X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=mm%2Fvmalloc.c;h=86897ee792d6b4a2f8e00a94cf4b12e2c1d6f075;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=c0504f1e34ebdbd2003ba8aaa63287f366b100cb;hpb=43bc926fffd92024b46cafaf7350d669ba9ca884;p=linux-2.6.git diff --git a/mm/vmalloc.c b/mm/vmalloc.c index c0504f1e3..86897ee79 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -24,6 +24,9 @@ DEFINE_RWLOCK(vmlist_lock); struct vm_struct *vmlist; +static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, + int node); + static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) { pte_t *pte; @@ -157,13 +160,15 @@ int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages) return err; } -struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, - unsigned long start, unsigned long end, int node) +static struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, + unsigned long start, unsigned long end, + int node, gfp_t gfp_mask) { struct vm_struct **p, *tmp, *area; unsigned long align = 1; unsigned long addr; + BUG_ON(in_interrupt()); if (flags & VM_IOREMAP) { int bit = fls(size); @@ -176,16 +181,13 @@ struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, } addr = ALIGN(start, align); size = PAGE_ALIGN(size); + if (unlikely(!size)) + return NULL; - area = kmalloc_node(sizeof(*area), GFP_KERNEL, node); + area = kmalloc_node(sizeof(*area), gfp_mask & GFP_LEVEL_MASK, node); if (unlikely(!area)) return NULL; - if (unlikely(!size)) { - kfree (area); - return NULL; - } - /* * We always allocate a guard page. */ @@ -233,12 +235,11 @@ out: struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, unsigned long start, unsigned long end) { - return __get_vm_area_node(size, flags, start, end, -1); + return __get_vm_area_node(size, flags, start, end, -1, GFP_KERNEL); } /** * get_vm_area - reserve a contingous kernel virtual area - * * @size: size of the area * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC * @@ -251,13 +252,28 @@ struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) return __get_vm_area(size, flags, VMALLOC_START, VMALLOC_END); } -struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, int node) +struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, + int node, gfp_t gfp_mask) +{ + return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node, + gfp_mask); +} + +/* Caller must hold vmlist_lock */ +static struct vm_struct *__find_vm_area(void *addr) { - return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node); + struct vm_struct *tmp; + + for (tmp = vmlist; tmp != NULL; tmp = tmp->next) { + if (tmp->addr == addr) + break; + } + + return tmp; } /* Caller must hold vmlist_lock */ -struct vm_struct *__remove_vm_area(void *addr) +static struct vm_struct *__remove_vm_area(void *addr) { struct vm_struct **p, *tmp; @@ -280,7 +296,6 @@ found: /** * remove_vm_area - find and remove a contingous kernel virtual area - * * @addr: base address * * Search for the kernel VM area starting at @addr, and remove it. @@ -317,6 +332,8 @@ void __vunmap(void *addr, int deallocate_pages) return; } + debug_check_no_locks_freed(addr, area->size); + if (deallocate_pages) { int i; @@ -325,7 +342,7 @@ void __vunmap(void *addr, int deallocate_pages) __free_page(area->pages[i]); } - if (area->nr_pages > PAGE_SIZE/sizeof(struct page *)) + if (area->flags & VM_VPAGES) vfree(area->pages); else kfree(area->pages); @@ -337,7 +354,6 @@ void __vunmap(void *addr, int deallocate_pages) /** * vfree - release memory allocated by vmalloc() - * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, as @@ -355,7 +371,6 @@ EXPORT_SYMBOL(vfree); /** * vunmap - release virtual mapping obtained by vmap() - * * @addr: memory base address * * Free the virtually contiguous memory area starting at @addr, @@ -372,7 +387,6 @@ EXPORT_SYMBOL(vunmap); /** * vmap - map an array of pages into virtually contiguous space - * * @pages: array of page pointers * @count: number of pages to map * @flags: vm_area->flags @@ -412,10 +426,14 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, area->nr_pages = nr_pages; /* Please note that the recursion is strictly bounded. */ - if (array_size > PAGE_SIZE) + if (array_size > PAGE_SIZE) { pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node); - else - pages = kmalloc_node(array_size, (gfp_mask & ~__GFP_HIGHMEM), node); + area->flags |= VM_VPAGES; + } else { + pages = kmalloc_node(array_size, + (gfp_mask & ~(__GFP_HIGHMEM | __GFP_ZERO)), + node); + } area->pages = pages; if (!area->pages) { remove_vm_area(area->addr); @@ -452,7 +470,6 @@ void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot) /** * __vmalloc_node - allocate virtually contiguous memory - * * @size: allocation size * @gfp_mask: flags for the page level allocator * @prot: protection mask for the allocated pages @@ -462,8 +479,8 @@ void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot) * allocator with @gfp_mask flags. Map them into contiguous * kernel virtual space, using a pagetable protection