2 files changed, 41 insertions, 85 deletions

diff --git a/drivers/net/wireless/ath/ath6kl/core.h b/drivers/net/wireless/ath/ath6kl/core.h
index c4d66e066dc9..9a58214135b9 100644
--- a/drivers/net/wireless/ath/ath6kl/core.h
+++ b/drivers/net/wireless/ath/ath6kl/core.h
@@ -652,10 +652,9 @@ struct ath6kl {
 
 #ifdef CONFIG_ATH6KL_DEBUG
         struct {
-                struct circ_buf fwlog_buf;
-                spinlock_t fwlog_lock;
-                void *fwlog_tmp;
+                struct sk_buff_head fwlog_queue;
                 u32 fwlog_mask;
+
                 unsigned int dbgfs_diag_reg;
                 u32 diag_reg_addr_wr;
                 u32 diag_reg_val_wr;
diff --git a/drivers/net/wireless/ath/ath6kl/debug.c b/drivers/net/wireless/ath/ath6kl/debug.c
index d832058816fe..98b5f15f622e 100644
--- a/drivers/net/wireless/ath/ath6kl/debug.c
+++ b/drivers/net/wireless/ath/ath6kl/debug.c
@@ -16,7 +16,7 @@
 
 #include "core.h"
 
-#include <linux/circ_buf.h>
+#include <linux/skbuff.h>
 #include <linux/fs.h>
 #include <linux/vmalloc.h>
 #include <linux/export.h>
@@ -32,9 +32,8 @@ struct ath6kl_fwlog_slot {
         u8 payload[0];
 };
 
-#define ATH6KL_FWLOG_SIZE 32768
-#define ATH6KL_FWLOG_SLOT_SIZE (sizeof(struct ath6kl_fwlog_slot) + \
-                                ATH6KL_FWLOG_PAYLOAD_SIZE)
+#define ATH6KL_FWLOG_MAX_ENTRIES 20
+
 #define ATH6KL_FWLOG_VALID_MASK 0x1ffff
 
 int ath6kl_printk(const char *level, const char *fmt, ...)
@@ -268,105 +267,77 @@ static const struct file_operations fops_war_stats = {
         .llseek = default_llseek,
 };
 
-static void ath6kl_debug_fwlog_add(struct ath6kl *ar, const void *buf,
-                                   size_t buf_len)
-{
-        struct circ_buf *fwlog = &ar->debug.fwlog_buf;
-        size_t space;
-        int i;
-
-        /* entries must all be equal size */
-        if (WARN_ON(buf_len != ATH6KL_FWLOG_SLOT_SIZE))
-                return;
-
-        space = CIRC_SPACE(fwlog->head, fwlog->tail, ATH6KL_FWLOG_SIZE);
-        if (space < buf_len)
-                /* discard oldest slot */
-                fwlog->tail = (fwlog->tail + ATH6KL_FWLOG_SLOT_SIZE) &
-                        (ATH6KL_FWLOG_SIZE - 1);
-
-        for (i = 0; i < buf_len; i += space) {
-                space = CIRC_SPACE_TO_END(fwlog->head, fwlog->tail,
-                                          ATH6KL_FWLOG_SIZE);
-
-                if ((size_t) space > buf_len - i)
-                        space = buf_len - i;
-
-                memcpy(&fwlog->buf[fwlog->head], buf, space);
-                fwlog->head = (fwlog->head + space) & (ATH6KL_FWLOG_SIZE - 1);
-        }
-
-}
-
 void ath6kl_debug_fwlog_event(struct ath6kl *ar, const void *buf, size_t len)
 {
-        struct ath6kl_fwlog_slot *slot = ar->debug.fwlog_tmp;
+        struct ath6kl_fwlog_slot *slot;
+        struct sk_buff *skb;
         size_t slot_len;
 
         if (WARN_ON(len > ATH6KL_FWLOG_PAYLOAD_SIZE))
                 return;
 
-        spin_lock_bh(&ar->debug.fwlog_lock);
+        slot_len = sizeof(*slot) + len;
 
+        skb = alloc_skb(slot_len, GFP_KERNEL);
+        if (!skb)
+                return;
+
+        slot = (struct ath6kl_fwlog_slot *) skb_put(skb, slot_len);
         slot->timestamp = cpu_to_le32(jiffies);
         slot->length = cpu_to_le32(len);
         memcpy(slot->payload, buf, len);
 
-        slot_len = sizeof(*slot) + len;
+        spin_lock(&ar->debug.fwlog_queue.lock);
 
-        if (slot_len < ATH6KL_FWLOG_SLOT_SIZE)
-                memset(slot->payload + len, 0,
-                       ATH6KL_FWLOG_SLOT_SIZE - slot_len);
+        __skb_queue_tail(&ar->debug.fwlog_queue, skb);
 
