From patchwork Fri Oct 22 19:07:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12578843 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 2D730C433FE for ; Fri, 22 Oct 2021 19:08:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0EFDA610D0 for ; Fri, 22 Oct 2021 19:08:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234150AbhJVTLA (ORCPT ); Fri, 22 Oct 2021 15:11:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:37727 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234325AbhJVTKO (ORCPT ); Fri, 22 Oct 2021 15:10:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634929676; 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=S1I1g+jMJjTNPxktPPq0ahC5WNvciw0RepqZVH6shlk=; b=DahrPFRbr2PEXh2EXULGE+7ouBko1fmet4XOovqqAzygKpT5OK1JDTKRXVtJ+PGn926EPa 0MZ/UV0XtEq3OQGLhS5rrmDLIrblKPVI25Eq/702VI1r4OABdkB7vx6AvND383qFL7n0lv RdqSBqyDOb3IVwKqlHAIFVjpV9BTwH0= 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-430-4gofB3QPM3ScrQxNSaT1TQ-1; Fri, 22 Oct 2021 15:07:52 -0400 X-MC-Unique: 4gofB3QPM3ScrQxNSaT1TQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8F940806688; Fri, 22 Oct 2021 19:07:50 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id ED90B60C04; Fri, 22 Oct 2021 19:07:43 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v2 38/53] cachefiles: Implement data storage object handling 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 20:07:43 +0100 Message-ID: <163492966313.1038219.16694710752489269856.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 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Implement the handling of data storage objects, including the following pieces: (1) An S_KERNEL_FILE inode flag is provided that a kernel service, e.g. cachefiles, can set to ward off other kernel services and drivers (including itself) from using files it is actively using. (2) Allocation of a cachefiles_object struct for storing state. (3) Rendering the binary key into something that can be used as a filename. A number of encoding are considered, including plain text, hex rendering of arrays of le32 or be32 words or a base64 encoding. (4) Lookup and creation of a file on disk, using a tmpfile if the file isn't yet present. The file is then opened, sized for DIO and the file handle is attached to the cachefiles_object struct. The inode is marked S_KERNEL_FILE to indicate that it's in use by a kernel service. (5) Reading and checking the xattr on a file to check coherency, (6) Resizing an object, using truncate and/or fallocate to adjust the object. (7) Invalidation of an object, creating a tmpfile and switching the file pointer in the cachefiles object. (8) Committing a file to disk, including setting the coherency xattr on it and, if necessary, creating a hard link to it. Note that this would be a good place to use Omar Sandoval's vfs_link() with AT_LINK_REPLACE[1] as I may have to unlink an old file before I can link a tmpfile into place. (9) Withdrawal of open objects when a cache is being withdrawn or a cookie is relinquished. This involves committing or discarding the file. (10) Culling a file at the behest of the daemon. (11) A method by which the daemon can query to see if a file is in use by the cache. Changes ======= ver #2) - Disabled a debugging statement. Signed-off-by: David Howells Link: https://lore.kernel.org/r/163363935000.1980952.15279841414072653108.stgit@warthog.procyon.org.uk [1] cc: linux-cachefs@redhat.com --- fs/cachefiles/Makefile | 4 fs/cachefiles/bind.c | 32 ++ fs/cachefiles/daemon.c | 46 ++ fs/cachefiles/interface.c | 438 ++++++++++++++++++++++ fs/cachefiles/internal.h | 57 +++ fs/cachefiles/key.c | 142 +++++++ fs/cachefiles/main.c | 16 + fs/cachefiles/namei.c | 739 +++++++++++++++++++++++++++++++++++++ fs/cachefiles/xattr.c | 181 +++++++++ include/linux/fs.h | 1 include/trace/events/cachefiles.h | 354 ++++++++++++++++++ include/trace/events/fscache.h | 4 12 files changed, 2010 insertions(+), 4 deletions(-) create mode 100644 fs/cachefiles/key.c create mode 100644 fs/cachefiles/xattr.c diff --git a/fs/cachefiles/Makefile b/fs/cachefiles/Makefile index 607f7c684a97..5dd99ca8df05 100644 --- a/fs/cachefiles/Makefile +++ b/fs/cachefiles/Makefile @@ -7,10 +7,12 @@ cachefiles-y := \ bind.o \ daemon.o \ interface.o \ + key.o \ main.o \ namei.o \ security.o \ - volume.o + volume.o \ + xattr.o cachefiles-$(CONFIG_CACHEFILES_ERROR_INJECTION) += error_inject.o diff --git a/fs/cachefiles/bind.c b/fs/cachefiles/bind.c index 70924997b0cc..59c9d141f1fe 100644 --- a/fs/cachefiles/bind.c +++ b/fs/cachefiles/bind.c @@ -236,6 +236,36 @@ static int cachefiles_daemon_add_cache(struct cachefiles_cache *cache) return ret; } +/* + * Mark all the objects as being out of service and queue them all for cleanup. + */ +static void cachefiles_withdraw_objects(struct cachefiles_cache *cache) +{ + struct cachefiles_object *object; + unsigned int count = 0; + + _enter(""); + + spin_lock(&cache->object_list_lock); + + while (!list_empty(&cache->object_list)) { + object = list_first_entry(&cache->object_list, + struct cachefiles_object, cache_link); + cachefiles_see_object(object, cachefiles_obj_see_withdrawal); + list_del_init(&object->cache_link); + fscache_withdraw_cookie(object->cookie); + count++; + if ((count & 63) == 0) { + spin_unlock(&cache->object_list_lock); + cond_resched(); + spin_lock(&cache->object_list_lock); + } + } + + spin_unlock(&cache->object_list_lock); + _leave(" [%u objs]", count); +} + /* * Withdraw volumes. */ @@ -276,7 +306,7 @@ static void cachefiles_withdraw_cache(struct cachefiles_cache *cache) /* we now have to destroy all the active objects pertaining to this * cache - which we do by passing them off to thread pool to be * disposed of */ - // PLACEHOLDER: Withdraw objects + cachefiles_withdraw_objects(cache); /* wait for all extant objects to finish their outstanding operations * and go away */ diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index c23d22a5d4a6..50ec292c7213 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -548,6 +548,10 @@ static int cachefiles_daemon_tag(struct cachefiles_cache *cache, char *args) */ static int cachefiles_daemon_cull(struct cachefiles_cache *cache, char *args) { + struct path path; + const struct cred *saved_cred; + int ret; + _enter(",%s", args); if (strchr(args, '/')) @@ -563,7 +567,24 @@ static int cachefiles_daemon_cull(struct cachefiles_cache *cache, char *args) return -EIO; } - return -EOPNOTSUPP; // PLACEHOLDER: Implement culling + /* extract the directory dentry from the cwd */ + get_fs_pwd(current->fs, &path); + + if (!d_can_lookup(path.dentry)) + goto notdir; + + cachefiles_begin_secure(cache, &saved_cred); + ret = cachefiles_cull(cache, path.dentry, args); + cachefiles_end_secure(cache, saved_cred); + + path_put(&path); + _leave(" = %d", ret); + return ret; + +notdir: + path_put(&path); + pr_err("cull command requires dirfd to be a directory\n"); + return -ENOTDIR; inval: pr_err("cull command requires dirfd and filename\n"); @@ -599,6 +620,10 @@ static int cachefiles_daemon_debug(struct cachefiles_cache *cache, char *args) */ static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) { + struct path path; + const struct cred *saved_cred; + int ret; + //_enter(",%s", args); if (strchr(args, '/')) @@ -614,7 +639,24 @@ static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) return -EIO; } - return -EOPNOTSUPP; // PLACEHOLDER: Implement check in use + /* extract the directory dentry from the cwd */ + get_fs_pwd(current->fs, &path); + + if (!d_can_lookup(path.dentry)) + goto notdir; + + cachefiles_begin_secure(cache, &saved_cred); + ret = cachefiles_check_in_use(cache, path.dentry, args); + cachefiles_end_secure(cache, saved_cred); + + path_put(&path); + //_leave(" = %d", ret); + return ret; + +notdir: + path_put(&path); + pr_err("inuse command requires dirfd to be a directory\n"); + return -ENOTDIR; inval: pr_err("inuse command requires dirfd and filename\n"); diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index 8624ee52b98b..b4a0bd2e803f 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -13,6 +13,310 @@ #include #include "internal.h" +static atomic_t cachefiles_object_debug_id; + +static int cachefiles_attr_changed(struct cachefiles_object *object); + +/* + * Allocate a cache object record. + */ +static +struct cachefiles_object *cachefiles_alloc_object(struct fscache_cookie *cookie) +{ + struct fscache_volume *vcookie = cookie->volume; + struct cachefiles_object *object; + struct cachefiles_volume *volume = vcookie->cache_priv; + int n_accesses; + + _enter("{%s},%x,", vcookie->key, cookie->debug_id); + + object = kmem_cache_zalloc(cachefiles_object_jar, cachefiles_gfp); + if (!object) + return NULL; + + atomic_set(&object->usage, 1); + + spin_lock_init(&object->lock); + INIT_LIST_HEAD(&object->cache_link); + object->volume = volume; + object->debug_id = atomic_inc_return(&cachefiles_object_debug_id); + object->cookie = fscache_get_cookie(cookie, fscache_cookie_get_attach_object); + + atomic_inc(&vcookie->cache->object_count); + trace_cachefiles_ref(object->debug_id, cookie->debug_id, 1, + cachefiles_obj_new); + + /* Get a ref on the cookie and keep its n_accesses counter raised by 1 + * to prevent wakeups from transitioning it to 0 until we're + * withdrawing caching services from it. + */ + n_accesses = atomic_inc_return(&cookie->n_accesses); + trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref), + n_accesses, fscache_access_cache_pin); + set_bit(FSCACHE_COOKIE_NACC_ELEVATED, &cookie->flags); + return object; +} + +/* + * Attempt to look up the nominated node in this cache + */ +static bool cachefiles_lookup_cookie(struct fscache_cookie *cookie) +{ + struct cachefiles_object *object; + struct cachefiles_cache *cache = cookie->volume->cache->cache_priv; + const struct cred *saved_cred; + bool success; + + object = cachefiles_alloc_object(cookie); + if (!object) + goto fail; + + _enter("{OBJ%x}", object->debug_id); + + if (!cachefiles_cook_key(object)) + goto fail_put; + + cookie->cache_priv = object; + + /* look up the key, creating any missing bits */ + cachefiles_begin_secure(cache, &saved_cred); + success = cachefiles_look_up_object(object); + cachefiles_end_secure(cache, saved_cred); + + if (!success) + goto fail_withdraw; + + cachefiles_see_object(object, cachefiles_obj_see_lookup_cookie); + + spin_lock(&cache->object_list_lock); + list_add(&object->cache_link, &cache->object_list); + spin_unlock(&cache->object_list_lock); + cachefiles_attr_changed(object); + _leave(" = t"); + return true; + +fail_withdraw: + cachefiles_see_object(object, cachefiles_obj_see_lookup_failed); + clear_bit(FSCACHE_COOKIE_IS_CACHING, &object->flags); + fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_FAILED); + _debug("failed c=%08x o=%08x", cookie->debug_id, object->debug_id); + /* The caller holds an access count on the cookie, so we need them to + * drop it before we can withdraw the object. + */ + return false; + +fail_put: + cachefiles_put_object(object, cachefiles_obj_put_alloc_fail); +fail: + return false; +} + +/* + * Note that an object has been seen. + */ +void cachefiles_see_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why) +{ + trace_cachefiles_ref(object->debug_id, object->cookie->debug_id, + atomic_read(&object->usage), why); +} + +/* + * increment the usage count on an inode object (may fail if unmounting) + */ +struct cachefiles_object *cachefiles_grab_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why) +{ + int u; + + u = atomic_inc_return(&object->usage); + trace_cachefiles_ref(object->debug_id, object->cookie->debug_id, u, why); + return object; +} + +/* + * Shorten the backing object to discard any dirty data and free up + * any unused granules. + */ +static bool cachefiles_shorten_object(struct cachefiles_object *object, + struct file *file, loff_t new_size) +{ + struct cachefiles_cache *cache = object->volume->cache; + struct inode *inode = file_inode(file); + loff_t i_size, dio_size; + int ret; + + dio_size = round_up(new_size, CACHEFILES_DIO_BLOCK_SIZE); + i_size = i_size_read(inode); + + trace_cachefiles_trunc(object, inode, i_size, dio_size, + cachefiles_trunc_shrink); + ret = cachefiles_inject_remove_error(); + if (ret == 0) + ret = vfs_truncate(&file->f_path, dio_size); + if (ret < 0) { + trace_cachefiles_io_error(object, file_inode(file), ret, + cachefiles_trace_trunc_error); + cachefiles_io_error_obj(object, "Trunc-to-size failed %d", ret); + cachefiles_remove_object_xattr(cache, object, file->f_path.dentry); + return false; + } + + if (new_size < dio_size) { + trace_cachefiles_trunc(object, inode, dio_size, new_size, + cachefiles_trunc_dio_adjust); + ret = cachefiles_inject_write_error(); + if (ret == 0) + ret = vfs_fallocate(file, FALLOC_FL_ZERO_RANGE, + new_size, dio_size); + if (ret < 0) { + trace_cachefiles_io_error(object, file_inode(file), ret, + cachefiles_trace_fallocate_error); + cachefiles_io_error_obj(object, "Trunc-to-dio-size failed %d", ret); + cachefiles_remove_object_xattr(cache, object, file->f_path.dentry); + return false; + } + } + + return true; +} + +/* + * Resize the backing object. + */ +static void cachefiles_resize_cookie(struct netfs_cache_resources *cres, + loff_t new_size) +{ + struct cachefiles_object *object = cachefiles_cres_object(cres); + struct cachefiles_cache *cache = object->volume->cache; + struct fscache_cookie *cookie = object->cookie; + const struct cred *saved_cred; + struct file *file = cachefiles_cres_file(cres); + loff_t old_size = cookie->object_size; + + _enter("%llu->%llu", old_size, new_size); + + if (new_size < old_size) { + cachefiles_begin_secure(cache, &saved_cred); + cachefiles_shorten_object(object, file, new_size); + cachefiles_end_secure(cache, saved_cred); + object->cookie->object_size = new_size; + return; + } + + /* The file is being expanded. We don't need to do anything + * particularly. cookie->initial_size doesn't change and so the point + * at which we have to download before doesn't change. + */ + cookie->object_size = new_size; +} + +/* + * Commit changes to the object as we drop it. + */ +static void cachefiles_commit_object(struct cachefiles_object *object, + struct cachefiles_cache *cache) +{ + 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) + cachefiles_set_object_xattr(object); + + if (test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) + cachefiles_commit_tmpfile(cache, object); +} + +/* + * Finalise and object and close the VFS structs that we have. + */ +static void cachefiles_clean_up_object(struct cachefiles_object *object, + struct cachefiles_cache *cache) +{ + if (test_bit(FSCACHE_COOKIE_RETIRED, &object->cookie->flags)) { + if (!test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) { + cachefiles_see_object(object, cachefiles_obj_see_clean_delete); + _debug("- inval object OBJ%x", object->debug_id); + cachefiles_delete_object(object, FSCACHE_OBJECT_WAS_RETIRED); + } else { + cachefiles_see_object(object, cachefiles_obj_see_clean_drop_tmp); + _debug("- inval object OBJ%x tmpfile", object->debug_id); + } + } else { + cachefiles_see_object(object, cachefiles_obj_see_clean_commit); + cachefiles_commit_object(object, cache); + } + + cachefiles_unmark_inode_in_use(object, object->file); + if (object->file) { + fput(object->file); + object->file = NULL; + } +} + +/* + * Withdraw caching for a cookie. + */ +static void cachefiles_withdraw_cookie(struct fscache_cookie *cookie) +{ + struct cachefiles_object *object = cookie->cache_priv; + struct cachefiles_cache *cache = object->volume->cache; + const struct cred *saved_cred; + + _enter("o=%x", object->debug_id); + cachefiles_see_object(object, cachefiles_obj_see_withdraw_cookie); + + if (!list_empty(&object->cache_link)) { + spin_lock(&cache->object_list_lock); + cachefiles_see_object(object, cachefiles_obj_see_withdrawal); + list_del_init(&object->cache_link); + spin_unlock(&cache->object_list_lock); + } + + if (object->file) { + cachefiles_begin_secure(cache, &saved_cred); + cachefiles_clean_up_object(object, cache); + cachefiles_end_secure(cache, saved_cred); + } + + cookie->cache_priv = NULL; + cachefiles_put_object(object, cachefiles_obj_put_detach); +} + +/* + * dispose of a