98 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			98 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
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| /*
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|  * Generic page table allocator for IOMMUs.
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|  *
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|  * Copyright (C) 2014 ARM Limited
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|  *
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|  * Author: Will Deacon <will.deacon@arm.com>
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|  */
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| 
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| #include <linux/bug.h>
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| #include <linux/io-pgtable.h>
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| #include <linux/kernel.h>
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| #include <linux/types.h>
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| 
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| static const struct io_pgtable_init_fns *
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| io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
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| #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
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| 	[ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
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| 	[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
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| 	[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
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| 	[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
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| 	[ARM_MALI_LPAE] = &io_pgtable_arm_mali_lpae_init_fns,
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| #endif
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| #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
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| 	[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
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| #endif
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| #ifdef CONFIG_AMD_IOMMU
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| 	[AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns,
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| 	[AMD_IOMMU_V2] = &io_pgtable_amd_iommu_v2_init_fns,
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| #endif
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| };
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| 
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| static int check_custom_allocator(enum io_pgtable_fmt fmt,
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| 				  struct io_pgtable_cfg *cfg)
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| {
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| 	/* No custom allocator, no need to check the format. */
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| 	if (!cfg->alloc && !cfg->free)
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| 		return 0;
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| 
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| 	/* When passing a custom allocator, both the alloc and free
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| 	 * functions should be provided.
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| 	 */
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| 	if (!cfg->alloc || !cfg->free)
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| 		return -EINVAL;
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| 
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| 	/* Make sure the format supports custom allocators. */
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| 	if (io_pgtable_init_table[fmt]->caps & IO_PGTABLE_CAP_CUSTOM_ALLOCATOR)
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| 		return 0;
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| 
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| 	return -EINVAL;
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| }
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| 
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| struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
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| 					    struct io_pgtable_cfg *cfg,
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| 					    void *cookie)
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| {
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| 	struct io_pgtable *iop;
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| 	const struct io_pgtable_init_fns *fns;
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| 
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| 	if (fmt >= IO_PGTABLE_NUM_FMTS)
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| 		return NULL;
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| 
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| 	if (check_custom_allocator(fmt, cfg))
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| 		return NULL;
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| 
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| 	fns = io_pgtable_init_table[fmt];
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| 	if (!fns)
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| 		return NULL;
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| 
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| 	iop = fns->alloc(cfg, cookie);
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| 	if (!iop)
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| 		return NULL;
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| 
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| 	iop->fmt	= fmt;
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| 	iop->cookie	= cookie;
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| 	iop->cfg	= *cfg;
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| 
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| 	return &iop->ops;
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| }
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| EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
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| 
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| /*
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|  * It is the IOMMU driver's responsibility to ensure that the page table
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|  * is no longer accessible to the walker by this point.
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|  */
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| void free_io_pgtable_ops(struct io_pgtable_ops *ops)
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| {
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| 	struct io_pgtable *iop;
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| 
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| 	if (!ops)
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| 		return;
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| 
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| 	iop = io_pgtable_ops_to_pgtable(ops);
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| 	io_pgtable_tlb_flush_all(iop);
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| 	io_pgtable_init_table[iop->fmt]->free(iop);
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| }
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| EXPORT_SYMBOL_GPL(free_io_pgtable_ops);
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