// SPDX-License-Identifier: GPL-2.0-only
/*
* CPU-agnostic ARM page table allocator.
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#define pr_fmt(fmt) "arm-lpae io-pgtable: " fmt
#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/io-pgtable.h>
#include <linux/kernel.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <asm/barrier.h>
#define ARM_LPAE_MAX_ADDR_BITS 52
#define ARM_LPAE_S2_MAX_CONCAT_PAGES 16
#define ARM_LPAE_MAX_LEVELS 4
/* Struct accessors */
#define io_pgtable_to_data(x) \
container_of((x), struct arm_lpae_io_pgtable, iop)
#define io_pgtable_ops_to_data(x) \
io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
/*
* For consistency with the architecture, we always consider
* ARM_LPAE_MAX_LEVELS levels, with the walk starting at level n >=0
*/
#define ARM_LPAE_START_LVL(d) (ARM_LPAE_MAX_LEVELS - (d)->levels)
/*
* Calculate the right shift amount to get to the portion describing level l
* in a virtual address mapped by the pagetable in d.
*/
#define ARM_LPAE_LVL_SHIFT(l,d) \
((((d)->levels - ((l) - ARM_LPAE_START_LVL(d) + 1)) \
* (d)->bits_per_level) + (d)->pg_shift)
#define ARM_LPAE_GRANULE(d) (1UL << (d)->pg_shift)
#define ARM_LPAE_PAGES_PER_PGD(d) \
DIV_ROUND_UP((d)->pgd_size, ARM_LPAE_GRANULE(d))
/*
* Calculate the index at level l used to map virtual address a using the
* pagetable in d.
*/
#define ARM_LPAE_PGD_IDX(l,d) \
((l) == ARM_LPAE_START_LVL(d) ? ilog2(ARM_LPAE_PAGES_PER_PGD(d)) : 0)
#define ARM_LPAE_LVL_IDX(a,l,d) \
(((u64)(a) >> ARM_LPAE_LVL_SHIFT(l,d)) & \
((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1))
/* Calculate the block/page mapping size at level l for pagetable in d. */
#define ARM_LPAE_BLOCK_SIZE(l,d) \
(1ULL << (ilog2(sizeof(arm_lpae_iopte)) + \
((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level)))
/* Page table bits */
#define ARM_LPAE_PTE_TYPE_SHIFT 0
#define ARM_LPAE_PTE_TYPE_MASK 0x3
#define ARM_LPAE_PTE_TYPE_BLOCK 1
#define ARM_LPAE_PTE_TYPE_TABLE 3
#define ARM_LPAE_PTE_TYPE_PAGE 3
#define ARM_LPAE_PTE_ADDR_MASK GENMASK_ULL(47,12)
#define ARM_LPAE_PTE_NSTABLE (((arm_lpae_iopte)1) << 63)
#define ARM_LPAE_PTE_XN (((arm_lpae_iopte)3) << 53)
#define ARM_LPAE_PTE_AF (((arm_lpae_iopte)1) << 10)
#define ARM_LPAE_PTE_SH_NS (((arm_lpae_iopte)0) << 8)
#define ARM_LPAE_PTE_SH_OS (((arm_lpae_iopte)2) << 8)
#define ARM_LPAE_PTE_SH_IS (((arm_lpae_iopte)3) << 8)
#define ARM_LPAE_PTE_NS (((arm_lpae_iopte)1) << 5)
#define ARM_LPAE_PTE_VALID (((arm_lpae_iopte)1) << 0)
#define ARM_LPAE_PTE_ATTR_LO_MASK (((arm_lpae_iopte)0x3ff) << 2)
/* Ignore the contiguous bit for block splitting */
#define ARM_LPAE_PTE_ATTR_HI_MASK (((arm_lpae_iopte)6) << 52)
#define ARM_LPAE_PTE_ATTR_MASK (ARM_LPAE_PTE_ATTR_LO_MASK | \
ARM_LPAE_PTE_ATTR_HI_MASK)
/* Software bit for solving coherency races */
#define ARM_LPAE_PTE_SW_SYNC (((arm_lpae_iopte)1) << 55)
/* Stage-1 PTE */