-        ath6kl_debug_fwlog_add(ar, slot, ATH6KL_FWLOG_SLOT_SIZE);
+        /* drop oldest entries */
+        while (skb_queue_len(&ar->debug.fwlog_queue) >
+               ATH6KL_FWLOG_MAX_ENTRIES) {
+                skb = __skb_dequeue(&ar->debug.fwlog_queue);
+                kfree_skb(skb);
+        }
 
-        spin_unlock_bh(&ar->debug.fwlog_lock);
-}
+        spin_unlock(&ar->debug.fwlog_queue.lock);
 
-static bool ath6kl_debug_fwlog_empty(struct ath6kl *ar)
-{
-        return CIRC_CNT(ar->debug.fwlog_buf.head,
-                        ar->debug.fwlog_buf.tail,
-                        ATH6KL_FWLOG_SLOT_SIZE) == 0;
+        return;
 }
 
 static ssize_t ath6kl_fwlog_read(struct file *file, char __user *user_buf,
                                  size_t count, loff_t *ppos)
 {
         struct ath6kl *ar = file->private_data;
-        struct circ_buf *fwlog = &ar->debug.fwlog_buf;
-        size_t len = 0, buf_len = count;
+        struct sk_buff *skb;
         ssize_t ret_cnt;
+        size_t len = 0;
         char *buf;
-        int ccnt;
 
-        buf = vmalloc(buf_len);
+        buf = vmalloc(count);
         if (!buf)
                 return -ENOMEM;
 
         /* read undelivered logs from firmware */
         ath6kl_read_fwlogs(ar);
 
-        spin_lock_bh(&ar->debug.fwlog_lock);
+        spin_lock(&ar->debug.fwlog_queue.lock);
 
-        while (len < buf_len && !ath6kl_debug_fwlog_empty(ar)) {
-                ccnt = CIRC_CNT_TO_END(fwlog->head, fwlog->tail,
-                                       ATH6KL_FWLOG_SIZE);
+        while ((skb = __skb_dequeue(&ar->debug.fwlog_queue))) {
+                if (skb->len > count - len) {
+                        /* not enough space, put skb back and leave */
+                        __skb_queue_head(&ar->debug.fwlog_queue, skb);
+                        break;
+                }
 
-                if ((size_t) ccnt > buf_len - len)
-                        ccnt = buf_len - len;
 
-                memcpy(buf + len, &fwlog->buf[fwlog->tail], ccnt);
-                len += ccnt;
+                memcpy(buf + len, skb->data, skb->len);
+                len += skb->len;
 
-                fwlog->tail = (fwlog->tail + ccnt) &
-                        (ATH6KL_FWLOG_SIZE - 1);
+                kfree_skb(skb);
         }
 
-        spin_unlock_bh(&ar->debug.fwlog_lock);
+        spin_unlock(&ar->debug.fwlog_queue.lock);
 
-        if (WARN_ON(len > buf_len))
-                len = buf_len;
+        /* FIXME: what to do if len == 0? */
 
         ret_cnt = simple_read_from_buffer(user_buf, count, ppos, buf, len);
 
@@ -1651,17 +1622,7 @@ static const struct file_operations fops_power_params = {
 
 int ath6kl_debug_init(struct ath6kl *ar)
 {
-        ar->debug.fwlog_buf.buf = vmalloc(ATH6KL_FWLOG_SIZE);
-        if (ar->debug.fwlog_buf.buf == NULL)
-                return -ENOMEM;
-
-        ar->debug.fwlog_tmp = kmalloc(ATH6KL_FWLOG_SLOT_SIZE, GFP_KERNEL);
-        if (ar->debug.fwlog_tmp == NULL) {
-                vfree(ar->debug.fwlog_buf.buf);
-                return -ENOMEM;
-        }
-
-        spin_lock_init(&ar->debug.fwlog_lock);
+        skb_queue_head_init(&ar->debug.fwlog_queue);
 
         /*
          * Actually we are lying here but don't know how to read the mask
@@ -1671,11 +1632,8 @@ int ath6kl_debug_init(struct ath6kl *ar)
 
         ar->debugfs_phy = debugfs_create_dir("ath6kl",
                                              ar->wiphy->debugfsdir);
-        if (!ar->debugfs_phy) {
-                vfree(ar->debug.fwlog_buf.buf);
-                kfree(ar->debug.fwlog_tmp);
+        if (!ar->debugfs_phy)
                 return -ENOMEM;
-        }
 
         debugfs_create_file("tgt_stats", S_IRUSR, ar->debugfs_phy, ar,
                             &fops_tgt_stats);
@@ -1742,8 +1700,7 @@ int ath6kl_debug_init(struct ath6kl *ar)
 
 void ath6kl_debug_cleanup(struct ath6kl *ar)
 {
-        vfree(ar->debug.fwlog_buf.buf);
-        kfree(ar->debug.fwlog_tmp);
+        skb_queue_purge(&ar->debug.fwlog_queue);
         kfree(ar->debug.roam_tbl);
 }