Re: [Qemu-devel] [PATCH v4 3/5] usb-mtp: Support delete of mtp objects
On Tue, Feb 20, 2018 at 05:59:02PM -0500, Bandan Das wrote:
> Write of existing objects by the initiator is acheived by
> making a temporary buffer with the new changes, deleting the
> old file and then writing a new file with the same name.
>
> Also, add a "readonly" property which needs to be set to false
> for deletion to work.
>
> Signed-off-by: Bandan Das
> ---
> hw/usb/dev-mtp.c | 123
> +++
> 1 file changed, 123 insertions(+)
>
> diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c
> index 63f8f3b90b..5ef77f3e9f 100644
> --- a/hw/usb/dev-mtp.c
> +++ b/hw/usb/dev-mtp.c
> @@ -46,6 +46,7 @@ enum mtp_code {
> CMD_GET_OBJECT_HANDLES = 0x1007,
> CMD_GET_OBJECT_INFO= 0x1008,
> CMD_GET_OBJECT = 0x1009,
> +CMD_DELETE_OBJECT = 0x100b,
> CMD_GET_PARTIAL_OBJECT = 0x101b,
> CMD_GET_OBJECT_PROPS_SUPPORTED = 0x9801,
> CMD_GET_OBJECT_PROP_DESC = 0x9802,
> @@ -62,6 +63,8 @@ enum mtp_code {
> RES_INVALID_STORAGE_ID = 0x2008,
> RES_INVALID_OBJECT_HANDLE = 0x2009,
> RES_INVALID_OBJECT_FORMAT_CODE = 0x200b,
> +RES_STORE_READ_ONLY= 0x200e,
> +RES_PARTIAL_DELETE = 0x2012,
> RES_SPEC_BY_FORMAT_UNSUPPORTED = 0x2014,
> RES_INVALID_PARENT_OBJECT = 0x201a,
> RES_INVALID_PARAMETER = 0x201d,
> @@ -172,6 +175,7 @@ struct MTPState {
> MTPControl *result;
> uint32_t session;
> uint32_t next_handle;
> +bool readonly;
>
> QTAILQ_HEAD(, MTPObject) objects;
> #ifdef CONFIG_INOTIFY1
> @@ -799,6 +803,7 @@ static MTPData *usb_mtp_get_device_info(MTPState *s,
> MTPControl *c)
> CMD_GET_NUM_OBJECTS,
> CMD_GET_OBJECT_HANDLES,
> CMD_GET_OBJECT_INFO,
> +CMD_DELETE_OBJECT,
Should we not advertize this in the first place if the device is readonly.
> CMD_GET_OBJECT,
> CMD_GET_PARTIAL_OBJECT,
> CMD_GET_OBJECT_PROPS_SUPPORTED,
> @@ -1113,6 +1118,116 @@ static MTPData
> *usb_mtp_get_object_prop_value(MTPState *s, MTPControl *c,
> return d;
> }
>
> +/* Return correct return code for a delete event */
> +enum {
> +ALL_DELETE,
> +PARTIAL_DELETE,
> +READ_ONLY,
> +};
> +
> +/* Assumes that children, if any, have been already freed */
> +static void usb_mtp_object_free_one(MTPState *s, MTPObject *o)
> +{
> +#ifndef CONFIG_INOTIFY1
> +assert(o->nchildren == 0);
> +QTAILQ_REMOVE(&s->objects, o, next);
> +g_free(o->name);
> +g_free(o->path);
> +g_free(o);
> +#endif
> +}
> +
> +static int usb_mtp_deletefn(MTPState *s, MTPObject *o, uint32_t trans)
> +{
> +MTPObject *iter, *iter2;
> +bool partial_delete = false;
> +bool success = false;
> +
> +/*
> + * TODO: Add support for Protection Status
> + */
> +
> +QLIST_FOREACH(iter, &o->children, list) {
> +if (iter->format == FMT_ASSOCIATION) {
> +QLIST_FOREACH(iter2, &iter->children, list) {
