From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3ySmSW20N0zDr8S for ; Fri, 3 Nov 2017 13:42:02 +1100 (AEDT) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vA32crnp125392 for ; Thu, 2 Nov 2017 22:41:59 -0400 Received: from e06smtp15.uk.ibm.com (e06smtp15.uk.ibm.com [195.75.94.111]) by mx0a-001b2d01.pphosted.com with ESMTP id 2e0de06mvc-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 02 Nov 2017 22:41:59 -0400 Received: from localhost by e06smtp15.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 3 Nov 2017 02:41:57 -0000 From: Cyril Bur To: linux-mtd@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, stewart@linux.vnet.ibm.com Cc: dwmw2@infradead.org, computersforpeace@gmail.com, boris.brezillon@free-electrons.com, sjitindarsingh@gmail.com Subject: [PATCH v5 04/10] mtd: powernv_flash: Don't return -ERESTARTSYS on interrupted token acquisition Date: Fri, 3 Nov 2017 13:41:40 +1100 In-Reply-To: <20171103024146.17086-1-cyrilbur@gmail.com> References: <20171103024146.17086-1-cyrilbur@gmail.com> Message-Id: <20171103024146.17086-5-cyrilbur@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Because the MTD core might split up a read() or write() from userspace into several calls to the driver, we may fail to get a token but already have done some work, best to return -EINTR back to userspace and have them decide what to do. Signed-off-by: Cyril Bur Acked-by: Boris Brezillon --- drivers/mtd/devices/powernv_flash.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/mtd/devices/powernv_flash.c b/drivers/mtd/devices/powernv_flash.c index 4dd3b5d2feb2..3343d4f5c4f3 100644 --- a/drivers/mtd/devices/powernv_flash.c +++ b/drivers/mtd/devices/powernv_flash.c @@ -47,6 +47,11 @@ enum flash_op { FLASH_OP_ERASE, }; +/* + * Don't return -ERESTARTSYS if we can't get a token, the MTD core + * might have split up the call from userspace and called into the + * driver more than once, we'll already have done some amount of work. + */ static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op, loff_t offset, size_t len, size_t *retlen, u_char *buf) { @@ -63,6 +68,8 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op, if (token < 0) { if (token != -ERESTARTSYS) dev_err(dev, "Failed to get an async token\n"); + else + token = -EINTR; return token; } -- 2.15.0