X-Git-Url: https://git.kernelconcepts.de/?a=blobdiff_plain;f=drivers%2Fusb%2Fgadget%2Fstorage_common.c;h=ec20a1f50c2d702e56f6e6a79f03485607a36189;hb=b8798636798ee04feb0f1bb87eec0027e3f68d98;hp=8bd5f2d838db11f5fd6ffa0f14f02395185d6dc1;hpb=81a1d5ea6670acecf1366cd6a4d328c123bdf9fa;p=karo-tx-linux.git

diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
index 8bd5f2d838db..ec20a1f50c2d 100644
--- a/drivers/usb/gadget/storage_common.c
+++ b/drivers/usb/gadget/storage_common.c
@@ -371,6 +371,23 @@ ssize_t fsg_show_removable(struct fsg_lun *curlun, char *buf)
 }
 EXPORT_SYMBOL(fsg_show_removable);
 
+/*
+ * The caller must hold fsg->filesem for reading when calling this function.
+ */
+static ssize_t _fsg_store_ro(struct fsg_lun *curlun, bool ro)
+{
+	if (fsg_lun_is_open(curlun)) {
+		LDBG(curlun, "read-only status change prevented\n");
+		return -EBUSY;
+	}
+
+	curlun->ro = ro;
+	curlun->initially_ro = ro;
+	LDBG(curlun, "read-only status set to %d\n", curlun->ro);
+
+	return 0;
+}
+
 ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem,
 		     const char *buf, size_t count)
 {
@@ -386,16 +403,11 @@ ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem,
 	 * backing file is closed.
 	 */
 	down_read(filesem);
-	if (fsg_lun_is_open(curlun)) {
-		LDBG(curlun, "read-only status change prevented\n");
-		rc = -EBUSY;
-	} else {
-		curlun->ro = ro;
-		curlun->initially_ro = ro;
-		LDBG(curlun, "read-only status set to %d\n", curlun->ro);
+	rc = _fsg_store_ro(curlun, ro);
+	if (!rc)
 		rc = count;
-	}
 	up_read(filesem);
+
 	return rc;
 }
 EXPORT_SYMBOL(fsg_store_ro);
@@ -450,7 +462,8 @@ ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
 }
 EXPORT_SYMBOL(fsg_store_file);
 
-ssize_t fsg_store_cdrom(struct fsg_lun *curlun, const char *buf, size_t count)
+ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem,
+			const char *buf, size_t count)
 {
 	bool		cdrom;
 	int		ret;
@@ -459,9 +472,16 @@ ssize_t fsg_store_cdrom(struct fsg_lun *curlun, const char *buf, size_t count)
 	if (ret)
 		return ret;
 
-	curlun->cdrom = cdrom;
+	down_read(filesem);
+	ret = cdrom ? _fsg_store_ro(curlun, true) : 0;
 
-	return count;
+	if (!ret) {
+		curlun->cdrom = cdrom;
+		ret = count;
+	}
+	up_read(filesem);
+
+	return ret;
 }
 EXPORT_SYMBOL(fsg_store_cdrom);