[PATCH 09/12] swiotlb: make the swiotlb_init interface more useful
From: Christoph Hellwig <hch@lst.de>
Date: 2022-03-01 11:00:29
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, 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), xen hypervisor interface, xen swiotlb subsystem · Maintainers:
Russell King, Catalin Marinas, Will Deacon, Marek Szyprowski, 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, 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/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/pci-dma.c | 15 ++++++----- drivers/xen/swiotlb-xen.c | 4 +-- include/linux/swiotlb.h | 15 ++++++----- include/trace/events/swiotlb.h | 29 ++++++++------------- kernel/dma/swiotlb.c | 35 ++++++++++++++------------ 15 files changed, 55 insertions(+), 82 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/mm/mem.c b/arch/powerpc/mm/mem.c
index 8e301cd8925b2..e1519e2edc656 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, 0); #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/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 7ab7002758396..e0def4b1c3181 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 void __init pci_swiotlb_detect(void) {
@@ -57,16 +58,16 @@ static void __init pci_swiotlb_detect(void) * Guest with guest memory encryption must always do I/O through a * bounce buffer as the hypervisor can't access arbitrary VM memory. */ - if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) - swiotlb_force = SWIOTLB_FORCE; - - if (swiotlb_force == SWIOTLB_FORCE) + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) { x86_swiotlb_enable = true; + x86_swiotlb_flags |= SWIOTLB_FORCE; + } } #else static inline void __init pci_swiotlb_detect(void) { } +#define x86_swiotlb_flags 0 #endif /* CONFIG_SWIOTLB */ #ifdef CONFIG_SWIOTLB_XEN
@@ -74,8 +75,7 @@ static bool xen_swiotlb; static void __init pci_xen_swiotlb_init(void) { - if (!xen_initial_domain() && !x86_swiotlb_enable && - swiotlb_force != SWIOTLB_FORCE) + if (!xen_initial_domain() && !x86_swiotlb_enable) return; x86_swiotlb_enable = false; xen_swiotlb = true;
@@ -119,8 +119,7 @@ void __init pci_iommu_alloc(void) gart_iommu_hole_init(); amd_iommu_detect(); detect_intel_iommu(); - if (x86_swiotlb_enable) - swiotlb_init(0); + swiotlb_init(x86_swiotlb_enable, x86_swiotlb_flags); } /*
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 9a38ea3a46e9f..1a40c71c4d51a 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)
@@ -709,8 +713,7 @@ 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