diff options
Diffstat (limited to 'drivers/iommu/amd/io_pgtable.c')
| -rw-r--r-- | drivers/iommu/amd/io_pgtable.c | 577 |
1 files changed, 0 insertions, 577 deletions
diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c deleted file mode 100644 index 70c2f5b1631b..000000000000 --- a/drivers/iommu/amd/io_pgtable.c +++ /dev/null @@ -1,577 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * CPU-agnostic AMD IO page table allocator. - * - * Copyright (C) 2020 Advanced Micro Devices, Inc. - * Author: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> - */ - -#define pr_fmt(fmt) "AMD-Vi: " fmt -#define dev_fmt(fmt) pr_fmt(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 <linux/seqlock.h> - -#include <asm/barrier.h> - -#include "amd_iommu_types.h" -#include "amd_iommu.h" -#include "../iommu-pages.h" - -/* - * Helper function to get the first pte of a large mapping - */ -static u64 *first_pte_l7(u64 *pte, unsigned long *page_size, - unsigned long *count) -{ - unsigned long pte_mask, pg_size, cnt; - u64 *fpte; - - pg_size = PTE_PAGE_SIZE(*pte); - cnt = PAGE_SIZE_PTE_COUNT(pg_size); - pte_mask = ~((cnt << 3) - 1); - fpte = (u64 *)(((unsigned long)pte) & pte_mask); - - if (page_size) - *page_size = pg_size; - - if (count) - *count = cnt; - - return fpte; -} - -static void free_pt_lvl(u64 *pt, struct iommu_pages_list *freelist, int lvl) -{ - u64 *p; - int i; - - for (i = 0; i < 512; ++i) { - /* PTE present? */ - if (!IOMMU_PTE_PRESENT(pt[i])) - continue; - - /* Large PTE? */ - if (PM_PTE_LEVEL(pt[i]) == 0 || - PM_PTE_LEVEL(pt[i]) == 7) - continue; - - /* - * Free the next level. No need to look at l1 tables here since - * they can only contain leaf PTEs; just free them directly. - */ - p = IOMMU_PTE_PAGE(pt[i]); - if (lvl > 2) - free_pt_lvl(p, freelist, lvl - 1); - else - iommu_pages_list_add(freelist, p); - } - - iommu_pages_list_add(freelist, pt); -} - -static void free_sub_pt(u64 *root, int mode, struct iommu_pages_list *freelist) -{ - switch (mode) { - case PAGE_MODE_NONE: - case PAGE_MODE_7_LEVEL: - break; - case PAGE_MODE_1_LEVEL: - iommu_pages_list_add(freelist, root); - break; - case PAGE_MODE_2_LEVEL: - case PAGE_MODE_3_LEVEL: - case PAGE_MODE_4_LEVEL: - case PAGE_MODE_5_LEVEL: - case PAGE_MODE_6_LEVEL: - free_pt_lvl(root, freelist, mode); - break; - default: - BUG(); - } -} - -/* - * This function is used to add another level to an IO page table. Adding - * another level increases the size of the address space by 9 bits to a size up - * to 64 bits. - */ -static bool increase_address_space(struct amd_io_pgtable *pgtable, - unsigned long address, - unsigned int page_size_level, - gfp_t gfp) -{ - struct io_pgtable_cfg *cfg = &pgtable->pgtbl.cfg; - struct protection_domain *domain = - container_of(pgtable, struct protection_domain, iop); - unsigned long flags; - bool ret = true; - u64 *pte; - - pte = iommu_alloc_pages_node_sz(cfg->amd.nid, gfp, SZ_4K); - if (!pte) - return false; - - spin_lock_irqsave(&domain->lock, flags); - - if (address <= PM_LEVEL_SIZE(pgtable->mode) && - pgtable->mode - 1 >= page_size_level) - goto out; - - ret = false; - if (WARN_ON_ONCE(pgtable->mode == amd_iommu_hpt_level)) - goto out; - - *pte = PM_LEVEL_PDE(pgtable->mode, iommu_virt_to_phys(pgtable->root)); - - write_seqcount_begin(&pgtable->seqcount); - pgtable->root = pte; - pgtable->mode += 1; - write_seqcount_end(&pgtable->seqcount); - - amd_iommu_update_and_flush_device_table(domain); - - pte = NULL; - ret = true; - -out: - spin_unlock_irqrestore(&domain->lock, flags); - iommu_free_pages(pte); - - return ret; -} - -static u64 *alloc_pte(struct amd_io_pgtable *pgtable, - unsigned long address, - unsigned long page_size, - u64 **pte_page, - gfp_t gfp, - bool *updated) -{ - unsigned long last_addr = address + (page_size - 1); - struct io_pgtable_cfg *cfg = &pgtable->pgtbl.cfg; - unsigned int seqcount; - int level, end_lvl; - u64 *pte, *page; - - BUG_ON(!is_power_of_2(page_size)); - - while (last_addr > PM_LEVEL_SIZE(pgtable->mode) || - pgtable->mode - 1 < PAGE_SIZE_LEVEL(page_size)) { - /* - * Return an error if there is no memory to update the - * page-table. - */ - if (!increase_address_space(pgtable, last_addr, - PAGE_SIZE_LEVEL(page_size), gfp)) - return NULL; - } - - - do { - seqcount = read_seqcount_begin(&pgtable->seqcount); - - level = pgtable->mode - 1; - pte = &pgtable->root[PM_LEVEL_INDEX(level, address)]; - } while (read_seqcount_retry(&pgtable->seqcount, seqcount)); - - - address = PAGE_SIZE_ALIGN(address, page_size); - end_lvl = PAGE_SIZE_LEVEL(page_size); - - while (level > end_lvl) { - u64 __pte, __npte; - int pte_level; - - __pte = *pte; - pte_level = PM_PTE_LEVEL(__pte); - - /* - * If we replace a series of large PTEs, we need - * to tear down all of them. - */ - if (IOMMU_PTE_PRESENT(__pte) && - pte_level == PAGE_MODE_7_LEVEL) { - unsigned long count, i; - u64 *lpte; - - lpte = first_pte_l7(pte, NULL, &count); - - /* - * Unmap the replicated PTEs that still match the - * original large mapping - */ - for (i = 0; i < count; ++i) - cmpxchg64(&lpte[i], __pte, 0ULL); - - *updated = true; - continue; - } - - if (!IOMMU_PTE_PRESENT(__pte) || - pte_level == PAGE_MODE_NONE) { - page = iommu_alloc_pages_node_sz(cfg->amd.nid, gfp, - SZ_4K); - - if (!page) - return NULL; - - __npte = PM_LEVEL_PDE(level, iommu_virt_to_phys(page)); - - /* pte could have been changed somewhere. */ - if (!try_cmpxchg64(pte, &__pte, __npte)) - iommu_free_pages(page); - else if (IOMMU_PTE_PRESENT(__pte)) - *updated = true; - - continue; - } - - /* No level skipping support yet */ - if (pte_level != level) - return NULL; - - level -= 1; - - pte = IOMMU_PTE_PAGE(__pte); - - if (pte_page && level == end_lvl) - *pte_page = pte; - - pte = &pte[PM_LEVEL_INDEX(level, address)]; - } - - return pte; -} - -/* - * This function checks if there is a PTE for a given dma address. If - * there is one, it returns the pointer to it. - */ -static u64 *fetch_pte(struct amd_io_pgtable *pgtable, - unsigned long address, - unsigned long *page_size) -{ - int level; - unsigned int seqcount; - u64 *pte; - - *page_size = 0; - - if (address > PM_LEVEL_SIZE(pgtable->mode)) - return NULL; - - do { - seqcount = read_seqcount_begin(&pgtable->seqcount); - level = pgtable->mode - 1; - pte = &pgtable->root[PM_LEVEL_INDEX(level, address)]; - } while (read_seqcount_retry(&pgtable->seqcount, seqcount)); - - *page_size = PTE_LEVEL_PAGE_SIZE(level); - - while (level > 0) { - - /* Not Present */ - if (!IOMMU_PTE_PRESENT(*pte)) - return NULL; - - /* Large PTE */ - if (PM_PTE_LEVEL(*pte) == PAGE_MODE_7_LEVEL || - PM_PTE_LEVEL(*pte) == PAGE_MODE_NONE) - break; - - /* No level skipping support yet */ - if (PM_PTE_LEVEL(*pte) != level) - return NULL; - - level -= 1; - - /* Walk to the next level */ - pte = IOMMU_PTE_PAGE(*pte); - pte = &pte[PM_LEVEL_INDEX(level, address)]; - *page_size = PTE_LEVEL_PAGE_SIZE(level); - } - - /* - * If we have a series of large PTEs, make - * sure to return a pointer to the first one. - */ - if (PM_PTE_LEVEL(*pte) == PAGE_MODE_7_LEVEL) - pte = first_pte_l7(pte, page_size, NULL); - - return pte; -} - -static void free_clear_pte(u64 *pte, u64 pteval, - struct iommu_pages_list *freelist) -{ - u64 *pt; - int mode; - - while (!try_cmpxchg64(pte, &pteval, 0)) - pr_warn("AMD-Vi: IOMMU pte changed since we read it\n"); - - if (!IOMMU_PTE_PRESENT(pteval)) - return; - - pt = IOMMU_PTE_PAGE(pteval); - mode = IOMMU_PTE_MODE(pteval); - - free_sub_pt(pt, mode, freelist); -} - -/* - * Generic mapping functions. It maps a physical address into a DMA - * address space. It allocates the page table pages if necessary. - * In the future it can be extended to a generic mapping function - * supporting all features of AMD IOMMU page tables like level skipping - * and full 64 bit address spaces. - */ -static int iommu_v1_map_pages(struct io_pgtable_ops *ops, unsigned long iova, - phys_addr_t paddr, size_t pgsize, size_t pgcount, - int prot, gfp_t gfp, size_t *mapped) -{ - struct amd_io_pgtable *pgtable = io_pgtable_ops_to_data(ops); - struct iommu_pages_list freelist = IOMMU_PAGES_LIST_INIT(freelist); - bool updated = false; - u64 __pte, *pte; - int ret, i, count; - size_t size = pgcount << __ffs(pgsize); - unsigned long o_iova = iova; - - BUG_ON(!IS_ALIGNED(iova, pgsize)); - BUG_ON(!IS_ALIGNED(paddr, pgsize)); - - ret = -EINVAL; - if (!(prot & IOMMU_PROT_MASK)) - goto out; - - while (pgcount > 0) { - count = PAGE_SIZE_PTE_COUNT(pgsize); - pte = alloc_pte(pgtable, iova, pgsize, NULL, gfp, &updated); - - ret = -ENOMEM; - if (!pte) - goto out; - - for (i = 0; i < count; ++i) - free_clear_pte(&pte[i], pte[i], &freelist); - - if (!iommu_pages_list_empty(&freelist)) - updated = true; - - if (count > 1) { - __pte = PAGE_SIZE_PTE(__sme_set(paddr), pgsize); - __pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_PR | IOMMU_PTE_FC; - } else - __pte = __sme_set(paddr) | IOMMU_PTE_PR | IOMMU_PTE_FC; - - if (prot & IOMMU_PROT_IR) - __pte |= IOMMU_PTE_IR; - if (prot & IOMMU_PROT_IW) - __pte |= IOMMU_PTE_IW; - - for (i = 0; i < count; ++i) - pte[i] = __pte; - - iova += pgsize; - paddr += pgsize; - pgcount--; - if (mapped) - *mapped += pgsize; - } - - ret = 0; - -out: - if (updated) { - struct protection_domain *dom = io_pgtable_ops_to_domain(ops); - unsigned long flags; - - spin_lock_irqsave(&dom->lock, flags); - /* - * Flush domain TLB(s) and wait for completion. Any Device-Table - * Updates and flushing already happened in - * increase_address_space(). - */ - amd_iommu_domain_flush_pages(dom, o_iova, size); - spin_unlock_irqrestore(&dom->lock, flags); - } - - /* Everything flushed out, free pages now */ - iommu_put_pages_list(&freelist); - - return ret; -} - -static unsigned long iommu_v1_unmap_pages(struct io_pgtable_ops *ops, - unsigned long iova, - size_t pgsize, size_t pgcount, - struct iommu_iotlb_gather *gather) -{ - struct amd_io_pgtable *pgtable = io_pgtable_ops_to_data(ops); - unsigned long long unmapped; - unsigned long unmap_size; - u64 *pte; - size_t size = pgcount << __ffs(pgsize); - - BUG_ON(!is_power_of_2(pgsize)); - - unmapped = 0; - - while (unmapped < size) { - pte = fetch_pte(pgtable, iova, &unmap_size); - if (pte) { - int i, count; - - count = PAGE_SIZE_PTE_COUNT(unmap_size); - for (i = 0; i < count; i++) - pte[i] = 0ULL; - } else { - return unmapped; - } - - iova = (iova & ~(unmap_size - 1)) + unmap_size; - unmapped += unmap_size; - } - - return unmapped; -} - -static phys_addr_t iommu_v1_iova_to_phys(struct io_pgtable_ops *ops, unsigned long iova) -{ - struct