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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-26 13:59:32 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-26 13:59:32 -0800 |
commit | ef9856a734af9bc71e5a8554374380e200fe7fc4 (patch) | |
tree | 10375ea7224963d8f9af16495eefa360920a1098 /kernel/dma | |
parent | fecfd015394e9151f535d675e115fba967bddb3f (diff) | |
parent | daf9514fd5eb098d7d6f3a1247cb8cc48fc94155 (diff) | |
download | linux-ef9856a734af9bc71e5a8554374380e200fe7fc4.tar.bz2 |
Merge branch 'stable/for-linus-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb updates from Konrad Rzeszutek Wilk:
"Two memory encryption related patches (SWIOTLB is enabled by default
for AMD-SEV):
- Add support for alignment so that NVME can properly work
- Keep track of requested DMA buffers length, as underlaying hardware
devices can trip SWIOTLB to bounce too much and crash the kernel
And a tiny fix to use proper APIs in drivers"
* 'stable/for-linus-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: Validate bounce size in the sync/unmap path
nvme-pci: set min_align_mask
swiotlb: respect min_align_mask
swiotlb: don't modify orig_addr in swiotlb_tbl_sync_single
swiotlb: refactor swiotlb_tbl_map_single
swiotlb: clean up swiotlb_tbl_unmap_single
swiotlb: factor out a nr_slots helper
swiotlb: factor out an io_tlb_offset helper
swiotlb: add a IO_TLB_SIZE define
driver core: add a min_align_mask field to struct device_dma_parameters
sdhci: stop poking into swiotlb internals
Diffstat (limited to 'kernel/dma')
-rw-r--r-- | kernel/dma/swiotlb.c | 310 |
1 files changed, 194 insertions, 116 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 7c42df6e6100..c10e855a03bc 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -50,9 +50,6 @@ #define CREATE_TRACE_POINTS #include <trace/events/swiotlb.h> -#define OFFSET(val,align) ((unsigned long) \ - ( (val) & ( (align) - 1))) - #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) /* @@ -103,6 +100,11 @@ static unsigned int max_segment; static phys_addr_t *io_tlb_orig_addr; /* + * The mapped buffer's size should be validated during a sync operation. + */ +static size_t *io_tlb_orig_size; + +/* * Protect the above data structures in the map and unmap calls */ static DEFINE_SPINLOCK(io_tlb_lock); @@ -171,7 +173,7 @@ void __init swiotlb_adjust_size(unsigned long new_size) * adjust/expand SWIOTLB size for their use. */ if (!io_tlb_nslabs) { - size = ALIGN(new_size, 1 << IO_TLB_SHIFT); + size = ALIGN(new_size, IO_TLB_SIZE); io_tlb_nslabs = size >> IO_TLB_SHIFT; io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); @@ -192,6 +194,16 @@ void swiotlb_print_info(void) bytes >> 20); } +static inline unsigned long io_tlb_offset(unsigned long val) +{ + return val & (IO_TLB_SEGSIZE - 1); +} + +static inline unsigned long nr_slots(u64 val) +{ + return DIV_ROUND_UP(val, IO_TLB_SIZE); +} + /* * Early SWIOTLB allocation may be too early to allow an architecture to * perform the desired operations. This function allows the architecture to @@ -240,9 +252,16 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) panic("%s: Failed to allocate %zu bytes align=0x%lx\n", __func__, alloc_size, PAGE_SIZE); + alloc_size = PAGE_ALIGN(io_tlb_nslabs * sizeof(size_t)); + io_tlb_orig_size = memblock_alloc(alloc_size, PAGE_SIZE); + if (!io_tlb_orig_size) + panic("%s: Failed to allocate %zu bytes align=0x%lx\n", + __func__, alloc_size, PAGE_SIZE); + for (i = 0; i < io_tlb_nslabs; i++) { - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); + io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i); io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + io_tlb_orig_size[i] = 0; } io_tlb_index = 0; no_iotlb_memory = false; @@ -363,7 +382,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) * between io_tlb_start and io_tlb_end. */ io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, - get_order(io_tlb_nslabs * sizeof(int))); + get_order(io_tlb_nslabs * sizeof(int))); if (!io_tlb_list) goto cleanup3; @@ -374,9 +393,18 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) if (!io_tlb_orig_addr) goto cleanup4; + io_tlb_orig_size = (size_t *) + __get_free_pages(GFP_KERNEL, + get_order(io_tlb_nslabs * + sizeof(size_t))); + if (!io_tlb_orig_size) + goto cleanup5; + + for (i = 0; i < io_tlb_nslabs; i++) { - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); + io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i); io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + io_tlb_orig_size[i] = 0; } io_tlb_index = 0; no_iotlb_memory = false; @@ -389,6 +417,10 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) return 0; +cleanup5: + free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * + sizeof(phys_addr_t))); + cleanup4: free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * sizeof(int))); @@ -404,6 +436,8 @@ void __init swiotlb_exit(void) return; if (late_alloc) { + free_pages((unsigned long)io_tlb_orig_size, + get_order(io_tlb_nslabs * sizeof(size_t))); free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * sizeof(phys_addr_t))); free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * @@ -413,6 +447,8 @@ void __init swiotlb_exit(void) } else { memblock_free_late(__pa(io_tlb_orig_addr), PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); + memblock_free_late(__pa(io_tlb_orig_size), + PAGE_ALIGN(io_tlb_nslabs * sizeof(size_t))); memblock_free_late(__pa(io_tlb_list), PAGE_ALIGN(io_tlb_nslabs * sizeof(int))); memblock_free_late(io_tlb_start, @@ -461,79 +497,71 @@ static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, } } -phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr, - size_t mapping_size, size_t alloc_size, - enum dma_data_direction dir, unsigned long attrs) -{ - dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(hwdev, io_tlb_start); - unsigned long flags; - phys_addr_t tlb_addr; - unsigned int nslots, stride, index, wrap; - int i; - unsigned long mask; - unsigned long offset_slots; - unsigned long max_slots; - unsigned long tmp_io_tlb_used; - - if (no_iotlb_memory) - panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); - - if (mem_encrypt_active()) - pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n"); +#define slot_addr(start, idx) ((start) + ((idx) << IO_TLB_SHIFT)) - if (mapping_size > alloc_size) { - dev_warn_once(hwdev, "Invalid sizes (mapping: %zd bytes, alloc: %zd bytes)", - mapping_size, alloc_size); - return (phys_addr_t)DMA_MAPPING_ERROR; - } +/* + * Return the offset into a iotlb slot required to keep the device happy. + */ +static unsigned int swiotlb_align_offset(struct device *dev, u64 addr) +{ + return addr & dma_get_min_align_mask(dev) & (IO_TLB_SIZE - 1); +} - mask = dma_get_seg_boundary(hwdev); +/* + * Carefully handle integer overflow which can occur when boundary_mask == ~0UL. + */ +static inline unsigned long get_max_slots(unsigned long boundary_mask) +{ + if (boundary_mask == ~0UL) + return 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); + return nr_slots(boundary_mask + 1); +} - tbl_dma_addr &= mask; +static unsigned int wrap_index(unsigned int index) +{ + if (index >= io_tlb_nslabs) + return 0; + return index; +} - offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; +/* + * Find a suitable number of IO TLB entries size that will fit this request and + * allocate a buffer from that IO TLB pool. + */ +static int find_slots(struct device *dev, phys_addr_t orig_addr, + size_t alloc_size) +{ + unsigned long boundary_mask = dma_get_seg_boundary(dev); + dma_addr_t tbl_dma_addr = + phys_to_dma_unencrypted(dev, io_tlb_start) & boundary_mask; + unsigned long max_slots = get_max_slots(boundary_mask); + unsigned int iotlb_align_mask = + dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1); + unsigned int nslots = nr_slots(alloc_size), stride; + unsigned int index, wrap, count = 0, i; + unsigned long flags; - /* - * Carefully handle integer overflow