+
+static ssize_t vfio_read(struct file *filep, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct vfio_listener *listener = filep->private_data;
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+ int pci_space;
+
+ pci_space = vfio_offset_to_pci_space(*ppos);
+ if (pci_space == VFIO_PCI_CONFIG_RESOURCE)
+ return vfio_config_readwrite(0, vdev, buf, count, ppos);
+ if (pci_space > PCI_ROM_RESOURCE)
+ return -EINVAL;
+ if (pci_resource_flags(pdev, pci_space) & IORESOURCE_IO)
+ return vfio_io_readwrite(0, vdev, buf, count, ppos);
+ if (pci_resource_flags(pdev, pci_space) & IORESOURCE_MEM)
+ return vfio_mem_readwrite(0, vdev, buf, count, ppos);
+ if (pci_space == PCI_ROM_RESOURCE)
+ return vfio_mem_readwrite(0, vdev, buf, count, ppos);
+ return -EINVAL;
+}
+
+static int vfio_msix_check(struct vfio_dev *vdev, u64 start, u32 len)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ u16 pos;
+ u32 table_offset;
+ u16 table_size;
+ u8 bir;
+ u32 lo, hi, startp, endp;
+
+ pos = pci_find_capability(pdev, PCI_CAP_ID_MSIX);
+ if (!pos)
+ return 0;
+
+ pci_read_config_word(pdev, pos + PCI_MSIX_FLAGS, &table_size);
+ table_size = (table_size & PCI_MSIX_FLAGS_QSIZE) + 1;
+ pci_read_config_dword(pdev, pos + 4, &table_offset);
+ bir = table_offset & PCI_MSIX_FLAGS_BIRMASK;
+ lo = table_offset >> PAGE_SHIFT;
+ hi = (table_offset + PCI_MSIX_ENTRY_SIZE * table_size + PAGE_SIZE - 1)
+ >> PAGE_SHIFT;
+ startp = start >> PAGE_SHIFT;
+ endp = (start + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ if (bir == vfio_offset_to_pci_space(start) &&
+ overlap(lo, hi, startp, endp)) {
+ printk(KERN_WARNING "%s: cannot write msi-x vectors\n",
+ __func__);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static ssize_t vfio_write(struct file *filep, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct vfio_listener *listener = filep->private_data;
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+ int pci_space;
+ int ret;
+
+ pci_space = vfio_offset_to_pci_space(*ppos);
+ if (pci_space == VFIO_PCI_CONFIG_RESOURCE)
+ return vfio_config_readwrite(1, vdev,
+ (char __user *)buf, count, ppos);
+ if (pci_space > PCI_ROM_RESOURCE)
+ return -EINVAL;
+ if (pci_resource_flags(pdev, pci_space) & IORESOURCE_IO)
+ return vfio_io_readwrite(1, vdev,
+ (char __user *)buf, count, ppos);
+ if (pci_resource_flags(pdev, pci_space) & IORESOURCE_MEM) {
+ /* don't allow writes to msi-x vectors */
+ ret = vfio_msix_check(vdev, *ppos, count);
+ if (ret)
+ return ret;
+ return vfio_mem_readwrite(1, vdev,
+ (char __user *)buf, count, ppos);
+ }
+ return -EINVAL;
+}
+
+static int vfio_mmap(struct file *filep, struct vm_area_struct *vma)
+{
+ struct vfio_listener *listener = filep->private_data;
+ struct vfio_dev *vdev = listener->vdev;
+ struct pci_dev *pdev = vdev->pdev;
+ unsigned long requested, actual;
+ int pci_space;
+ u64 start;
+ u32 len;
+ unsigned long phys;
+ int ret;
+
+ if (vma->vm_end < vma->vm_start)
+ return -EINVAL;
+ if ((vma->vm_flags & VM_SHARED) == 0)
+ return -EINVAL;
+
+
+ pci_space = vfio_offset_to_pci_space((u64)vma->vm_pgoff << PAGE_SHIFT);
+ if (pci_space > PCI_ROM_RESOURCE)
+ return -EINVAL;
+ switch (pci_space) {
+ case PCI_ROM_RESOURCE:
+ if (vma->vm_flags & VM_WRITE)
+ return -EINVAL;
+ if (pci_resource_flags(pdev, PCI_ROM_RESOURCE) == 0)
+ return -EINVAL;
+ actual = pci_resource_len(pdev, PCI_ROM_RESOURCE) >> PAGE_SHIFT;
+ break;
+ default:
+ if ((pci_resource_flags(pdev, pci_space) & IORESOURCE_MEM) == 0)
+ return -EINVAL;
+ actual = pci_resource_len(pdev, pci_space) >> PAGE_SHIFT;
+ break;
+ }
+
+ requested = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+ if (requested > actual || actual == 0)
+ return -EINVAL;
+
+ /*
+ * Can't allow non-priv users to mmap MSI-X vectors
+ * else they can write anywhere in phys memory
+ */
+ start = vma->vm_pgoff << PAGE_SHIFT;
+ len = vma->vm_end - vma->vm_start;
+ if (vma->vm_flags & VM_WRITE) {
+ ret = vfio_msix_check(vdev, start, len);
+ if (ret)
+ return ret;
+ }
+
+ vma->vm_private_data = vdev;
+ vma->vm_flags |= VM_IO | VM_RESERVED;
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ phys = pci_resource_start(pdev, pci_space) >> PAGE_SHIFT;
+
+ return remap_pfn_range(vma, vma->vm_start, phys,
+ vma->vm_end - vma->vm_start,
+ vma->vm_page_prot);
+}
+
+static long vfio_unl_ioctl(struct file *filep,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct vfio_listener *listener = filep->private_data;
