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 <adharmap@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index cc55788..f3b1445 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -59,6 +59,7 @@
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 afaf562..0b51190 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -561,6 +561,16 @@
}
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 @@
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;