WSL2-Linux-Kernel/drivers/char/drm/drm_pci.c

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/* 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 Jose Fonseca <jrfonseca@tungstengraphics.com>
* \author Leif Delgass <ldelgass@retinalburn.net>
*/
/*
* Copyright 2003 Jos<6F>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/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(drm_device_t * dev, size_t size, size_t align,
dma_addr_t maxaddr)
{
drm_dma_handle_t *dmah;
#if 1
unsigned long addr;
size_t sz;
#endif
#ifdef DRM_DEBUG_MEMORY
int area = DRM_MEM_DMA;
spin_lock(&drm_mem_lock);
if ((drm_ram_used >> PAGE_SHIFT)
> (DRM_RAM_PERCENT * drm_ram_available) / 100) {
spin_unlock(&drm_mem_lock);
return 0;
}
spin_unlock(&drm_mem_lock);
#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;
if (pci_set_dma_mask(dev->pdev, maxaddr) != 0) {
DRM_ERROR("Setting pci dma mask failed\n");
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);
#ifdef DRM_DEBUG_MEMORY
if (dmah->vaddr == NULL) {
spin_lock(&drm_mem_lock);
++drm_mem_stats[area].fail_count;
spin_unlock(&drm_mem_lock);
kfree(dmah);
return NULL;
}
spin_lock(&drm_mem_lock);
++drm_mem_stats[area].succeed_count;
drm_mem_stats[area].bytes_allocated += size;
drm_ram_used += size;
spin_unlock(&drm_mem_lock);
#else
if (dmah->vaddr == NULL) {
kfree(dmah);
return NULL;
}
#endif
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(drm_device_t * dev, drm_dma_handle_t * dmah)
{
#if 1
unsigned long addr;
size_t sz;
#endif
#ifdef DRM_DEBUG_MEMORY
int area = DRM_MEM_DMA;
int alloc_count;
int free_count;
#endif
if (!dmah->vaddr) {
#ifdef DRM_DEBUG_MEMORY
DRM_MEM_ERROR(area, "Attempt to free address 0\n");
#endif
} else {
/* 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);
}
#ifdef DRM_DEBUG_MEMORY
spin_lock(&drm_mem_lock);
free_count = ++drm_mem_stats[area].free_count;
alloc_count = drm_mem_stats[area].succeed_count;
drm_mem_stats[area].bytes_freed += size;
drm_ram_used -= size;
spin_unlock(&drm_mem_lock);
if (free_count > alloc_count) {
DRM_MEM_ERROR(area,
"Excess frees: %d frees, %d allocs\n",
free_count, alloc_count);
}
#endif
}
/**
* \brief Free a PCI consistent memory block
*/
void drm_pci_free(drm_device_t * dev, drm_dma_handle_t * dmah)
{
__drm_pci_free(dev, dmah);
kfree(dmah);
}
EXPORT_SYMBOL(drm_pci_free);
/*@}*/