#define ARM_LPAE_PTE_AP_UNPRIV (((arm_lpae_iopte)1) << 6)
#define ARM_LPAE_PTE_AP_RDONLY (((arm_lpae_iopte)2) << 6)
#define ARM_LPAE_PTE_ATTRINDX_SHIFT 2
#define ARM_LPAE_PTE_nG (((arm_lpae_iopte)1) << 11)
/* Stage-2 PTE */
#define ARM_LPAE_PTE_HAP_FAULT (((arm_lpae_iopte)0) << 6)
#define ARM_LPAE_PTE_HAP_READ (((arm_lpae_iopte)1) << 6)
#define ARM_LPAE_PTE_HAP_WRITE (((arm_lpae_iopte)2) << 6)
#define ARM_LPAE_PTE_MEMATTR_OIWB (((arm_lpae_iopte)0xf) << 2)
#define ARM_LPAE_PTE_MEMATTR_NC (((arm_lpae_iopte)0x5) << 2)
#define ARM_LPAE_PTE_MEMATTR_DEV (((arm_lpae_iopte)0x1) << 2)
/* Register bits */
#define ARM_32_LPAE_TCR_EAE (1 << 31)
#define ARM_64_LPAE_S2_TCR_RES1 (1 << 31)
#define ARM_LPAE_TCR_EPD1 (1 << 23)
#define ARM_LPAE_TCR_TG0_4K (0 << 14)
#define ARM_LPAE_TCR_TG0_64K (1 << 14)
#define ARM_LPAE_TCR_TG0_16K (2 << 14)
#define ARM_LPAE_TCR_SH0_SHIFT 12
#define ARM_LPAE_TCR_SH0_MASK 0x3
#define ARM_LPAE_TCR_SH_NS 0
#define ARM_LPAE_TCR_SH_OS 2
#define ARM_LPAE_TCR_SH_IS 3
#define ARM_LPAE_TCR_ORGN0_SHIFT 10
#define ARM_LPAE_TCR_IRGN0_SHIFT 8
#define ARM_LPAE_TCR_RGN_MASK 0x3
#define ARM_LPAE_TCR_RGN_NC 0
#define ARM_LPAE_TCR_RGN_WBWA 1
#define ARM_LPAE_TCR_RGN_WT 2
#define ARM_LPAE_TCR_RGN_WB 3
#define ARM_LPAE_TCR_SL0_SHIFT 6
#define ARM_LPAE_TCR_SL0_MASK 0x3
#define ARM_LPAE_TCR_T0SZ_SHIFT 0
#define ARM_LPAE_TCR_SZ_MASK 0xf
#define ARM_LPAE_TCR_PS_SHIFT 16
#define ARM_LPAE_TCR_PS_MASK 0x7
#define ARM_LPAE_TCR_IPS_SHIFT 32
#define ARM_LPAE_TCR_IPS_MASK 0x7
#define ARM_LPAE_TCR_PS_32_BIT 0x0ULL
#define ARM_LPAE_TCR_PS_36_BIT 0x1ULL
#define ARM_LPAE_TCR_PS_40_BIT 0x2ULL
#define ARM_LPAE_TCR_PS_42_BIT 0x3ULL
#define ARM_LPAE_TCR_PS_44_BIT 0x4ULL
#define ARM_LPAE_TCR_PS_48_BIT 0x5ULL
#define ARM_LPAE_TCR_PS_52_BIT 0x6ULL
#define ARM_LPAE_MAIR_ATTR_SHIFT(n) ((n) << 3)
#define ARM_LPAE_MAIR_ATTR_MASK 0xff
#define ARM_LPAE_MAIR_ATTR_DEVICE 0x04
#define ARM_LPAE_MAIR_ATTR_NC 0x44
#define ARM_LPAE_MAIR_ATTR_INC_OWBRWA 0xf4
#define ARM_LPAE_MAIR_ATTR_WBRWA 0xff
#define ARM_LPAE_MAIR_ATTR_IDX_NC 0
#define ARM_LPAE_MAIR_ATTR_IDX_CACHE 1
#define ARM_LPAE_MAIR_ATTR_IDX_DEV 2
#define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE 3
#define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
#define ARM_MALI_LPAE_TTBR_READ_INNER BIT(2)
#define ARM_MALI_LPAE_TTBR_SHARE_OUTER BIT(4)
#define ARM_MALI_LPAE_MEMATTR_IMP_DEF 0x88ULL
#define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
/* IOPTE accessors */
#define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
#define iopte_type(pte,l) \
(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
#define iopte_prot(pte) ((pte) & ARM_LPAE_PTE_ATTR_MASK)
struct arm_lpae_io_pgtable {
struct io_pgtable iop;
int levels;
size_t pgd_size;
unsigned long pg_shift;
unsigned long bits_per_level;
void *pgd;
};
typedef u64 arm_lpae_iopte;
static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
