From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:54618 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727728AbeIDUc3 (ORCPT ); Tue, 4 Sep 2018 16:32:29 -0400 From: Jan Kara To: Paul Moore Cc: Al Viro , linux-audit@redhat.com, , rgb@redhat.com, Amir Goldstein , Jan Kara Subject: [PATCH 06/11] audit: Factor out chunk replacement code Date: Tue, 4 Sep 2018 18:06:26 +0200 Message-Id: <20180904160632.21210-7-jack@suse.cz> In-Reply-To: <20180904160632.21210-1-jack@suse.cz> References: <20180904160632.21210-1-jack@suse.cz> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Chunk replacement code is very similar for the cases where we grow or shrink chunk. Factor the code out into a common helper function. Signed-off-by: Jan Kara --- kernel/audit_tree.c | 86 +++++++++++++++++++++++++---------------------------- 1 file changed, 40 insertions(+), 46 deletions(-) diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 307749d6773c..6978a92f6fef 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -235,6 +235,38 @@ static struct audit_chunk *find_chunk(struct node *p) return container_of(p, struct audit_chunk, owners[0]); } +static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old, + struct node *skip) +{ + struct audit_tree *owner; + int i, j; + + new->key = old->key; + list_replace_init(&old->trees, &new->trees); + list_for_each_entry(owner, &new->trees, same_root) + owner->root = new; + for (i = j = 0; j < old->count; i++, j++) { + if (&old->owners[j] == skip) { + i--; + continue; + } + owner = old->owners[j].owner; + new->owners[i].owner = owner; + new->owners[i].index = old->owners[j].index - j + i; + if (!owner) /* result of earlier fallback */ + continue; + get_tree(owner); + list_replace_init(&old->owners[j].list, &new->owners[i].list); + } + /* + * Make sure chunk is fully initialized before making it visible in the + * hash. Pairs with a data dependency barrier in READ_ONCE() in + * audit_tree_lookup(). + */ + smp_wmb(); + list_replace_rcu(&old->hash, &new->hash); +} + static void untag_chunk(struct node *p) { struct audit_chunk *chunk = find_chunk(p); @@ -242,7 +274,6 @@ static void untag_chunk(struct node *p) struct audit_chunk *new = NULL; struct audit_tree *owner; int size = chunk->count - 1; - int i, j; fsnotify_get_mark(entry); @@ -291,38 +322,16 @@ static void untag_chunk(struct node *p) chunk->dead = 1; spin_lock(&hash_lock); - new->key = chunk->key; - list_replace_init(&chunk->trees, &new->trees); if (owner->root == chunk) { list_del_init(&owner->same_root); owner->root = NULL; } - - for (i = j = 0; j <= size; i++, j++) { - struct audit_tree *s; - if (&chunk->owners[j] == p) { - list_del_init(&p->list); - i--; - continue; - } - s = chunk->owners[j].owner; - new->owners[i].owner = s; - new->owners[i].index = chunk->owners[j].index - j + i; - if (!s) /* result of earlier fallback */ - continue; - get_tree(s); - list_replace_init(&chunk->owners[j].list, &new->owners[i].list); - } - - list_for_each_entry(owner, &new->trees, same_root) - owner->root = new; + list_del_init(&p->list); /* - * Make sure chunk is fully initialized before making it visible in the - * hash. Pairs with a data dependency barrier in READ_ONCE() in - * audit_tree_lookup(). + * This has to go last when updating chunk as once replace_chunk() is + * called, new RCU readers can see the new chunk. */ - smp_wmb(); - list_replace_rcu(&chunk->hash, &new->hash); + replace_chunk(new, chunk, p); spin_unlock(&hash_lock); fsnotify_detach_mark(entry); mutex_unlock(&entry->group->mark_mutex); @@ -399,7 +408,6 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree) static int tag_chunk(struct inode *inode, struct audit_tree *tree) { struct fsnotify_mark *old_entry, *chunk_entry; - struct audit_tree *owner; struct audit_chunk *chunk, *old; struct node *p; int n; @@ -464,35 +472,21 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) fsnotify_put_mark(old_entry); return 0; } - chunk->key = old->key; - list_replace_init(&old->trees, &chunk->trees); - for (n = 0, p = chunk->owners; n < old->count; n++, p++) { - struct audit_tree *s = old->owners[n].owner; - p->owner = s; - p->index = old->owners[n].index; - if (!s) /* result of fallback in untag */ - continue; - get_tree(s); - list_replace_init(&old->owners[n].list, &p->list); - } + p = &chunk->owners[chunk->count - 1]; p->index = (chunk->count - 1) | (1U<<31); p->owner = tree; get_tree(tree); list_add(&p->list, &tree->chunks); - list_for_each_entry(owner, &chunk->trees, same_root) - owner->root = chunk; old->dead = 1; if (!tree->root) { tree->root = chunk; list_add(&tree->same_root, &chunk->trees); } /* - * Make sure chunk is fully initialized before making it visible in the - * hash. Pairs with a data dependency barrier in READ_ONCE() in - * audit_tree_lookup(). + * This has to go last when updating chunk as once replace_chunk() is + * called, new RCU readers can see the new chunk. */ - smp_wmb(); - list_replace_rcu(&old->hash, &chunk->hash); + replace_chunk(chunk, old, NULL); spin_unlock(&hash_lock); fsnotify_detach_mark(old_entry); mutex_unlock(&audit_tree_group->mark_mutex); -- 2.16.