reference to an object + */ +void cachefiles_put_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why) +{ + unsigned int object_debug_id = object->debug_id; + unsigned int cookie_debug_id = object->cookie->debug_id; + struct fscache_cache *cache; + int u; + + u = atomic_dec_return(&object->usage); + trace_cachefiles_ref(object_debug_id, cookie_debug_id, u, why); + if (u == 0) { + _debug("- kill object OBJ%x", object_debug_id); + + ASSERTCMP(object->file, ==, NULL); + + kfree(object->d_name); + + cache = object->volume->cache->cache; + fscache_put_cookie(object->cookie, fscache_cookie_put_object); + object->cookie = NULL; + kmem_cache_free(cachefiles_object_jar, object); + if (atomic_dec_and_test(&cache->object_count)) + wake_up_all(&cachefiles_clearance_wq); + } + + _leave(""); +} + /* * sync a cache */ @@ -37,8 +341,142 @@ void cachefiles_sync_cache(struct cachefiles_cache *cache) ret); } +/* + * notification the attributes on an object have changed + * - called with reads/writes excluded by FS-Cache + */ +static int cachefiles_attr_changed(struct cachefiles_object *object) +{ + struct cachefiles_cache *cache = object->volume->cache; + const struct cred *saved_cred; + struct iattr newattrs; + struct file *file = object->file; + uint64_t ni_size; + loff_t oi_size; + int ret; + + ni_size = object->cookie->object_size; + ni_size = round_up(ni_size, CACHEFILES_DIO_BLOCK_SIZE); + + _enter("{OBJ%x},[%llu]", + object->debug_id, (unsigned long long) ni_size); + + if (!file) + return -ENOBUFS; + + oi_size = i_size_read(file_inode(file)); + if (oi_size == ni_size) + return 0; + + cachefiles_begin_secure(cache, &saved_cred); + inode_lock(file_inode(file)); + + /* if there's an extension to a partial page at the end of the backing + * file, we need to discard the partial page so that we pick up new + * data after it */ + if (oi_size & ~PAGE_MASK && ni_size > oi_size) { + _debug("discard tail %llx", oi_size); + newattrs.ia_valid = ATTR_SIZE; + newattrs.ia_size = oi_size & PAGE_MASK; + ret = cachefiles_inject_remove_error(); + if (ret == 0) + ret = notify_change(&init_user_ns, file->f_path.dentry, + &newattrs, NULL); + if (ret < 0) + goto truncate_failed; + } + + newattrs.ia_valid = ATTR_SIZE; + newattrs.ia_size = ni_size; + ret = cachefiles_inject_write_error(); + if (ret == 0) + ret = notify_change(&init_user_ns, file->f_path.dentry, + &newattrs, NULL); + +truncate_failed: + inode_unlock(file_inode(file)); + cachefiles_end_secure(cache, saved_cred); + + if (ret < 0) + trace_cachefiles_io_error(NULL, file_inode(file), ret, + cachefiles_trace_notify_change_error); + if (ret == -EIO) { + cachefiles_io_error_obj(object, "Size set failed"); + ret = -ENOBUFS; + } + + _leave(" = %d", ret); + return ret; +} + +/* + * Invalidate the storage associated with a cookie. + */ +static bool cachefiles_invalidate_cookie(struct fscache_cookie *cookie) +{ + struct cachefiles_object *object = cookie->cache_priv; + struct file *new_file, *old_file; + bool old_tmpfile; + + _enter("o=%x,[%llu]", object->debug_id, object->cookie->object_size); + + old_tmpfile = test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); + + if (!object->file) { + fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_ACTIVE); + _leave(" = t [light]"); + return true; + } + + new_file = cachefiles_create_tmpfile(object); + if (IS_ERR(new_file)) + goto failed; + + /* Substitute the VFS target */ + _debug("sub"); + spin_lock(&object->lock); + + old_file = object->file; + object->file = new_file; + object->content_info = CACHEFILES_CONTENT_NO_DATA; + set_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); + set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &object->cookie->flags); + + spin_unlock(&object->lock); + _debug("subbed"); + + /* Allow I/O to take place again */ + fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_ACTIVE); + + if (old_file) { + if (!old_tmpfile) { + struct cachefiles_volume *volume = object->volume; + struct dentry *fan = volume->fanout[(u8)object->key_hash]; + + inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); + cachefiles_bury_object(volume->cache, object, fan, + old_file->f_path.dentry, + FSCACHE_OBJECT_INVALIDATED); + } + fput(old_file); + } + + _leave(" = t"); + return true; + +failed: + fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_FAILED); + _leave(" = f"); + return false; +} + const struct fscache_cache_ops cachefiles_cache_ops = { .name = "cachefiles", .acquire_volume = cachefiles_acquire_volume, .free_volume = cachefiles_free_volume, + .lookup_cookie = cachefiles_lookup_cookie, + .withdraw_cookie = cachefiles_withdraw_cookie, + .invalidate_cookie = cachefiles_invalidate_cookie, + .resize_cookie = cachefiles_resize_cookie, + .prepare_to_write = cachefiles_prepare_to_write, }; diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 828b888a8bf3..3fa23710fc6f 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -19,6 +19,8 @@ #include #include +#define CACHEFILES_DIO_BLOCK_SIZE 4096 + struct cachefiles_cache; struct cachefiles_object; @@ -27,6 +29,8 @@ extern unsigned cachefiles_debug; #define CACHEFILES_DEBUG_KLEAVE 2 #define CACHEFILES_DEBUG_KDEBUG 4 +#define cachefiles_gfp (__GFP_RECLAIM | __GFP_NORETRY | __GFP_NOMEMALLOC) + enum cachefiles_content { /* These values are saved on disk */ CACHEFILES_CONTENT_NO_DATA = 0, /* No content stored */ @@ -114,6 +118,18 @@ struct cachefiles_cache { #include +static inline +struct file *cachefiles_cres_file(struct netfs_cache_resources *cres) +{ + return cres->cache_priv2; +} + +static inline +struct cachefiles_object *cachefiles_cres_object(struct netfs_cache_resources *cres) +{ + return fscache_cres_cookie(cres)->cache_priv; +} + /* * note change of state for daemon */ @@ -182,15 +198,45 @@ static inline int cachefiles_inject_remove_error(void) * interface.c */ extern const struct fscache_cache_ops cachefiles_cache_ops; +extern void cachefiles_see_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why); +extern struct cachefiles_object *cachefiles_grab_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why); +extern void cachefiles_put_object(struct cachefiles_object *object, + enum cachefiles_obj_ref_trace why); extern void cachefiles_sync_cache(struct cachefiles_cache *cache); +/* + * key.c + */ +extern bool cachefiles_cook_key(struct cachefiles_object *object); + /* * namei.c */ +extern void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, + struct file *file); +extern int cachefiles_bury_object(struct cachefiles_cache *cache, + struct cachefiles_object *object, + struct dentry *dir, + struct dentry *rep, + enum fscache_why_object_killed why); +extern int cachefiles_delete_object(struct cachefiles_object *object, + enum fscache_why_object_killed why); +extern bool cachefiles_look_up_object(struct cachefiles_object *object); extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, struct dentry *dir, const char *name); +extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, + char *filename); + +extern int cachefiles_check_in_use(struct cachefiles_cache *cache, + struct dentry *dir, char *filename); +extern struct file *cachefiles_create_tmpfile(struct cachefiles_object *object); +extern bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache, + struct cachefiles_object *object); + /* * security.c */ @@ -218,6 +264,17 @@ void cachefiles_acquire_volume(struct fscache_volume *volume); void cachefiles_free_volume(struct fscache_volume *volume); void cachefiles_withdraw_volume(struct cachefiles_volume *volume); +/* + * xattr.c + */ +extern int cachefiles_set_object_xattr(struct cachefiles_object *object); +extern int cachefiles_check_auxdata(struct cachefiles_object *object, + struct file *file); +extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, + struct cachefiles_object *object, + struct dentry *dentry); +extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie); + /* * error handling */ diff --git a/fs/cachefiles/key.c b/fs/cachefiles/key.c new file mode 100644 index 000000000000..10f2be29f892 --- /dev/null +++ b/fs/cachefiles/key.