[PATCH 08/11] swiotlb: make the swiotlb_init interface more useful
From: Christoph Hellwig <hch@lst.de>
Date: 2022-02-22 15:42:23
Also in:
linux-arm-kernel, linux-hyperv, linux-iommu, linux-mips, linux-pci, linux-riscv, linux-s390, xen-devel
Subsystem:
arm port, arm64 port (aarch64 architecture), dma mapping helpers, hyper-v/azure core and drivers, linux for powerpc (32-bit and 64-bit), mips, mips/loongson64 architecture, risc-v architecture, s390 architecture, the rest, tracing, x86 architecture (32-bit and 64-bit), x86 mm, xen hypervisor interface, xen swiotlb subsystem · Maintainers:
Russell King, Catalin Marinas, Will Deacon, Marek Szyprowski, "K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Madhavan Srinivasan, Michael Ellerman, Thomas Bogendoerfer, Huacai Chen, Jiaxun Yang, Paul Walmsley, Palmer Dabbelt, Albert Ou, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds, Steven Rostedt, Masami Hiramatsu, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra, Juergen Gross, Stefano Stabellini
Pass a bool to pass if swiotlb needs to be enabled based on the addressing needs and replace the verbose argument with a set of flags, including one to force enable bounce buffering. Note that this patch removes the possibility to force xen-swiotlb use using swiotlb=force on the command line on x86 (arm and arm64 never supported that), but this interface will be restored shortly. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/arm/mm/init.c | 6 +---- arch/arm64/mm/init.c | 6 +---- arch/ia64/mm/init.c | 4 +-- arch/mips/cavium-octeon/dma-octeon.c | 2 +- arch/mips/loongson64/dma.c | 2 +- arch/mips/sibyte/common/dma.c | 2 +- arch/powerpc/include/asm/swiotlb.h | 1 + arch/powerpc/mm/mem.c | 3 ++- arch/powerpc/platforms/pseries/setup.c | 3 --- arch/riscv/mm/init.c | 8 +----- arch/s390/mm/init.c | 3 +-- arch/x86/kernel/cpu/mshyperv.c | 8 ------ arch/x86/kernel/pci-dma.c | 17 ++++++------- arch/x86/mm/mem_encrypt_amd.c | 3 --- drivers/xen/swiotlb-xen.c | 4 +-- include/linux/swiotlb.h | 15 ++++++----- include/trace/events/swiotlb.h | 29 ++++++++------------- kernel/dma/swiotlb.c | 35 ++++++++++++++------------ 18 files changed, 57 insertions(+), 94 deletions(-)
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 6d0cb0f7bc54b..73f30d278b565 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c@@ -312,11 +312,7 @@ static void __init free_highpages(void) void __init mem_init(void) { #ifdef CONFIG_ARM_LPAE - if (swiotlb_force == SWIOTLB_FORCE || - max_pfn > arm_dma_pfn_limit) - swiotlb_init(1); - else - swiotlb_force = SWIOTLB_NO_FORCE; + swiotlb_init(max_pfn > arm_dma_pfn_limit, SWIOTLB_VERBOSE); #endif set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index db63cc885771a..52102adda3d28 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c@@ -373,11 +373,7 @@ void __init bootmem_init(void) */ void __init mem_init(void) { - if (swiotlb_force == SWIOTLB_FORCE || - max_pfn > PFN_DOWN(arm64_dma_phys_limit)) - swiotlb_init(1); - else if (!xen_swiotlb_detect()) - swiotlb_force = SWIOTLB_NO_FORCE; + swiotlb_init(max_pfn > PFN_DOWN(arm64_dma_phys_limit), SWIOTLB_VERBOSE); /* this will put all unused low memory onto the freelists */ memblock_free_all();
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 5d165607bf354..3c3e15b22608f 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c@@ -437,9 +437,7 @@ mem_init (void) if (iommu_detected) break; #endif -#ifdef CONFIG_SWIOTLB - swiotlb_init(1); -#endif + swiotlb_init(true, SWIOTLB_VERBOSE); } while (0); #ifdef CONFIG_FLATMEM
diff --git a/arch/mips/cavium-octeon/dma-octeon.c b/arch/mips/cavium-octeon/dma-octeon.c
index fb7547e217263..9fbba6a8fa4c5 100644
--- a/arch/mips/cavium-octeon/dma-octeon.c
+++ b/arch/mips/cavium-octeon/dma-octeon.c@@ -235,5 +235,5 @@ void __init plat_swiotlb_setup(void) #endif swiotlb_adjust_size(swiotlbsize); - swiotlb_init(1); + swiotlb_init(true, SWIOTLB_VERBOSE); }
diff --git a/arch/mips/loongson64/dma.c b/arch/mips/loongson64/dma.c
index 364f2f27c8723..8220a1bc0db64 100644
--- a/arch/mips/loongson64/dma.c
