/* * CPU-agnostic ARM page table allocator. * * ARMv7 Short-descriptor format, supporting * - Basic memory attributes * - Simplified access permissions (AP[2:1] model) * - Backwards-compatible TEX remap * - Large pages/supersections (if indicated by the caller) * * Not supporting: * - Legacy access permissions (AP[2:0] model) * * Almost certainly never supporting: * - PXN * - Domains * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. * * Copyright (C) 2014-2015 ARM Limited * Copyright (c) 2014-2015 MediaTek Inc. */ #define pr_fmt(fmt) "arm-v7s io-pgtable: " fmt #include <linux/atomic.h> #include <linux/dma-mapping.h> #include <linux/gfp.h> #include <linux/iommu.h> #include <linux/kernel.h> #include <linux/kmemleak.h> #include <linux/sizes.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/types.h> #include <asm/barrier.h> #include "io-pgtable.h" /* Struct accessors */ #define io_pgtable_to_data(x) \ container_of((x), struct arm_v7s_io_pgtable, iop) #define io_pgtable_ops_to_data(x) \ io_pgtable_to_data(io_pgtable_ops_to_pgtable(x)) /* * We have 32 bits total; 12 bits resolved at level 1, 8 bits at level 2, * and 12 bits in a page. With some carefully-chosen coefficients we can * hide the ugly inconsistencies behind these macros and at least let the * rest of the code pretend to be somewhat sane. */ #define ARM_V7S_ADDR_BITS 32 #define _ARM_V7S_LVL_BITS(lvl) (16 - (lvl) * 4) #define ARM_V7S_LVL_SHIFT(lvl) (ARM_V7S_ADDR_BITS - (4 + 8 * (lvl))) #define ARM_V7S_TABLE_SHIFT 10 #define ARM_V7S_PTES_PER_LVL(lvl) (1 << _ARM_V7S_LVL_BITS(lvl)) #define ARM_V7S_TABLE_SIZE(lvl) \ (ARM_V7S_PTES_PER_LVL(lvl) * sizeof(arm_v7s_iopte)) #define ARM_V7S_BLOCK_SIZE(lvl) (1UL << ARM_V7S_LVL_SHIFT(lvl)) #define ARM_V7S_LVL_MASK(lvl) ((u32)(~0U << ARM_V7S_LVL_SHIFT(lvl))) #define ARM_V7S_TABLE_MASK ((u32)(~0U << ARM_V7S_TABLE_SHIFT)) #define _ARM_V7S_IDX_MASK(lvl) (ARM_V7S_PTES_PER_LVL(lvl) - 1) #define ARM_V7S_LVL_IDX(addr, lvl) ({ \ int _l = lvl; \ ((u32)(addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l); \ }) /* * Large page/supersection entries are effectively a block of 16 page/section * entries, along the lines of the LPAE contiguous hint, but all with the * same output address. For want of a better common name we'll call them * "contiguous" versions of their respective page/section entries here, but * noting the distinction (WRT to TLB maintenance) that they represent *one* * entry repeated 16 times, not 16 separate entries (as in the LPAE case). */ #define ARM_V7S_CONT_PAGES 16 /* PTE type bits: these are all mixed up with XN/PXN bits in most cases */ #define ARM_V7S_PTE_TYPE_TABLE 0x1 #define ARM_V7S_PTE_TYPE_PAGE 0x2 #define ARM_V7S_PTE_TYPE_CONT_PAGE 0x1 #define ARM_V7S_PTE_IS_VALID(pte) (((pte) & 0x3) != 0) #define ARM_V7S_PTE_IS_TABLE(pte, lvl) \ ((lvl) == 1 && (((pte) & 0x3) == ARM_V7S_PTE_TYPE_TABLE)) /* Page table bits */ #define ARM_V7S_ATTR_XN(lvl) BIT(4 * (2 - (lvl))) #define ARM_V7S_ATTR_B BIT(2) #define