Return-Path: Received: from mail-wi0-f182.google.com ([209.85.212.182]:33624 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932190AbbDXLFO (ORCPT ); Fri, 24 Apr 2015 07:05:14 -0400 From: Andreas Gruenbacher To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org Subject: [RFC v3 16/45] vfs: Cache richacl in struct inode Date: Fri, 24 Apr 2015 13:04:13 +0200 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: linux-nfs-owner@vger.kernel.org List-ID: Cache richacls in struct inode so that this doesn't have to be done individually in each filesystem. This is similar to POSIX ACLs. Signed-off-by: Andreas Gruenbacher --- fs/inode.c | 11 ++++++-- fs/posix_acl.c | 2 +- fs/richacl_base.c | 8 ++++-- fs/richacl_inode.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 6 +++- include/linux/richacl.h | 15 ++++++---- 6 files changed, 102 insertions(+), 13 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index 555fe9c..5272412 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -175,8 +175,11 @@ int inode_init_always(struct super_block *sb, struct inode *inode) inode->i_private = NULL; inode->i_mapping = mapping; INIT_HLIST_HEAD(&inode->i_dentry); /* buggered by rcu freeing */ -#ifdef CONFIG_FS_POSIX_ACL - inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED; +#if defined(CONFIG_FS_POSIX_ACL) || defined(CONFIG_FS_RICHACL) + inode->i_acl = ACL_NOT_CACHED; +# if defined(CONFIG_FS_POSIX_ACL) + inode->i_default_acl = ACL_NOT_CACHED; +# endif #endif #ifdef CONFIG_FSNOTIFY @@ -231,11 +234,13 @@ void __destroy_inode(struct inode *inode) atomic_long_dec(&inode->i_sb->s_remove_count); } -#ifdef CONFIG_FS_POSIX_ACL +#if defined(CONFIG_FS_POSIX_ACL) || defined(CONFIG_FS_RICHACL) if (inode->i_acl && inode->i_acl != ACL_NOT_CACHED) put_base_acl(inode->i_acl); +# if defined(CONFIG_FS_POSIX_ACL) if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED) put_base_acl(inode->i_default_acl); +# endif #endif this_cpu_dec(nr_inodes); } diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 2fbfec8..ebf96b2 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -38,7 +38,7 @@ struct posix_acl *get_cached_acl(struct inode *inode, int type) { struct posix_acl **p = acl_by_type(inode, type); struct posix_acl *acl = ACCESS_ONCE(*p); - if (acl) { + if (acl && IS_POSIXACL(inode)) { spin_lock(&inode->i_lock); acl = *p; if (acl != ACL_NOT_CACHED) diff --git a/fs/richacl_base.c b/fs/richacl_base.c index 261ddd2..5273ccb 100644 --- a/fs/richacl_base.c +++ b/fs/richacl_base.c @@ -29,11 +29,13 @@ MODULE_LICENSE("GPL"); struct richacl * richacl_alloc(int count, gfp_t gfp) { - size_t size = sizeof(struct richacl) + count * sizeof(struct richace); + size_t size = max(sizeof(struct rcu_head), + sizeof(struct richacl) + + count * sizeof(struct richace)); struct richacl *acl = kzalloc(size, gfp); if (acl) { - atomic_set(&acl->a_refcount, 1); + atomic_set(&acl->a_base.ba_refcount, 1); acl->a_count = count; } return acl; @@ -52,7 +54,7 @@ richacl_clone(const struct richacl *acl, gfp_t gfp) if (dup) { memcpy(dup, acl, size); - atomic_set(&dup->a_refcount, 1); + atomic_set(&dup->a_base.ba_refcount, 1); } return dup; } diff --git a/fs/richacl_inode.c b/fs/richacl_inode.c index 33e591a..b421f68 100644 --- a/fs/richacl_inode.c +++ b/fs/richacl_inode.c @@ -20,6 +20,79 @@ #include #include +struct richacl *get_cached_richacl(struct inode *inode) +{ + struct richacl *acl; + + acl = (struct richacl *)ACCESS_ONCE(inode->i_acl); + if (acl && IS_RICHACL(inode)) { + spin_lock(&inode->i_lock); + acl = (struct richacl *)inode->i_acl; + if (acl != ACL_NOT_CACHED) + acl = richacl_get(acl); + spin_unlock(&inode->i_lock); + } + return acl; +} +EXPORT_SYMBOL_GPL(get_cached_richacl); + +struct