diff options
Diffstat (limited to 'mm/nommu.c')
| -rw-r--r-- | mm/nommu.c | 254 |
1 files changed, 167 insertions, 87 deletions
diff --git a/mm/nommu.c b/mm/nommu.c index 5ec8f44e7ce9..b624acec6d2e 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -42,18 +42,11 @@ #include <asm/mmu_context.h> #include "internal.h" -void *high_memory; -EXPORT_SYMBOL(high_memory); -struct page *mem_map; -unsigned long max_mapnr; -EXPORT_SYMBOL(max_mapnr); unsigned long highest_memmap_pfn; -int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; int heap_stack_gap = 0; atomic_long_t mmap_pages_allocated; -EXPORT_SYMBOL(mem_map); /* list of mapped, potentially shareable regions */ static struct kmem_cache *vm_region_jar; @@ -110,55 +103,39 @@ unsigned int kobjsize(const void *objp) return page_size(page); } -/** - * follow_pfn - look up PFN at a user virtual address - * @vma: memory mapping - * @address: user virtual address - * @pfn: location to store found PFN - * - * Only IO mappings and raw PFN mappings are allowed. - * - * Returns zero and the pfn at @pfn on success, -ve otherwise. - */ -int follow_pfn(struct vm_area_struct *vma, unsigned long address, - unsigned long *pfn) -{ - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) - return -EINVAL; - - *pfn = address >> PAGE_SHIFT; - return 0; -} -EXPORT_SYMBOL(follow_pfn); - void vfree(const void *addr) { kfree(addr); } EXPORT_SYMBOL(vfree); -void *__vmalloc(unsigned long size, gfp_t gfp_mask) +void *__vmalloc_noprof(unsigned long size, gfp_t gfp_mask) { /* * You can't specify __GFP_HIGHMEM with kmalloc() since kmalloc() * returns only a logical address. */ - return kmalloc(size, (gfp_mask | __GFP_COMP) & ~__GFP_HIGHMEM); + return kmalloc_noprof(size, (gfp_mask | __GFP_COMP) & ~__GFP_HIGHMEM); } -EXPORT_SYMBOL(__vmalloc); +EXPORT_SYMBOL(__vmalloc_noprof); -void *__vmalloc_node_range(unsigned long size, unsigned long align, +void *vrealloc_noprof(const void *p, size_t size, gfp_t flags) +{ + return krealloc_noprof(p, size, (flags | __GFP_COMP) & ~__GFP_HIGHMEM); +} + +void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align, unsigned long start, unsigned long end, gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags, int node, const void *caller) { - return __vmalloc(size, gfp_mask); + return __vmalloc_noprof(size, gfp_mask); } -void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, +void *__vmalloc_node_noprof(unsigned long size, unsigned long align, gfp_t gfp_mask, int node, const void *caller) { - return __vmalloc(size, gfp_mask); + return __vmalloc_noprof(size, gfp_mask); } static void *__vmalloc_user_flags(unsigned long size, gfp_t flags) @@ -179,11 +156,11 @@ static void *__vmalloc_user_flags(unsigned long size, gfp_t flags) return ret; } -void *vmalloc_user(unsigned long size) +void *vmalloc_user_noprof(unsigned long size) { return __vmalloc_user_flags(size, GFP_KERNEL | __GFP_ZERO); } -EXPORT_SYMBOL(vmalloc_user); +EXPORT_SYMBOL(vmalloc_user_noprof); struct page *vmalloc_to_page(const void *addr) { @@ -217,13 +194,29 @@ long vread_iter(struct iov_iter *iter, const char *addr, size_t count) * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ -void *vmalloc(unsigned long size) +void *vmalloc_noprof(unsigned long size) { - return __vmalloc(size, GFP_KERNEL); + return __vmalloc_noprof(size, GFP_KERNEL); } -EXPORT_SYMBOL(vmalloc); +EXPORT_SYMBOL(vmalloc_noprof); -void *vmalloc_huge(unsigned long size, gfp_t gfp_mask) __weak __alias(__vmalloc); +/* + * vmalloc_huge_node - allocate virtually contiguous memory, on a node + * + * @size: allocation size + * @gfp_mask: flags for the page level allocator + * @node: node to use for allocation or NUMA_NO_NODE + * + * Allocate enough pages to cover @size from the page level + * allocator and map them into contiguous kernel virtual space. + * + * Due to NOMMU implications the node argument and HUGE page attribute is + * ignored. + */ +void *vmalloc_huge_node_noprof(unsigned long size, gfp_t gfp_mask, int node) +{ + return __vmalloc_noprof(size, gfp_mask); +} /* * vzalloc - allocate virtually contiguous memory with zero fill @@ -237,11 +230,11 @@ void *vmalloc_huge(unsigned long size, gfp_t gfp_mask) __weak __alias(__vmalloc) * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ -void *vzalloc(unsigned long size) +void *vzalloc_noprof(unsigned long size) { - return __vmalloc(size, GFP_KERNEL | __GFP_ZERO); + return __vmalloc_noprof(size, GFP_KERNEL | __GFP_ZERO); } -EXPORT_SYMBOL(vzalloc); +EXPORT_SYMBOL(vzalloc_noprof); /** * vmalloc_node - allocate memory on a specific node @@ -254,11 +247,11 @@ EXPORT_SYMBOL(vzalloc); * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ -void *vmalloc_node(unsigned long size, int node) +void *vmalloc_node_noprof(unsigned long size, int node) { - return vmalloc(size); + return vmalloc_noprof(size); } -EXPORT_SYMBOL(vmalloc_node); +EXPORT_SYMBOL(vmalloc_node_noprof); /** * vzalloc_node - allocate memory on a specific node with zero fill @@ -272,11 +265,11 @@ EXPORT_SYMBOL(vmalloc_node); * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ -void *vzalloc_node(unsigned long size, int node) +void *vzalloc_node_noprof(unsigned long size, int node) { - return vzalloc(size); + return vzalloc_noprof(size); } -EXPORT_SYMBOL(vzalloc_node); +EXPORT_SYMBOL(vzalloc_node_noprof); /** * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) @@ -285,11 +278,11 @@ EXPORT_SYMBOL(vzalloc_node); * Allocate enough 32bit PA addressable pages to cover @size from the * page level allocator and map them into contiguous kernel virtual space. */ -void *vmalloc_32(unsigned long size) +void *vmalloc_32_noprof(unsigned long size) { - return __vmalloc(size, GFP_KERNEL); + return __vmalloc_noprof(size, GFP_KERNEL); } -EXPORT_SYMBOL(vmalloc_32); +EXPORT_SYMBOL(vmalloc_32_noprof); /** * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory @@ -301,15 +294,15 @@ EXPORT_SYMBOL(vmalloc_32); * VM_USERMAP is set on the corresponding VMA so that subsequent calls to * remap_vmalloc_range() are permissible. */ -void *vmalloc_32_user(unsigned long size) +void *vmalloc_32_user_noprof(unsigned long size) { /* * We'll have to sort out the ZONE_DMA bits for 64-bit, * but for now this can simply use vmalloc_user() directly. */ - return vmalloc_user(size); + return vmalloc_user_noprof(size); } -EXPORT_SYMBOL(vmalloc_32_user); +EXPORT_SYMBOL(vmalloc_32_user_noprof); void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot) { @@ -355,6 +348,13 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, } EXPORT_SYMBOL(vm_insert_page); +int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr, + struct page **pages, unsigned long *num) +{ + return -EINVAL; +} +EXPORT_SYMBOL(vm_insert_pages); + int vm_map_pages(struct vm_area_struct *vma, struct page **pages, unsigned long num) { @@ -401,8 +401,22 @@ SYSCALL_DEFINE1(brk, unsigned long, brk) return mm->brk = brk; } +static int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; + +static const struct ctl_table nommu_table[] = { + { + .procname = "nr_trim_pages", + .data = &sysctl_nr_trim_pages, + .maxlen = sizeof(sysctl_nr_trim_pages), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + }, +}; + /* - * initialise the percpu counter for VM and region record slabs + * initialise the percpu counter for VM and region record slabs, initialise VMA + * state. */ void __init mmap_init(void) { @@ -411,6 +425,8 @@ void __init mmap_init(void) ret = percpu_counter_init(&vm_committed_as, 0, GFP_KERNEL); VM_BUG_ON(ret); vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC|SLAB_ACCOUNT); + register_sysctl_init("vm", nommu_table); + vma_state_init(); } /* @@ -582,7 +598,7 @@ static int delete_vma_from_mm(struct vm_area_struct *vma) VMA_ITERATOR(vmi, vma->vm_mm, vma->vm_start); vma_iter_config(&vmi, vma->vm_start, vma->vm_end); - if (vma_iter_prealloc(&vmi, vma)) { + if (vma_iter_prealloc(&vmi, NULL)) { pr_warn("Allocation of vma tree for process %d failed\n", current->pid); return -ENOMEM; @@ -598,8 +614,7 @@ static int delete_vma_from_mm(struct vm_area_struct *vma) */ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) { - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); + vma_close(vma); if (vma->vm_file) fput(vma->vm_file); put_nommu_region(vma->vm_region); @@ -630,22 +645,6 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) EXPORT_SYMBOL(find_vma); /* - * At least xtensa ends up having protection faults even with no - * MMU.. No stack expansion, at least. - */ -struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm, - unsigned