+ struct vfio_dev *vdev = listener->vdev;
+ void __user *uarg = (void __user *)arg;
+ struct pci_dev *pdev = vdev->pdev;
+ struct vfio_dma_map dm;
+ int ret = 0;
+ u64 mask;
+ int fd, nfd;
+ int bar;
+
+ if (vdev == NULL)
+ return -EINVAL;
+
+ switch (cmd) {
+
+ case VFIO_DMA_MAP_ANYWHERE:
+ case VFIO_DMA_MAP_IOVA:
+ if (copy_from_user(&dm, uarg, sizeof dm))
+ return -EFAULT;
+ ret = vfio_dma_map_common(listener, cmd, &dm);
+ if (!ret && copy_to_user(uarg, &dm, sizeof dm))
+ ret = -EFAULT;
+ break;
+
+ case VFIO_DMA_UNMAP:
+ if (copy_from_user(&dm, uarg, sizeof dm))
+ return -EFAULT;
+ ret = vfio_dma_unmap_dm(listener, &dm);
+ break;
+
+ case VFIO_DMA_MASK: /* set master mode and DMA mask */
+ if (copy_from_user(&mask, uarg, sizeof mask))
+ return -EFAULT;
+ pci_set_master(pdev);
+ ret = pci_set_dma_mask(pdev, mask);
+ break;
+
+ case VFIO_EVENTFD_IRQ:
+ if (copy_from_user(&fd, uarg, sizeof fd))
+ return -EFAULT;
+ if (vdev->ev_irq)
+ eventfd_ctx_put(vdev->ev_irq);
+ if (fd >= 0) {
+ vdev->ev_irq = eventfd_ctx_fdget(fd);
+ if (vdev->ev_irq == NULL)
+ ret = -EINVAL;
+ }
+ break;
+
+ case VFIO_EVENTFD_MSI:
+ if (copy_from_user(&fd, uarg, sizeof fd))
+ return -EFAULT;
+ if (fd >= 0 && vdev->ev_msi == NULL && vdev->ev_msix == NULL)
+ ret = vfio_enable_msi(vdev, fd);
+ else if (fd < 0 && vdev->ev_msi)
+ vfio_disable_msi(vdev);
+ else
+ ret = -EINVAL;
+ break;
+
+ case VFIO_EVENTFDS_MSIX:
+ if (copy_from_user(&nfd, uarg, sizeof nfd))
+ return -EFAULT;
+ uarg += sizeof nfd;
+ if (nfd > 0 && vdev->ev_msi == NULL && vdev->ev_msix == NULL)
+ ret = vfio_enable_msix(vdev, nfd, uarg);
+ else if (nfd == 0 && vdev->ev_msix)
+ vfio_disable_msix(vdev);
+ else
+ ret = -EINVAL;
+ break;
+
+ case VFIO_BAR_LEN:
+ if (copy_from_user(&bar, uarg, sizeof bar))
+ return -EFAULT;
+ if (bar < 0 || bar > PCI_ROM_RESOURCE)
+ return -EINVAL;
+ bar = pci_resource_len(pdev, bar);
+ if (copy_to_user(uarg, &bar, sizeof bar))
+ return -EFAULT;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ return ret;
+}
+
+static const struct file_operations vfio_fops = {
+ .owner = THIS_MODULE,
+ .open = vfio_open,
+ .release = vfio_release,
+ .read = vfio_read,
+ .write = vfio_write,
+ .unlocked_ioctl = vfio_unl_ioctl,
+ .mmap = vfio_mmap,
+};
+
+static int vfio_get_devnum(struct vfio_dev *vdev)
+{
+ int retval = -ENOMEM;
+ int id;
+
+ mutex_lock(&vfio_minor_lock);
+ if (idr_pre_get(&vfio_idr, GFP_KERNEL) == 0)
+ goto exit;
+
+ retval = idr_get_new(&vfio_idr, vdev, &id);
+ if (retval < 0) {
+ if (retval == -EAGAIN)
+ retval = -ENOMEM;
+ goto exit;
+ }
+ if (id > MINORMASK) {
+ idr_remove(&vfio_idr, id);
+ retval = -ENOMEM;
+ }
+ if (vfio_major < 0) {
+ retval = register_chrdev(0, "vfio", &vfio_fops);
+ if (retval < 0)
+ goto exit;
+ vfio_major = retval;
+ }
+
+ retval = MKDEV(vfio_major, id);
+exit:
+ mutex_unlock(&vfio_minor_lock);
+ return retval;
+}
+
+static void vfio_free_minor(struct vfio_dev *vdev)
+{
+ mutex_lock(&vfio_minor_lock);
+ idr_remove(&vfio_idr, MINOR(vdev->devnum));
+ mutex_unlock(&vfio_minor_lock);
+}
+
+/*
+ * Verify that the device supports Interrupt Disable bit in command register,
+ * per PCI 2.3, by flipping this bit and reading it back: this bit was readonly
+ * in PCI 2.2. (from uio_pci_generic)
+ */
+static int verify_pci_2_3(struct pci_dev *pdev)
+{
+ u16 orig, new;
+ int err = 0;
+ u8 line;
+
+ pci_block_user_cfg_access(pdev);
+
+ pci_read_config_byte(pdev, PCI_INTERRUPT_LINE, &line);
+ if (line == 0)
+ goto out;
+
+ pci_read_config_word(pdev, PCI_COMMAND, &orig);
+ pci_write_config_word(pdev, PCI_COMMAND,
+ orig ^ PCI_COMMAND_INTX_DISABLE);
+ pci_read_config_word(pdev, PCI_COMMAND, &new);
+ /* There's no way to protect against
+ * hardware bugs or detect them reliably, but as long as we know
+ * what the value should be, let's go ahead and check it. */
+ if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
+ err = -EBUSY;
+ dev_err(&pdev->dev, "Command changed from 0x%x to 0x%x: "
+ "driver or HW bug?\n", orig, new);
+ goto out;
+ }
+ if (!((new ^ orig) & PCI_COMMAND_INTX_DISABLE)) {
+ dev_warn(&pdev->dev, "Device does not support "
+ "disabling interrupts: unable to bind.\n");
+ err = -ENODEV;
+ goto out;
+ }
+ /* Now restore the original value. */
+ pci_write_config_word(pdev, PCI_COMMAND, orig);
+out:
