mei: simplify io callback disposal

Simplify disposal of io callback by removing the callback
implicitly from its lookup list inside mei_io_cb_free

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

6 files changed, 63 insertions, 105 deletions

diff --git a/drivers/misc/mei/amthif.c b/drivers/misc/mei/amthif.c
index 3fdd22395b9f..7b6ed0bbfc9c 100644
--- a/drivers/misc/mei/amthif.c
+++ b/drivers/misc/mei/amthif.c
@@ -196,16 +196,16 @@ int mei_amthif_read(struct mei_device *dev, struct file *file,
         if  (time_after(jiffies, timeout)) {
                 dev_dbg(dev->dev, "amthif Time out\n");
                 /* 15 sec for the message has expired */
-                list_del(&cb->list);
+                list_del_init(&cb->list);
                 rets = -ETIME;
                 goto free;
         }
         /* if the whole message will fit remove it from the list */
         if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
-                list_del(&cb->list);
+                list_del_init(&cb->list);
         else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
                 /* end of the message has been reached */
-                list_del(&cb->list);
+                list_del_init(&cb->list);
                 rets = 0;
                 goto free;
         }
@@ -504,26 +504,22 @@ void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 static bool mei_clear_list(struct mei_device *dev,
                 const struct file *file, struct list_head *mei_cb_list)
 {
-        struct mei_cl_cb *cb_pos = NULL;
-        struct mei_cl_cb *cb_next = NULL;
+        struct mei_cl *cl = &dev->iamthif_cl;
+        struct mei_cl_cb *cb, *next;
         bool removed = false;
 
         /* list all list member */
-        list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
+        list_for_each_entry_safe(cb, next, mei_cb_list, list) {
                 /* check if list member associated with a file */
-                if (file == cb_pos->file_object) {
-                        /* remove member from the list */
-                        list_del(&cb_pos->list);
+                if (file == cb->file_object) {
                         /* check if cb equal to current iamthif cb */
-                        if (dev->iamthif_current_cb == cb_pos) {
+                        if (dev->iamthif_current_cb == cb) {
                                 dev->iamthif_current_cb = NULL;
                                 /* send flow control to iamthif client */
-                                mei_hbm_cl_flow_control_req(dev,
-                                                        &dev->iamthif_cl);
+                                mei_hbm_cl_flow_control_req(dev, cl);
                         }
                         /* free all allocated buffers */
-                        mei_io_cb_free(cb_pos);
-                        cb_pos = NULL;
+                        mei_io_cb_free(cb);
                         removed = true;
                 }
         }
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index 3e6ffed9402a..b5385372693d 100644
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -311,13 +311,13 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
                 mutex_lock(&dev->device_lock);
         }
 
-        cb = cl->read_cb;
 
         if (cl->reading_state != MEI_READ_COMPLETE) {
                 rets = 0;
                 goto out;
         }
 
+        cb = cl->read_cb;
         if (cb->status) {
                 rets = cb->status;
                 goto free;
@@ -329,8 +329,8 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 
 free:
         mei_io_cb_free(cb);
-        cl->reading_state = MEI_IDLE;
         cl->read_cb = NULL;
+        cl->reading_state = MEI_IDLE;
 
 out:
         mutex_unlock(&dev->device_lock);
@@ -486,23 +486,7 @@ int mei_cl_disable_device(struct mei_cl_device *device)
 
         /* Flush queues and remove any pending read */
         mei_cl_flush_queues(cl);
-
-        if (cl->read_cb) {
-                struct mei_cl_cb *cb = NULL;
-
-                cb = mei_cl_find_read_cb(cl);
-                /* Remove entry from read list */
-                if (cb)
-                        list_del(&cb->list);
-
-                cb = cl->read_cb;
-                cl->read_cb = NULL;
-
-                if (cb) {
-                        mei_io_cb_free(cb);
-                        cb = NULL;
-                }
-        }
+        mei_io_cb_free(cl->read_cb);
 
         device->event_cb = NULL;
 
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index e263c0713a6d..624bf0182a50 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -321,6 +321,47 @@ static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 }
 
 /**
+ * mei_io_cb_free - free mei_cb_private related memory
+ *
+ * @cb: mei callback struct
+ */
+void mei_io_cb_free(struct mei_cl_cb *cb)
+{
+        if (cb == NULL)
+                return;
+
+        list_del(&cb->list);
+        kfree(cb->buf.data);
+        kfree(cb);
+}
+
+/**
+ * mei_io_cb_init - allocate and initialize io callback
+ *
+ * @cl: mei client
+ * @type: operation type
+ * @fp: pointer to file structure
+ *
+ * Return: mei_cl_cb pointer or NULL;
+ */
+struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
+                                 struct file *fp)
+{
+        struct mei_cl_cb *cb;
+
+        cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+        if (!cb)
+                return NULL;
+
+        INIT_LIST_HEAD(&cb->list);
+        cb->file_object = fp;
+        cb->cl = cl;
+        cb->buf_idx = 0;
+        cb->fop_type = type;
+        return cb;
+}
+
+/**
  * __mei_io_list_flush - removes and frees cbs belonging to cl.
  *
  * @list:  an instance of our list structure
@@ -330,13 +371,12 @@ static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 static void __mei_io_list_flush(struct mei_cl_cb *list,
                                 struct mei_cl *cl, bool free)
 {
-        struct mei_cl_cb *cb;
-        struct mei_cl_cb *next;
+        struct mei_cl_cb *cb, *next;
 