long addr, struct pt_regs *regs) -{ - struct vm_area_struct *vma; - - mmap_read_lock(mm); - vma = vma_lookup(mm, addr); - if (!vma) - mmap_read_unlock(mm); - return vma; -} - -/* * expand a stack to a given address * - not supported under NOMMU conditions */ @@ -852,7 +851,7 @@ static unsigned long determine_vm_flags(struct file *file, { unsigned long vm_flags; - vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(flags); + vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(file, flags); if (!file) { /* @@ -894,7 +893,7 @@ static int do_mmap_shared_file(struct vm_area_struct *vma) { int ret; - ret = call_mmap(vma->vm_file, vma); + ret = mmap_file(vma->vm_file, vma); if (ret == 0) { vma->vm_region->vm_top = vma->vm_region->vm_end; return 0; @@ -927,7 +926,7 @@ static int do_mmap_private(struct vm_area_struct *vma, * happy. */ if (capabilities & NOMMU_MAP_DIRECT) { - ret = call_mmap(vma->vm_file, vma); + ret = mmap_file(vma->vm_file, vma); /* shouldn't return success if we're not sharing */ if (WARN_ON_ONCE(!is_nommu_shared_mapping(vma->vm_flags))) ret = -ENOSYS; @@ -1201,7 +1200,7 @@ share: setup_vma_to_mm(vma, current->mm); current->mm->map_count++; /* add the VMA to the tree */ - vma_iter_store(&vmi, vma); + vma_iter_store_new(&vmi, vma); /* we flush the region from the icache only when the first executable * mapping of it is made */ @@ -1366,7 +1365,7 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, setup_vma_to_mm(vma, mm); setup_vma_to_mm(new, mm); - vma_iter_store(vmi, new); + vma_iter_store_new(vmi, new); mm->map_count++; return 0; @@ -1587,12 +1586,6 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, return ret; } -struct page *follow_page(struct vm_area_struct *vma, unsigned long address, - unsigned int foll_flags) -{ - return NULL; -} - int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t prot) { @@ -1717,6 +1710,85 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in } EXPORT_SYMBOL_GPL(access_process_vm); +#ifdef CONFIG_BPF_SYSCALL +/* + * Copy a string from another process's address space as given in mm. + * If there is any error return -EFAULT. + */ +static int __copy_remote_vm_str(struct mm_struct *mm, unsigned long addr, + void *buf, int len) +{ + unsigned long addr_end; + struct vm_area_struct *vma; + int ret = -EFAULT; + + *(char *)buf = '\0'; + + if (mmap_read_lock_killable(mm)) + return ret; + + /* the access must start within one of the target process's mappings */ + vma = find_vma(mm, addr); + if (!vma) + goto out; + + if (check_add_overflow(addr, len, &addr_end)) + goto out; + + /* don't overrun this mapping */ + if (addr_end > vma->vm_end) + len = vma->vm_end - addr; + + /* only read mappings where it is permitted */ + if (vma->vm_flags & VM_MAYREAD) { + ret = strscpy(buf, (char *)addr, len); + if (ret < 0) + ret = len - 1; + } + +out: + mmap_read_unlock(mm); + return ret; +} + +/** + * copy_remote_vm_str - copy a string from another process's address space. + * @tsk: the task of the target address space + * @addr: start address to read from + * @buf: destination buffer + * @len: number of bytes to copy + * @gup_flags: flags modifying lookup behaviour (unused) + * + * The caller must hold a reference on @mm. + * + * Return: number of bytes copied from @addr (source) to @buf (destination); + * not including the trailing NUL. Always guaranteed to leave NUL-terminated + * buffer. On any error, return -EFAULT. + */ +int copy_remote_vm_str(struct task_struct *tsk, unsigned long addr, + void *buf, int len, unsigned int gup_flags) +{ + struct mm_struct *mm; + int ret; + + if (unlikely(len == 0)) + return 0; + + mm = get_task_mm(tsk); + if (!mm) { + *(char *)buf = '\0'; + return -EFAULT; + } + + ret = __copy_remote_vm_str(mm, addr, buf, len); + + mmput(mm); + + return ret; +} +EXPORT_SYMBOL_GPL(copy_remote_vm_str); +#endif /* CONFIG_BPF_SYSCALL */ + /** * nommu_shrink_inode_mappings - Shrink the shared mappings on an inode * @inode: The inode to check @@ -1820,3 +1892,11 @@ static int __meminit init_admin_reserve(void) return 0; } subsys_initcall(init_admin_reserve); + +int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) +{ + mmap_write_lock(oldmm); + dup_mm_exe_file(mm, oldmm); + mmap_write_unlock(oldmm); + return 0; +} |