enum io_pgtable_fmt fmt)
{
if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_PAGE;
return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_BLOCK;
}
static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
struct arm_lpae_io_pgtable *data)
{
arm_lpae_iopte pte = paddr;
/* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */
return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK;
}
static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
struct arm_lpae_io_pgtable *data)
{
u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
if (data->pg_shift < 16)
return paddr;
/* Rotate the packed high-order bits back to the top */
return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4);
}
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;
int order = get_order(size);
struct page *p;
dma_addr_t dma;
void *pages;
VM_BUG_ON((gfp & __GFP_HIGHMEM));
p = alloc_pages_node(dev ? dev_to_node(dev) : NUMA_NO_NODE,
gfp | __GFP_ZERO, order);
if (!p)
return NULL;
pages = page_address(p);
if (!cfg->coherent_walk) {
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(p, order);
return NULL;
}
static void __arm_lpae_free_pages(void *pages, size_t size,
struct io_pgtable_cfg *cfg)
{
if (!cfg->coherent_walk)
dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages),
size, DMA_TO_DEVICE);
free_pages((unsigned long)pages, get_order(size));
}
static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep,
struct io_pgtable_cfg *cfg)
{
dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
sizeof(*ptep), DMA_TO_DEVICE);
}
static void __arm_lpae_set_pte(arm_lpae_iopte *ptep, arm_lpae_iopte pte,
struct io_pgtable_cfg *cfg)
{
*ptep = pte;
if (!cfg->coherent_walk)
__arm_lpae_sync_pte(ptep, cfg);
}
static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
struct iommu_iotlb_gather *gather,
unsigned long iova, size_t size, int lvl,
arm_lpae_iopte *ptep);
static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
phys_addr_t paddr, arm_lpae_iopte prot,
int lvl, arm_lpae_iopte *ptep)
{
arm_lpae_iopte pte = prot;
if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
pte |= ARM_LPAE_PTE_NS;
if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
pte |= ARM_LPAE_PTE_TYPE_PAGE;
else
pte |= ARM_LPAE_PTE_TYPE_BLOCK;
if (data->iop.fmt != ARM_MALI_LPAE)
pte |= ARM_LPAE_PTE_AF;
pte |= ARM_LPAE_PTE_SH_IS;
pte |= paddr_to_iopte(paddr, data);
__arm_lpae_set_pte(ptep, pte, &data->iop.cfg);
}
static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
unsigned long iova, phys_addr_t paddr,
arm_lpae_iopte prot, int lvl,
arm_lpae_iopte *ptep)
{
arm_lpae_iopte pte = *ptep;
if (iopte_leaf(pte, lvl, data->iop.fmt)) {
/* We require an unmap first */
WARN_ON(!selftest_running);
return -EEXIST;
} else if (iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_TABLE) {
/*
* We need to unmap and free the old table before
* overwriting it with a block entry.
