]> Git Repo - J-linux.git/blob - arch/arm/mm/ioremap.c
Merge tag 'vfs-6.13-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
[J-linux.git] / arch / arm / mm / ioremap.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/arch/arm/mm/ioremap.c
4  *
5  * Re-map IO memory to kernel address space so that we can access it.
6  *
7  * (C) Copyright 1995 1996 Linus Torvalds
8  *
9  * Hacked for ARM by Phil Blundell <[email protected]>
10  * Hacked to allow all architectures to build, and various cleanups
11  * by Russell King
12  *
13  * This allows a driver to remap an arbitrary region of bus memory into
14  * virtual space.  One should *only* use readl, writel, memcpy_toio and
15  * so on with such remapped areas.
16  *
17  * Because the ARM only has a 32-bit address space we can't address the
18  * whole of the (physical) PCI space at once.  PCI huge-mode addressing
19  * allows us to circumvent this restriction by splitting PCI space into
20  * two 2GB chunks and mapping only one at a time into processor memory.
21  * We use MMU protection domains to trap any attempt to access the bank
22  * that is not currently mapped.  (This isn't fully implemented yet.)
23  */
24 #include <linux/module.h>
25 #include <linux/errno.h>
26 #include <linux/kasan.h>
27 #include <linux/mm.h>
28 #include <linux/vmalloc.h>
29 #include <linux/io.h>
30 #include <linux/sizes.h>
31 #include <linux/memblock.h>
32
33 #include <asm/cp15.h>
34 #include <asm/cputype.h>
35 #include <asm/cacheflush.h>
36 #include <asm/early_ioremap.h>
37 #include <asm/mmu_context.h>
38 #include <asm/pgalloc.h>
39 #include <asm/tlbflush.h>
40 #include <asm/set_memory.h>
41 #include <asm/system_info.h>
42
43 #include <asm/mach/map.h>
44 #include <asm/mach/pci.h>
45 #include "mm.h"
46
47
48 LIST_HEAD(static_vmlist);
49
50 static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
51                         size_t size, unsigned int mtype)
52 {
53         struct static_vm *svm;
54         struct vm_struct *vm;
55
56         list_for_each_entry(svm, &static_vmlist, list) {
57                 vm = &svm->vm;
58                 if (!(vm->flags & VM_ARM_STATIC_MAPPING))
59                         continue;
60                 if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
61                         continue;
62
63                 if (vm->phys_addr > paddr ||
64                         paddr + size - 1 > vm->phys_addr + vm->size - 1)
65                         continue;
66
67                 return svm;
68         }
69
70         return NULL;
71 }
72
73 struct static_vm *find_static_vm_vaddr(void *vaddr)
74 {
75         struct static_vm *svm;
76         struct vm_struct *vm;
77
78         list_for_each_entry(svm, &static_vmlist, list) {
79                 vm = &svm->vm;
80
81                 /* static_vmlist is ascending order */
82                 if (vm->addr > vaddr)
83                         break;
84
85                 if (vm->addr <= vaddr && vm->addr + vm->size > vaddr)
86                         return svm;
87         }
88
89         return NULL;
90 }
91
92 void __init add_static_vm_early(struct static_vm *svm)
93 {
94         struct static_vm *curr_svm;
95         struct vm_struct *vm;
96         void *vaddr;
97
98         vm = &svm->vm;
99         vm_area_add_early(vm);
100         vaddr = vm->addr;
101
102         list_for_each_entry(curr_svm, &static_vmlist, list) {
103                 vm = &curr_svm->vm;
104
105                 if (vm->addr > vaddr)
106                         break;
107         }
108         list_add_tail(&svm->list, &curr_svm->list);
109 }
110
111 int ioremap_page(unsigned long virt, unsigned long phys,
112                  const struct mem_type *mtype)
113 {
114         return vmap_page_range(virt, virt + PAGE_SIZE, phys,
115                                __pgprot(mtype->prot_pte));
116 }
117 EXPORT_SYMBOL(ioremap_page);
118
119 #ifdef CONFIG_KASAN
120 static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)
121 {
122         return (unsigned long)kasan_mem_to_shadow((void *)addr);
123 }
124 #else
125 static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)
126 {
127         return 0;
128 }
129 #endif
130
131 static void memcpy_pgd(struct mm_struct *mm, unsigned long start,
132                        unsigned long end)
133 {
134         end = ALIGN(end, PGDIR_SIZE);
135         memcpy(pgd_offset(mm, start), pgd_offset_k(start),
