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mm/nommu.c
48.3 KB
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/* * linux/mm/nommu.c * * Replacement code for mm functions to support CPU's that don't * have any form of memory management unit (thus no virtual memory). * * See Documentation/nommu-mmap.txt * |
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* Copyright (c) 2004-2008 David Howells <dhowells@redhat.com> |
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* Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com> * Copyright (c) 2000-2001 D Jeff Dionne <jeff@uClinux.org> * Copyright (c) 2002 Greg Ungerer <gerg@snapgear.com> |
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* Copyright (c) 2007-2009 Paul Mundt <lethal@linux-sh.org> |
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*/ |
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#include <linux/module.h> |
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#include <linux/mm.h> #include <linux/mman.h> #include <linux/swap.h> #include <linux/file.h> #include <linux/highmem.h> #include <linux/pagemap.h> #include <linux/slab.h> #include <linux/vmalloc.h> |
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#include <linux/tracehook.h> |
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#include <linux/blkdev.h> #include <linux/backing-dev.h> #include <linux/mount.h> #include <linux/personality.h> #include <linux/security.h> #include <linux/syscalls.h> #include <asm/uaccess.h> #include <asm/tlb.h> #include <asm/tlbflush.h> |
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#include <asm/mmu_context.h> |
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#include "internal.h" |
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#if 0 #define kenter(FMT, ...) \ printk(KERN_DEBUG "==> %s("FMT") ", __func__, ##__VA_ARGS__) #define kleave(FMT, ...) \ printk(KERN_DEBUG "<== %s()"FMT" ", __func__, ##__VA_ARGS__) #define kdebug(FMT, ...) \ printk(KERN_DEBUG "xxx" FMT"yyy ", ##__VA_ARGS__) #else #define kenter(FMT, ...) \ no_printk(KERN_DEBUG "==> %s("FMT") ", __func__, ##__VA_ARGS__) #define kleave(FMT, ...) \ no_printk(KERN_DEBUG "<== %s()"FMT" ", __func__, ##__VA_ARGS__) #define kdebug(FMT, ...) \ no_printk(KERN_DEBUG FMT" ", ##__VA_ARGS__) #endif |
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void *high_memory; struct page *mem_map; unsigned long max_mapnr; unsigned long num_physpages; |
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unsigned long highest_memmap_pfn; |
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struct percpu_counter vm_committed_as; |
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int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */ int sysctl_overcommit_ratio = 50; /* default is 50% */ int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT; |
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int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; |
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int heap_stack_gap = 0; |
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atomic_long_t mmap_pages_allocated; |
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|
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EXPORT_SYMBOL(mem_map); |
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EXPORT_SYMBOL(num_physpages); |
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|
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/* list of mapped, potentially shareable regions */ static struct kmem_cache *vm_region_jar; struct rb_root nommu_region_tree = RB_ROOT; DECLARE_RWSEM(nommu_region_sem); |
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|
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const struct vm_operations_struct generic_file_vm_ops = { |
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}; /* |
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* Return the total memory allocated for this pointer, not * just what the caller asked for. * * Doesn't have to be accurate, i.e. may have races. */ unsigned int kobjsize(const void *objp) { struct page *page; |
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/* * If the object we have should not have ksize performed on it, * return size of 0 */ |
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if (!objp || !virt_addr_valid(objp)) |
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return 0; page = virt_to_head_page(objp); |
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/* * If the allocator sets PageSlab, we know the pointer came from * kmalloc(). */ |
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if (PageSlab(page)) return ksize(objp); |
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/* |
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* If it's not a compound page, see if we have a matching VMA * region. This test is intentionally done in reverse order, * so if there's no VMA, we still fall through and hand back * PAGE_SIZE for 0-order pages. */ if (!PageCompound(page)) { struct vm_area_struct *vma; vma = find_vma(current->mm, (unsigned long)objp); if (vma) return vma->vm_end - vma->vm_start; } /* |
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* The ksize() function is only guaranteed to work for pointers |
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* returned by kmalloc(). So handle arbitrary pointers here. |
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*/ |
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return PAGE_SIZE << compound_order(page); |
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} |
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int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, |
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unsigned long start, int nr_pages, unsigned int foll_flags, |
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struct page **pages, struct vm_area_struct **vmas) |
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{ |
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struct vm_area_struct *vma; |
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unsigned long vm_flags; int i; /* calculate required read or write permissions. |
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* If FOLL_FORCE is set, we only require the "MAY" flags. |
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*/ |
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vm_flags = (foll_flags & FOLL_WRITE) ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD); vm_flags &= (foll_flags & FOLL_FORCE) ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE); |
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|
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for (i = 0; i < nr_pages; i++) { |
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vma = find_vma(mm, start); |
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if (!vma) goto finish_or_fault; /* protect what we can, including chardevs */ |
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if ((vma->vm_flags & (VM_IO | VM_PFNMAP)) || !(vm_flags & vma->vm_flags)) |
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goto finish_or_fault; |
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|
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if (pages) { pages[i] = virt_to_page(start); if (pages[i]) page_cache_get(pages[i]); } if (vmas) |
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vmas[i] = vma; |
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start = (start + PAGE_SIZE) & PAGE_MASK; |
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} |
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return i; finish_or_fault: return i ? : -EFAULT; |
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} |
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|
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/* * get a list of pages in an address range belonging to the specified process * and indicate the VMA that covers each page * - this is potentially dodgy as we may end incrementing the page count of a * slab page or a secondary page from a compound page * - don't permit access to VMAs that don't support it, such as I/O mappings */ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, |
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unsigned long start, int nr_pages, int write, int force, |
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struct page **pages, struct vm_area_struct **vmas) { int flags = 0; if (write) |
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flags |= FOLL_WRITE; |
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if (force) |
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flags |= FOLL_FORCE; |
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|
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return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas); |
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} |
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EXPORT_SYMBOL(get_user_pages); |
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/** * 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); |
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DEFINE_RWLOCK(vmlist_lock); struct vm_struct *vmlist; |
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void vfree(const void *addr) |
