1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * CPU-agnostic ARM page table allocator.
4  *
5  * Copyright (C) 2014 ARM Limited
6  *
7  * Author: Will Deacon <will.deacon@arm.com>
8  */
9 
10 #define pr_fmt(fmt)	"arm-lpae io-pgtable: " fmt
11 
12 #include <linux/atomic.h>
13 #include <linux/bitops.h>
14 #include <linux/io-pgtable.h>
15 #include <linux/kernel.h>
16 #include <linux/sizes.h>
17 #include <linux/slab.h>
18 #include <linux/types.h>
19 #include <linux/dma-mapping.h>
20 
21 #include <asm/barrier.h>
22 
23 #include "io-pgtable-arm.h"
24 
25 #define ARM_LPAE_MAX_ADDR_BITS		52
26 #define ARM_LPAE_S2_MAX_CONCAT_PAGES	16
27 #define ARM_LPAE_MAX_LEVELS		4
28 
29 /* Struct accessors */
30 #define io_pgtable_to_data(x)						\
31 	container_of((x), struct arm_lpae_io_pgtable, iop)
32 
33 #define io_pgtable_ops_to_data(x)					\
34 	io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
35 
36 /*
37  * Calculate the right shift amount to get to the portion describing level l
38  * in a virtual address mapped by the pagetable in d.
39  */
40 #define ARM_LPAE_LVL_SHIFT(l,d)						\
41 	(((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level) +		\
42 	ilog2(sizeof(arm_lpae_iopte)))
43 
44 #define ARM_LPAE_GRANULE(d)						\
45 	(sizeof(arm_lpae_iopte) << (d)->bits_per_level)
46 #define ARM_LPAE_PGD_SIZE(d)						\
47 	(sizeof(arm_lpae_iopte) << (d)->pgd_bits)
48 
49 #define ARM_LPAE_PTES_PER_TABLE(d)					\
50 	(ARM_LPAE_GRANULE(d) >> ilog2(sizeof(arm_lpae_iopte)))
51 
52 /*
53  * Calculate the index at level l used to map virtual address a using the
54  * pagetable in d.
55  */
56 #define ARM_LPAE_PGD_IDX(l,d)						\
57 	((l) == (d)->start_level ? (d)->pgd_bits - (d)->bits_per_level : 0)
58 
59 #define ARM_LPAE_LVL_IDX(a,l,d)						\
60 	(((u64)(a) >> ARM_LPAE_LVL_SHIFT(l,d)) &			\
61 	 ((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1))
62 
63 /* Calculate the block/page mapping size at level l for pagetable in d. */
64 #define ARM_LPAE_BLOCK_SIZE(l,d)	(1ULL << ARM_LPAE_LVL_SHIFT(l,d))
65 
66 /* Page table bits */
67 #define ARM_LPAE_PTE_TYPE_SHIFT		0
68 #define ARM_LPAE_PTE_TYPE_MASK		0x3
69 
70 #define ARM_LPAE_PTE_TYPE_BLOCK		1
71 #define ARM_LPAE_PTE_TYPE_TABLE		3
72 #define ARM_LPAE_PTE_TYPE_PAGE		3
73 
74 #define ARM_LPAE_PTE_ADDR_MASK		GENMASK_ULL(47,12)
75 
76 #define ARM_LPAE_PTE_NSTABLE		(((arm_lpae_iopte)1) << 63)
77 #define ARM_LPAE_PTE_XN			(((arm_lpae_iopte)3) << 53)
78 #define ARM_LPAE_PTE_AF			(((arm_lpae_iopte)1) << 10)
79 #define ARM_LPAE_PTE_SH_NS		(((arm_lpae_iopte)0) << 8)
80 #define ARM_LPAE_PTE_SH_OS		(((arm_lpae_iopte)2) << 8)
81 #define ARM_LPAE_PTE_SH_IS		(((arm_lpae_iopte)3) << 8)
82 #define ARM_LPAE_PTE_NS			(((arm_lpae_iopte)1) << 5)
83 #define ARM_LPAE_PTE_VALID		(((arm_lpae_iopte)1) << 0)
84 
85 #define ARM_LPAE_PTE_ATTR_LO_MASK	(((arm_lpae_iopte)0x3ff) << 2)
86 /* Ignore the contiguous bit for block splitting */
87 #define ARM_LPAE_PTE_ATTR_HI_MASK	(((arm_lpae_iopte)6) << 52)
88 #define ARM_LPAE_PTE_ATTR_MASK		(ARM_LPAE_PTE_ATTR_LO_MASK |	\
89 					 ARM_LPAE_PTE_ATTR_HI_MASK)
90 /* Software bit for solving coherency races */
91 #define ARM_LPAE_PTE_SW_SYNC		(((arm_lpae_iopte)1) << 55)
92 
93 /* Stage-1 PTE */
94 #define ARM_LPAE_PTE_AP_UNPRIV		(((arm_lpae_iopte)1) << 6)
95 #define ARM_LPAE_PTE_AP_RDONLY		(((arm_lpae_iopte)2) << 6)
96 #define ARM_LPAE_PTE_ATTRINDX_SHIFT	2
97 #define ARM_LPAE_PTE_nG			(((arm_lpae_iopte)1) << 11)
98 
99 /* Stage-2 PTE */
100 #define ARM_LPAE_PTE_HAP_FAULT		(((arm_lpae_iopte)0) << 6)
101 #define ARM_LPAE_PTE_HAP_READ		(((arm_lpae_iopte)1) << 6)
102 #define ARM_LPAE_PTE_HAP_WRITE		(((arm_lpae_iopte)2) << 6)
103 #define ARM_LPAE_PTE_MEMATTR_OIWB	(((arm_lpae_iopte)0xf) << 2)
104 #define ARM_LPAE_PTE_MEMATTR_NC		(((arm_lpae_iopte)0x5) << 2)
105 #define ARM_LPAE_PTE_MEMATTR_DEV	(((arm_lpae_iopte)0x1) << 2)
106 
107 /* Register bits */
108 #define ARM_LPAE_VTCR_SL0_MASK		0x3
109 
110 #define ARM_LPAE_TCR_T0SZ_SHIFT		0
111 
112 #define ARM_LPAE_VTCR_PS_SHIFT		16
113 #define ARM_LPAE_VTCR_PS_MASK		0x7
114 
115 #define ARM_LPAE_MAIR_ATTR_SHIFT(n)	((n) << 3)
116 #define ARM_LPAE_MAIR_ATTR_MASK		0xff
117 #define ARM_LPAE_MAIR_ATTR_DEVICE	0x04
118 #define ARM_LPAE_MAIR_ATTR_NC		0x44
119 #define ARM_LPAE_MAIR_ATTR_INC_OWBRWA	0xf4
120 #define ARM_LPAE_MAIR_ATTR_WBRWA	0xff
121 #define ARM_LPAE_MAIR_ATTR_IDX_NC	0
122 #define ARM_LPAE_MAIR_ATTR_IDX_CACHE	1
123 #define ARM_LPAE_MAIR_ATTR_IDX_DEV	2
124 #define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE	3
125 
126 #define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
127 #define ARM_MALI_LPAE_TTBR_READ_INNER	BIT(2)
128 #define ARM_MALI_LPAE_TTBR_SHARE_OUTER	BIT(4)
129 
130 #define ARM_MALI_LPAE_MEMATTR_IMP_DEF	0x88ULL
131 #define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
132 
133 /* IOPTE accessors */
134 #define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
135 
136 #define iopte_type(pte)					\
137 	(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
138 
139 #define iopte_prot(pte)	((pte) & ARM_LPAE_PTE_ATTR_MASK)
140 
141 struct arm_lpae_io_pgtable {
142 	struct io_pgtable	iop;
143 
144 	int			pgd_bits;
145 	int			start_level;
146 	int			bits_per_level;
147 
148 	void			*pgd;
149 };
150 
151 typedef u64 arm_lpae_iopte;
