Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/greybus/manifest.c b/drivers/greybus/manifest.c
new file mode 100644
index 0000000..dd70406
--- /dev/null
+++ b/drivers/greybus/manifest.c
@@ -0,0 +1,533 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Greybus manifest parsing
+ *
+ * Copyright 2014-2015 Google Inc.
+ * Copyright 2014-2015 Linaro Ltd.
+ */
+
+#include <linux/greybus.h>
+
+static const char *get_descriptor_type_string(u8 type)
+{
+ switch (type) {
+ case GREYBUS_TYPE_INVALID:
+ return "invalid";
+ case GREYBUS_TYPE_STRING:
+ return "string";
+ case GREYBUS_TYPE_INTERFACE:
+ return "interface";
+ case GREYBUS_TYPE_CPORT:
+ return "cport";
+ case GREYBUS_TYPE_BUNDLE:
+ return "bundle";
+ default:
+ WARN_ON(1);
+ return "unknown";
+ }
+}
+
+/*
+ * We scan the manifest once to identify where all the descriptors
+ * are. The result is a list of these manifest_desc structures. We
+ * then pick through them for what we're looking for (starting with
+ * the interface descriptor). As each is processed we remove it from
+ * the list. When we're done the list should (probably) be empty.
+ */
+struct manifest_desc {
+ struct list_head links;
+
+ size_t size;
+ void *data;
+ enum greybus_descriptor_type type;
+};
+
+static void release_manifest_descriptor(struct manifest_desc *descriptor)
+{
+ list_del(&descriptor->links);
+ kfree(descriptor);
+}
+
+static void release_manifest_descriptors(struct gb_interface *intf)
+{
+ struct manifest_desc *descriptor;
+ struct manifest_desc *next;
+
+ list_for_each_entry_safe(descriptor, next, &intf->manifest_descs, links)
+ release_manifest_descriptor(descriptor);
+}
+
+static void release_cport_descriptors(struct list_head *head, u8 bundle_id)
+{
+ struct manifest_desc *desc, *tmp;
+ struct greybus_descriptor_cport *desc_cport;
+
+ list_for_each_entry_safe(desc, tmp, head, links) {
+ desc_cport = desc->data;
+
+ if (desc->type != GREYBUS_TYPE_CPORT)
+ continue;
+
+ if (desc_cport->bundle == bundle_id)
+ release_manifest_descriptor(desc);
+ }
+}
+
+static struct manifest_desc *get_next_bundle_desc(struct gb_interface *intf)
+{
+ struct manifest_desc *descriptor;
+ struct manifest_desc *next;
+
+ list_for_each_entry_safe(descriptor, next, &intf->manifest_descs, links)
+ if (descriptor->type == GREYBUS_TYPE_BUNDLE)
+ return descriptor;
+
+ return NULL;
+}
+
+/*
+ * Validate the given descriptor. Its reported size must fit within
+ * the number of bytes remaining, and it must have a recognized
+ * type. Check that the reported size is at least as big as what
+ * we expect to see. (It could be bigger, perhaps for a new version
+ * of the format.)
+ *
+ * Returns the (non-zero) number of bytes consumed by the descriptor,
+ * or a negative errno.