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{ kfree(addr); } |
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EXPORT_SYMBOL(vfree); |
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|
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void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) |
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{ /* |
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* You can't specify __GFP_HIGHMEM with kmalloc() since kmalloc() * returns only a logical address. |
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*/ |
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return kmalloc(size, (gfp_mask | __GFP_COMP) & ~__GFP_HIGHMEM); |
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} |
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EXPORT_SYMBOL(__vmalloc); |
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|
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void *vmalloc_user(unsigned long size) { void *ret; ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); if (ret) { struct vm_area_struct *vma; down_write(¤t->mm->mmap_sem); vma = find_vma(current->mm, (unsigned long)ret); if (vma) vma->vm_flags |= VM_USERMAP; up_write(¤t->mm->mmap_sem); } return ret; } EXPORT_SYMBOL(vmalloc_user); |
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struct page *vmalloc_to_page(const void *addr) |
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{ return virt_to_page(addr); } |
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EXPORT_SYMBOL(vmalloc_to_page); |
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|
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unsigned long vmalloc_to_pfn(const void *addr) |
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{ return page_to_pfn(virt_to_page(addr)); } |
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EXPORT_SYMBOL(vmalloc_to_pfn); |
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long vread(char *buf, char *addr, unsigned long count) { memcpy(buf, addr, count); return count; } long vwrite(char *buf, char *addr, unsigned long count) { /* Don't allow overflow */ if ((unsigned long) addr + count < count) count = -(unsigned long) addr; memcpy(addr, buf, count); return(count); } /* * vmalloc - allocate virtually continguos memory * * @size: allocation size * * Allocate enough pages to cover @size from the page level * allocator and map them into continguos kernel virtual space. * |
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* For tight control over page level allocator and protection flags |
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* use __vmalloc() instead. */ void *vmalloc(unsigned long size) { return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL); } |
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EXPORT_SYMBOL(vmalloc); void *vmalloc_node(unsigned long size, int node) { return vmalloc(size); } EXPORT_SYMBOL(vmalloc_node); |
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#ifndef PAGE_KERNEL_EXEC # define PAGE_KERNEL_EXEC PAGE_KERNEL #endif /** * vmalloc_exec - allocate virtually contiguous, executable memory * @size: allocation size * * Kernel-internal function to allocate enough pages to cover @size * the page level allocator and map them into contiguous and * executable kernel virtual space. * * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ void *vmalloc_exec(unsigned long size) { return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC); } |
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/** * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) |
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* @size: allocation size * * Allocate enough 32bit PA addressable pages to cover @size from the * page level allocator and map them into continguos kernel virtual space. */ void *vmalloc_32(unsigned long size) { return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL); } |
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EXPORT_SYMBOL(vmalloc_32); /** * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory * @size: allocation size * * The resulting memory area is 32bit addressable and zeroed so it can be * mapped to userspace without leaking data. |
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* * VM_USERMAP is set on the corresponding VMA so that subsequent calls to * remap_vmalloc_range() are permissible. |
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*/ void *vmalloc_32_user(unsigned long size) { |
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/* * 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); |
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} EXPORT_SYMBOL(vmalloc_32_user); |
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void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot) { BUG(); return NULL; } |
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EXPORT_SYMBOL(vmap); |
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|
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void vunmap(const void *addr) |
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{ BUG(); } |
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EXPORT_SYMBOL(vunmap); |
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|
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void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot) { BUG(); return NULL; } EXPORT_SYMBOL(vm_map_ram); void vm_unmap_ram(const void *mem, unsigned int count) { BUG(); } EXPORT_SYMBOL(vm_unmap_ram); void vm_unmap_aliases(void) { } EXPORT_SYMBOL_GPL(vm_unmap_aliases); |
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/* |
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* Implement a stub for vmalloc_sync_all() if the architecture chose not to * have one. */ void __attribute__((weak)) vmalloc_sync_all(void) { } |
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int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *page) { return -EINVAL; } EXPORT_SYMBOL(vm_insert_page); |
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/* |
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* sys_brk() for the most part doesn't need the global kernel * lock, except when an application is doing something nasty * like trying to un-brk an area that has already been mapped * to a regular file. in this case, the unmapping will need * to invoke file system routines that need the global lock. */ |
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SYSCALL_DEFINE1(brk, unsigned long, brk) |
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{ struct mm_struct *mm = current->mm; if (brk < mm->start_brk || brk > mm->context.end_brk) return mm->brk; if (mm->brk == brk) return mm->brk; /* * Always allow shrinking brk */ if (brk <= mm->brk) { mm->brk = brk; return brk; } /* * Ok, looks good - let it rip. */ |
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flush_icache_range(mm->brk, brk); |
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return mm->brk = brk; } |
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/* * initialise the VMA and region record slabs */ void __init mmap_init(void) |
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{ |
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int ret; ret = percpu_counter_init(&vm_committed_as, 0); VM_BUG_ON(ret); |
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vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC); |
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} |
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|
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/* |
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* validate the region tree * - the caller must hold the region lock |
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*/ |
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#ifdef CONFIG_DEBUG_NOMMU_REGIONS static noinline void validate_nommu_regions(void) |
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{ |
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struct vm_region *region, *last; struct rb_node *p, *lastp; |
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|
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lastp = rb_first(&nommu_region_tree); if (!lastp) return; last = rb_entry(lastp, struct vm_region, vm_rb); |
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BUG_ON(unlikely(last->vm_end <= last->vm_start)); BUG_ON(unlikely(last->vm_top < last->vm_end)); |
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while ((p = rb_next(lastp))) { region = rb_entry(p, struct vm_region, vm_rb); last = rb_entry(lastp, struct vm_region, vm_rb); |
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BUG_ON(unlikely(region->vm_end <= region->vm_start)); BUG_ON(unlikely(region->vm_top < region->vm_end)); BUG_ON(unlikely(region->vm_start < last->vm_top)); |
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|
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lastp = p; } |
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} |
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#else |
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static void validate_nommu_regions(void) { } |
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#endif |
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/* |