+ pci_unblock_user_cfg_access(pdev);
+ return err;
+}
+
+static int pci_is_master(struct pci_dev *pdev)
+{
+ int ret;
+ u16 orig, new;
+
+ if (pci_find_capability(pdev, PCI_CAP_ID_MSI))
+ return 1;
+ if (pci_find_capability(pdev, PCI_CAP_ID_MSIX))
+ return 1;
+
+ pci_block_user_cfg_access(pdev);
+
+ pci_read_config_word(pdev, PCI_COMMAND, &orig);
+ ret = orig & PCI_COMMAND_MASTER;
+ if (!ret) {
+ new = orig | PCI_COMMAND_MASTER;
+ pci_write_config_word(pdev, PCI_COMMAND, new);
+ pci_read_config_word(pdev, PCI_COMMAND, &new);
+ ret = new & PCI_COMMAND_MASTER;
+ pci_write_config_word(pdev, PCI_COMMAND, orig);
+ }
+
+ pci_unblock_user_cfg_access(pdev);
+ return ret;
+}
+
+static int vfio_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct vfio_dev *vdev;
+ int err;
+
+ err = pci_enable_device(pdev);
+ if (err) {
+ dev_err(&pdev->dev, "%s: pci_enable_device failed: %d\n",
+ __func__, err);
+ return err;
+ }
+
+ err = verify_pci_2_3(pdev);
+ if (err)
+ goto err_verify;
+
+ vdev = kzalloc(sizeof(struct vfio_dev), GFP_KERNEL);
+ if (!vdev) {
+ err = -ENOMEM;
+ goto err_alloc;
+ }
+ vdev->pdev = pdev;
+ vdev->pmaster = pci_is_master(pdev);
+
+ err = vfio_class_init();
+ if (err)
+ goto err_class;
+
+ mutex_init(&vdev->gate);
+
+ err = vfio_get_devnum(vdev);
+ if (err < 0)
+ goto err_get_devnum;
+ vdev->devnum = err;
+ err = 0;
+
+ sprintf(vdev->name, "vfio%d", MINOR(vdev->devnum));
+ pci_set_drvdata(pdev, vdev);
+ vdev->dev = device_create(vfio_class->class, &pdev->dev,
+ vdev->devnum, vdev, vdev->name);
+ if (IS_ERR(vdev->dev)) {
+ printk(KERN_ERR "VFIO: device register failed\n");
+ err = PTR_ERR(vdev->dev);
+ goto err_device_create;
+ }
+
+ err = vfio_dev_add_attributes(vdev);
+ if (err)
+ goto err_vfio_dev_add_attributes;
+
+
+ if (pdev->irq > 0) {
+ err = request_irq(pdev->irq, vfio_interrupt,
+ IRQF_SHARED, "vfio", vdev);
+ if (err)
+ goto err_request_irq;
+ }
+ vdev->vinfo.bardirty = 1;
+
+ return 0;
+
+err_request_irq:
+#ifdef notdef
+ vfio_dev_del_attributes(vdev);
+#endif
+err_vfio_dev_add_attributes:
+ device_destroy(vfio_class->class, vdev->devnum);
+err_device_create:
+ vfio_free_minor(vdev);
+err_get_devnum:
+err_class:
+ kfree(vdev);
+err_alloc:
+err_verify:
+ pci_disable_device(pdev);
+ return err;
+}
+
+static void vfio_remove(struct pci_dev *pdev)
+{
+ struct vfio_dev *vdev = pci_get_drvdata(pdev);
+
+ vfio_free_minor(vdev);
+
+ if (pdev->irq > 0)
+ free_irq(pdev->irq, vdev);
+
+#ifdef notdef
+ vfio_dev_del_attributes(vdev);
+#endif
+
+ pci_set_drvdata(pdev, NULL);
+ device_destroy(vfio_class->class, vdev->devnum);
+ kfree(vdev);
+ vfio_class_destroy();
+ pci_disable_device(pdev);
+}
+
+static struct pci_driver driver = {
+ .name = "vfio",
+ .id_table = NULL, /* only dynamic id's */
+ .probe = vfio_probe,
+ .remove = vfio_remove,
+};
+
+static int __init init(void)
+{
+ pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
+ return pci_register_driver(&driver);
+}
+
+static void __exit cleanup(void)
+{
+ if (vfio_major >= 0)
+ unregister_chrdev(vfio_major, "vfio");
+ pci_unregister_driver(&driver);
+}
+
+module_init(init);
+module_exit(cleanup);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
@@ -0,0 +1,554 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/mmu_notifier.h>
+#include <linux/uaccess.h>
+#include <linux/vfio.h>
+
+#define PCI_CAP_ID_BASIC 0
+#ifndef PCI_CAP_ID_MAX
+#define PCI_CAP_ID_MAX PCI_CAP_ID_AF
+#endif
+
+/*
+ * Lengths of PCI Config Capabilities
+ * 0 means unknown (but at least 4)
+ * FF means special/variable
+ */
+static u8 pci_capability_length[] = {
+ [PCI_CAP_ID_BASIC] = 64, /* pci config header */
+ [PCI_CAP_ID_PM] = PCI_PM_SIZEOF,
+ [PCI_CAP_ID_AGP] = PCI_AGP_SIZEOF,
+ [PCI_CAP_ID_VPD] = 8,
+ [PCI_CAP_ID_SLOTID] = 4,
+ [PCI_CAP_ID_MSI] = 0xFF, /* 10, 14, or 24 */
+ [PCI_CAP_ID_CHSWP] = 4,
+ [PCI_CAP_ID_PCIX] = 0xFF, /* 8 or 24 */
+ [PCI_CAP_ID_HT] = 28,
+ [PCI_CAP_ID_VNDR] = 0xFF,
+ [PCI_CAP_ID_DBG] = 0,
+ [PCI_CAP_ID_CCRC] = 0,
+ [PCI_CAP_ID_SHPC] = 0,
+ [PCI_CAP_ID_SSVID] = 0, /* bridge only - not supp */
+ [PCI_CAP_ID_AGP3] = 0,
+ [PCI_CAP_ID_EXP] = 36,
+ [PCI_CAP_ID_MSIX] = 12,
+ [PCI_CAP_ID_AF] = 6,
+};
+
+/*
+ * Read/Write Permission Bits - one bit for each bit in capability
+ * Any field can be read if it exists,
+ * but what is read depends on whether the field
+ * is 'virtualized', or just pass thru to the hardware.