ARM_V7S_ATTR_C BIT(3) #define ARM_V7S_ATTR_NS_TABLE BIT(3) #define ARM_V7S_ATTR_NS_SECTION BIT(19) #define ARM_V7S_CONT_SECTION BIT(18) #define ARM_V7S_CONT_PAGE_XN_SHIFT 15 /* * The attribute bits are consistently ordered*, but occupy bits [17:10] of * a level 1 PTE vs. bits [11:4] at level 2. Thus we define the individual * fields relative to that 8-bit block, plus a total shift relative to the PTE. */ #define ARM_V7S_ATTR_SHIFT(lvl) (16 - (lvl) * 6) #define ARM_V7S_ATTR_MASK 0xff #define ARM_V7S_ATTR_AP0 BIT(0) #define ARM_V7S_ATTR_AP1 BIT(1) #define ARM_V7S_ATTR_AP2 BIT(5) #define ARM_V7S_ATTR_S BIT(6) #define ARM_V7S_ATTR_NG BIT(7) #define ARM_V7S_TEX_SHIFT 2 #define ARM_V7S_TEX_MASK 0x7 #define ARM_V7S_ATTR_TEX(val) (((val) & ARM_V7S_TEX_MASK) << ARM_V7S_TEX_SHIFT) #define ARM_V7S_ATTR_MTK_4GB BIT(9) /* MTK extend it for 4GB mode */ /* *well, except for TEX on level 2 large pages, of course :( */ #define ARM_V7S_CONT_PAGE_TEX_SHIFT 6 #define ARM_V7S_CONT_PAGE_TEX_MASK (ARM_V7S_TEX_MASK << ARM_V7S_CONT_PAGE_TEX_SHIFT) /* Simplified access permissions */ #define ARM_V7S_PTE_AF ARM_V7S_ATTR_AP0 #define ARM_V7S_PTE_AP_UNPRIV ARM_V7S_ATTR_AP1 #define ARM_V7S_PTE_AP_RDONLY ARM_V7S_ATTR_AP2 /* Register bits */ #define ARM_V7S_RGN_NC 0 #define ARM_V7S_RGN_WBWA 1 #define ARM_V7S_RGN_WT 2 #define ARM_V7S_RGN_WB 3 #define ARM_V7S_PRRR_TYPE_DEVICE 1 #define ARM_V7S_PRRR_TYPE_NORMAL 2 #define ARM_V7S_PRRR_TR(n, type) (((type) & 0x3) << ((n) * 2)) #define ARM_V7S_PRRR_DS0 BIT(16) #define ARM_V7S_PRRR_DS1 BIT(17) #define ARM_V7S_PRRR_NS0 BIT(18) #define ARM_V7S_PRRR_NS1 BIT(19) #define ARM_V7S_PRRR_NOS(n) BIT((n) + 24) #define ARM_V7S_NMRR_IR(n, attr) (((attr) & 0x3) << ((n) * 2)) #define ARM_V7S_NMRR_OR(n, attr) (((attr) & 0x3) << ((n) * 2 + 16)) #define ARM_V7S_TTBR_S BIT(1) #define ARM_V7S_TTBR_NOS BIT(5) #define ARM_V7S_TTBR_ORGN_ATTR(attr) (((attr) & 0x3) << 3) #define ARM_V7S_TTBR_IRGN_ATTR(attr) \ ((((attr) & 0x1) << 6) | (((attr) & 0x2) >> 1)) #define ARM_V7S_TCR_PD1 BIT(5) typedef u32 arm_v7s_iopte; static bool selftest_running; struct arm_v7s_io_pgtable { struct io_pgtable iop; arm_v7s_iopte *pgd; struct kmem_cache *l2_tables; spinlock_t split_lock; }; static dma_addr_t __arm_v7s_dma_addr(void *pages) { return (dma_addr_t)virt_to_phys(pages); } static arm_v7s_iopte *iopte_deref(arm_v7s_iopte pte, int lvl) { if (ARM_V7S_PTE_IS_TABLE(pte, lvl)) pte &= ARM_V7S_TABLE_MASK; else pte &= ARM_V7S_LVL_MASK(lvl); return phys_to_virt(pte); } static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp, struct arm_v7s_io_pgtable *data) { struct io_pgtable_cfg *cfg = &data->iop.cfg; struct device *dev = cfg->iommu_dev; dma_addr_t dma; size_t size = ARM_V7S_TABLE_SIZE(lvl); void *table = NULL; if (lvl == 1) table = (void *)__get_dma_pages(__GFP_ZERO, get_order(size)); else if (lvl == 2) table = kmem_cache_zalloc(data->l2_tables, gfp | GFP_DMA); if (table && !(cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA)) { dma = dma_map_single(dev, table, 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(table)) goto out_unmap; } kmemleak_ignore(table); return table; 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: if (lvl == 1) free_pages((unsigned long)table, get_order(size)); else kmem_cache_free(data->l2_tables, table); return NULL; } static void __arm_v7s_free_table(void *table, int lvl, struct arm_v7s_io_pgtable *data) { struct io_pgtable_cfg *cfg = &data->iop.cfg; struct device *dev = cfg->iommu_dev; size_t size = ARM_V7S_TABLE_SIZE(lvl); if (!(cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA)) dma_unmap_single(dev, __arm_v7s_dma_addr(table), size, DMA_TO_DEVICE); if (lvl == 1) free_pages((unsigned long)table, get_order(size)); else kmem_cache_free(data->l2_tables, table); } static void __arm_v7s_pte_sync(arm_v7s_iopte *ptep, int num_entries, struct io_pgtable_cfg *cfg) { if (cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA) return; dma_sync_single_for_device(cfg->iommu_dev, __arm_v7s_dma_addr(ptep), num_entries * sizeof(*ptep), DMA_TO_DEVICE); } static void __arm_v7s_set_pte(arm_v7s_iopte *ptep, arm_v7s_iopte pte, int num_entries, struct io_pgtable_cfg *cfg) { int i; for (i = 0; i < num_entries; i++) ptep[i] = pte; __arm_v7s_pte_sync(ptep, num_entries, cfg); } static arm_v7s_iopte arm_v7s_prot_to_pte(int prot, int lvl, struct io_pgtable_cfg *cfg) { bool ap = !(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS); arm_v7s_iopte pte = ARM_V7S_ATTR_NG | ARM_V7S_ATTR_S; if (!(prot & IOMMU_MMIO)) pte |= ARM_V7S_ATTR_TEX(1); if (ap) { pte |= ARM_V7S_PTE_AF; if (!(prot & IOMMU_PRIV)) pte |= ARM_V7S_PTE_AP_UNPRIV; if (!(prot & IOMMU_WRITE)) pte |= ARM_V7S_PTE_AP_RDONLY; } pte <<= ARM_V7S_ATTR_SHIFT(lvl); if ((prot & IOMMU_NOEXEC) && ap) pte |= ARM_V7S_ATTR_XN(lvl); if (prot & IOMMU_MMIO) pte |= ARM_V7S_ATTR_B; else if (prot & IOMMU_CACHE) pte |= ARM_V7S_ATTR_B | ARM_V7S_ATTR_C; pte |= ARM_V7S_PTE_TYPE_PAGE; if (lvl == 1 && (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)) pte |= ARM_V7S_ATTR_NS_SECTION; if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB) pte |= ARM_V7S_ATTR_MTK_4GB; return pte; } static int arm_v7s_pte_to_prot(arm_v7s_iopte pte, int lvl) { int prot = IOMMU_READ; arm_v7s_iopte attr = pte >> ARM_V7S_ATTR_SHIFT(lvl); if (!(attr & ARM_V7S_PTE_AP_RDONLY)) prot |= IOMMU_WRITE; if (!(attr & ARM_V7S_PTE_AP_UNPRIV)) prot |= IOMMU_PRIV; if ((attr & (ARM_V7S_TEX_MASK << ARM_V7S_TEX_SHIFT)) == 0) prot |= IOMMU_MMIO; else if (pte & ARM_V7S_ATTR_C) prot |= IOMMU_CACHE; if (pte & ARM_V7S_ATTR_XN(lvl)) prot |= IOMMU_NOEXEC; return prot; } static arm_v7s_iopte arm_v7s_pte_to_cont(arm_v7s_iopte pte, int lvl) { if (lvl == 1) { pte |= ARM_V7S_CONT_SECTION; } else if (lvl == 2) { arm_v7s_iopte xn = pte & ARM_V7S_ATTR_XN(lvl); arm_v7s_iopte tex = pte & ARM_V7S_CONT_PAGE_TEX_MASK; pte ^= xn | tex | ARM_V7S_PTE_TYPE_PAGE; pte |= (xn << ARM_V7S_CONT_PAGE_XN_SHIFT) | (tex << ARM_V7S_CONT_PAGE_TEX_SHIFT) | ARM_V7S_PTE_TYPE_CONT_PAGE; } return