From 253c9240ee09fd2a05d315ea44ac037a893d8981 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Tue, 9 Oct 2012 12:01:02 +0800 Subject: firmware loader: fix one reqeust_firmware race Several loading requests may be pending on one same firmware buf, and this patch moves fw_map_pages_buf() before complete_all(&fw_buf->completion) and let all requests see the mapped 'buf->data' once the loading is completed. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_class.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'drivers/base/firmware_class.c') diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index d06a8d0534bf..f2882511a9c1 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -423,6 +423,18 @@ static void firmware_free_data(const struct firmware *fw) #ifndef PAGE_KERNEL_RO #define PAGE_KERNEL_RO PAGE_KERNEL #endif + +/* one pages buffer should be mapped/unmapped only once */ +static int fw_map_pages_buf(struct firmware_buf *buf) +{ + if (buf->data) + vunmap(buf->data); + buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO); + if (!buf->data) + return -ENOMEM; + return 0; +} + /** * firmware_loading_store - set value in the 'loading' control file * @dev: device pointer @@ -467,6 +479,14 @@ static ssize_t firmware_loading_store(struct device *dev, if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) { set_bit(FW_STATUS_DONE, &fw_buf->status); clear_bit(FW_STATUS_LOADING, &fw_buf->status); + + /* + * Several loading requests may be pending on + * one same firmware buf, so let all requests + * see the mapped 'buf->data' once the loading + * is completed. + * */ + fw_map_pages_buf(fw_buf); complete_all(&fw_buf->completion); break; } @@ -670,15 +690,6 @@ exit: return fw_priv; } -/* one pages buffer is mapped/unmapped only once */ -static int fw_map_pages_buf(struct firmware_buf *buf) -{ - buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO); - if (!buf->data) - return -ENOMEM; - return 0; -} - /* store the pages buffer info firmware from buf */ static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw) { @@ -884,9 +895,6 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, if (!retval && f_dev->parent) fw_add_devm_name(f_dev->parent, buf->fw_id); - if (!retval) - retval = fw_map_pages_buf(buf); - /* * After caching firmware image is started, let it piggyback * on request firmware. -- cgit v1.2.1