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* add a region into the global tree |
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*/ |
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static void add_nommu_region(struct vm_region *region) |
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{ |
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struct vm_region *pregion; struct rb_node **p, *parent; |
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|
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validate_nommu_regions(); |
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parent = NULL; p = &nommu_region_tree.rb_node; while (*p) { parent = *p; pregion = rb_entry(parent, struct vm_region, vm_rb); if (region->vm_start < pregion->vm_start) p = &(*p)->rb_left; else if (region->vm_start > pregion->vm_start) p = &(*p)->rb_right; else if (pregion == region) return; else BUG(); |
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} |
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rb_link_node(®ion->vm_rb, parent, p); rb_insert_color(®ion->vm_rb, &nommu_region_tree); |
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|
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validate_nommu_regions(); |
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} |
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/* |
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* delete a region from the global tree |
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*/ |
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503 |
static void delete_nommu_region(struct vm_region *region) |
930e652a2 [PATCH] NOMMU: Ma... |
504 |
{ |
8feae1311 NOMMU: Make VMAs ... |
505 |
BUG_ON(!nommu_region_tree.rb_node); |
930e652a2 [PATCH] NOMMU: Ma... |
506 |
|
8feae1311 NOMMU: Make VMAs ... |
507 508 509 |
validate_nommu_regions(); rb_erase(®ion->vm_rb, &nommu_region_tree); validate_nommu_regions(); |
57c8f63e8 nommu: stub expan... |
510 |
} |
930e652a2 [PATCH] NOMMU: Ma... |
511 |
/* |
8feae1311 NOMMU: Make VMAs ... |
512 |
* free a contiguous series of pages |
6fa5f80bc [PATCH] NOMMU: Ma... |
513 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
514 |
static void free_page_series(unsigned long from, unsigned long to) |
6fa5f80bc [PATCH] NOMMU: Ma... |
515 |
{ |
8feae1311 NOMMU: Make VMAs ... |
516 517 518 519 |
for (; from < to; from += PAGE_SIZE) { struct page *page = virt_to_page(from); kdebug("- free %lx", from); |
33e5d7697 nommu: fix a numb... |
520 |
atomic_long_dec(&mmap_pages_allocated); |
8feae1311 NOMMU: Make VMAs ... |
521 |
if (page_count(page) != 1) |
33e5d7697 nommu: fix a numb... |
522 523 |
kdebug("free page %p: refcount not one: %d", page, page_count(page)); |
8feae1311 NOMMU: Make VMAs ... |
524 |
put_page(page); |
6fa5f80bc [PATCH] NOMMU: Ma... |
525 |
} |
6fa5f80bc [PATCH] NOMMU: Ma... |
526 527 528 |
} /* |
8feae1311 NOMMU: Make VMAs ... |
529 |
* release a reference to a region |
33e5d7697 nommu: fix a numb... |
530 |
* - the caller must hold the region semaphore for writing, which this releases |
dd8632a12 NOMMU: Make mmap ... |
531 |
* - the region may not have been added to the tree yet, in which case vm_top |
8feae1311 NOMMU: Make VMAs ... |
532 |
* will equal vm_start |
3034097a5 [PATCH] NOMMU: Or... |
533 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
534 535 |
static void __put_nommu_region(struct vm_region *region) __releases(nommu_region_sem) |
1da177e4c Linux-2.6.12-rc2 |
536 |
{ |
1e2ae599d nommu: struct vm_... |
537 |
kenter("%p{%d}", region, region->vm_usage); |
1da177e4c Linux-2.6.12-rc2 |
538 |
|
8feae1311 NOMMU: Make VMAs ... |
539 |
BUG_ON(!nommu_region_tree.rb_node); |
1da177e4c Linux-2.6.12-rc2 |
540 |
|
1e2ae599d nommu: struct vm_... |
541 |
if (--region->vm_usage == 0) { |
dd8632a12 NOMMU: Make mmap ... |
542 |
if (region->vm_top > region->vm_start) |
8feae1311 NOMMU: Make VMAs ... |
543 544 545 546 547 548 549 550 551 552 |
delete_nommu_region(region); up_write(&nommu_region_sem); if (region->vm_file) fput(region->vm_file); /* IO memory and memory shared directly out of the pagecache * from ramfs/tmpfs mustn't be released here */ if (region->vm_flags & VM_MAPPED_COPY) { kdebug("free series"); |
dd8632a12 NOMMU: Make mmap ... |
553 |
free_page_series(region->vm_start, region->vm_top); |
8feae1311 NOMMU: Make VMAs ... |
554 555 556 557 |
} kmem_cache_free(vm_region_jar, region); } else { up_write(&nommu_region_sem); |
1da177e4c Linux-2.6.12-rc2 |
558 |
} |
8feae1311 NOMMU: Make VMAs ... |
559 |
} |
1da177e4c Linux-2.6.12-rc2 |
560 |
|
8feae1311 NOMMU: Make VMAs ... |
561 562 563 564 565 566 567 |
/* * release a reference to a region */ static void put_nommu_region(struct vm_region *region) { down_write(&nommu_region_sem); __put_nommu_region(region); |
1da177e4c Linux-2.6.12-rc2 |
568 |
} |
3034097a5 [PATCH] NOMMU: Or... |
569 |
/* |
eb8cdec4a nommu: add suppor... |
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 |
* update protection on a vma */ static void protect_vma(struct vm_area_struct *vma, unsigned long flags) { #ifdef CONFIG_MPU struct mm_struct *mm = vma->vm_mm; long start = vma->vm_start & PAGE_MASK; while (start < vma->vm_end) { protect_page(mm, start, flags); start += PAGE_SIZE; } update_protections(mm); #endif } /* |
8feae1311 NOMMU: Make VMAs ... |
586 587 588 589 |
* add a VMA into a process's mm_struct in the appropriate place in the list * and tree and add to the address space's page tree also if not an anonymous * page * - should be called with mm->mmap_sem held writelocked |
3034097a5 [PATCH] NOMMU: Or... |
590 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
591 |
static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) |
1da177e4c Linux-2.6.12-rc2 |
592 |
{ |
297c5eee3 mm: make the vma ... |
593 |
struct vm_area_struct *pvma, **pp, *next; |
1da177e4c Linux-2.6.12-rc2 |
594 |
struct address_space *mapping; |
8feae1311 NOMMU: Make VMAs ... |
595 596 597 598 599 600 601 602 |
struct rb_node **p, *parent; kenter(",%p", vma); BUG_ON(!vma->vm_region); mm->map_count++; vma->vm_mm = mm; |
1da177e4c Linux-2.6.12-rc2 |
603 |
|
eb8cdec4a nommu: add suppor... |
604 |
protect_vma(vma, vma->vm_flags); |
1da177e4c Linux-2.6.12-rc2 |
605 606 607 608 609 610 611 612 |
/* add the VMA to the mapping */ if (vma->vm_file) { mapping = vma->vm_file->f_mapping; flush_dcache_mmap_lock(mapping); vma_prio_tree_insert(vma, &mapping->i_mmap); flush_dcache_mmap_unlock(mapping); } |
8feae1311 NOMMU: Make VMAs ... |
613 614 615 |
/* add the VMA to the tree */ parent = NULL; p = &mm->mm_rb.rb_node; |
1da177e4c Linux-2.6.12-rc2 |
616 617 618 |
while (*p) { parent = *p; pvma = rb_entry(parent, struct vm_area_struct, vm_rb); |
8feae1311 NOMMU: Make VMAs ... |
619 620 621 |
/* sort by: start addr, end addr, VMA struct addr in that order * (the latter is necessary as we may get identical VMAs) */ if (vma->vm_start < pvma->vm_start) |
1da177e4c Linux-2.6.12-rc2 |
622 |
p = &(*p)->rb_left; |
8feae1311 NOMMU: Make VMAs ... |
623 |
else if (vma->vm_start > pvma->vm_start) |
1da177e4c Linux-2.6.12-rc2 |
624 |
p = &(*p)->rb_right; |
8feae1311 NOMMU: Make VMAs ... |
625 626 627 628 629 630 631 632 633 634 |
else if (vma->vm_end < pvma->vm_end) p = &(*p)->rb_left; else if (vma->vm_end > pvma->vm_end) p = &(*p)->rb_right; else if (vma < pvma) p = &(*p)->rb_left; else if (vma > pvma) p = &(*p)->rb_right; else BUG(); |
1da177e4c Linux-2.6.12-rc2 |
635 636 637 |
} rb_link_node(&vma->vm_rb, parent, p); |
8feae1311 NOMMU: Make VMAs ... |
638 639 640 641 642 643 644 645 646 647 648 |
rb_insert_color(&vma->vm_rb, &mm->mm_rb); /* add VMA to the VMA list also */ for (pp = &mm->mmap; (pvma = *pp); pp = &(*pp)->vm_next) { if (pvma->vm_start > vma->vm_start) break; if (pvma->vm_start < vma->vm_start) continue; if (pvma->vm_end < vma->vm_end) break; } |
297c5eee3 mm: make the vma ... |
649 |
next = *pp; |
8feae1311 NOMMU: Make VMAs ... |
650 |
*pp = vma; |
297c5eee3 mm: make the vma ... |
651 652 653 |
vma->vm_next = next; if (next) next->vm_prev = vma; |
1da177e4c Linux-2.6.12-rc2 |
654 |
} |
3034097a5 [PATCH] NOMMU: Or... |
655 |
/* |
8feae1311 NOMMU: Make VMAs ... |
656 |
* delete a VMA from its owning mm_struct and address space |
3034097a5 [PATCH] NOMMU: Or... |
657 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
658 |
static void delete_vma_from_mm(struct vm_area_struct *vma) |
1da177e4c Linux-2.6.12-rc2 |
659 |
{ |
8feae1311 NOMMU: Make VMAs ... |
660 |
struct vm_area_struct **pp; |
1da177e4c Linux-2.6.12-rc2 |
661 |
struct address_space *mapping; |
8feae1311 NOMMU: Make VMAs ... |
662 663 664 |
struct mm_struct *mm = vma->vm_mm; kenter("%p", vma); |
eb8cdec4a nommu: add suppor... |
665 |
protect_vma(vma, 0); |
8feae1311 NOMMU: Make VMAs ... |
666 667 668 |
mm->map_count--; if (mm->mmap_cache == vma) mm->mmap_cache = NULL; |
1da177e4c Linux-2.6.12-rc2 |
669 670 671 672 673 674 675 676 677 |
/* remove the VMA from the mapping */ if (vma->vm_file) { mapping = vma->vm_file->f_mapping; flush_dcache_mmap_lock(mapping); vma_prio_tree_remove(vma, &mapping->i_mmap); flush_dcache_mmap_unlock(mapping); } |
8feae1311 NOMMU: Make VMAs ... |
678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 |