> +usb_mtp_deletefn(s, iter2, trans);
> +}
> +}
> +}
> +
> +if (o->format == FMT_UNDEFINED_OBJECT) {
> +if (remove(o->path)) {
> +partial_delete = true;
> +} else {
> +usb_mtp_object_free_one(s, o);
> +success = true;
> +}
> +}
> +
> +if (o->format == FMT_ASSOCIATION) {
> +if (rmdir(o->path)) {
> +partial_delete = true;
> +} else {
> +usb_mtp_object_free_one(s, o);
> +success = true;
> +}
> +}
> +
> +if (success && partial_delete) {
> +return PARTIAL_DELETE;
> +}
> +if (!success && partial_delete) {
> +return READ_ONLY;
> +}
> +return ALL_DELETE;
> +}
> +
> +static void usb_mtp_object_delete(MTPState *s, uint32_t handle,
> + uint32_t format_code, uint32_t trans)
> +{
> +MTPObject *o;
> +int ret;
> +
> +/* Return error if store is read-only */
> +if (!FLAG_SET(s, MTP_FLAG_WRITABLE)) {
> +usb_mtp_queue_result(s, RES_STORE_READ_ONLY,
> + trans, 0, 0, 0, 0);
> +return;
> +}
> +
> +if (format_code != 0) {
> +usb_mtp_queue_result(s, RES_SPEC_BY_FORMAT_UNSUPPORTED,
> + trans, 0, 0, 0, 0);
> +return;
> +}
> +
> +if (handle == 0xFFF) {
> +o = QTAILQ_FIRST(&s->objects);
> +} else {
> +o = usb_mtp_object_lookup(s, handle);
> +}
> +if (o == NULL) {
> +usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
> + trans, 0, 0, 0, 0);
> +return;
> +}
> +
> +ret = usb_mtp_deletefn(s, o, trans);
> +if (ret == PARTIAL_DELETE) {
> +usb_mtp_queue_result(s, RES_PARTIAL_DELETE,
> + trans, 0, 0, 0, 0);
> +return;
> +} else if (ret == RE
[Qemu-devel] [PATCH v4 3/5] usb-mtp: Support delete of mtp objects
Write of existing objects by the initiator is acheived by
making a temporary buffer with the new changes, deleting the
old file and then writing a new file with the same name.
Also, add a "readonly" property which needs to be set to false
for deletion to work.
Signed-off-by: Bandan Das
---
hw/usb/dev-mtp.c | 123 +++
1 file changed, 123 insertions(+)
diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c
index 63f8f3b90b..5ef77f3e9f 100644
--- a/hw/usb/dev-mtp.c
+++ b/hw/usb/dev-mtp.c
@@ -46,6 +46,7 @@ enum mtp_code {
CMD_GET_OBJECT_HANDLES = 0x1007,
CMD_GET_OBJECT_INFO= 0x1008,
CMD_GET_OBJECT = 0x1009,
+CMD_DELETE_OBJECT = 0x100b,
CMD_GET_PARTIAL_OBJECT = 0x101b,
CMD_GET_OBJECT_PROPS_SUPPORTED = 0x9801,
CMD_GET_OBJECT_PROP_DESC = 0x9802,
@@ -62,6 +63,8 @@ enum mtp_code {
RES_INVALID_STORAGE_ID = 0x2008,
RES_INVALID_OBJECT_HANDLE = 0x2009,
RES_INVALID_OBJECT_FORMAT_CODE = 0x200b,
+RES_STORE_READ_ONLY= 0x200e,
+RES_PARTIAL_DELETE = 0x2012,
RES_SPEC_BY_FORMAT_UNSUPPORTED = 0x2014,
RES_INVALID_PARENT_OBJECT = 0x201a,
RES_INVALID_PARAMETER = 0x201d,
@@ -172,6 +175,7 @@ struct MTPState {
MTPControl *result;
uint32_t session;
uint32_t next_handle;
+bool readonly;
QTAILQ_HEAD(, MTPObject) objects;
#ifdef CONFIG_INOTIFY1