+ */
+static int identify_descriptor(struct gb_interface *intf,
+ struct greybus_descriptor *desc, size_t size)
+{
+ struct greybus_descriptor_header *desc_header = &desc->header;
+ struct manifest_desc *descriptor;
+ size_t desc_size;
+ size_t expected_size;
+
+ if (size < sizeof(*desc_header)) {
+ dev_err(&intf->dev, "manifest too small (%zu < %zu)\n", size,
+ sizeof(*desc_header));
+ return -EINVAL; /* Must at least have header */
+ }
+
+ desc_size = le16_to_cpu(desc_header->size);
+ if (desc_size > size) {
+ dev_err(&intf->dev, "descriptor too big (%zu > %zu)\n",
+ desc_size, size);
+ return -EINVAL;
+ }
+
+ /* Descriptor needs to at least have a header */
+ expected_size = sizeof(*desc_header);
+
+ switch (desc_header->type) {
+ case GREYBUS_TYPE_STRING:
+ expected_size += sizeof(struct greybus_descriptor_string);
+ expected_size += desc->string.length;
+
+ /* String descriptors are padded to 4 byte boundaries */
+ expected_size = ALIGN(expected_size, 4);
+ break;
+ case GREYBUS_TYPE_INTERFACE:
+ expected_size += sizeof(struct greybus_descriptor_interface);
+ break;
+ case GREYBUS_TYPE_BUNDLE:
+ expected_size += sizeof(struct greybus_descriptor_bundle);
+ break;
+ case GREYBUS_TYPE_CPORT:
+ expected_size += sizeof(struct greybus_descriptor_cport);
+ break;
+ case GREYBUS_TYPE_INVALID:
+ default:
+ dev_err(&intf->dev, "invalid descriptor type (%u)\n",
+ desc_header->type);
+ return -EINVAL;
+ }
+
+ if (desc_size < expected_size) {
+ dev_err(&intf->dev, "%s descriptor too small (%zu < %zu)\n",
+ get_descriptor_type_string(desc_header->type),
+ desc_size, expected_size);
+ return -EINVAL;
+ }
+
+ /* Descriptor bigger than what we expect */
+ if (desc_size > expected_size) {
+ dev_warn(&intf->dev, "%s descriptor size mismatch (want %zu got %zu)\n",
+ get_descriptor_type_string(desc_header->type),
+ expected_size, desc_size);
+ }
+
+ descriptor = kzalloc(sizeof(*descriptor), GFP_KERNEL);
+ if (!descriptor)
+ return -ENOMEM;
+
+ descriptor->size = desc_size;
+ descriptor->data = (char *)desc + sizeof(*desc_header);
+ descriptor->type = desc_header->type;
+ list_add_tail(&descriptor->links, &intf->manifest_descs);
+
+ /* desc_size is positive and is known to fit in a signed int */
+
+ return desc_size;
+}
+
+/*
+ * Find the string descriptor having the given id, validate it, and
+ * allocate a duplicate copy of it. The duplicate has an extra byte
+ * which guarantees the returned string is NUL-terminated.
+ *
+ * String index 0 is valid (it represents "no string"), and for
+ * that a null pointer is returned.
+ *
+ * Otherwise returns a pointer to a newly-allocated copy of the
+ * descriptor string, or an error-coded pointer on failure.
+ */
+static char *gb_string_get(struct gb_interface *intf, u8 string_id)
+{
+ struct greybus_descriptor_string *desc_string;
+ struct manifest_desc *descriptor;
+ bool found = false;
+ char *string;
+
+ /* A zero string id means no string (but no error) */
+ if (!string_id)
+ return NULL;
+
+ list_for_each_entry(descriptor, &intf->manifest_descs, links) {
+ if (descriptor->type != GREYBUS_TYPE_STRING)
+ continue;
+
+ desc_string = descriptor->data;
+ if (desc_string->id == string_id) {
+ found = true;
+ break;
+ }
+ }
+ if (!found)
+ return ERR_PTR(-ENOENT);
+
+ /* Allocate an extra byte so we can guarantee it's NUL-terminated */
+ string = kmemdup(&desc_string->string, desc_string->length + 1,
+ GFP_KERNEL);
+ if (!string)
+ return ERR_PTR(-ENOMEM);
+ string[desc_string->length] = '\0';
+
+ /* Ok we've used this string, so we're done with it */
+ release_manifest_descriptor(descriptor);
+
+ return string;
+}
+
+/*
+ * Find cport descriptors in the manifest associated with the given
+ * bundle, and set up data structures for the functions that use
+ * them. Returns the number of cports set up for the bundle, or 0
+ * if there is an error.
+ */
+static u32 gb_manifest_parse_cports(struct gb_bundle *bundle)
+{
+ struct gb_interface *intf = bundle->intf;
+ struct greybus_descriptor_cport *desc_cport;
+ struct manifest_desc *desc, *next, *tmp;
+ LIST_HEAD(list);
+ u8 bundle_id = bundle->id;
+ u16 cport_id;
+ u32 count = 0;
+ int i;
+
+ /* Set up all cport descriptors associated with this bundle */
+ list_for_each_entry_safe(desc, next, &intf->manifest_descs, links) {
+ if (desc->type != GREYBUS_TYPE_CPORT)
+ continue;
+
+ desc_cport = desc->data;
+ if (desc_cport->bundle != bundle_id)
+ continue;
+
+ cport_id = le16_to_cpu(desc_cport->id);
+ if (cport_id > CPORT_ID_MAX)
+ goto exit;
+
+ /* Nothing else should have its cport_id as control cport id */
+ if (cport_id == GB_CONTROL_CPORT_ID) {
+ dev_err(&bundle->dev, "invalid cport id found (%02u)\n",
+ cport_id);
+ goto exit;
+ }
+
+ /*
+ * Found one, move it to our temporary list after checking for
+ * duplicates.