         /* enable removing everything if no cl is specified */
         list_for_each_entry_safe(cb, next, &list->list, list) {
                 if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
-                        list_del(&cb->list);
+                        list_del_init(&cb->list);
                         if (free)
                                 mei_io_cb_free(cb);
                 }
@@ -354,7 +394,6 @@ void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
         __mei_io_list_flush(list, cl, false);
 }
 
-
 /**
  * mei_io_list_free - removes cb belonging to cl and free them
  *
@@ -367,47 +406,6 @@ static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 }
 
 /**
- * mei_io_cb_free - free mei_cb_private related memory
- *
- * @cb: mei callback struct
- */
-void mei_io_cb_free(struct mei_cl_cb *cb)
-{
-        if (cb == NULL)
-                return;
-
-        kfree(cb->buf.data);
-        kfree(cb);
-}
-
-/**
- * mei_io_cb_init - allocate and initialize io callback
- *
- * @cl: mei client
- * @type: operation type
- * @fp: pointer to file structure
- *
- * Return: mei_cl_cb pointer or NULL;
- */
-struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
-                                 struct file *fp)
-{
-        struct mei_cl_cb *cb;
-
-        cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
-        if (!cb)
-                return NULL;
-
-        mei_io_list_init(cb);
-
-        cb->file_object = fp;
-        cb->cl = cl;
-        cb->buf_idx = 0;
-        cb->fop_type = type;
-        return cb;
-}
-
-/**
  * mei_io_cb_alloc_buf - allocate callback buffer
  *
  * @cb: io callback structure
diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index 2c581dcaf3b1..58da92565c5e 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -639,7 +639,7 @@ static void mei_hbm_cl_res(struct mei_device *dev,
                         continue;
 
                 if (mei_hbm_cl_addr_equal(cl, rs)) {
-                        list_del(&cb->list);
+                        list_del_init(&cb->list);
                         break;
                 }
         }
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 60469a0053bb..1e2f3c774853 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -202,7 +202,6 @@ static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 
         cl->state = MEI_FILE_DISCONNECTED;
         cl->status = 0;
-        list_del(&cb->list);
         mei_io_cb_free(cb);
 
         return ret;
@@ -320,7 +319,7 @@ static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
         if (ret) {
                 cl->status = ret;
                 cb->buf_idx = 0;
-                list_del(&cb->list);
+                list_del_init(&cb->list);
                 return ret;
         }
 
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index 10fc3a6a1574..c34853be963f 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -94,7 +94,6 @@ err_unlock:
 static int mei_release(struct inode *inode, struct file *file)
 {
         struct mei_cl *cl = file->private_data;
-        struct mei_cl_cb *cb;
         struct mei_device *dev;
         int rets = 0;
 
@@ -118,23 +117,11 @@ static int mei_release(struct inode *inode, struct file *file)
 
         mei_cl_unlink(cl);
 
-
-        /* free read cb */
-        cb = NULL;
-        if (cl->read_cb) {
-                cb = mei_cl_find_read_cb(cl);
-                /* Remove entry from read list */
-                if (cb)
-                        list_del(&cb->list);
-
-                cb = cl->read_cb;
-                cl->read_cb = NULL;
-        }
+        mei_io_cb_free(cl->read_cb);
+        cl->read_cb = NULL;
 
         file->private_data = NULL;
 
-        mei_io_cb_free(cb);
-
         kfree(cl);
 out:
         mutex_unlock(&dev->device_lock);
@@ -156,7 +143,6 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
                         size_t length, loff_t *offset)
 {
         struct mei_cl *cl = file->private_data;
-        struct mei_cl_cb *cb_pos = NULL;
         struct mei_cl_cb *cb = NULL;
         struct mei_device *dev;
         int rets;
@@ -279,13 +265,10 @@ copy_buffer:
                 goto out;
 
 free:
-        cb_pos = mei_cl_find_read_cb(cl);
-        /* Remove entry from read list */
-        if (cb_pos)
-                list_del(&cb_pos->list);
         mei_io_cb_free(cb);
-        cl->reading_state = MEI_IDLE;
         cl->read_cb = NULL;
+
+        cl->reading_state = MEI_IDLE;
 out:
         dev_dbg(dev->dev, "end mei read rets= %d\n", rets);
         mutex_unlock(&dev->device_lock);
@@ -355,7 +338,6 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
                         if (time_after(jiffies, timeout) ||
                             cl->reading_state == MEI_READ_COMPLETE) {
                                 *offset = 0;
-                                list_del(&write_cb->list);
                                 mei_io_cb_free(write_cb);
                                 write_cb = NULL;
                         }
@@ -367,11 +349,10 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
                 *offset = 0;
                 write_cb = mei_cl_find_read_cb(cl);
                 if (write_cb) {
-                        list_del(&write_cb->list);
                         mei_io_cb_free(write_cb);
                         write_cb = NULL;
-                        cl->reading_state = MEI_IDLE;
                         cl->read_cb = NULL;
+                        cl->reading_state = MEI_IDLE;
                 }
         } else if (cl->reading_state == MEI_IDLE)
                 *offset = 0;