152 
iopte_leaf(arm_lpae_iopte pte,int lvl,enum io_pgtable_fmt fmt)153 static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
154 			      enum io_pgtable_fmt fmt)
155 {
156 	if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
157 		return iopte_type(pte) == ARM_LPAE_PTE_TYPE_PAGE;
158 
159 	return iopte_type(pte) == ARM_LPAE_PTE_TYPE_BLOCK;
160 }
161 
paddr_to_iopte(phys_addr_t paddr,struct arm_lpae_io_pgtable * data)162 static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
163 				     struct arm_lpae_io_pgtable *data)
164 {
165 	arm_lpae_iopte pte = paddr;
166 
167 	/* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */
168 	return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK;
169 }
170 
iopte_to_paddr(arm_lpae_iopte pte,struct arm_lpae_io_pgtable * data)171 static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
172 				  struct arm_lpae_io_pgtable *data)
173 {
174 	u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
175 
176 	if (ARM_LPAE_GRANULE(data) < SZ_64K)
177 		return paddr;
178 
179 	/* Rotate the packed high-order bits back to the top */
180 	return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4);
181 }
182 
183 static bool selftest_running = false;
184 
__arm_lpae_dma_addr(void * pages)185 static dma_addr_t __arm_lpae_dma_addr(void *pages)
186 {
187 	return (dma_addr_t)virt_to_phys(pages);
188 }
189 
__arm_lpae_alloc_pages(size_t size,gfp_t gfp,struct io_pgtable_cfg * cfg)190 static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
191 				    struct io_pgtable_cfg *cfg)
192 {
193 	struct device *dev = cfg->iommu_dev;
194 	int order = get_order(size);
195 	struct page *p;
196 	dma_addr_t dma;
197 	void *pages;
198 
199 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
200 	p = alloc_pages_node(dev_to_node(dev), gfp | __GFP_ZERO, order);
201 	if (!p)
202 		return NULL;
203 
204 	pages = page_address(p);
205 	if (!cfg->coherent_walk) {
206 		dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
207 		if (dma_mapping_error(dev, dma))
208 			goto out_free;
209 		/*
210 		 * We depend on the IOMMU being able to work with any physical
211 		 * address directly, so if the DMA layer suggests otherwise by
212 		 * translating or truncating them, that bodes very badly...
213 		 */
214 		if (dma != virt_to_phys(pages))
215 			goto out_unmap;
216 	}
217 
218 	return pages;
219 
220 out_unmap:
221 	dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n");
222 	dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
223 out_free:
224 	__free_pages(p, order);
225 	return NULL;
226 }
227 
__arm_lpae_free_pages(void * pages,size_t size,struct io_pgtable_cfg * cfg)228 static void __arm_lpae_free_pages(void *pages, size_t size,
229 				  struct io_pgtable_cfg *cfg)
230 {
231 	if (!cfg->coherent_walk)
232 		dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages),
233 				 size, DMA_TO_DEVICE);
234 	free_pages((unsigned long)pages, get_order(size));
235 }
236 
__arm_lpae_sync_pte(arm_lpae_iopte * ptep,int num_entries,struct io_pgtable_cfg * cfg)237 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
238 				struct io_pgtable_cfg *cfg)
239 {
240 	dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
241 				   sizeof(*ptep) * num_entries, DMA_TO_DEVICE);
242 }
243 
__arm_lpae_clear_pte(arm_lpae_iopte * ptep,struct io_pgtable_cfg * cfg)244 static void __arm_lpae_clear_pte(arm_lpae_iopte *ptep, struct io_pgtable_cfg *cfg)
245 {
246 
247 	*ptep = 0;
248 
249 	if (!cfg->coherent_walk)
250 		__arm_lpae_sync_pte(ptep, 1, cfg);
251 }
252 
253 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
254 			       struct iommu_iotlb_gather *gather,
255 			       unsigned long iova, size_t size, size_t pgcount,
256 			       int lvl, arm_lpae_iopte *ptep);
257 
__arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,int num_entries,arm_lpae_iopte * ptep)258 static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
259 				phys_addr_t paddr, arm_lpae_iopte prot,
260 				int lvl, int num_entries, arm_lpae_iopte *ptep)
261 {
262 	arm_lpae_iopte pte = prot;
263 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
264 	size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
265 	int i;
266 
267 	if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
268 		pte |= ARM_LPAE_PTE_TYPE_PAGE;
269 	else
270 		pte |= ARM_LPAE_PTE_TYPE_BLOCK;
271 
272 	for (i = 0; i < num_entries; i++)
273 		ptep[i] = pte | paddr_to_iopte(paddr + i * sz, data);
274 
275 	if (!cfg->coherent_walk)
276 		__arm_lpae_sync_pte(ptep, num_entries, cfg);
277 }
278 
arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,int num_entries,arm_lpae_iopte * ptep)279 static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
280 			     unsigned long iova, phys_addr_t paddr,
281 			     arm_lpae_iopte prot, int lvl, int num_entries,
282 			     arm_lpae_iopte *ptep)
283 {
284 	int i;
285 
286 	for (i = 0; i < num_entries; i++)
287 		if (iopte_leaf(ptep[i], lvl, data->iop.fmt)) {
288 			/* We require an unmap first */
289 			WARN_ON(!selftest_running);
290 			return -EEXIST;
291 		} else if (iopte_type(ptep[i]) == ARM_LPAE_PTE_TYPE_TABLE) {
292 			/*
293 			 * We need to unmap and free the old table before
294 			 * overwriting it with a block entry.