of @prot. */ -void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, - int node) +static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, + int node) { struct vm_struct *area; @@ -471,13 +488,12 @@ void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, if (!size || (size >> PAGE_SHIFT) > num_physpages) return NULL; - area = get_vm_area_node(size, VM_ALLOC, node); + area = get_vm_area_node(size, VM_ALLOC, node, gfp_mask); if (!area) return NULL; return __vmalloc_area_node(area, gfp_mask, prot, node); } -EXPORT_SYMBOL(__vmalloc_node); void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) { @@ -487,36 +503,56 @@ EXPORT_SYMBOL(__vmalloc); /** * vmalloc - allocate virtually contiguous memory - * * @size: allocation size - * * Allocate enough pages to cover @size from the page level * allocator and map them into contiguous kernel virtual space. * - * For tight cotrol over page level allocator and protection flags + * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ void *vmalloc(unsigned long size) { - return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL); + return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL); } EXPORT_SYMBOL(vmalloc); /** - * vmalloc_node - allocate memory on a specific node + * vmalloc_user - allocate zeroed virtually contiguous memory for userspace + * @size: allocation size * + * The resulting memory area is zeroed so it can be mapped to userspace + * without leaking data. + */ +void *vmalloc_user(unsigned long size) +{ + struct vm_struct *area; + void *ret; + + ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); + if (ret) { + write_lock(&vmlist_lock); + area = __find_vm_area(ret); + area->flags |= VM_USERMAP; + write_unlock(&vmlist_lock); + } + return ret; +} +EXPORT_SYMBOL(vmalloc_user); + +/** + * vmalloc_node - allocate memory on a specific node * @size: allocation size * @node: numa node * * Allocate enough pages to cover @size from the page level * allocator and map them into contiguous kernel virtual space. * - * For tight cotrol over page level allocator and protection flags + * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ void *vmalloc_node(unsigned long size, int node) { - return __vmalloc_node(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, node); + return __vmalloc_node(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, node); } EXPORT_SYMBOL(vmalloc_node); @@ -526,14 +562,13 @@ EXPORT_SYMBOL(vmalloc_node); /** * 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 cotrol over page level allocator and protection flags + * For tight control over page level allocator and protection flags * use __vmalloc() instead. */ @@ -544,7 +579,6 @@ void *vmalloc_exec(unsigned long size) /** * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) - * * @size: allocation size * * Allocate enough 32bit PA addressable pages to cover @size from the @@ -556,6 +590,29 @@ void *vmalloc_32(unsigned long size) } 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. + */ +void *vmalloc_32_user(unsigned long size) +{ + struct vm_struct *area; + void *ret; + + ret = __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL); + if (ret) { + write_lock(&vmlist_lock); + area = __find_vm_area(ret); + area->flags |= VM_USERMAP; + write_unlock(&vmlist_lock); + } + return ret; +} +EXPORT_SYMBOL(vmalloc_32_user); + long vread(char *buf, char *addr, unsigned long count) { struct vm_struct *tmp; @@ -630,3 +687,63 @@ finished: read_unlock(&vmlist_lock); return buf - buf_start; } + +/** + * remap_vmalloc_range - map vmalloc pages to userspace + * @vma: vma to cover (map full range of vma) + * @addr: vmalloc memory + * @pgoff: number of pages into addr before first page to map + * @returns: 0 for success, -Exxx on failure + * + * This function checks that addr is a valid vmalloc'ed area, and + * that it is big enough to cover the vma. Will return failure if + * that criteria isn't met. + * + * Similar to remap_pfn_range (see mm/memory.c) + */ +int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, + unsigned long pgoff) +{ + struct vm_struct *area; + unsigned long uaddr = vma->vm_start; + unsigned long usize = vma->vm_end - vma->vm_start; + int ret; + + if ((PAGE_SIZE-1) & (unsigned long)addr) + return -EINVAL; + + read_lock(&vmlist_lock); + area = __find_vm_area(addr); + if (!area) + goto out_einval_locked; + + if (!(area->flags & VM_USERMAP)) + goto out_einval_locked; + + if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE) + goto out_einval_locked; + read_unlock(&vmlist_lock); + + addr += pgoff << PAGE_SHIFT; + do { + struct page *page = vmalloc_to_page(addr); + ret = vm_insert_page(vma, uaddr, page); + if (ret) + return ret; + + uaddr += PAGE_SIZE; + addr += PAGE_SIZE; + usize -= PAGE_SIZE; + } while (usize > 0); + + /* Prevent "things" like memory migration? VM_flags need a cleanup... */ + vma->vm_flags |= VM_RESERVED; + + return ret; + +out_einval_locked: + read_unlock(&vmlist_lock); + return -EINVAL; +} +EXPORT_SYMBOL(remap_vmalloc_range); +