136                sizeof(pgd_t) * (pgd_index(end) - pgd_index(start)));
137 }
138
139 void __check_vmalloc_seq(struct mm_struct *mm)
140 {
141         int seq;
142
143         do {
144                 seq = atomic_read_acquire(&init_mm.context.vmalloc_seq);
145                 memcpy_pgd(mm, VMALLOC_START, VMALLOC_END);
146                 if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
147                         unsigned long start =
148                                 arm_kasan_mem_to_shadow(VMALLOC_START);
149                         unsigned long end =
150                                 arm_kasan_mem_to_shadow(VMALLOC_END);
151                         memcpy_pgd(mm, start, end);
152                 }
153                 /*
154                  * Use a store-release so that other CPUs that observe the
155                  * counter's new value are guaranteed to see the results of the
156                  * memcpy as well.
157                  */
158                 atomic_set_release(&mm->context.vmalloc_seq, seq);
159         } while (seq != atomic_read(&init_mm.context.vmalloc_seq));
160 }
161
162 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
163 /*
164  * Section support is unsafe on SMP - If you iounmap and ioremap a region,
165  * the other CPUs will not see this change until their next context switch.
166  * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
167  * which requires the new ioremap'd region to be referenced, the CPU will
168  * reference the _old_ region.
169  *
170  * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
171  * mask the size back to 1MB aligned or we will overflow in the loop below.
172  */
173 static void unmap_area_sections(unsigned long virt, unsigned long size)
174 {
175         unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
176         pmd_t *pmdp = pmd_off_k(addr);
177
178         do {
179                 pmd_t pmd = *pmdp;
180
181                 if (!pmd_none(pmd)) {
182                         /*
183                          * Clear the PMD from the page table, and
184                          * increment the vmalloc sequence so others
185                          * notice this change.
186                          *
187                          * Note: this is still racy on SMP machines.
188                          */
189                         pmd_clear(pmdp);
190                         atomic_inc_return_release(&init_mm.context.vmalloc_seq);
191
192                         /*
193                          * Free the page table, if there was one.
194                          */
195                         if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
196                                 pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
197                 }
198
199                 addr += PMD_SIZE;
200                 pmdp += 2;
201         } while (addr < end);
202
203         /*
204          * Ensure that the active_mm is up to date - we want to
205          * catch any use-after-iounmap cases.
206          */
207         check_vmalloc_seq(current->active_mm);
208
209         flush_tlb_kernel_range(virt, end);
210 }
211
212 static int
213 remap_area_sections(unsigned long virt, unsigned long pfn,
214                     size_t size, const struct mem_type *type)
215 {
216         unsigned long addr = virt, end = virt + size;
217         pmd_t *pmd = pmd_off_k(addr);
218
219         /*
220          * Remove and free any PTE-based mapping, and
221          * sync the current kernel mapping.
222          */
223         unmap_area_sections(virt, size);
224
225         do {
226                 pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
227                 pfn += SZ_1M >> PAGE_SHIFT;
228                 pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
229                 pfn += SZ_1M >> PAGE_SHIFT;
230                 flush_pmd_entry(pmd);
231
232                 addr += PMD_SIZE;
233                 pmd += 2;
234         } while (addr < end);
235
236         return 0;
237 }
238
239 static int
240 remap_area_supersections(unsigned long virt, unsigned long pfn,
241                          size_t size, const struct mem_type *type)
242 {
243         unsigned long addr = virt, end = virt + size;
244         pmd_t *pmd = pmd_off_k(addr);
245
246         /*
247          * Remove and free any PTE-based mapping, and
248          * sync the current kernel mapping.