295 			 */
296 			arm_lpae_iopte *tblp;
297 			size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
298 
299 			tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
300 			if (__arm_lpae_unmap(data, NULL, iova + i * sz, sz, 1,
301 					     lvl, tblp) != sz) {
302 				WARN_ON(1);
303 				return -EINVAL;
304 			}
305 		}
306 
307 	__arm_lpae_init_pte(data, paddr, prot, lvl, num_entries, ptep);
308 	return 0;
309 }
310 
arm_lpae_install_table(arm_lpae_iopte * table,arm_lpae_iopte * ptep,arm_lpae_iopte curr,struct arm_lpae_io_pgtable * data)311 static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
312 					     arm_lpae_iopte *ptep,
313 					     arm_lpae_iopte curr,
314 					     struct arm_lpae_io_pgtable *data)
315 {
316 	arm_lpae_iopte old, new;
317 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
318 
319 	new = paddr_to_iopte(__pa(table), data) | ARM_LPAE_PTE_TYPE_TABLE;
320 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
321 		new |= ARM_LPAE_PTE_NSTABLE;
322 
323 	/*
324 	 * Ensure the table itself is visible before its PTE can be.
325 	 * Whilst we could get away with cmpxchg64_release below, this
326 	 * doesn't have any ordering semantics when !CONFIG_SMP.
327 	 */
328 	dma_wmb();
329 
330 	old = cmpxchg64_relaxed(ptep, curr, new);
331 
332 	if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC))
333 		return old;
334 
335 	/* Even if it's not ours, there's no point waiting; just kick it */
336 	__arm_lpae_sync_pte(ptep, 1, cfg);
337 	if (old == curr)
338 		WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC);
339 
340 	return old;
341 }
342 
__arm_lpae_map(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,size_t size,size_t pgcount,arm_lpae_iopte prot,int lvl,arm_lpae_iopte * ptep,gfp_t gfp,size_t * mapped)343 static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
344 			  phys_addr_t paddr, size_t size, size_t pgcount,
345 			  arm_lpae_iopte prot, int lvl, arm_lpae_iopte *ptep,
346 			  gfp_t gfp, size_t *mapped)
347 {
348 	arm_lpae_iopte *cptep, pte;
349 	size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
350 	size_t tblsz = ARM_LPAE_GRANULE(data);
351 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
352 	int ret = 0, num_entries, max_entries, map_idx_start;
353 
354 	/* Find our entry at the current level */
355 	map_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
356 	ptep += map_idx_start;
357 
358 	/* If we can install a leaf entry at this level, then do so */
359 	if (size == block_size) {
360 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - map_idx_start;
361 		num_entries = min_t(int, pgcount, max_entries);
362 		ret = arm_lpae_init_pte(data, iova, paddr, prot, lvl, num_entries, ptep);
363 		if (!ret)
364 			*mapped += num_entries * size;
365 
366 		return ret;
367 	}
368 
369 	/* We can't allocate tables at the final level */
370 	if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
371 		return -EINVAL;
372 
373 	/* Grab a pointer to the next level */
374 	pte = READ_ONCE(*ptep);
375 	if (!pte) {
376 		cptep = __arm_lpae_alloc_pages(tblsz, gfp, cfg);
377 		if (!cptep)
378 			return -ENOMEM;
379 
380 		pte = arm_lpae_install_table(cptep, ptep, 0, data);
381 		if (pte)
382 			__arm_lpae_free_pages(cptep, tblsz, cfg);
383 	} else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) {
384 		__arm_lpae_sync_pte(ptep, 1, cfg);
385 	}
386 
387 	if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
388 		cptep = iopte_deref(pte, data);
389 	} else if (pte) {
390 		/* We require an unmap first */
391 		WARN_ON(!selftest_running);
392 		return -EEXIST;
393 	}
394 
395 	/* Rinse, repeat */
396 	return __arm_lpae_map(data, iova, paddr, size, pgcount, prot, lvl + 1,
397 			      cptep, gfp, mapped);
398 }
399 
arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable * data,int prot)400 static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
401 					   int prot)
402 {
403 	arm_lpae_iopte pte;
404 
405 	if (data->iop.fmt == ARM_64_LPAE_S1 ||
406 	    data->iop.fmt == ARM_32_LPAE_S1) {
407 		pte = ARM_LPAE_PTE_nG;
408 		if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
409 			pte |= ARM_LPAE_PTE_AP_RDONLY;
410 		if (!(prot & IOMMU_PRIV))
411 			pte |= ARM_LPAE_PTE_AP_UNPRIV;
412 	} else {
413 		pte = ARM_LPAE_PTE_HAP_FAULT;
414 		if (prot & IOMMU_READ)
415 			pte |= ARM_LPAE_PTE_HAP_READ;
416 		if (prot & IOMMU_WRITE)
417 			pte |= ARM_LPAE_PTE_HAP_WRITE;
418 	}
419 
420 	/*
421 	 * Note that this logic is structured to accommodate Mali LPAE
422 	 * having stage-1-like attributes but stage-2-like permissions.
