On 04.05.22 17:57, Juergen Gross wrote:
Instead of using arch_has_restricted_virtio_memory_access() together with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those with platform_has() and a new platform feature PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS. Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Could I get some feedback from the s390 side, please? Juergen
--- V2: - move setting of PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS in SEV case to sev_setup_arch(). V3: - remove Hyper-V chunk (Michael Kelley) - remove include virtio_config.h from mem_encrypt.c (Oleksandr Tyshchenko) - add comment for PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS (Oleksandr Tyshchenko) --- arch/s390/Kconfig | 1 - arch/s390/mm/init.c | 13 +++---------- arch/x86/Kconfig | 1 - arch/x86/mm/mem_encrypt.c | 7 ------- arch/x86/mm/mem_encrypt_amd.c | 4 ++++ drivers/virtio/Kconfig | 6 ------ drivers/virtio/virtio.c | 5 ++--- include/linux/platform-feature.h | 6 +++++- include/linux/virtio_config.h | 9 --------- 9 files changed, 14 insertions(+), 38 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index e084c72104f8..f97a22ae69a8 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -772,7 +772,6 @@ menu "Virtualization" config PROTECTED_VIRTUALIZATION_GUEST def_bool n prompt "Protected virtualization guest support" - select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS help Select this option, if you want to be able to run this kernel as a protected virtualization KVM guest. diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 86ffd0d51fd5..2c3b451813ed 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -31,6 +31,7 @@ #include <linux/cma.h> #include <linux/gfp.h> #include <linux/dma-direct.h> +#include <linux/platform-feature.h> #include <asm/processor.h> #include <linux/uaccess.h> #include <asm/pgalloc.h> @@ -168,22 +169,14 @@ bool force_dma_unencrypted(struct device *dev) return is_prot_virt_guest(); }-#ifdef CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS- -int arch_has_restricted_virtio_memory_access(void) -{ - return is_prot_virt_guest(); -} -EXPORT_SYMBOL(arch_has_restricted_virtio_memory_access); - -#endif - /* protected virtualization */ static void pv_init(void) { if (!is_prot_virt_guest()) return;+ platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS);+ /* make sure bounce buffers are shared */ swiotlb_force = SWIOTLB_FORCE; swiotlb_init(1); diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 4bed3abf444d..eeb7c6c8eec5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1515,7 +1515,6 @@ config X86_CPA_STATISTICS config X86_MEM_ENCRYPT select ARCH_HAS_FORCE_DMA_UNENCRYPTED select DYNAMIC_PHYSICAL_MASK - select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS def_bool nconfig AMD_MEM_ENCRYPTdiff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 50d209939c66..18a55a0f1ca2 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -12,7 +12,6 @@ #include <linux/swiotlb.h> #include <linux/cc_platform.h> #include <linux/mem_encrypt.h> -#include <linux/virtio_config.h>/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */bool force_dma_unencrypted(struct device *dev) @@ -76,9 +75,3 @@ void __init mem_encrypt_init(void)print_mem_encrypt_feature_info();} - -int arch_has_restricted_virtio_memory_access(void) -{ - return cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT); -} -EXPORT_SYMBOL_GPL(arch_has_restricted_virtio_memory_access); diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c index 6169053c2854..39b71084d36b 100644 --- a/arch/x86/mm/mem_encrypt_amd.c +++ b/arch/x86/mm/mem_encrypt_amd.c @@ -21,6 +21,7 @@ #include <linux/dma-mapping.h> #include <linux/virtio_config.h> #include <linux/cc_platform.h> +#include <linux/platform-feature.h>#include <asm/tlbflush.h>#include <asm/fixmap.h> @@ -206,6 +207,9 @@ void __init sev_setup_arch(void) size = total_mem * 6 / 100; size = clamp_val(size, IO_TLB_DEFAULT_SIZE, SZ_1G); swiotlb_adjust_size(size); + + /* Set restricted memory access for virtio. */ + platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); }static unsigned long pg_level_to_pfn(int level, pte_t *kpte, pgprot_t *ret_prot)diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index b5adf6abd241..a6dc8b5846fe 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -6,12 +6,6 @@ config VIRTIO bus, such as CONFIG_VIRTIO_PCI, CONFIG_VIRTIO_MMIO, CONFIG_RPMSG or CONFIG_S390_GUEST.-config ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS- bool - help - This option is selected if the architecture may need to enforce - VIRTIO_F_ACCESS_PLATFORM - config VIRTIO_PCI_LIB tristate help diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 22f15f444f75..371e16b18381 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -5,6 +5,7 @@ #include <linux/module.h> #include <linux/idr.h> #include <linux/of.h> +#include <linux/platform-feature.h> #include <uapi/linux/virtio_ids.h>/* Unique numbering for virtio devices. */@@ -170,12 +171,10 @@ EXPORT_SYMBOL_GPL(virtio_add_status); static int virtio_features_ok(struct virtio_device *dev) { unsigned status; - int ret;might_sleep(); - ret = arch_has_restricted_virtio_memory_access();- if (ret) { + if (platform_has(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS)) { if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { dev_warn(&dev->dev, "device must provide VIRTIO_F_VERSION_1\n"); diff --git a/include/linux/platform-feature.h b/include/linux/platform-feature.h index 6ed859928b97..b2f48be999fa 100644 --- a/include/linux/platform-feature.h +++ b/include/linux/platform-feature.h @@ -6,7 +6,11 @@ #include <asm/platform-feature.h>/* The platform features are starting with the architecture specific ones. */-#define PLATFORM_FEAT_N (0 + PLATFORM_ARCH_FEAT_N) + +/* Used to enable platform specific DMA handling for virtio devices. */ +#define PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS (0 + PLATFORM_ARCH_FEAT_N) + +#define PLATFORM_FEAT_N (1 + PLATFORM_ARCH_FEAT_N)void platform_set(unsigned int feature);void platform_clear(unsigned int feature); diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index b341dd62aa4d..79498298519d 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -559,13 +559,4 @@ static inline void virtio_cwrite64(struct virtio_device *vdev, _r; \ })-#ifdef CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS-int arch_has_restricted_virtio_memory_access(void); -#else -static inline int arch_has_restricted_virtio_memory_access(void) -{ - return 0; -} -#endif /* CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS */ - #endif /* _LINUX_VIRTIO_CONFIG_H */
Attachment:
OpenPGP_0xB0DE9DD628BF132F.asc
Description: OpenPGP public key
Attachment:
OpenPGP_signature
Description: OpenPGP digital signature