*/
arm_lpae_iopte *tblp;
size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
if (__arm_lpae_unmap(data, NULL, iova, sz, lvl, tblp) != sz) {
WARN_ON(1);
return -EINVAL;
}
}
__arm_lpae_init_pte(data, paddr, prot, lvl, ptep);
return 0;
}
static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
arm_lpae_iopte *ptep,
arm_lpae_iopte curr,
struct io_pgtable_cfg *cfg)
{
arm_lpae_iopte old, new;
new = __pa(table) | ARM_LPAE_PTE_TYPE_TABLE;
if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
new |= ARM_LPAE_PTE_NSTABLE;
/*
* 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 = cmpxchg64_relaxed(ptep, curr, new);
if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC))
return old;
/* Even if it's not ours, there's no point waiting; just kick it */
__arm_lpae_sync_pte(ptep, cfg);
if (old == curr)
WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC);
return old;
}
static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
phys_addr_t paddr, size_t size, arm_lpae_iopte prot,
int lvl, arm_lpae_iopte *ptep)
{
arm_lpae_iopte *cptep, pte;
size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
size_t tblsz = ARM_LPAE_GRANULE(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 & cfg->pgsize_bitmap))
return arm_lpae_init_pte(data, iova, paddr, prot, lvl, ptep);
/* We can't allocate tables at the final level */
if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
return -EINVAL;
/* Grab a pointer to the next level */
pte = READ_ONCE(*ptep);
if (!pte) {
cptep = __arm_lpae_alloc_pages(tblsz, GFP_ATOMIC, cfg);
if (!cptep)
return -ENOMEM;
pte = arm_lpae_install_table(cptep, ptep, 0, cfg);
if (pte)
__arm_lpae_free_pages(cptep, tblsz, cfg);
} else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) {
__arm_lpae_sync_pte(ptep, cfg);
}
if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
cptep = iopte_deref(pte, data);
} else if (pte) {
/* We require an unmap first */
WARN_ON(!selftest_running);
return -EEXIST;
}
/* Rinse, repeat */
return __arm_lpae_map(data, iova, paddr, size, prot, lvl + 1, cptep);
}
static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
int prot)
{
arm_lpae_iopte pte;
if (data->iop.fmt == ARM_64_LPAE_S1 ||
data->iop.fmt == ARM_32_LPAE_S1) {
pte = ARM_LPAE_PTE_nG;
if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
pte |= ARM_LPAE_PTE_AP_RDONLY;
if (!(prot & IOMMU_PRIV))
pte |= ARM_LPAE_PTE_AP_UNPRIV;
} else {
pte = ARM_LPAE_PTE_HAP_FAULT;
if (prot & IOMMU_READ)
pte |= ARM_LPAE_PTE_HAP_READ;
if (prot & IOMMU_WRITE)
pte |= ARM_LPAE_PTE_HAP_WRITE;
}
/*
* Note that this logic is structured to accommodate Mali LPAE
* having stage-1-like attributes but stage-2-like permissions.
*/
if (data->iop.fmt == ARM_64_LPAE_S2 ||
data->iop.fmt == ARM_32_LPAE_S2) {
if (prot & IOMMU_MMIO)
pte |= ARM_LPAE_PTE_MEMATTR_DEV;
else if (prot & IOMMU_CACHE)
pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
else
pte |= ARM_LPAE_PTE_MEMATTR_NC;
} else {
if (prot & IOMMU_MMIO)
pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
else if (prot & IOMMU_CACHE)
pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
else if (prot & IOMMU_QCOM_SYS_CACHE)
pte |= (ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE
<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
}
if (prot & IOMMU_NOEXEC)
pte |= ARM_LPAE_PTE_XN;
return pte;
}
static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
phys_addr_t paddr, size_t size, int iommu_prot)
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
arm_lpae_iopte *ptep = data->pgd;
int ret, lvl = ARM_LPAE_START_LVL(data);
arm_lpae_iopte prot;
/* If no access, then nothing to do */
if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
return 0;
if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias) ||
paddr >= (1ULL << data->iop.cfg.oas)))
return -ERANGE;
prot = arm_lpae_prot_to_pte(data, iommu_prot);
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,
arm_lpae_iopte *ptep)
{
arm_lpae_iopte *start, *end;
unsigned long table_size;
if (lvl == ARM_LPAE_START_LVL(data))
table_size = data->pgd_size;
else
table_size = ARM_LPAE_GRANULE(data);
start = ptep;
/* 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++;
if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
continue;
__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
}
__arm_lpae_free_pages(start, table_size, &data->iop.cfg);
}
static void arm_lpae_free_pgtable(struct io_pgtable *iop)
{
struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
__arm_lpae_free_pgtable(data, ARM_LPAE_START_LVL(data), data->pgd);
kfree(data);
}
static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
struct iommu_iotlb_gather *gather,
unsigned long iova, size_t size,
arm_lpae_iopte blk_pte, int lvl,
arm_lpae_iopte *ptep)
{
struct io_pgtable_cfg *cfg = &data->iop.cfg;
arm_lpae_iopte pte, *tablep;
phys_addr_t blk_paddr;
size_t tablesz = ARM_LPAE_GRANULE(data);
size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
int i, unmap_idx = -1;
if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
return 0;
tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg);
if (!tablep)
return 0; /* Bytes unmapped */
if (size == split_sz)
unmap_idx = ARM_LPAE_LVL_IDX(iova, lvl, data);
blk_paddr = iopte_to_paddr(blk_pte, data);
pte = iopte_prot(blk_pte);
for (i = 0; i < tablesz / sizeof(pte); i++, blk_paddr += split_sz) {
/* Unmap! */
if (i == unmap_idx)
continue;
__arm_lpae_init_pte(data, blk_paddr, pte, lvl, &tablep[i]);
}
pte = arm_lpae_install_table(tablep, ptep, blk_pte, cfg);
if (pte != blk_pte) {
__arm_lpae_free_pages(tablep, tablesz, cfg);
/*
* We may race against someone unmapping another part of this
* block, but anything else is invalid. We can't misinterpret
* a page entry here since we're never at the last level.