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Key to pathname encoder + * + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include "internal.h" + +static const char cachefiles_charmap[64] = + "0123456789" /* 0 - 9 */ + "abcdefghijklmnopqrstuvwxyz" /* 10 - 35 */ + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" /* 36 - 61 */ + "_-" /* 62 - 63 */ + ; + +static const char cachefiles_filecharmap[256] = { + /* we skip space and tab and control chars */ + [33 ... 46] = 1, /* '!' -> '.' */ + /* we skip '/' as it's significant to pathwalk */ + [48 ... 127] = 1, /* '0' -> '~' */ +}; + +static inline unsigned int how_many_hex_digits(unsigned int x) +{ + return x ? round_up(ilog2(x) + 1, 4) / 4 : 0; +} + +/* + * turn the raw key into something cooked + * - the key may be up to NAME_MAX in length (including the length word) + * - "base64" encode the strange keys, mapping 3 bytes of raw to four of + * cooked + * - need to cut the cooked key into 252 char lengths (189 raw bytes) + */ +bool cachefiles_cook_key(struct cachefiles_object *object) +{ + const u8 *key = fscache_get_key(object->cookie), *kend; + unsigned char sum, ch; + unsigned int acc, i, n, nle, nbe, keylen = object->cookie->key_len; + unsigned int b64len, len, print, pad; + char *name, sep; + + _enter(",%u,%*phN", keylen, keylen, key); + + BUG_ON(keylen > NAME_MAX - 3); + + sum = 0; + print = 1; + for (i = 0; i < keylen; i++) { + ch = key[i]; + sum += ch; + print &= cachefiles_filecharmap[ch]; + } + object->key_hash = sum; + + /* If the path is usable ASCII, then we render it directly */ + if (print) { + len = 1 + keylen + 1; + name = kmalloc(len, cachefiles_gfp); + if (!name) + return false; + + name[0] = 'D'; /* Data object type, string encoding */ + name[1 + keylen] = 0; + memcpy(name + 1, key, keylen); + goto success; + } + + /* See if it makes sense to encode it as "hex,hex,hex" for each 32-bit + * chunk. We rely on the key having been padded out to a whole number + * of 32-bit words. + */ + n = round_up(keylen, 4); + nbe = nle = 0; + for (i = 0; i < n; i += 4) { + u32 be = be32_to_cpu(*(__be32 *)(key + i)); + u32 le = le32_to_cpu(*(__le32 *)(key + i)); + + nbe += 1 + how_many_hex_digits(be); + nle += 1 + how_many_hex_digits(le); + } + + b64len = DIV_ROUND_UP(keylen, 3); + pad = b64len * 3 - keylen; + b64len = 2 + b64len * 4; /* Length if we base64-encode it */ + _debug("len=%u nbe=%u nle=%u b64=%u", keylen, nbe, nle, b64len); + if (nbe < b64len || nle < b64len) { + unsigned int nlen = min(nbe, nle) + 1; + name = kmalloc(nlen, cachefiles_gfp); + if (!name) + return false; + sep = (nbe <= nle) ? 'S' : 'T'; /* Encoding indicator */ + len = 0; + for (i = 0; i < n; i += 4) { + u32 x; + if (nbe <= nle) + x = be32_to_cpu(*(__be32 *)(key + i)); + else + x = le32_to_cpu(*(__le32 *)(key + i)); + name[len++] = sep; + if (x != 0) + len += snprintf(name + len, nlen - len, "%x", x); + sep = ','; + } + goto success; + } + + /* We need to base64-encode it */ + name = kmalloc(b64len + 1, cachefiles_gfp); + if (!name) + return false; + + name[0] = 'E'; + name[1] = '0' + pad; + len = 2; + kend = key + keylen; + do { + acc = *key++; + if (key < kend) { + acc |= *key++ << 8; + if (key < kend) + acc |= *key++ << 16; + } + + name[len++] = cachefiles_charmap[acc & 63]; + acc >>= 6; + name[len++] = cachefiles_charmap[acc & 63]; + acc >>= 6; + name[len++] = cachefiles_charmap[acc & 63]; + acc >>= 6; + name[len++] = cachefiles_charmap[acc & 63]; + } while (key < kend); + +success: + name[len] = 0; + object->d_name = name; + object->d_name_len = len; + _leave(" = %s", object->d_name); + return true; +} diff --git a/fs/cachefiles/main.c b/fs/cachefiles/main.c index 22581099236b..7a459074d715 100644 --- a/fs/cachefiles/main.c +++ b/fs/cachefiles/main.c @@ -31,6 +31,8 @@ MODULE_DESCRIPTION("Mounted-filesystem based cache"); MODULE_AUTHOR("Red Hat, Inc."); MODULE_LICENSE("GPL"); +struct kmem_cache *cachefiles_object_jar; + static struct miscdevice cachefiles_dev = { .minor = MISC_DYNAMIC_MINOR, .name = "cachefiles", @@ -52,9 +54,22 @@ static int __init cachefiles_init(void) if (ret < 0) goto error_dev; + /* create an object jar */ + ret = -ENOMEM; + cachefiles_object_jar = + kmem_cache_create("cachefiles_object_jar", + sizeof(struct cachefiles_object), + 0, SLAB_HWCACHE_ALIGN, NULL); + if (!cachefiles_object_jar) { + pr_notice("Failed to allocate an object jar\n"); + goto error_object_jar; + } + pr_info("Loaded\n"); return 0; +error_object_jar: + misc_deregister(&cachefiles_dev); error_dev: cachefiles_unregister_error_injection(); error_einj: @@ -71,6 +86,7 @@ static void __exit cachefiles_exit(void) { pr_info("Unloading\n"); + kmem_cache_destroy(cachefiles_object_jar); misc_deregister(&cachefiles_dev); cachefiles_unregister_error_injection(); } diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 69915dde0a83..ad87fb28b602 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -18,6 +18,431 @@ #include #include "internal.h" +/* + * Mark the backing file as being a cache file if it's not already in use so. + */ +static bool cachefiles_mark_inode_in_use(struct cachefiles_object *object, + struct dentry *dentry) +{ + struct inode *inode = d_backing_inode(dentry); + bool can_use = false; + + _enter(",%x", object->debug_id); + + inode_lock(inode); + + if (!(inode->i_flags & S_KERNEL_FILE)) { + inode->i_flags |= S_KERNEL_FILE; + trace_cachefiles_mark_active(object, inode); + can_use = true; + } else { + pr_notice("cachefiles: Inode already in use: %pD\n", object->file); + } + + inode_unlock(inode); + return can_use; +} + +/* + * Unmark a backing inode. + */ +void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, + struct file *file) +{ + struct inode *inode = file_inode(file); + + if (!inode) + return; + + inode_lock(inode); + inode->i_flags &= ~S_KERNEL_FILE; + inode_unlock(inode); + trace_cachefiles_mark_inactive(object, inode); +} + +/* + * Mark an object as being inactive. + */ +static void cachefiles_mark_object_inactive(struct cachefiles_object *object, + struct file *file) +{ + struct cachefiles_cache *cache = object->volume->cache; + blkcnt_t i_blocks = file_inode(file)->i_blocks; + + /* This object can now be culled, so we need to let the daemon know + * that there is something it can remove if it needs to. + */ + atomic_long_add(i_blocks, &cache->b_released); + if (atomic_inc_return(&cache->f_released)) + cachefiles_state_changed(cache); +} + +/* + * delete an object representation from the cache + * - file backed objects are unlinked + * - directory backed objects are stuffed into the graveyard for userspace to + * delete + */ +int cachefiles_bury_object(struct cachefiles_cache *cache, + struct cachefiles_object *object, + struct dentry *dir, + struct dentry *rep, + enum fscache_why_object_killed why) +{ + struct dentry *grave, *trap; + struct path path, path_to_graveyard; + char nbuffer[8 + 8 + 1]; + int ret; + + _enter(",'%pd','%pd'", dir, rep); + + if (rep->d_parent != dir) { + inode_unlock(d_inode(dir)); + _leave(" = -ESTALE"); + return -ESTALE; + } + + /* non-directories can just be unlinked */ + if (!d_is_dir(rep)) { + _debug("unlink stale object"); + + path.mnt = cache->mnt; + path.dentry = dir; + ret = security_path_unlink(&path, rep); + if (ret < 0) { + cachefiles_io_error(cache, "Unlink security error"); + } else { + trace_cachefiles_unlink(object, rep, why); + dget(rep); /* Stop the dentry being negated if it's + * only pinned by a file struct. + */ + ret = cachefiles_inject_remove_error(); + if (ret == 0) + ret = vfs_unlink(&init_user_ns, d_inode(dir), rep, NULL); + dput(rep); + } + + inode_unlock(d_inode(dir)); + + if (ret < 0) { + trace_cachefiles_vfs_error(object, d_inode(dir), ret, + cachefiles_trace_unlink_error); + if (ret == -EIO) + cachefiles_io_error(cache, "Unlink failed"); + } + + _leave(" = %d", ret); + return ret; + } + + /* directories have to be moved to the graveyard */ + _debug("move stale object to graveyard"); + inode_unlock(d_inode(dir)); + +try_again: + /* first step is to make up a grave dentry in the graveyard */ + sprintf(nbuffer, "%08x%08x", + (uint32_t) ktime_get_real_seconds(), + (uint32_t) atomic_inc_return(&cache->gravecounter)); + + /* do