249          */
250         unmap_area_sections(virt, size);
251         do {
252                 unsigned long super_pmd_val, i;
253
254                 super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
255                                 PMD_SECT_SUPER;
256                 super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
257
258                 for (i = 0; i < 8; i++) {
259                         pmd[0] = __pmd(super_pmd_val);
260                         pmd[1] = __pmd(super_pmd_val);
261                         flush_pmd_entry(pmd);
262
263                         addr += PMD_SIZE;
264                         pmd += 2;
265                 }
266
267                 pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
268         } while (addr < end);
269
270         return 0;
271 }
272 #endif
273
274 static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
275         unsigned long offset, size_t size, unsigned int mtype, void *caller)
276 {
277         const struct mem_type *type;
278         int err;
279         unsigned long addr;
280         struct vm_struct *area;
281         phys_addr_t paddr = __pfn_to_phys(pfn);
282
283 #ifndef CONFIG_ARM_LPAE
284         /*
285          * High mappings must be supersection aligned
286          */
287         if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
288                 return NULL;
289 #endif
290
291         type = get_mem_type(mtype);
292         if (!type)
293                 return NULL;
294
295         /*
296          * Page align the mapping size, taking account of any offset.
297          */
298         size = PAGE_ALIGN(offset + size);
299
300         /*
301          * Try to reuse one of the static mapping whenever possible.
302          */
303         if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
304                 struct static_vm *svm;
305
306                 svm = find_static_vm_paddr(paddr, size, mtype);
307                 if (svm) {
308                         addr = (unsigned long)svm->vm.addr;
309                         addr += paddr - svm->vm.phys_addr;
310                         return (void __iomem *) (offset + addr);
311                 }
312         }
313
314         /*
315          * Don't allow RAM to be mapped with mismatched attributes - this
316          * causes problems with ARMv6+
317          */
318         if (WARN_ON(memblock_is_map_memory(PFN_PHYS(pfn)) &&
319                     mtype != MT_MEMORY_RW))
320                 return NULL;
321
322         area = get_vm_area_caller(size, VM_IOREMAP, caller);
323         if (!area)
324                 return NULL;
325         addr = (unsigned long)area->addr;
326         area->phys_addr = paddr;
327
328 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
329         if (DOMAIN_IO == 0 &&
330             (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
331                cpu_is_xsc3()) && pfn >= 0x100000 &&
332                !((paddr | size | addr) & ~SUPERSECTION_MASK)) {
333                 area->flags |= VM_ARM_SECTION_MAPPING;
334                 err = remap_area_supersections(addr, pfn, size, type);
335         } else if (!((paddr | size | addr) & ~PMD_MASK)) {
336                 area->flags |= VM_ARM_SECTION_MAPPING;
337                 err = remap_area_sections(addr, pfn, size, type);
338         } else
339 #endif
340                 err = ioremap_page_range(addr, addr + size, paddr,
341                                          __pgprot(type->prot_pte));
342
343         if (err) {
344                 vunmap((void *)addr);
345                 return NULL;
346         }
347
348         flush_cache_vmap(addr, addr + size);
349         return (void __iomem *) (offset + addr);
350 }
351
352 void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
353         unsigned int mtype, void *caller)
354 {
355         phys_addr_t last_addr;
356         unsigned long offset = phys_addr & ~PAGE_MASK;
357         unsigned long pfn = __phys_to_pfn(phys_addr);
358
359         /*
360          * Don't allow wraparound or zero size
361          */
362         last_addr = phys_addr + size - 1;
363         if (!size || last_addr < phys_addr)
364                 return NULL;
365
366         return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
367                         caller);
368 }
369
370 /*
371  * Remap an arbitrary physical address space into the kernel virtual
372  * address space. Needed when the kernel wants to access high addresses
373  * directly.
374  *
375  * NOTE! We need to allow non-page-aligned mappings too: we will obviously
376  * have to convert them into an offset in a page-aligned mapping, but the
377  * caller shouldn't need to know that small detail.
378  */
379 void __iomem *
380 __arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
381                   unsigned int mtype)
382 {
383         return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
384                                         __builtin_return_address(0));
385 }
386 EXPORT_SYMBOL(__arm_ioremap_pfn);
387
388 void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
389                                       unsigned int, void *) =
390         __arm_ioremap_caller;
391
392 void __iomem *ioremap(resource_size_t res_cookie, size_t size)
393 {
394         return arch_ioremap_caller(res_cookie, size, MT_DEVICE,
395                                    __builtin_return_address(0));
396 }
397 EXPORT_SYMBOL(ioremap);
398
399 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
400 {
401         return arch_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
402                                    __builtin_return_address(0));
403 }
404 EXPORT_SYMBOL(ioremap_cache);
405
406 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
407 {
408         return arch_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
409                                    __builtin_return_address(0));
410 }
411 EXPORT_SYMBOL(ioremap_wc);
412
413 /*
414  * Remap an arbitrary physical address space into the kernel virtual
415  * address space as memory. Needed when the kernel wants to execute
416  * code in external memory. This is needed for reprogramming source
417  * clocks that would affect normal memory for example. Please see
418  * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
419  */
420 void __iomem *
421 __arm_ioremap_exec(phys_addr_t phys_addr, size_t size, bool cached)
422 {
423         unsigned int mtype;
424
425         if (cached)
426                 mtype = MT_MEMORY_RWX;
427         else
428                 mtype = MT_MEMORY_RWX_NONCACHED;
429
430         return __arm_ioremap_caller(phys_addr, size, mtype,
431                         __builtin_return_address(0));
432 }
433
434 void __arm_iomem_set_ro(void __iomem *ptr, size_t size)
435 {
436         set_memory_ro((unsigned long)ptr, PAGE_ALIGN(size) / PAGE_SIZE);
437 }
438
439 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
440 {
441         return (__force void *)arch_ioremap_caller(phys_addr, size,
442                                                    MT_MEMORY_RW,
443                                                    __builtin_return_address(0));
444 }
445
446 void iounmap(volatile void __iomem *io_addr)
447 {
448         void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
449         struct static_vm *svm;
450
451         /* If this is a static mapping, we must leave it alone */
452         svm = find_static_vm_vaddr(addr);
453         if (svm)
454                 return;
455
456 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
457         {
458                 struct vm_struct *vm;
459
460                 vm = find_vm_area(addr);
461
462                 /*
463                  * If this is a section based mapping we need to handle it
464                  * specially as the VM subsystem does not know how to handle
465                  * such a beast.
466                  */
467                 if (vm && (vm->flags & VM_ARM_SECTION_MAPPING))
468                         unmap_area_sections((unsigned long)vm->addr, vm->size);
469         }
470 #endif
471
472         vunmap(addr);
473 }
474 EXPORT_SYMBOL(iounmap);
475
476 #if defined(CONFIG_PCI) || IS_ENABLED(CONFIG_PCMCIA)
477 static int pci_ioremap_mem_type = MT_DEVICE;
478
479 void pci_ioremap_set_mem_type(int mem_type)
480 {
481         pci_ioremap_mem_type = mem_type;
482 }
483
484 int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
485 {
486         unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
487
488         if (!(res->flags & IORESOURCE_IO))
489                 return -EINVAL;
490
491         if (res->end > IO_SPACE_LIMIT)
492                 return -EINVAL;
493
494         return vmap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
495                                __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte));
496 }
497 EXPORT_SYMBOL(pci_remap_iospace);
498
499 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
500 {
501         return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
502                                    __builtin_return_address(0));
503 }
504 EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
505 #endif
506
507 /*
508  * Must be called after early_fixmap_init
509  */
510 void __init early_ioremap_init(void)
511 {
512         early_ioremap_setup();
513 }
514
515 bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
516                                  unsigned long flags)
517 {
518         unsigned long pfn = PHYS_PFN(offset);
519
520         return memblock_is_map_memory(pfn);
521 }
This page took 0.058667 seconds and 4 git commands to generate.