Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

[karo-tx-linux.git] / net / mac80211 / debugfs.c

diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 5c090e41d9bbf1ea379307c8ecd6a648cb33f0ac..fa16e54980a1d3e76ce2f85fcb3253eb2599e838 100644 (file)
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -17,6 +17,172 @@
 
 #define DEBUGFS_FORMAT_BUFFER_SIZE 100
 
+#define TX_LATENCY_BIN_DELIMTER_C ','
+#define TX_LATENCY_BIN_DELIMTER_S ","
+#define TX_LATENCY_BINS_DISABLED "enable(bins disabled)\n"
+#define TX_LATENCY_DISABLED "disable\n"
+
+
+/*
+ * Display if Tx latency statistics & bins are enabled/disabled
+ */
+static ssize_t sta_tx_latency_stat_read(struct file *file,
+                                       char __user *userbuf,
+                                       size_t count, loff_t *ppos)
+{
+       struct ieee80211_local *local = file->private_data;
+       struct ieee80211_tx_latency_bin_ranges  *tx_latency;
+       char *buf;
+       int bufsz, i, ret;
+       int pos = 0;
+
+       rcu_read_lock();
+
+       tx_latency = rcu_dereference(local->tx_latency);
+
+       if (tx_latency && tx_latency->n_ranges) {
+               bufsz = tx_latency->n_ranges * 15;
+               buf = kzalloc(bufsz, GFP_ATOMIC);
+               if (!buf)
+                       goto err;
+
+               for (i = 0; i < tx_latency->n_ranges; i++)
+                       pos += scnprintf(buf + pos, bufsz - pos, "%d,",
+                                        tx_latency->ranges[i]);
+               pos += scnprintf(buf + pos, bufsz - pos, "\n");
+       } else if (tx_latency) {
+               bufsz = sizeof(TX_LATENCY_BINS_DISABLED) + 1;
+               buf = kzalloc(bufsz, GFP_ATOMIC);
+               if (!buf)
+                       goto err;
+
+               pos += scnprintf(buf + pos, bufsz - pos, "%s\n",
+                                TX_LATENCY_BINS_DISABLED);
+       } else {
+               bufsz = sizeof(TX_LATENCY_DISABLED) + 1;
+               buf = kzalloc(bufsz, GFP_ATOMIC);
+               if (!buf)
+                       goto err;
+
+               pos += scnprintf(buf + pos, bufsz - pos, "%s\n",
+                                TX_LATENCY_DISABLED);
+       }
+
+       rcu_read_unlock();
+
+       ret = simple_read_from_buffer(userbuf, count, ppos, buf, pos);
+       kfree(buf);
+
+       return ret;
+err:
+       rcu_read_unlock();
+       return -ENOMEM;
+}
+
+/*
+ * Receive input from user regarding Tx latency statistics
+ * The input should indicate if Tx latency statistics and bins are
+ * enabled/disabled.
+ * If bins are enabled input should indicate the amount of different bins and
+ * their ranges. Each bin will count how many Tx frames transmitted within the
+ * appropriate latency.
+ * Legal input is:
+ * a) "enable(bins disabled)" - to enable only general statistics
+ * b) "a,b,c,d,...z" - to enable general statistics and bins, where all are
+ * numbers and a < b < c < d.. < z
+ * c) "disable" - disable all statistics
+ * NOTE: must configure Tx latency statistics bins before stations connected.
+ */
+
+static ssize_t sta_tx_latency_stat_write(struct file *file,
+                                        const char __user *userbuf,
+                                        size_t count, loff_t *ppos)
+{
+       struct ieee80211_local *local = file->private_data;
+       char buf[128] = {};
+       char *bins = buf;
+       char *token;
+       int buf_size, i, alloc_size;
+       int prev_bin = 0;
+       int n_ranges = 0;
+       int ret = count;
+       struct ieee80211_tx_latency_bin_ranges  *tx_latency;
+
+       if (sizeof(buf) <= count)
+               return -EINVAL;
+       buf_size = count;
+       if (copy_from_user(buf, userbuf, buf_size))
+               return -EFAULT;
+
+       mutex_lock(&local->sta_mtx);
+
+       /* cannot change config once we have stations */
+       if (local->num_sta)
+               goto unlock;
+
+       tx_latency =
+               rcu_dereference_protected(local->tx_latency,
+                                         lockdep_is_held(&local->sta_mtx));
+
+       /* disable Tx statistics */
+       if (!strcmp(buf, TX_LATENCY_DISABLED)) {
+               if (!tx_latency)
+                       goto unlock;
+               rcu_assign_pointer(local->tx_latency, NULL);
+               synchronize_rcu();
+               kfree(tx_latency);
+               goto unlock;
+       }
+
+       /* Tx latency already enabled */
+       if (tx_latency)
+               goto unlock;
+
+       if (strcmp(TX_LATENCY_BINS_DISABLED, buf)) {
+               /* check how many bins and between what ranges user requested */
+               token = buf;
+               while (*token != '\0') {
+                       if (*token == TX_LATENCY_BIN_DELIMTER_C)
+                               n_ranges++;
+                       token++;
+               }
+               n_ranges++;
+       }
+
+       alloc_size = sizeof(struct ieee80211_tx_latency_bin_ranges) +
+                    n_ranges * sizeof(u32);
+       tx_latency = kzalloc(alloc_size, GFP_ATOMIC);
+       if (!tx_latency) {
+               ret = -ENOMEM;
+               goto unlock;
+       }
+       tx_latency->n_ranges = n_ranges;
+       for (i = 0; i < n_ranges; i++) { /* setting bin ranges */
+               token = strsep(&bins, TX_LATENCY_BIN_DELIMTER_S);
+               sscanf(token, "%d", &tx_latency->ranges[i]);
+               /* bins values should be in ascending order */
+               if (prev_bin >= tx_latency->ranges[i]) {
+                       ret = -EINVAL;
+                       kfree(tx_latency);
+                       goto unlock;
+               }
+               prev_bin = tx_latency->ranges[i];
+       }
+       rcu_assign_pointer(local->tx_latency, tx_latency);
+
+unlock:
+       mutex_unlock(&local->sta_mtx);
+
+       return ret;
+}
+
+static const struct file_operations stats_tx_latency_ops = {
+       .write = sta_tx_latency_stat_write,
+       .read = sta_tx_latency_stat_read,
+       .open = simple_open,
+       .llseek = generic_file_llseek,
+};
+
 int mac80211_format_buffer(char __user *userbuf, size_t count,
                                  loff_t *ppos, char *fmt, ...)
 {
@@ -315,4 +481,6 @@ void debugfs_hw_add(struct ieee80211_local *local)
        DEBUGFS_DEVSTATS_ADD(dot11RTSFailureCount);
        DEBUGFS_DEVSTATS_ADD(dot11FCSErrorCount);
        DEBUGFS_DEVSTATS_ADD(dot11RTSSuccessCount);
+
+       DEBUGFS_DEVSTATS_ADD(tx_latency);
 }