Even when the linear map uses block mappings, regions marked with MEMBLOCK_PTEMAP are mapped at page granularity and can be modified at runtime. Implement the architecture hooks for the lendable-dma-pool to force the last-level mappings, validate ranges and update the direct mapping.
Signed-off-by: Vincent Donnefort vdonnefort@google.com --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/set_memory.h | 2 + arch/arm64/mm/dma-mapping.c | 71 +++++++++++++++++++++++++++++ arch/arm64/mm/pageattr.c | 56 ++++++++++++++++++----- 4 files changed, 118 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1075bc661833..34fe7a7eea82 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -117,6 +117,7 @@ config ARM64 select DYNAMIC_FTRACE if FUNCTION_TRACER select DMA_BOUNCE_UNALIGNED_KMALLOC select DMA_DIRECT_REMAP + select DMA_LENDABLE if DMA_CMA select EDAC_SUPPORT select FRAME_POINTER select FUNCTION_ALIGNMENT_4B diff --git a/arch/arm64/include/asm/set_memory.h b/arch/arm64/include/asm/set_memory.h index b6ec938703d6..ec8bbb59e51f 100644 --- a/arch/arm64/include/asm/set_memory.h +++ b/arch/arm64/include/asm/set_memory.h @@ -17,6 +17,8 @@ int set_memory_valid(unsigned long addr, int numpages, int enable);
int set_direct_map_invalid_noflush(struct page *page, unsigned int numpages); int set_direct_map_default_noflush(struct page *page, unsigned int numpages); +int __set_direct_map_invalid_noflush(struct page *page, unsigned int numpages); +int __set_direct_map_default_noflush(struct page *page, unsigned int numpages); bool kernel_page_present(struct page *page);
int set_memory_encrypted(unsigned long addr, int numpages); diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 7f6f2f40dba2..c324e9826ce2 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -7,9 +7,13 @@ #include <linux/gfp.h> #include <linux/cache.h> #include <linux/dma-map-ops.h> +#include <linux/kernel.h> +#include <linux/memblock.h> #include <xen/xen.h>
#include <asm/cacheflush.h> +#include <asm/set_memory.h> +#include <asm/tlbflush.h> #include <asm/xen/xen-ops.h>
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, @@ -38,6 +42,73 @@ void arch_dma_prep_coherent(struct page *page, size_t size) dcache_clean_poc(start, start + size); }
+#ifdef CONFIG_DMA_LENDABLE +int __init arch_dma_mark_lendable(phys_addr_t base, phys_addr_t size) +{ + if (!PAGE_ALIGNED(base | size)) + return -EINVAL; + + return memblock_mark_ptemap(base, size); +} + +bool __init arch_dma_is_lendable(struct page *page, unsigned int nr_pages) +{ + return direct_map_is_ptemap(page, nr_pages); +} + +int arch_dma_zap_direct_map(struct page *page, unsigned int nr_pages, + bool from_lendable) +{ + unsigned long start = (unsigned long)page_address(page); + unsigned long end = start + ((unsigned long)nr_pages << PAGE_SHIFT); + int ret; + + /* + * arch_dma_prep_coherent() only cleans as normal DMA buffers retain a + * cacheable linear-map alias. Since that alias is being removed here, + * also invalidate to make sure they can't be evicted later on while the + * memory is secured. + */ + dcache_clean_inval_poc(start, end); + + if (from_lendable) { + ret = __set_direct_map_invalid_noflush(page, nr_pages); + } else { + might_sleep(); + ret = set_direct_map_invalid_noflush(page, nr_pages); + } + + if (ret) + return ret; + + flush_tlb_kernel_range(start, end); + + return 0; +} + +int arch_dma_restore_direct_map(struct page *page, unsigned int nr_pages, + bool from_lendable) +{ + unsigned long start = (unsigned long)page_address(page); + unsigned long end = start + ((unsigned long)nr_pages << PAGE_SHIFT); + int ret; + + if (from_lendable) { + ret = __set_direct_map_default_noflush(page, nr_pages); + } else { + might_sleep(); + ret = set_direct_map_default_noflush(page, nr_pages); + } + + if (ret) + return ret; + + dcache_inval_poc(start, end); + + return 0; +} +#endif /* CONFIG_DMA_LENDABLE */ + void arch_setup_dma_ops(struct device *dev, bool coherent) { int cls = cache_line_size_of_cpu(); diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index c7662fd2fcb2..467a420af0f5 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -167,8 +167,8 @@ bool __init direct_map_is_ptemap(struct page *page, unsigned int numpages) NULL, NULL); }
-static int update_range_prot(unsigned long start, unsigned long size, - pgprot_t set_mask, pgprot_t clear_mask) +static int __update_range_prot(unsigned long start, unsigned long size, + pgprot_t set_mask, pgprot_t clear_mask) { struct page_change_data data; int ret; @@ -176,10 +176,6 @@ static int update_range_prot(unsigned long start, unsigned long size, data.set_mask = set_mask; data.clear_mask = clear_mask;
- ret = split_kernel_leaf_mapping(start, start + size); - if (WARN_ON_ONCE(ret)) - return ret; - lazy_mmu_mode_enable();
/* @@ -194,6 +190,18 @@ static int update_range_prot(unsigned long start, unsigned long size, return ret; }
+static int update_range_prot(unsigned long start, unsigned long size, + pgprot_t set_mask, pgprot_t clear_mask) +{ + int ret; + + ret = split_kernel_leaf_mapping(start, start + size); + if (WARN_ON_ONCE(ret)) + return ret; + + return __update_range_prot(start, size, set_mask, clear_mask); +} + static int __change_memory_common(unsigned long start, unsigned long size, pgprot_t set_mask, pgprot_t clear_mask) { @@ -316,28 +324,52 @@ int set_memory_valid(unsigned long addr, int numpages, int enable) __pgprot(PTE_PRESENT_VALID_KERNEL)); }
-int set_direct_map_invalid_noflush(struct page *page, unsigned int numpages) +int __set_direct_map_invalid_noflush(struct page *page, unsigned int numpages) { pgprot_t clear_mask = __pgprot(PTE_PRESENT_VALID_KERNEL); pgprot_t set_mask = __pgprot(PTE_PRESENT_INVALID);
+ return __update_range_prot((unsigned long)page_address(page), + PAGE_SIZE * numpages, set_mask, clear_mask); +} + +int set_direct_map_invalid_noflush(struct page *page, unsigned int numpages) +{ + unsigned long start = (unsigned long)page_address(page); + int ret; + if (!can_set_direct_map()) return 0;
- return update_range_prot((unsigned long)page_address(page), - PAGE_SIZE * numpages, set_mask, clear_mask); + ret = split_kernel_leaf_mapping(start, start + PAGE_SIZE * numpages); + if (WARN_ON_ONCE(ret)) + return ret; + + return __set_direct_map_invalid_noflush(page, numpages); }
-int set_direct_map_default_noflush(struct page *page, unsigned int numpages) +int __set_direct_map_default_noflush(struct page *page, unsigned int numpages) { pgprot_t set_mask = __pgprot(PTE_PRESENT_VALID_KERNEL | PTE_WRITE); pgprot_t clear_mask = __pgprot(PTE_PRESENT_INVALID | PTE_RDONLY);
+ return __update_range_prot((unsigned long)page_address(page), + PAGE_SIZE * numpages, set_mask, clear_mask); +} + +int set_direct_map_default_noflush(struct page *page, unsigned int numpages) +{ + unsigned long start = (unsigned long)page_address(page); + int ret; + if (!can_set_direct_map()) return 0;
- return update_range_prot((unsigned long)page_address(page), - PAGE_SIZE * numpages, set_mask, clear_mask); + ret = split_kernel_leaf_mapping(start, start + PAGE_SIZE * numpages); + if (WARN_ON_ONCE(ret)) + return ret; + + return __set_direct_map_default_noflush(page, numpages); }
int __set_memory_enc_dec(unsigned long addr, int numpages, bool encrypt)