Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 128 insertions, 43 deletions

diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c
index 0254ed39f..4ba42f1fa 100644
--- a/fs/cachefiles/ondemand.c
+++ b/fs/cachefiles/ondemand.c
@@ -9,21 +9,19 @@ static int cachefiles_ondemand_fd_release(struct inode *inode,
 {
 	struct cachefiles_object *object = file->private_data;
 	struct cachefiles_cache *cache = object->volume->cache;
-	int object_id = object->ondemand_id;
+	struct cachefiles_ondemand_info *info = object->ondemand;
+	int object_id = info->ondemand_id;
 	struct cachefiles_req *req;
 	XA_STATE(xas, &cache->reqs, 0);
 
 	xa_lock(&cache->reqs);
-	object->ondemand_id = CACHEFILES_ONDEMAND_ID_CLOSED;
+	info->ondemand_id = CACHEFILES_ONDEMAND_ID_CLOSED;
+	cachefiles_ondemand_set_object_close(object);
 
-	/*
-	 * Flush all pending READ requests since their completion depends on
-	 * anon_fd.
-	 */
-	xas_for_each(&xas, req, ULONG_MAX) {
+	/* Only flush CACHEFILES_REQ_NEW marked req to avoid race with daemon_read */
+	xas_for_each_marked(&xas, req, ULONG_MAX, CACHEFILES_REQ_NEW) {
 		if (req->msg.object_id == object_id &&
-		    req->msg.opcode == CACHEFILES_OP_READ) {
-			req->error = -EIO;
+		    req->msg.opcode == CACHEFILES_OP_CLOSE) {
 			complete(&req->done);
 			xas_store(&xas, NULL);
 		}
@@ -52,7 +50,7 @@ static ssize_t cachefiles_ondemand_fd_write_iter(struct kiocb *kiocb,
 		return -ENOBUFS;
 
 	cachefiles_begin_secure(cache, &saved_cred);
-	ret = __cachefiles_prepare_write(object, file, &pos, &len, true);
+	ret = __cachefiles_prepare_write(object, file, &pos, &len, len, true);
 	cachefiles_end_secure(cache, saved_cred);
 	if (ret < 0)
 		return ret;
@@ -176,11 +174,37 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args)
 		set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags);
 	trace_cachefiles_ondemand_copen(req->object, id, size);
 
+	cachefiles_ondemand_set_object_open(req->object);
+	wake_up_all(&cache->daemon_pollwq);
+
 out:
 	complete(&req->done);
 	return ret;
 }
 
+int cachefiles_ondemand_restore(struct cachefiles_cache *cache, char *args)
+{
+	struct cachefiles_req *req;
+
+	XA_STATE(xas, &cache->reqs, 0);
+
+	if (!test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags))
+		return -EOPNOTSUPP;
+
+	/*
+	 * Reset the requests to CACHEFILES_REQ_NEW state, so that the
+	 * requests have been processed halfway before the crash of the
+	 * user daemon could be reprocessed after the recovery.
+	 */
+	xas_lock(&xas);
+	xas_for_each(&xas, req, ULONG_MAX)
+		xas_set_mark(&xas, CACHEFILES_REQ_NEW);
+	xas_unlock(&xas);
+
+	wake_up_all(&cache->daemon_pollwq);
+	return 0;
+}
+
 static int cachefiles_ondemand_get_fd(struct cachefiles_req *req)
 {
 	struct cachefiles_object *object;
@@ -218,8 +242,7 @@ static int cachefiles_ondemand_get_fd(struct cachefiles_req *req)
 
 	load = (void *)req->msg.data;
 	load->fd = fd;
-	req->msg.object_id = object_id;
-	object->ondemand_id = object_id;
+	object->ondemand->ondemand_id = object_id;
 
 	cachefiles_get_unbind_pincount(cache);
 	trace_cachefiles_ondemand_open(object, &req->msg, load);
@@ -234,6 +257,43 @@ err:
 	return ret;
 }
 