423 	 */
424 	if (data->iop.fmt == ARM_64_LPAE_S2 ||
425 	    data->iop.fmt == ARM_32_LPAE_S2) {
426 		if (prot & IOMMU_MMIO)
427 			pte |= ARM_LPAE_PTE_MEMATTR_DEV;
428 		else if (prot & IOMMU_CACHE)
429 			pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
430 		else
431 			pte |= ARM_LPAE_PTE_MEMATTR_NC;
432 	} else {
433 		if (prot & IOMMU_MMIO)
434 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
435 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
436 		else if (prot & IOMMU_CACHE)
437 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
438 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
439 	}
440 
441 	/*
442 	 * Also Mali has its own notions of shareability wherein its Inner
443 	 * domain covers the cores within the GPU, and its Outer domain is
444 	 * "outside the GPU" (i.e. either the Inner or System domain in CPU
445 	 * terms, depending on coherency).
446 	 */
447 	if (prot & IOMMU_CACHE && data->iop.fmt != ARM_MALI_LPAE)
448 		pte |= ARM_LPAE_PTE_SH_IS;
449 	else
450 		pte |= ARM_LPAE_PTE_SH_OS;
451 
452 	if (prot & IOMMU_NOEXEC)
453 		pte |= ARM_LPAE_PTE_XN;
454 
455 	if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
456 		pte |= ARM_LPAE_PTE_NS;
457 
458 	if (data->iop.fmt != ARM_MALI_LPAE)
459 		pte |= ARM_LPAE_PTE_AF;
460 
461 	return pte;
462 }
463 
arm_lpae_map_pages(struct io_pgtable_ops * ops,unsigned long iova,phys_addr_t paddr,size_t pgsize,size_t pgcount,int iommu_prot,gfp_t gfp,size_t * mapped)464 static int arm_lpae_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
465 			      phys_addr_t paddr, size_t pgsize, size_t pgcount,
466 			      int iommu_prot, gfp_t gfp, size_t *mapped)
467 {
468 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
469 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
470 	arm_lpae_iopte *ptep = data->pgd;
471 	int ret, lvl = data->start_level;
472 	arm_lpae_iopte prot;
473 	long iaext = (s64)iova >> cfg->ias;
474 
475 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize))
476 		return -EINVAL;
477 
478 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
479 		iaext = ~iaext;
480 	if (WARN_ON(iaext || paddr >> cfg->oas))
481 		return -ERANGE;
482 
483 	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
484 		return -EINVAL;
485 
486 	prot = arm_lpae_prot_to_pte(data, iommu_prot);
487 	ret = __arm_lpae_map(data, iova, paddr, pgsize, pgcount, prot, lvl,
488 			     ptep, gfp, mapped);
489 	/*
490 	 * Synchronise all PTE updates for the new mapping before there's
491 	 * a chance for anything to kick off a table walk for the new iova.
492 	 */
493 	wmb();
494 
495 	return ret;
496 }
497 
__arm_lpae_free_pgtable(struct arm_lpae_io_pgtable * data,int lvl,arm_lpae_iopte * ptep)498 static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
499 				    arm_lpae_iopte *ptep)
500 {
501 	arm_lpae_iopte *start, *end;
502 	unsigned long table_size;
503 
504 	if (lvl == data->start_level)
505 		table_size = ARM_LPAE_PGD_SIZE(data);
506 	else
507 		table_size = ARM_LPAE_GRANULE(data);
508 
509 	start = ptep;
510 
511 	/* Only leaf entries at the last level */
512 	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
513 		end = ptep;
514 	else
515 		end = (void *)ptep + table_size;
516 
517 	while (ptep != end) {
518 		arm_lpae_iopte pte = *ptep++;
519 
520 		if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
521 			continue;
522 
523 		__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
524 	}
525 
526 	__arm_lpae_free_pages(start, table_size, &data->iop.cfg);
527 }
528 
arm_lpae_free_pgtable(struct io_pgtable * iop)529 static void arm_lpae_free_pgtable(struct io_pgtable *iop)
530 {
531 	struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
532 
533 	__arm_lpae_free_pgtable(data, data->start_level, data->pgd);
534 	kfree(data);
535 }
536 
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,size_t pgcount)537 static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
538 				       struct iommu_iotlb_gather *gather,
539 				       unsigned long iova, size_t size,
540 				       arm_lpae_iopte blk_pte, int lvl,
541 				       arm_lpae_iopte *ptep, size_t pgcount)
542 {
543 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
544 	arm_lpae_iopte pte, *tablep;
545 	phys_addr_t blk_paddr;
546 	size_t tablesz = ARM_LPAE_GRANULE(data);
547 	size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
548 	int ptes_per_table = ARM_LPAE_PTES_PER_TABLE(data);
549 	int i, unmap_idx_start = -1, num_entries = 0, max_entries;
550 
551 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
552 		return 0;
553 
554 	tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg);
555 	if (!tablep)
556 		return 0; /* Bytes unmapped */
557 
558 	if (size == split_sz) {
559 		unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
560 		max_entries = ptes_per_table - unmap_idx_start;
561 		num_entries = min_t(int, pgcount, max_entries);
562 	}
563 
564 	blk_paddr = iopte_to_paddr(blk_pte, data);
565 	pte = iopte_prot(blk_pte);
566 
567 	for (i = 0; i < ptes_per_table; i++, blk_paddr += split_sz) {
568 		/* Unmap! */
569 		if (i >= unmap_idx_start && i < (unmap_idx_start + num_entries))
570 			continue;
571 
572 		__arm_lpae_init_pte(data, blk_paddr, pte, lvl, 1, &tablep[i]);
573 	}
574 
575 	pte = arm_lpae_install_table(tablep, ptep, blk_pte, data);
576 	if (pte != blk_pte) {
577 		__arm_lpae_free_pages(tablep, tablesz, cfg);
578 		/*
579 		 * We may race against someone unmapping another part of this
580 		 * block, but anything else is invalid. We can't misinterpret
581 		 * a page entry here since we're never at the last level.