pte; } static arm_v7s_iopte arm_v7s_cont_to_pte(arm_v7s_iopte pte, int lvl) { if (lvl == 1) { pte &= ~ARM_V7S_CONT_SECTION; } else if (lvl == 2) { arm_v7s_iopte xn = pte & BIT(ARM_V7S_CONT_PAGE_XN_SHIFT); arm_v7s_iopte tex = pte & (ARM_V7S_CONT_PAGE_TEX_MASK << ARM_V7S_CONT_PAGE_TEX_SHIFT); pte ^= xn | tex | ARM_V7S_PTE_TYPE_CONT_PAGE; pte |= (xn >> ARM_V7S_CONT_PAGE_XN_SHIFT) | (tex >> ARM_V7S_CONT_PAGE_TEX_SHIFT) | ARM_V7S_PTE_TYPE_PAGE; } return pte; } static bool arm_v7s_pte_is_cont(arm_v7s_iopte pte, int lvl) { if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte, lvl)) return pte & ARM_V7S_CONT_SECTION; else if (lvl == 2) return !(pte & ARM_V7S_PTE_TYPE_PAGE); return false; } static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *, unsigned long, size_t, int, arm_v7s_iopte *); static int arm_v7s_init_pte(struct arm_v7s_io_pgtable *data, unsigned long iova, phys_addr_t paddr, int prot, int lvl, int num_entries, arm_v7s_iopte *ptep) { struct io_pgtable_cfg *cfg = &data->iop.cfg; arm_v7s_iopte pte; int i; for (i = 0; i < num_entries; i++) if (ARM_V7S_PTE_IS_TABLE(ptep[i], lvl)) { /* * We need to unmap and free the old table before * overwriting it with a block entry. */ arm_v7s_iopte *tblp; size_t sz = ARM_V7S_BLOCK_SIZE(lvl); tblp = ptep - ARM_V7S_LVL_IDX(iova, lvl); if (WARN_ON(__arm_v7s_unmap(data, iova + i * sz, sz, lvl, tblp) != sz)) return -EINVAL; } else if (ptep[i]) { /* We require an unmap first */ WARN_ON(!selftest_running); return -EEXIST; } pte = arm_v7s_prot_to_pte(prot, lvl, cfg); if (num_entries > 1) pte = arm_v7s_pte_to_cont(pte, lvl); pte |= paddr & ARM_V7S_LVL_MASK(lvl); __arm_v7s_set_pte(ptep, pte, num_entries, cfg); return 0; } static arm_v7s_iopte arm_v7s_install_table(arm_v7s_iopte *table, arm_v7s_iopte *ptep, arm_v7s_iopte curr, struct io_pgtable_cfg *cfg) { arm_v7s_iopte old, new; new = virt_to_phys(table) | ARM_V7S_PTE_TYPE_TABLE; if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS) new |= ARM_V7S_ATTR_NS_TABLE; /* * Ensure the table itself is visible before its PTE can be. * Whilst we could get away with cmpxchg64_release below, this * doesn't have any ordering semantics when !CONFIG_SMP. */ dma_wmb(); old = cmpxchg_relaxed(ptep, curr, new); __arm_v7s_pte_sync(ptep, 1, cfg); return old; } static int __arm_v7s_map(struct arm_v7s_io_pgtable *data, unsigned long iova, phys_addr_t paddr, size_t size, int prot, int lvl, arm_v7s_iopte *ptep) { struct io_pgtable_cfg *cfg = &data->iop.cfg; arm_v7s_iopte pte, *cptep; int num_entries = size >> ARM_V7S_LVL_SHIFT(lvl); /* Find our entry at the current level */ ptep += ARM_V7S_LVL_IDX(iova, lvl); /* If we can install a leaf entry at this level, then do so */ if (num_entries) return arm_v7s_init_pte(data, iova, paddr, prot, lvl, num_entries, ptep); /* We can't allocate tables at the final level */ if (WARN_ON(lvl == 2)) return -EINVAL; /* Grab a pointer to the next level */ pte = READ_ONCE(*ptep); if (!pte) { cptep = __arm_v7s_alloc_table(lvl + 1, GFP_ATOMIC, data); if (!cptep) return -ENOMEM; pte = arm_v7s_install_table(cptep, ptep, 0, cfg); if (pte) __arm_v7s_free_table(cptep, lvl + 1, data); } else { /* We've no easy way of knowing if it's synced yet, so... */ __arm_v7s_pte_sync(ptep, 1, cfg); } if (ARM_V7S_PTE_IS_TABLE(pte, lvl)) { cptep = iopte_deref(pte, lvl); } else if (pte) { /* We require an unmap first */ WARN_ON(!selftest_running); return -EEXIST; } /* Rinse, repeat */ return __arm_v7s_map(data, iova, paddr, size, prot, lvl + 1, cptep); } static int arm_v7s_map(struct io_pgtable_ops *ops, unsigned long iova, phys_addr_t paddr, size_t size, int prot) { struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops); struct io_pgtable *iop = &data->iop; int ret; /* If no access, then nothing to do */ if (!(prot & (IOMMU_READ | IOMMU_WRITE))) return 0; if (WARN_ON(upper_32_bits(iova) || upper_32_bits(paddr))) return -ERANGE; ret = __arm_v7s_map(data, iova, paddr, size, prot, 1, data->pgd); /* * 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. */ if (iop->cfg.quirks & IO_PGTABLE_QUIRK_TLBI_ON_MAP) { io_pgtable_tlb_add_flush(iop, iova, size, ARM_V7S_BLOCK_SIZE(2), false); io_pgtable_tlb_sync(iop); } else { wmb(); } return ret; } static void arm_v7s_free_pgtable(struct io_pgtable *iop) { struct arm_v7s_io_pgtable *data = io_pgtable_to_data(iop); int i; for (i = 0; i < ARM_V7S_PTES_PER_LVL(1); i++) { arm_v7s_iopte pte = data->pgd[i]; if (ARM_V7S_PTE_IS_TABLE(pte, 1)) __arm_v7s_free_table(iopte_deref(pte, 1), 2, data); } __arm_v7s_free_table(data->pgd, 1, data); kmem_cache_destroy(data->l2_tables); kfree(data); } static arm_v7s_iopte arm_v7s_split_cont(struct arm_v7s_io_pgtable *data, unsigned long iova, int idx, int lvl, arm_v7s_iopte *ptep) { struct io_pgtable *iop = &data->iop; arm_v7s_iopte pte; size_t size = ARM_V7S_BLOCK_SIZE(lvl); int i; /* Check that we didn't lose a race to get the lock */ pte = *ptep; if (!arm_v7s_pte_is_cont(pte, lvl)) return pte; ptep -= idx & (ARM_V7S_CONT_PAGES - 1); pte = arm_v7s_cont_to_pte(pte, lvl); for (i = 0; i < ARM_V7S_CONT_PAGES; i++) ptep[i] = pte + i * size; __arm_v7s_pte_sync(ptep, ARM_V7S_CONT_PAGES, &iop->cfg); size *= ARM_V7S_CONT_PAGES; io_pgtable_tlb_add_flush(iop, iova, size, size, true); io_pgtable_tlb_sync(iop); return pte; } static size_t arm_v7s_split_blk_unmap(struct arm_v7s_io_pgtable *data, unsigned long iova, size_t size, arm_v7s_iopte blk_pte, arm_v7s_iopte *ptep) { struct io_pgtable_cfg *cfg = &data->iop.cfg; arm_v7s_iopte pte, *tablep; int i, unmap_idx, num_entries, num_ptes; tablep = __arm_v7s_alloc_table(2, GFP_ATOMIC, data); if (!tablep) return 0; /* Bytes unmapped */ num_ptes = ARM_V7S_PTES_PER_LVL(2); num_entries = size >> ARM_V7S_LVL_SHIFT(2); unmap_idx = ARM_V7S_LVL_IDX(iova, 2); pte = arm_v7s_prot_to_pte(arm_v7s_pte_to_prot(blk_pte, 1), 2, cfg); if (num_entries > 1) pte = arm_v7s_pte_to_cont(pte, 2); for (i = 0; i < num_ptes; i += num_entries, pte += size) { /* Unmap! */ if (i == unmap_idx) continue; __arm_v7s_set_pte(&tablep[i], pte, num_entries, cfg); } pte = arm_v7s_install_table(tablep, ptep, blk_pte, cfg); if (pte != blk_pte) { __arm_v7s_free_table(tablep, 2, data); if (!ARM_V7S_PTE_IS_TABLE(pte, 1)) return 0; tablep = iopte_deref(pte, 1); return __arm_v7s_unmap(data, iova, size, 2, tablep); } io_pgtable_tlb_add_flush(&data->iop, iova, size, size, true); return size; } static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *data, unsigned long iova, size_t size, int lvl, arm_v7s_iopte *ptep) { arm_v7s_iopte pte[ARM_V7S_CONT_PAGES]; struct io_pgtable *iop = &data->iop; int idx, i = 0, num_entries = size >> ARM_V7S_LVL_SHIFT(lvl); /* Something went horribly wrong and we ran out of page table */ if (WARN_ON(lvl > 2)) return 0; idx = ARM_V7S_LVL_IDX(iova, lvl); ptep += idx; do { pte[i] = READ_ONCE(ptep[i]); if (WARN_ON(!ARM_V7S_PTE_IS_VALID(pte[i]))) return 0; } while (++i < num_entries); /* * If we've hit a contiguous 'large page' entry at this level, it * needs splitting first, unless we're unmapping the whole lot. * * For splitting, we can't rewrite 16 PTEs atomically, and since we * can't necessarily assume TEX remap we don't have a software bit to * mark live entries being split. In practice (i.e. DMA API code), we * will never be splitting large pages anyway, so just wrap this edge * case in a lock for the sake of correctness and be done with it. */ if (num_entries <= 1 && arm_v7s_pte_is_cont(pte[0], lvl)) { unsigned long flags; spin_lock_irqsave(&data->split_lock, flags); pte[0] = arm_v7s_split_cont(data, iova, idx, lvl, ptep); spin_unlock_irqrestore(&data->split_lock, flags); } /* If the size matches this level, we're in the right place */ if (num_entries) { size_t blk_size = ARM_V7S_BLOCK_SIZE(lvl); __arm_v7s_set_pte(ptep, 0, num_entries, &iop->cfg); for (i = 0; i < num_entries; i++) { if (ARM_V7S_PTE_IS_TABLE(pte[i], lvl)) { /* Also flush any partial walks */ io_pgtable_tlb_add_flush(iop, iova, blk_size, ARM_V7S_BLOCK_SIZE(lvl + 1), false); io_pgtable_tlb_sync(iop); ptep = iopte_deref(pte[i], lvl); __arm_v7s_free_table(ptep, lvl + 1, data); } else { io_pgtable_tlb_add_flush(iop, iova, blk_size, blk_size, true); } iova += blk_size; } return size; } else if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte[0], lvl)) { /* * Insert a table at the next level to map the old region, * minus the part we want to unmap */ return arm_v7s_split_blk_unmap(data, iova, size, pte[0], ptep); } /* Keep on walkin' */ ptep = iopte_deref(pte[0], lvl); return __arm_v7s_unmap(data, iova, size, lvl + 1, ptep); } static size_t arm_v7s_unmap(struct io_pgtable_ops *ops, unsigned long iova, size_t size) { struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops); if (WARN_ON(upper_32_bits(iova))) return 0; return __arm_v7s_unmap(data, iova, size, 1, data->pgd); } static phys_addr_t arm_v7s_iova_to_phys(struct io_pgtable_ops *ops, unsigned long