the multiway lock magic */ + trap = lock_rename(cache->graveyard, dir); + + /* do some checks before getting the grave dentry */ + if (rep->d_parent != dir || IS_DEADDIR(d_inode(rep))) { + /* the entry was probably culled when we dropped the parent dir + * lock */ + unlock_rename(cache->graveyard, dir); + _leave(" = 0 [culled?]"); + return 0; + } + + if (!d_can_lookup(cache->graveyard)) { + unlock_rename(cache->graveyard, dir); + cachefiles_io_error(cache, "Graveyard no longer a directory"); + return -EIO; + } + + if (trap == rep) { + unlock_rename(cache->graveyard, dir); + cachefiles_io_error(cache, "May not make directory loop"); + return -EIO; + } + + if (d_mountpoint(rep)) { + unlock_rename(cache->graveyard, dir); + cachefiles_io_error(cache, "Mountpoint in cache"); + return -EIO; + } + + grave = lookup_one_len(nbuffer, cache->graveyard, strlen(nbuffer)); + if (IS_ERR(grave)) { + unlock_rename(cache->graveyard, dir); + trace_cachefiles_vfs_error(object, d_inode(cache->graveyard), + PTR_ERR(grave), + cachefiles_trace_lookup_error); + + if (PTR_ERR(grave) == -ENOMEM) { + _leave(" = -ENOMEM"); + return -ENOMEM; + } + + cachefiles_io_error(cache, "Lookup error %ld", PTR_ERR(grave)); + return -EIO; + } + + if (d_is_positive(grave)) { + unlock_rename(cache->graveyard, dir); + dput(grave); + grave = NULL; + cond_resched(); + goto try_again; + } + + if (d_mountpoint(grave)) { + unlock_rename(cache->graveyard, dir); + dput(grave); + cachefiles_io_error(cache, "Mountpoint in graveyard"); + return -EIO; + } + + /* target should not be an ancestor of source */ + if (trap == grave) { + unlock_rename(cache->graveyard, dir); + dput(grave); + cachefiles_io_error(cache, "May not make directory loop"); + return -EIO; + } + + /* attempt the rename */ + path.mnt = cache->mnt; + path.dentry = dir; + path_to_graveyard.mnt = cache->mnt; + path_to_graveyard.dentry = cache->graveyard; + ret = security_path_rename(&path, rep, &path_to_graveyard, grave, 0); + if (ret < 0) { + cachefiles_io_error(cache, "Rename security error %d", ret); + } else { + struct renamedata rd = { + .old_mnt_userns = &init_user_ns, + .old_dir = d_inode(dir), + .old_dentry = rep, + .new_mnt_userns = &init_user_ns, + .new_dir = d_inode(cache->graveyard), + .new_dentry = grave, + }; + trace_cachefiles_rename(object, rep, grave, why); + ret = cachefiles_inject_read_error(); + if (ret == 0) + ret = vfs_rename(&rd); + if (ret != 0) + trace_cachefiles_vfs_error(object, d_inode(dir), + PTR_ERR(grave), + cachefiles_trace_rename_error); + if (ret != 0 && ret != -ENOMEM) + cachefiles_io_error(cache, + "Rename failed with error %d", ret); + } + + unlock_rename(cache->graveyard, dir); + dput(grave); + _leave(" = 0"); + return 0; +} + +static int cachefiles_unlink(struct cachefiles_object *object, + struct dentry *fan, struct dentry *dentry, + enum fscache_why_object_killed why) +{ + struct path path = { + .mnt = object->volume->cache->mnt, + .dentry = fan, + }; + int ret; + + trace_cachefiles_unlink(object, dentry, why); + ret = security_path_unlink(&path, dentry); + if (ret == 0) + ret = cachefiles_inject_remove_error(); + if (ret == 0) + ret = vfs_unlink(&init_user_ns, d_backing_inode(fan), dentry, NULL); + if (ret != 0) + trace_cachefiles_vfs_error(object, d_backing_inode(fan), ret, + cachefiles_trace_unlink_error); + return ret; +} + +/* + * Delete a cache file. + */ +int cachefiles_delete_object(struct cachefiles_object *object, + enum fscache_why_object_killed why) +{ + struct cachefiles_volume *volume = object->volume; + struct dentry *dentry = object->file->f_path.dentry; + struct dentry *fan = volume->fanout[(u8)object->key_hash]; + int ret; + + _enter(",OBJ%x{%pD}", object->debug_id, object->file); + + /* Stop the dentry being negated if it's only pinned by a file struct. */ + dget(dentry); + + inode_lock_nested(d_backing_inode(fan), I_MUTEX_PARENT); + ret = cachefiles_unlink(object, fan, dentry, why); + inode_unlock(d_backing_inode(fan)); + dput(dentry); + + if (ret < 0) + trace_cachefiles_vfs_error(object, d_backing_inode(fan), ret, + cachefiles_trace_unlink_error); + if (ret < 0 && ret != -ENOENT) + cachefiles_io_error(volume->cache, "Unlink failed"); + return ret; +} + +/* + * Create a new file. + */ +static bool cachefiles_create_file(struct cachefiles_object *object) +{ + struct file *file; + int ret; + + ret = cachefiles_has_space(object->volume->cache, 1, 0); + if (ret < 0) + return false; + + file = cachefiles_create_tmpfile(object); + if (IS_ERR(file)) + return false; + + set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &object->cookie->flags); + set_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); + _debug("create -> %pD{ino=%lu}", file, file_inode(file)->i_ino); + object->file = file; + return true; +} + +/* + * Open an existing file, checking its attributes and replacing it if it is + * stale. + */ +static bool cachefiles_open_file(struct cachefiles_object *object, + struct dentry *dentry) +{ + struct cachefiles_cache *cache = object->volume->cache; + struct file *file; + struct path path; + int ret; + + _enter("%pd", dentry); + + if (!cachefiles_mark_inode_in_use(object, dentry)) + return false; + + /* We need to open a file interface onto a data file now as we can't do + * it on demand because writeback called from do_exit() sees + * current->fs == NULL - which breaks d_path() called from ext4 open. + */ + path.mnt = cache->mnt; + path.dentry = dentry; + file = open_with_fake_path(&path, O_RDWR | O_LARGEFILE | O_DIRECT, + d_backing_inode(dentry), cache->cache_cred); + if (IS_ERR(file)) { + trace_cachefiles_vfs_error(object, d_backing_inode(dentry), + PTR_ERR(file), + cachefiles_trace_open_error); + goto error; + } + + if (unlikely(!file->f_op->read_iter) || + unlikely(!file->f_op->write_iter)) { + pr_notice("Cache does not support read_iter and write_iter\n"); + goto error_fput; + } + _debug("file -> %pd positive", dentry); + + ret = cachefiles_check_auxdata(object, file); + if (ret < 0) + goto check_failed; + + object->file = file; + + /* Always update the atime on an object we've just looked up (this is + * used to keep track of culling, and atimes are only updated by read, + * write and readdir but not lookup or open). + */ + touch_atime(&file->f_path); + dput(dentry); + return true; + +check_failed: + fscache_cookie_lookup_negative(object->cookie); + cachefiles_unmark_inode_in_use(object, file); + cachefiles_mark_object_inactive(object, file); + if (ret == -ESTALE) { + fput(file); + dput(dentry); + return cachefiles_create_file(object); + } +error_fput: + fput(file); +error: + dput(dentry); + return false; +} + +/* + * walk from the parent object to the child object through the backing + * filesystem, creating directories as we go + */ +bool cachefiles_look_up_object(struct cachefiles_object *object) +{ + struct cachefiles_volume *volume = object->volume; + struct dentry *dentry, *fan = volume->fanout[(u8)object->key_hash]; + int ret; + + _enter("OBJ%x,%s,", object->debug_id, object->d_name); + + /* Look up path "cache/vol/fanout/file". */ + ret = cachefiles_inject_read_error(); + if (ret == 0) + dentry = lookup_positive_unlocked(object->d_name, fan, + object->d_name_len); + else + dentry = ERR_PTR(ret); + trace_cachefiles_lookup(object, dentry); + if (IS_ERR(dentry)) { + if (dentry == ERR_PTR(-ENOENT)) + goto new_file; + if (dentry == ERR_PTR(-EIO)) + cachefiles_io_error_obj(object, "Lookup failed"); + return false; + } + + if (!d_is_reg(dentry)) { + pr_err("%pd is not a file\n", dentry); + inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); + ret = cachefiles_bury_object(volume->cache, object, fan, dentry, + FSCACHE_OBJECT_IS_WEIRD); + dput(dentry); + if (ret < 0) + return false; + goto new_file; + } + + if (!cachefiles_open_file(object, dentry)) + return false; + + _leave(" = t [%lu]", file_inode(object->file)->i_ino); + return true; + +new_file: + fscache_cookie_lookup_negative(object->cookie); + return cachefiles_create_file(object); +} + /* * get a subdirectory */ @@ -131,3 +556,317 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, _leave(" = -ENOMEM"); return ERR_PTR(-ENOMEM); } + +/* + * find out if an object is in use or not + * - if finds object and it's not in use: + * - returns a pointer to the object and a reference on it + * - returns with the directory locked + */ +static struct dentry *cachefiles_check_active(struct cachefiles_cache *cache, + struct dentry *dir, + char *filename) +{ + struct dentry *victim; + int ret; + + //_enter(",%pd/,%s", + // dir, filename); + + /* look up the victim */ + inode_lock_nested(d_inode(dir), I_MUTEX_PARENT); + + victim = lookup_one_len(filename, dir, strlen(filename)); + if (IS_ERR(victim)) + goto lookup_error; + + //_debug("victim -> %pd %s", + // victim, d_backing_inode(victim) ? "positive" : "negative"); + + /* if the object is no longer there then we probably retired the object + * at the netfs's request whilst the cull was in progress + */ + if (d_is_negative(victim)) { + inode_unlock(d_inode(dir)); + dput(victim); + _leave(" = -ENOENT [absent]"); + return ERR_PTR(-ENOENT); + } + + //_leave(" = %pd", victim); + return victim; + +lookup_error: + inode_unlock(d_inode(dir)); + ret = PTR_ERR(victim); + if (ret == -ENOENT) { + /* file or dir now absent - probably retired by netfs */ + _leave(" = -ESTALE [absent]"); + return ERR_PTR(-ESTALE); + } + + if (ret == -EIO) { + cachefiles_io_error(cache, "Lookup failed"); + } else if (ret != -ENOMEM) { + pr_err("Internal error: %d\n", ret); + ret = -EIO; + } + + _leave(" = %d", ret); + return ERR_PTR(ret); +} + +/* + * cull an object if it's not in use + * - called only by cache manager daemon + */ +int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, + char *filename) +{ + struct dentry *victim; + struct inode *inode; + int ret; + + _enter(",%pd/,%s", dir, filename); + + victim = cachefiles_check_active(cache, dir, filename); + if (IS_ERR(victim)) + return PTR_ERR(victim); + + /* check to see if someone is using this object */ + inode = d_inode(victim); + inode_lock(inode); + if (inode->i_flags & S_KERNEL_FILE) { + ret = -EBUSY; + } else { + inode->i_flags |= S_KERNEL_FILE; + ret = 0; + } + inode_unlock(inode); + if (ret < 0) + goto error_unlock; + + _debug("victim -> %pd %s", + victim, d_backing_inode(victim) ? "positive" : "negative"); + + /* okay... the victim is not being used so we can cull it + * - start by marking it as stale + */ + _debug("victim is cullable"); + + ret = cachefiles_remove_object_xattr(cache, NULL, victim); + if (ret < 0) + goto error_unlock; + + /* actually remove the victim (drops the dir mutex) */ + _debug("bury"); + + ret = cachefiles_bury_object(cache, NULL, dir, victim, + FSCACHE_OBJECT_WAS_CULLED); + if (ret < 0) + goto error; + + dput(victim); + _leave(" = 0"); + return 0; + +error_unlock: + inode_unlock(d_inode(dir)); +error: + dput(victim); + if (ret == -ENOENT) { + /* file or dir now absent - probably retired by netfs */ + _leave(" = -ESTALE [absent]"); + return -ESTALE; + } + + if (ret != -ENOMEM) { + pr_err("Internal error: %d\n", ret); + ret = -EIO; + } + + _leave(" = %d", ret); + return ret; +} + +/* + * find out if an object is in use or not + * - called only by cache manager daemon + * - returns -EBUSY or 0 to indicate whether an object is in use or not + */ +int cachefiles_check_in_use(struct cachefiles_cache *cache, struct dentry *dir, + char *filename) +{ + struct dentry *victim; + int ret = 0; + + //_enter(",%pd/,%s", + // dir, filename); + + victim = cachefiles_check_active(cache, dir, filename); + if (IS_ERR(victim)) + return PTR_ERR(victim); + + inode_unlock(d_inode(dir)); + if (d_inode(victim)->i_flags & S_KERNEL_FILE) + ret = -EBUSY; + dput(victim); + //_leave(" = 0"); + return ret; +} + +/* + * Create a temporary file and leave it unattached and un-xattr'd until the + * time comes to discard the object from memory. + */ +struct file *cachefiles_create_tmpfile(struct cachefiles_object *object) +{ + struct cachefiles_volume *volume = object->volume; + struct cachefiles_cache *cache = volume->cache; + const struct cred *saved_cred; + struct dentry *fan = volume->fanout[(u8)object->key_hash]; + struct file *file; + struct path path; + uint64_t ni_size = object->cookie->object_size; + long ret; + + ni_size = round_up(ni_size, CACHEFILES_DIO_BLOCK_SIZE); + + cachefiles_begin_secure(cache, &saved_cred); + + path.mnt = cache->mnt; + ret = cachefiles_inject_write_error(); + if (ret == 0) + path.dentry = vfs_tmpfile(&init_user_ns, fan, S_IFREG, O_RDWR); + else + path.dentry = ERR_PTR(ret); + if (IS_ERR(path.dentry)) { + trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(path.dentry), + cachefiles_trace_tmpfile_error); + if (PTR_ERR(path.dentry) == -EIO) + cachefiles_io_error_obj(object, "Failed to create tmpfile"); + file = ERR_CAST(path.dentry); + goto out; + } + + trace_cachefiles_tmpfile(object, d_backing_inode(path.dentry)); + + if (!cachefiles_mark_inode_in_use(object, path.dentry)) { + file = ERR_PTR(-EBUSY); + goto out_dput; + } + + if (ni_size > 0) { + trace_cachefiles_trunc(object, d_backing_inode(path.dentry), 0, ni_size, + cachefiles_trunc_expand_tmpfile); + ret = cachefiles_inject_write_error(); + if (ret == 0) + ret = vfs_truncate(&path, ni_size); + if (ret < 0) { + trace_cachefiles_vfs_error( + object, d_backing_inode(path.dentry), ret, + cachefiles_trace_trunc_error); + file = ERR_PTR(ret); + goto out_dput; + } + } + + file = open_with_fake_path(&path, O_RDWR | O_LARGEFILE | O_DIRECT, + d_backing_inode(path.dentry), cache->cache_cred); + if (IS_ERR(file)) { + trace_cachefiles_vfs_error(object, d_backing_inode(path.dentry), + PTR_ERR(file), + cachefiles_trace_open_error); + goto out_dput; + } + if (unlikely(!file->f_op->read_iter) || + unlikely(!file->f_op->write_iter)) { + fput(file); + pr_notice("Cache does not support read_iter and write_iter\n"); + file = ERR_PTR(-EINVAL); + } + +out_dput: + dput(path.dentry); +out: + cachefiles_end_secure(cache, saved_cred); + return file; +} + +/* + * Attempt to link a temporary file into its rightful place in the cache. + */ +bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache, + struct cachefiles_object *object) +{ + struct cachefiles_volume *volume = object->volume; + struct dentry *dentry, *fan = volume->fanout[(u8)object->key_hash]; + bool success = false; + int ret; + + _enter(",%pD", object->file); + + inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); + ret = cachefiles_inject_read_error(); + if (ret == 0) + dentry = lookup_one_len(object->d_name, fan, object->d_name_len); + else + dentry = ERR_PTR(ret); + if (IS_ERR(dentry)) { + trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(dentry), + cachefiles_trace_lookup_error); + _debug("lookup fail %ld", PTR_ERR(dentry)); + goto out_unlock; + } + + if (!d_is_negative(dentry)) { + if (d_backing_inode(dentry) == file_inode(object->file)) { + success = true; + goto out_dput; + } + + ret = cachefiles_unlink(object, fan, dentry, FSCACHE_OBJECT_IS_STALE); + if (ret < 0) { + trace_cachefiles_vfs_error(object, d_inode(fan), ret, + cachefiles_trace_unlink_error); + goto out_dput; + } + + dput(dentry); + ret = cachefiles_inject_read_error(); + if (ret == 0) + dentry = lookup_one_len(object->d_name, fan, object->d_name_len); + else + dentry = ERR_PTR(ret); + if (IS_ERR(dentry)) { + trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(dentry), + cachefiles_trace_lookup_error); + _debug("lookup fail %ld", PTR_ERR(dentry)); + goto out_unlock; + } + } + + ret = cachefiles_inject_read_error(); + if (ret == 0) + ret = vfs_link(object->file->f_path.dentry, &init_user_ns, + d_inode(fan), dentry, NULL); + if (ret < 0) { + trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(dentry), + cachefiles_trace_link_error); + _debug("link fail %d", ret); + } else { + trace_cachefiles_link(object, file_inode(object->file)); + spin_lock(&object->lock); + /* TODO: Do we want to switch the file pointer to the new dentry? */ + clear_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); + spin_unlock(&object->lock); + success = true; + } + +out_dput: + dput(dentry); +out_unlock: + inode_unlock(d_inode(fan)); + _leave(" = %u", success); + return success; +} diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c new file mode 100644 index 000000000000..0601c46a22ef --- /dev/null +++ b/fs/cachefiles/xattr.