From: Miklos Szeredi If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume, that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 42 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 38 insertions(+), 4 deletions(-) Index: linux/fs/fuse/file.c =================================================================== --- linux.orig/fs/fuse/file.c 2008-03-17 18:26:43.000000000 +0100 +++ linux/fs/fuse/file.c 2008-03-17 18:27:11.000000000 +0100 @@ -398,11 +398,26 @@ static size_t fuse_send_read(struct fuse return req->out.args[0].size; } +static void fuse_read_update_size(struct inode *inode, loff_t size) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_inode *fi = get_fuse_inode(inode); + + spin_lock(&fc->lock); + fi->attr_version = ++fc->attr_version; + if (size < inode->i_size) + i_size_write(inode, size); + spin_unlock(&fc->lock); +} + static int fuse_readpage(struct file *file, struct page *page) { struct inode *inode = page->mapping->host; struct fuse_conn *fc = get_fuse_conn(inode); struct fuse_req *req; + size_t num_read; + loff_t pos = page_offset(page); + size_t count = PAGE_CACHE_SIZE; int err; err = -EIO; @@ -424,12 +439,20 @@ static int fuse_readpage(struct file *fi req->out.page_zeroing = 1; req->num_pages = 1; req->pages[0] = page; - fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE, - NULL); + num_read = fuse_send_read(req, file, inode, pos, count, NULL); err = req->out.h.error; fuse_put_request(fc, req); - if (!err) + + 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); + SetPageUptodate(page); + } + fuse_invalidate_attr(inode); /* atime changed */ out: unlock_page(page); @@ -439,8 +462,19 @@ static int fuse_readpage(struct file *fi static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) { int i; + size_t count = req->misc.read_in.size; + size_t num_read = req->out.args[0].size; + struct inode *inode = req->pages[0]->mapping->host; - fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */ + /* + * Short read means EOF. If file size is larger, truncate it + */ + if (!req->out.h.error && num_read < count) { + loff_t pos = page_offset(req->pages[0]) + num_read; + fuse_read_update_size(inode, pos); + } + + fuse_invalidate_attr(inode); /* atime changed */ for (i = 0; i < req->num_pages; i++) { struct page *page = req->pages[i]; -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/