*/
if (iopte_type(pte, lvl - 1) != ARM_LPAE_PTE_TYPE_TABLE)
return 0;
tablep = iopte_deref(pte, data);
} else if (unmap_idx >= 0) {
io_pgtable_tlb_add_page(&data->iop, gather, iova, size);
return size;
}
return __arm_lpae_unmap(data, gather, iova, size, lvl, tablep);
}
static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
struct iommu_iotlb_gather *gather,
unsigned long iova, size_t size, int lvl,
arm_lpae_iopte *ptep)
{
arm_lpae_iopte pte;
struct io_pgtable *iop = &data->iop;
/* Something went horribly wrong and we ran out of page table */
if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
return 0;
ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
pte = READ_ONCE(*ptep);
if (WARN_ON(!pte))
return 0;
/* If the size matches this level, we're in the right place */
if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
__arm_lpae_set_pte(ptep, 0, &iop->cfg);
if (!iopte_leaf(pte, lvl, iop->fmt)) {
/* Also flush any partial walks */
io_pgtable_tlb_flush_walk(iop, iova, size,
ARM_LPAE_GRANULE(data));
ptep = iopte_deref(pte, data);
__arm_lpae_free_pgtable(data, lvl + 1, ptep);
} else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) {
/*
* Order the PTE update against queueing the IOVA, to
* guarantee that a flush callback from a different CPU
* has observed it before the TLBIALL can be issued.
*/
smp_wmb();
} else {
io_pgtable_tlb_add_page(iop, gather, iova, size);
}
return size;
} else if (iopte_leaf(pte, lvl, iop->fmt)) {
/*
* Insert a table at the next level to map the old region,
* minus the part we want to unmap
*/
return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
lvl + 1, ptep);
}
/* Keep on walkin' */
ptep = iopte_deref(pte, data);
return __arm_lpae_unmap(data, gather, iova, size, lvl + 1, ptep);
}
static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
size_t size, struct iommu_iotlb_gather *gather)
{
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);
if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias)))
return 0;
return __arm_lpae_unmap(data, gather, iova, size, lvl, ptep);
}
static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
unsigned long iova)
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
arm_lpae_iopte pte, *ptep = data->pgd;
int lvl = ARM_LPAE_START_LVL(data);
do {
/* Valid IOPTE pointer? */
if (!ptep)
return 0;
/* Grab the IOPTE we're interested in */
ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
pte = READ_ONCE(*ptep);
/* Valid entry? */
if (!pte)
return 0;
/* Leaf entry? */
if (iopte_leaf(pte, lvl, data->iop.fmt))
goto found_translation;
/* Take it to the next level */
ptep = iopte_deref(pte, data);
} while (++lvl < ARM_LPAE_MAX_LEVELS);
/* Ran out of page tables to walk */
return 0;
found_translation:
iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
return iopte_to_paddr(pte, data) | iova;
}
static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
{
unsigned long granule, page_sizes;
unsigned int max_addr_bits = 48;
/*
* We need to restrict the supported page sizes to match the
* translation regime for a particular granule. Aim to match
* the CPU page size if possible, otherwise prefer smaller sizes.
* While we're at it, restrict the block sizes to match the
* chosen granule.