582 		 */
583 		if (iopte_type(pte) != ARM_LPAE_PTE_TYPE_TABLE)
584 			return 0;
585 
586 		tablep = iopte_deref(pte, data);
587 	} else if (unmap_idx_start >= 0) {
588 		for (i = 0; i < num_entries; i++)
589 			io_pgtable_tlb_add_page(&data->iop, gather, iova + i * size, size);
590 
591 		return num_entries * size;
592 	}
593 
594 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl, tablep);
595 }
596 
__arm_lpae_unmap(struct arm_lpae_io_pgtable * data,struct iommu_iotlb_gather * gather,unsigned long iova,size_t size,size_t pgcount,int lvl,arm_lpae_iopte * ptep)597 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
598 			       struct iommu_iotlb_gather *gather,
599 			       unsigned long iova, size_t size, size_t pgcount,
600 			       int lvl, arm_lpae_iopte *ptep)
601 {
602 	arm_lpae_iopte pte;
603 	struct io_pgtable *iop = &data->iop;
604 	int i = 0, num_entries, max_entries, unmap_idx_start;
605 
606 	/* Something went horribly wrong and we ran out of page table */
607 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
608 		return 0;
609 
610 	unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
611 	ptep += unmap_idx_start;
612 	pte = READ_ONCE(*ptep);
613 	if (WARN_ON(!pte))
614 		return 0;
615 
616 	/* If the size matches this level, we're in the right place */
617 	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
618 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - unmap_idx_start;
619 		num_entries = min_t(int, pgcount, max_entries);
620 
621 		while (i < num_entries) {
622 			pte = READ_ONCE(*ptep);
623 			if (WARN_ON(!pte))
624 				break;
625 
626 			__arm_lpae_clear_pte(ptep, &iop->cfg);
627 
628 			if (!iopte_leaf(pte, lvl, iop->fmt)) {
629 				/* Also flush any partial walks */
630 				io_pgtable_tlb_flush_walk(iop, iova + i * size, size,
631 							  ARM_LPAE_GRANULE(data));
632 				__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
633 			} else if (!iommu_iotlb_gather_queued(gather)) {
634 				io_pgtable_tlb_add_page(iop, gather, iova + i * size, size);
635 			}
636 
637 			ptep++;
638 			i++;
639 		}
640 
641 		return i * size;
642 	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
643 		/*
644 		 * Insert a table at the next level to map the old region,
645 		 * minus the part we want to unmap
646 		 */
647 		return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
648 						lvl + 1, ptep, pgcount);
649 	}
650 
651 	/* Keep on walkin' */
652 	ptep = iopte_deref(pte, data);
653 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl + 1, ptep);
654 }
655 
arm_lpae_unmap_pages(struct io_pgtable_ops * ops,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)656 static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iova,
657 				   size_t pgsize, size_t pgcount,
658 				   struct iommu_iotlb_gather *gather)
659 {
660 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
661 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
662 	arm_lpae_iopte *ptep = data->pgd;
663 	long iaext = (s64)iova >> cfg->ias;
664 
665 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize || !pgcount))
666 		return 0;
667 
668 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
669 		iaext = ~iaext;
670 	if (WARN_ON(iaext))
671 		return 0;
672 
673 	return __arm_lpae_unmap(data, gather, iova, pgsize, pgcount,
674 				data->start_level, ptep);
675 }
676 
arm_lpae_iova_to_phys(struct io_pgtable_ops * ops,unsigned long iova)677 static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
678 					 unsigned long iova)
679 {
680 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
681 	arm_lpae_iopte pte, *ptep = data->pgd;
682 	int lvl = data->start_level;
683 
684 	do {
685 		/* Valid IOPTE pointer? */
686 		if (!ptep)
687 			return 0;
688 
689 		/* Grab the IOPTE we're interested in */
690 		ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
691 		pte = READ_ONCE(*ptep);
692 
693 		/* Valid entry? */
694 		if (!pte)
695 			return 0;
696 
697 		/* Leaf entry? */
698 		if (iopte_leaf(pte, lvl, data->iop.fmt))
699 			goto found_translation;
700 
701 		/* Take it to the next level */
702 		ptep = iopte_deref(pte, data);
703 	} while (++lvl < ARM_LPAE_MAX_LEVELS);
704 
705 	/* Ran out of page tables to walk */
706 	return 0;
707 
708 found_translation:
709 	iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
710 	return iopte_to_paddr(pte, data) | iova;
711 }
712 
arm_lpae_restrict_pgsizes(struct io_pgtable_cfg * cfg)713 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
714 {
715 	unsigned long granule, page_sizes;
716 	unsigned int max_addr_bits = 48;
717 
718 	/*
719 	 * We need to restrict the supported page sizes to match the
720 	 * translation regime for a particular granule. Aim to match
721 	 * the CPU page size if possible, otherwise prefer smaller sizes.
722 	 * While we're at it, restrict the block sizes to match the
723 	 * chosen granule.
