From: Juergen Gross Date: Wed, 22 Jun 2022 06:38:36 +0000 (+0200) Subject: virtio: replace restricted mem access flag with callback X-Git-Tag: v6.1-rc5~412^2~18 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a603002eea8213eec5211be5a85db8340aea06d0;p=platform%2Fkernel%2Flinux-starfive.git virtio: replace restricted mem access flag with callback Instead of having a global flag to require restricted memory access for all virtio devices, introduce a callback which can select that requirement on a per-device basis. For convenience add a common function returning always true, which can be used for use cases like SEV. Per default use a callback always returning false. As the callback needs to be set in early init code already, add a virtio anchor which is builtin in case virtio is enabled. Signed-off-by: Juergen Gross Tested-by: Oleksandr Tyshchenko # Arm64 guest using Xen Reviewed-by: Stefano Stabellini Link: https://lore.kernel.org/r/20220622063838.8854-2-jgross@suse.com Signed-off-by: Juergen Gross --- diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 6a0ac00..4a154a0 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -31,7 +31,6 @@ #include #include #include -#include #include #include #include @@ -48,6 +47,7 @@ #include #include #include +#include #include pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir"); @@ -175,7 +175,7 @@ static void pv_init(void) if (!is_prot_virt_guest()) return; - platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); + virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); /* make sure bounce buffers are shared */ swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c index f6d038e..9745268 100644 --- a/arch/x86/mm/mem_encrypt_amd.c +++ b/arch/x86/mm/mem_encrypt_amd.c @@ -20,8 +20,8 @@ #include #include #include +#include #include -#include #include #include @@ -245,7 +245,7 @@ void __init sev_setup_arch(void) swiotlb_adjust_size(size); /* Set restricted memory access for virtio. */ - platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); + virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); } 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 e1556d2..56c77f63 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -1,6 +1,10 @@ # SPDX-License-Identifier: GPL-2.0-only +config VIRTIO_ANCHOR + bool + config VIRTIO tristate + select VIRTIO_ANCHOR help This option is selected by any driver which implements the virtio bus, such as CONFIG_VIRTIO_PCI, CONFIG_VIRTIO_MMIO, CONFIG_RPMSG diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 0a82d08..8e98d24 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o +obj-$(CONFIG_VIRTIO_ANCHOR) += virtio_anchor.o obj-$(CONFIG_VIRTIO_PCI_LIB) += virtio_pci_modern_dev.o obj-$(CONFIG_VIRTIO_PCI_LIB_LEGACY) += virtio_pci_legacy_dev.o obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 7deeed3..14c142d 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -2,10 +2,10 @@ #include #include #include +#include #include #include #include -#include #include /* Unique numbering for virtio devices. */ @@ -174,7 +174,7 @@ static int virtio_features_ok(struct virtio_device *dev) might_sleep(); - if (platform_has(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS)) { + if (virtio_check_mem_acc_cb(dev)) { if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { dev_warn(&dev->dev, "device must provide VIRTIO_F_VERSION_1\n"); diff --git a/drivers/virtio/virtio_anchor.c b/drivers/virtio/virtio_anchor.c new file mode 100644 index 0000000..4d6a5d2 --- /dev/null +++ b/drivers/virtio/virtio_anchor.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include + +bool virtio_require_restricted_mem_acc(struct virtio_device *dev) +{ + return true; +} +EXPORT_SYMBOL_GPL(virtio_require_restricted_mem_acc); + +static bool virtio_no_restricted_mem_acc(struct virtio_device *dev) +{ + return false; +} + +bool (*virtio_check_mem_acc_cb)(struct virtio_device *dev) = + virtio_no_restricted_mem_acc; +EXPORT_SYMBOL_GPL(virtio_check_mem_acc_cb); diff --git a/include/linux/platform-feature.h b/include/linux/platform-feature.h index b2f48be..6ed8599 100644 --- a/include/linux/platform-feature.h +++ b/include/linux/platform-feature.h @@ -6,11 +6,7 @@ #include /* The platform features are starting with the architecture specific ones. */ - -/* 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) +#define PLATFORM_FEAT_N (0 + PLATFORM_ARCH_FEAT_N) void platform_set(unsigned int feature); void platform_clear(unsigned int feature); diff --git a/include/linux/virtio_anchor.h b/include/linux/virtio_anchor.h new file mode 100644 index 0000000..432e6c0 --- /dev/null +++ b/include/linux/virtio_anchor.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_VIRTIO_ANCHOR_H +#define _LINUX_VIRTIO_ANCHOR_H + +#ifdef CONFIG_VIRTIO_ANCHOR +struct virtio_device; + +bool virtio_require_restricted_mem_acc(struct virtio_device *dev); +extern bool (*virtio_check_mem_acc_cb)(struct virtio_device *dev); + +static inline void virtio_set_mem_acc_cb(bool (*func)(struct virtio_device *)) +{ + virtio_check_mem_acc_cb = func; +} +#else +#define virtio_set_mem_acc_cb(func) do { } while (0) +#endif + +#endif /* _LINUX_VIRTIO_ANCHOR_H */ diff --git a/include/xen/xen.h b/include/xen/xen.h index 0780a81..ac5a144 100644 --- a/include/xen/xen.h +++ b/include/xen/xen.h @@ -52,12 +52,12 @@ bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, extern u64 xen_saved_max_mem_size; #endif -#include +#include static inline void xen_set_restricted_virtio_memory_access(void) { if (IS_ENABLED(CONFIG_XEN_VIRTIO) && xen_domain()) - platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); + virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); } #ifdef CONFIG_XEN_UNPOPULATED_ALLOC