+ */
+ list_for_each_entry(tmp, &list, links) {
+ desc_cport = tmp->data;
+ if (cport_id == le16_to_cpu(desc_cport->id)) {
+ dev_err(&bundle->dev,
+ "duplicate CPort %u found\n", cport_id);
+ goto exit;
+ }
+ }
+ list_move_tail(&desc->links, &list);
+ count++;
+ }
+
+ if (!count)
+ return 0;
+
+ bundle->cport_desc = kcalloc(count, sizeof(*bundle->cport_desc),
+ GFP_KERNEL);
+ if (!bundle->cport_desc)
+ goto exit;
+
+ bundle->num_cports = count;
+
+ i = 0;
+ list_for_each_entry_safe(desc, next, &list, links) {
+ desc_cport = desc->data;
+ memcpy(&bundle->cport_desc[i++], desc_cport,
+ sizeof(*desc_cport));
+
+ /* Release the cport descriptor */
+ release_manifest_descriptor(desc);
+ }
+
+ return count;
+exit:
+ release_cport_descriptors(&list, bundle_id);
+ /*
+ * Free all cports for this bundle to avoid 'excess descriptors'
+ * warnings.
+ */
+ release_cport_descriptors(&intf->manifest_descs, bundle_id);
+
+ return 0; /* Error; count should also be 0 */
+}
+
+/*
+ * Find bundle descriptors in the manifest and set up their data
+ * structures. Returns the number of bundles set up for the
+ * given interface.
+ */
+static u32 gb_manifest_parse_bundles(struct gb_interface *intf)
+{
+ struct manifest_desc *desc;
+ struct gb_bundle *bundle;
+ struct gb_bundle *bundle_next;
+ u32 count = 0;
+ u8 bundle_id;
+ u8 class;
+
+ while ((desc = get_next_bundle_desc(intf))) {
+ struct greybus_descriptor_bundle *desc_bundle;
+
+ /* Found one. Set up its bundle structure*/
+ desc_bundle = desc->data;
+ bundle_id = desc_bundle->id;
+ class = desc_bundle->class;
+
+ /* Done with this bundle descriptor */
+ release_manifest_descriptor(desc);
+
+ /* Ignore any legacy control bundles */
+ if (bundle_id == GB_CONTROL_BUNDLE_ID) {
+ dev_dbg(&intf->dev, "%s - ignoring control bundle\n",
+ __func__);
+ release_cport_descriptors(&intf->manifest_descs,
+ bundle_id);
+ continue;
+ }
+
+ /* Nothing else should have its class set to control class */
+ if (class == GREYBUS_CLASS_CONTROL) {
+ dev_err(&intf->dev,
+ "bundle %u cannot use control class\n",
+ bundle_id);
+ goto cleanup;
+ }
+
+ bundle = gb_bundle_create(intf, bundle_id, class);
+ if (!bundle)
+ goto cleanup;
+
+ /*
+ * Now go set up this bundle's functions and cports.
+ *
+ * A 'bundle' represents a device in greybus. It may require
+ * multiple cports for its functioning. If we fail to setup any
+ * cport of a bundle, we better reject the complete bundle as
+ * the device may not be able to function properly then.
+ *
+ * But, failing to setup a cport of bundle X doesn't mean that
+ * the device corresponding to bundle Y will not work properly.
+ * Bundles should be treated as separate independent devices.
+ *
+ * While parsing manifest for an interface, treat bundles as
+ * separate entities and don't reject entire interface and its
+ * bundles on failing to initialize a cport. But make sure the
+ * bundle which needs the cport, gets destroyed properly.