724 	 */
725 	if (cfg->pgsize_bitmap & PAGE_SIZE)
726 		granule = PAGE_SIZE;
727 	else if (cfg->pgsize_bitmap & ~PAGE_MASK)
728 		granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK);
729 	else if (cfg->pgsize_bitmap & PAGE_MASK)
730 		granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK);
731 	else
732 		granule = 0;
733 
734 	switch (granule) {
735 	case SZ_4K:
736 		page_sizes = (SZ_4K | SZ_2M | SZ_1G);
737 		break;
738 	case SZ_16K:
739 		page_sizes = (SZ_16K | SZ_32M);
740 		break;
741 	case SZ_64K:
742 		max_addr_bits = 52;
743 		page_sizes = (SZ_64K | SZ_512M);
744 		if (cfg->oas > 48)
745 			page_sizes |= 1ULL << 42; /* 4TB */
746 		break;
747 	default:
748 		page_sizes = 0;
749 	}
750 
751 	cfg->pgsize_bitmap &= page_sizes;
752 	cfg->ias = min(cfg->ias, max_addr_bits);
753 	cfg->oas = min(cfg->oas, max_addr_bits);
754 }
755 
756 static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg)757 arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
758 {
759 	struct arm_lpae_io_pgtable *data;
760 	int levels, va_bits, pg_shift;
761 
762 	arm_lpae_restrict_pgsizes(cfg);
763 
764 	if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K)))
765 		return NULL;
766 
767 	if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS)
768 		return NULL;
769 
770 	if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
771 		return NULL;
772 
773 	data = kmalloc(sizeof(*data), GFP_KERNEL);
774 	if (!data)
775 		return NULL;
776 
777 	pg_shift = __ffs(cfg->pgsize_bitmap);
778 	data->bits_per_level = pg_shift - ilog2(sizeof(arm_lpae_iopte));
779 
780 	va_bits = cfg->ias - pg_shift;
781 	levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
782 	data->start_level = ARM_LPAE_MAX_LEVELS - levels;
783 
784 	/* Calculate the actual size of our pgd (without concatenation) */
785 	data->pgd_bits = va_bits - (data->bits_per_level * (levels - 1));
786 
787 	data->iop.ops = (struct io_pgtable_ops) {
788 		.map_pages	= arm_lpae_map_pages,
789 		.unmap_pages	= arm_lpae_unmap_pages,
790 		.iova_to_phys	= arm_lpae_iova_to_phys,
791 	};
792 
793 	return data;
794 }
795 
796 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)797 arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
798 {
799 	u64 reg;
800 	struct arm_lpae_io_pgtable *data;
801 	typeof(&cfg->arm_lpae_s1_cfg.tcr) tcr = &cfg->arm_lpae_s1_cfg.tcr;
802 	bool tg1;
803 
804 	if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
805 			    IO_PGTABLE_QUIRK_ARM_TTBR1 |
806 			    IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
807 		return NULL;
808 
809 	data = arm_lpae_alloc_pgtable(cfg);
810 	if (!data)
811 		return NULL;
812 
813 	/* TCR */
814 	if (cfg->coherent_walk) {
815 		tcr->sh = ARM_LPAE_TCR_SH_IS;
816 		tcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
817 		tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
818 		if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA)
819 			goto out_free_data;
820 	} else {
821 		tcr->sh = ARM_LPAE_TCR_SH_OS;
822 		tcr->irgn = ARM_LPAE_TCR_RGN_NC;
823 		if (!(cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
824 			tcr->orgn = ARM_LPAE_TCR_RGN_NC;
825 		else
826 			tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
827 	}
828 
829 	tg1 = cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1;
830 	switch (ARM_LPAE_GRANULE(data)) {
831 	case SZ_4K:
832 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_4K : ARM_LPAE_TCR_TG0_4K;
833 		break;
834 	case SZ_16K:
835 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_16K : ARM_LPAE_TCR_TG0_16K;
836 		break;
837 	case SZ_64K:
838 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_64K : ARM_LPAE_TCR_TG0_64K;
839 		break;
840 	}
841 
842 	switch (cfg->oas) {
843 	case 32:
844 		tcr->ips = ARM_LPAE_TCR_PS_32_BIT;
845 		break;
846 	case 36:
847 		tcr->ips = ARM_LPAE_TCR_PS_36_BIT;
848 		break;
849 	case 40:
850 		tcr->ips = ARM_LPAE_TCR_PS_40_BIT;
851 		break;
852 	case 42:
853 		tcr->ips = ARM_LPAE_TCR_PS_42_BIT;
854 		break;
855 	case 44:
856 		tcr->ips = ARM_LPAE_TCR_PS_44_BIT;
857 		break;
858 	case 48:
859 		tcr->ips = ARM_LPAE_TCR_PS_48_BIT;
860 		break;
861 	case 52:
862 		tcr->ips = ARM_LPAE_TCR_PS_52_BIT;
863 		break;
864 	default:
865 		goto out_free_data;
866 	}
867 
868 	tcr->tsz = 64ULL - cfg->ias;
869 
870 	/* MAIRs */
871 	reg = (ARM_LPAE_MAIR_ATTR_NC
872 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
873 	      (ARM_LPAE_MAIR_ATTR_WBRWA
874 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
875 	      (ARM_LPAE_MAIR_ATTR_DEVICE
876 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) |
877 	      (ARM_LPAE_MAIR_ATTR_INC_OWBRWA
878 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE));
879 
880 	cfg->arm_lpae_s1_cfg.mair = reg;
881 
882 	/* Looking good; allocate a pgd */
883 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
884 					   GFP_KERNEL, cfg);
885 	if (!data->pgd)
886 		goto out_free_data;
887 
888 	/* Ensure the empty pgd is visible before any actual TTBR write */
889 	wmb();
890 
891 	/* TTBR */
892 	cfg->arm_lpae_s1_cfg.ttbr = virt_to_phys(data->pgd);
893 	return &data->iop;
894 
895 out_free_data:
896 	kfree(data);
897 	return NULL;
898 }
899 
900 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)901 arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
902 {
903 	u64 sl;
904 	struct arm_lpae_io_pgtable *data;
905 	typeof(&cfg->arm_lpae_s2_cfg.vtcr) vtcr = &cfg->arm_lpae_s2_cfg.vtcr;
906 
907 	/* The NS quirk doesn't apply at stage 2 */
908 	if (cfg->quirks)
909 		return NULL;
910 
911 	data = arm_lpae_alloc_pgtable(cfg);
912 	if (!data)
913 		return NULL;
914 
915 	/*
916 	 * Concatenate PGDs at level 1 if possible in order to reduce
917 	 * the depth of the stage-2 walk.
