From patchwork Mon Oct 18 15:02:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12567025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38882C433F5 for ; Mon, 18 Oct 2021 15:02:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2463F60E0C for ; Mon, 18 Oct 2021 15:02:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233594AbhJRPFE (ORCPT ); Mon, 18 Oct 2021 11:05:04 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:24041 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233378AbhJRPEl (ORCPT ); Mon, 18 Oct 2021 11:04:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634569349; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fCVZMS1f+Fc9xqMTz/jhF/KB+eLizY8P0By1uDIP188=; b=jOOinz16A4i5vITm/L7/RquSWmmO8L4CaB6CNbZ7B8qRmubgZ9xAaxY6lgaHLt7UN93286 WtJ6qXVwJanGhi1PH3zuTNmqD4s/3dQVDTwfpfv5V3+/5X56xWa+CkbYdaSing4uWJs0Wq U+ABZ0u2rRujya96LACQChhI34jLhLQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-359-Ul4T-zXEPGq-sz71ZmwD3g-1; Mon, 18 Oct 2021 11:02:24 -0400 X-MC-Unique: Ul4T-zXEPGq-sz71ZmwD3g-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CA8E3100CCC0; Mon, 18 Oct 2021 15:02:21 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id BE7D74DA31; Mon, 18 Oct 2021 15:02:14 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 48/67] fscache: Implement "will_modify" parameter on fscache_use_cookie() From: David Howells To: linux-cachefs@redhat.com Cc: dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , Matthew Wilcox , Alexander Viro , Omar Sandoval , Linus Torvalds , linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 18 Oct 2021 16:02:14 +0100 Message-ID: <163456933400.2614702.3593094196519659430.stgit@warthog.procyon.org.uk> In-Reply-To: <163456861570.2614702.14754548462706508617.stgit@warthog.procyon.org.uk> References: <163456861570.2614702.14754548462706508617.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Implement the "will_modify" parameter passed to fscache_use_cookie(). Setting this to true will henceforth cause the affected object to be marked as dirty on disk, subject to conflict resolution in the event that power failure or a crash occurs or the filesystem operates in disconnected mode. The dirty flag is removed when the cache object is discarded from memory. A cache hook is provided to prepare for writing - and this can be used to mark the object on disk. Signed-off-by: David Howells --- fs/cachefiles/interface.c | 3 +++ fs/cachefiles/internal.h | 2 +- fs/cachefiles/xattr.c | 20 ++++++++++++++++++++ fs/fscache/cookie.c | 30 +++++++++++++++++++++++++++++- include/linux/fscache-cache.h | 3 +++ include/linux/fscache.h | 2 ++ include/trace/events/cachefiles.h | 4 ++-- 7 files changed, 60 insertions(+), 4 deletions(-) diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index 751b0fec4591..96f30eba585a 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -211,6 +211,8 @@ static void cachefiles_commit_object(struct cachefiles_object *object, { bool update = false; + if (test_and_clear_bit(FSCACHE_COOKIE_LOCAL_WRITE, &object->cookie->flags)) + update = true; if (test_and_clear_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &object->cookie->flags)) update = true; if (update) @@ -461,4 +463,5 @@ const struct fscache_cache_ops cachefiles_cache_ops = { .invalidate_cookie = cachefiles_invalidate_cookie, .resize_cookie = cachefiles_resize_cookie, .begin_operation = cachefiles_begin_operation, + .prepare_to_write = cachefiles_prepare_to_write, }; diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 1d3e37bca087..83cf2ca3a763 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -239,7 +239,7 @@ extern int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file); extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, struct dentry *dentry); - +extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie); /* * error handling diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c index ba3d050a5174..30adca42883b 100644 --- a/fs/cachefiles/xattr.c +++ b/fs/cachefiles/xattr.c @@ -53,6 +53,8 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object) buf->zero_point = 0; buf->type = CACHEFILES_COOKIE_TYPE_DATA; buf->content = object->content_info; + if (test_bit(FSCACHE_COOKIE_LOCAL_WRITE, &object->cookie->flags)) + buf->content = CACHEFILES_CONTENT_DIRTY; if (len > 0) memcpy(buf->data, fscache_get_aux(object->cookie), len); @@ -145,3 +147,21 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, _leave(" = %d", ret); return ret; } + +/* + * Stick a marker on the cache object to indicate that it's dirty. + */ +void cachefiles_prepare_to_write(struct fscache_cookie *cookie) +{ + const struct cred *saved_cred; + struct cachefiles_object *object = cookie->cache_priv; + struct cachefiles_cache *cache = object->volume->cache; + + _enter("c=%08x", object->cookie->debug_id); + + if (!test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) { + cachefiles_begin_secure(cache, &saved_cred); + cachefiles_set_object_xattr(object); + cachefiles_end_secure(cache, saved_cred); + } +} diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index 70bfbd269652..1420027cfe97 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -402,12 +402,20 @@ struct fscache_cookie *__fscache_acquire_cookie( } EXPORT_SYMBOL(__fscache_acquire_cookie); +/* + * Prepare a cache object to be written to. + */ +static void fscache_prepare_to_write(struct fscache_cookie *cookie) +{ + cookie->volume->cache->ops->prepare_to_write(cookie); +} + /* * Look up a cookie to the cache. */ static void fscache_lookup_cookie(struct fscache_cookie *cookie) { - bool changed_stage = false, need_withdraw = false; + bool changed_stage = false, need_withdraw = false, prep_write = false; _enter(""); @@ -429,6 +437,7 @@ static void fscache_lookup_cookie(struct fscache_cookie *cookie) spin_lock(&cookie->lock); if (cookie->stage != FSCACHE_COOKIE_STAGE_RELINQUISHING) { + prep_write = test_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags); __fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_ACTIVE); fscache_see_cookie(cookie, fscache_cookie_see_active); changed_stage = true; @@ -436,6 +445,8 @@ static void fscache_lookup_cookie(struct fscache_cookie *cookie) spin_unlock(&cookie->lock); if (changed_stage) wake_up_cookie_stage(cookie); + if (prep_write) + fscache_prepare_to_write(cookie); out: fscache_end_cookie_access(cookie, fscache_access_lookup_cookie_end); @@ -467,6 +478,10 @@ void __fscache_use_cookie(struct fscache_cookie *cookie, bool will_modify) stage = cookie->stage; switch (stage) { case FSCACHE_COOKIE_STAGE_QUIESCENT: + if (will_modify) { + set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags); + set_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags); + } if (!fscache_begin_volume_access(cookie->volume, fscache_access_lookup_cookie)) break; @@ -484,8 +499,18 @@ void __fscache_use_cookie(struct fscache_cookie *cookie, bool will_modify) case FSCACHE_COOKIE_STAGE_LOOKING_UP: case FSCACHE_COOKIE_STAGE_CREATING: + if (will_modify) + set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags); + break; case FSCACHE_COOKIE_STAGE_ACTIVE: case FSCACHE_COOKIE_STAGE_INVALIDATING: + if (will_modify && + !test_and_set_bit(FSCACHE_COOKIE_LOCAL_WRITE, &cookie->flags)) { + set_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags); + queue = true; + } + break; + case FSCACHE_COOKIE_STAGE_FAILED: case FSCACHE_COOKIE_STAGE_WITHDRAWING: break; @@ -551,6 +576,8 @@ static void __fscache_cookie_worker(struct fscache_cookie *cookie) again: switch (READ_ONCE(cookie->stage)) { case FSCACHE_COOKIE_STAGE_ACTIVE: + if (test_and_clear_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags)) + fscache_prepare_to_write(cookie); break; case FSCACHE_COOKIE_STAGE_LOOKING_UP: @@ -591,6 +618,7 @@ static void __fscache_cookie_worker(struct fscache_cookie *cookie) clear_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags); clear_bit(FSCACHE_COOKIE_DO_WITHDRAW, &cookie->flags); clear_bit(FSCACHE_COOKIE_DO_COMMIT, &cookie->flags); + clear_bit(FSCACHE_COOKIE_DO_PREP_TO_WRITE, &cookie->flags); set_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags); fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_QUIESCENT); break; diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h index 2e7265e24df6..889ae37fae0f 100644 --- a/include/linux/fscache-cache.h +++ b/include/linux/fscache-cache.h @@ -76,6 +76,9 @@ struct fscache_cache_ops { /* Begin an operation for the netfs lib */ bool (*begin_operation)(struct netfs_cache_resources *cres, enum fscache_want_stage want_stage); + + /* Prepare to write to a live cache object */ + void (*prepare_to_write)(struct fscache_cookie *cookie); }; static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache) diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 8148193045cd..8ab691e52cc5 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -125,10 +125,12 @@ struct fscache_cookie { #define FSCACHE_COOKIE_NEEDS_UPDATE 4 /* T if attrs have been updated */ #define FSCACHE_COOKIE_HAS_BEEN_CACHED 5 /* T if cookie needs withdraw-on-relinq */ #define FSCACHE_COOKIE_DISABLED 6 /* T if cookie has been disabled */ +#define FSCACHE_COOKIE_LOCAL_WRITE 7 /* T if cookie has been modified locally */ #define FSCACHE_COOKIE_NACC_ELEVATED 8 /* T if n_accesses is incremented */ #define FSCACHE_COOKIE_DO_RELINQUISH 9 /* T if this cookie needs relinquishment */ #define FSCACHE_COOKIE_DO_WITHDRAW 10 /* T if this cookie needs withdrawing */ #define FSCACHE_COOKIE_DO_COMMIT 11 /* T if this cookie needs committing */ +#define FSCACHE_COOKIE_DO_PREP_TO_WRITE 12 /* T if cookie needs write preparation */ enum fscache_cookie_stage stage; u8 advice; /* FSCACHE_ADV_* */ diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h index a7b31b248f2d..11447b20fc83 100644 --- a/include/trace/events/cachefiles.h +++ b/include/trace/events/cachefiles.h @@ -340,7 +340,7 @@ TRACE_EVENT(cachefiles_mark_inactive, TRACE_EVENT(cachefiles_coherency, TP_PROTO(struct cachefiles_object *obj, ino_t ino, - int content, + enum cachefiles_content content, enum cachefiles_coherency_trace why), TP_ARGS(obj, ino, content, why), @@ -349,7 +349,7 @@ TRACE_EVENT(cachefiles_coherency, TP_STRUCT__entry( __field(unsigned int, obj ) __field(enum cachefiles_coherency_trace, why ) - __field(int, content ) + __field(enum cachefiles_content, content ) __field(u64, ino ) ),