*/
if (cfg->pgsize_bitmap & PAGE_SIZE)
granule = PAGE_SIZE;
else if (cfg->pgsize_bitmap & ~PAGE_MASK)
granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK);
else if (cfg->pgsize_bitmap & PAGE_MASK)
granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK);
else
granule = 0;
switch (granule) {
case SZ_4K:
page_sizes = (SZ_4K | SZ_2M | SZ_1G);
break;
case SZ_16K:
page_sizes = (SZ_16K | SZ_32M);
break;
case SZ_64K:
max_addr_bits = 52;
page_sizes = (SZ_64K | SZ_512M);
if (cfg->oas > 48)
page_sizes |= 1ULL << 42; /* 4TB */
break;
default:
page_sizes = 0;
}
cfg->pgsize_bitmap &= page_sizes;
cfg->ias = min(cfg->ias, max_addr_bits);
cfg->oas = min(cfg->oas, max_addr_bits);
}
static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
{
unsigned long va_bits, pgd_bits;
struct arm_lpae_io_pgtable *data;
arm_lpae_restrict_pgsizes(cfg);
if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K)))
return NULL;
if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS)
return NULL;
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;
data->pg_shift = __ffs(cfg->pgsize_bitmap);
data->bits_per_level = data->pg_shift - ilog2(sizeof(arm_lpae_iopte));
va_bits = cfg->ias - data->pg_shift;
data->levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
/* Calculate the actual size of our pgd (without concatenation) */
pgd_bits = va_bits - (data->bits_per_level * (data->levels - 1));
data->pgd_size = 1UL << (pgd_bits + ilog2(sizeof(arm_lpae_iopte)));
data->iop.ops = (struct io_pgtable_ops) {
.map = arm_lpae_map,
.unmap = arm_lpae_unmap,
.iova_to_phys = arm_lpae_iova_to_phys,
};
return data;
}
static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
{
u64 reg;
struct arm_lpae_io_pgtable *data;
if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
IO_PGTABLE_QUIRK_NON_STRICT))
return NULL;
data = arm_lpae_alloc_pgtable(cfg);
if (!data)
return NULL;
/* TCR */
if (cfg->coherent_walk) {
reg = (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
(ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
(ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
} else {
reg = (ARM_LPAE_TCR_SH_OS << ARM_LPAE_TCR_SH0_SHIFT) |
(ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_IRGN0_SHIFT) |
(ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_ORGN0_SHIFT);
}
switch (ARM_LPAE_GRANULE(data)) {
case SZ_4K:
reg |= ARM_LPAE_TCR_TG0_4K;
break;
case SZ_16K:
reg |= ARM_LPAE_TCR_TG0_16K;
break;
case SZ_64K:
reg |= ARM_LPAE_TCR_TG0_64K;
break;
}
switch (cfg->oas) {
case 32:
reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 36:
reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 40:
reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 42:
reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 44:
reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 48:
reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
case 52:
reg |= (ARM_LPAE_TCR_PS_52_BIT << ARM_LPAE_TCR_IPS_SHIFT);
break;
default:
goto out_free_data;
}
reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
/* Disable speculative walks through TTBR1 */
reg |= ARM_LPAE_TCR_EPD1;
cfg->arm_lpae_s1_cfg.tcr = reg;
/* MAIRs */
reg = (ARM_LPAE_MAIR_ATTR_NC
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
(ARM_LPAE_MAIR_ATTR_WBRWA
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
(ARM_LPAE_MAIR_ATTR_DEVICE
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) |
(ARM_LPAE_MAIR_ATTR_INC_OWBRWA
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE));
cfg->arm_lpae_s1_cfg.mair[0] = reg;
cfg->arm_lpae_s1_cfg.mair[1] = 0;
/* Looking good; allocate a pgd */
data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg);
if (!data->pgd)
goto out_free_data;
/* 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);
cfg->arm_lpae_s1_cfg.ttbr[1] = 0;
return &data->iop;
out_free_data:
kfree(data);
return NULL;
}
static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
{
u64 reg, sl;
struct arm_lpae_io_pgtable *data;
/* The NS quirk doesn't apply at stage 2 */
if (cfg->quirks & ~(IO_PGTABLE_QUIRK_NON_STRICT))
return NULL;
data = arm_lpae_alloc_pgtable(cfg);
if (!data)
return NULL;
/*
* Concatenate PGDs at level 1 if possible in order to reduce
* the depth of the stage-2 walk.