918 	 */
919 	if (data->start_level == 0) {
920 		unsigned long pgd_pages;
921 
922 		pgd_pages = ARM_LPAE_PGD_SIZE(data) / sizeof(arm_lpae_iopte);
923 		if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
924 			data->pgd_bits += data->bits_per_level;
925 			data->start_level++;
926 		}
927 	}
928 
929 	/* VTCR */
930 	if (cfg->coherent_walk) {
931 		vtcr->sh = ARM_LPAE_TCR_SH_IS;
932 		vtcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
933 		vtcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
934 	} else {
935 		vtcr->sh = ARM_LPAE_TCR_SH_OS;
936 		vtcr->irgn = ARM_LPAE_TCR_RGN_NC;
937 		vtcr->orgn = ARM_LPAE_TCR_RGN_NC;
938 	}
939 
940 	sl = data->start_level;
941 
942 	switch (ARM_LPAE_GRANULE(data)) {
943 	case SZ_4K:
944 		vtcr->tg = ARM_LPAE_TCR_TG0_4K;
945 		sl++; /* SL0 format is different for 4K granule size */
946 		break;
947 	case SZ_16K:
948 		vtcr->tg = ARM_LPAE_TCR_TG0_16K;
949 		break;
950 	case SZ_64K:
951 		vtcr->tg = ARM_LPAE_TCR_TG0_64K;
952 		break;
953 	}
954 
955 	switch (cfg->oas) {
956 	case 32:
957 		vtcr->ps = ARM_LPAE_TCR_PS_32_BIT;
958 		break;
959 	case 36:
960 		vtcr->ps = ARM_LPAE_TCR_PS_36_BIT;
961 		break;
962 	case 40:
963 		vtcr->ps = ARM_LPAE_TCR_PS_40_BIT;
964 		break;
965 	case 42:
966 		vtcr->ps = ARM_LPAE_TCR_PS_42_BIT;
967 		break;
968 	case 44:
969 		vtcr->ps = ARM_LPAE_TCR_PS_44_BIT;
970 		break;
971 	case 48:
972 		vtcr->ps = ARM_LPAE_TCR_PS_48_BIT;
973 		break;
974 	case 52:
975 		vtcr->ps = ARM_LPAE_TCR_PS_52_BIT;
976 		break;
977 	default:
978 		goto out_free_data;
979 	}
980 
981 	vtcr->tsz = 64ULL - cfg->ias;
982 	vtcr->sl = ~sl & ARM_LPAE_VTCR_SL0_MASK;
983 
984 	/* Allocate pgd pages */
985 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
986 					   GFP_KERNEL, cfg);
987 	if (!data->pgd)
988 		goto out_free_data;
989 
990 	/* Ensure the empty pgd is visible before any actual TTBR write */
991 	wmb();
992 
993 	/* VTTBR */
994 	cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
995 	return &data->iop;
996 
997 out_free_data:
998 	kfree(data);
999 	return NULL;
1000 }
1001 
1002 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)1003 arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
1004 {
1005 	if (cfg->ias > 32 || cfg->oas > 40)
1006 		return NULL;
1007 
1008 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1009 	return arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
1010 }
1011 
1012 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)1013 arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
1014 {
1015 	if (cfg->ias > 40 || cfg->oas > 40)
1016 		return NULL;
1017 
1018 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1019 	return arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
1020 }
1021 
1022 static struct io_pgtable *
arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg,void * cookie)1023 arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
1024 {
1025 	struct arm_lpae_io_pgtable *data;
1026 
1027 	/* No quirks for Mali (hopefully) */
1028 	if (cfg->quirks)
1029 		return NULL;
1030 
1031 	if (cfg->ias > 48 || cfg->oas > 40)
1032 		return NULL;
1033 
1034 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1035 
1036 	data = arm_lpae_alloc_pgtable(cfg);
1037 	if (!data)
1038 		return NULL;
1039 
1040 	/* Mali seems to need a full 4-level table regardless of IAS */
1041 	if (data->start_level > 0) {
1042 		data->start_level = 0;
1043 		data->pgd_bits = 0;
1044 	}
1045 	/*
1046 	 * MEMATTR: Mali has no actual notion of a non-cacheable type, so the
1047 	 * best we can do is mimic the out-of-tree driver and hope that the
1048 	 * "implementation-defined caching policy" is good enough. Similarly,
1049 	 * we'll use it for the sake of a valid attribute for our 'device'
1050 	 * index, although callers should never request that in practice.
1051 	 */
1052 	cfg->arm_mali_lpae_cfg.memattr =
1053 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1054 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
1055 		(ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC
1056 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
1057 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1058 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV));
1059 
1060 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL,
1061 					   cfg);
1062 	if (!data->pgd)
1063 		goto out_free_data;
1064 
1065 	/* Ensure the empty pgd is visible before TRANSTAB can be written */
1066 	wmb();
1067 
1068 	cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) |
1069 					  ARM_MALI_LPAE_TTBR_READ_INNER |
1070 					  ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
1071 	if (cfg->coherent_walk)
1072 		cfg->arm_mali_lpae_cfg.transtab |= ARM_MALI_LPAE_TTBR_SHARE_OUTER;
1073 
1074 	return &data->iop;
1075 
1076 out_free_data:
1077 	kfree(data);
1078 	return NULL;
1079 }
1080 
1081 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
1082 	.alloc	= arm_64_lpae_alloc_pgtable_s1,
1083 	.free	= arm_lpae_free_pgtable,
1084 };
1085 
1086 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = {
1087 	.alloc	= arm_64_lpae_alloc_pgtable_s2,
1088 	.free	= arm_lpae_free_pgtable,
1089 };
1090 
1091 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = {
1092 	.alloc	= arm_32_lpae_alloc_pgtable_s1,
1093 	.free	= arm_lpae_free_pgtable,
1094 };
1095 
1096 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
1097 	.alloc	= arm_32_lpae_alloc_pgtable_s2,
1098 	.free	= arm_lpae_free_pgtable,
1099 };
1100 
1101 struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
1102 	.alloc	= arm_mali_lpae_alloc_pgtable,
1103 	.free	= arm_lpae_free_pgtable,
1104 };
1105 
1106 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
1107 
1108 static struct io_pgtable_cfg *cfg_cookie __initdata;
1109 
dummy_tlb_flush_all(void * cookie)1110 static void __init dummy_tlb_flush_all(void *cookie)
1111 {
1112 	WARN_ON(cookie != cfg_cookie);
1113 }
1114 
dummy_tlb_flush(unsigned long iova,size_t size,size_t granule,void * cookie)1115 static void __init dummy_tlb_flush(unsigned long iova, size_t size,
1116 				   size_t granule, void *cookie)
1117 {
1118 	WARN_ON(cookie != cfg_cookie);
1119 	WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
1120 }
1121 
dummy_tlb_add_page(struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule,void * cookie)1122 static void __init dummy_tlb_add_page(struct iommu_iotlb_gather *gather,
1123 				      unsigned long iova, size_t granule,
1124 				      void *cookie)
1125 {
1126 	dummy_tlb_flush(iova, granule, granule, cookie);
1127 }
1128 
1129 static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
1130 	.tlb_flush_all	= dummy_tlb_flush_all,
1131 	.tlb_flush_walk	= dummy_tlb_flush,
1132 	.tlb_add_page	= dummy_tlb_add_page,
1133 };
1134 
arm_lpae_dump_ops(struct io_pgtable_ops * ops)1135 static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops)
1136 {
1137 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
1138 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
1139 
1140 	pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
1141 		cfg->pgsize_bitmap, cfg->ias);
1142 	pr_err("data: %d levels, 0x%zx pgd_size, %u pg_shift, %u bits_per_level, pgd @ %p\n",
1143 		ARM_LPAE_MAX_LEVELS - data->start_level, ARM_LPAE_PGD_SIZE(data),
1144 		ilog2(ARM_LPAE_GRANULE(data)), data->bits_per_level, data->pgd);
1145 }
1146 
1147 #define __FAIL(ops, i)	({						\
1148 		WARN(1, "selftest: test failed for fmt idx %d\n", (i));	\
1149 		arm_lpae_dump_ops(ops);					\
1150 		selftest_running = false;				\
1151 		-EFAULT;						\
1152 })
1153 
arm_lpae_run_tests(struct io_pgtable_cfg * cfg)1154 static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
1155 {
1156 	static const enum io_pgtable_fmt fmts[] __initconst = {
1157 		ARM_64_LPAE_S1,
1158 		ARM_64_LPAE_S2,
1159 	};
1160 
1161 	int i, j;
1162 	unsigned long iova;
1163 	size_t size, mapped;
1164 	struct io_pgtable_ops *ops;
1165 
1166 	selftest_running = true;
1167 
1168 	for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
1169 		cfg_cookie = cfg;
1170 		ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
1171 		if (!ops) {
1172 			pr_err("selftest: failed to allocate io pgtable ops\n");
1173 			return -ENOMEM;
1174 		}
1175 
1176 		/*
1177 		 * Initial sanity checks.
