Return-Path: Received: from mail-wg0-f53.google.com ([74.125.82.53]:35495 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932142AbbDXLFM (ORCPT ); Fri, 24 Apr 2015 07:05:12 -0400 From: Andreas Gruenbacher To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org Subject: [RFC v3 15/45] vfs: Cache base_acl objects in inodes Date: Fri, 24 Apr 2015 13:04:12 +0200 Message-Id: <5f8cccbd368c1bd65bd2cf5f4f62863dd4ec1d9c.1429868795.git.agruenba@redhat.com> In-Reply-To: References: In-Reply-To: References: Sender: linux-nfs-owner@vger.kernel.org List-ID: POSIX ACLs and richacls are both objects allocated by kmalloc() with a reference count which are freed by kfree_rcu(). An inode can either cache an access and a default POSIX ACL, or a richacl. (Richacls do not have default acls). To allow an inode to cache either of the two kinds of acls, introduce a new base_acl type and convert i_acl and i_default_acl to that type. In most cases, the vfs then doesn't have to care which kind of acl an inode caches (if any). Signed-off-by: Andreas Gruenbacher --- drivers/staging/lustre/lustre/llite/llite_lib.c | 2 +- fs/f2fs/acl.c | 4 ++-- fs/inode.c | 4 ++-- fs/posix_acl.c | 18 +++++++++--------- include/linux/fs.h | 22 +++++++++++++++++++--- include/linux/posix_acl.h | 9 ++++----- include/linux/richacl.h | 2 +- 7 files changed, 38 insertions(+), 23 deletions(-) diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c index 0c1b583..c8cae33 100644 --- a/drivers/staging/lustre/lustre/llite/llite_lib.c +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c @@ -1145,7 +1145,7 @@ void ll_clear_inode(struct inode *inode) } #ifdef CONFIG_FS_POSIX_ACL else if (lli->lli_posix_acl) { - LASSERT(atomic_read(&lli->lli_posix_acl->a_refcount) == 1); + LASSERT(atomic_read(&lli->lli_posix_acl->a_base.ba_refcount) == 1); LASSERT(lli->lli_remote_perms == NULL); posix_acl_release(lli->lli_posix_acl); lli->lli_posix_acl = NULL; diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c index 7422027..ccb2c7c 100644 --- a/fs/f2fs/acl.c +++ b/fs/f2fs/acl.c @@ -270,7 +270,7 @@ static struct posix_acl *f2fs_acl_clone(const struct posix_acl *acl, sizeof(struct posix_acl_entry); clone = kmemdup(acl, size, flags); if (clone) - atomic_set(&clone->a_refcount, 1); + atomic_set(&clone->a_base.ba_refcount, 1); } return clone; } @@ -282,7 +282,7 @@ static int f2fs_acl_create_masq(struct posix_acl *acl, umode_t *mode_p) umode_t mode = *mode_p; int not_equiv = 0; - /* assert(atomic_read(acl->a_refcount) == 1); */ + /* assert(atomic_read(acl->a_base.ba_refcount) == 1); */ FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { diff --git a/fs/inode.c b/fs/inode.c index f00b16f..555fe9c 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -233,9 +233,9 @@ void __destroy_inode(struct inode *inode) #ifdef CONFIG_FS_POSIX_ACL if (inode->i_acl && inode->i_acl != ACL_NOT_CACHED) - posix_acl_release(inode->i_acl); + put_base_acl(inode->i_acl); if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED) - posix_acl_release(inode->i_default_acl); + put_base_acl(inode->i_default_acl); #endif this_cpu_dec(nr_inodes); } diff --git a/fs/posix_acl.c b/fs/posix_acl.c index efe983e..2fbfec8 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -25,9 +25,9 @@ struct posix_acl **acl_by_type(struct inode *inode, int type) { switch (type) { case ACL_TYPE_ACCESS: - return &inode->i_acl; + return (struct posix_acl **)&inode->i_acl; case ACL_TYPE_DEFAULT: - return &inode->i_default_acl; + return (struct posix_acl **)&inode->i_default_acl; default: BUG(); } @@ -83,16 +83,16 @@ EXPORT_SYMBOL(forget_cached_acl); void forget_all_cached_acls(struct inode *inode) { - struct posix_acl *old_access, *old_default; + struct base_acl *old_access, *old_default; spin_lock(&inode->i_lock); old_access = inode->i_acl; old_default = inode->i_default_acl; inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED; spin_unlock(&inode->i_lock); if (old_access != ACL_NOT_CACHED) - posix_acl_release(old_access); + put_base_acl(old_access); if (old_default != ACL_NOT_CACHED) - posix_acl_release(old_default); + put_base_acl(old_default); } EXPORT_SYMBOL(forget_all_cached_acls); @@ -129,7 +129,7 @@ EXPORT_SYMBOL(get_acl); void posix_acl_init(struct posix_acl *acl, int count) { - atomic_set(&acl->a_refcount, 1); + atomic_set(&acl->a_base.ba_refcount, 1); acl->a_count = count; } EXPORT_SYMBOL(posix_acl_init); @@ -163,7 +163,7 @@ posix_acl_clone(const struct posix_acl *acl, gfp_t flags) sizeof(struct posix_acl_entry); clone = kmemdup(acl, size, flags); if (clone) - atomic_set(&clone->a_refcount, 1); + atomic_set(&clone->a_base.ba_refcount, 1); } return clone; } @@ -385,7 +385,7 @@ static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p) umode_t mode = *mode_p; int not_equiv = 0; - /* assert(atomic_read(acl->a_refcount) == 1); */ + /* assert(atomic_read(acl->a_base.ba_refcount) == 1); */ FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { @@ -440,7 +440,7 @@ static int __posix_acl_chmod_masq(struct posix_acl *acl, umode_t mode) struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL; struct posix_acl_entry *pa, *pe; - /* assert(atomic_read(acl->a_refcount) == 1); */ + /* assert(atomic_read(acl->a_base.ba_refcount) == 1); */ FOREACH_ACL_ENTRY(pa, acl, pe) { switch(pa->e_tag) { diff --git a/include/linux/fs.h b/include/linux/fs.h index 0121047..6e0da10 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -547,6 +547,9 @@ static inline void mapping_allow_writable(struct address_space *mapping) #define i_size_ordered_init(inode) do { } while (0) #endif +struct base_acl { + atomic_t ba_refcount; +}; struct posix_acl; #define ACL_NOT_CACHED ((void *)(-1)) @@ -566,9 +569,9 @@ struct inode { kgid_t i_gid; unsigned int i_flags; -#ifdef CONFIG_FS_POSIX_ACL - struct posix_acl *i_acl; - struct posix_acl *i_default_acl; +#if defined(CONFIG_FS_POSIX_ACL) + struct base_acl *i_acl; + struct base_acl *i_default_acl; #endif const struct inode_operations *i_op; @@ -2937,4 +2940,17 @@ static inline bool dir_relax(struct inode *inode) return !IS_DEADDIR(inode); } +static inline struct base_acl *get_base_acl(struct base_acl *acl) +{ + if (acl) + atomic_inc(&acl->ba_refcount); + return acl; +} + +static inline void put_base_acl(struct base_acl *acl) +{ + if (acl && atomic_dec_and_test(&acl->ba_refcount)) + __kfree_rcu((struct rcu_head *)acl, 0); +} + #endif /* _LINUX_FS_H */ diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h index 66cf477..2c46441 100644 --- a/include/linux/posix_acl.h +++ b/include/linux/posix_acl.h @@ -43,7 +43,7 @@ struct posix_acl_entry { }; struct posix_acl { - atomic_t a_refcount; + struct base_acl a_base; unsigned int a_count; struct posix_acl_entry a_entries[0]; }; @@ -58,8 +58,7 @@ struct posix_acl { static inline struct posix_acl * posix_acl_dup(struct posix_acl *acl) { - if (acl) - atomic_inc(&acl->a_refcount); + get_base_acl(&acl->a_base); return acl; } @@ -69,8 +68,8 @@ posix_acl_dup(struct posix_acl *acl) static inline void posix_acl_release(struct posix_acl *acl) { - if (acl && atomic_dec_and_test(&acl->a_refcount)) - __kfree_rcu((struct rcu_head *)acl, 0); + BUILD_BUG_ON(offsetof(struct posix_acl, a_base) != 0); + put_base_acl(&acl->a_base); } diff --git a/include/linux/richacl.h b/include/linux/richacl.h index d11e8f3..5eb198d 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -168,7 +168,7 @@ static inline struct richacl * richacl_get(struct richacl *acl) { if (acl) - atomic_inc(&acl->a_refcount); + atomic_inc(&acl->a_base.ba_refcount); return acl; } -- 2.1.0