+ * Any virtualized field is also virtualized for writes.
+ * Writes are only permitted if they have a 1 bit here.
+ */
+struct perm_bits {
+ u32 rvirt; /* read bits which must be virtualized */
+ u32 write; /* writeable bits - virt if read virt */
+};
+
+static struct perm_bits pci_cap_basic_perm[] = {
+ { 0xFFFFFFFF, 0, }, /* 0x00 vendor & device id - RO */
+ { 0, 0xFFFFFFFC, }, /* 0x04 cmd & status except mem/io */
+ { 0, 0xFF00FFFF, }, /* 0x08 bist, htype, lat, cache */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x0c bar */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x10 bar */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x14 bar */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x18 bar */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x1c bar */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x20 bar */
+ { 0, 0, }, /* 0x24 cardbus - not yet */
+ { 0, 0, }, /* 0x28 subsys vendor & dev */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x2c rom bar */
+ { 0, 0, }, /* 0x30 capability ptr & resv */
+ { 0, 0, }, /* 0x34 resv */
+ { 0, 0, }, /* 0x38 resv */
+ { 0x000000FF, 0x000000FF, }, /* 0x3c max_lat ... irq */
+};
+
+static struct perm_bits pci_cap_pm_perm[] = {
+ { 0, 0, }, /* 0x00 PM capabilities */
+ { 0, 0xFFFFFFFF, }, /* 0x04 PM control/status */
+};
+
+static struct perm_bits pci_cap_vpd_perm[] = {
+ { 0, 0xFFFF0000, }, /* 0x00 address */
+ { 0, 0xFFFFFFFF, }, /* 0x04 data */
+};
+
+static struct perm_bits pci_cap_slotid_perm[] = {
+ { 0, 0, }, /* 0x00 all read only */
+};
+
+static struct perm_bits pci_cap_msi_perm[] = {
+ { 0, 0, }, /* 0x00 MSI message control */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x04 MSI message address */
+ { 0xFFFFFFFF, 0xFFFFFFFF, }, /* 0x08 MSI message addr/data */
+ { 0x0000FFFF, 0x0000FFFF, }, /* 0x0c MSI message data */
+ { 0, 0xFFFFFFFF, }, /* 0x10 MSI mask bits */
+ { 0, 0xFFFFFFFF, }, /* 0x14 MSI pending bits */
+};
+
+static struct perm_bits pci_cap_pcix_perm[] = {
+ { 0, 0xFFFF0000, }, /* 0x00 PCI_X_CMD */
+ { 0, 0, }, /* 0x04 PCI_X_STATUS */
+ { 0, 0xFFFFFFFF, }, /* 0x08 ECC ctlr & status */
+ { 0, 0, }, /* 0x0c ECC first addr */
+ { 0, 0, }, /* 0x10 ECC second addr */
+ { 0, 0, }, /* 0x14 ECC attr */
+};
+
+/* pci express capabilities */
+static struct perm_bits pci_cap_exp_perm[] = {
+ { 0, 0, }, /* 0x00 PCIe capabilities */
+ { 0, 0, }, /* 0x04 PCIe device capabilities */
+ { 0, 0xFFFFFFFF, }, /* 0x08 PCIe device control & status */
+ { 0, 0, }, /* 0x0c PCIe link capabilities */
+ { 0, 0x000000FF, }, /* 0x10 PCIe link ctl/stat - SAFE? */
+ { 0, 0, }, /* 0x14 PCIe slot capabilities */
+ { 0, 0x00FFFFFF, }, /* 0x18 PCIe link ctl/stat - SAFE? */
+ { 0, 0, }, /* 0x1c PCIe root port stuff */
+ { 0, 0, }, /* 0x20 PCIe root port stuff */
+};
+
+static struct perm_bits pci_cap_msix_perm[] = {
+ { 0, 0, }, /* 0x00 MSI-X Enable */
+ { 0, 0, }, /* 0x04 table offset & bir */
+ { 0, 0, }, /* 0x08 pba offset & bir */
+};
+
+static struct perm_bits pci_cap_af_perm[] = {
+ { 0, 0, }, /* 0x00 af capability */
+ { 0, 0x0001, }, /* 0x04 af flr bit */
+};
+
+static struct perm_bits *pci_cap_perms[] = {
+ [PCI_CAP_ID_BASIC] = pci_cap_basic_perm,
+ [PCI_CAP_ID_PM] = pci_cap_pm_perm,
+ [PCI_CAP_ID_VPD] = pci_cap_vpd_perm,
+ [PCI_CAP_ID_SLOTID] = pci_cap_slotid_perm,
+ [PCI_CAP_ID_MSI] = pci_cap_msi_perm,
+ [PCI_CAP_ID_PCIX] = pci_cap_pcix_perm,
+ [PCI_CAP_ID_EXP] = pci_cap_exp_perm,
+ [PCI_CAP_ID_MSIX] = pci_cap_msix_perm,
+ [PCI_CAP_ID_AF] = pci_cap_af_perm,
+};
+
+/*
+ * We build a map of the config space that tells us where
+ * and what capabilities exist, so that we can map reads and
+ * writes back to capabilities, and thus figure out what to
+ * allow, deny, or virtualize
+ */
+int vfio_build_config_map(struct vfio_dev *vdev)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ u8 *map;
+ int i, len;
+ u8 pos, cap, tmp;
+ u16 flags;
+ int ret;
+ int loops = 100;
+
+ map = kmalloc(pdev->cfg_size, GFP_KERNEL);
+ if (map == NULL)
+ return -ENOMEM;
+ for (i = 0; i < pdev->cfg_size; i++)
+ map[i] = 0xFF;
+ vdev->pci_config_map = map;
+
+ /* default config space */
+ for (i = 0; i < pci_capability_length[0]; i++)
+ map[i] = 0;
+
+ /* any capabilities? */
+ ret = pci_read_config_word(pdev, PCI_STATUS, &flags);
+ if (ret < 0)
+ return ret;
+ if ((flags & PCI_STATUS_CAP_LIST) == 0)
+ return 0;
+
+ ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