+static void ondemand_object_worker(struct work_struct *work)
+{
+	struct cachefiles_ondemand_info *info =
+		container_of(work, struct cachefiles_ondemand_info, ondemand_work);
+
+	cachefiles_ondemand_init_object(info->object);
+}
+
+/*
+ * If there are any inflight or subsequent READ requests on the
+ * closed object, reopen it.
+ * Skip read requests whose related object is reopening.
+ */
+static struct cachefiles_req *cachefiles_ondemand_select_req(struct xa_state *xas,
+							      unsigned long xa_max)
+{
+	struct cachefiles_req *req;
+	struct cachefiles_object *object;
+	struct cachefiles_ondemand_info *info;
+
+	xas_for_each_marked(xas, req, xa_max, CACHEFILES_REQ_NEW) {
+		if (req->msg.opcode != CACHEFILES_OP_READ)
+			return req;
+		object = req->object;
+		info = object->ondemand;
+		if (cachefiles_ondemand_object_is_close(object)) {
+			cachefiles_ondemand_set_object_reopening(object);
+			queue_work(fscache_wq, &info->ondemand_work);
+			continue;
+		}
+		if (cachefiles_ondemand_object_is_reopening(object))
+			continue;
+		return req;
+	}
+	return NULL;
+}
+
 ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
 					char __user *_buffer, size_t buflen)
 {
@@ -244,16 +304,16 @@ ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
 	int ret = 0;
 	XA_STATE(xas, &cache->reqs, cache->req_id_next);
 
+	xa_lock(&cache->reqs);
 	/*
 	 * Cyclically search for a request that has not ever been processed,
 	 * to prevent requests from being processed repeatedly, and make
 	 * request distribution fair.
 	 */
-	xa_lock(&cache->reqs);
-	req = xas_find_marked(&xas, UINT_MAX, CACHEFILES_REQ_NEW);
+	req = cachefiles_ondemand_select_req(&xas, ULONG_MAX);
 	if (!req && cache->req_id_next > 0) {
 		xas_set(&xas, 0);
-		req = xas_find_marked(&xas, cache->req_id_next - 1, CACHEFILES_REQ_NEW);
+		req = cachefiles_ondemand_select_req(&xas, cache->req_id_next - 1);
 	}
 	if (!req) {
 		xa_unlock(&cache->reqs);
@@ -273,14 +333,18 @@ ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
 	xa_unlock(&cache->reqs);
 
 	id = xas.xa_index;
-	msg->msg_id = id;
 
 	if (msg->opcode == CACHEFILES_OP_OPEN) {
 		ret = cachefiles_ondemand_get_fd(req);
-		if (ret)
+		if (ret) {
+			cachefiles_ondemand_set_object_close(req->object);
 			goto error;
+		}
 	}
 
+	msg->msg_id = id;
+	msg->object_id = req->object->ondemand->ondemand_id;
+
 	if (copy_to_user(_buffer, msg, n) != 0) {
 		ret = -EFAULT;
 		goto err_put_fd;
@@ -313,19 +377,23 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object,
 					void *private)
 {
 	struct cachefiles_cache *cache = object->volume->cache;
-	struct cachefiles_req *req;
+	struct cachefiles_req *req = NULL;
 	XA_STATE(xas, &cache->reqs, 0);
 	int ret;
 
 	if (!test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags))
 		return 0;
 
-	if (test_bit(CACHEFILES_DEAD, &cache->flags))
-		return -EIO;
+	if (test_bit(CACHEFILES_DEAD, &cache->flags)) {
+		ret = -EIO;
+		goto out;
+	}
 
 	req = kzalloc(sizeof(*req) + data_len, GFP_KERNEL);
-	if (!req)
-		return -ENOMEM;
+	if (!req) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	req->object = object;
 	init_completion(&req->done);
@@ -363,8 +431,9 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object,
 		/* coupled with the barrier in cachefiles_flush_reqs() */
 		smp_mb();
 