1178 		 * Empty page tables shouldn't provide any translations.
1179 		 */
1180 		if (ops->iova_to_phys(ops, 42))
1181 			return __FAIL(ops, i);
1182 
1183 		if (ops->iova_to_phys(ops, SZ_1G + 42))
1184 			return __FAIL(ops, i);
1185 
1186 		if (ops->iova_to_phys(ops, SZ_2G + 42))
1187 			return __FAIL(ops, i);
1188 
1189 		/*
1190 		 * Distinct mappings of different granule sizes.
1191 		 */
1192 		iova = 0;
1193 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1194 			size = 1UL << j;
1195 
1196 			if (ops->map_pages(ops, iova, iova, size, 1,
1197 					   IOMMU_READ | IOMMU_WRITE |
1198 					   IOMMU_NOEXEC | IOMMU_CACHE,
1199 					   GFP_KERNEL, &mapped))
1200 				return __FAIL(ops, i);
1201 
1202 			/* Overlapping mappings */
1203 			if (!ops->map_pages(ops, iova, iova + size, size, 1,
1204 					    IOMMU_READ | IOMMU_NOEXEC,
1205 					    GFP_KERNEL, &mapped))
1206 				return __FAIL(ops, i);
1207 
1208 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1209 				return __FAIL(ops, i);
1210 
1211 			iova += SZ_1G;
1212 		}
1213 
1214 		/* Partial unmap */
1215 		size = 1UL << __ffs(cfg->pgsize_bitmap);
1216 		if (ops->unmap_pages(ops, SZ_1G + size, size, 1, NULL) != size)
1217 			return __FAIL(ops, i);
1218 
1219 		/* Remap of partial unmap */
1220 		if (ops->map_pages(ops, SZ_1G + size, size, size, 1,
1221 				   IOMMU_READ, GFP_KERNEL, &mapped))
1222 			return __FAIL(ops, i);
1223 
1224 		if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
1225 			return __FAIL(ops, i);
1226 
1227 		/* Full unmap */
1228 		iova = 0;
1229 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1230 			size = 1UL << j;
1231 
1232 			if (ops->unmap_pages(ops, iova, size, 1, NULL) != size)
1233 				return __FAIL(ops, i);
1234 
1235 			if (ops->iova_to_phys(ops, iova + 42))
1236 				return __FAIL(ops, i);
1237 
1238 			/* Remap full block */
1239 			if (ops->map_pages(ops, iova, iova, size, 1,
1240 					   IOMMU_WRITE, GFP_KERNEL, &mapped))
1241 				return __FAIL(ops, i);
1242 
1243 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1244 				return __FAIL(ops, i);
1245 
1246 			iova += SZ_1G;
1247 		}
1248 
1249 		free_io_pgtable_ops(ops);
1250 	}
1251 
1252 	selftest_running = false;
1253 	return 0;
1254 }
1255 
arm_lpae_do_selftests(void)1256 static int __init arm_lpae_do_selftests(void)
1257 {
1258 	static const unsigned long pgsize[] __initconst = {
1259 		SZ_4K | SZ_2M | SZ_1G,
1260 		SZ_16K | SZ_32M,
1261 		SZ_64K | SZ_512M,
1262 	};
1263 
1264 	static const unsigned int ias[] __initconst = {
1265 		32, 36, 40, 42, 44, 48,
1266 	};
1267 
1268 	int i, j, pass = 0, fail = 0;
1269 	struct device dev;
1270 	struct io_pgtable_cfg cfg = {
1271 		.tlb = &dummy_tlb_ops,
1272 		.oas = 48,
1273 		.coherent_walk = true,
1274 		.iommu_dev = &dev,
1275 	};
1276 
1277 	/* __arm_lpae_alloc_pages() merely needs dev_to_node() to work */
1278 	set_dev_node(&dev, NUMA_NO_NODE);
1279 
1280 	for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
1281 		for (j = 0; j < ARRAY_SIZE(ias); ++j) {
1282 			cfg.pgsize_bitmap = pgsize[i];
1283 			cfg.ias = ias[j];
1284 			pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
1285 				pgsize[i], ias[j]);
1286 			if (arm_lpae_run_tests(&cfg))
1287 				fail++;
1288 			else
1289 				pass++;
1290 		}
1291 	}
1292 
1293 	pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
1294 	return fail ? -EFAULT : 0;
1295 }
1296 subsys_initcall(arm_lpae_do_selftests);
1297 #endif
1298