amd_io_pgtable *pgtable = io_pgtable_ops_to_data(ops); - unsigned long offset_mask, pte_pgsize; - u64 *pte, __pte; - - pte = fetch_pte(pgtable, iova, &pte_pgsize); - - if (!pte || !IOMMU_PTE_PRESENT(*pte)) - return 0; - - offset_mask = pte_pgsize - 1; - __pte = __sme_clr(*pte & PM_ADDR_MASK); - - return (__pte & ~offset_mask) | (iova & offset_mask); -} - -static bool pte_test_and_clear_dirty(u64 *ptep, unsigned long size, - unsigned long flags) -{ - bool test_only = flags & IOMMU_DIRTY_NO_CLEAR; - bool dirty = false; - int i, count; - - /* - * 2.2.3.2 Host Dirty Support - * When a non-default page size is used , software must OR the - * Dirty bits in all of the replicated host PTEs used to map - * the page. The IOMMU does not guarantee the Dirty bits are - * set in all of the replicated PTEs. Any portion of the page - * may have been written even if the Dirty bit is set in only - * one of the replicated PTEs. - */ - count = PAGE_SIZE_PTE_COUNT(size); - for (i = 0; i < count && test_only; i++) { - if (test_bit(IOMMU_PTE_HD_BIT, (unsigned long *)&ptep[i])) { - dirty = true; - break; - } - } - - for (i = 0; i < count && !test_only; i++) { - if (test_and_clear_bit(IOMMU_PTE_HD_BIT, - (unsigned long *)&ptep[i])) { - dirty = true; - } - } - - return dirty; -} - -static int iommu_v1_read_and_clear_dirty(struct io_pgtable_ops *ops, - unsigned long iova, size_t size, - unsigned long flags, - struct iommu_dirty_bitmap *dirty) -{ - struct amd_io_pgtable *pgtable = io_pgtable_ops_to_data(ops); - unsigned long end = iova + size - 1; - - do { - unsigned long pgsize = 0; - u64 *ptep, pte; - - ptep = fetch_pte(pgtable, iova, &pgsize); - if (ptep) - pte = READ_ONCE(*ptep); - if (!ptep || !IOMMU_PTE_PRESENT(pte)) { - pgsize = pgsize ?: PTE_LEVEL_PAGE_SIZE(0); - iova += pgsize; - continue; - } - - /* - * Mark the whole IOVA range as dirty even if only one of - * the replicated PTEs were marked dirty. - */ - if (pte_test_and_clear_dirty(ptep, pgsize, flags)) - iommu_dirty_bitmap_record(dirty, iova, pgsize); - iova += pgsize; - } while (iova < end); - - return 0; -} - -/* - * ---------------------------------------------------- - */ -static void v1_free_pgtable(struct io_pgtable *iop) -{ - struct amd_io_pgtable *pgtable = container_of(iop, struct amd_io_pgtable, pgtbl); - struct iommu_pages_list freelist = IOMMU_PAGES_LIST_INIT(freelist); - - if (pgtable->mode == PAGE_MODE_NONE) - return; - - /* Page-table is not visible to IOMMU anymore, so free it */ - BUG_ON(pgtable->mode < PAGE_MODE_NONE || - pgtable->mode > amd_iommu_hpt_level); - - free_sub_pt(pgtable->root, pgtable->mode, &freelist); - iommu_put_pages_list(&freelist); -} - -static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie) -{ - struct amd_io_pgtable *pgtable = io_pgtable_cfg_to_data(cfg); - - pgtable->root = - iommu_alloc_pages_node_sz(cfg->amd.nid, GFP_KERNEL, SZ_4K); - if (!pgtable->root) - return NULL; - pgtable->mode = PAGE_MODE_3_LEVEL; - seqcount_init(&pgtable->seqcount); - - cfg->pgsize_bitmap = amd_iommu_pgsize_bitmap; - cfg->ias = IOMMU_IN_ADDR_BIT_SIZE; - cfg->oas = IOMMU_OUT_ADDR_BIT_SIZE; - - pgtable->pgtbl.ops.map_pages = iommu_v1_map_pages; - pgtable->pgtbl.ops.unmap_pages = iommu_v1_unmap_pages; - pgtable->pgtbl.ops.iova_to_phys = iommu_v1_iova_to_phys; - pgtable->pgtbl.ops.read_and_clear_dirty = iommu_v1_read_and_clear_dirty; - - return &pgtable->pgtbl; -} - -struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns = { - .alloc = v1_alloc_pgtable, - .free = v1_free_pgtable, -}; |