linux/drivers/gpu/drm/drm_pci.c
Dave Airlie 466e69b8b0 drm: move pci bus master enable into driver.
The current enabling of bus mastering in the drm midlayer allows a large
race condition under kexec. When a kexec'ed kernel re-enables bus mastering
for the GPU, previously setup dma blocks may cause writes to random pieces
of memory. On radeon the writeback mechanism can cause these sorts of issues.

This patch doesn't fix the problem, but it moves the bus master enable under
the individual drivers control so they can move enabling it until later in
their load cycle and close the race.

Fix for radeon kms driver will be in a follow-up patch.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-02-16 18:31:07 +00:00

467 lines
12 KiB
C

/* drm_pci.h -- PCI DMA memory management wrappers for DRM -*- linux-c -*- */
/**
* \file drm_pci.c
* \brief Functions and ioctls to manage PCI memory
*
* \warning These interfaces aren't stable yet.
*
* \todo Implement the remaining ioctl's for the PCI pools.
* \todo The wrappers here are so thin that they would be better off inlined..
*
* \author José Fonseca <jrfonseca@tungstengraphics.com>
* \author Leif Delgass <ldelgass@retinalburn.net>
*/
/*
* Copyright 2003 José Fonseca.
* Copyright 2003 Leif Delgass.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* 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 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.
*/
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include "drmP.h"
/**********************************************************************/
/** \name PCI memory */
/*@{*/
/**
* \brief Allocate a PCI consistent memory block, for DMA.
*/
drm_dma_handle_t *drm_pci_alloc(struct drm_device * dev, size_t size, size_t align)
{
drm_dma_handle_t *dmah;
#if 1
unsigned long addr;
size_t sz;
#endif
/* pci_alloc_consistent only guarantees alignment to the smallest
* PAGE_SIZE order which is greater than or equal to the requested size.
* Return NULL here for now to make sure nobody tries for larger alignment
*/
if (align > size)
return NULL;
dmah = kmalloc(sizeof(drm_dma_handle_t), GFP_KERNEL);
if (!dmah)
return NULL;
dmah->size = size;
dmah->vaddr = dma_alloc_coherent(&dev->pdev->dev, size, &dmah->busaddr, GFP_KERNEL | __GFP_COMP);
if (dmah->vaddr == NULL) {
kfree(dmah);
return NULL;
}
memset(dmah->vaddr, 0, size);
/* XXX - Is virt_to_page() legal for consistent mem? */
/* Reserve */
for (addr = (unsigned long)dmah->vaddr, sz = size;
sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
SetPageReserved(virt_to_page(addr));
}
return dmah;
}
EXPORT_SYMBOL(drm_pci_alloc);
/**
* \brief Free a PCI consistent memory block without freeing its descriptor.
*
* This function is for internal use in the Linux-specific DRM core code.
*/
void __drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
{
#if 1
unsigned long addr;
size_t sz;
#endif
if (dmah->vaddr) {
/* XXX - Is virt_to_page() legal for consistent mem? */
/* Unreserve */
for (addr = (unsigned long)dmah->vaddr, sz = dmah->size;
sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
}
dma_free_coherent(&dev->pdev->dev, dmah->size, dmah->vaddr,
dmah->busaddr);
}
}
/**
* \brief Free a PCI consistent memory block
*/
void drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
{
__drm_pci_free(dev, dmah);
kfree(dmah);
}
EXPORT_SYMBOL(drm_pci_free);
#ifdef CONFIG_PCI
static int drm_get_pci_domain(struct drm_device *dev)
{
#ifndef __alpha__
/* For historical reasons, drm_get_pci_domain() is busticated
* on most archs and has to remain so for userspace interface
* < 1.4, except on alpha which was right from the beginning