iova) { struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops); arm_v7s_iopte *ptep = data->pgd, pte; int lvl = 0; u32 mask; do { ptep += ARM_V7S_LVL_IDX(iova, ++lvl); pte = READ_ONCE(*ptep); ptep = iopte_deref(pte, lvl); } while (ARM_V7S_PTE_IS_TABLE(pte, lvl)); if (!ARM_V7S_PTE_IS_VALID(pte)) return 0; mask = ARM_V7S_LVL_MASK(lvl); if (arm_v7s_pte_is_cont(pte, lvl)) mask *= ARM_V7S_CONT_PAGES; return (pte & mask) | (iova & ~mask); } static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie) { struct arm_v7s_io_pgtable *data; #ifdef PHYS_OFFSET if (upper_32_bits(PHYS_OFFSET)) return NULL; #endif if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS) return NULL; if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS | IO_PGTABLE_QUIRK_NO_PERMS | IO_PGTABLE_QUIRK_TLBI_ON_MAP | IO_PGTABLE_QUIRK_ARM_MTK_4GB | IO_PGTABLE_QUIRK_NO_DMA)) return NULL; /* If ARM_MTK_4GB is enabled, the NO_PERMS is also expected. */ if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB && !(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS)) return NULL; data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data) return NULL; spin_lock_init(&data->split_lock); data->l2_tables = kmem_cache_create("io-pgtable_armv7s_l2", ARM_V7S_TABLE_SIZE(2), ARM_V7S_TABLE_SIZE(2), SLAB_CACHE_DMA, NULL); if (!data->l2_tables) goto out_free_data; data->iop.ops = (struct io_pgtable_ops) { .map = arm_v7s_map, .unmap = arm_v7s_unmap, .iova_to_phys = arm_v7s_iova_to_phys, }; /* We have to do this early for __arm_v7s_alloc_table to work... */ data->iop.cfg = *cfg; /* * Unless the IOMMU driver indicates supersection support by * having SZ_16M set in the initial bitmap, they won't be used. */ cfg->pgsize_bitmap &= SZ_4K | SZ_64K | SZ_1M | SZ_16M; /* TCR: T0SZ=0, disable TTBR1 */ cfg->arm_v7s_cfg.tcr = ARM_V7S_TCR_PD1; /* * TEX remap: the indices used map to the closest equivalent types * under the non-TEX-remap interpretation of those attribute bits, * excepting various implementation-defined aspects of shareability. */ cfg->arm_v7s_cfg.prrr = ARM_V7S_PRRR_TR(1, ARM_V7S_PRRR_TYPE_DEVICE) | ARM_V7S_PRRR_TR(4, ARM_V7S_PRRR_TYPE_NORMAL) | ARM_V7S_PRRR_TR(7, ARM_V7S_PRRR_TYPE_NORMAL) | ARM_V7S_PRRR_DS0 | ARM_V7S_PRRR_DS1 | ARM_V7S_PRRR_NS1 | ARM_V7S_PRRR_NOS(7); cfg->arm_v7s_cfg.nmrr = ARM_V7S_NMRR_IR(7, ARM_V7S_RGN_WBWA) | ARM_V7S_NMRR_OR(7, ARM_V7S_RGN_WBWA); /* Looking good; allocate a pgd */ data->pgd = __arm_v7s_alloc_table(1, GFP_KERNEL, data); if (!data->pgd) goto out_free_data; /* Ensure the empty pgd is visible before any actual TTBR write */ wmb(); /* TTBRs */ cfg->arm_v7s_cfg.ttbr[0] = virt_to_phys(data->pgd) | ARM_V7S_TTBR_S | ARM_V7S_TTBR_NOS | ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_WBWA) | ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_WBWA); cfg->arm_v7s_cfg.ttbr[1] = 0; return &data->iop; out_free_data: kmem_cache_destroy(data->l2_tables); kfree(data); return NULL; } struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns = { .alloc = arm_v7s_alloc_pgtable, .free = arm_v7s_free_pgtable, }; #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S_SELFTEST static struct io_pgtable_cfg *cfg_cookie; static void dummy_tlb_flush_all(void *cookie) { WARN_ON(cookie != cfg_cookie); } static void dummy_tlb_add_flush(unsigned long iova, size_t size, size_t granule, bool leaf, void *cookie) { WARN_ON(cookie != cfg_cookie); WARN_ON(!