From b4a21fc275e99fc63c77b30da92ee497f8a7bdb6 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Fri, 11 Sep 2015 16:37:05 -0700 Subject: [PATCH] regmap: Allocate buffers with GFP_ATOMIC when fast_io == true 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 Signed-off-by: Mark Brown --- 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 cc557886ab23..f3b1445da0a5 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 afaf56200674..0b51190c13df 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -561,6 +561,16 @@ 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); @@ -1786,7 +1796,7 @@ 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; -- 2.30.2