On 12.06.19 13:12, Halil Pasic wrote:
On s390, protected virtualization guests have to use bounced I/O buffers. That requires some plumbing.
sed 's/ / /'
Let us make sure, any device that uses DMA API with direct ops correctly is spared from the problems, that a hypervisor attempting I/O to a non-shared page would bring.
That sentence reads pretty cumbersome.
Signed-off-by: Halil Pasic <pa...@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbre...@linux.ibm.com> --- arch/s390/Kconfig | 4 +++ arch/s390/include/asm/mem_encrypt.h | 18 +++++++++++ arch/s390/mm/init.c | 47 +++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+) create mode 100644 arch/s390/include/asm/mem_encrypt.h diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 109243fdb6ec..88d8355b7bf7 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -1,4 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 +config ARCH_HAS_MEM_ENCRYPT + def_bool y + config MMU def_bool y@@ -187,6 +190,7 @@ config S390select VIRT_CPU_ACCOUNTING select ARCH_HAS_SCALED_CPUTIME select HAVE_NMI + select SWIOTLBconfig SCHED_OMIT_FRAME_POINTERdiff --git a/arch/s390/include/asm/mem_encrypt.h b/arch/s390/include/asm/mem_encrypt.h new file mode 100644 index 000000000000..0898c09a888c --- /dev/null +++ b/arch/s390/include/asm/mem_encrypt.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef S390_MEM_ENCRYPT_H__ +#define S390_MEM_ENCRYPT_H__ + +#ifndef __ASSEMBLY__ + +#define sme_me_mask 0ULL + +static inline bool sme_active(void) { return false; } +extern bool sev_active(void); + +int set_memory_encrypted(unsigned long addr, int numpages); +int set_memory_decrypted(unsigned long addr, int numpages); + +#endif /* __ASSEMBLY__ */ + +#endif /* S390_MEM_ENCRYPT_H__ */ + diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 14d1eae9fe43..f0bee6af3960 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -18,6 +18,7 @@ #include <linux/mman.h> #include <linux/mm.h> #include <linux/swap.h> +#include <linux/swiotlb.h> #include <linux/smp.h> #include <linux/init.h> #include <linux/pagemap.h> @@ -29,6 +30,7 @@ #include <linux/export.h> #include <linux/cma.h> #include <linux/gfp.h> +#include <linux/dma-mapping.h> #include <asm/processor.h> #include <linux/uaccess.h> #include <asm/pgtable.h> @@ -42,6 +44,8 @@ #include <asm/sclp.h> #include <asm/set_memory.h> #include <asm/kasan.h> +#include <asm/dma-mapping.h> +#include <asm/uv.h>pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); @@ -128,6 +132,47 @@ void mark_rodata_ro(void)pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); }+int set_memory_encrypted(unsigned long addr, int numpages)+{ + int i; + + /* make specified pages unshared, (swiotlb, dma_free) */ + for (i = 0; i < numpages; ++i) { + uv_remove_shared(addr); + addr += PAGE_SIZE; + } + return 0; +} + +int set_memory_decrypted(unsigned long addr, int numpages) +{ + int i; + /* make specified pages shared (swiotlb, dma_alloca) */ + for (i = 0; i < numpages; ++i) { + uv_set_shared(addr); + addr += PAGE_SIZE; + } + return 0; +} + +/* are we a protected virtualization guest? */ +bool sev_active(void) +{ + return is_prot_virt_guest(); +} + +/* protected virtualization */ +static void pv_init(void) +{ + if (!is_prot_virt_guest()) + return; + + /* make sure bounce buffers are shared */ + swiotlb_init(1); + swiotlb_update_mem_attributes(); + swiotlb_force = SWIOTLB_FORCE; +} + void __init mem_init(void) { cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); @@ -136,6 +181,8 @@ void __init mem_init(void) set_max_mapnr(max_low_pfn); high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);+ pv_init();+ /* Setup guest page hinting */ cmma_init();
Reviewed-by: Michael Mueller <m...@linux.ibm.com> Michael _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