@@ -799,6 +803,7 @@ static MTPData *usb_mtp_get_device_info(MTPState *s,
MTPControl *c)
CMD_GET_NUM_OBJECTS,
CMD_GET_OBJECT_HANDLES,
CMD_GET_OBJECT_INFO,
+CMD_DELETE_OBJECT,
CMD_GET_OBJECT,
CMD_GET_PARTIAL_OBJECT,
CMD_GET_OBJECT_PROPS_SUPPORTED,
@@ -1113,6 +1118,116 @@ static MTPData *usb_mtp_get_object_prop_value(MTPState
*s, MTPControl *c,
return d;
}
+/* Return correct return code for a delete event */
+enum {
+ALL_DELETE,
+PARTIAL_DELETE,
+READ_ONLY,
+};
+
+/* Assumes that children, if any, have been already freed */
+static void usb_mtp_object_free_one(MTPState *s, MTPObject *o)
+{
+#ifndef CONFIG_INOTIFY1
+assert(o->nchildren == 0);
+QTAILQ_REMOVE(&s->objects, o, next);
+g_free(o->name);
+g_free(o->path);
+g_free(o);
+#endif
+}
+
+static int usb_mtp_deletefn(MTPState *s, MTPObject *o, uint32_t trans)
+{
+MTPObject *iter, *iter2;
+bool partial_delete = false;
+bool success = false;
+
+/*
+ * TODO: Add support for Protection Status
+ */
+
+QLIST_FOREACH(iter, &o->children, list) {
+if (iter->format == FMT_ASSOCIATION) {
+QLIST_FOREACH(iter2, &iter->children, list) {
+usb_mtp_deletefn(s, iter2, trans);
+}
+}
+}
+
+if (o->format == FMT_UNDEFINED_OBJECT) {
+if (remove(o->path)) {
+partial_delete = true;
+} else {
+usb_mtp_object_free_one(s, o);
+success = true;
+}
+}
+
+if (o->format == FMT_ASSOCIATION) {
+if (rmdir(o->path)) {
+partial_delete = true;
+} else {
+usb_mtp_object_free_one(s, o);
+success = true;
+}
+}
+
+if (success && partial_delete) {
+return PARTIAL_DELETE;
+}
+if (!success && partial_delete) {
+return READ_ONLY;
+}
+return ALL_DELETE;
+}
+
+static void usb_mtp_object_delete(MTPState *s, uint32_t handle,
+ uint32_t format_code, uint32_t trans)
+{
+MTPObject *o;
+int ret;
+
+/* Return error if store is read-only */
+if (!FLAG_SET(s, MTP_FLAG_WRITABLE)) {
+usb_mtp_queue_result(s, RES_STORE_READ_ONLY,
+ trans, 0, 0, 0, 0);
+return;
+}
+
+if (format_code != 0) {
+usb_mtp_queue_result(s, RES_SPEC_BY_FORMAT_UNSUPPORTED,
+ trans, 0, 0, 0, 0);
+return;
+}
+
+if (handle == 0xFFF) {
+o = QTAILQ_FIRST(&s->objects);
+} else {
+o = usb_mtp_object_lookup(s, handle);
+}
+if (o == NULL) {
+usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
+ trans, 0, 0, 0, 0);
+return;
+}
+
+ret = usb_mtp_deletefn(s, o, trans);
+if (ret == PARTIAL_DELETE) {
+usb_mtp_queue_result(s, RES_PARTIAL_DELETE,
+ trans, 0, 0, 0, 0);
+return;
+} else if (ret == READ_ONLY) {
+usb_mtp_queue_result(s, RES_STORE_READ_ONLY, trans,
+ 0, 0, 0, 0);
+return;
+} else {
+usb_mtp_queue_result(s, RES_OK, trans,
+ 0, 0, 0, 0);
+return;
+}
+}
+
static void usb_mtp_command(MTPState *s, MTPControl *c)
{
MTPData *data_in = NULL;
@@ -1239,6 +1354,9 @@ static void usb_mtp_command(MTPState *s, MTPControl *c)
ret