/* remove from the MM's tree and list */ rb_erase(&vma->vm_rb, &mm->mm_rb); for (pp = &mm->mmap; *pp; pp = &(*pp)->vm_next) { if (*pp == vma) { *pp = vma->vm_next; break; } } vma->vm_mm = NULL; } /* * destroy a VMA record */ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) { kenter("%p", vma); if (vma->vm_ops && vma->vm_ops->close) vma->vm_ops->close(vma); if (vma->vm_file) { fput(vma->vm_file); if (vma->vm_flags & VM_EXECUTABLE) removed_exe_file_vma(mm); } put_nommu_region(vma->vm_region); kmem_cache_free(vm_area_cachep, vma); } /* * look up the first VMA in which addr resides, NULL if none * - should be called with mm->mmap_sem at least held readlocked */ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) { struct vm_area_struct *vma; struct rb_node *n = mm->mm_rb.rb_node; /* check the cache first */ vma = mm->mmap_cache; if (vma && vma->vm_start <= addr && vma->vm_end > addr) return vma; /* trawl the tree (there may be multiple mappings in which addr * resides) */ for (n = rb_first(&mm->mm_rb); n; n = rb_next(n)) { vma = rb_entry(n, struct vm_area_struct, vm_rb); if (vma->vm_start > addr) return NULL; if (vma->vm_end > addr) { mm->mmap_cache = vma; return vma; } } return NULL; } EXPORT_SYMBOL(find_vma); /* * find a VMA * - we don't extend stack VMAs under NOMMU conditions */ struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr) { |
7561e8ca0 NOMMU: Revert 'no... |
743 |
return find_vma(mm, addr); |
8feae1311 NOMMU: Make VMAs ... |
744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 |
} /* * expand a stack to a given address * - not supported under NOMMU conditions */ int expand_stack(struct vm_area_struct *vma, unsigned long address) { return -ENOMEM; } /* * look up the first VMA exactly that exactly matches addr * - should be called with mm->mmap_sem at least held readlocked */ static struct vm_area_struct *find_vma_exact(struct mm_struct *mm, unsigned long addr, unsigned long len) { struct vm_area_struct *vma; struct rb_node *n = mm->mm_rb.rb_node; unsigned long end = addr + len; /* check the cache first */ vma = mm->mmap_cache; if (vma && vma->vm_start == addr && vma->vm_end == end) return vma; /* trawl the tree (there may be multiple mappings in which addr * resides) */ for (n = rb_first(&mm->mm_rb); n; n = rb_next(n)) { vma = rb_entry(n, struct vm_area_struct, vm_rb); if (vma->vm_start < addr) continue; if (vma->vm_start > addr) return NULL; if (vma->vm_end == end) { mm->mmap_cache = vma; return vma; } } return NULL; |
1da177e4c Linux-2.6.12-rc2 |
787 788 789 790 791 792 793 794 795 796 797 798 799 800 |
} /* * determine whether a mapping should be permitted and, if so, what sort of * mapping we're capable of supporting */ static int validate_mmap_request(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, unsigned long flags, unsigned long pgoff, unsigned long *_capabilities) { |
8feae1311 NOMMU: Make VMAs ... |
801 |
unsigned long capabilities, rlen; |
1da177e4c Linux-2.6.12-rc2 |
802 803 804 805 |
unsigned long reqprot = prot; int ret; /* do the simple checks first */ |
06aab5a30 NOMMU: Ignore mma... |
806 |
if (flags & MAP_FIXED) { |
1da177e4c Linux-2.6.12-rc2 |
807 808 809 810 811 812 813 814 815 816 |
printk(KERN_DEBUG "%d: Can't do fixed-address/overlay mmap of RAM ", current->pid); return -EINVAL; } if ((flags & MAP_TYPE) != MAP_PRIVATE && (flags & MAP_TYPE) != MAP_SHARED) return -EINVAL; |
f81cff0d4 [PATCH] uclinux: ... |
817 |
if (!len) |
1da177e4c Linux-2.6.12-rc2 |
818 |
return -EINVAL; |
f81cff0d4 [PATCH] uclinux: ... |
819 |
/* Careful about overflows.. */ |
8feae1311 NOMMU: Make VMAs ... |
820 821 |
rlen = PAGE_ALIGN(len); if (!rlen || rlen > TASK_SIZE) |
f81cff0d4 [PATCH] uclinux: ... |
822 |
return -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
823 |
/* offset overflow? */ |
8feae1311 NOMMU: Make VMAs ... |
824 |
if ((pgoff + (rlen >> PAGE_SHIFT)) < pgoff) |
f81cff0d4 [PATCH] uclinux: ... |
825 |
return -EOVERFLOW; |
1da177e4c Linux-2.6.12-rc2 |
826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 |
if (file) { /* validate file mapping requests */ struct address_space *mapping; /* files must support mmap */ if (!file->f_op || !file->f_op->mmap) return -ENODEV; /* work out if what we've got could possibly be shared * - we support chardevs that provide their own "memory" * - we support files/blockdevs that are memory backed */ mapping = file->f_mapping; if (!mapping) |
e9536ae72 [PATCH] struct pa... |
841 |
mapping = file->f_path.dentry->d_inode->i_mapping; |
1da177e4c Linux-2.6.12-rc2 |
842 843 844 845 846 847 848 849 |
capabilities = 0; if (mapping && mapping->backing_dev_info) capabilities = mapping->backing_dev_info->capabilities; if (!capabilities) { /* no explicit capabilities set, so assume some * defaults */ |
e9536ae72 [PATCH] struct pa... |
850 |
switch (file->f_path.dentry->d_inode->i_mode & S_IFMT) { |
1da177e4c Linux-2.6.12-rc2 |
851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 |
case S_IFREG: case S_IFBLK: capabilities = BDI_CAP_MAP_COPY; break; case S_IFCHR: capabilities = BDI_CAP_MAP_DIRECT | BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP; break; default: return -EINVAL; } } /* eliminate any capabilities that we can't support on this * device */ if (!file->f_op->get_unmapped_area) capabilities &= ~BDI_CAP_MAP_DIRECT; if (!file->f_op->read) capabilities &= ~BDI_CAP_MAP_COPY; |
28d7a6ae9 nommu: check fd r... |
874 875 876 |
/* The file shall have been opened with read permission. */ if (!(file->f_mode & FMODE_READ)) return -EACCES; |
1da177e4c Linux-2.6.12-rc2 |
877 878 879 880 881 |
if (flags & MAP_SHARED) { /* do checks for writing, appending and locking */ if ((prot & PROT_WRITE) && !(file->f_mode & FMODE_WRITE)) return -EACCES; |
e9536ae72 [PATCH] struct pa... |
882 |
if (IS_APPEND(file->f_path.dentry->d_inode) && |
1da177e4c Linux-2.6.12-rc2 |
883 884 |
(file->f_mode & FMODE_WRITE)) return -EACCES; |
e9536ae72 [PATCH] struct pa... |
885 |
if (locks_verify_locked(file->f_path.dentry->d_inode)) |
1da177e4c Linux-2.6.12-rc2 |
886 887 888 889 |
return -EAGAIN; if (!(capabilities & BDI_CAP_MAP_DIRECT)) return -ENODEV; |
1da177e4c Linux-2.6.12-rc2 |
890 891 892 893 894 895 896 897 898 899 900 901 902 903 |
/* we mustn't privatise shared mappings */ capabilities &= ~BDI_CAP_MAP_COPY; } else { /* we're going to read the file into private memory we * allocate */ if (!(capabilities & BDI_CAP_MAP_COPY)) return -ENODEV; /* we don't permit a private writable mapping to be * shared with the backing device */ if (prot & PROT_WRITE) capabilities &= ~BDI_CAP_MAP_DIRECT; } |
3c7b20454 nommu: allow priv... |
904 905 906 907 908 909 910 911 912 913 914 915 916 917 |
if (capabilities & BDI_CAP_MAP_DIRECT) { if (((prot & PROT_READ) && !(capabilities & BDI_CAP_READ_MAP)) || ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) || ((prot & PROT_EXEC) && !(capabilities & BDI_CAP_EXEC_MAP)) ) { capabilities &= ~BDI_CAP_MAP_DIRECT; if (flags & MAP_SHARED) { printk(KERN_WARNING "MAP_SHARED not completely supported on !MMU "); return -EINVAL; } } } |
1da177e4c Linux-2.6.12-rc2 |
918 919 |
/* handle executable mappings and implied executable * mappings */ |
e9536ae72 [PATCH] struct pa... |
920 |
if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) { |
1da177e4c Linux-2.6.12-rc2 |
921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 |
if (prot & PROT_EXEC) return -EPERM; } else if ((prot & PROT_READ) && !(prot & PROT_EXEC)) { /* handle implication of PROT_EXEC by PROT_READ */ if (current->personality & READ_IMPLIES_EXEC) { if (capabilities & BDI_CAP_EXEC_MAP) prot |= PROT_EXEC; } } else if ((prot & PROT_READ) && (prot & PROT_EXEC) && !(capabilities & BDI_CAP_EXEC_MAP) ) { /* backing file is not executable, try to copy */ capabilities &= ~BDI_CAP_MAP_DIRECT; } } else { /* anonymous mappings are always memory backed and can be * privately mapped */ capabilities = BDI_CAP_MAP_COPY; /* handle PROT_EXEC implication by PROT_READ */ if ((prot & PROT_READ) && (current->personality & READ_IMPLIES_EXEC)) prot |= PROT_EXEC; } /* allow the security API to have its say */ |
ed0321895 security: Protect... |
952 |
ret = security_file_mmap(file, reqprot, prot, flags, addr, 0); |
1da177e4c Linux-2.6.12-rc2 |
953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 |
if (ret < 0) return ret; /* looks okay */ *_capabilities = capabilities; return 0; } /* * we've determined that we can make the mapping, now translate what we * now know into VMA flags */ static unsigned long determine_vm_flags(struct file *file, unsigned long prot, unsigned long flags, unsigned long capabilities) { unsigned long vm_flags; vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags); |
1da177e4c Linux-2.6.12-rc2 |
973 974 975 976 |
/* vm_flags |= mm->def_flags; */ if (!(capabilities & BDI_CAP_MAP_DIRECT)) { /* attempt to share read-only copies of mapped file chunks */ |
3c7b20454 nommu: allow priv... |
977 |
vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; |
1da177e4c Linux-2.6.12-rc2 |
978 979 |
if (file && !(prot & PROT_WRITE)) vm_flags |= VM_MAYSHARE; |
3c7b20454 nommu: allow priv... |
980 |
} else { |
1da177e4c Linux-2.6.12-rc2 |
981 982 983 |
/* overlay a shareable mapping on the backing device or inode * if possible - used for chardevs, ramfs/tmpfs/shmfs and * romfs/cramfs */ |
3c7b20454 nommu: allow priv... |
984 |
vm_flags |= VM_MAYSHARE | (capabilities & BDI_CAP_VMFLAGS); |
1da177e4c Linux-2.6.12-rc2 |
985 |
if (flags & MAP_SHARED) |
3c7b20454 nommu: allow priv... |
986 |
vm_flags |= VM_SHARED; |
1da177e4c Linux-2.6.12-rc2 |
987 988 989 990 991 992 |
