From 1c1813a743fe84d0dcf53743baa4edc1f74c44c8 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Thu, 3 Feb 2022 15:32:15 +0100 Subject: [PATCH] HID: core: statically allocate read buffers This is a preparation patch for rethinking the generic processing of HID reports. We can actually pre-allocate all of our memory instead of dynamically allocating/freeing it whenever we parse a report. Signed-off-by: Benjamin Tissoires Reviewed-by: Ping Cheng Acked-by: Peter Hutterer Signed-off-by: Jiri Kosina --- drivers/hid/hid-core.c | 12 +++++------- include/linux/hid.h | 1 + 2 files changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index f1aed5bbd000..75e7b8447bf7 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -101,7 +101,7 @@ static struct hid_field *hid_register_field(struct hid_report *report, unsigned field = kzalloc((sizeof(struct hid_field) + usages * sizeof(struct hid_usage) + - usages * sizeof(unsigned)), GFP_KERNEL); + 2 * usages * sizeof(unsigned int)), GFP_KERNEL); if (!field) return NULL; @@ -109,6 +109,7 @@ static struct hid_field *hid_register_field(struct hid_report *report, unsigned report->field[field->index] = field; field->usage = (struct hid_usage *)(field + 1); field->value = (s32 *)(field->usage + usages); + field->new_value = (s32 *)(field->value + usages); field->report = report; return field; @@ -1541,9 +1542,8 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, __s32 max = field->logical_maximum; __s32 *value; - value = kmalloc_array(count, sizeof(__s32), GFP_ATOMIC); - if (!value) - return; + value = field->new_value; + memset(value, 0, count * sizeof(__s32)); for (n = 0; n < count; n++) { @@ -1557,7 +1557,7 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, value[n] >= min && value[n] <= max && value[n] - min < field->maxusage && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) - goto exit; + return; } for (n = 0; n < count; n++) { @@ -1581,8 +1581,6 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, } memcpy(field->value, value, count * sizeof(__s32)); -exit: - kfree(value); } /* diff --git a/include/linux/hid.h b/include/linux/hid.h index 7487b0586fe6..3fbfe0986659 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -476,6 +476,7 @@ struct hid_field { unsigned report_count; /* number of this field in the report */ unsigned report_type; /* (input,output,feature) */ __s32 *value; /* last known value(s) */ + __s32 *new_value; /* newly read value(s) */ __s32 logical_minimum; __s32 logical_maximum; __s32 physical_minimum; -- 2.11.0