From 139aacf757fc89792c43a79ba99bc2361c98ecd3 Mon Sep 17 00:00:00 2001 From: Tomas Winkler Date: Wed, 29 May 2013 20:09:30 +0300 Subject: [PATCH] mei: fix read after read scenario mei read always has to be preceded by write but 'write write read read' scenario should work as well. In this case the offset is not zero but new read should be initiated Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/main.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c index b9ad510..5e11b5b 100644 --- a/drivers/misc/mei/main.c +++ b/drivers/misc/mei/main.c @@ -214,19 +214,21 @@ static ssize_t mei_read(struct file *file, char __user *ubuf, goto out; } - if (cl->read_cb && cl->read_cb->buf_idx > *offset) { - cb = cl->read_cb; - goto copy_buffer; - } else if (cl->read_cb && cl->read_cb->buf_idx > 0 && - cl->read_cb->buf_idx <= *offset) { + if (cl->read_cb) { cb = cl->read_cb; - rets = 0; - goto free; - } else if ((!cl->read_cb || !cl->read_cb->buf_idx) && *offset > 0) { - /*Offset needs to be cleaned for contiguous reads*/ + /* read what left */ + if (cb->buf_idx > *offset) + goto copy_buffer; + /* offset is beyond buf_idx we have no more data return 0 */ + if (cb->buf_idx > 0 && cb->buf_idx <= *offset) { + rets = 0; + goto free; + } + /* Offset needs to be cleaned for contiguous reads*/ + if (cb->buf_idx == 0 && *offset > 0) + *offset = 0; + } else if (*offset > 0) { *offset = 0; - rets = 0; - goto out; } err = mei_cl_read_start(cl, length); -- 2.7.4