Re: [PATCH 10/15] swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
On Wed, Apr 06, 2022 at 08:25:32PM -0400, Konrad Rzeszutek Wilk wrote: > > diff --git a/arch/powerpc/platforms/pseries/svm.c > > b/arch/powerpc/platforms/pseries/svm.c > > index c5228f4969eb2..3b4045d508ec8 100644 > > --- a/arch/powerpc/platforms/pseries/svm.c > > +++ b/arch/powerpc/platforms/pseries/svm.c > > @@ -28,7 +28,7 @@ static int __init init_svm(void) > > * need to use the SWIOTLB buffer for DMA even if dma_capable() says > > * otherwise. > > */ > > - swiotlb_force = SWIOTLB_FORCE; > > + ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; > > This is the only place you set the ppc_swiotlb_flags.. so I wonder why > the '|=' instead of just '=' ? Preparing for setting others and not clobbering the value.
Re: [PATCH 10/15] swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
> diff --git a/arch/powerpc/platforms/pseries/svm.c > b/arch/powerpc/platforms/pseries/svm.c > index c5228f4969eb2..3b4045d508ec8 100644 > --- a/arch/powerpc/platforms/pseries/svm.c > +++ b/arch/powerpc/platforms/pseries/svm.c > @@ -28,7 +28,7 @@ static int __init init_svm(void) >* need to use the SWIOTLB buffer for DMA even if dma_capable() says >* otherwise. >*/ > - swiotlb_force = SWIOTLB_FORCE; > + ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; This is the only place you set the ppc_swiotlb_flags.. so I wonder why the '|=' instead of just '=' ? Either way: Reviewed-by: Konrad Rzeszutek Wilk Thank you!
[PATCH 10/15] swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
Power SVM wants to allocate a swiotlb buffer that is not restricted to low memory for the trusted hypervisor scheme. Consolidate the support for this into the swiotlb_init interface by adding a new flag. Signed-off-by: Christoph Hellwig --- arch/powerpc/include/asm/svm.h | 4 arch/powerpc/include/asm/swiotlb.h | 1 + arch/powerpc/kernel/dma-swiotlb.c| 1 + arch/powerpc/mm/mem.c| 5 + arch/powerpc/platforms/pseries/svm.c | 26 +- include/linux/swiotlb.h | 1 + kernel/dma/swiotlb.c | 11 +-- 7 files changed, 14 insertions(+), 35 deletions(-) diff --git a/arch/powerpc/include/asm/svm.h b/arch/powerpc/include/asm/svm.h index 7546402d796af..85580b30aba48 100644 --- a/arch/powerpc/include/asm/svm.h +++ b/arch/powerpc/include/asm/svm.h @@ -15,8 +15,6 @@ static inline bool is_secure_guest(void) return mfmsr() & MSR_S; } -void __init svm_swiotlb_init(void); - void dtl_cache_ctor(void *addr); #define get_dtl_cache_ctor() (is_secure_guest() ? dtl_cache_ctor : NULL) @@ -27,8 +25,6 @@ static inline bool is_secure_guest(void) return false; } -static inline void svm_swiotlb_init(void) {} - #define get_dtl_cache_ctor() NULL #endif /* CONFIG_PPC_SVM */ diff --git a/arch/powerpc/include/asm/swiotlb.h b/arch/powerpc/include/asm/swiotlb.h index 3c1a1cd161286..4203b5e0a88ed 100644 --- a/arch/powerpc/include/asm/swiotlb.h +++ b/arch/powerpc/include/asm/swiotlb.h @@ -9,6 +9,7 @@ #include extern unsigned int ppc_swiotlb_enable; +extern unsigned int ppc_swiotlb_flags; #ifdef CONFIG_SWIOTLB void swiotlb_detect_4g(void); diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c index fc7816126a401..ba256c37bcc0f 100644 --- a/arch/powerpc/kernel/dma-swiotlb.c +++ b/arch/powerpc/kernel/dma-swiotlb.c @@ -10,6 +10,7 @@ #include unsigned int ppc_swiotlb_enable; +unsigned int ppc_swiotlb_flags; void __init swiotlb_detect_4g(void) { diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index e1519e2edc656..a4d65418c30a9 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -249,10 +249,7 @@ void __init mem_init(void) * back to to-down. */ memblock_set_bottom_up(true); - if (is_secure_guest()) - svm_swiotlb_init(); - else - swiotlb_init(ppc_swiotlb_enable, 0); + swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); #endif high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c index c5228f4969eb2..3b4045d508ec8 100644 --- a/arch/powerpc/platforms/pseries/svm.c +++ b/arch/powerpc/platforms/pseries/svm.c @@ -28,7 +28,7 @@ static int __init init_svm(void) * need to use the SWIOTLB buffer for DMA even if dma_capable() says * otherwise. */ - swiotlb_force = SWIOTLB_FORCE; + ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; /* Share the SWIOTLB buffer with the host. */ swiotlb_update_mem_attributes(); @@ -37,30 +37,6 @@ static int __init init_svm(void) } machine_early_initcall(pseries, init_svm); -/* - * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it - * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have - * any addressing limitation, we don't need to allocate it in low addresses. - */ -void __init svm_swiotlb_init(void) -{ - unsigned char *vstart; - unsigned long bytes, io_tlb_nslabs; - - io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT); - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); - - bytes = io_tlb_nslabs << IO_TLB_SHIFT; - - vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE); - if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false)) - return; - - - memblock_free(vstart, PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); - panic("SVM: Cannot allocate SWIOTLB buffer"); -} - int set_memory_encrypted(unsigned long addr, int numpages) { if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index ae0407173e845..eabdd89987027 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -15,6 +15,7 @@ struct scatterlist; #define SWIOTLB_VERBOSE(1 << 0) /* verbose initialization */ #define SWIOTLB_FORCE (1 << 1) /* force bounce buffering */ +#define SWIOTLB_ANY(1 << 2) /* allow any memory for the buffer */ /* * Maximum allowable number of contiguous slabs to map, diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 86e877a96b828..f6e091424af3d 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -266,8 +266,15 @@ void __init swiotlb_init(bool addressing_limit, unsigned int flags) if (swiotlb_force_disable) return; - /* Get IO TLB
