Re: [PATCH 04/14] fuse: Prepare to handle multiple pages in writeback

From: Miklos Szeredi
Date: Thu Apr 25 2013 - 06:22:16 EST


On Mon, Apr 1, 2013 at 12:41 PM, Maxim V. Patlasov
<MPatlasov@xxxxxxxxxxxxx> wrote:
>
> The .writepages callback will issue writeback requests with more than one
> page aboard. Make existing end/check code be aware of this.
>
> Original patch by: Pavel Emelyanov <xemul@xxxxxxxxxx>

If this patch was written by Pavel and then modified by you then
please add a "From:" header at the top of the patch instead. See
Documentation/SubmittingPatches.

> Signed-off-by: Maxim Patlasov <MPatlasov@xxxxxxxxxxxxx>
> ---
> fs/fuse/file.c | 22 +++++++++++++++-------
> 1 files changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/fs/fuse/file.c b/fs/fuse/file.c
> index 648de34..ee44b24 100644
> --- a/fs/fuse/file.c
> +++ b/fs/fuse/file.c
> @@ -345,7 +345,8 @@ static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
>
> BUG_ON(req->inode != inode);
> curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
> - if (curr_index == index) {
> + if (curr_index <= index &&
> + index < curr_index + req->num_pages) {
> found = true;
> break;
> }
> @@ -1295,7 +1296,10 @@ static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
>
> static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
> {
> - __free_page(req->pages[0]);
> + int i;
> +
> + for (i = 0; i < req->num_pages; i++)
> + __free_page(req->pages[i]);
> fuse_file_put(req->ff, false);
> }
>
> @@ -1304,10 +1308,13 @@ static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
> struct inode *inode = req->inode;
> struct fuse_inode *fi = get_fuse_inode(inode);
> struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
> + int i;
>
> list_del(&req->writepages_entry);
> - dec_bdi_stat(bdi, BDI_WRITEBACK);
> - dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP);
> + for (i = 0; i < req->num_pages; i++) {
> + dec_bdi_stat(bdi, BDI_WRITEBACK);
> + dec_zone_page_state(req->pages[i], NR_WRITEBACK_TEMP);
> + }
> bdi_writeout_inc(bdi);
> wake_up(&fi->page_waitq);
> }
> @@ -1320,14 +1327,15 @@ __acquires(fc->lock)
> struct fuse_inode *fi = get_fuse_inode(req->inode);
> loff_t size = i_size_read(req->inode);
> struct fuse_write_in *inarg = &req->misc.write.in;
> + __u64 data_size = req->num_pages * PAGE_CACHE_SIZE;
>
> if (!fc->connected)
> goto out_free;
>
> - if (inarg->offset + PAGE_CACHE_SIZE <= size) {
> - inarg->size = PAGE_CACHE_SIZE;
> + if (inarg->offset + data_size <= size) {
> + inarg->size = data_size;
> } else if (inarg->offset < size) {
> - inarg->size = size & (PAGE_CACHE_SIZE - 1);
> + inarg->size = size - inarg->offset;
> } else {
> /* Got truncated off completely */
> goto out_free;
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/