From 56fb1c74f3bda1c0100fc3e9a7888c229174f9a4 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 18 Mar 2014 10:53:26 +0000 Subject: [PATCH] regmap: Ensure regmap_register_patch() is compatible with fast_io With fast_io we use mutexes to lock the I/O operations so we would need to do GFP_ATOMIC allocations if we wanted to do allocations inside the lock as we do currently. Since it is unlikely that we will want to register a patch outside of init where concurrency shouldn't be an issue move the allocation of the patch data outside the lock. Reported-by: Takashi Iwai Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 6a19515f8a45..e5a5509160fe 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2173,6 +2173,9 @@ EXPORT_SYMBOL_GPL(regmap_async_complete); * apply them immediately. Typically this is used to apply * corrections to be applied to the device defaults on startup, such * as the updates some vendors provide to undocumented registers. + * + * The caller must ensure that this function cannot be called + * concurrently with either itself or regcache_sync(). */ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, int num_regs) @@ -2185,6 +2188,17 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, num_regs)) return 0; + p = krealloc(map->patch, + sizeof(struct reg_default) * (map->patch_regs + num_regs), + GFP_KERNEL); + if (p) { + memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs)); + map->patch = p; + map->patch_regs += num_regs; + } else { + return -ENOMEM; + } + map->lock(map->lock_arg); bypass = map->cache_bypass; @@ -2202,17 +2216,6 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, } } - p = krealloc(map->patch, - sizeof(struct reg_default) * (map->patch_regs + num_regs), - GFP_KERNEL); - if (p) { - memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs)); - map->patch = p; - map->patch_regs += num_regs; - } else { - ret = -ENOMEM; - } - out: map->async = false; map->cache_bypass = bypass; -- 2.34.1