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* CacheFiles extended attribute management + * + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +#define CACHEFILES_COOKIE_TYPE_DATA 1 + +struct cachefiles_xattr { + __be64 object_size; /* Actual size of the object */ + __be64 zero_point; /* Size after which server has no data not written by us */ + __u8 type; /* Type of object */ + __u8 content; /* Content presence (enum cachefiles_content) */ + __u8 data[]; /* netfs coherency data */ +} __packed; + +static const char cachefiles_xattr_cache[] = + XATTR_USER_PREFIX "CacheFiles.cache"; + +/* + * set the state xattr on a cache file + */ +int cachefiles_set_object_xattr(struct cachefiles_object *object) +{ + struct cachefiles_xattr *buf; + struct dentry *dentry; + struct file *file = object->file; + unsigned int len = object->cookie->aux_len; + int ret; + + if (!file) + return -ESTALE; + dentry = file->f_path.dentry; + + _enter("%x,#%d", object->debug_id, len); + + buf = kmalloc(sizeof(struct cachefiles_xattr) + len, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + buf->object_size = cpu_to_be64(object->cookie->object_size); + 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); + + ret = cachefiles_inject_write_error(); + if (ret == 0) + ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, + buf, sizeof(struct cachefiles_xattr) + len, 0); + if (ret < 0) { + trace_cachefiles_vfs_error(object, file_inode(file), ret, + cachefiles_trace_setxattr_error); + trace_cachefiles_coherency(object, file_inode(file)->i_ino, + buf->content, + cachefiles_coherency_set_fail); + if (ret != -ENOMEM) + cachefiles_io_error_obj( + object, + "Failed to set xattr with error %d", ret); + } else { + trace_cachefiles_coherency(object, file_inode(file)->i_ino, + buf->content, + cachefiles_coherency_set_ok); + } + + kfree(buf); + _leave(" = %d", ret); + return ret; +} + +/* + * check the consistency between the backing cache and the FS-Cache cookie + */ +int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file) +{ + struct cachefiles_xattr *buf; + struct dentry *dentry = file->f_path.dentry; + unsigned int len = object->cookie->aux_len, tlen; + const void *p = fscache_get_aux(object->cookie); + enum cachefiles_coherency_trace why; + ssize_t xlen; + int ret = -ESTALE; + + tlen = sizeof(struct cachefiles_xattr) + len; + buf = kmalloc(tlen, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + xlen = cachefiles_inject_read_error(); + if (xlen == 0) + xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, buf, tlen); + if (xlen != tlen) { + if (xlen < 0) + trace_cachefiles_vfs_error(object, file_inode(file), xlen, + cachefiles_trace_getxattr_error); + if (xlen == -EIO) + cachefiles_io_error_obj( + object, + "Failed to read aux with error %zd", xlen); + why = cachefiles_coherency_check_xattr; + } else if (buf->type != CACHEFILES_COOKIE_TYPE_DATA) { + why = cachefiles_coherency_check_type; + } else if (memcmp(buf->data, p, len) != 0) { + why = cachefiles_coherency_check_aux; + } else if (be64_to_cpu(buf->object_size) != object->cookie->object_size) { + why = cachefiles_coherency_check_objsize; + } else if (buf->content == CACHEFILES_CONTENT_DIRTY) { + // TODO: Begin conflict resolution + pr_warn("Dirty object in cache\n"); + why = cachefiles_coherency_check_dirty; + } else { + why = cachefiles_coherency_check_ok; + ret = 0; + } + + trace_cachefiles_coherency(object, file_inode(file)->i_ino, + buf->content, why); + kfree(buf); + return ret; +} + +/* + * remove the object's xattr to mark it stale + */ +int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, + struct cachefiles_object *object, + struct dentry *dentry) +{ + int ret; + + ret = cachefiles_inject_remove_error(); + if (ret == 0) + ret = vfs_removexattr(&init_user_ns, dentry, cachefiles_xattr_cache); + if (ret < 0) { + trace_cachefiles_vfs_error(object, d_inode(dentry), ret, + cachefiles_trace_remxattr_error); + if (ret == -ENOENT || ret == -ENODATA) + ret = 0; + else if (ret != -ENOMEM) + cachefiles_io_error(cache, + "Can't remove xattr from %lu" + " (error %d)", + d_backing_inode(dentry)->i_ino, -ret); + } + + _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/include/linux/fs.h b/include/linux/fs.h index 908ea452a2cf..336739fed3e9 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2250,6 +2250,7 @@ struct super_operations { #define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */ #define S_CASEFOLD (1 << 15) /* Casefolded file */ #define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */ +#define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */ /* * Note that nosuid etc flags are inode-specific: setting some file-system diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h index 9bd5a8a60801..5412991ab5e1 100644 --- a/include/trace/events/cachefiles.h +++ b/include/trace/events/cachefiles.h @@ -18,6 +18,60 @@ #ifndef __CACHEFILES_DECLARE_TRACE_ENUMS_ONCE_ONLY #define __CACHEFILES_DECLARE_TRACE_ENUMS_ONCE_ONLY +enum cachefiles_obj_ref_trace { + cachefiles_obj_get_ioreq, + cachefiles_obj_new, + cachefiles_obj_put_alloc_fail, + cachefiles_obj_put_detach, + cachefiles_obj_put_ioreq, + cachefiles_obj_see_clean_commit, + cachefiles_obj_see_clean_delete, + cachefiles_obj_see_clean_drop_tmp, + cachefiles_obj_see_lookup_cookie, + cachefiles_obj_see_lookup_failed, + cachefiles_obj_see_withdraw_cookie, + cachefiles_obj_see_withdrawal, +}; + +enum fscache_why_object_killed { + FSCACHE_OBJECT_IS_STALE, + FSCACHE_OBJECT_IS_WEIRD, + FSCACHE_OBJECT_INVALIDATED, + FSCACHE_OBJECT_NO_SPACE, + FSCACHE_OBJECT_WAS_RETIRED, + FSCACHE_OBJECT_WAS_CULLED, +}; + +enum cachefiles_coherency_trace { + cachefiles_coherency_check_aux, + cachefiles_coherency_check_content, + cachefiles_coherency_check_dirty, + cachefiles_coherency_check_len, + cachefiles_coherency_check_objsize, + cachefiles_coherency_check_ok, + cachefiles_coherency_check_type, + cachefiles_coherency_check_xattr, + cachefiles_coherency_set_fail, + cachefiles_coherency_set_ok, +}; + +enum cachefiles_trunc_trace { + cachefiles_trunc_dio_adjust, + cachefiles_trunc_expand_tmpfile, + cachefiles_trunc_shrink, +}; + +enum cachefiles_prepare_read_trace { + cachefiles_trace_read_after_eof, + cachefiles_trace_read_found_hole, + cachefiles_trace_read_found_part, + cachefiles_trace_read_have_data, + cachefiles_trace_read_no_data, + cachefiles_trace_read_no_file, + cachefiles_trace_read_seek_error, + cachefiles_trace_read_seek_nxio, +}; + enum cachefiles_error_trace { cachefiles_trace_fallocate_error, cachefiles_trace_getxattr_error, @@ -43,6 +97,55 @@ enum cachefiles_error_trace { /* * Define enum -> string mappings for display. */ +#define cachefiles_obj_kill_traces \ + EM(FSCACHE_OBJECT_IS_STALE, "stale") \ + EM(FSCACHE_OBJECT_IS_WEIRD, "weird") \ + EM(FSCACHE_OBJECT_INVALIDATED, "inval") \ + EM(FSCACHE_OBJECT_NO_SPACE, "no_space") \ + EM(FSCACHE_OBJECT_WAS_RETIRED, "was_retired") \ + E_(FSCACHE_OBJECT_WAS_CULLED, "was_culled") + +#define cachefiles_obj_ref_traces \ + EM(cachefiles_obj_get_ioreq, "GET ioreq") \ + EM(cachefiles_obj_new, "NEW obj") \ + EM(cachefiles_obj_put_alloc_fail, "PUT alloc_fail") \ + EM(cachefiles_obj_put_detach, "PUT detach") \ + EM(cachefiles_obj_put_ioreq, "PUT ioreq") \ + EM(cachefiles_obj_see_clean_commit, "SEE clean_commit") \ + EM(cachefiles_obj_see_clean_delete, "SEE clean_delete") \ + EM(cachefiles_obj_see_clean_drop_tmp, "SEE clean_drop_tmp") \ + EM(cachefiles_obj_see_lookup_cookie, "SEE lookup_cookie") \ + EM(cachefiles_obj_see_lookup_failed, "SEE lookup_failed") \ + EM(cachefiles_obj_see_withdraw_cookie, "SEE withdraw_cookie") \ + E_(cachefiles_obj_see_withdrawal, "SEE withdrawal") + +#define cachefiles_coherency_traces \ + EM(cachefiles_coherency_check_aux, "BAD aux ") \ + EM(cachefiles_coherency_check_content, "BAD cont") \ + EM(cachefiles_coherency_check_dirty, "BAD dirt") \ + EM(cachefiles_coherency_check_len, "BAD len ") \ + EM(cachefiles_coherency_check_objsize, "BAD osiz") \ + EM(cachefiles_coherency_check_ok, "OK ") \ + EM(cachefiles_coherency_check_type, "BAD type") \ + EM(cachefiles_coherency_check_xattr, "BAD xatt") \ + EM(cachefiles_coherency_set_fail, "SET fail") \ + E_(cachefiles_coherency_set_ok, "SET ok ") + +#define cachefiles_trunc_traces \ + EM(cachefiles_trunc_dio_adjust, "DIOADJ") \ + EM(cachefiles_trunc_expand_tmpfile, "EXPTMP") \ + E_(cachefiles_trunc_shrink, "SHRINK") + +#define cachefiles_prepare_read_traces \ + EM(cachefiles_trace_read_after_eof, "after-eof ") \ + EM(cachefiles_trace_read_found_hole, "found-hole") \ + EM(cachefiles_trace_read_found_part, "found-part") \ + EM(cachefiles_trace_read_have_data, "have-data ") \ + EM(cachefiles_trace_read_no_data, "no-data ") \ + EM(cachefiles_trace_read_no_file, "no-file ") \ + EM(cachefiles_trace_read_seek_error, "seek-error") \ + E_(cachefiles_trace_read_seek_nxio, "seek-enxio") + #define cachefiles_error_traces \ EM(cachefiles_trace_fallocate_error, "fallocate") \ EM(cachefiles_trace_getxattr_error, "getxattr") \ @@ -71,6 +174,11 @@ enum cachefiles_error_trace { #define EM(a, b) TRACE_DEFINE_ENUM(a); #define E_(a, b) TRACE_DEFINE_ENUM(a); +cachefiles_obj_kill_traces; +cachefiles_obj_ref_traces; +cachefiles_coherency_traces; +cachefiles_trunc_traces; +cachefiles_prepare_read_traces; cachefiles_error_traces; /* @@ -83,6 +191,252 @@ cachefiles_error_traces; #define E_(a, b) { a, b } +TRACE_EVENT(cachefiles_ref, + TP_PROTO(unsigned int object_debug_id, + unsigned int cookie_debug_id, + int usage, + enum cachefiles_obj_ref_trace why), + + TP_ARGS(object_debug_id, cookie_debug_id, usage, why), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, cookie ) + __field(enum cachefiles_obj_ref_trace, why ) + __field(int, usage ) + ), + + TP_fast_assign( + __entry->obj = object_debug_id; + __entry->cookie = cookie_debug_id; + __entry->usage = usage; + __entry->why = why; + ), + + TP_printk("c=%08x o=%08x u=%d %s", + __entry->cookie, __entry->obj, __entry->usage, + __print_symbolic(__entry->why, cachefiles_obj_ref_traces)) + ); + +TRACE_EVENT(cachefiles_lookup, + TP_PROTO(struct cachefiles_object *obj, + struct dentry *de), + + TP_ARGS(obj, de), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(short, error ) + __field(unsigned long, ino ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->ino = (!IS_ERR(de) && d_backing_inode(de) ? + d_backing_inode(de)->i_ino : 0); + __entry->error = IS_ERR(de) ? PTR_ERR(de) : 0; + ), + + TP_printk("o=%08x i=%lx e=%d", + __entry->obj, __entry->ino, __entry->error) + ); + +TRACE_EVENT(cachefiles_tmpfile, + TP_PROTO(struct cachefiles_object *obj, struct inode *backer), + + TP_ARGS(obj, backer), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, backer ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->backer = backer->i_ino; + ), + + TP_printk("o=%08x b=%08x", + __entry->obj, + __entry->backer) + ); + +TRACE_EVENT(cachefiles_link, + TP_PROTO(struct cachefiles_object *obj, struct inode *backer), + + TP_ARGS(obj, backer), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, backer ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->backer = backer->i_ino; + ), + + TP_printk("o=%08x b=%08x", + __entry->obj, + __entry->backer) + ); + +TRACE_EVENT(cachefiles_unlink, + TP_PROTO(struct cachefiles_object *obj, + struct dentry *de, + enum fscache_why_object_killed why), + + TP_ARGS(obj, de, why), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(struct dentry *, de ) + __field(enum fscache_why_object_killed, why ) + ), + + TP_fast_assign( + __entry->obj = obj ? obj->debug_id : UINT_MAX; + __entry->de = de; + __entry->why = why; + ), + + TP_printk("o=%08x d=%p w=%s", + __entry->obj, __entry->de, + __print_symbolic(__entry->why, cachefiles_obj_kill_traces)) + ); + +TRACE_EVENT(cachefiles_rename, + TP_PROTO(struct cachefiles_object *obj, + struct dentry *de, + struct dentry *to, + enum fscache_why_object_killed why), + + TP_ARGS(obj, de, to, why), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(struct dentry *, de ) + __field(struct dentry *, to ) + __field(enum fscache_why_object_killed, why ) + ), + + TP_fast_assign( + __entry->obj = obj ? obj->debug_id : UINT_MAX; + __entry->de = de; + __entry->to = to; + __entry->why = why; + ), + + TP_printk("o=%08x d=%p t=%p w=%s", + __entry->obj, __entry->de, __entry->to, + __print_symbolic(__entry->why, cachefiles_obj_kill_traces)) + ); + +TRACE_EVENT(cachefiles_mark_active, + TP_PROTO(struct cachefiles_object *obj, + struct inode *inode), + + TP_ARGS(obj, inode), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(ino_t, inode ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->inode = inode->i_ino; + ), + + TP_printk("o=%08x i=%lx", + __entry->obj, __entry->inode) + ); + +TRACE_EVENT(cachefiles_mark_inactive, + TP_PROTO(struct cachefiles_object *obj, + struct inode *inode), + + TP_ARGS(obj, inode), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(ino_t, inode ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->inode = inode->i_ino; + ), + + TP_printk("o=%08x i=%lx", + __entry->obj, __entry->inode) + ); + +TRACE_EVENT(cachefiles_coherency, + TP_PROTO(struct cachefiles_object *obj, + ino_t ino, + enum cachefiles_content content, + enum cachefiles_coherency_trace why), + + TP_ARGS(obj, ino, content, why), + + /* Note that obj may be NULL */ + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(enum cachefiles_coherency_trace, why ) + __field(enum cachefiles_content, content ) + __field(u64, ino ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->why = why; + __entry->content = content; + __entry->ino = ino; + ), + + TP_printk("o=%08x %s i=%llx c=%u", + __entry->obj, + __print_symbolic(__entry->why, cachefiles_coherency_traces), + __entry->ino, + __entry->content) + ); + +TRACE_EVENT(cachefiles_trunc, + TP_PROTO(struct cachefiles_object *obj, struct inode *backer, + loff_t from, loff_t to, enum cachefiles_trunc_trace why), + + TP_ARGS(obj, backer, from, to, why), + + TP_STRUCT__entry( + __field(unsigned int, obj ) + __field(unsigned int, backer ) + __field(enum cachefiles_trunc_trace, why ) + __field(loff_t, from ) + __field(loff_t, to ) + ), + + TP_fast_assign( + __entry->obj = obj->debug_id; + __entry->backer = backer->i_ino; + __entry->from = from; + __entry->to = to; + __entry->why = why; + ), + + TP_printk("o=%08x b=%08x %s l=%llx->%llx", + __entry->obj, + __entry->backer, + __print_symbolic(__entry->why, cachefiles_trunc_traces), + __entry->from, + __entry->to) + ); + TRACE_EVENT(cachefiles_vfs_error, TP_PROTO(struct cachefiles_object *obj, struct inode *backer, int error, enum cachefiles_error_trace where), diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h index b01784370963..3ebb874b5f0f 100644 --- a/include/trace/events/fscache.h +++ b/include/trace/events/fscache.h @@ -48,6 +48,7 @@ enum fscache_volume_trace { enum fscache_cookie_trace { fscache_cookie_collision, fscache_cookie_discard, + fscache_cookie_get_attach_object, fscache_cookie_get_end_access, fscache_cookie_get_hash_collision, fscache_cookie_get_inval_work, @@ -56,6 +57,7 @@ enum fscache_cookie_trace { fscache_cookie_new_acquire, fscache_cookie_put_hash_collision, fscache_cookie_put_lru, + fscache_cookie_put_object, fscache_cookie_put_over_queued, fscache_cookie_put_relinquish, fscache_cookie_put_withdrawn, @@ -119,6 +121,7 @@ enum fscache_access_trace { #define fscache_cookie_traces \ EM(fscache_cookie_collision, "*COLLIDE*") \ EM(fscache_cookie_discard, "DISCARD ") \ + EM(fscache_cookie_get_attach_object, "GET attch") \ EM(fscache_cookie_get_hash_collision, "GET hcoll") \ EM(fscache_cookie_get_end_access, "GQ endac") \ EM(fscache_cookie_get_inval_work, "GQ inval") \ @@ -127,6 +130,7 @@ enum fscache_access_trace { EM(fscache_cookie_new_acquire, "NEW acq ") \ EM(fscache_cookie_put_hash_collision, "PUT hcoll") \ EM(fscache_cookie_put_lru, "PUT lru ") \ + EM(fscache_cookie_put_object, "PUT obj ") \ EM(fscache_cookie_put_over_queued, "PQ overq") \ EM(fscache_cookie_put_relinquish, "PUT relnq") \ EM(fscache_cookie_put_withdrawn, "PUT wthdn") \