+ if (ret < 0)
+ return ret;
+ while (pos && --loops > 0) {
+ ret = pci_read_config_byte(pdev, pos, &cap);
+ if (ret < 0)
+ return ret;
+ if (cap == 0) {
+ printk(KERN_WARNING "%s: cap 0\n", __func__);
+ break;
+ }
+ if (cap > PCI_CAP_ID_MAX) {
+ printk(KERN_WARNING "%s: unknown pci capability id %x\n",
+ __func__, cap);
+ len = 0;
+ } else
+ len = pci_capability_length[cap];
+ if (len == 0) {
+ printk(KERN_WARNING "%s: unknown length for pci cap %x\n",
+ __func__, cap);
+ len = 4;
+ }
+ if (len == 0xFF) {
+ switch (cap) {
+ case PCI_CAP_ID_MSI:
+ ret = pci_read_config_word(pdev,
+ pos + PCI_MSI_FLAGS, &flags);
+ if (ret < 0)
+ return ret;
+ if (flags & PCI_MSI_FLAGS_MASKBIT)
+ /* per vec masking */
+ len = 24;
+ else if (flags & PCI_MSI_FLAGS_64BIT)
+ /* 64 bit */
+ len = 14;
+ else
+ len = 10;
+ break;
+ case PCI_CAP_ID_PCIX:
+ ret = pci_read_config_word(pdev, pos + 2,
+ &flags);
+ if (ret < 0)
+ return ret;
+ if (flags & 0x3000)
+ len = 24;
+ else
+ len = 8;
+ break;
+ case PCI_CAP_ID_VNDR:
+ /* length follows next field */
+ ret = pci_read_config_byte(pdev, pos + 2, &tmp);
+ if (ret < 0)
+ return ret;
+ len = tmp;
+ break;
+ default:
+ len = 0;
+ break;
+ }
+ }
+
+ for (i = 0; i < len; i++) {
+ if (map[pos+i] != 0xFF)
+ printk(KERN_WARNING
+ "%s: pci config conflict at %x, "
+ "caps %x %x\n",
+ __func__, i, map[pos+i], cap);
+ map[pos+i] = cap;
+ }
+ ret = pci_read_config_byte(pdev, pos + PCI_CAP_LIST_NEXT, &pos);
+ if (ret < 0)
+ return ret;
+ }
+ if (loops <= 0)
+ printk(KERN_ERR "%s: config space loop!\n", __func__);
+ return 0;
+}
+
+static void vfio_virt_init(struct vfio_dev *vdev)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ int bar;
+ u32 *lp;
+ u32 val;
+ u8 *map, pos;
+ u16 flags;
+ int i, len;
+ int ret;
+
+ for (bar = 0; bar <= 5; bar++) {
+ lp = (u32 *)&vdev->vinfo.bar[bar * 4];
+ pci_read_config_dword(pdev, PCI_BASE_ADDRESS_0 + 4*bar, &val);
+ *lp++ = val;
+ }
+ lp = (u32 *)vdev->vinfo.rombar;
+ pci_read_config_dword(pdev, PCI_ROM_ADDRESS, &val);
+ *lp = val;
+
+ vdev->vinfo.intr = pdev->irq;
+
+ pos = pci_find_capability(pdev, PCI_CAP_ID_MSI);
+ map = vdev->pci_config_map + pos;
+ if (pos > 0) {
+ ret = pci_read_config_word(pdev, pos + PCI_MSI_FLAGS, &flags);
+ if (ret < 0)
+ return;
+ if (flags & PCI_MSI_FLAGS_MASKBIT) /* per vec masking */
+ len = 24;
+ else if (flags & PCI_MSI_FLAGS_64BIT) /* 64 bit */
+ len = 14;
+ else
+ len = 10;
+ for (i = 0; i < len; i++)
+ (void) pci_read_config_byte(pdev, pos + i,
+ &vdev->vinfo.msi[i]);
+ }
+}
+
+static void vfio_bar_fixup(struct vfio_dev *vdev)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ int bar;
+ u32 *lp;
+ u32 len;
+
+ for (bar = 0; bar <= 5; bar++) {
+ len = pci_resource_len(pdev, bar);
+ lp = (u32 *)&vdev->vinfo.bar[bar * 4];
+ if (len == 0) {
+ *lp = 0;
+ } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
+ *lp &= ~0x1;
+ *lp = (*lp & ~(len-1)) |
+ (*lp & ~PCI_BASE_ADDRESS_MEM_MASK);
+ if (*lp & PCI_BASE_ADDRESS_MEM_TYPE_64)
+ bar++;
+ } else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
+ *lp |= PCI_BASE_ADDRESS_SPACE_IO;
+ *lp = (*lp & ~(len-1)) |
+ (*lp & ~PCI_BASE_ADDRESS_IO_MASK);
+ }
+ }
+ lp = (u32 *)vdev->vinfo.rombar;
+ len = pci_resource_len(pdev, PCI_ROM_RESOURCE);
+ *lp = *lp & PCI_ROM_ADDRESS_MASK & ~(len-1);
+ vdev->vinfo.bardirty = 0;
+}
+
+static int vfio_config_rwbyte(int write,
+ struct vfio_dev *vdev,
+ int pos,
+ char __user *buf)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ u8 *map = vdev->pci_config_map;
+ u8 cap, val, newval;
+ u16 start, off;
+ int p;
+ struct perm_bits *perm;
+ u8 wr, virt;
+ int ret;
+
+ cap = map[pos];
+ if (cap == 0xFF) { /* unknown region */
+ if (write)
+ return 0; /* silent no-op */
+ val = 0;
+ if (pos <= pci_capability_length[0]) /* ok to read */
+ (void) pci_read_config_byte(pdev, pos, &val);
+ if (copy_to_user(buf, &val, 1))
+ return -EFAULT;
+ return 0;
+ }
+
+ /* scan back to start of cap region */
+ for (p = pos; p >= 0; p--) {
+ if (map[p] != cap)
+ break;
+ start = p;
+ }
+ off = pos - start; /* offset within capability */
+
+ perm = pci_cap_perms[cap];
+ if (perm == NULL) {
+ wr = 0;
+ virt = 0;
+ } else {
+ perm += (off >> 2);
+ wr = perm->write >> ((off & 3) * 8);
+ virt = perm->rvirt >> ((off & 3) * 8);
+ }
+ if (write && !wr) /* no writeable bits */
+ return 0;
+ if (!virt) {
+ if (write) {
+ if (copy_from_user(&val, buf, 1))
+ return -EFAULT;
