IB: refcount race fixes

[powerpc.git] / drivers / infiniband / core / ucm.c

diff --git a/drivers/infiniband/core/ucm.c b/drivers/infiniband/core/ucm.c
index 6e15787..9164a09 100644 (file)
--- a/drivers/infiniband/core/ucm.c
+++ b/drivers/infiniband/core/ucm.c
@@ -32,6 +32,8 @@
  *
  * $Id: ucm.c 2594 2005-06-13 19:46:02Z libor $
  */
+
+#include <linux/completion.h>
 #include <linux/init.h>
 #include <linux/fs.h>
 #include <linux/module.h>
@@ -42,6 +44,7 @@
 #include <linux/mount.h>
 #include <linux/cdev.h>
 #include <linux/idr.h>
+#include <linux/mutex.h>
 
 #include <asm/uaccess.h>
 
@@ -71,7 +74,7 @@ struct ib_ucm_file {
 
 struct ib_ucm_context {
        int                 id;
-       wait_queue_head_t   wait;
+       struct completion   comp;
        atomic_t            ref;
        int                 events_reported;
 
@@ -113,7 +116,7 @@ static struct ib_client ucm_client = {
        .remove = ib_ucm_remove_one
 };
 
-static DECLARE_MUTEX(ctx_id_mutex);
+static DEFINE_MUTEX(ctx_id_mutex);
 static DEFINE_IDR(ctx_id_table);
 static DECLARE_BITMAP(dev_map, IB_UCM_MAX_DEVICES);
 
@@ -121,7 +124,7 @@ static struct ib_ucm_context *ib_ucm_ctx_get(struct ib_ucm_file *file, int id)
 {
        struct ib_ucm_context *ctx;
 
-       down(&ctx_id_mutex);
+       mutex_lock(&ctx_id_mutex);
        ctx = idr_find(&ctx_id_table, id);
        if (!ctx)
                ctx = ERR_PTR(-ENOENT);
@@ -129,7 +132,7 @@ static struct ib_ucm_context *ib_ucm_ctx_get(struct ib_ucm_file *file, int id)
                ctx = ERR_PTR(-EINVAL);
        else
                atomic_inc(&ctx->ref);
-       up(&ctx_id_mutex);
+       mutex_unlock(&ctx_id_mutex);
 
        return ctx;
 }
@@ -137,7 +140,7 @@ static struct ib_ucm_context *ib_ucm_ctx_get(struct ib_ucm_file *file, int id)
 static void ib_ucm_ctx_put(struct ib_ucm_context *ctx)
 {
        if (atomic_dec_and_test(&ctx->ref))
-               wake_up(&ctx->wait);
+               complete(&ctx->comp);
 }
 
 static inline int ib_ucm_new_cm_id(int event)
@@ -177,7 +180,7 @@ static struct ib_ucm_context *ib_ucm_ctx_alloc(struct ib_ucm_file *file)
                return NULL;
 
        atomic_set(&ctx->ref, 1);
-       init_waitqueue_head(&ctx->wait);
+       init_completion(&ctx->comp);
        ctx->file = file;
        INIT_LIST_HEAD(&ctx->events);
 
@@ -186,9 +189,9 @@ static struct ib_ucm_context *ib_ucm_ctx_alloc(struct ib_ucm_file *file)
                if (!result)
                        goto error;
 
-               down(&ctx_id_mutex);
+               mutex_lock(&ctx_id_mutex);
                result = idr_get_new(&ctx_id_table, ctx, &ctx->id);
-               up(&ctx_id_mutex);
+               mutex_unlock(&ctx_id_mutex);
        } while (result == -EAGAIN);
 
        if (result)
@@ -550,9 +553,9 @@ static ssize_t ib_ucm_create_id(struct ib_ucm_file *file,
 err2:
        ib_destroy_cm_id(ctx->cm_id);
 err1:
-       down(&ctx_id_mutex);
+       mutex_lock(&ctx_id_mutex);
        idr_remove(&ctx_id_table, ctx->id);
-       up(&ctx_id_mutex);
+       mutex_unlock(&ctx_id_mutex);
        kfree(ctx);
        return result;
 }
@@ -572,7 +575,7 @@ static ssize_t ib_ucm_destroy_id(struct ib_ucm_file *file,
        if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
                return -EFAULT;
 
-       down(&ctx_id_mutex);
+       mutex_lock(&ctx_id_mutex);
        ctx = idr_find(&ctx_id_table, cmd.id);
        if (!ctx)
                ctx = ERR_PTR(-ENOENT);
@@ -580,13 +583,13 @@ static ssize_t ib_ucm_destroy_id(struct ib_ucm_file *file,
                ctx = ERR_PTR(-EINVAL);
        else
                idr_remove(&ctx_id_table, ctx->id);
-       up(&ctx_id_mutex);
+       mutex_unlock(&ctx_id_mutex);
 
        if (IS_ERR(ctx))
                return PTR_ERR(ctx);
 
-       atomic_dec(&ctx->ref);
-       wait_event(ctx->wait, !atomic_read(&ctx->ref));
+       ib_ucm_ctx_put(ctx);
+       wait_for_completion(&ctx->comp);
 
        /* No new events will be generated after destroying the cm_id. */
        ib_destroy_cm_id(ctx->cm_id);
@@ -1280,9 +1283,9 @@ static int ib_ucm_close(struct inode *inode, struct file *filp)
                                 struct ib_ucm_context, file_list);
                up(&file->mutex);
 
-               down(&ctx_id_mutex);
+               mutex_lock(&ctx_id_mutex);
                idr_remove(&ctx_id_table, ctx->id);
-               up(&ctx_id_mutex);
+               mutex_unlock(&ctx_id_mutex);
 
                ib_destroy_cm_id(ctx->cm_id);
                ib_ucm_cleanup_events(ctx);
@@ -1318,15 +1321,6 @@ static struct class ucm_class = {
        .release = ib_ucm_release_class_dev
 };
 
-static ssize_t show_dev(struct class_device *class_dev, char *buf)
-{
-       struct ib_ucm_device *dev;
-       
-       dev = container_of(class_dev, struct ib_ucm_device, class_dev);
-       return print_dev_t(buf, dev->dev.dev);
-}
-static CLASS_DEVICE_ATTR(dev, S_IRUGO, show_dev, NULL);
-
 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
 {
        struct ib_ucm_device *dev;
@@ -1363,14 +1357,12 @@ static void ib_ucm_add_one(struct ib_device *device)
 
        ucm_dev->class_dev.class = &ucm_class;
        ucm_dev->class_dev.dev = device->dma_device;
+       ucm_dev->class_dev.devt = ucm_dev->dev.dev;
        snprintf(ucm_dev->class_dev.class_id, BUS_ID_SIZE, "ucm%d",
                 ucm_dev->devnum);
        if (class_device_register(&ucm_dev->class_dev))
                goto err_cdev;
 
-       if (class_device_create_file(&ucm_dev->class_dev,
-                                    &class_device_attr_dev))
-               goto err_class;
        if (class_device_create_file(&ucm_dev->class_dev,
                                     &class_device_attr_ibdev))
                goto err_class;