Commit ae37461c authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds
Browse files

mm: clean up buffered write code



Rename some variables and fix some types.
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6814d7a9
......@@ -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;
}
}
}
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment