diff options
Diffstat (limited to 'mm/filemap.c')
| -rw-r--r-- | mm/filemap.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 4bf7d1ab6c2..f74d0520186 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1838,16 +1838,15 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, size_t count, ssize_t written) { struct file *file = iocb->ki_filp; - struct address_space * mapping = file->f_mapping; + struct address_space *mapping = file->f_mapping; const struct address_space_operations *a_ops = mapping->a_ops; struct inode *inode = mapping->host; long status = 0; struct page *page; struct page *cached_page = NULL; - size_t bytes; struct pagevec lru_pvec; const struct iovec *cur_iov = iov; /* current iovec */ - size_t iov_base = 0; /* offset in the current iovec */ + size_t iov_offset = 0; /* offset in the current iovec */ char __user *buf; pagevec_init(&lru_pvec, 0); @@ -1858,31 +1857,33 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, if (likely(nr_segs == 1)) buf = iov->iov_base + written; else { - filemap_set_next_iovec(&cur_iov, &iov_base, written); - buf = cur_iov->iov_base + iov_base; + filemap_set_next_iovec(&cur_iov, &iov_offset, written); + buf = cur_iov->iov_base + iov_offset; } do { - unsigned long index; - unsigned long offset; - unsigned long maxlen; - size_t copied; + pgoff_t index; /* Pagecache index for current page */ + unsigned long offset; /* Offset into pagecache page */ + unsigned long maxlen; /* Bytes remaining in current iovec */ + size_t bytes; /* Bytes to write to page */ + size_t copied; /* Bytes copied from user */ - offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */ + offset = (pos & (PAGE_CACHE_SIZE - 1)); index = pos >> PAGE_CACHE_SHIFT; bytes = PAGE_CACHE_SIZE - offset; if (bytes > count) bytes = count; + maxlen = cur_iov->iov_len - iov_offset; + if (maxlen > bytes) + maxlen = bytes; + /* * Bring in the user page that we will copy from _first_. * Otherwise there's a nasty deadlock on copying from the * same page as we're writing to, without it being marked * up-to-date. */ - maxlen = cur_iov->iov_len - iov_base; - if (maxlen > bytes) - maxlen = bytes; fault_in_pages_readable(buf, maxlen); page = __grab_cache_page(mapping,index,&cached_page,&lru_pvec); @@ -1913,7 +1914,7 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, buf, bytes); else copied = filemap_copy_from_user_iovec(page, offset, - cur_iov, iov_base, bytes); + cur_iov, iov_offset, bytes); flush_dcache_page(page); status = a_ops->commit_write(file, page, offset, offset+bytes); if (status == AOP_TRUNCATED_PAGE) { @@ -1931,12 +1932,12 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, buf += status; if (unlikely(nr_segs > 1)) { filemap_set_next_iovec(&cur_iov, - &iov_base, status); + &iov_offset, status); if (count) buf = cur_iov->iov_base + - iov_base; + iov_offset; } else { - iov_base += status; + iov_offset += status; } } } |