} /* refuse to let anyone share private mappings with this process if * it's being traced - otherwise breakpoints set in it may interfere * with another untraced process */ |
fa8e26ccd tracehook: traceh... |
993 |
if ((flags & MAP_PRIVATE) && tracehook_expect_breakpoints(current)) |
1da177e4c Linux-2.6.12-rc2 |
994 995 996 997 998 999 |
vm_flags &= ~VM_MAYSHARE; return vm_flags; } /* |
8feae1311 NOMMU: Make VMAs ... |
1000 1001 |
* set up a shared mapping on a file (the driver or filesystem provides and * pins the storage) |
1da177e4c Linux-2.6.12-rc2 |
1002 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
1003 |
static int do_mmap_shared_file(struct vm_area_struct *vma) |
1da177e4c Linux-2.6.12-rc2 |
1004 1005 1006 1007 |
{ int ret; ret = vma->vm_file->f_op->mmap(vma->vm_file, vma); |
dd8632a12 NOMMU: Make mmap ... |
1008 1009 |
if (ret == 0) { vma->vm_region->vm_top = vma->vm_region->vm_end; |
645d83c5d NOMMU: Fix MAP_PR... |
1010 |
return 0; |
dd8632a12 NOMMU: Make mmap ... |
1011 |
} |
1da177e4c Linux-2.6.12-rc2 |
1012 1013 |
if (ret != -ENOSYS) return ret; |
3fa30460e nommu: fix an inc... |
1014 1015 1016 |
/* getting -ENOSYS indicates that direct mmap isn't possible (as * opposed to tried but failed) so we can only give a suitable error as * it's not possible to make a private copy if MAP_SHARED was given */ |
1da177e4c Linux-2.6.12-rc2 |
1017 1018 1019 1020 1021 1022 |
return -ENODEV; } /* * set up a private mapping or an anonymous shared mapping */ |
8feae1311 NOMMU: Make VMAs ... |
1023 1024 |
static int do_mmap_private(struct vm_area_struct *vma, struct vm_region *region, |
645d83c5d NOMMU: Fix MAP_PR... |
1025 1026 |
unsigned long len, unsigned long capabilities) |
1da177e4c Linux-2.6.12-rc2 |
1027 |
{ |
8feae1311 NOMMU: Make VMAs ... |
1028 1029 |
struct page *pages; unsigned long total, point, n, rlen; |
1da177e4c Linux-2.6.12-rc2 |
1030 |
void *base; |
8feae1311 NOMMU: Make VMAs ... |
1031 |
int ret, order; |
1da177e4c Linux-2.6.12-rc2 |
1032 1033 1034 1035 1036 |
/* invoke the file's mapping function so that it can keep track of * shared mappings on devices or memory * - VM_MAYSHARE will be set if it may attempt to share */ |
645d83c5d NOMMU: Fix MAP_PR... |
1037 |
if (capabilities & BDI_CAP_MAP_DIRECT) { |
1da177e4c Linux-2.6.12-rc2 |
1038 |
ret = vma->vm_file->f_op->mmap(vma->vm_file, vma); |
dd8632a12 NOMMU: Make mmap ... |
1039 |
if (ret == 0) { |
1da177e4c Linux-2.6.12-rc2 |
1040 |
/* shouldn't return success if we're not sharing */ |
dd8632a12 NOMMU: Make mmap ... |
1041 1042 |
BUG_ON(!(vma->vm_flags & VM_MAYSHARE)); vma->vm_region->vm_top = vma->vm_region->vm_end; |
645d83c5d NOMMU: Fix MAP_PR... |
1043 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1044 |
} |
dd8632a12 NOMMU: Make mmap ... |
1045 1046 |
if (ret != -ENOSYS) return ret; |
1da177e4c Linux-2.6.12-rc2 |
1047 1048 1049 1050 1051 |
/* getting an ENOSYS error indicates that direct mmap isn't * possible (as opposed to tried but failed) so we'll try to * make a private copy of the data and map that instead */ } |
8feae1311 NOMMU: Make VMAs ... |
1052 |
rlen = PAGE_ALIGN(len); |
1da177e4c Linux-2.6.12-rc2 |
1053 1054 1055 1056 |
/* allocate some memory to hold the mapping * - note that this may not return a page-aligned address if the object * we're allocating is smaller than a page */ |
8feae1311 NOMMU: Make VMAs ... |
1057 1058 1059 1060 1061 |
order = get_order(rlen); kdebug("alloc order %d for %lx", order, len); pages = alloc_pages(GFP_KERNEL, order); if (!pages) |
1da177e4c Linux-2.6.12-rc2 |
1062 |
goto enomem; |
8feae1311 NOMMU: Make VMAs ... |
1063 |
total = 1 << order; |
33e5d7697 nommu: fix a numb... |
1064 |
atomic_long_add(total, &mmap_pages_allocated); |
8feae1311 NOMMU: Make VMAs ... |
1065 1066 |
point = rlen >> PAGE_SHIFT; |
dd8632a12 NOMMU: Make mmap ... |
1067 1068 1069 1070 1071 1072 1073 1074 |
/* we allocated a power-of-2 sized page set, so we may want to trim off * the excess */ if (sysctl_nr_trim_pages && total - point >= sysctl_nr_trim_pages) { while (total > point) { order = ilog2(total - point); n = 1 << order; kdebug("shave %lu/%lu @%lu", n, total - point, total); |
33e5d7697 nommu: fix a numb... |
1075 |
atomic_long_sub(n, &mmap_pages_allocated); |
dd8632a12 NOMMU: Make mmap ... |
1076 1077 1078 1079 |
total -= n; set_page_refcounted(pages + total); __free_pages(pages + total, order); } |
8feae1311 NOMMU: Make VMAs ... |
1080 |
} |
8feae1311 NOMMU: Make VMAs ... |
1081 1082 |
for (point = 1; point < total; point++) set_page_refcounted(&pages[point]); |
1da177e4c Linux-2.6.12-rc2 |
1083 |
|
8feae1311 NOMMU: Make VMAs ... |
1084 1085 1086 1087 |
base = page_address(pages); region->vm_flags = vma->vm_flags |= VM_MAPPED_COPY; region->vm_start = (unsigned long) base; region->vm_end = region->vm_start + rlen; |
dd8632a12 NOMMU: Make mmap ... |
1088 |
region->vm_top = region->vm_start + (total << PAGE_SHIFT); |
8feae1311 NOMMU: Make VMAs ... |
1089 1090 1091 |
vma->vm_start = region->vm_start; vma->vm_end = region->vm_start + len; |
1da177e4c Linux-2.6.12-rc2 |
1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 |
if (vma->vm_file) { /* read the contents of a file into the copy */ mm_segment_t old_fs; loff_t fpos; fpos = vma->vm_pgoff; fpos <<= PAGE_SHIFT; old_fs = get_fs(); set_fs(KERNEL_DS); |
8feae1311 NOMMU: Make VMAs ... |
1103 |
ret = vma->vm_file->f_op->read(vma->vm_file, base, rlen, &fpos); |
1da177e4c Linux-2.6.12-rc2 |
1104 1105 1106 1107 1108 1109 |
set_fs(old_fs); if (ret < 0) goto error_free; /* clear the last little bit */ |
8feae1311 NOMMU: Make VMAs ... |
1110 1111 |
if (ret < rlen) memset(base + ret, 0, rlen - ret); |
1da177e4c Linux-2.6.12-rc2 |
1112 |
|
1da177e4c Linux-2.6.12-rc2 |
1113 1114 1115 1116 1117 |
} return 0; error_free: |
8feae1311 NOMMU: Make VMAs ... |
1118 1119 1120 |
free_page_series(region->vm_start, region->vm_end); region->vm_start = vma->vm_start = 0; region->vm_end = vma->vm_end = 0; |
dd8632a12 NOMMU: Make mmap ... |
1121 |
region->vm_top = 0; |
1da177e4c Linux-2.6.12-rc2 |
1122 1123 1124 |
return ret; enomem: |
05ae6fa31 uclinux: add proc... |
1125 1126 1127 |
printk("Allocation of length %lu from process %d (%s) failed ", len, current->pid, current->comm); |
1da177e4c Linux-2.6.12-rc2 |
1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 |
show_free_areas(); return -ENOMEM; } /* * handle mapping creation for uClinux */ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, unsigned long flags, unsigned long pgoff) { |
8feae1311 NOMMU: Make VMAs ... |
1142 1143 |
struct vm_area_struct *vma; struct vm_region *region; |
1da177e4c Linux-2.6.12-rc2 |
1144 |
struct rb_node *rb; |
8feae1311 NOMMU: Make VMAs ... |
1145 |
unsigned long capabilities, vm_flags, result; |
1da177e4c Linux-2.6.12-rc2 |
1146 |
int ret; |
8feae1311 NOMMU: Make VMAs ... |
1147 |
kenter(",%lx,%lx,%lx,%lx,%lx", addr, len, prot, flags, pgoff); |
1da177e4c Linux-2.6.12-rc2 |
1148 1149 1150 1151 |
/* decide whether we should attempt the mapping, and if so what sort of * mapping */ ret = validate_mmap_request(file, addr, len, prot, flags, pgoff, &capabilities); |
8feae1311 NOMMU: Make VMAs ... |
1152 1153 |
if (ret < 0) { kleave(" = %d [val]", ret); |
1da177e4c Linux-2.6.12-rc2 |
1154 |
return ret; |
8feae1311 NOMMU: Make VMAs ... |
1155 |
} |
1da177e4c Linux-2.6.12-rc2 |
1156 |
|
06aab5a30 NOMMU: Ignore mma... |
1157 1158 |
/* we ignore the address hint */ addr = 0; |
1da177e4c Linux-2.6.12-rc2 |
1159 1160 1161 |
/* we've determined that we can make the mapping, now translate what we * now know into VMA flags */ vm_flags = determine_vm_flags(file, prot, flags, capabilities); |
8feae1311 NOMMU: Make VMAs ... |
1162 1163 1164 1165 1166 1167 1168 1169 |
/* we're going to need to record the mapping */ region = kmem_cache_zalloc(vm_region_jar, GFP_KERNEL); if (!region) goto error_getting_region; vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); if (!vma) goto error_getting_vma; |
1da177e4c Linux-2.6.12-rc2 |
1170 |
|
1e2ae599d nommu: struct vm_... |
1171 |
region->vm_usage = 1; |
8feae1311 NOMMU: Make VMAs ... |
1172 1173 |
region->vm_flags = vm_flags; region->vm_pgoff = pgoff; |
5beb49305 mm: change anon_v... |
1174 |
INIT_LIST_HEAD(&vma->anon_vma_chain); |
8feae1311 NOMMU: Make VMAs ... |
1175 1176 |
vma->vm_flags = vm_flags; vma->vm_pgoff = pgoff; |
1da177e4c Linux-2.6.12-rc2 |
1177 |
|
8feae1311 NOMMU: Make VMAs ... |
1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 |
if (file) { region->vm_file = file; get_file(file); vma->vm_file = file; get_file(file); if (vm_flags & VM_EXECUTABLE) { added_exe_file_vma(current->mm); vma->vm_mm = current->mm; } } down_write(&nommu_region_sem); /* if we want to share, we need to check for regions created by other |
1da177e4c Linux-2.6.12-rc2 |
1192 |
* mmap() calls that overlap with our proposed mapping |
8feae1311 NOMMU: Make VMAs ... |
1193 |
* - we can only share with a superset match on most regular files |
1da177e4c Linux-2.6.12-rc2 |
1194 1195 1196 1197 1198 1199 |
* - shared mappings on character devices and memory backed files are * permitted to overlap inexactly as far as we are concerned for in * these cases, sharing is handled in the driver or filesystem rather * than here */ if (vm_flags & VM_MAYSHARE) { |
8feae1311 NOMMU: Make VMAs ... |
1200 1201 |
struct vm_region *pregion; unsigned long pglen, rpglen, pgend, rpgend, start; |
