X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Futil.c;h=7c122e49f769ccea98ae105746e0238acc1652ce;hb=f4112de6b679d84bd9b9681c7504be7bdfb7c7d5;hp=7368479220b3b4c3d8c12a9306bb18221d9a99b9;hpb=40c07ae8daa659b8feb149c84731629386873c16;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/util.c b/mm/util.c index 7368479..7c122e4 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1,26 +1,13 @@ +#include #include #include #include #include +#include #include /** - * __kzalloc - allocate memory. The memory is set to zero. - * @size: how many bytes of memory are required. - * @flags: the type of memory to allocate. - */ -void *__kzalloc(size_t size, gfp_t flags) -{ - void *ret = ____kmalloc(size, flags); - if (ret) - memset(ret, 0, size); - return ret; -} -EXPORT_SYMBOL(__kzalloc); - -/* * kstrdup - allocate space for and copy an existing string - * * @s: the string to duplicate * @gfp: the GFP mask used in the kmalloc() call when allocating memory */ @@ -33,16 +20,167 @@ char *kstrdup(const char *s, gfp_t gfp) return NULL; len = strlen(s) + 1; - buf = ____kmalloc(len, gfp); + buf = kmalloc_track_caller(len, gfp); if (buf) memcpy(buf, s, len); return buf; } EXPORT_SYMBOL(kstrdup); +/** + * kstrndup - allocate space for and copy an existing string + * @s: the string to duplicate + * @max: read at most @max chars from @s + * @gfp: the GFP mask used in the kmalloc() call when allocating memory + */ +char *kstrndup(const char *s, size_t max, gfp_t gfp) +{ + size_t len; + char *buf; + + if (!s) + return NULL; + + len = strnlen(s, max); + buf = kmalloc_track_caller(len+1, gfp); + if (buf) { + memcpy(buf, s, len); + buf[len] = '\0'; + } + return buf; +} +EXPORT_SYMBOL(kstrndup); + +/** + * kmemdup - duplicate region of memory + * + * @src: memory region to duplicate + * @len: memory region length + * @gfp: GFP mask to use + */ +void *kmemdup(const void *src, size_t len, gfp_t gfp) +{ + void *p; + + p = kmalloc_track_caller(len, gfp); + if (p) + memcpy(p, src, len); + return p; +} +EXPORT_SYMBOL(kmemdup); + +/** + * memdup_user - duplicate memory region from user space + * + * @src: source address in user space + * @len: number of bytes to copy + * + * Returns an ERR_PTR() on failure. + */ +void *memdup_user(const void __user *src, size_t len) +{ + void *p; + + /* + * Always use GFP_KERNEL, since copy_from_user() can sleep and + * cause pagefault, which makes it pointless to use GFP_NOFS + * or GFP_ATOMIC. + */ + p = kmalloc_track_caller(len, GFP_KERNEL); + if (!p) + return ERR_PTR(-ENOMEM); + + if (copy_from_user(p, src, len)) { + kfree(p); + return ERR_PTR(-EFAULT); + } + + return p; +} +EXPORT_SYMBOL(memdup_user); + +/** + * __krealloc - like krealloc() but don't free @p. + * @p: object to reallocate memory for. + * @new_size: how many bytes of memory are required. + * @flags: the type of memory to allocate. + * + * This function is like krealloc() except it never frees the originally + * allocated buffer. Use this if you don't want to free the buffer immediately + * like, for example, with RCU. + */ +void *__krealloc(const void *p, size_t new_size, gfp_t flags) +{ + void *ret; + size_t ks = 0; + + if (unlikely(!new_size)) + return ZERO_SIZE_PTR; + + if (p) + ks = ksize(p); + + if (ks >= new_size) + return (void *)p; + + ret = kmalloc_track_caller(new_size, flags); + if (ret && p) + memcpy(ret, p, ks); + + return ret; +} +EXPORT_SYMBOL(__krealloc); + +/** + * krealloc - reallocate memory. The contents will remain unchanged. + * @p: object to reallocate memory for. + * @new_size: how many bytes of memory are required. + * @flags: the type of memory to allocate. + * + * The contents of the object pointed to are preserved up to the + * lesser of the new and old sizes. If @p is %NULL, krealloc() + * behaves exactly like kmalloc(). If @size is 0 and @p is not a + * %NULL pointer, the object pointed to is freed. + */ +void *krealloc(const void *p, size_t new_size, gfp_t flags) +{ + void *ret; + + if (unlikely(!new_size)) { + kfree(p); + return ZERO_SIZE_PTR; + } + + ret = __krealloc(p, new_size, flags); + if (ret && p != ret) + kfree(p); + + return ret; +} +EXPORT_SYMBOL(krealloc); + +/** + * kzfree - like kfree but zero memory + * @p: object to free memory of + * + * The memory of the object @p points to is zeroed before freed. + * If @p is %NULL, kzfree() does nothing. + */ +void kzfree(const void *p) +{ + size_t ks; + void *mem = (void *)p; + + if (unlikely(ZERO_OR_NULL_PTR(mem))) + return; + ks = ksize(mem); + memset(mem, 0, ks); + kfree(mem); +} +EXPORT_SYMBOL(kzfree); + /* * strndup_user - duplicate an existing string from user space - * * @s: The string to duplicate * @n: Maximum number of bytes to copy, including the trailing NUL. */ @@ -74,3 +212,27 @@ char *strndup_user(const char __user *s, long n) return p; } EXPORT_SYMBOL(strndup_user); + +#ifndef HAVE_ARCH_PICK_MMAP_LAYOUT +void arch_pick_mmap_layout(struct mm_struct *mm) +{ + mm->mmap_base = TASK_UNMAPPED_BASE; + mm->get_unmapped_area = arch_get_unmapped_area; + mm->unmap_area = arch_unmap_area; +} +#endif + +int __attribute__((weak)) get_user_pages_fast(unsigned long start, + int nr_pages, int write, struct page **pages) +{ + struct mm_struct *mm = current->mm; + int ret; + + down_read(&mm->mmap_sem); + ret = get_user_pages(current, mm, start, nr_pages, + write, 0, pages, NULL); + up_read(&mm->mmap_sem); + + return ret; +} +EXPORT_SYMBOL_GPL(get_user_pages_fast);