+ */
+ if (!gb_manifest_parse_cports(bundle)) {
+ gb_bundle_destroy(bundle);
+ continue;
+ }
+
+ count++;
+ }
+
+ return count;
+cleanup:
+ /* An error occurred; undo any changes we've made */
+ list_for_each_entry_safe(bundle, bundle_next, &intf->bundles, links) {
+ gb_bundle_destroy(bundle);
+ count--;
+ }
+ return 0; /* Error; count should also be 0 */
+}
+
+static bool gb_manifest_parse_interface(struct gb_interface *intf,
+ struct manifest_desc *interface_desc)
+{
+ struct greybus_descriptor_interface *desc_intf = interface_desc->data;
+ struct gb_control *control = intf->control;
+ char *str;
+
+ /* Handle the strings first--they can fail */
+ str = gb_string_get(intf, desc_intf->vendor_stringid);
+ if (IS_ERR(str))
+ return false;
+ control->vendor_string = str;
+
+ str = gb_string_get(intf, desc_intf->product_stringid);
+ if (IS_ERR(str))
+ goto out_free_vendor_string;
+ control->product_string = str;
+
+ /* Assign feature flags communicated via manifest */
+ intf->features = desc_intf->features;
+
+ /* Release the interface descriptor, now that we're done with it */
+ release_manifest_descriptor(interface_desc);
+
+ /* An interface must have at least one bundle descriptor */
+ if (!gb_manifest_parse_bundles(intf)) {
+ dev_err(&intf->dev, "manifest bundle descriptors not valid\n");
+ goto out_err;
+ }
+
+ return true;
+out_err:
+ kfree(control->product_string);
+ control->product_string = NULL;
+out_free_vendor_string:
+ kfree(control->vendor_string);
+ control->vendor_string = NULL;
+
+ return false;
+}
+
+/*
+ * Parse a buffer containing an interface manifest.
+ *
+ * If we find anything wrong with the content/format of the buffer
+ * we reject it.
+ *
+ * The first requirement is that the manifest's version is
+ * one we can parse.
+ *
+ * We make an initial pass through the buffer and identify all of
+ * the descriptors it contains, keeping track for each its type
+ * and the location size of its data in the buffer.
+ *
+ * Next we scan the descriptors, looking for an interface descriptor;
+ * there must be exactly one of those. When found, we record the
+ * information it contains, and then remove that descriptor (and any
+ * string descriptors it refers to) from further consideration.
+ *
+ * After that we look for the interface's bundles--there must be at
+ * least one of those.
+ *
+ * Returns true if parsing was successful, false otherwise.
+ */
+bool gb_manifest_parse(struct gb_interface *intf, void *data, size_t size)
+{
+ struct greybus_manifest *manifest;
+ struct greybus_manifest_header *header;
+ struct greybus_descriptor *desc;
+ struct manifest_desc *descriptor;
+ struct manifest_desc *interface_desc = NULL;
+ u16 manifest_size;
+ u32 found = 0;
+ bool result;
+
+ /* Manifest descriptor list should be empty here */
+ if (WARN_ON(!list_empty(&intf->manifest_descs)))
+ return false;
+
+ /* we have to have at _least_ the manifest header */
+ if (size < sizeof(*header)) {
+ dev_err(&intf->dev, "short manifest (%zu < %zu)\n",
+ size, sizeof(*header));
+ return false;
+ }
+
+ /* Make sure the size is right */
+ manifest = data;
+ header = &manifest->header;
+ manifest_size = le16_to_cpu(header->size);
+ if (manifest_size != size) {
+ dev_err(&intf->dev, "manifest size mismatch (%zu != %u)\n",
+ size, manifest_size);
+ return false;
+ }
+
+ /* Validate major/minor number */
+ if (header->version_major > GREYBUS_VERSION_MAJOR) {
+ dev_err(&intf->dev, "manifest version too new (%u.%u > %u.%u)\n",
+ header->version_major, header->version_minor,
+ GREYBUS_VERSION_MAJOR, GREYBUS_VERSION_MINOR);
+ return false;
+ }
+
+ /* OK, find all the descriptors */
+ desc = manifest->descriptors;
+ size -= sizeof(*header);
+ while (size) {
+ int desc_size;
+
+ desc_size = identify_descriptor(intf, desc, size);
+ if (desc_size < 0) {
+ result = false;
+ goto out;
+ }
+ desc = (struct greybus_descriptor *)((char *)desc + desc_size);
+ size -= desc_size;
+ }
+
+ /* There must be a single interface descriptor */
+ list_for_each_entry(descriptor, &intf->manifest_descs, links) {
+ if (descriptor->type == GREYBUS_TYPE_INTERFACE)
+ if (!found++)
+ interface_desc = descriptor;
+ }
+ if (found != 1) {
+ dev_err(&intf->dev, "manifest must have 1 interface descriptor (%u found)\n",
+ found);
+ result = false;
+ goto out;
+ }
+
+ /* Parse the manifest, starting with the interface descriptor */
+ result = gb_manifest_parse_interface(intf, interface_desc);
+
+ /*
+ * We really should have no remaining descriptors, but we
+ * don't know what newer format manifests might leave.
+ */
+ if (result && !list_empty(&intf->manifest_descs))
+ dev_info(&intf->dev, "excess descriptors in interface manifest\n");
+out:
+ release_manifest_descriptors(intf);
+
+ return result;
+}