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: [PATCH 06/11] audit: Factor out chunk replacement code Date: Tue, 4 Sep 2018 18:06:26 +0200 Message-ID: <20180904160632.21210-7-jack@suse.cz> References: <20180904160632.21210-1-jack@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180904160632.21210-1-jack@suse.cz> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-audit-bounces@redhat.com Errors-To: linux-audit-bounces@redhat.com To: Paul Moore Cc: Jan Kara , rgb@redhat.com, Amir Goldstein , linux-audit@redhat.com, Al Viro , linux-fsdevel@vger.kernel.org List-Id: linux-audit@redhat.com Chunk replacement code is very similar for the cases where we grow or shrink chunk. Factor the code out into a common helper function. Signed-off-by: Jan Kara --- kernel/audit_tree.c | 86 +++++++++++++++++++++++++---------------------------- 1 file changed, 40 insertions(+), 46 deletions(-) diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 307749d6773c..6978a92f6fef 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -235,6 +235,38 @@ static struct audit_chunk *find_chunk(struct node *p) return container_of(p, struct audit_chunk, owners[0]); } +static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old, + struct node *skip) +{ + struct audit_tree *owner; + int i, j; + + new->key = old->key; + list_replace_init(&old->trees, &new->trees); + list_for_each_entry(owner, &new->trees, same_root) + owner->root = new; + for (i = j = 0; j < old->count; i++, j++) { + if (&old->owners[j] == skip) { + i--; + continue; + } + owner = old->owners[j].owner; + new->owners[i].owner = owner; + new->owners[i].index = old->owners[j].index - j + i; + if (!owner) /* result of earlier fallback */ + continue; + get_tree(owner); + list_replace_init(&old->owners[j].list, &new->owners[i].list); + } + /* + * Make sure chunk is fully initialized before making it visible in the + * hash. Pairs with a data dependency barrier in READ_ONCE() in + * audit_tree_lookup(). + */ + smp_wmb(); + list_replace_rcu(&old->hash, &new->hash); +} + static void untag_chunk(struct node *p) { struct audit_chunk *chunk = find_chunk(p); @@ -242,7 +274,6 @@ static void untag_chunk(struct node *p) struct audit_chunk *new = NULL; struct audit_tree *owner; int size = chunk->count - 1; - int i, j; fsnotify_get_mark(entry); @@ -291,38 +322,16 @@ static void untag_chunk(struct node *p) chunk->dead = 1; spin_lock(&hash_lock); - new->key = chunk->key; - list_replace_init(&chunk->trees, &new->trees); if (owner->root == chunk) { list_del_init(&owner->same_root); owner->root = NULL; } - - for (i = j = 0; j <= size; i++, j++) { - struct audit_tree *s; - if (&chunk->owners[j] == p) { - list_del_init(&p->list); - i--; - continue; - } - s = chunk->owners[j].owner; - new->owners[i].owner = s; - new->owners[i].index = chunk->owners[j].index - j + i; - if (!s) /* result of earlier fallback */ - continue; - get_tree(s); - list_replace_init(&chunk->owners[j].list, &new->owners[i].list); - } - - list_for_each_entry(owner, &new->trees, same_root) - owner->root = new; + list_del_init(&p->list); /* - * Make sure chunk is fully initialized before making it visible in the - * hash. Pairs with a data dependency barrier in READ_ONCE() in - * audit_tree_lookup(). + * This has to go last when updating chunk as once replace_chunk() is + * called, new RCU readers can see the new chunk. */ - smp_wmb(); - list_replace_rcu(&chunk->hash, &new->hash); + replace_chunk(new, chunk, p); spin_unlock(&hash_lock); fsnotify_detach_mark(entry); mutex_unlock(&entry->group->mark_mutex); @@ -399,7 +408,6 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree) static int tag_chunk(struct inode *inode, struct audit_tree *tree) { struct fsnotify_mark *old_entry, *chunk_entry; - struct audit_tree *owner; struct audit_chunk *chunk, *old; struct node *p; int n; @@ -464,35 +472,21 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) fsnotify_put_mark(old_entry); return 0; } - chunk->key = old->key; - list_replace_init(&old->trees, &chunk->trees); - for (n = 0, p = chunk->owners; n < old->count; n++, p++) { - struct audit_tree *s = old->owners[n].owner; - p->owner = s; - p->index = old->owners[n].index; - if (!s) /* result of fallback in untag */ - continue; - get_tree(s); - list_replace_init(&old->owners[n].list, &p->list); - } + p = &chunk->owners[chunk->count - 1]; p->index = (chunk->count - 1) | (1U<<31); p->owner = tree; get_tree(tree); list_add(&p->list, &tree->chunks); - list_for_each_entry(owner, &chunk->trees, same_root) - owner->root = chunk; old->dead = 1; if (!tree->root) { tree->root = chunk; list_add(&tree->same_root, &chunk->trees); } /* - * Make sure chunk is fully initialized before making it visible in the - * hash. Pairs with a data dependency barrier in READ_ONCE() in - * audit_tree_lookup(). + * This has to go last when updating chunk as once replace_chunk() is + * called, new RCU readers can see the new chunk. */ - smp_wmb(); - list_replace_rcu(&old->hash, &chunk->hash); + replace_chunk(chunk, old, NULL); spin_unlock(&hash_lock); fsnotify_detach_mark(old_entry); mutex_unlock(&audit_tree_group->mark_mutex); -- 2.16.4