+ val &= wr;
+ if (wr != 0xFF) {
+ u8 existing;
+
+ ret = pci_read_config_byte(pdev, pos,
+ &existing);
+ if (ret < 0)
+ return ret;
+ val |= (existing & ~wr);
+ }
+ pci_write_config_byte(pdev, pos, val);
+ } else {
+ ret = pci_read_config_byte(pdev, pos, &val);
+ if (ret < 0)
+ return ret;
+ if (copy_to_user(buf, &val, 1))
+ return -EFAULT;
+ }
+ return 0;
+ }
+
+ if (write) {
+ if (copy_from_user(&newval, buf, 1))
+ return -EFAULT;
+ }
+ /*
+ * We get here if there are some virt bits
+ * handle remaining real bits, if any
+ */
+ if (~virt) {
+ u8 rbits = (~virt) & wr;
+
+ ret = pci_read_config_byte(pdev, pos, &val);
+ if (ret < 0)
+ return ret;
+ if (write && rbits) {
+ val &= ~rbits;
+ newval &= rbits;
+ val |= newval;
+ pci_write_config_byte(pdev, pos, val);
+ }
+ }
+ /*
+ * Now handle entirely virtual fields
+ */
+ switch (cap) {
+ case PCI_CAP_ID_BASIC: /* virtualize BARs */
+ switch (off) {
+ /*
+ * vendor and device are virt because they don't
+ * show up otherwise for sr-iov vfs
+ */
+ case PCI_VENDOR_ID:
+ val = pdev->vendor;
+ break;
+ case PCI_VENDOR_ID + 1:
+ val = pdev->vendor >> 8;
+ break;
+ case PCI_DEVICE_ID:
+ val = pdev->device;
+ break;
+ case PCI_DEVICE_ID + 1:
+ val = pdev->device >> 8;
+ break;
+ case PCI_INTERRUPT_LINE:
+ if (write)
+ vdev->vinfo.intr = newval;
+ else
+ val = vdev->vinfo.intr;
+ break;
+ case PCI_ROM_ADDRESS:
+ case PCI_ROM_ADDRESS+1:
+ case PCI_ROM_ADDRESS+2:
+ case PCI_ROM_ADDRESS+3:
+ if (write) {
+ vdev->vinfo.rombar[off & 3] = newval;
+ vdev->vinfo.bardirty = 1;
+ } else {
+ if (vdev->vinfo.bardirty)
+ vfio_bar_fixup(vdev);
+ val = vdev->vinfo.rombar[off & 3];
+ }
+ break;
+ default:
+ if (off >= PCI_BASE_ADDRESS_0 &&
+ off <= PCI_BASE_ADDRESS_5 + 3) {
+ int boff = off - PCI_BASE_ADDRESS_0;
+
+ if (write) {
+ vdev->vinfo.bar[boff] = newval;
+ vdev->vinfo.bardirty = 1;
+ } else {
+ if (vdev->vinfo.bardirty)
+ vfio_bar_fixup(vdev);
+ val = vdev->vinfo.bar[boff];
+ }
+ }
+ break;
+ }
+ break;
+ case PCI_CAP_ID_MSI: /* virtualize MSI */
+ if (off >= PCI_MSI_ADDRESS_LO && off <= (PCI_MSI_DATA_64 + 2)) {
+ int moff = off - PCI_MSI_ADDRESS_LO;
+
+ if (write)
+ vdev->vinfo.msi[moff] = newval;
+ else
+ val = vdev->vinfo.msi[moff];
+ break;
+ }
+ break;
+ }
+ if (!write && copy_to_user(buf, &val, 1))
+ return -EFAULT;
+ return 0;
+}
+
+ssize_t vfio_config_readwrite(int write,
+ struct vfio_dev *vdev,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ int done = 0;
+ int ret;
+ int pos;
+
+ pci_block_user_cfg_access(pdev);
+
+ if (vdev->pci_config_map == NULL) {
+ ret = vfio_build_config_map(vdev);
+ if (ret < 0)
+ goto out;
+ vfio_virt_init(vdev);
+ }
+
+ while (count > 0) {
+ pos = *ppos;
+ if (pos == pdev->cfg_size)
+ break;
+ if (pos > pdev->cfg_size) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = vfio_config_rwbyte(write, vdev, pos, buf);
+ if (ret < 0)
+ goto out;
+ buf++;
+ done++;
+ count--;
+ (*ppos)++;
+ }
+ ret = done;
+out:
+ pci_unblock_user_cfg_access(pdev);
+ return ret;
+}
@@ -0,0 +1,147 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/mmu_notifier.h>
+#include <linux/pci.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include <linux/vfio.h>
+
+ssize_t vfio_io_readwrite(
+ int write,
+ struct vfio_dev *vdev,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ size_t done = 0;
+ resource_size_t end;
+ void __iomem *io;
+ loff_t pos;
+ int pci_space;
+ int unit;
+
+ pci_space = vfio_offset_to_pci_space(*ppos);
+ pos = (*ppos & 0xFFFFFFFF);
+
+ if (vdev->bar[pci_space] == NULL)
+ vdev->bar[pci_space] = pci_iomap(pdev, pci_space, 0);
+ io = vdev->bar[pci_space];
+ end = pci_resource_len(pdev, pci_space);
+ if (pos + count > end)
+ return -EINVAL;
+
+ while (count > 0) {
+ if ((pos % 4) == 0 && count >= 4) {
+ u32 val;
+
+ if (write) {
+ if (copy_from_user(&val, buf, 4))
+ return -EFAULT;
+ iowrite32(val, io + pos);
+ } else {
+ val = ioread32(io + pos);
+ if (copy_to_user(buf, &val, 4))
+ return -EFAULT;
+ }
+ unit = 4;
+ } else if ((pos % 2) == 0 && count >= 2) {
+ u16 val;
+
+ if (write) {
+ if (copy_from_user(&val, buf, 2))
+ return -EFAULT;
+ iowrite16(val, io + pos);
+ } else {
+ val = ioread16(io + pos);
+ if (copy_to_user(buf, &val, 2))
+ return -EFAULT;
+ }
+ unit = 2;
+ } else {
+ u8 val;
+
+ if (write) {
+ if (copy_from_user(&val, buf, 1))
+ return -EFAULT;
+ iowrite8(val, io + pos);
+ } else {
+ val = ioread8(io + pos);
+ if (copy_to_user(buf, &val, 1))
