usb: gadget: f_mass_storage: create fsg_common_set_num_buffers for use in fsg_common_init

fsg_common_init is a lengthy function. Factor a portion of it out.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index da87ffe..79d9899 100644 (file)
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -2681,6 +2681,49 @@ static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
        }
 }
 
+int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
+{
+       struct fsg_buffhd *bh, *buffhds;
+       int i, rc;
+
+       rc = fsg_num_buffers_validate(n);
+       if (rc != 0)
+               return rc;
+
+       buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
+       if (!buffhds)
+               return -ENOMEM;
+
+       /* Data buffers cyclic list */
+       bh = buffhds;
+       i = n;
+       goto buffhds_first_it;
+       do {
+               bh->next = bh + 1;
+               ++bh;
+buffhds_first_it:
+               bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
+               if (unlikely(!bh->buf))
+                       goto error_release;
+       } while (--i);
+       bh->next = buffhds;
+
+       _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
+       common->fsg_num_buffers = n;
+       common->buffhds = buffhds;
+
+       return 0;
+
+error_release:
+       /*
+        * "buf"s pointed to by heads after n - i are NULL
+        * so releasing them won't hurt
+        */
+       _fsg_common_free_buffers(buffhds, n);
+
+       return -ENOMEM;
+}
+
 static inline void fsg_common_remove_sysfs(struct fsg_lun *lun)
 {
        device_remove_file(&lun->dev, &dev_attr_nofua);
@@ -2714,17 +2757,12 @@ struct fsg_common *fsg_common_init(struct fsg_common *common,
                                   struct fsg_config *cfg)
 {
        struct usb_gadget *gadget = cdev->gadget;
-       struct fsg_buffhd *bh;
        struct fsg_lun **curlun_it;
        struct fsg_lun_config *lcfg;
        struct usb_string *us;
        int nluns, i, rc;
        char *pathbuf;
 
-       rc = fsg_num_buffers_validate(cfg->fsg_num_buffers);
-       if (rc != 0)
-               return ERR_PTR(rc);
-
        /* Find out how many LUNs there should be */
        nluns = cfg->nluns;
        if (nluns < 1 || nluns > FSG_MAX_LUNS) {
@@ -2738,15 +2776,12 @@ struct fsg_common *fsg_common_init(struct fsg_common *common,
        fsg_common_set_sysfs(common, true);
        common->state = FSG_STATE_IDLE;
 
-       common->fsg_num_buffers = cfg->fsg_num_buffers;
-       common->buffhds = kcalloc(common->fsg_num_buffers,
-                                 sizeof *(common->buffhds), GFP_KERNEL);
-       if (!common->buffhds) {
+       rc = fsg_common_set_num_buffers(common, cfg->fsg_num_buffers);
+       if (rc) {
                if (common->free_storage_on_release)
                        kfree(common);
-               return ERR_PTR(-ENOMEM);
+               return ERR_PTR(rc);
        }
-
        common->ops = cfg->ops;
        common->private_data = cfg->private_data;
 
@@ -2833,21 +2868,6 @@ struct fsg_common *fsg_common_init(struct fsg_common *common,
        }
        common->nluns = nluns;
 
-       /* Data buffers cyclic list */
-       bh = common->buffhds;
-       i = common->fsg_num_buffers;
-       goto buffhds_first_it;
-       do {
-               bh->next = bh + 1;
-               ++bh;
-buffhds_first_it:
-               bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
-               if (unlikely(!bh->buf)) {
-                       rc = -ENOMEM;
-                       goto error_release;
-               }
-       } while (--i);
-       bh->next = common->buffhds;
 
        /* Prepare inquiryString */
        i = get_default_bcdDevice();

diff --git a/drivers/usb/gadget/f_mass_storage.h b/drivers/usb/gadget/f_mass_storage.h
index 1b88eae..a00f51a 100644 (file)
--- a/drivers/usb/gadget/f_mass_storage.h
+++ b/drivers/usb/gadget/f_mass_storage.h
@@ -104,6 +104,8 @@ struct fsg_common *fsg_common_init(struct fsg_common *common,
 
 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs);
 
+int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n);
+
 void fsg_config_from_params(struct fsg_config *cfg,
                            const struct fsg_module_parameters *params,
                            unsigned int fsg_num_buffers);