From patchwork Fri Oct 22 19:05:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12578785 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 515A7C433EF for ; Fri, 22 Oct 2021 19:06:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35DE961038 for ; Fri, 22 Oct 2021 19:06:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234201AbhJVTIS (ORCPT ); Fri, 22 Oct 2021 15:08:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:21629 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234270AbhJVTIM (ORCPT ); Fri, 22 Oct 2021 15:08:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634929554; 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=kzIZ1BAQQ1+4T0HSep4AQxNCBrWEW9woi83DFXQQtz4=; b=Wp5mlSsUwaNPT0Rp8SMG2AJX6jJEktgBaBA+XwiuMApXucoxMzDS5I3nLhwfAJ2s/+nzC8 E/wEeFJkv/vmoGbJH9nP3m/InOlrkwbCN7st4IQ0i3oyWOViiYys7CigRShhqhn7eNxLGp PVvWOqJr+myMILWqyN+LyPvs9dHZy0I= 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-554-aeXJTh2LM92G2P7yPEiN8w-1; Fri, 22 Oct 2021 15:05:48 -0400 X-MC-Unique: aeXJTh2LM92G2P7yPEiN8w-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DC1C0362F8; Fri, 22 Oct 2021 19:05:46 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2F07F19D9B; Fri, 22 Oct 2021 19:05:38 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v2 28/53] fscache: Provide a function to resize a 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: Fri, 22 Oct 2021 20:05:37 +0100 Message-ID: <163492953733.1038219.11623184093542414017.stgit@warthog.procyon.org.uk> In-Reply-To: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> References: <163492911924.1038219.13107463173777870713.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Provide a function to change the size of the storage attached to a cookie, to match the size of the file being cached when it's changed by truncate or fallocate: void fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size); This acts synchronously and is expected to run under the inode lock of the caller. Signed-off-by: David Howells cc: linux-cachefs@redhat.com --- fs/fscache/internal.h | 3 +++ fs/fscache/io.c | 25 +++++++++++++++++++++++++ fs/fscache/stats.c | 9 +++++++-- include/linux/fscache-cache.h | 4 ++++ include/linux/fscache.h | 18 ++++++++++++++++++ include/trace/events/fscache.h | 25 +++++++++++++++++++++++++ 6 files changed, 82 insertions(+), 2 deletions(-) diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h index 4c45d2af7160..9ccbbd793ea3 100644 --- a/fs/fscache/internal.h +++ b/fs/fscache/internal.h @@ -88,6 +88,9 @@ extern atomic_t fscache_n_relinquishes; extern atomic_t fscache_n_relinquishes_retire; extern atomic_t fscache_n_relinquishes_dropped; +extern atomic_t fscache_n_resizes; +extern atomic_t fscache_n_resizes_null; + static inline void fscache_stat(atomic_t *stat) { atomic_inc(stat); diff --git a/fs/fscache/io.c b/fs/fscache/io.c index 5b7ecb8a205b..bc8d1ac0e85c 100644 --- a/fs/fscache/io.c +++ b/fs/fscache/io.c @@ -255,6 +255,31 @@ int fscache_set_page_dirty(struct page *page, struct fscache_cookie *cookie) } EXPORT_SYMBOL(fscache_set_page_dirty); +/* + * Change the size of a backing object. + */ +void __fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size) +{ + struct netfs_cache_resources cres; + + trace_fscache_resize(cookie, new_size); + if (fscache_begin_operation(&cres, cookie, FSCACHE_WANT_WRITE, + fscache_access_io_resize) == 0) { + fscache_stat(&fscache_n_resizes); + set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags); + + /* We cannot defer a resize as we need to do it inside the + * netfs's inode lock so that we're serialised with respect to + * writes. + */ + cookie->volume->cache->ops->resize_cookie(&cres, new_size); + fscache_end_operation(&cres); + } else { + fscache_stat(&fscache_n_resizes_null); + } +} +EXPORT_SYMBOL(__fscache_resize_cookie); + struct fscache_write_request { struct netfs_cache_resources cache_resources; struct address_space *mapping; diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c index 8d5ad6771498..225bba60b617 100644 --- a/fs/fscache/stats.c +++ b/fs/fscache/stats.c @@ -37,6 +37,9 @@ atomic_t fscache_n_relinquishes; atomic_t fscache_n_relinquishes_retire; atomic_t