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linux-next/drivers/gpu/drm/drm_pci.c
Dave Airlie b64c115eb2 drm: fix race between driver loading and userspace open.
Not 100% sure this is due to BKL removal, its most likely a combination
of that + userspace timing changes in udev/plymouth. The drm adds the sysfs
device before the driver has completed internal loading, this causes udev
to make the node and plymouth to open it before we've completed loading.

The proper solution is to delay the sysfs manipulation until later in loading
however this causes knock on issues with sysfs connector nodes, so we can use
the global mutex to serialise loading and userspace opens.

Reported-by: Toni Spets (hifi on #radeon)
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-14 20:39:04 +10:00

275 lines
7.2 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 "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
/**
* 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;
pci_set_master(pdev);
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 via drm_init at module 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_dev *pdev = NULL;
const struct pci_device_id *pid;
int i;
if (driver->driver_features & DRIVER_MODESET)
return pci_register_driver(&driver->pci_driver);
/* If not using KMS, fall back to stealth mode manual scanning. */
for (i = 0; driver->pci_driver.id_table[i].vendor != 0; i++) {
pid = &driver->pci_driver.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)
{
return -1;
}
#endif
/*@}*/