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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 5C3E2180005 X-Stat-Signature: 7fi91xo93aerfeje88xhh6uab78t5y5k X-HE-Tag: 1788559560-453589 X-HE-Meta: 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 5f79aqtc 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add documentation for dependencies between FDs preserved by File Handlers. This supplements the previously added liveupdate_get_token_outgoing() and liveupdate_get_file_incoming() internal APIs to allow File Handlers to resolve dependencies. Signed-off-by: Samiullah Khawaja --- kernel/liveupdate/luo_file.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/kernel/liveupdate/luo_file.c b/kernel/liveupdate/luo_file.c index dbae0715220b..0a4994377c98 100644 --- a/kernel/liveupdate/luo_file.c +++ b/kernel/liveupdate/luo_file.c @@ -91,6 +91,21 @@ * again later. If the issue cannot be resolved, these resources will be held * by LUO until the next live update cycle, at which point they will be * discarded. + * + * Dependencies: + * + * Preserved files may have dependencies on other files that also need to be + * preserved during a live update. A file handler can resolve these dependencies + * by querying the token of the dependency. That token can then be serialized + * and used to fetch the dependency during the retrieve() callback in the next + * kernel. + * + * Some of these dependencies can be resolved late during File Handler freeze() + * callback, but some of these might need resolution during File Handler + * preserve() callback based on the constraints such as immutability and + * performance. This introduces an order of preservation. Note that the order of + * preservation of dependencies can be safely relaxed later, but it cannot be + * enforced later. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt -- 2.55.0.1003.g10538fe699-goog