1da177e4c Linux-2.6.12-rc2 |
1202 |
|
8feae1311 NOMMU: Make VMAs ... |
1203 1204 |
pglen = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; pgend = pgoff + pglen; |
165b23927 [PATCH] NOMMU: ma... |
1205 |
|
8feae1311 NOMMU: Make VMAs ... |
1206 1207 |
for (rb = rb_first(&nommu_region_tree); rb; rb = rb_next(rb)) { pregion = rb_entry(rb, struct vm_region, vm_rb); |
1da177e4c Linux-2.6.12-rc2 |
1208 |
|
8feae1311 NOMMU: Make VMAs ... |
1209 |
if (!(pregion->vm_flags & VM_MAYSHARE)) |
1da177e4c Linux-2.6.12-rc2 |
1210 1211 1212 |
continue; /* search for overlapping mappings on the same file */ |
8feae1311 NOMMU: Make VMAs ... |
1213 1214 |
if (pregion->vm_file->f_path.dentry->d_inode != file->f_path.dentry->d_inode) |
1da177e4c Linux-2.6.12-rc2 |
1215 |
continue; |
8feae1311 NOMMU: Make VMAs ... |
1216 |
if (pregion->vm_pgoff >= pgend) |
1da177e4c Linux-2.6.12-rc2 |
1217 |
continue; |
8feae1311 NOMMU: Make VMAs ... |
1218 1219 1220 1221 |
rpglen = pregion->vm_end - pregion->vm_start; rpglen = (rpglen + PAGE_SIZE - 1) >> PAGE_SHIFT; rpgend = pregion->vm_pgoff + rpglen; if (pgoff >= rpgend) |
1da177e4c Linux-2.6.12-rc2 |
1222 |
continue; |
8feae1311 NOMMU: Make VMAs ... |
1223 1224 1225 1226 1227 |
/* handle inexactly overlapping matches between * mappings */ if ((pregion->vm_pgoff != pgoff || rpglen != pglen) && !(pgoff >= pregion->vm_pgoff && pgend <= rpgend)) { /* new mapping is not a subset of the region */ |
1da177e4c Linux-2.6.12-rc2 |
1228 1229 1230 1231 |
if (!(capabilities & BDI_CAP_MAP_DIRECT)) goto sharing_violation; continue; } |
8feae1311 NOMMU: Make VMAs ... |
1232 |
/* we've found a region we can share */ |
1e2ae599d nommu: struct vm_... |
1233 |
pregion->vm_usage++; |
8feae1311 NOMMU: Make VMAs ... |
1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 |
vma->vm_region = pregion; start = pregion->vm_start; start += (pgoff - pregion->vm_pgoff) << PAGE_SHIFT; vma->vm_start = start; vma->vm_end = start + len; if (pregion->vm_flags & VM_MAPPED_COPY) { kdebug("share copy"); vma->vm_flags |= VM_MAPPED_COPY; } else { kdebug("share mmap"); ret = do_mmap_shared_file(vma); if (ret < 0) { vma->vm_region = NULL; vma->vm_start = 0; vma->vm_end = 0; |
1e2ae599d nommu: struct vm_... |
1250 |
pregion->vm_usage--; |
8feae1311 NOMMU: Make VMAs ... |
1251 1252 1253 1254 1255 1256 1257 1258 1259 |
pregion = NULL; goto error_just_free; } } fput(region->vm_file); kmem_cache_free(vm_region_jar, region); region = pregion; result = start; goto share; |
1da177e4c Linux-2.6.12-rc2 |
1260 |
} |
1da177e4c Linux-2.6.12-rc2 |
1261 1262 1263 1264 |
/* obtain the address at which to make a shared mapping * - this is the hook for quasi-memory character devices to * tell us the location of a shared mapping */ |
645d83c5d NOMMU: Fix MAP_PR... |
1265 |
if (capabilities & BDI_CAP_MAP_DIRECT) { |
1da177e4c Linux-2.6.12-rc2 |
1266 1267 1268 1269 1270 |
addr = file->f_op->get_unmapped_area(file, addr, len, pgoff, flags); if (IS_ERR((void *) addr)) { ret = addr; if (ret != (unsigned long) -ENOSYS) |
8feae1311 NOMMU: Make VMAs ... |
1271 |
goto error_just_free; |
1da177e4c Linux-2.6.12-rc2 |
1272 1273 1274 1275 1276 1277 |
/* the driver refused to tell us where to site * the mapping so we'll have to attempt to copy * it */ ret = (unsigned long) -ENODEV; if (!(capabilities & BDI_CAP_MAP_COPY)) |
8feae1311 NOMMU: Make VMAs ... |
1278 |
goto error_just_free; |
1da177e4c Linux-2.6.12-rc2 |
1279 1280 |
capabilities &= ~BDI_CAP_MAP_DIRECT; |
8feae1311 NOMMU: Make VMAs ... |
1281 1282 1283 |
} else { vma->vm_start = region->vm_start = addr; vma->vm_end = region->vm_end = addr + len; |
1da177e4c Linux-2.6.12-rc2 |
1284 1285 1286 |
} } } |
8feae1311 NOMMU: Make VMAs ... |
1287 |
vma->vm_region = region; |
1da177e4c Linux-2.6.12-rc2 |
1288 |
|
645d83c5d NOMMU: Fix MAP_PR... |
1289 1290 1291 |
/* set up the mapping * - the region is filled in if BDI_CAP_MAP_DIRECT is still set */ |
1da177e4c Linux-2.6.12-rc2 |
1292 |
if (file && vma->vm_flags & VM_SHARED) |
8feae1311 NOMMU: Make VMAs ... |
1293 |
ret = do_mmap_shared_file(vma); |
1da177e4c Linux-2.6.12-rc2 |
1294 |
else |
645d83c5d NOMMU: Fix MAP_PR... |
1295 |
ret = do_mmap_private(vma, region, len, capabilities); |
1da177e4c Linux-2.6.12-rc2 |
1296 |
if (ret < 0) |
645d83c5d NOMMU: Fix MAP_PR... |
1297 1298 |
goto error_just_free; add_nommu_region(region); |
8feae1311 NOMMU: Make VMAs ... |
1299 |
|
ea6376395 nommu: fix malloc... |
1300 1301 1302 1303 |
/* clear anonymous mappings that don't ask for uninitialized data */ if (!vma->vm_file && !(flags & MAP_UNINITIALIZED)) memset((void *)region->vm_start, 0, region->vm_end - region->vm_start); |
1da177e4c Linux-2.6.12-rc2 |
1304 |
/* okay... we have a mapping; now we have to register it */ |
8feae1311 NOMMU: Make VMAs ... |
1305 |
result = vma->vm_start; |
1da177e4c Linux-2.6.12-rc2 |
1306 |
|
1da177e4c Linux-2.6.12-rc2 |
1307 |
current->mm->total_vm += len >> PAGE_SHIFT; |
8feae1311 NOMMU: Make VMAs ... |
1308 1309 |
share: add_vma_to_mm(current->mm, vma); |
1da177e4c Linux-2.6.12-rc2 |
1310 |
|
cfe79c00a NOMMU: Avoiding d... |
1311 1312 1313 1314 1315 1316 |
/* we flush the region from the icache only when the first executable * mapping of it is made */ if (vma->vm_flags & VM_EXEC && !region->vm_icache_flushed) { flush_icache_range(region->vm_start, region->vm_end); region->vm_icache_flushed = true; } |
1da177e4c Linux-2.6.12-rc2 |
1317 |
|
cfe79c00a NOMMU: Avoiding d... |
1318 |
up_write(&nommu_region_sem); |
1da177e4c Linux-2.6.12-rc2 |
1319 |
|
8feae1311 NOMMU: Make VMAs ... |
1320 1321 |
kleave(" = %lx", result); return result; |
1da177e4c Linux-2.6.12-rc2 |
1322 |
|
8feae1311 NOMMU: Make VMAs ... |
1323 1324 1325 |
error_just_free: up_write(&nommu_region_sem); error: |
89a864027 NOMMU: Don't pass... |
1326 1327 |
if (region->vm_file) fput(region->vm_file); |
8feae1311 NOMMU: Make VMAs ... |
1328 |
kmem_cache_free(vm_region_jar, region); |
89a864027 NOMMU: Don't pass... |
1329 1330 |
if (vma->vm_file) fput(vma->vm_file); |
8feae1311 NOMMU: Make VMAs ... |
1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 |
if (vma->vm_flags & VM_EXECUTABLE) removed_exe_file_vma(vma->vm_mm); kmem_cache_free(vm_area_cachep, vma); kleave(" = %d", ret); return ret; sharing_violation: up_write(&nommu_region_sem); printk(KERN_WARNING "Attempt to share mismatched mappings "); ret = -EINVAL; goto error; |
1da177e4c Linux-2.6.12-rc2 |
1343 |
|
8feae1311 NOMMU: Make VMAs ... |
1344 1345 1346 1347 1348 |
error_getting_vma: kmem_cache_free(vm_region_jar, region); printk(KERN_WARNING "Allocation of vma for %lu byte allocation" " from process %d failed ", |
1da177e4c Linux-2.6.12-rc2 |
1349 1350 1351 |
len, current->pid); show_free_areas(); return -ENOMEM; |
8feae1311 NOMMU: Make VMAs ... |
1352 1353 1354 1355 |
error_getting_region: printk(KERN_WARNING "Allocation of vm region for %lu byte allocation" " from process %d failed ", |
1da177e4c Linux-2.6.12-rc2 |
1356 1357 1358 1359 |
len, current->pid); show_free_areas(); return -ENOMEM; } |
b50731732 nommu: vmalloc_32... |
1360 |
EXPORT_SYMBOL(do_mmap_pgoff); |
1da177e4c Linux-2.6.12-rc2 |
1361 |
|
66f0dc481 mm: move sys_mmap... |
1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 |
SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, unsigned long, prot, unsigned long, flags, unsigned long, fd, unsigned long, pgoff) { struct file *file = NULL; unsigned long retval = -EBADF; if (!(flags & MAP_ANONYMOUS)) { file = fget(fd); if (!file) goto out; } flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE); down_write(¤t->mm->mmap_sem); retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff); up_write(¤t->mm->mmap_sem); if (file) fput(file); out: return retval; } |
a4679373c Add generic sys_o... |
1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 |
#ifdef __ARCH_WANT_SYS_OLD_MMAP struct mmap_arg_struct { unsigned long addr; unsigned long len; unsigned long prot; unsigned long flags; unsigned long fd; unsigned long offset; }; SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg) { struct mmap_arg_struct a; if (copy_from_user(&a, arg, sizeof(a))) return -EFAULT; if (a.offset & ~PAGE_MASK) return -EINVAL; return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT); } #endif /* __ARCH_WANT_SYS_OLD_MMAP */ |
1da177e4c Linux-2.6.12-rc2 |
1409 |
/* |
8feae1311 NOMMU: Make VMAs ... |
1410 1411 |
* split a vma into two pieces at address 'addr', a new vma is allocated either * for the first part or the tail. |
1da177e4c Linux-2.6.12-rc2 |
1412 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
1413 1414 |
int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, int new_below) |
1da177e4c Linux-2.6.12-rc2 |
1415 |
{ |
8feae1311 NOMMU: Make VMAs ... |
1416 1417 1418 |
struct vm_area_struct *new; struct vm_region *region; unsigned long npages; |
1da177e4c Linux-2.6.12-rc2 |
1419 |
|
8feae1311 NOMMU: Make VMAs ... |
1420 |
kenter(""); |
1da177e4c Linux-2.6.12-rc2 |
1421 |
|
779c10232 nommu: remove a s... |
1422 1423 1424 |
/* we're only permitted to split anonymous regions (these should have * only a single usage on the region) */ if (vma->vm_file) |
8feae1311 NOMMU: Make VMAs ... |
1425 |
return -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
1426 |
|
8feae1311 NOMMU: Make VMAs ... |
1427 1428 |
if (mm->map_count >= sysctl_max_map_count) return -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