[PATCH 10/15] swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
Power SVM wants to allocate a swiotlb buffer that is not restricted to low memory for the trusted hypervisor scheme. Consolidate the support for this into the swiotlb_init interface by adding a new flag. Signed-off-by: Christoph Hellwig --- arch/powerpc/include/asm/svm.h | 4 arch/powerpc/include/asm/swiotlb.h | 1 + arch/powerpc/kernel/dma-swiotlb.c| 1 + arch/powerpc/mm/mem.c| 5 + arch/powerpc/platforms/pseries/svm.c | 26 +- include/linux/swiotlb.h | 1 + kernel/dma/swiotlb.c | 11 +-- 7 files changed, 14 insertions(+), 35 deletions(-) diff --git a/arch/powerpc/include/asm/svm.h b/arch/powerpc/include/asm/svm.h index 7546402d796af..85580b30aba48 100644 --- a/arch/powerpc/include/asm/svm.h +++ b/arch/powerpc/include/asm/svm.h @@ -15,8 +15,6 @@ static inline bool is_secure_guest(void) return mfmsr() & MSR_S; } -void __init svm_swiotlb_init(void); - void dtl_cache_ctor(void *addr); #define get_dtl_cache_ctor() (is_secure_guest() ? dtl_cache_ctor : NULL) @@ -27,8 +25,6 @@ static inline bool is_secure_guest(void) return false; } -static inline void svm_swiotlb_init(void) {} - #define get_dtl_cache_ctor() NULL #endif /* CONFIG_PPC_SVM */ diff --git a/arch/powerpc/include/asm/swiotlb.h b/arch/powerpc/include/asm/swiotlb.h index 3c1a1cd161286..4203b5e0a88ed 100644 --- a/arch/powerpc/include/asm/swiotlb.h +++ b/arch/powerpc/include/asm/swiotlb.h @@ -9,6 +9,7 @@ #include extern unsigned int ppc_swiotlb_enable; +extern unsigned int ppc_swiotlb_flags; #ifdef CONFIG_SWIOTLB void swiotlb_detect_4g(void); diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c index fc7816126a401..ba256c37bcc0f 100644 --- a/arch/powerpc/kernel/dma-swiotlb.c +++ b/arch/powerpc/kernel/dma-swiotlb.c @@ -10,6 +10,7 @@ #include unsigned int ppc_swiotlb_enable; +unsigned int ppc_swiotlb_flags; void __init swiotlb_detect_4g(void) { diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index e1519e2edc656..a4d65418c30a9 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -249,10 +249,7 @@ void __init mem_init(void) * back to to-down. */ memblock_set_bottom_up(true); - if (is_secure_guest()) - svm_swiotlb_init(); - else - swiotlb_init(ppc_swiotlb_enable, 0); + swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags); #endif high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c index c5228f4969eb2..3b4045d508ec8 100644 --- a/arch/powerpc/platforms/pseries/svm.c +++ b/arch/powerpc/platforms/pseries/svm.c @@ -28,7 +28,7 @@ static int __init init_svm(void) * need to use the SWIOTLB buffer for DMA even if dma_capable() says * otherwise. */ - swiotlb_force = SWIOTLB_FORCE; + ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; /* Share the SWIOTLB buffer with the host. */ swiotlb_update_mem_attributes(); @@ -37,30 +37,6 @@ static int __init init_svm(void) } machine_early_initcall(pseries, init_svm); -/* - * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it - * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have - * any addressing limitation, we don't need to allocate it in low addresses. - */ -void __init svm_swiotlb_init(void) -{ - unsigned char *vstart; - unsigned long bytes, io_tlb_nslabs; - - io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT); - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); - - bytes = io_tlb_nslabs << IO_TLB_SHIFT; - - vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE); - if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false)) - return; - - - memblock_free(vstart, PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); - panic("SVM: Cannot allocate SWIOTLB buffer"); -} - int set_memory_encrypted(unsigned long addr, int numpages) { if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index ae0407173e845..eabdd89987027 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -15,6 +15,7 @@ struct scatterlist; #define SWIOTLB_VERBOSE(1 << 0) /* verbose initialization */ #define SWIOTLB_FORCE (1 << 1) /* force bounce buffering */ +#define SWIOTLB_ANY(1 << 2) /* allow any memory for the buffer */ /* * Maximum allowable number of contiguous slabs to map, diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 5ac6e128d4279..2ad12562c94fe 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -266,8 +266,15 @@ void __init swiotlb_init(bool addressing_limit, unsigned int flags) if (swiotlb_force_disable) return; - /* Get IO TLB