x86/amd_gart: remove the mapping_error dma_map_ops method

Return DMA_MAPPING_ERROR instead of the magic bad_dma_addr on a dma
mapping failure and let the core dma-mapping code handle the rest.

Remove the magic EMERGENCY_PAGES that the bad_dma_addr gets redirected to.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2018-11-21 19:20:44 +01:00
parent 608b9761a0
commit 9e8aa6b546

View File

@ -50,8 +50,6 @@ static unsigned long iommu_pages; /* .. and in pages */
static u32 *iommu_gatt_base; /* Remapping table */
static dma_addr_t bad_dma_addr;
/*
* If this is disabled the IOMMU will use an optimized flushing strategy
* of only flushing when an mapping is reused. With it true the GART is
@ -74,8 +72,6 @@ static u32 gart_unmapped_entry;
(((x) & 0xfffff000) | (((x) >> 32) << 4) | GPTE_VALID | GPTE_COHERENT)
#define GPTE_DECODE(x) (((x) & 0xfffff000) | (((u64)(x) & 0xff0) << 28))
#define EMERGENCY_PAGES 32 /* = 128KB */
#ifdef CONFIG_AGP
#define AGPEXTERN extern
#else
@ -184,14 +180,6 @@ static void iommu_full(struct device *dev, size_t size, int dir)
*/
dev_err(dev, "PCI-DMA: Out of IOMMU space for %lu bytes\n", size);
if (size > PAGE_SIZE*EMERGENCY_PAGES) {
if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
panic("PCI-DMA: Memory would be corrupted\n");
if (dir == PCI_DMA_TODEVICE || dir == PCI_DMA_BIDIRECTIONAL)
panic(KERN_ERR
"PCI-DMA: Random memory would be DMAed\n");
}
#ifdef CONFIG_IOMMU_LEAK
dump_leak();
#endif
@ -220,7 +208,7 @@ static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
int i;
if (unlikely(phys_mem + size > GART_MAX_PHYS_ADDR))
return bad_dma_addr;
return DMA_MAPPING_ERROR;
iommu_page = alloc_iommu(dev, npages, align_mask);
if (iommu_page == -1) {
@ -229,7 +217,7 @@ static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
if (panic_on_overflow)
panic("dma_map_area overflow %lu bytes\n", size);
iommu_full(dev, size, dir);
return bad_dma_addr;
return DMA_MAPPING_ERROR;
}
for (i = 0; i < npages; i++) {
@ -271,7 +259,7 @@ static void gart_unmap_page(struct device *dev, dma_addr_t dma_addr,
int npages;
int i;
if (dma_addr < iommu_bus_base + EMERGENCY_PAGES*PAGE_SIZE ||
if (dma_addr == DMA_MAPPING_ERROR ||
dma_addr >= iommu_bus_base + iommu_size)
return;
@ -315,7 +303,7 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
if (nonforced_iommu(dev, addr, s->length)) {
addr = dma_map_area(dev, addr, s->length, dir, 0);
if (addr == bad_dma_addr) {
if (addr == DMA_MAPPING_ERROR) {
if (i > 0)
gart_unmap_sg(dev, sg, i, dir, 0);
nents = 0;
@ -471,7 +459,7 @@ error:
iommu_full(dev, pages << PAGE_SHIFT, dir);
for_each_sg(sg, s, nents, i)
s->dma_address = bad_dma_addr;
s->dma_address = DMA_MAPPING_ERROR;
return 0;
}
@ -490,7 +478,7 @@ gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
*dma_addr = dma_map_area(dev, virt_to_phys(vaddr), size,
DMA_BIDIRECTIONAL, (1UL << get_order(size)) - 1);
flush_gart();
if (unlikely(*dma_addr == bad_dma_addr))
if (unlikely(*dma_addr == DMA_MAPPING_ERROR))
goto out_free;
return vaddr;
out_free:
@ -507,11 +495,6 @@ gart_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_direct_free_pages(dev, size, vaddr, dma_addr, attrs);
}
static int gart_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return (dma_addr == bad_dma_addr);
}
static int no_agp;
static __init unsigned long check_iommu_size(unsigned long aper, u64 aper_size)
@ -695,7 +678,6 @@ static const struct dma_map_ops gart_dma_ops = {
.unmap_page = gart_unmap_page,
.alloc = gart_alloc_coherent,
.free = gart_free_coherent,
.mapping_error = gart_mapping_error,
.dma_supported = dma_direct_supported,
};
@ -730,7 +712,6 @@ int __init gart_iommu_init(void)
unsigned long aper_base, aper_size;
unsigned long start_pfn, end_pfn;
unsigned long scratch;
long i;
if (!amd_nb_has_feature(AMD_NB_GART))
return 0;
@ -784,19 +765,12 @@ int __init gart_iommu_init(void)
}
#endif
/*
* Out of IOMMU space handling.
* Reserve some invalid pages at the beginning of the GART.
*/
bitmap_set(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
pr_info("PCI-DMA: Reserving %luMB of IOMMU area in the AGP aperture\n",
iommu_size >> 20);
agp_memory_reserved = iommu_size;
iommu_start = aper_size - iommu_size;
iommu_bus_base = info.aper_base + iommu_start;
bad_dma_addr = iommu_bus_base;
iommu_gatt_base = agp_gatt_table + (iommu_start>>PAGE_SHIFT);
/*
@ -838,8 +812,6 @@ int __init gart_iommu_init(void)
if (!scratch)
panic("Cannot allocate iommu scratch page");
gart_unmapped_entry = GPTE_ENCODE(__pa(scratch));
for (i = EMERGENCY_PAGES; i < iommu_pages; i++)
iommu_gatt_base[i] = gart_unmapped_entry;
flush_gart();
dma_ops = &gart_dma_ops;