6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jia Zhu <zhujia.zj@xxxxxxxxxxxxx> [ Upstream commit e73fa11a356ca0905c3cc648eaacc6f0f2d2c8b3 ] Previously, in ondemand read scenario, if the anonymous fd was closed by user daemon, inflight and subsequent read requests would return EIO. As long as the device connection is not released, user daemon can hold and restore inflight requests by setting the request flag to CACHEFILES_REQ_NEW. Suggested-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx> Signed-off-by: Jia Zhu <zhujia.zj@xxxxxxxxxxxxx> Signed-off-by: Xin Yin <yinxin.x@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20231120041422.75170-6-zhujia.zj@xxxxxxxxxxxxx Reviewed-by: Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx> Reviewed-by: David Howells <dhowells@xxxxxxxxxx> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/cachefiles/daemon.c | 1 + fs/cachefiles/internal.h | 3 +++ fs/cachefiles/ondemand.c | 23 +++++++++++++++++++++++ 3 files changed, 27 insertions(+) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 7d1f456e376dd..26b487e112596 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -77,6 +77,7 @@ static const struct cachefiles_daemon_cmd cachefiles_daemon_cmds[] = { { "tag", cachefiles_daemon_tag }, #ifdef CONFIG_CACHEFILES_ONDEMAND { "copen", cachefiles_ondemand_copen }, + { "restore", cachefiles_ondemand_restore }, #endif { "", NULL } }; diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 33fe418aca770..361356d0e866a 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -304,6 +304,9 @@ extern ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args); +extern int cachefiles_ondemand_restore(struct cachefiles_cache *cache, + char *args); + extern int cachefiles_ondemand_init_object(struct cachefiles_object *object); extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object); diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index 8118649d30727..6d8f7f01a73ac 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -214,6 +214,29 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args) 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; -- 2.43.0