+++ b/arch/mips/loongson64/dma.c@@ -24,5 +24,5 @@ phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) void __init plat_swiotlb_setup(void) { - swiotlb_init(1); + swiotlb_init(true, SWIOTLB_VERBOSE); }
diff --git a/arch/mips/sibyte/common/dma.c b/arch/mips/sibyte/common/dma.c
index eb47a94f3583e..c5c2c782aff68 100644
--- a/arch/mips/sibyte/common/dma.c
+++ b/arch/mips/sibyte/common/dma.c@@ -10,5 +10,5 @@ void __init plat_swiotlb_setup(void) { - swiotlb_init(1); + swiotlb_init(true, SWIOTLB_VERBOSE); }
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 <linux/swiotlb.h> 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/mm/mem.c b/arch/powerpc/mm/mem.c
index 8e301cd8925b2..d99b8b5b40ca6 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c@@ -17,6 +17,7 @@ #include <linux/suspend.h> #include <linux/dma-direct.h> +#include <asm/swiotlb.h> #include <asm/machdep.h> #include <asm/rtas.h> #include <asm/kasan.h>
@@ -251,7 +252,7 @@ void __init mem_init(void) if (is_secure_guest()) svm_swiotlb_init(); else - swiotlb_init(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/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 83a04d967a59f..45d637ab58261 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c@@ -838,9 +838,6 @@ static void __init pSeries_setup_arch(void) } ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare; - - if (swiotlb_force == SWIOTLB_FORCE) - ppc_swiotlb_enable = 1; } static void pseries_panic(char *str)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c27294128e182..6cdbb62672fe5 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c@@ -118,13 +118,7 @@ void __init mem_init(void) BUG_ON(!mem_map); #endif /* CONFIG_FLATMEM */ -#ifdef CONFIG_SWIOTLB - if (swiotlb_force == SWIOTLB_FORCE || - max_pfn > PFN_DOWN(dma32_phys_limit)) - swiotlb_init(1); - else - swiotlb_force = SWIOTLB_NO_FORCE; -#endif + swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE); high_memory = (void *)(__va(PFN_PHYS(max_low_pfn))); memblock_free_all();
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 86ffd0d51fd59..6fb6bf64326f9 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c@@ -185,8 +185,7 @@ static void pv_init(void) return; /* make sure bounce buffers are shared */ - swiotlb_force = SWIOTLB_FORCE; - swiotlb_init(1); + swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); swiotlb_update_mem_attributes(); }
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 5a99f993e6392..568274917f1cd 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c@@ -336,14 +336,6 @@ static void __init ms_hyperv_init_platform(void) swiotlb_unencrypted_base = ms_hyperv.shared_gpa_boundary; #endif } - -#ifdef CONFIG_SWIOTLB - /* - * Enable swiotlb force mode in Isolation VM to - * use swiotlb bounce buffer for dma transaction. - */ - swiotlb_force = SWIOTLB_FORCE; -#endif } if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) {
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 32c9cd9d7c257..9576a02a2590f 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c@@ -39,6 +39,7 @@ int iommu_detected __read_mostly = 0; #ifdef CONFIG_SWIOTLB bool x86_swiotlb_enable; +static unsigned int x86_swiotlb_flags; static bool xen_swiotlb; /*
@@ -49,8 +50,7 @@ static void __init pci_swiotlb_detect_4gb(void) { #ifdef CONFIG_SWIOTLB_XEN if (xen_pv_domain()) { - if (xen_initial_domain() || x86_swiotlb_enable || - swiotlb_force == SWIOTLB_FORCE) { + if (xen_initial_domain() || x86_swiotlb_enable) { xen_swiotlb = true; xen_swiotlb_init_early(); dma_ops = &xen_swiotlb_dma_ops;
@@ -73,11 +73,10 @@ static void __init pci_swiotlb_detect_4gb(void) * Set swiotlb to 1 so that bounce buffers are allocated and used for * devices that can't support DMA to encrypted memory. */ - if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) - x86_swiotlb_enable = true; - - if (swiotlb_force == SWIOTLB_FORCE) + if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) { x86_swiotlb_enable = true; + x86_swiotlb_flags |= SWIOTLB_FORCE; + } } #else static inline void __init pci_swiotlb_detect_4gb(void)
