[PATCH] FUSE - readpages operation

This patch adds readpages support to FUSE.

With the help of the readpages() operation multiple reads are bundled
together and sent as a single request to userspace.  This can improve
reading performace.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Miklos Szeredi
2005-09-09 13:10:33 -07:00
committed by Linus Torvalds
parent 06663267b4
commit db50b96c0f
3 changed files with 85 additions and 0 deletions

View File

@@ -227,6 +227,72 @@ static int fuse_readpage(struct file *file, struct page *page)
return err;
}
static int fuse_send_readpages(struct fuse_req *req, struct file *file,
struct inode *inode)
{
loff_t pos = (loff_t) req->pages[0]->index << PAGE_CACHE_SHIFT;
size_t count = req->num_pages << PAGE_CACHE_SHIFT;
unsigned i;
req->out.page_zeroing = 1;
fuse_send_read(req, file, inode, pos, count);
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
if (!req->out.h.error)
SetPageUptodate(page);
unlock_page(page);
}
return req->out.h.error;
}
struct fuse_readpages_data {
struct fuse_req *req;
struct file *file;
struct inode *inode;
};
static int fuse_readpages_fill(void *_data, struct page *page)
{
struct fuse_readpages_data *data = _data;
struct fuse_req *req = data->req;
struct inode *inode = data->inode;
struct fuse_conn *fc = get_fuse_conn(inode);
if (req->num_pages &&
(req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
(req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
req->pages[req->num_pages - 1]->index + 1 != page->index)) {
int err = fuse_send_readpages(req, data->file, inode);
if (err) {
unlock_page(page);
return err;
}
fuse_reset_request(req);
}
req->pages[req->num_pages] = page;
req->num_pages ++;
return 0;
}
static int fuse_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
struct inode *inode = mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_readpages_data data;
int err;
data.file = file;
data.inode = inode;
data.req = fuse_get_request_nonint(fc);
if (!data.req)
return -EINTR;
err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
if (!err && data.req->num_pages)
err = fuse_send_readpages(data.req, file, inode);
fuse_put_request(fc, data.req);
return err;
}
static ssize_t fuse_send_write(struct fuse_req *req, struct file *file,
struct inode *inode, loff_t pos, size_t count)
{
@@ -331,6 +397,7 @@ static struct address_space_operations fuse_file_aops = {
.readpage = fuse_readpage,
.prepare_write = fuse_prepare_write,
.commit_write = fuse_commit_write,
.readpages = fuse_readpages,
.set_page_dirty = fuse_set_page_dirty,
};