*/
if (data->levels == ARM_LPAE_MAX_LEVELS) {
unsigned long pgd_pages;
pgd_pages = data->pgd_size >> ilog2(sizeof(arm_lpae_iopte));
if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
data->pgd_size = pgd_pages << data->pg_shift;
data->levels--;
}
}
/* VTCR */
reg = ARM_64_LPAE_S2_TCR_RES1 |
(ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
(ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
(ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
sl = ARM_LPAE_START_LVL(data);
switch (ARM_LPAE_GRANULE(data)) {
case SZ_4K:
reg |= ARM_LPAE_TCR_TG0_4K;
sl++; /* SL0 format is different for 4K granule size */
break;
case SZ_16K:
reg |= ARM_LPAE_TCR_TG0_16K;
break;
case SZ_64K:
reg |= ARM_LPAE_TCR_TG0_64K;
break;
}
switch (cfg->oas) {
case 32:
reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 36:
reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 40:
reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 42:
reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 44:
reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 48:
reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
case 52:
reg |= (ARM_LPAE_TCR_PS_52_BIT << ARM_LPAE_TCR_PS_SHIFT);
break;
default:
goto out_free_data;
}
reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
reg |= (~sl & ARM_LPAE_TCR_SL0_MASK) << ARM_LPAE_TCR_SL0_SHIFT;
cfg->arm_lpae_s2_cfg.vtcr = reg;
/* Allocate pgd pages */
data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg);
if (!data->pgd)
goto out_free_data;
/* Ensure the empty pgd is visible before any actual TTBR write */
wmb();
/* VTTBR */
cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
return &data->iop;
out_free_data:
kfree(data);
return NULL;
}
static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
{
struct io_pgtable *iop;
if (cfg->ias > 32 || cfg->oas > 40)
return NULL;
cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
iop = arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
if (iop) {
cfg->arm_lpae_s1_cfg.tcr |= ARM_32_LPAE_TCR_EAE;
cfg->arm_lpae_s1_cfg.tcr &= 0xffffffff;
}
return iop;
}
static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
{
struct io_pgtable *iop;
if (cfg->ias > 40 || cfg->oas > 40)
return NULL;
cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
iop = arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
if (iop)
cfg->arm_lpae_s2_cfg.vtcr &= 0xffffffff;
return iop;
}
static struct io_pgtable *
arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
{
struct arm_lpae_io_pgtable *data;
/* No quirks for Mali (hopefully) */
if (cfg->quirks)
return NULL;
if (cfg->ias > 48 || cfg->oas > 40)
return NULL;
cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
data = arm_lpae_alloc_pgtable(cfg);
if (!data)
return NULL;
/* Mali seems to need a full 4-level table regardless of IAS */
if (data->levels < ARM_LPAE_MAX_LEVELS) {
data->levels = ARM_LPAE_MAX_LEVELS;
data->pgd_size = sizeof(arm_lpae_iopte);
}
/*
* MEMATTR: Mali has no actual notion of a non-cacheable type, so the
* best we can do is mimic the out-of-tree driver and hope that the
* "implementation-defined caching policy" is good enough. Similarly,
* we'll use it for the sake of a valid attribute for our 'device'
* index, although callers should never request that in practice.