*/
if (dev->if_version < 0x10004)
return 0;
#endif /* __alpha__ */
return pci_domain_nr(dev->pdev->bus);
}
static int drm_pci_get_irq(struct drm_device *dev)
{
return dev->pdev->irq;
}
static const char *drm_pci_get_name(struct drm_device *dev)
{
struct pci_driver *pdriver = dev->driver->kdriver.pci;
return pdriver->name;
}
int drm_pci_set_busid(struct drm_device *dev, struct drm_master *master)
{
int len, ret;
struct pci_driver *pdriver = dev->driver->kdriver.pci;
master->unique_len = 40;
master->unique_size = master->unique_len;
master->unique = kmalloc(master->unique_size, GFP_KERNEL);
if (master->unique == NULL)
return -ENOMEM;
len = snprintf(master->unique, master->unique_len,
"pci:%04x:%02x:%02x.%d",
drm_get_pci_domain(dev),
dev->pdev->bus->number,
PCI_SLOT(dev->pdev->devfn),
PCI_FUNC(dev->pdev->devfn));
if (len >= master->unique_len) {
DRM_ERROR("buffer overflow");
ret = -EINVAL;
goto err;
} else
master->unique_len = len;
dev->devname =
kmalloc(strlen(pdriver->name) +
master->unique_len + 2, GFP_KERNEL);
if (dev->devname == NULL) {
ret = -ENOMEM;
goto err;
}
sprintf(dev->devname, "%s@%s", pdriver->name,
master->unique);
return 0;
err:
return ret;
}
int drm_pci_set_unique(struct drm_device *dev,
struct drm_master *master,
struct drm_unique *u)
{
int domain, bus, slot, func, ret;
const char *bus_name;
master->unique_len = u->unique_len;
master->unique_size = u->unique_len + 1;
master->unique = kmalloc(master->unique_size, GFP_KERNEL);
if (!master->unique) {
ret = -ENOMEM;
goto err;
}
if (copy_from_user(master->unique, u->unique, master->unique_len)) {
ret = -EFAULT;
goto err;
}
master->unique[master->unique_len] = '\0';
bus_name = dev->driver->bus->get_name(dev);
dev->devname = kmalloc(strlen(bus_name) +
strlen(master->unique) + 2, GFP_KERNEL);
if (!dev->devname) {
ret = -ENOMEM;
goto err;
}
sprintf(dev->devname, "%s@%s", bus_name,
master->unique);
/* Return error if the busid submitted doesn't match the device's actual
* busid.
*/
ret = sscanf(master->unique, "PCI:%d:%d:%d", &bus, &slot, &func);
if (ret != 3) {
ret = -EINVAL;
goto err;
}
domain = bus >> 8;
bus &= 0xff;
if ((domain != drm_get_pci_domain(dev)) ||
(bus != dev->pdev->bus->number) ||
(slot != PCI_SLOT(dev->pdev->devfn)) ||
(func != PCI_FUNC(dev->pdev->devfn))) {
ret = -EINVAL;
goto err;
}
return 0;
err:
return ret;
}
static int drm_pci_irq_by_busid(struct drm_device *dev, struct drm_irq_busid *p)
{
if ((p->busnum >> 8) != drm_get_pci_domain(dev) ||
(p->busnum & 0xff) != dev->pdev->bus->number ||
p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn))
return -EINVAL;
p->irq = dev->pdev->irq;
DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum,
p->irq);
return 0;
}
int drm_pci_agp_init(struct drm_device *dev)
{
if (drm_core_has_AGP(dev)) {
if (drm_pci_device_is_agp(dev))
dev->agp = drm_agp_init(dev);
if (drm_core_check_feature(dev, DRIVER_REQUIRE_AGP)
&& (dev->agp == NULL)) {
DRM_ERROR("Cannot initialize the agpgart module.\n");
return -EINVAL;
}
if (drm_core_has_MTRR(dev)) {
if (dev->agp)
dev->agp->agp_mtrr =
mtrr_add(dev->agp->agp_info.aper_base,
dev->agp->agp_info.aper_size *
1024 * 1024, MTRR_TYPE_WRCOMB, 1);
}
}
return 0;
}
static struct drm_bus drm_pci_bus = {
.bus_type = DRIVER_BUS_PCI,
.get_irq = drm_pci_get_irq,
.get_name = drm_pci_get_name,
.set_busid = drm_pci_set_busid,
.set_unique = drm_pci_set_unique,
.irq_by_busid = drm_pci_irq_by_busid,
.agp_init = drm_pci_agp_init,
};
/**
* Register.
*
* \param pdev - PCI device structure
* \param ent entry from the PCI ID table with device type flags
* \return zero on success or a negative number on failure.
