From 69031f500865ee3eee19566a1b9c40a189817eaa Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:34 +0800 Subject: swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Always have the pointer to the swiotlb pool used in struct device. This could help simplify the code for other pools. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/device.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/device.h b/include/linux/device.h index 59940f1744c1..2a22875238a6 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -423,6 +423,7 @@ struct dev_links_info { * @dma_pools: Dma pools (if dma'ble device). * @dma_mem: Internal for coherent mem override. * @cma_area: Contiguous memory area for dma allocations + * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use. * @archdata: For arch-specific additions. * @of_node: Associated device tree node. * @fwnode: Associated device node supplied by platform firmware. @@ -531,6 +532,9 @@ struct device { #ifdef CONFIG_DMA_CMA struct cma *cma_area; /* contiguous memory area for dma allocations */ +#endif +#ifdef CONFIG_SWIOTLB + struct io_tlb_mem *dma_io_tlb_mem; #endif /* arch specific additions */ struct dev_archdata archdata; -- cgit v1.2.3 From 7fd856aa7f4261ddac62ea59d8383fef22a0690e Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:35 +0800 Subject: swiotlb: Update is_swiotlb_buffer to add a struct device argument Update is_swiotlb_buffer to add a struct device argument. This will be useful later to allow for different pools. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/swiotlb.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 216854a5e513..d1f3d95881cd 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -2,6 +2,7 @@ #ifndef __LINUX_SWIOTLB_H #define __LINUX_SWIOTLB_H +#include #include #include #include @@ -101,9 +102,9 @@ struct io_tlb_mem { }; extern struct io_tlb_mem *io_tlb_default_mem; -static inline bool is_swiotlb_buffer(phys_addr_t paddr) +static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) { - struct io_tlb_mem *mem = io_tlb_default_mem; + struct io_tlb_mem *mem = dev->dma_io_tlb_mem; return mem && paddr >= mem->start && paddr < mem->end; } @@ -115,7 +116,7 @@ bool is_swiotlb_active(void); void __init swiotlb_adjust_size(unsigned long size); #else #define swiotlb_force SWIOTLB_NO_FORCE -static inline bool is_swiotlb_buffer(phys_addr_t paddr) +static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) { return false; } -- cgit v1.2.3 From 6f2beb268a5d35504a636c4a3b7aaa76ec32d96c Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:36 +0800 Subject: swiotlb: Update is_swiotlb_active to add a struct device argument Update is_swiotlb_active to add a struct device argument. This will be useful later to allow for different pools. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/swiotlb.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index d1f3d95881cd..dd1c30a83058 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -112,7 +112,7 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) void __init swiotlb_exit(void); unsigned int swiotlb_max_segment(void); size_t swiotlb_max_mapping_size(struct device *dev); -bool is_swiotlb_active(void); +bool is_swiotlb_active(struct device *dev); void __init swiotlb_adjust_size(unsigned long size); #else #define swiotlb_force SWIOTLB_NO_FORCE @@ -132,7 +132,7 @@ static inline size_t swiotlb_max_mapping_size(struct device *dev) return SIZE_MAX; } -static inline bool is_swiotlb_active(void) +static inline bool is_swiotlb_active(struct device *dev) { return false; } -- cgit v1.2.3 From 903cd0f315fe426c6a64c54ed389de0becb663dc Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Thu, 24 Jun 2021 23:55:20 +0800 Subject: swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Propagate the swiotlb_force into io_tlb_default_mem->force_bounce and use it to determine whether to bounce the data or not. This will be useful later to allow for different pools. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk [v2: Includes Will's fix] --- include/linux/swiotlb.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index dd1c30a83058..da348671b0d5 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -84,6 +84,7 @@ extern enum swiotlb_force swiotlb_force; * unmap calls. * @debugfs: The dentry to debugfs. * @late_alloc: %true if allocated using the page allocator + * @force_bounce: %true if swiotlb bouncing is forced */ struct io_tlb_mem { phys_addr_t start; @@ -94,6 +95,7 @@ struct io_tlb_mem { spinlock_t lock; struct dentry *debugfs; bool late_alloc; + bool force_bounce; struct io_tlb_slot { phys_addr_t orig_addr; size_t alloc_size; @@ -109,6 +111,13 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) return mem && paddr >= mem->start && paddr < mem->end; } +static inline bool is_swiotlb_force_bounce(struct device *dev) +{ + struct io_tlb_mem *mem = dev->dma_io_tlb_mem; + + return mem && mem->force_bounce; +} + void __init swiotlb_exit(void); unsigned int swiotlb_max_segment(void); size_t swiotlb_max_mapping_size(struct device *dev); @@ -120,6 +129,10 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) { return false; } +static inline bool is_swiotlb_force_bounce(struct device *dev) +{ + return false; +} static inline void swiotlb_exit(void) { } -- cgit v1.2.3 From f4111e39a52aa5d5136d890bbd1aa87c1c8fe3bc Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:40 +0800 Subject: swiotlb: Add restricted DMA alloc/free support Add the functions, swiotlb_{alloc,free} and is_swiotlb_for_alloc to support the memory allocation from restricted DMA pool. The restricted DMA pool is preferred if available. Note that since coherent allocation needs remapping, one must set up another device coherent pool by shared-dma-pool and use dma_alloc_from_dev_coherent instead for atomic coherent allocation. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/swiotlb.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index da348671b0d5..3b9454d1e498 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force; * @debugfs: The dentry to debugfs. * @late_alloc: %true if allocated using the page allocator * @force_bounce: %true if swiotlb bouncing is forced + * @for_alloc: %true if the pool is used for memory allocation */ struct io_tlb_mem { phys_addr_t start; @@ -96,6 +97,7 @@ struct io_tlb_mem { struct dentry *debugfs; bool late_alloc; bool force_bounce; + bool for_alloc; struct io_tlb_slot { phys_addr_t orig_addr; size_t alloc_size; @@ -158,4 +160,28 @@ static inline void swiotlb_adjust_size(unsigned long size) extern void swiotlb_print_info(void); extern void swiotlb_set_max_segment(unsigned int); +#ifdef CONFIG_DMA_RESTRICTED_POOL +struct page *swiotlb_alloc(struct device *dev, size_t size); +bool swiotlb_free(struct device *dev, struct page *page, size_t size); + +static inline bool is_swiotlb_for_alloc(struct device *dev) +{ + return dev->dma_io_tlb_mem->for_alloc; +} +#else +static inline struct page *swiotlb_alloc(struct device *dev, size_t size) +{ + return NULL; +} +static inline bool swiotlb_free(struct device *dev, struct page *page, + size_t size) +{ + return false; +} +static inline bool is_swiotlb_for_alloc(struct device *dev) +{ + return false; +} +#endif /* CONFIG_DMA_RESTRICTED_POOL */ + #endif /* __LINUX_SWIOTLB_H */ -- cgit v1.2.3 From 0b84e4f8b793eb4045fd64f6f514165a7974cd16 Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:41 +0800 Subject: swiotlb: Add restricted DMA pool initialization Add the initialization function to create restricted DMA pools from matching reserved-memory nodes. Regardless of swiotlb setting, the restricted DMA pool is preferred if available. The restricted DMA pools provide a basic level of protection against the DMA overwriting buffer contents at unexpected times. However, to protect against general data leakage and system memory corruption, the system needs to provide a way to lock down the memory access, e.g., MPU. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/swiotlb.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 3b9454d1e498..39284ff2a6cd 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -73,7 +73,8 @@ extern enum swiotlb_force swiotlb_force; * range check to see if the memory was in fact allocated by this * API. * @nslabs: The number of IO TLB blocks (in groups of 64) between @start and - * @end. This is command line adjustable via setup_io_tlb_npages. + * @end. For default swiotlb, this is command line adjustable via + * setup_io_tlb_npages. * @used: The number of used IO TLB block. * @list: The free list describing the number of free entries available * from each index. -- cgit v1.2.3 From 463e862ac63ef27fca423782536f6465abc3f180 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 20 Jul 2021 14:38:24 +0100 Subject: swiotlb: Convert io_default_tlb_mem to static allocation Since commit 69031f500865 ("swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used"), 'struct device' may hold a copy of the global 'io_default_tlb_mem' pointer if the device is using swiotlb for DMA. A subsequent call to swiotlb_exit() will therefore leave dangling pointers behind in these device structures, resulting in KASAN splats such as: | BUG: KASAN: use-after-free in __iommu_dma_unmap_swiotlb+0x64/0xb0 | Read of size 8 at addr ffff8881d7830000 by task swapper/0/0 | | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc3-debug #1 | Hardware name: HP HP Desktop M01-F1xxx/87D6, BIOS F.12 12/17/2020 | Call Trace: | | dump_stack+0x9c/0xcf | print_address_description.constprop.0+0x18/0x130 | kasan_report.cold+0x7f/0x111 | __iommu_dma_unmap_swiotlb+0x64/0xb0 | nvme_pci_complete_rq+0x73/0x130 | blk_complete_reqs+0x6f/0x80 | __do_softirq+0xfc/0x3be Convert 'io_default_tlb_mem' to a static structure, so that the per-device pointers remain valid after swiotlb_exit() has been invoked. All users are updated to reference the static structure directly, using the 'nslabs' field to determine whether swiotlb has been initialised. The 'slots' array is still allocated dynamically and referenced via a pointer rather than a flexible array member. Cc: Claire Chang Cc: Christoph Hellwig Cc: Robin Murphy Cc: Konrad Rzeszutek Wilk Fixes: 69031f500865 ("swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used") Reported-by: Nathan Chancellor Tested-by: Nathan Chancellor Tested-by: Claire Chang Reviewed-by: Christoph Hellwig Signed-off-by: Will Deacon Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/swiotlb.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 39284ff2a6cd..b0cb2a9973f4 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -103,9 +103,9 @@ struct io_tlb_mem { phys_addr_t orig_addr; size_t alloc_size; unsigned int list; - } slots[]; + } *slots; }; -extern struct io_tlb_mem *io_tlb_default_mem; +extern struct io_tlb_mem io_tlb_default_mem; static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr) { -- cgit v1.2.3