| /* |
| * Generic page table allocator for IOMMUs. |
| * |
| * 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 ARM Limited |
| * |
| * Author: Will Deacon <will.deacon@arm.com> |
| */ |
| |
| #define pr_fmt(fmt) "io-pgtable: " fmt |
| |
| #include <linux/bug.h> |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/iommu.h> |
| #include <linux/debugfs.h> |
| #include <linux/atomic.h> |
| #include <linux/module.h> |
| |
| #include "io-pgtable.h" |
| |
| static const struct io_pgtable_init_fns * |
| io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = { |
| #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE |
| [ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns, |
| [ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns, |
| [ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns, |
| [ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns, |
| #endif |
| #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S |
| [ARM_V7S] = &io_pgtable_arm_v7s_init_fns, |
| #endif |
| #ifdef CONFIG_IOMMU_IO_PGTABLE_FAST |
| [ARM_V8L_FAST] = &io_pgtable_av8l_fast_init_fns, |
| #endif |
| }; |
| |
| static struct dentry *io_pgtable_top; |
| |
| struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt, |
| struct io_pgtable_cfg *cfg, |
| void *cookie) |
| { |
| struct io_pgtable *iop; |
| const struct io_pgtable_init_fns *fns; |
| |
| if (fmt >= IO_PGTABLE_NUM_FMTS) |
| return NULL; |
| |
| fns = io_pgtable_init_table[fmt]; |
| if (!fns) |
| return NULL; |
| |
| iop = fns->alloc(cfg, cookie); |
| if (!iop) |
| return NULL; |
| |
| iop->fmt = fmt; |
| iop->cookie = cookie; |
| iop->cfg = *cfg; |
| |
| return &iop->ops; |
| } |
| |
| /* |
| * It is the IOMMU driver's responsibility to ensure that the page table |
| * is no longer accessible to the walker by this point. |
| */ |
| void free_io_pgtable_ops(struct io_pgtable_ops *ops) |
| { |
| struct io_pgtable *iop; |
| |
| if (!ops) |
| return; |
| |
| iop = container_of(ops, struct io_pgtable, ops); |
| io_pgtable_tlb_flush_all(iop); |
| io_pgtable_init_table[iop->fmt]->free(iop); |
| } |
| |
| static atomic_t pages_allocated; |
| |
| void *io_pgtable_alloc_pages_exact(struct io_pgtable_cfg *cfg, void *cookie, |
| size_t size, gfp_t gfp_mask) |
| { |
| void *ret; |
| |
| if (cfg->tlb->alloc_pages_exact) |
| ret = cfg->tlb->alloc_pages_exact(cookie, size, gfp_mask); |
| else |
| ret = alloc_pages_exact(size, gfp_mask); |
| |
| if (likely(ret)) |
| atomic_add(1 << get_order(size), &pages_allocated); |
| |
| return ret; |
| } |
| |
| void io_pgtable_free_pages_exact(struct io_pgtable_cfg *cfg, void *cookie, |
| void *virt, size_t size) |
| { |
| if (cfg->tlb->free_pages_exact) |
| cfg->tlb->free_pages_exact(cookie, virt, size); |
| else |
| free_pages_exact(virt, size); |
| |
| atomic_sub(1 << get_order(size), &pages_allocated); |
| } |
| |
| static int io_pgtable_init(void) |
| { |
| io_pgtable_top = debugfs_create_dir("io-pgtable", iommu_debugfs_top); |
| |
| if (!io_pgtable_top) |
| return -ENODEV; |
| |
| if (!debugfs_create_atomic_t("pages", 0600, |
| io_pgtable_top, &pages_allocated)) { |
| debugfs_remove_recursive(io_pgtable_top); |
| return -ENODEV; |
| } |
| |
| return 0; |
| } |
| |
| static void io_pgtable_exit(void) |
| { |
| debugfs_remove_recursive(io_pgtable_top); |
| } |
| |
| module_init(io_pgtable_init); |
| module_exit(io_pgtable_exit); |