Merge tag 'iwlwifi-for-kalle-2016-06-10' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / block / blk-sysfs.c

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 995b58d..9920596 100644 (file)
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -347,6 +347,38 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page,
        return ret;
 }
 
+static ssize_t queue_wc_show(struct request_queue *q, char *page)
+{
+       if (test_bit(QUEUE_FLAG_WC, &q->queue_flags))
+               return sprintf(page, "write back\n");
+
+       return sprintf(page, "write through\n");
+}
+
+static ssize_t queue_wc_store(struct request_queue *q, const char *page,
+                             size_t count)
+{
+       int set = -1;
+
+       if (!strncmp(page, "write back", 10))
+               set = 1;
+       else if (!strncmp(page, "write through", 13) ||
+                !strncmp(page, "none", 4))
+               set = 0;
+
+       if (set == -1)
+               return -EINVAL;
+
+       spin_lock_irq(q->queue_lock);
+       if (set)
+               queue_flag_set(QUEUE_FLAG_WC, q);
+       else
+               queue_flag_clear(QUEUE_FLAG_WC, q);
+       spin_unlock_irq(q->queue_lock);
+
+       return count;
+}
+
 static struct queue_sysfs_entry queue_requests_entry = {
        .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
        .show = queue_requests_show,
@@ -478,6 +510,12 @@ static struct queue_sysfs_entry queue_poll_entry = {
        .store = queue_poll_store,
 };
 
+static struct queue_sysfs_entry queue_wc_entry = {
+       .attr = {.name = "write_cache", .mode = S_IRUGO | S_IWUSR },
+       .show = queue_wc_show,
+       .store = queue_wc_store,
+};
+
 static struct attribute *default_attrs[] = {
        &queue_requests_entry.attr,
        &queue_ra_entry.attr,
@@ -503,6 +541,7 @@ static struct attribute *default_attrs[] = {
        &queue_iostats_entry.attr,
        &queue_random_entry.attr,
        &queue_poll_entry.attr,
+       &queue_wc_entry.attr,
        NULL,
 };