which can occur when mask == ~0UL. - */ - max_slots = mask + 1 - ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT - : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); + BUG_ON(!nslots); /* - * For mappings greater than or equal to a page, we limit the stride - * (and hence alignment) to a page size. + * For mappings with an alignment requirement don't bother looping to + * unaligned slots once we found an aligned one. For allocations of + * PAGE_SIZE or larger only look for page aligned allocations. */ - nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; + stride = (iotlb_align_mask >> IO_TLB_SHIFT) + 1; if (alloc_size >= PAGE_SIZE) - stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); - else - stride = 1; - - BUG_ON(!nslots); + stride = max(stride, stride << (PAGE_SHIFT - IO_TLB_SHIFT)); - /* - * Find suitable number of IO TLB entries size that will fit this - * request and allocate a buffer from that IO TLB pool. - */ spin_lock_irqsave(&io_tlb_lock, flags); - if (unlikely(nslots > io_tlb_nslabs - io_tlb_used)) goto not_found; - index = ALIGN(io_tlb_index, stride); - if (index >= io_tlb_nslabs) - index = 0; - wrap = index; - + index = wrap = wrap_index(ALIGN(io_tlb_index, stride)); do { - while (iommu_is_span_boundary(index, nslots, offset_slots, - max_slots)) { - index += stride; - if (index >= io_tlb_nslabs) - index = 0; - if (index == wrap) - goto not_found; + if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) != + (orig_addr & iotlb_align_mask)) { + index = wrap_index(index + 1); + continue; } /* @@ -541,55 +569,96 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr, * contiguous buffers, we allocate the buffers from that slot * and mark the entries as '0' indicating unavailable. */ - if (io_tlb_list[index] >= nslots) { - int count = 0; - - for (i = index; i < (int) (index + nslots); i++) - io_tlb_list[i] = 0; - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--) - io_tlb_list[i] = ++count; - tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT); - - /* - * Update the indices to avoid searching in the next - * round. - */ - io_tlb_index = ((index + nslots) < io_tlb_nslabs - ? (index + nslots) : 0); - - goto found; + if (!iommu_is_span_boundary(index, nslots, + nr_slots(tbl_dma_addr), + max_slots)) { + if (io_tlb_list[index] >= nslots) + goto found; } - index += stride; - if (index >= io_tlb_nslabs) - index = 0; + index = wrap_index(index + stride); } while (index != wrap); not_found: - tmp_io_tlb_used = io_tlb_used; - spin_unlock_irqrestore(&io_tlb_lock, flags); - if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) - dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", - alloc_size, io_tlb_nslabs, tmp_io_tlb_used); - return (phys_addr_t)DMA_MAPPING_ERROR; + return -1; + found: + for (i = index; i < index + nslots; i++) + io_tlb_list[i] = 0; + for (i = index - 1; + io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && + io_tlb_list[i]; i--) + io_tlb_list[i] = ++count; + + /* + * Update the indices to avoid searching in the next round. + */ + if (index + nslots < io_tlb_nslabs) + io_tlb_index = index + nslots; + else + io_tlb_index = 0; io_tlb_used += nslots; + spin_unlock_irqrestore(&io_tlb_lock, flags); + return index; +} + +phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, + size_t mapping_size, size_t alloc_size, + enum dma_data_direction dir, unsigned long attrs) +{ + unsigned int offset = swiotlb_align_offset(dev, orig_addr); + unsigned int index, i; + phys_addr_t tlb_addr; + + if (no_iotlb_memory) + panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); + + if (mem_encrypt_active()) + pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n"); + + if (mapping_size > alloc_size) { + dev_warn_once(dev, "Invalid sizes (mapping: %zd bytes, alloc: %zd bytes)", + mapping_size, alloc_size); + return (phys_addr_t)DMA_MAPPING_ERROR; + } + + index = find_slots(dev, orig_addr, alloc_size + offset); + if (index == -1) { + if (!