@@ -91,9 +90,9 @@ void __init pci_iommu_alloc(void) gart_iommu_hole_init(); amd_iommu_detect(); detect_intel_iommu(); - - if (x86_swiotlb_enable) - swiotlb_init(0); +#ifdef CONFIG_SWIOTLB + swiotlb_init(x86_swiotlb_enable, x86_swiotlb_flags); +#endif } /*
diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c
index 2b2d018ea3450..a72942d569cf9 100644
--- a/arch/x86/mm/mem_encrypt_amd.c
+++ b/arch/x86/mm/mem_encrypt_amd.c@@ -191,9 +191,6 @@ void __init sme_early_init(void) /* Update the protection map with memory encryption mask */ for (i = 0; i < ARRAY_SIZE(protection_map); i++) protection_map[i] = pgprot_encrypted(protection_map[i]); - - if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) - swiotlb_force = SWIOTLB_FORCE; } void __init sev_setup_arch(void)
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 485cd06ed39e7..c2da3eb4826e8 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c@@ -251,7 +251,7 @@ void __init xen_swiotlb_init_early(void) panic("%s (rc:%d)", xen_swiotlb_error(XEN_SWIOTLB_EFIXUP), rc); } - if (swiotlb_init_with_tbl(start, nslabs, true)) + if (swiotlb_init_with_tbl(start, nslabs, SWIOTLB_VERBOSE)) panic("Cannot allocate SWIOTLB buffer"); } #endif /* CONFIG_X86 */
@@ -376,7 +376,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, /* * Oh well, have to allocate and map a bounce buffer. */ - trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); + trace_swiotlb_bounced(dev, dev_addr, size); map = swiotlb_tbl_map_single(dev, phys, size, size, 0, dir, attrs); if (map == (phys_addr_t)DMA_MAPPING_ERROR)
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 1befd6b2ccf5e..dcecf953f7997 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h@@ -13,11 +13,8 @@ struct device; struct page; struct scatterlist; -enum swiotlb_force { - SWIOTLB_NORMAL, /* Default - depending on HW DMA mask etc. */ - SWIOTLB_FORCE, /* swiotlb=force */ - SWIOTLB_NO_FORCE, /* swiotlb=noforce */ -}; +#define SWIOTLB_VERBOSE (1 << 0) /* verbose initialization */ +#define SWIOTLB_FORCE (1 << 1) /* force bounce buffering */ /* * Maximum allowable number of contiguous slabs to map,
@@ -36,8 +33,7 @@ enum swiotlb_force { /* default to 64MB */ #define IO_TLB_DEFAULT_SIZE (64UL<<20) -extern void swiotlb_init(int verbose); -int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose); +int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, unsigned int flags); unsigned long swiotlb_size_or_default(void); extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs); int swiotlb_init_late(size_t size, gfp_t gfp_mask);
@@ -126,13 +122,16 @@ static inline bool is_swiotlb_force_bounce(struct device *dev) return mem && mem->force_bounce; } +void swiotlb_init(bool addressing_limited, unsigned int flags); void __init swiotlb_exit(void); unsigned int swiotlb_max_segment(void); size_t swiotlb_max_mapping_size(struct device *dev); bool is_swiotlb_active(struct device *dev); void __init swiotlb_adjust_size(unsigned long size); #else -#define swiotlb_force SWIOTLB_NO_FORCE +static inline void swiotlb_init(bool addressing_limited, unsigned int flags) +{ +} static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) { return false;
diff --git a/include/trace/events/swiotlb.h b/include/trace/events/swiotlb.h
index 705be43b71ab0..da05c9ebd224a 100644
--- a/include/trace/events/swiotlb.h
+++ b/include/trace/events/swiotlb.h@@ -8,20 +8,15 @@ #include <linux/tracepoint.h> TRACE_EVENT(swiotlb_bounced, - - TP_PROTO(struct device *dev, - dma_addr_t dev_addr, - size_t size, - enum swiotlb_force swiotlb_force), - - TP_ARGS(dev, dev_addr, size, swiotlb_force), + TP_PROTO(struct device *dev, dma_addr_t dev_addr, size_t size), + TP_ARGS(dev, dev_addr, size), TP_STRUCT__entry( - __string( dev_name, dev_name(dev) ) - __field( u64, dma_mask ) - __field( dma_addr_t, dev_addr ) - __field( size_t, size ) - __field( enum swiotlb_force, swiotlb_force ) + __string(dev_name, dev_name(dev)) + __field(u64, dma_mask) + __field(dma_addr_t, dev_addr) + __field(size_t, size) + __field(bool, force) ), TP_fast_assign(
