diff options
Diffstat (limited to 'kernel/drivers/iommu/io-pgtable-arm.c')
| -rw-r--r-- | kernel/drivers/iommu/io-pgtable-arm.c | 139 |
1 files changed, 101 insertions, 38 deletions
diff --git a/kernel/drivers/iommu/io-pgtable-arm.c b/kernel/drivers/iommu/io-pgtable-arm.c index e29d5d7fe..dad768caa 100644 --- a/kernel/drivers/iommu/io-pgtable-arm.c +++ b/kernel/drivers/iommu/io-pgtable-arm.c @@ -26,6 +26,8 @@ #include <linux/slab.h> #include <linux/types.h> +#include <asm/barrier.h> + #include "io-pgtable.h" #define ARM_LPAE_MAX_ADDR_BITS 48 @@ -200,6 +202,64 @@ typedef u64 arm_lpae_iopte; static bool selftest_running = false; +static dma_addr_t __arm_lpae_dma_addr(void *pages) +{ + return (dma_addr_t)virt_to_phys(pages); +} + +static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp, + struct io_pgtable_cfg *cfg) +{ + struct device *dev = cfg->iommu_dev; + dma_addr_t dma; + void *pages = alloc_pages_exact(size, gfp | __GFP_ZERO); + + if (!pages) + return NULL; + + if (!selftest_running) { + dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE); + if (dma_mapping_error(dev, dma)) + goto out_free; + /* + * We depend on the IOMMU being able to work with any physical + * address directly, so if the DMA layer suggests otherwise by + * translating or truncating them, that bodes very badly... + */ + if (dma != virt_to_phys(pages)) + goto out_unmap; + } + + return pages; + +out_unmap: + dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n"); + dma_unmap_single(dev, dma, size, DMA_TO_DEVICE); +out_free: + free_pages_exact(pages, size); + return NULL; +} + +static void __arm_lpae_free_pages(void *pages, size_t size, + struct io_pgtable_cfg *cfg) +{ + if (!selftest_running) + dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages), + size, DMA_TO_DEVICE); + free_pages_exact(pages, size); +} + +static void __arm_lpae_set_pte(arm_lpae_iopte *ptep, arm_lpae_iopte pte, + struct io_pgtable_cfg *cfg) +{ + *ptep = pte; + + if (!selftest_running) + dma_sync_single_for_device(cfg->iommu_dev, + __arm_lpae_dma_addr(ptep), + sizeof(pte), DMA_TO_DEVICE); +} + static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data, unsigned long iova, size_t size, int lvl, arm_lpae_iopte *ptep); @@ -210,6 +270,7 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, arm_lpae_iopte *ptep) { arm_lpae_iopte pte = prot; + struct io_pgtable_cfg *cfg = &data->iop.cfg; if (iopte_leaf(*ptep, lvl)) { /* We require an unmap first */ @@ -228,7 +289,7 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, return -EINVAL; } - if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS) + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) pte |= ARM_LPAE_PTE_NS; if (lvl == ARM_LPAE_MAX_LEVELS - 1) @@ -239,8 +300,7 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data, pte |= ARM_LPAE_PTE_AF | ARM_LPAE_PTE_SH_IS; pte |= pfn_to_iopte(paddr >> data->pg_shift, data); - *ptep = pte; - data->iop.cfg.tlb->flush_pgtable(ptep, sizeof(*ptep), data->iop.cookie); + __arm_lpae_set_pte(ptep, pte, cfg); return 0; } @@ -249,14 +309,14 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova, int lvl, arm_lpae_iopte *ptep) { arm_lpae_iopte *cptep, pte; - void *cookie = data->iop.cookie; size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data); + struct io_pgtable_cfg *cfg = &data->iop.cfg; /* Find our entry at the current level */ ptep += ARM_LPAE_LVL_IDX(iova, lvl, data); /* If we can install a leaf entry at this level, then do so */ - if (size == block_size && (size & data->iop.cfg.pgsize_bitmap)) + if (size == block_size && (size & cfg->pgsize_bitmap)) return arm_lpae_init_pte(data, iova, paddr, prot, lvl, ptep); /* We can't allocate tables at the final level */ @@ -266,18 +326,15 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova, /* Grab a pointer to the next level */ pte = *ptep; if (!pte) { - cptep = alloc_pages_exact(1UL << data->pg_shift, - GFP_ATOMIC | __GFP_ZERO); + cptep = __arm_lpae_alloc_pages(1UL << data->pg_shift, + GFP_ATOMIC, cfg); if (!cptep) return -ENOMEM; - data->iop.cfg.tlb->flush_pgtable(cptep, 1UL << data->pg_shift, - cookie); pte = __pa(cptep) | ARM_LPAE_PTE_TYPE_TABLE; - if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS) + if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) pte |= ARM_LPAE_PTE_NSTABLE; - *ptep = pte; - data->iop.cfg.tlb->flush_pgtable(ptep, sizeof(*ptep), cookie); + __arm_lpae_set_pte(ptep, pte, cfg); } else { cptep = iopte_deref(pte, data); } @@ -324,7 +381,7 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova, { struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops); arm_lpae_iopte *ptep = data->pgd; - int lvl = ARM_LPAE_START_LVL(data); + int