diff --git a/fs/fuse/file.c b/fs/fuse/file.c index ba1d50369c24..8f39f7b8cef2 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1331,7 +1331,8 @@ EXPORT_SYMBOL_GPL(fuse_direct_io); static ssize_t __fuse_direct_read(struct fuse_io_priv *io, const struct iovec *iov, - unsigned long nr_segs, loff_t *ppos) + unsigned long nr_segs, loff_t *ppos, + size_t count) { ssize_t res; struct file *file = io->file; @@ -1340,8 +1341,7 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io, if (is_bad_inode(inode)) return -EIO; - res = fuse_direct_io(io, iov, nr_segs, iov_length(iov, nr_segs), - ppos, 0); + res = fuse_direct_io(io, iov, nr_segs, count, ppos, 0); fuse_invalidate_attr(inode); @@ -1353,7 +1353,7 @@ static ssize_t fuse_direct_read(struct file *file, char __user *buf, { struct fuse_io_priv io = { .async = 0, .file = file }; struct iovec iov = { .iov_base = buf, .iov_len = count }; - return __fuse_direct_read(&io, &iov, 1, ppos); + return __fuse_direct_read(&io, &iov, 1, ppos, count); } static ssize_t __fuse_direct_write(struct fuse_io_priv *io, @@ -2369,6 +2369,13 @@ fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, inode = file->f_mapping->host; i_size = i_size_read(inode); + /* optimization for short read */ + if (rw != WRITE && offset + count > i_size) { + if (offset >= i_size) + return 0; + count = i_size - offset; + } + io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL); if (!io) return -ENOMEM; @@ -2392,13 +2399,13 @@ fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, * to wait on real async I/O requests, so we must submit this request * synchronously. */ - if (!is_sync_kiocb(iocb) && (offset + count > i_size) && rw == WRITE) + if (!is_sync_kiocb(iocb) && (offset + count > i_size)) io->async = false; if (rw == WRITE) ret = __fuse_direct_write(io, iov, nr_segs, &pos); else - ret = __fuse_direct_read(io, iov, nr_segs, &pos); + ret = __fuse_direct_read(io, iov, nr_segs, &pos, count); if (io->async) { fuse_aio_complete(io, ret < 0 ? ret : 0, -1);