(attrs & DMA_ATTR_NO_WARN)) + dev_warn_ratelimited(dev, + "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", + alloc_size, io_tlb_nslabs, io_tlb_used); + return (phys_addr_t)DMA_MAPPING_ERROR; + } /* * Save away the mapping from the original address to the DMA address. * This is needed when we sync the memory. Then we sync the buffer if * needed. */ - for (i = 0; i < nslots; i++) - io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT); + for (i = 0; i < nr_slots(alloc_size + offset); i++) { + io_tlb_orig_addr[index + i] = slot_addr(orig_addr, i); + io_tlb_orig_size[index+i] = alloc_size - (i << IO_TLB_SHIFT); + } + tlb_addr = slot_addr(io_tlb_start, index) + offset; if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); - return tlb_addr; } +static void validate_sync_size_and_truncate(struct device *hwdev, size_t orig_size, size_t *size) +{ + if (*size > orig_size) { + /* Warn and truncate mapping_size */ + dev_WARN_ONCE(hwdev, 1, + "Attempt for buffer overflow. Original size: %zu. Mapping size: %zu.\n", + orig_size, *size); + *size = orig_size; + } +} + /* * tlb_addr is the physical address of the bounce buffer to unmap. */ @@ -598,10 +667,13 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, enum dma_data_direction dir, unsigned long attrs) { unsigned long flags; - int i, count, nslots = ALIGN(alloc_size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; + unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr); + int i, count, nslots = nr_slots(alloc_size + offset); + int index = (tlb_addr - offset - io_tlb_start) >> IO_TLB_SHIFT; phys_addr_t orig_addr = io_tlb_orig_addr[index]; + validate_sync_size_and_truncate(hwdev, io_tlb_orig_size[index], &mapping_size); + /* * First, sync the memory before unmapping the entry */ @@ -617,26 +689,30 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, * with slots below and above the pool being returned. */ spin_lock_irqsave(&io_tlb_lock, flags); - { - count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ? - io_tlb_list[index + nslots] : 0); - /* - * Step 1: return the slots to the free list, merging the - * slots with superceeding slots - */ - for (i = index + nslots - 1; i >= index; i--) { - io_tlb_list[i] = ++count; - io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; - } - /* - * Step 2: merge the returned slots with the preceding slots, - * if available (non zero) - */ - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) - io_tlb_list[i] = ++count; + if (index + nslots < ALIGN(index + 1, IO_TLB_SEGSIZE)) + count = io_tlb_list[index + nslots]; + else + count = 0; - io_tlb_used -= nslots; + /* + * Step 1: return the slots to the free list, merging the slots with + * superceeding slots + */ + for (i = index + nslots - 1; i >= index; i--) { + io_tlb_list[i] = ++count; + io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + io_tlb_orig_size[i] = 0; } + + /* + * Step 2: merge the returned slots with the preceding slots, if + * available (non zero) + */ + for (i = index - 1; + io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && io_tlb_list[i]; + i--) + io_tlb_list[i] = ++count; + io_tlb_used -= nslots; spin_unlock_irqrestore(&io_tlb_lock, flags); } @@ -645,11 +721,13 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr, enum dma_sync_target target) { int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; + size_t orig_size = io_tlb_orig_size[index]; phys_addr_t orig_addr = io_tlb_orig_addr[index]; if (orig_addr == INVALID_PHYS_ADDR) return; - orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1); + + validate_sync_size_and_truncate(hwdev, orig_size, &size); switch (target) { case SYNC_FOR_CPU: @@ -707,7 +785,7 @@ dma_addr_t swiotlb_map(struct device *dev, phys_addr_t paddr, size_t size, size_t swiotlb_max_mapping_size(struct device *dev) { - return ((size_t)1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE; + return ((size_t)IO_TLB_SIZE) * IO_TLB_SEGSIZE; } bool is_swiotlb_active(void) |