diff options
Diffstat (limited to 'mm/filemap.h')
-rw-r--r-- | mm/filemap.h | 103 |
1 files changed, 0 insertions, 103 deletions
diff --git a/mm/filemap.h b/mm/filemap.h deleted file mode 100644 index c2bff04..0000000 --- a/mm/filemap.h +++ /dev/null @@ -1,103 +0,0 @@ -/* - * linux/mm/filemap.h - * - * Copyright (C) 1994-1999 Linus Torvalds - */ - -#ifndef __FILEMAP_H -#define __FILEMAP_H - -#include <linux/types.h> -#include <linux/fs.h> -#include <linux/mm.h> -#include <linux/highmem.h> -#include <linux/uio.h> -#include <linux/uaccess.h> - -size_t -__filemap_copy_from_user_iovec_inatomic(char *vaddr, - const struct iovec *iov, - size_t base, - size_t bytes); - -/* - * Copy as much as we can into the page and return the number of bytes which - * were sucessfully copied. If a fault is encountered then clear the page - * out to (offset+bytes) and return the number of bytes which were copied. - * - * NOTE: For this to work reliably we really want copy_from_user_inatomic_nocache - * to *NOT* zero any tail of the buffer that it failed to copy. If it does, - * and if the following non-atomic copy succeeds, then there is a small window - * where the target page contains neither the data before the write, nor the - * data after the write (it contains zero). A read at this time will see - * data that is inconsistent with any ordering of the read and the write. - * (This has been detected in practice). - */ -static inline size_t -filemap_copy_from_user(struct page *page, unsigned long offset, - const char __user *buf, unsigned bytes) -{ - char *kaddr; - int left; - - kaddr = kmap_atomic(page, KM_USER0); - left = __copy_from_user_inatomic_nocache(kaddr + offset, buf, bytes); - kunmap_atomic(kaddr, KM_USER0); - - if (left != 0) { - /* Do it the slow way */ - kaddr = kmap(page); - left = __copy_from_user_nocache(kaddr + offset, buf, bytes); - kunmap(page); - } - return bytes - left; -} - -/* - * This has the same sideeffects and return value as filemap_copy_from_user(). - * The difference is that on a fault we need to memset the remainder of the - * page (out to offset+bytes), to emulate filemap_copy_from_user()'s - * single-segment behaviour. - */ -static inline size_t -filemap_copy_from_user_iovec(struct page *page, unsigned long offset, - const struct iovec *iov, size_t base, size_t bytes) -{ - char *kaddr; - size_t copied; - - kaddr = kmap_atomic(page, KM_USER0); - copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset, iov, - base, bytes); - kunmap_atomic(kaddr, KM_USER0); - if (copied != bytes) { - kaddr = kmap(page); - copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset, iov, - base, bytes); - if (bytes - copied) - memset(kaddr + offset + copied, 0, bytes - copied); - kunmap(page); - } - return copied; -} - -static inline void -filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) -{ - const struct iovec *iov = *iovp; - size_t base = *basep; - - do { - int copy = min(bytes, iov->iov_len - base); - - bytes -= copy; - base += copy; - if (iov->iov_len == base) { - iov++; - base = 0; - } - } while (bytes); - *iovp = iov; - *basep = base; -} -#endif |