*
* Attempt to gets inter module "drm" information. If we are first
* then register the character device and inter module information.
* Try and register, if we fail to register, backout previous work.
*/
int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
struct drm_driver *driver)
{
struct drm_device *dev;
int ret;
DRM_DEBUG("\n");
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
ret = pci_enable_device(pdev);
if (ret)
goto err_g1;
dev->pdev = pdev;
dev->dev = &pdev->dev;
dev->pci_device = pdev->device;
dev->pci_vendor = pdev->vendor;
#ifdef __alpha__
dev->hose = pdev->sysdata;
#endif
mutex_lock(&drm_global_mutex);
if ((ret = drm_fill_in_dev(dev, ent, driver))) {
printk(KERN_ERR "DRM: Fill_in_dev failed.\n");
goto err_g2;
}
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
pci_set_drvdata(pdev, dev);
ret = drm_get_minor(dev, &dev->control, DRM_MINOR_CONTROL);
if (ret)
goto err_g2;
}
if ((ret = drm_get_minor(dev, &dev->primary, DRM_MINOR_LEGACY)))
goto err_g3;
if (dev->driver->load) {
ret = dev->driver->load(dev, ent->driver_data);
if (ret)
goto err_g4;
}
/* setup the grouping for the legacy output */
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
ret = drm_mode_group_init_legacy_group(dev,
&dev->primary->mode_group);
if (ret)
goto err_g4;
}
list_add_tail(&dev->driver_item, &driver->device_list);
DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
driver->name, driver->major, driver->minor, driver->patchlevel,
driver->date, pci_name(pdev), dev->primary->index);
mutex_unlock(&drm_global_mutex);
return 0;
err_g4:
drm_put_minor(&dev->primary);
err_g3:
if (drm_core_check_feature(dev, DRIVER_MODESET))
drm_put_minor(&dev->control);
err_g2:
pci_disable_device(pdev);
err_g1:
kfree(dev);
mutex_unlock(&drm_global_mutex);
return ret;
}
EXPORT_SYMBOL(drm_get_pci_dev);
/**
* PCI device initialization. Called direct from modules at load time.
*
* \return zero on success or a negative number on failure.
*
* Initializes a drm_device structures,registering the
* stubs and initializing the AGP device.
*
* Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
* after the initialization for driver customization.
*/
int drm_pci_init(struct drm_driver *driver, struct pci_driver *pdriver)
{
struct pci_dev *pdev = NULL;
const struct pci_device_id *pid;
int i;
DRM_DEBUG("\n");
INIT_LIST_HEAD(&driver->device_list);
driver->kdriver.pci = pdriver;
driver->bus = &drm_pci_bus;
if (driver->driver_features & DRIVER_MODESET)
return pci_register_driver(pdriver);
/* If not using KMS, fall back to stealth mode manual scanning. */
for (i = 0; pdriver->id_table[i].vendor != 0; i++) {
pid = &pdriver->id_table[i];
/* Loop around setting up a DRM device for each PCI device
* matching our ID and device class. If we had the internal
* function that pci_get_subsys and pci_get_class used, we'd
* be able to just pass pid in instead of doing a two-stage
* thing.
*/
pdev = NULL;
while ((pdev =
pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
pid->subdevice, pdev)) != NULL) {
if ((pdev->class & pid->class_mask) != pid->class)
continue;
/* stealth mode requires a manual probe */
pci_dev_get(pdev);
drm_get_pci_dev(pdev, pid, driver);
}
}
return 0;
}
#else
int drm_pci_init(struct drm_driver *driver, struct pci_driver *pdriver)
{
return -1;
}
#endif
EXPORT_SYMBOL(drm_pci_init);
/*@}*/
void drm_pci_exit(struct drm_driver *driver, struct pci_driver *pdriver)
{
struct drm_device *dev, *tmp;
DRM_DEBUG("\n");
if (driver->driver_features & DRIVER_MODESET) {
pci_unregister_driver(pdriver);
} else {
list_for_each_entry_safe(dev, tmp, &driver->device_list, driver_item)
drm_put_dev(dev);
}
DRM_INFO("Module unloaded\n");
}
EXPORT_SYMBOL(drm_pci_exit);