+ return -EFAULT;
+ }
+ unit = 1;
+ }
+ pos += unit;
+ buf += unit;
+ count -= unit;
+ done += unit;
+ }
+ *ppos += done;
+ return done;
+}
+
+ssize_t vfio_mem_readwrite(
+ int write,
+ struct vfio_dev *vdev,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct pci_dev *pdev = vdev->pdev;
+ resource_size_t end;
+ void __iomem *io;
+ loff_t pos;
+ int pci_space;
+
+ pci_space = vfio_offset_to_pci_space(*ppos);
+ pos = (*ppos & 0xFFFFFFFF);
+
+ if (vdev->bar[pci_space] == NULL)
+ vdev->bar[pci_space] = pci_iomap(pdev, pci_space, 0);
+ io = vdev->bar[pci_space];
+ end = pci_resource_len(pdev, pci_space);
+ if (pos > end)
+ return -EINVAL;
+ if (pos == end)
+ return 0;
+ if (pos + count > end)
+ count = end - pos;
+ if (write) {
+ if (copy_from_user(io + pos, buf, count))
+ return -EFAULT;
+ } else {
+ if (copy_to_user(buf, io + pos, count))
+ return -EFAULT;
+ }
+ *ppos += count;
+ return count;
+}
@@ -0,0 +1,153 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+#include <linux/pci.h>
+#include <linux/mmu_notifier.h>
+
+#include <linux/vfio.h>
+
+struct vfio_class *vfio_class;
+
+int vfio_class_init(void)
+{
+ int ret = 0;
+
+ if (vfio_class != NULL) {
+ kref_get(&vfio_class->kref);
+ goto exit;
+ }
+
+ vfio_class = kzalloc(sizeof(*vfio_class), GFP_KERNEL);
+ if (!vfio_class) {
+ ret = -ENOMEM;
+ goto err_kzalloc;
+ }
+
+ kref_init(&vfio_class->kref);
+ vfio_class->class = class_create(THIS_MODULE, "vfio");
+ if (IS_ERR(vfio_class->class)) {
+ ret = IS_ERR(vfio_class->class);
+ printk(KERN_ERR "class_create failed for vfio\n");
+ goto err_class_create;
+ }
+ return 0;
+
+err_class_create:
+ kfree(vfio_class);
+ vfio_class = NULL;
+err_kzalloc:
+exit:
+ return ret;
+}
+
+static void vfio_class_release(struct kref *kref)
+{
+ /* Ok, we cheat as we know we only have one vfio_class */
+ class_destroy(vfio_class->class);
+ kfree(vfio_class);
+ vfio_class = NULL;
+}
+
+void vfio_class_destroy(void)
+{
+ if (vfio_class)
+ kref_put(&vfio_class->kref, vfio_class_release);
+}
+
+ssize_t config_map_read(struct kobject *kobj, struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct vfio_dev *vdev = bin_attr->private;
+ int ret;
+
+ if (off >= 256)
+ return 0;
+ if (off + count > 256)
+ count = 256 - off;
+ if (vdev->pci_config_map == NULL) {
+ ret = vfio_build_config_map(vdev);
+ if (ret < 0)
+ return ret;
+ }
+ memcpy(buf, vdev->pci_config_map + off, count);
+ return count;
+}
+
+static ssize_t show_locked_pages(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct vfio_dev *vdev = dev_get_drvdata(dev);
+
+ if (vdev == NULL)
+ return -ENODEV;
+ return sprintf(buf, "%u\n", vdev->locked_pages);
+}
+
+static DEVICE_ATTR(locked_pages, S_IRUGO, show_locked_pages, NULL);
+
+static struct attribute *vfio_attrs[] = {
+ &dev_attr_locked_pages.attr,
+ NULL,
+};
+
+static struct attribute_group vfio_attr_grp = {
+ .attrs = vfio_attrs,
+};
+
+struct bin_attribute config_map_bin_attribute = {
+ .attr = {
+ .name = "config_map",
+ .mode = S_IRUGO,
+ },
+ .size = 256,
+ .read = config_map_read,
+};
+
+int vfio_dev_add_attributes(struct vfio_dev *vdev)
+{
+ struct bin_attribute *bi;
+ int ret;
+
+ ret = sysfs_create_group(&vdev->dev->kobj, &vfio_attr_grp);
+ if (ret)
+ return ret;
+ bi = kmalloc(sizeof(*bi), GFP_KERNEL);
+ if (bi == NULL)
+ return -ENOMEM;
+ *bi = config_map_bin_attribute;
+ bi->private = vdev;
+ return sysfs_create_bin_file(&vdev->dev->kobj, bi);
+}
@@ -0,0 +1,193 @@
+/*
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs@cisco.com
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Portions derived from drivers/uio/uio.c:
+ * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
+ * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
+ * Copyright(C) 2006, Hans J. Koch <hjk@linutronix.de>
+ * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
+ *
+ * Portions derived from drivers/uio/uio_pci_generic.c:
+ * Copyright (C) 2009 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ */
+
+/*
+ * VFIO driver - allow mapping and use of certain PCI devices
+ * in unprivileged user processes. (If IOMMU is present)
+ * Especially useful for Virtual Function parts of SR-IOV devices
+ */
+
+#ifdef __KERNEL__
+
+struct vfio_dev {
+ struct device *dev;
+ struct pci_dev *pdev;
+ u8 *pci_config_map;
+ int pci_config_size;
+ char name[8];
+ int devnum;
+ int pmaster;
+ void __iomem *bar[PCI_ROM_RESOURCE+1];
