From a92adc824ed5feaa2d4f7029f21170f574987aee Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Thu, 10 Oct 2013 17:10:16 +0400 Subject: [PATCH] fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov Signed-off-by: Pavel Emelyanov Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 2489aca..592d7b48 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -671,6 +671,15 @@ static void fuse_read_update_size(struct inode *inode, loff_t size, spin_unlock(&fc->lock); } +static void fuse_short_read(struct fuse_req *req, struct inode *inode, + u64 attr_ver) +{ + size_t num_read = req->out.args[0].size; + + loff_t pos = page_offset(req->pages[0]) + num_read; + fuse_read_update_size(inode, pos, attr_ver); +} + static int fuse_readpage(struct file *file, struct page *page) { struct fuse_io_priv io = { .async = 0, .file = file }; @@ -708,18 +717,18 @@ static int fuse_readpage(struct file *file, struct page *page) req->page_descs[0].length = count; num_read = fuse_send_read(req, &io, pos, count, NULL); err = req->out.h.error; - fuse_put_request(fc, req); if (!err) { /* * Short read means EOF. If file size is larger, truncate it */ if (num_read < count) - fuse_read_update_size(inode, pos + num_read, attr_ver); + fuse_short_read(req, inode, attr_ver); SetPageUptodate(page); } + fuse_put_request(fc, req); fuse_invalidate_atime(inode); out: unlock_page(page); @@ -742,13 +751,9 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) /* * Short read means EOF. If file size is larger, truncate it */ - if (!req->out.h.error && num_read < count) { - loff_t pos; + if (!req->out.h.error && num_read < count) + fuse_short_read(req, inode, req->misc.read.attr_ver); - pos = page_offset(req->pages[0]) + num_read; - fuse_read_update_size(inode, pos, - req->misc.read.attr_ver); - } fuse_invalidate_atime(inode); } -- 2.7.4