fscache_n_relinquishes_dropped; +atomic_t fscache_n_resizes; +atomic_t fscache_n_resizes_null; + atomic_t fscache_n_read; EXPORT_SYMBOL(fscache_n_read); atomic_t fscache_n_write; @@ -73,8 +76,10 @@ int fscache_stats_show(struct seq_file *m, void *v) seq_printf(m, "Invals : n=%u\n", atomic_read(&fscache_n_invalidates)); - seq_printf(m, "Updates: n=%u\n", - atomic_read(&fscache_n_updates)); + seq_printf(m, "Updates: n=%u rsz=%u rsn=%u\n", + atomic_read(&fscache_n_updates), + atomic_read(&fscache_n_resizes), + atomic_read(&fscache_n_resizes_null)); seq_printf(m, "Relinqs: n=%u rtr=%u drop=%u\n", atomic_read(&fscache_n_relinquishes), diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h index 6830f91ebaf4..d5f6b636175e 100644 --- a/include/linux/fscache-cache.h +++ b/include/linux/fscache-cache.h @@ -66,6 +66,10 @@ struct fscache_cache_ops { /* Withdraw an object without any cookie access counts held */ void (*withdraw_cookie)(struct fscache_cookie *cookie); + /* Change the size of a data object */ + void (*resize_cookie)(struct netfs_cache_resources *cres, + loff_t new_size); + /* Invalidate an object */ bool (*invalidate_cookie)(struct fscache_cookie *cookie); diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 2b118e517c1d..877594fc057b 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -167,6 +167,7 @@ extern struct fscache_cookie *__fscache_acquire_cookie( extern void __fscache_use_cookie(struct fscache_cookie *, bool); extern void __fscache_unuse_cookie(struct fscache_cookie *, const void *, const loff_t *); extern void __fscache_relinquish_cookie(struct fscache_cookie *, bool); +extern void __fscache_resize_cookie(struct fscache_cookie *, loff_t); extern void __fscache_invalidate(struct fscache_cookie *, const void *, loff_t, unsigned int); #ifdef FSCACHE_USE_NEW_IO_API extern int __fscache_begin_read_operation(struct netfs_cache_resources *, struct fscache_cookie *); @@ -368,6 +369,23 @@ void fscache_update_cookie(struct fscache_cookie *cookie, const void *aux_data, __fscache_update_cookie(cookie, aux_data, object_size); } +/** + * fscache_resize_cookie - Request that a cache object be resized + * @cookie: The cookie representing the cache object + * @new_size: The new size of the object (may be NULL) + * + * Request that the size of an object be changed. + * + * See Documentation/filesystems/caching/netfs-api.txt for a complete + * description. + */ +static inline +void fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size) +{ + if (fscache_cookie_enabled(cookie)) + __fscache_resize_cookie(cookie, new_size); +} + /** * fscache_invalidate - Notify cache that an object needs invalidation * @cookie: The cookie representing the cache object diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h index 63820b807494..b01784370963 100644 --- a/include/trace/events/fscache.h +++ b/include/trace/events/fscache.h @@ -77,6 +77,7 @@ enum fscache_access_trace { fscache_access_invalidate_cookie_end, fscache_access_io_not_live, fscache_access_io_read, + fscache_access_io_resize, fscache_access_io_wait, fscache_access_io_write, fscache_access_lookup_cookie, @@ -146,6 +147,7 @@ enum fscache_access_trace { EM(fscache_access_invalidate_cookie_end,"END inval ") \ EM(fscache_access_io_not_live, "END io_notl") \ EM(fscache_access_io_read, "BEGIN io_read") \ + EM(fscache_access_io_resize, "BEGIN io_resz") \ EM(fscache_access_io_wait, "WAIT io ") \ EM(fscache_access_io_write, "BEGIN io_writ") \ EM(fscache_access_lookup_cookie, "BEGIN lookup ") \ @@ -411,6 +413,29 @@ TRACE_EVENT(fscache_invalidate, __entry->cookie, __entry->new_size) ); +TRACE_EVENT(fscache_resize, + TP_PROTO(struct fscache_cookie *cookie, loff_t new_size), + + TP_ARGS(cookie, new_size), + + TP_STRUCT__entry( + __field(unsigned int, cookie ) + __field(loff_t, old_size ) + __field(loff_t, new_size ) + ), + + TP_fast_assign( + __entry->cookie = cookie->debug_id; + __entry->old_size = cookie->object_size; + __entry->new_size = new_size; + ), + + TP_printk("c=%08x os=%08llx sz=%08llx", + __entry->cookie, + __entry->old_size, + __entry->new_size) + ); + #endif /* _TRACE_FSCACHE_H */ /* This part must be outside protection */