1429 |
|
8feae1311 NOMMU: Make VMAs ... |
1430 1431 1432 |
region = kmem_cache_alloc(vm_region_jar, GFP_KERNEL); if (!region) return -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
1433 |
|
8feae1311 NOMMU: Make VMAs ... |
1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 |
new = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); if (!new) { kmem_cache_free(vm_region_jar, region); return -ENOMEM; } /* most fields are the same, copy all, and then fixup */ *new = *vma; *region = *vma->vm_region; new->vm_region = region; npages = (addr - vma->vm_start) >> PAGE_SHIFT; if (new_below) { |
dd8632a12 NOMMU: Make mmap ... |
1448 |
region->vm_top = region->vm_end = new->vm_end = addr; |
8feae1311 NOMMU: Make VMAs ... |
1449 1450 1451 |
} else { region->vm_start = new->vm_start = addr; region->vm_pgoff = new->vm_pgoff += npages; |
1da177e4c Linux-2.6.12-rc2 |
1452 |
} |
8feae1311 NOMMU: Make VMAs ... |
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 |
if (new->vm_ops && new->vm_ops->open) new->vm_ops->open(new); delete_vma_from_mm(vma); down_write(&nommu_region_sem); delete_nommu_region(vma->vm_region); if (new_below) { vma->vm_region->vm_start = vma->vm_start = addr; vma->vm_region->vm_pgoff = vma->vm_pgoff += npages; } else { vma->vm_region->vm_end = vma->vm_end = addr; |
dd8632a12 NOMMU: Make mmap ... |
1465 |
vma->vm_region->vm_top = addr; |
8feae1311 NOMMU: Make VMAs ... |
1466 1467 1468 1469 1470 1471 1472 |
} add_nommu_region(vma->vm_region); add_nommu_region(new->vm_region); up_write(&nommu_region_sem); add_vma_to_mm(mm, vma); add_vma_to_mm(mm, new); return 0; |
1da177e4c Linux-2.6.12-rc2 |
1473 |
} |
3034097a5 [PATCH] NOMMU: Or... |
1474 |
/* |
8feae1311 NOMMU: Make VMAs ... |
1475 1476 |
* shrink a VMA by removing the specified chunk from either the beginning or * the end |
3034097a5 [PATCH] NOMMU: Or... |
1477 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
1478 1479 1480 |
static int shrink_vma(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long from, unsigned long to) |
1da177e4c Linux-2.6.12-rc2 |
1481 |
{ |
8feae1311 NOMMU: Make VMAs ... |
1482 |
struct vm_region *region; |
1da177e4c Linux-2.6.12-rc2 |
1483 |
|
8feae1311 NOMMU: Make VMAs ... |
1484 |
kenter(""); |
1da177e4c Linux-2.6.12-rc2 |
1485 |
|
8feae1311 NOMMU: Make VMAs ... |
1486 1487 1488 1489 1490 1491 1492 1493 |
/* adjust the VMA's pointers, which may reposition it in the MM's tree * and list */ delete_vma_from_mm(vma); if (from > vma->vm_start) vma->vm_end = from; else vma->vm_start = to; add_vma_to_mm(mm, vma); |
1da177e4c Linux-2.6.12-rc2 |
1494 |
|
8feae1311 NOMMU: Make VMAs ... |
1495 1496 |
/* cut the backing region down to size */ region = vma->vm_region; |
1e2ae599d nommu: struct vm_... |
1497 |
BUG_ON(region->vm_usage != 1); |
8feae1311 NOMMU: Make VMAs ... |
1498 1499 1500 |
down_write(&nommu_region_sem); delete_nommu_region(region); |
dd8632a12 NOMMU: Make mmap ... |
1501 1502 1503 1504 |
if (from > region->vm_start) { to = region->vm_top; region->vm_top = region->vm_end = from; } else { |
8feae1311 NOMMU: Make VMAs ... |
1505 |
region->vm_start = to; |
dd8632a12 NOMMU: Make mmap ... |
1506 |
} |
8feae1311 NOMMU: Make VMAs ... |
1507 1508 1509 1510 1511 1512 |
add_nommu_region(region); up_write(&nommu_region_sem); free_page_series(from, to); return 0; } |
1da177e4c Linux-2.6.12-rc2 |
1513 |
|
8feae1311 NOMMU: Make VMAs ... |
1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 |
/* * release a mapping * - under NOMMU conditions the chunk to be unmapped must be backed by a single * VMA, though it need not cover the whole VMA */ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len) { struct vm_area_struct *vma; struct rb_node *rb; unsigned long end = start + len; int ret; |
1da177e4c Linux-2.6.12-rc2 |
1525 |
|
8feae1311 NOMMU: Make VMAs ... |
1526 |
kenter(",%lx,%zx", start, len); |
1da177e4c Linux-2.6.12-rc2 |
1527 |
|
8feae1311 NOMMU: Make VMAs ... |
1528 1529 |
if (len == 0) return -EINVAL; |
365e9c87a [PATCH] mm: updat... |
1530 |
|
8feae1311 NOMMU: Make VMAs ... |
1531 1532 1533 |
/* find the first potentially overlapping VMA */ vma = find_vma(mm, start); if (!vma) { |
33e5d7697 nommu: fix a numb... |
1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 |
static int limit = 0; if (limit < 5) { printk(KERN_WARNING "munmap of memory not mmapped by process %d" " (%s): 0x%lx-0x%lx ", current->pid, current->comm, start, start + len - 1); limit++; } |
8feae1311 NOMMU: Make VMAs ... |
1544 1545 |
return -EINVAL; } |
1da177e4c Linux-2.6.12-rc2 |
1546 |
|
8feae1311 NOMMU: Make VMAs ... |
1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 |
/* we're allowed to split an anonymous VMA but not a file-backed one */ if (vma->vm_file) { do { if (start > vma->vm_start) { kleave(" = -EINVAL [miss]"); return -EINVAL; } if (end == vma->vm_end) goto erase_whole_vma; rb = rb_next(&vma->vm_rb); vma = rb_entry(rb, struct vm_area_struct, vm_rb); } while (rb); kleave(" = -EINVAL [split file]"); return -EINVAL; } else { /* the chunk must be a subset of the VMA found */ if (start == vma->vm_start && end == vma->vm_end) goto erase_whole_vma; if (start < vma->vm_start || end > vma->vm_end) { kleave(" = -EINVAL [superset]"); return -EINVAL; } if (start & ~PAGE_MASK) { kleave(" = -EINVAL [unaligned start]"); return -EINVAL; } if (end != vma->vm_end && end & ~PAGE_MASK) { kleave(" = -EINVAL [unaligned split]"); return -EINVAL; } if (start != vma->vm_start && end != vma->vm_end) { ret = split_vma(mm, vma, start, 1); if (ret < 0) { kleave(" = %d [split]", ret); return ret; } } return shrink_vma(mm, vma, start, end); } |
1da177e4c Linux-2.6.12-rc2 |
1586 |
|
8feae1311 NOMMU: Make VMAs ... |
1587 1588 1589 1590 |
erase_whole_vma: delete_vma_from_mm(vma); delete_vma(mm, vma); kleave(" = 0"); |
1da177e4c Linux-2.6.12-rc2 |
1591 1592 |
return 0; } |
b50731732 nommu: vmalloc_32... |
1593 |
EXPORT_SYMBOL(do_munmap); |
1da177e4c Linux-2.6.12-rc2 |
1594 |
|
6a6160a7b [CVE-2009-0029] S... |
1595 |
SYSCALL_DEFINE2(munmap, unsigned long, addr, size_t, len) |
3034097a5 [PATCH] NOMMU: Or... |
1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 |
{ int ret; struct mm_struct *mm = current->mm; down_write(&mm->mmap_sem); ret = do_munmap(mm, addr, len); up_write(&mm->mmap_sem); return ret; } /* |
8feae1311 NOMMU: Make VMAs ... |
1607 |
* release all the mappings made in a process's VM space |
3034097a5 [PATCH] NOMMU: Or... |
1608 |
*/ |
8feae1311 NOMMU: Make VMAs ... |
1609 |
void exit_mmap(struct mm_struct *mm) |
1da177e4c Linux-2.6.12-rc2 |
1610 |
{ |
8feae1311 NOMMU: Make VMAs ... |
1611 |
struct vm_area_struct *vma; |
1da177e4c Linux-2.6.12-rc2 |
1612 |
|
8feae1311 NOMMU: Make VMAs ... |
1613 1614 |
if (!mm) return; |
1da177e4c Linux-2.6.12-rc2 |
1615 |
|
8feae1311 NOMMU: Make VMAs ... |
1616 |
kenter(""); |
1da177e4c Linux-2.6.12-rc2 |
1617 |
|
8feae1311 NOMMU: Make VMAs ... |
1618 |
mm->total_vm = 0; |
1da177e4c Linux-2.6.12-rc2 |
1619 |
|
8feae1311 NOMMU: Make VMAs ... |
1620 1621 1622 1623 |
while ((vma = mm->mmap)) { mm->mmap = vma->vm_next; delete_vma_from_mm(vma); delete_vma(mm, vma); |
1da177e4c Linux-2.6.12-rc2 |
1624 |
} |
8feae1311 NOMMU: Make VMAs ... |
1625 1626 |
kleave(""); |
1da177e4c Linux-2.6.12-rc2 |
1627 |
} |
1da177e4c Linux-2.6.12-rc2 |
1628 1629 1630 1631 1632 1633 |
unsigned long do_brk(unsigned long addr, unsigned long len) { return -ENOMEM; } /* |
6fa5f80bc [PATCH] NOMMU: Ma... |
1634 1635 |
* expand (or shrink) an existing mapping, potentially moving it at the same * time (controlled by the MREMAP_MAYMOVE flag and available VM space) |
1da177e4c Linux-2.6.12-rc2 |
1636 |
* |
6fa5f80bc [PATCH] NOMMU: Ma... |
1637 |
* under NOMMU conditions, we only permit changing a mapping's size, and only |
8feae1311 NOMMU: Make VMAs ... |
1638 1639 |
* as long as it stays within the region allocated by do_mmap_private() and the * block is not shareable |
1da177e4c Linux-2.6.12-rc2 |
1640 |
* |
6fa5f80bc [PATCH] NOMMU: Ma... |
1641 |
* MREMAP_FIXED is not supported under NOMMU conditions |
1da177e4c Linux-2.6.12-rc2 |
1642 1643 1644 1645 1646 |
*/ unsigned long do_mremap(unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags, unsigned long new_addr) { |
6fa5f80bc [PATCH] NOMMU: Ma... |
1647 |
struct vm_area_struct *vma; |
1da177e4c Linux-2.6.12-rc2 |
1648 1649 |
/* insanity checks first */ |
8feae1311 NOMMU: Make VMAs ... |
1650 |
if (old_len == 0 || new_len == 0) |
1da177e4c Linux-2.6.12-rc2 |
1651 |
return (unsigned long) -EINVAL; |
8feae1311 NOMMU: Make VMAs ... |
1652 1653 |
if (addr & ~PAGE_MASK) return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
1654 1655 |
if (flags & MREMAP_FIXED && new_addr != addr) return (unsigned long) -EINVAL; |
8feae1311 NOMMU: Make VMAs ... |
1656 |
vma = find_vma_exact(current->mm, addr, old_len); |
6fa5f80bc [PATCH] NOMMU: Ma... |
1657 1658 |
if (!vma) return (unsigned long) -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
1659 |
|
6fa5f80bc [PATCH] NOMMU: Ma... |
1660 |
if (vma->vm_end != vma->vm_start + old_len) |
1da177e4c Linux-2.6.12-rc2 |
1661 |
return (unsigned long) -EFAULT; |
6fa5f80bc [PATCH] NOMMU: Ma... |
1662 |
if (vma->vm_flags & VM_MAYSHARE) |
1da177e4c Linux-2.6.12-rc2 |
1663 |
return (unsigned long) -EPERM; |
8feae1311 NOMMU: Make VMAs ... |
1664 |
if (new_len > vma->vm_region->vm_end - vma->vm_region->vm_start) |
1da177e4c Linux-2.6.12-rc2 |
