From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754661AbbIKXhJ (ORCPT ); Fri, 11 Sep 2015 19:37:09 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:44241 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754586AbbIKXhI (ORCPT ); Fri, 11 Sep 2015 19:37:08 -0400 From: Stephen Boyd To: Mark Brown Cc: linux-kernel@vger.kernel.org, Abhijeet Dharmapurikar Subject: [PATCH v2] regmap: Allocate buffers with GFP_ATOMIC when fast_io == true Date: Fri, 11 Sep 2015 16:37:05 -0700 Message-Id: <1442014625-29560-1-git-send-email-sboyd@codeaurora.org> X-Mailer: git-send-email 2.3.0.rc1.33.g42e4583 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If a regmap is using fast_io, allocate the scratch buffer in regmap_bulk_write() with GFP_ATOMIC instead of GFP_KERNEL. Otherwise we may schedule while atomic. Reported-by: Abhijeet Dharmapurikar Signed-off-by: Stephen Boyd --- Changes since v1: * Only modify allocations in regmap_bulk_write() path drivers/base/regmap/internal.h | 1 + drivers/base/regmap/regmap.c | 12 +++++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h index 873ddf91c9d3..3470ec146f12 100644 --- a/drivers/base/regmap/internal.h +++ b/drivers/base/regmap/internal.h @@ -59,6 +59,7 @@ struct regmap { regmap_lock lock; regmap_unlock unlock; void *lock_arg; /* This is passed to lock/unlock functions */ + gfp_t alloc_flags; struct device *dev; /* Device we do I/O on */ void *work_buf; /* Scratch buffer used to format I/O */ diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 29128c6af445..dc90f2ac332a 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -563,6 +563,16 @@ struct regmap *regmap_init(struct device *dev, } map->lock_arg = map; } + + /* + * When we write in fast-paths with regmap_bulk_write() don't allocate + * scratch buffers with sleeping allocations. + */ + if ((bus && bus->fast_io) || config->fast_io) + map->alloc_flags = GFP_ATOMIC; + else + map->alloc_flags = GFP_KERNEL; + map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8); map->format.pad_bytes = config->pad_bits / 8; map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8); @@ -1729,7 +1739,7 @@ out: if (!val_count) return -EINVAL; - wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL); + wval = kmemdup(val, val_count * val_bytes, map->alloc_flags); if (!wval) { dev_err(map->dev, "Error in memory allocation\n"); return -ENOMEM; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project