From 3a307ffc2730bfa1a4dfa94537be9d412338aad2 Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Tue, 8 May 2007 17:47:32 -0700 Subject: ocfs2: rework ocfs2_buffered_write_cluster() Use some ideas from the new-aops patch series and turn ocfs2_buffered_write_cluster() into a 2 stage operation with the caller copying data in between. The code now understands multiple cluster writes as a result of having to deal with a full page write for greater than 4k pages. This sets us up to easily call into the write path during ->page_mkwrite(). Signed-off-by: Mark Fasheh --- fs/ocfs2/file.c | 121 +++++++++++++++++++++++++++++++------------------------- 1 file changed, 67 insertions(+), 54 deletions(-) (limited to 'fs/ocfs2/file.c') diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 566f9b70ec9..4c850d00c26 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -1335,15 +1335,16 @@ ocfs2_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) *basep = base; } -static struct page * ocfs2_get_write_source(struct ocfs2_buffered_write_priv *bp, +static struct page * ocfs2_get_write_source(char **ret_src_buf, const struct iovec *cur_iov, size_t iov_offset) { int ret; - char *buf; + char *buf = cur_iov->iov_base + iov_offset; struct page *src_page = NULL; + unsigned long off; - buf = cur_iov->iov_base + iov_offset; + off = (unsigned long)(buf) & ~PAGE_CACHE_MASK; if (!segment_eq(get_fs(), KERNEL_DS)) { /* @@ -1355,18 +1356,17 @@ static struct page * ocfs2_get_write_source(struct ocfs2_buffered_write_priv *bp (unsigned long)buf & PAGE_CACHE_MASK, 1, 0, 0, &src_page, NULL); if (ret == 1) - bp->b_src_buf = kmap(src_page); + *ret_src_buf = kmap(src_page) + off; else src_page = ERR_PTR(-EFAULT); } else { - bp->b_src_buf = buf; + *ret_src_buf = buf; } return src_page; } -static void ocfs2_put_write_source(struct ocfs2_buffered_write_priv *bp, - struct page *page) +static void ocfs2_put_write_source(struct page *page) { if (page) { kunmap(page); @@ -1382,10 +1382,12 @@ static ssize_t ocfs2_file_buffered_write(struct file *file, loff_t *ppos, { int ret = 0; ssize_t copied, total = 0; - size_t iov_offset = 0; + size_t iov_offset = 0, bytes; + loff_t pos; const struct iovec *cur_iov = iov; - struct ocfs2_buffered_write_priv bp; - struct page *page; + struct page *user_page, *page; + char *buf, *dst; + void *fsdata; /* * handle partial DIO write. Adjust cur_iov if needed. @@ -1393,21 +1395,38 @@ static ssize_t ocfs2_file_buffered_write(struct file *file, loff_t *ppos, ocfs2_set_next_iovec(&cur_iov, &iov_offset, o_direct_written); do { - bp.b_cur_off = iov_offset; - bp.b_cur_iov = cur_iov; + pos = *ppos; - page = ocfs2_get_write_source(&bp, cur_iov, iov_offset); - if (IS_ERR(page)) { - ret = PTR_ERR(page); + user_page = ocfs2_get_write_source(&buf, cur_iov, iov_offset); + if (IS_ERR(user_page)) { + ret = PTR_ERR(user_page); goto out; } - copied = ocfs2_buffered_write_cluster(file, *ppos, count, - ocfs2_map_and_write_user_data, - &bp); + /* Stay within our page boundaries */ + bytes = min((PAGE_CACHE_SIZE - ((unsigned long)pos & ~PAGE_CACHE_MASK)), + (PAGE_CACHE_SIZE - ((unsigned long)buf & ~PAGE_CACHE_MASK))); + /* Stay within the vector boundary */ + bytes = min_t(size_t, bytes, cur_iov->iov_len - iov_offset); + /* Stay within count */ + bytes = min(bytes, count); + + page = NULL; + ret = ocfs2_write_begin(file, file->f_mapping, pos, bytes, 0, + &page, &fsdata); + if (ret) { + mlog_errno(ret); + goto out; + } - ocfs2_put_write_source(&bp, page); + dst = kmap_atomic(page, KM_USER0); + memcpy(dst + (pos & (PAGE_CACHE_SIZE - 1)), buf, bytes); + kunmap_atomic(dst, KM_USER0); + flush_dcache_page(page); + ocfs2_put_write_source(user_page); + copied = ocfs2_write_end(file, file->f_mapping, pos, bytes, + bytes, page, fsdata); if (copied < 0) { mlog_errno(copied); ret = copied; @@ -1415,7 +1434,7 @@ static ssize_t ocfs2_file_buffered_write(struct file *file, loff_t *ppos, } total += copied; - *ppos = *ppos + copied; + *ppos = pos + copied; count -= copied; ocfs2_set_next_iovec(&cur_iov, &iov_offset, copied); @@ -1585,52 +1604,46 @@ static int ocfs2_splice_write_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf, struct splice_desc *sd) { - int ret, count, total = 0; + int ret, count; ssize_t copied = 0; - struct ocfs2_splice_write_priv sp; + struct file *file = sd->u.file; + unsigned int offset; + struct page *page = NULL; + void *fsdata; + char *src, *dst; ret = buf->ops->confirm(pipe, buf); if (ret) goto out; - sp.s_sd = sd; - sp.s_buf = buf; - sp.s_pipe = pipe; - sp.s_offset = sd->pos & ~PAGE_CACHE_MASK; - sp.s_buf_offset = buf->offset; - + offset = sd->pos & ~PAGE_CACHE_MASK; count = sd->len; - if (count + sp.s_offset > PAGE_CACHE_SIZE) - count = PAGE_CACHE_SIZE - sp.s_offset; + if (count + offset > PAGE_CACHE_SIZE) + count = PAGE_CACHE_SIZE - offset; - do { - /* - * splice wants us to copy up to one page at a - * time. For pagesize > cluster size, this means we - * might enter ocfs2_buffered_write_cluster() more - * than once, so keep track of our progress here. - */ - copied = ocfs2_buffered_write_cluster(sd->u.file, - (loff_t)sd->pos + total, - count, - ocfs2_map_and_write_splice_data, - &sp); - if (copied < 0) { - mlog_errno(copied); - ret = copied; - goto out; - } + ret = ocfs2_write_begin(file, file->f_mapping, sd->pos, count, 0, + &page, &fsdata); + if (ret) { + mlog_errno(ret); + goto out; + } - count -= copied; - sp.s_offset += copied; - sp.s_buf_offset += copied; - total += copied; - } while (count); + src = buf->ops->map(pipe, buf, 1); + dst = kmap_atomic(page, KM_USER1); + memcpy(dst + offset, src + buf->offset, count); + kunmap_atomic(page, KM_USER1); + buf->ops->unmap(pipe, buf, src); - ret = 0; + copied = ocfs2_write_end(file, file->f_mapping, sd->pos, count, count, + page, fsdata); + if (copied < 0) { + mlog_errno(copied); + ret = copied; + goto out; + } out: - return total ? total : ret; + return copied ? copied : ret; } static ssize_t __ocfs2_file_splice_write(struct pipe_inode_info *pipe, -- cgit v1.2.3