1 /* 2 * Generic page table allocator for IOMMUs. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 * 16 * Copyright (C) 2014 ARM Limited 17 * 18 * Author: Will Deacon <will.deacon@arm.com> 19 */ 20 21 #include <linux/bug.h> 22 #include <linux/kernel.h> 23 #include <linux/types.h> 24 25 #include "io-pgtable.h" 26 27 static const struct io_pgtable_init_fns * 28 io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = 29 { 30 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE 31 [ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns, 32 [ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns, 33 [ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns, 34 [ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns, 35 #endif 36 }; 37 38 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt, 39 struct io_pgtable_cfg *cfg, 40 void *cookie) 41 { 42 struct io_pgtable *iop; 43 const struct io_pgtable_init_fns *fns; 44 45 if (fmt >= IO_PGTABLE_NUM_FMTS) 46 return NULL; 47 48 fns = io_pgtable_init_table[fmt]; 49 if (!fns) 50 return NULL; 51 52 iop = fns->alloc(cfg, cookie); 53 if (!iop) 54 return NULL; 55 56 iop->fmt = fmt; 57 iop->cookie = cookie; 58 iop->cfg = *cfg; 59 60 return &iop->ops; 61 } 62 63 /* 64 * It is the IOMMU driver's responsibility to ensure that the page table 65 * is no longer accessible to the walker by this point. 66 */ 67 void free_io_pgtable_ops(struct io_pgtable_ops *ops) 68 { 69 struct io_pgtable *iop; 70 71 if (!ops) 72 return; 73 74 iop = container_of(ops, struct io_pgtable, ops); 75 iop->cfg.tlb->tlb_flush_all(iop->cookie); 76 io_pgtable_init_table[iop->fmt]->free(iop); 77 } 78