1665 1666 1667 |
return (unsigned long) -ENOMEM; /* all checks complete - do it */ |
6fa5f80bc [PATCH] NOMMU: Ma... |
1668 |
vma->vm_end = vma->vm_start + new_len; |
6fa5f80bc [PATCH] NOMMU: Ma... |
1669 1670 |
return vma->vm_start; } |
b50731732 nommu: vmalloc_32... |
1671 |
EXPORT_SYMBOL(do_mremap); |
6fa5f80bc [PATCH] NOMMU: Ma... |
1672 |
|
6a6160a7b [CVE-2009-0029] S... |
1673 1674 1675 |
SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, unsigned long, new_len, unsigned long, flags, unsigned long, new_addr) |
6fa5f80bc [PATCH] NOMMU: Ma... |
1676 1677 1678 1679 1680 1681 1682 |
{ unsigned long ret; down_write(¤t->mm->mmap_sem); ret = do_mremap(addr, old_len, new_len, flags, new_addr); up_write(¤t->mm->mmap_sem); return ret; |
1da177e4c Linux-2.6.12-rc2 |
1683 |
} |
6aab341e0 mm: re-architect ... |
1684 |
struct page *follow_page(struct vm_area_struct *vma, unsigned long address, |
deceb6cd1 [PATCH] mm: follo... |
1685 |
unsigned int foll_flags) |
1da177e4c Linux-2.6.12-rc2 |
1686 1687 1688 |
{ return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
1689 1690 1691 |
int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long to, unsigned long size, pgprot_t prot) { |
66aa2b4b1 [PATCH] uclinux: ... |
1692 1693 |
vma->vm_start = vma->vm_pgoff << PAGE_SHIFT; return 0; |
1da177e4c Linux-2.6.12-rc2 |
1694 |
} |
22c4af409 [PATCH] nommu: ex... |
1695 |
EXPORT_SYMBOL(remap_pfn_range); |
1da177e4c Linux-2.6.12-rc2 |
1696 |
|
f905bc447 nommu: add new vm... |
1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 |
int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, unsigned long pgoff) { unsigned int size = vma->vm_end - vma->vm_start; if (!(vma->vm_flags & VM_USERMAP)) return -EINVAL; vma->vm_start = (unsigned long)(addr + (pgoff << PAGE_SHIFT)); vma->vm_end = vma->vm_start + size; return 0; } EXPORT_SYMBOL(remap_vmalloc_range); |
1da177e4c Linux-2.6.12-rc2 |
1711 1712 1713 1714 1715 1716 1717 1718 1719 |
void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) { } unsigned long arch_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) { return -ENOMEM; } |
1363c3cd8 [PATCH] Avoiding ... |
1720 |
void arch_unmap_area(struct mm_struct *mm, unsigned long addr) |
1da177e4c Linux-2.6.12-rc2 |
1721 1722 |
{ } |
1da177e4c Linux-2.6.12-rc2 |
1723 1724 1725 1726 1727 |
void unmap_mapping_range(struct address_space *mapping, loff_t const holebegin, loff_t const holelen, int even_cows) { } |
22c4af409 [PATCH] nommu: ex... |
1728 |
EXPORT_SYMBOL(unmap_mapping_range); |
1da177e4c Linux-2.6.12-rc2 |
1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 |
/* * Check that a process has enough memory to allocate a new virtual * mapping. 0 means there is enough memory for the allocation to * succeed and -ENOMEM implies there is not. * * We currently support three overcommit policies, which are set via the * vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting * * Strict overcommit modes added 2002 Feb 26 by Alan Cox. * Additional code 2002 Jul 20 by Robert Love. * * cap_sys_admin is 1 if the process has admin privileges, 0 otherwise. * * Note this is a helper function intended to be used by LSMs which * wish to use this logic. */ |
34b4e4aa3 fix NULL pointer ... |
1746 |
int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) |
1da177e4c Linux-2.6.12-rc2 |
1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 |
{ unsigned long free, allowed; vm_acct_memory(pages); /* * Sometimes we want to use more memory than we have */ if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS) return 0; if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) { unsigned long n; |
347ce434d [PATCH] zoned vm ... |
1760 |
free = global_page_state(NR_FILE_PAGES); |
1da177e4c Linux-2.6.12-rc2 |
1761 1762 1763 1764 1765 1766 1767 1768 |
free += nr_swap_pages; /* * Any slabs which are created with the * SLAB_RECLAIM_ACCOUNT flag claim to have contents * which are reclaimable, under pressure. The dentry * cache and most inode caches should fall into this */ |
972d1a7b1 [PATCH] ZVC: Supp... |
1769 |
free += global_page_state(NR_SLAB_RECLAIMABLE); |
1da177e4c Linux-2.6.12-rc2 |
1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 |
/* * Leave the last 3% for root */ if (!cap_sys_admin) free -= free / 32; if (free > pages) return 0; /* * nr_free_pages() is very expensive on large systems, * only call if we're about to fail. */ n = nr_free_pages(); |
d5ddc79bc [PATCH] overcommi... |
1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 |
/* * Leave reserved pages. The pages are not for anonymous pages. */ if (n <= totalreserve_pages) goto error; else n -= totalreserve_pages; /* * Leave the last 3% for root */ |
1da177e4c Linux-2.6.12-rc2 |
1797 1798 1799 1800 1801 1802 |
if (!cap_sys_admin) n -= n / 32; free += n; if (free > pages) return 0; |
d5ddc79bc [PATCH] overcommi... |
1803 1804 |
goto error; |
1da177e4c Linux-2.6.12-rc2 |
1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 |
} allowed = totalram_pages * sysctl_overcommit_ratio / 100; /* * Leave the last 3% for root */ if (!cap_sys_admin) allowed -= allowed / 32; allowed += total_swap_pages; /* Don't let a single process grow too big: leave 3% of the size of this process for other processes */ |
731572d39 nfsd: fix vm over... |
1817 1818 |
if (mm) allowed -= mm->total_vm / 32; |
1da177e4c Linux-2.6.12-rc2 |
1819 |
|
00a62ce91 mm: fix Committed... |
1820 |
if (percpu_counter_read_positive(&vm_committed_as) < allowed) |
1da177e4c Linux-2.6.12-rc2 |
1821 |
return 0; |
00a62ce91 mm: fix Committed... |
1822 |
|
d5ddc79bc [PATCH] overcommi... |
1823 |
error: |
1da177e4c Linux-2.6.12-rc2 |
1824 1825 1826 1827 1828 1829 1830 1831 1832 |
vm_unacct_memory(pages); return -ENOMEM; } int in_gate_area_no_task(unsigned long addr) { return 0; } |
b0e15190e [PATCH] NOMMU: Ma... |
1833 |
|
d0217ac04 mm: fault feedbac... |
1834 |
int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
b0e15190e [PATCH] NOMMU: Ma... |
1835 1836 |
{ BUG(); |
d0217ac04 mm: fault feedbac... |
1837 |
return 0; |
b0e15190e [PATCH] NOMMU: Ma... |
1838 |
} |
b50731732 nommu: vmalloc_32... |
1839 |
EXPORT_SYMBOL(filemap_fault); |
0ec76a110 [PATCH] NOMMU: Ch... |
1840 1841 1842 1843 1844 1845 1846 |
/* * Access another process' address space. * - source/target buffer must be kernel space */ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) { |
0ec76a110 [PATCH] NOMMU: Ch... |
1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 |
struct vm_area_struct *vma; struct mm_struct *mm; if (addr + len < addr) return 0; mm = get_task_mm(tsk); if (!mm) return 0; down_read(&mm->mmap_sem); /* the access must start within one of the target process's mappings */ |
0159b141d [PATCH] NOMMU: Us... |
1860 1861 |
vma = find_vma(mm, addr); if (vma) { |
0ec76a110 [PATCH] NOMMU: Ch... |
1862 1863 1864 1865 1866 |
/* don't overrun this mapping */ if (addr + len >= vma->vm_end) len = vma->vm_end - addr; /* only read or write mappings where it is permitted */ |
d00c7b993 [PATCH] NOMMU: Pe... |
1867 |
if (write && vma->vm_flags & VM_MAYWRITE) |
7959722b9 NOMMU: Use copy_*... |
1868 1869 |
copy_to_user_page(vma, NULL, addr, (void *) addr, buf, len); |
d00c7b993 [PATCH] NOMMU: Pe... |
1870 |
else if (!write && vma->vm_flags & VM_MAYREAD) |
7959722b9 NOMMU: Use copy_*... |
1871 1872 |
copy_from_user_page(vma, NULL, addr, buf, (void *) addr, len); |
0ec76a110 [PATCH] NOMMU: Ch... |
1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 |
else len = 0; } else { len = 0; } up_read(&mm->mmap_sem); mmput(mm); return len; } |
7e6608724 nommu: fix shared... |
1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 |
/** * nommu_shrink_inode_mappings - Shrink the shared mappings on an inode * @inode: The inode to check * @size: The current filesize of the inode * @newsize: The proposed filesize of the inode * * Check the shared mappings on an inode on behalf of a shrinking truncate to * make sure that that any outstanding VMAs aren't broken and then shrink the * vm_regions that extend that beyond so that do_mmap_pgoff() doesn't * automatically grant mappings that are too large. */ int nommu_shrink_inode_mappings(struct inode *inode, size_t size, size_t newsize) { struct vm_area_struct *vma; struct prio_tree_iter iter; struct vm_region *region; pgoff_t low, high; size_t r_size, r_top; low = newsize >> PAGE_SHIFT; high = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; down_write(&nommu_region_sem); /* search for VMAs that fall within the dead zone */ vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap, low, high) { /* found one - only interested if it's shared out of the page * cache */ if (vma->vm_flags & VM_SHARED) { up_write(&nommu_region_sem); return -ETXTBSY; /* not quite true, but near enough */ } } /* reduce any regions that overlap the dead zone - if in existence, * these will be pointed to by VMAs that don't overlap the dead zone * * we don't check for any regions that start beyond the EOF as there * shouldn't be any */ vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap, 0, ULONG_MAX) { if (!(vma->vm_flags & VM_SHARED)) continue; region = vma->vm_region; r_size = region->vm_top - region->vm_start; r_top = (region->vm_pgoff << PAGE_SHIFT) + r_size; if (r_top > newsize) { region->vm_top -= r_top - newsize; if (region->vm_end > region->vm_top) region->vm_end = region->vm_top; } } up_write(&nommu_region_sem); return 0; } |