richacl *get_cached_richacl_rcu(struct inode *inode) +{ + return (struct richacl *)rcu_dereference(inode->i_acl); +} +EXPORT_SYMBOL_GPL(get_cached_richacl_rcu); + +void set_cached_richacl(struct inode *inode, struct richacl *acl) +{ + struct base_acl *old = NULL; + spin_lock(&inode->i_lock); + old = inode->i_acl; + rcu_assign_pointer(inode->i_acl, &richacl_get(acl)->a_base); + spin_unlock(&inode->i_lock); + if (old != ACL_NOT_CACHED) + put_base_acl(old); +} +EXPORT_SYMBOL_GPL(set_cached_richacl); + +void forget_cached_richacl(struct inode *inode) +{ + struct base_acl *old = NULL; + spin_lock(&inode->i_lock); + old = inode->i_acl; + inode->i_acl = ACL_NOT_CACHED; + spin_unlock(&inode->i_lock); + if (old != ACL_NOT_CACHED) + put_base_acl(old); +} +EXPORT_SYMBOL_GPL(forget_cached_richacl); + +struct richacl *get_richacl(struct inode *inode) +{ + struct richacl *acl; + + acl = get_cached_richacl(inode); + if (acl != ACL_NOT_CACHED) + return acl; + + if (!IS_RICHACL(inode)) + return NULL; + + /* + * A filesystem can force a ACL callback by just never filling the + * ACL cache. But normally you'd fill the cache either at inode + * instantiation time, or on the first ->get_richacl call. + * + * If the filesystem doesn't have a get_richacl() function at all, + * we'll just create the negative cache entry. + */ + if (!inode->i_op->get_richacl) { + set_cached_richacl(inode, NULL); + return NULL; + } + return inode->i_op->get_richacl(inode); +} +EXPORT_SYMBOL_GPL(get_richacl); + /** * richacl_permission - richacl permission check algorithm * @inode: inode to check diff --git a/include/linux/fs.h b/include/linux/fs.h index 6e0da10..7584a63 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -551,6 +551,7 @@ struct base_acl { atomic_t ba_refcount; }; struct posix_acl; +struct richacl; #define ACL_NOT_CACHED ((void *)(-1)) #define IOP_FASTPERM 0x0001 @@ -569,9 +570,11 @@ struct inode { kgid_t i_gid; unsigned int i_flags; -#if defined(CONFIG_FS_POSIX_ACL) +#if defined(CONFIG_FS_POSIX_ACL) || defined(CONFIG_FS_RICHACL) struct base_acl *i_acl; +# if defined(CONFIG_FS_POSIX_ACL) struct base_acl *i_default_acl; +# endif #endif const struct inode_operations *i_op; @@ -1587,6 +1590,7 @@ struct inode_operations { void * (*follow_link) (struct dentry *, struct nameidata *); int (*permission) (struct inode *, int); struct posix_acl * (*get_acl)(struct inode *, int); + struct richacl * (*get_richacl)(struct inode *); int (*readlink) (struct dentry *, char __user *,int); void (*put_link) (struct dentry *, struct nameidata *, void *); diff --git a/include/linux/richacl.h b/include/linux/richacl.h index 5eb198d..6d88ee9 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -33,7 +33,7 @@ struct richace { }; struct richacl { - atomic_t a_refcount; + struct base_acl a_base; unsigned int a_owner_mask; unsigned int a_group_mask; unsigned int a_other_mask; @@ -167,8 +167,7 @@ struct richacl { static inline struct richacl * richacl_get(struct richacl *acl) { - if (acl) - atomic_inc(&acl->a_base.ba_refcount); + get_base_acl(&acl->a_base); return acl; } @@ -178,10 +177,16 @@ richacl_get(struct richacl *acl) static inline void richacl_put(struct richacl *acl) { - if (acl && atomic_dec_and_test(&acl->a_refcount)) - kfree(acl); + BUILD_BUG_ON(offsetof(struct richacl, a_base) != 0); + put_base_acl(&acl->a_base); } +extern struct richacl *get_cached_richacl(struct inode *); +extern struct richacl *get_cached_richacl_rcu(struct inode *); +extern void set_cached_richacl(struct inode *, struct richacl *); +extern void forget_cached_richacl(struct inode *); +extern struct richacl *get_richacl(struct inode *); + /** * richace_is_owner - check if @ace is an OWNER@ entry */ -- 2.1.0