+ spinlock_t lock; /* guards command register accesses */
+ int listeners;
+ int mapcount;
+ u32 locked_pages;
+ struct mutex gate;
+ struct msix_entry *msix;
+ int nvec;
+ struct iommu_domain *domain;
+ int cachec;
+ struct eventfd_ctx *ev_irq;
+ struct eventfd_ctx *ev_msi;
+ struct eventfd_ctx **ev_msix;
+ struct {
+ u8 intr;
+ u8 bardirty;
+ u8 rombar[4];
+ u8 bar[6*4];
+ u8 msi[24];
+ } vinfo;
+};
+
+struct vfio_listener {
+ struct vfio_dev *vdev;
+ struct list_head dm_list;
+ struct mm_struct *mm;
+ struct mmu_notifier mmu_notifier;
+};
+
+/*
+ * Structure for keeping track of memory nailed down by the
+ * user for DMA
+ */
+struct dma_map_page {
+ struct list_head list;
+ struct page **pages;
+ struct scatterlist *sg;
+ dma_addr_t daddr;
+ unsigned long vaddr;
+ int npage;
+ int rdwr;
+};
+
+/* VFIO class infrastructure */
+struct vfio_class {
+ struct kref kref;
+ struct class *class;
+};
+extern struct vfio_class *vfio_class;
+
+ssize_t vfio_io_readwrite(int, struct vfio_dev *,
+ char __user *, size_t, loff_t *);
+ssize_t vfio_mem_readwrite(int, struct vfio_dev *,
+ char __user *, size_t, loff_t *);
+ssize_t vfio_config_readwrite(int, struct vfio_dev *,
+ char __user *, size_t, loff_t *);
+
+void vfio_disable_msi(struct vfio_dev *);
+void vfio_disable_msix(struct vfio_dev *);
+int vfio_enable_msi(struct vfio_dev *, int);
+int vfio_enable_msix(struct vfio_dev *, int, void __user *);
+
+#ifndef PCI_MSIX_ENTRY_SIZE
+#define PCI_MSIX_ENTRY_SIZE 16
+#endif
+#ifndef PCI_STATUS_INTERRUPT
+#define PCI_STATUS_INTERRUPT 0x08
+#endif
+
+struct vfio_dma_map;
+void vfio_dma_unmapall(struct vfio_listener *);
+int vfio_dma_unmap_dm(struct vfio_listener *, struct vfio_dma_map *);
+int vfio_dma_map_common(struct vfio_listener *, unsigned int,
+ struct vfio_dma_map *);
+
+int vfio_class_init(void);
+void vfio_class_destroy(void);
+int vfio_dev_add_attributes(struct vfio_dev *);
+extern struct idr vfio_idr;
+extern struct mutex vfio_minor_lock;
+int vfio_build_config_map(struct vfio_dev *);
+
+irqreturn_t vfio_interrupt(int, void *);
+
+#endif /* __KERNEL__ */
+
+/* Kernel & User level defines for ioctls */
+
+/*
+ * Structure for DMA mapping of user buffers
+ * vaddr, dmaaddr, and size must all be page aligned
+ * buffer may only be larger than 1 page if (a) there is
+ * an iommu in the system, or (b) buffer is part of a huge page
+ */
+struct vfio_dma_map {
+ __u64 vaddr; /* process virtual addr */
+ __u64 dmaaddr; /* desired and/or returned dma address */
+ __u64 size; /* size in bytes */
+ int rdwr; /* bool: 0 for r/o; 1 for r/w */
+};
+
+/* map user pages at any dma address */
+#define VFIO_DMA_MAP_ANYWHERE _IOWR(';', 100, struct vfio_dma_map)
+
+/* map user pages at specific dma address */
+#define VFIO_DMA_MAP_IOVA _IOWR(';', 101, struct vfio_dma_map)
+
+/* unmap user pages */
+#define VFIO_DMA_UNMAP _IOW(';', 102, struct vfio_dma_map)
+
+/* set device DMA mask & master status */
+#define VFIO_DMA_MASK _IOW(';', 103, __u64)
+
+/* request IRQ interrupts; use given eventfd */
+#define VFIO_EVENTFD_IRQ _IOW(';', 104, int)
+
+/* request MSI interrupts; use given eventfd */
+#define VFIO_EVENTFD_MSI _IOW(';', 105, int)
+
+/* Request MSI-X interrupts: arg[0] is #, arg[1-n] are eventfds */
+#define VFIO_EVENTFDS_MSIX _IOW(';', 106, int)
+
+/* Get length of a BAR */
+#define VFIO_BAR_LEN _IOWR(';', 107, __u32)
+
+/*
+ * Reads, writes, and mmaps determine which PCI BAR (or config space)
+ * from the high level bits of the file offset
+ */
+#define VFIO_PCI_BAR0_RESOURCE 0x0
+#define VFIO_PCI_BAR1_RESOURCE 0x1
+#define VFIO_PCI_BAR2_RESOURCE 0x2
+#define VFIO_PCI_BAR3_RESOURCE 0x3
+#define VFIO_PCI_BAR4_RESOURCE 0x4
+#define VFIO_PCI_BAR5_RESOURCE 0x5
+#define VFIO_PCI_ROM_RESOURCE 0x6
+#define VFIO_PCI_CONFIG_RESOURCE 0xF
+#define VFIO_PCI_SPACE_SHIFT 32
+#define VFIO_PCI_CONFIG_OFF vfio_pci_space_to_offset(VFIO_PCI_CONFIG_RESOURCE)
+
+static inline int vfio_offset_to_pci_space(__u64 off)
+{
+ return (off >> VFIO_PCI_SPACE_SHIFT) & 0xF;
+}
+
+static __u64 vfio_pci_space_to_offset(int sp)
+{
+ return (__u64)(sp) << VFIO_PCI_SPACE_SHIFT;
+}
@@ -5968,6 +5968,13 @@ S: Maintained
F: Documentation/fb/uvesafb.txt
F: drivers/video/uvesafb.*
+VFIO DRIVER
+M: Tom Lyon <pugs@cisco.com>
+S: Supported
+F: Documentation/vfio.txt
+F: drivers/vfio/
+F: include/linux/vfio.h
+
VFAT/FAT/MSDOS FILESYSTEM
M: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
S: Maintained