ret, lvl = ARM_LPAE_START_LVL(data); arm_lpae_iopte prot; /* If no access, then nothing to do */ @@ -332,7 +389,14 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova, return 0; prot = arm_lpae_prot_to_pte(data, iommu_prot); - return __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep); + ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep); + /* + * Synchronise all PTE updates for the new mapping before there's + * a chance for anything to kick off a table walk for the new iova. + */ + wmb(); + + return ret; } static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl, @@ -341,17 +405,18 @@ static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl, arm_lpae_iopte *start, *end; unsigned long table_size; - /* Only leaf entries at the last level */ - if (lvl == ARM_LPAE_MAX_LEVELS - 1) - return; - if (lvl == ARM_LPAE_START_LVL(data)) table_size = data->pgd_size; else table_size = 1UL << data->pg_shift; start = ptep; - end = (void *)ptep + table_size; + + /* Only leaf entries at the last level */ + if (lvl == ARM_LPAE_MAX_LEVELS - 1) + end = ptep; + else + end = (void *)ptep + table_size; while (ptep != end) { arm_lpae_iopte pte = *ptep++; @@ -362,7 +427,7 @@ static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl, __arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data)); } - free_pages_exact(start, table_size); + __arm_lpae_free_pages(start, table_size, &data->iop.cfg); } static void arm_lpae_free_pgtable(struct io_pgtable *iop) @@ -381,8 +446,7 @@ static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data, unsigned long blk_start, blk_end; phys_addr_t blk_paddr; arm_lpae_iopte table = 0; - void *cookie = data->iop.cookie; - const struct iommu_gather_ops *tlb = data->iop.cfg.tlb; + struct io_pgtable_cfg *cfg = &data->iop.cfg; blk_start = iova & ~(blk_size - 1); blk_end = blk_start + blk_size; @@ -408,10 +472,9 @@ static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data, } } - *ptep = table; - tlb->flush_pgtable(ptep, sizeof(*ptep), cookie); + __arm_lpae_set_pte(ptep, table, cfg); iova &= ~(blk_size - 1); - tlb->tlb_add_flush(iova, blk_size, true, cookie); + cfg->tlb->tlb_add_flush(iova, blk_size, true, data->iop.cookie); return size; } @@ -433,13 +496,12 @@ static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data, /* If the size matches this level, we're in the right place */ if (size == blk_size) { - *ptep = 0; - tlb->flush_pgtable(ptep, sizeof(*ptep), cookie); + __arm_lpae_set_pte(ptep, 0, &data->iop.cfg); if (!iopte_leaf(pte, lvl)) { /* Also flush any partial walks */ tlb->tlb_add_flush(iova, size, false, cookie); - tlb->tlb_sync(data->iop.cookie); + tlb->tlb_sync(cookie); ptep = iopte_deref(pte, data); __arm_lpae_free_pgtable(data, lvl + 1, ptep); } else { @@ -565,6 +627,11 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg) if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS) return NULL; + if (!selftest_running && cfg->iommu_dev->dma_pfn_offset) { + dev_err(cfg->iommu_dev, "Cannot accommodate DMA offset for IOMMU page tables\n"); + return NULL; + } + data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data) return NULL; @@ -655,11 +722,12 @@ arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie) cfg->arm_lpae_s1_cfg.mair[1] = 0; /* Looking good; allocate a pgd */ - data->pgd = alloc_pages_exact(data->pgd_size, GFP_KERNEL | __GFP_ZERO); + data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg); if (!data->pgd) goto out_free_data; - cfg->tlb->flush_pgtable(data->pgd, data->pgd_size, cookie); + /* Ensure the empty pgd is visible before any actual TTBR write */ + wmb(); /* TTBRs */ cfg->arm_lpae_s1_cfg.ttbr[0] = virt_to_phys(data->pgd); @@ -743,11 +811,12 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie) cfg->arm_lpae_s2_cfg.vtcr = reg; /* Allocate pgd pages */ - data->pgd = alloc_pages_exact(data->pgd_size, GFP_KERNEL | __GFP_ZERO); + data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg); if (!data->pgd) goto out_free_data; - cfg->tlb->flush_pgtable(data->pgd, data->pgd_size, cookie); + /* Ensure the empty pgd is visible before any actual TTBR write */ + wmb(); /* VTTBR */ cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd); @@ -833,16 +902,10 @@ static void dummy_tlb_sync(void *cookie) WARN_ON(cookie != cfg_cookie); } -static void dummy_flush_pgtable(void *ptr, size_t size, void *cookie) -{ - WARN_ON(cookie != cfg_cookie); -} - static struct iommu_gather_ops dummy_tlb_ops __initdata = { .tlb_flush_all = dummy_tlb_flush_all, .tlb_add_flush = dummy_tlb_add_flush, .tlb_sync = dummy_tlb_sync, - .flush_pgtable = dummy_flush_pgtable, }; static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops) |