@@ -2520,10 +2520,21 @@ static ssize_t file_store(struct device *dev, struct device_attribute *attr,
return fsg_store_file(curlun, filesem, buf, count);
}
+static ssize_t forced_eject_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct fsg_lun *curlun = fsg_lun_from_dev(dev);
+ struct rw_semaphore *filesem = dev_get_drvdata(dev);
+
+ return fsg_store_forced_eject(curlun, filesem, buf, count);
+}
+
static DEVICE_ATTR_RW(nofua);
/* mode wil be set in fsg_lun_attr_is_visible() */
static DEVICE_ATTR(ro, 0, ro_show, ro_store);
static DEVICE_ATTR(file, 0, file_show, file_store);
+static DEVICE_ATTR_WO(forced_eject);
/****************************** FSG COMMON ******************************/
@@ -2677,6 +2688,7 @@ static struct attribute *fsg_lun_dev_attrs[] = {
&dev_attr_ro.attr,
&dev_attr_file.attr,
&dev_attr_nofua.attr,
+ &dev_attr_forced_eject.attr,
NULL
};
@@ -3090,6 +3102,18 @@ static ssize_t fsg_lun_opts_inquiry_string_store(struct config_item *item,
CONFIGFS_ATTR(fsg_lun_opts_, inquiry_string);
+static ssize_t fsg_lun_opts_forced_eject_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct fsg_lun_opts *opts = to_fsg_lun_opts(item);
+ struct fsg_opts *fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
+
+ return fsg_store_forced_eject(opts->lun, &fsg_opts->common->filesem,
+ page, len);
+}
+
+CONFIGFS_ATTR_WO(fsg_lun_opts_, forced_eject);
+
static struct configfs_attribute *fsg_lun_attrs[] = {
&fsg_lun_opts_attr_file,
&fsg_lun_opts_attr_ro,
@@ -3097,6 +3121,7 @@ static struct configfs_attribute *fsg_lun_attrs[] = {
&fsg_lun_opts_attr_cdrom,
&fsg_lun_opts_attr_nofua,
&fsg_lun_opts_attr_inquiry_string,
+ &fsg_lun_opts_attr_forced_eject,
NULL,
};
@@ -519,4 +519,15 @@ ssize_t fsg_store_inquiry_string(struct fsg_lun *curlun, const char *buf,
}
EXPORT_SYMBOL_GPL(fsg_store_inquiry_string);
+ssize_t fsg_store_forced_eject(struct fsg_lun *curlun, struct rw_semaphore *filesem,
+ const char *buf, size_t count)
+{
+ int ret;
+
+ curlun->prevent_medium_removal = 0;
+ ret = fsg_store_file(curlun, filesem, "", 0);
+ return ret < 0 ? ret : count;
+}
+EXPORT_SYMBOL_GPL(fsg_store_forced_eject);
+
MODULE_LICENSE("GPL");
@@ -219,5 +219,7 @@ ssize_t fsg_store_removable(struct fsg_lun *curlun, const char *buf,
size_t count);
ssize_t fsg_store_inquiry_string(struct fsg_lun *curlun, const char *buf,
size_t count);
+ssize_t fsg_store_forced_eject(struct fsg_lun *curlun, struct rw_semaphore *filesem,
+ const char *buf, size_t count);
#endif /* USB_STORAGE_COMMON_H */
It allows to reset prevent_medium_removal flag and "eject" the image. The patch is a completely alternative implementation of the previously proposed [1], the idea of which was born after the mentioned discussion. Signed-off-by: Maxim Devaev <mdevaev@gmail.com> Link: https://lore.kernel.org/lkml/20220406092445.215288-1-mdevaev@gmail.com [1] --- drivers/usb/gadget/function/f_mass_storage.c | 25 ++++++++++++++++++++ drivers/usb/gadget/function/storage_common.c | 11 +++++++++ drivers/usb/gadget/function/storage_common.h | 2 ++ 3 files changed, 38 insertions(+)