@@ -29,19 +24,15 @@ TRACE_EVENT(swiotlb_bounced, __entry->dma_mask = (dev->dma_mask ? *dev->dma_mask : 0); __entry->dev_addr = dev_addr; __entry->size = size; - __entry->swiotlb_force = swiotlb_force; + __entry->force = is_swiotlb_force_bounce(dev); ), - TP_printk("dev_name: %s dma_mask=%llx dev_addr=%llx " - "size=%zu %s", + TP_printk("dev_name: %s dma_mask=%llx dev_addr=%llx size=%zu %s", __get_str(dev_name), __entry->dma_mask, (unsigned long long)__entry->dev_addr, __entry->size, - __print_symbolic(__entry->swiotlb_force, - { SWIOTLB_NORMAL, "NORMAL" }, - { SWIOTLB_FORCE, "FORCE" }, - { SWIOTLB_NO_FORCE, "NO_FORCE" })) + __entry->force ? "FORCE" : "NORMAL") ); #endif /* _TRACE_SWIOTLB_H */
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index a653fcf1fe6c2..ad604e5a0983d 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c@@ -69,7 +69,8 @@ #define INVALID_PHYS_ADDR (~(phys_addr_t)0) -enum swiotlb_force swiotlb_force; +static bool swiotlb_force_bounce; +static bool swiotlb_force_disable; struct io_tlb_mem io_tlb_default_mem;
@@ -88,9 +89,9 @@ setup_io_tlb_npages(char *str) if (*str == ',') ++str; if (!strcmp(str, "force")) - swiotlb_force = SWIOTLB_FORCE; + swiotlb_force_bounce = true; else if (!strcmp(str, "noforce")) - swiotlb_force = SWIOTLB_NO_FORCE; + swiotlb_force_disable = true; return 0; }
@@ -211,7 +212,7 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, mem->index = 0; mem->late_alloc = late_alloc; - if (swiotlb_force == SWIOTLB_FORCE) + if (swiotlb_force_bounce) mem->force_bounce = true; spin_lock_init(&mem->lock);
@@ -233,12 +234,13 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start, return; } -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, + unsigned int flags) { struct io_tlb_mem *mem = &io_tlb_default_mem; size_t alloc_size; - if (swiotlb_force == SWIOTLB_NO_FORCE) + if (swiotlb_force_disable) return 0; /* protect against double initialization */
@@ -252,8 +254,9 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) __func__, alloc_size, PAGE_SIZE); swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false); + mem->force_bounce = flags & SWIOTLB_FORCE; - if (verbose) + if (flags & SWIOTLB_VERBOSE) swiotlb_print_info(); return 0; }
@@ -262,20 +265,21 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) * Statically reserve bounce buffer space and initialize bounce buffer data * structures for the software IO TLB used to implement the DMA API. */ -void __init -swiotlb_init(int verbose) +void __init swiotlb_init(bool addressing_limit, unsigned int flags) { size_t bytes = PAGE_ALIGN(default_nslabs << IO_TLB_SHIFT); void *tlb; - if (swiotlb_force == SWIOTLB_NO_FORCE) + if (!addressing_limit && !swiotlb_force_bounce) + return; + if (swiotlb_force_disable) return; /* Get IO TLB memory from the low pages */ tlb = memblock_alloc_low(bytes, PAGE_SIZE); if (!tlb) goto fail; - if (swiotlb_init_with_tbl(tlb, default_nslabs, verbose)) + if (swiotlb_init_with_tbl(tlb, default_nslabs, flags)) goto fail_free_mem; return;
@@ -298,7 +302,7 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask) unsigned int order; int rc = 0; - if (swiotlb_force == SWIOTLB_NO_FORCE) + if (swiotlb_force_disable) return 0; /*
@@ -337,7 +341,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) struct io_tlb_mem *mem = &io_tlb_default_mem; unsigned long bytes = nslabs << IO_TLB_SHIFT; - if (swiotlb_force == SWIOTLB_NO_FORCE) + if (swiotlb_force_disable) return 0; /* protect against double initialization */
@@ -362,7 +366,7 @@ void __init swiotlb_exit(void) unsigned long tbl_vaddr; size_t tbl_size, slots_size; - if (swiotlb_force == SWIOTLB_FORCE) + if (swiotlb_force_bounce) return; if (!mem->nslabs)
@@ -708,8 +712,7 @@ dma_addr_t swiotlb_map(struct device *dev, phys_addr_t paddr, size_t size, phys_addr_t swiotlb_addr; dma_addr_t dma_addr; - trace_swiotlb_bounced(dev, phys_to_dma(dev, paddr), size, - swiotlb_force); + trace_swiotlb_bounced(dev, phys_to_dma(dev, paddr), size); swiotlb_addr = swiotlb_tbl_map_single(dev, paddr, size, size, 0, dir, attrs);
--
2.30.2