(size & cfg_cookie->pgsize_bitmap)); } static void dummy_tlb_sync(void *cookie) { WARN_ON(cookie != cfg_cookie); } static const struct iommu_gather_ops dummy_tlb_ops = { .tlb_flush_all = dummy_tlb_flush_all, .tlb_add_flush = dummy_tlb_add_flush, .tlb_sync = dummy_tlb_sync, }; #define __FAIL(ops) ({ \ WARN(1, "selftest: test failed\n"); \ selftest_running = false; \ -EFAULT; \ }) static int __init arm_v7s_do_selftests(void) { struct io_pgtable_ops *ops; struct io_pgtable_cfg cfg = { .tlb = &dummy_tlb_ops, .oas = 32, .ias = 32, .quirks = IO_PGTABLE_QUIRK_ARM_NS | IO_PGTABLE_QUIRK_NO_DMA, .pgsize_bitmap = SZ_4K | SZ_64K | SZ_1M | SZ_16M, }; unsigned int iova, size, iova_start; unsigned int i, loopnr = 0; selftest_running = true; cfg_cookie = &cfg; ops = alloc_io_pgtable_ops(ARM_V7S, &cfg, &cfg); if (!ops) { pr_err("selftest: failed to allocate io pgtable ops\n"); return -EINVAL; } /* * Initial sanity checks. * Empty page tables shouldn't provide any translations. */ if (ops->iova_to_phys(ops, 42)) return __FAIL(ops); if (ops->iova_to_phys(ops, SZ_1G + 42)) return __FAIL(ops); if (ops->iova_to_phys(ops, SZ_2G + 42)) return __FAIL(ops); /* * Distinct mappings of different granule sizes. */ iova = 0; for_each_set_bit(i, &cfg.pgsize_bitmap, BITS_PER_LONG) { size = 1UL << i; if (ops->map(ops, iova, iova, size, IOMMU_READ | IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_CACHE)) return __FAIL(ops); /* Overlapping mappings */ if (!ops->map(ops, iova, iova + size, size, IOMMU_READ | IOMMU_NOEXEC)) return __FAIL(ops); if (ops->iova_to_phys(ops, iova + 42) != (iova + 42)) return __FAIL(ops); iova += SZ_16M; loopnr++; } /* Partial unmap */ i = 1; size = 1UL << __ffs(cfg.pgsize_bitmap); while (i < loopnr) { iova_start = i * SZ_16M; if (ops->unmap(ops, iova_start + size, size) != size) return __FAIL(ops); /* Remap of partial unmap */ if (ops->map(ops, iova_start + size, size, size, IOMMU_READ)) return __FAIL(ops); if (ops->iova_to_phys(ops, iova_start + size + 42) != (size + 42)) return __FAIL(ops); i++; } /* Full unmap */ iova = 0; for_each_set_bit(i, &cfg.pgsize_bitmap, BITS_PER_LONG) { size = 1UL << i; if (ops->unmap(ops, iova, size) != size) return __FAIL(ops); if (ops->iova_to_phys(ops, iova + 42)) return __FAIL(ops); /* Remap full block */ if (ops->map(ops, iova, iova, size, IOMMU_WRITE)) return __FAIL(ops); if (ops->iova_to_phys(ops, iova + 42) != (iova + 42)) return __FAIL(ops); iova += SZ_16M; } free_io_pgtable_ops(ops); selftest_running = false; pr_info("self test ok\n"); return 0; } subsys_initcall(arm_v7s_do_selftests); #endif