uml: send pointers instead of structures to I/O thread

[platform/adaptation/renesas_rcar/renesas_kernel.git] / arch / um / drivers / ubd_kern.c

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 5ef47b7..9200a45 100644 (file)
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -503,7 +503,7 @@ static LIST_HEAD(restart);
 /* Called without dev->lock held, and only in interrupt context. */
 static void ubd_handler(void)
 {
-       struct io_thread_req req;
+       struct io_thread_req *req;
        struct request *rq;
        struct ubd *ubd;
        struct list_head *list, *next_ele;
@@ -511,7 +511,8 @@ static void ubd_handler(void)
        int n;
 
        while(1){
-               n = os_read_file_k(thread_fd, &req, sizeof(req));
+               n = os_read_file_k(thread_fd, &req,
+                                  sizeof(struct io_thread_req *));
                if(n != sizeof(req)){
                        if(n == -EAGAIN)
                                break;
@@ -520,10 +521,11 @@ static void ubd_handler(void)
                        return;
                }
 
-               rq = req.req;
-               rq->nr_sectors -= req.length >> 9;
+               rq = req->req;
+               rq->nr_sectors -= req->length >> 9;
                if(rq->nr_sectors == 0)
                        ubd_finish(rq, rq->hard_nr_sectors << 9);
+               kfree(req);
        }
        reactivate_fd(thread_fd, UBD_IRQ);
 
@@ -1078,7 +1080,7 @@ static void prepare_request(struct request *req, struct io_thread_req *io_req,
 /* Called with dev->lock held */
 static void do_ubd_request(request_queue_t *q)
 {
-       struct io_thread_req io_req;
+       struct io_thread_req *io_req;
        struct request *req;
        int n;
 
@@ -1099,13 +1101,20 @@ static void do_ubd_request(request_queue_t *q)
                while(dev->start_sg < dev->end_sg){
                        struct scatterlist *sg = &dev->sg[dev->start_sg];
 
-                       prepare_request(req, &io_req,
+                       io_req = kmalloc(sizeof(struct io_thread_req),
+                                        GFP_KERNEL | GFP_ATOMIC);
+                       if(io_req == NULL){
+                               if(list_empty(&dev->restart))
+                                       list_add(&dev->restart, &restart);
+                               return;
+                       }
+                       prepare_request(req, io_req,
                                        (unsigned long long) req->sector << 9,
                                        sg->offset, sg->length, sg->page);
 
-                       n = os_write_file_k(thread_fd, (char *) &io_req,
-                                           sizeof(io_req));
-                       if(n != sizeof(io_req)){
+                       n = os_write_file_k(thread_fd, &io_req,
+                                           sizeof(struct io_thread_req *));
+                       if(n != sizeof(struct io_thread_req *)){
                                if(n != -EAGAIN)
                                        printk("write to io thread failed, "
                                               "errno = %d\n", -n);
@@ -1437,13 +1446,14 @@ static int io_count = 0;
 
 int io_thread(void *arg)
 {
-       struct io_thread_req req;
+       struct io_thread_req *req;
        int n;
 
        ignore_sigwinch_sig();
        while(1){
-               n = os_read_file_k(kernel_fd, &req, sizeof(req));
-               if(n != sizeof(req)){
+               n = os_read_file_k(kernel_fd, &req,
+                                sizeof(struct io_thread_req *));
+               if(n != sizeof(struct io_thread_req *)){
                        if(n < 0)
                                printk("io_thread - read failed, fd = %d, "
                                       "err = %d\n", kernel_fd, -n);
@@ -1454,9 +1464,10 @@ int io_thread(void *arg)
                        continue;
                }
                io_count++;
-               do_io(&req);
-               n = os_write_file_k(kernel_fd, &req, sizeof(req));
-               if(n != sizeof(req))
+               do_io(req);
+               n = os_write_file_k(kernel_fd, &req,
+                                 sizeof(struct io_thread_req *));
+               if(n != sizeof(struct io_thread_req *))
                        printk("io_thread - write failed, fd = %d, err = %d\n",
                               kernel_fd, -n);
        }