-		if (opcode != CACHEFILES_OP_OPEN && object->ondemand_id <= 0) {
-			WARN_ON_ONCE(object->ondemand_id == 0);
+		if (opcode == CACHEFILES_OP_CLOSE &&
+			!cachefiles_ondemand_object_is_open(object)) {
+			WARN_ON_ONCE(object->ondemand->ondemand_id == 0);
 			xas_unlock(&xas);
 			ret = -EIO;
 			goto out;
@@ -387,7 +456,15 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object,
 	wake_up_all(&cache->daemon_pollwq);
 	wait_for_completion(&req->done);
 	ret = req->error;
+	kfree(req);
+	return ret;
 out:
+	/* Reset the object to close state in error handling path.
+	 * If error occurs after creating the anonymous fd,
+	 * cachefiles_ondemand_fd_release() will set object to close.
+	 */
+	if (opcode == CACHEFILES_OP_OPEN)
+		cachefiles_ondemand_set_object_close(object);
 	kfree(req);
 	return ret;
 }
@@ -430,18 +507,10 @@ static int cachefiles_ondemand_init_close_req(struct cachefiles_req *req,
 					      void *private)
 {
 	struct cachefiles_object *object = req->object;
-	int object_id = object->ondemand_id;
 
-	/*
-	 * It's possible that object id is still 0 if the cookie looking up
-	 * phase failed before OPEN request has ever been sent. Also avoid
-	 * sending CLOSE request for CACHEFILES_ONDEMAND_ID_CLOSED, which means
-	 * anon_fd has already been closed.
-	 */
-	if (object_id <= 0)
+	if (!cachefiles_ondemand_object_is_open(object))
 		return -ENOENT;
 
-	req->msg.object_id = object_id;
 	trace_cachefiles_ondemand_close(object, &req->msg);
 	return 0;
 }
@@ -457,16 +526,7 @@ static int cachefiles_ondemand_init_read_req(struct cachefiles_req *req,
 	struct cachefiles_object *object = req->object;
 	struct cachefiles_read *load = (void *)req->msg.data;
 	struct cachefiles_read_ctx *read_ctx = private;
-	int object_id = object->ondemand_id;
-
-	/* Stop enqueuing requests when daemon has closed anon_fd. */
-	if (object_id <= 0) {
-		WARN_ON_ONCE(object_id == 0);
-		pr_info_once("READ: anonymous fd closed prematurely.\n");
-		return -EIO;
-	}
 
-	req->msg.object_id = object_id;
 	load->off = read_ctx->off;
 	load->len = read_ctx->len;
 	trace_cachefiles_ondemand_read(object, &req->msg, load);
@@ -479,13 +539,16 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object)
 	struct fscache_volume *volume = object->volume->vcookie;
 	size_t volume_key_size, cookie_key_size, data_len;
 
+	if (!object->ondemand)
+		return 0;
+
 	/*
 	 * CacheFiles will firstly check the cache file under the root cache
 	 * directory. If the coherency check failed, it will fallback to
 	 * creating a new tmpfile as the cache file. Reuse the previously
 	 * allocated object ID if any.
 	 */
-	if (object->ondemand_id > 0)
+	if (cachefiles_ondemand_object_is_open(object))
 		return 0;
 
 	volume_key_size = volume->key[0] + 1;
@@ -503,6 +566,28 @@ void cachefiles_ondemand_clean_object(struct cachefiles_object *object)
 			cachefiles_ondemand_init_close_req, NULL);
 }
 
+int cachefiles_ondemand_init_obj_info(struct cachefiles_object *object,
+				struct cachefiles_volume *volume)
+{
+	if (!cachefiles_in_ondemand_mode(volume->cache))
+		return 0;
+
+	object->ondemand = kzalloc(sizeof(struct cachefiles_ondemand_info),
+					GFP_KERNEL);
+	if (!object->ondemand)
+		return -ENOMEM;
+
+	object->ondemand->object = object;
+	INIT_WORK(&object->ondemand->ondemand_work, ondemand_object_worker);
+	return 0;
+}
+
+void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *object)
+{
+	kfree(object->ondemand);
+	object->ondemand = NULL;
+}
+
 int cachefiles_ondemand_read(struct cachefiles_object *object,
 			     loff_t pos, size_t len)
 {