*/
cfg->arm_mali_lpae_cfg.memattr =
(ARM_MALI_LPAE_MEMATTR_IMP_DEF
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
(ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
(ARM_MALI_LPAE_MEMATTR_IMP_DEF
<< ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV));
data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg);
if (!data->pgd)
goto out_free_data;
/* Ensure the empty pgd is visible before TRANSTAB can be written */
wmb();
cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) |
ARM_MALI_LPAE_TTBR_READ_INNER |
ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
return &data->iop;
out_free_data:
kfree(data);
return NULL;
}
struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
.alloc = arm_64_lpae_alloc_pgtable_s1,
.free = arm_lpae_free_pgtable,
};
struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = {
.alloc = arm_64_lpae_alloc_pgtable_s2,
.free = arm_lpae_free_pgtable,
};
struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = {
.alloc = arm_32_lpae_alloc_pgtable_s1,
.free = arm_lpae_free_pgtable,
};
struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
.alloc = arm_32_lpae_alloc_pgtable_s2,
.free = arm_lpae_free_pgtable,
};
struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
.alloc = arm_mali_lpae_alloc_pgtable,
.free = arm_lpae_free_pgtable,
};
#ifdef [31mCONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST[0m
static struct io_pgtable_cfg *cfg_cookie;
static void dummy_tlb_flush_all(void *cookie)
{
WARN_ON(cookie != cfg_cookie);
}
static void dummy_tlb_flush(unsigned long iova, size_t size, size_t granule,
void *cookie)
{
WARN_ON(cookie != cfg_cookie);
WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
}
static void dummy_tlb_add_page(struct iommu_iotlb_gather *gather,
unsigned long iova, size_t granule, void *cookie)
{
dummy_tlb_flush(iova, granule, granule, cookie);
}
static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
.tlb_flush_all = dummy_tlb_flush_all,
.tlb_flush_walk = dummy_tlb_flush,
.tlb_flush_leaf = dummy_tlb_flush,
.tlb_add_page = dummy_tlb_add_page,
};
static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops)
{
struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
struct io_pgtable_cfg *cfg = &data->iop.cfg;
pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
cfg->pgsize_bitmap, cfg->ias);
pr_err("data: %d levels, 0x%zx pgd_size, %lu pg_shift, %lu bits_per_level, pgd @ %p\n",
data->levels, data->pgd_size, data->pg_shift,
data->bits_per_level, data->pgd);
}
#define __FAIL(ops, i) ({ \
WARN(1, "selftest: test failed for fmt idx %d\n", (i)); \
arm_lpae_dump_ops(ops); \
selftest_running = false; \
-EFAULT; \
})
static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
{
static const enum io_pgtable_fmt fmts[] = {
ARM_64_LPAE_S1,
ARM_64_LPAE_S2,
};
int i, j;
unsigned long iova;
size_t size;
struct io_pgtable_ops *ops;
selftest_running = true;
for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
cfg_cookie = cfg;
ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
if (!ops) {
pr_err("selftest: failed to allocate io pgtable ops\n");
return -ENOMEM;
}
/*
* Initial sanity checks.
* Empty page tables shouldn't provide any translations.
*/
if (ops->iova_to_phys(ops, 42))
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, SZ_1G + 42))
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, SZ_2G + 42))
return __FAIL(ops, i);
/*
* Distinct mappings of different granule sizes.
*/
iova = 0;
for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
size = 1UL << j;
if (ops->map(ops, iova, iova, size, IOMMU_READ |
IOMMU_WRITE |
IOMMU_NOEXEC |
IOMMU_CACHE))
return __FAIL(ops, i);
/* Overlapping mappings */
if (!ops->map(ops, iova, iova + size, size,
IOMMU_READ | IOMMU_NOEXEC))
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
return __FAIL(ops, i);
iova += SZ_1G;
}
/* Partial unmap */
size = 1UL << __ffs(cfg->pgsize_bitmap);
if (ops->unmap(ops, SZ_1G + size, size, NULL) != size)
return __FAIL(ops, i);
/* Remap of partial unmap */
if (ops->map(ops, SZ_1G + size, size, size, IOMMU_READ))
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
return __FAIL(ops, i);
/* Full unmap */
iova = 0;
for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
size = 1UL << j;
if (ops->unmap(ops, iova, size, NULL) != size)
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, iova + 42))
return __FAIL(ops, i);
/* Remap full block */
if (ops->map(ops, iova, iova, size, IOMMU_WRITE))
return __FAIL(ops, i);
if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
return __FAIL(ops, i);
iova += SZ_1G;
}
free_io_pgtable_ops(ops);
}
selftest_running = false;
return 0;
}
static int __init arm_lpae_do_selftests(void)
{
static const unsigned long pgsize[] = {
SZ_4K | SZ_2M | SZ_1G,
SZ_16K | SZ_32M,
SZ_64K | SZ_512M,
};
static const unsigned int ias[] = {
32, 36, 40, 42, 44, 48,
};
int i, j, pass = 0, fail = 0;
struct io_pgtable_cfg cfg = {
.tlb = &dummy_tlb_ops,
.oas = 48,
.coherent_walk = true,
};
for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
for (j = 0; j < ARRAY_SIZE(ias); ++j) {
cfg.pgsize_bitmap = pgsize[i];
cfg.ias = ias[j];
pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
pgsize[i], ias[j]);
if (arm_lpae_run_tests(&cfg))
fail++;
else
pass++;
}
}
pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
return fail ? -EFAULT : 0;
}
subsys_initcall(arm_lpae_do_selftests);
#endif