From: Andreas Gruenbacher Subject: [PATCH v11 10/48] vfs: Cache base_acl objects in inodes Date: Fri, 16 Oct 2015 17:17:48 +0200 Message-ID: <1445008706-15115-11-git-send-email-agruenba@redhat.com> References: <1445008706-15115-1-git-send-email-agruenba@redhat.com> To: Alexander Viro , "Theodore Ts'o" , Andreas Dilger , "J. Bruce Fields" , Jeff Layton , Trond Myklebust , Anna Schumaker , Dave Chinner , linux-ext4@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-api@vger.kernel.org Return-path: In-Reply-To: <1445008706-15115-1-git-send-email-agruenba@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org 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/jffs2/acl.c | 6 ++++-- fs/posix_acl.c | 18 +++++++++--------- include/linux/fs.h | 25 ++++++++++++++++++++++--- include/linux/posix_acl.h | 12 ++++-------- include/linux/richacl.h | 2 +- 8 files changed, 45 insertions(+), 28 deletions(-) diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c index b4ed6c8..5766f69 100644 --- a/drivers/staging/lustre/lustre/llite/llite_lib.c +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c @@ -1118,7 +1118,7 @@ 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 c8f25f7..a4207de 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 78a17b8..2a387f4 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/jffs2/acl.c b/fs/jffs2/acl.c index 2f7a3c0..04a5836 100644 --- a/fs/jffs2/acl.c +++ b/fs/jffs2/acl.c @@ -294,13 +294,15 @@ int jffs2_init_acl_post(struct inode *inode) int rc; if (inode->i_default_acl) { - rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_DEFAULT, inode->i_default_acl); + rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_DEFAULT, + *acl_by_type(inode, ACL_TYPE_DEFAULT)); if (rc) return rc; } if (inode->i_acl) { - rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_ACCESS, inode->i_acl); + rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_ACCESS, + *acl_by_type(inode, ACL_TYPE_ACCESS)); if (rc) return rc; } diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 4fb17de..b3b2265 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); @@ -162,7 +162,7 @@ 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; } @@ -384,7 +384,7 @@ 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) { @@ -439,7 +439,7 @@ 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 ba91a89..3c22c92 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -576,6 +576,12 @@ static inline void mapping_allow_writable(struct address_space *mapping) #define i_size_ordered_init(inode) do { } while (0) #endif +struct base_acl { + union { + atomic_t ba_refcount; + struct rcu_head ba_rcu; + }; +}; struct posix_acl; #define ACL_NOT_CACHED ((void *)(-1)) @@ -595,9 +601,9 @@ 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; @@ -3059,4 +3065,17 @@ static inline bool dir_relax(struct inode *inode) extern bool path_noexec(const struct path *path); +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(acl, ba_rcu); +} + #endif /* _LINUX_FS_H */ diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h index 3e96a6a..2c46441 100644 --- a/include/linux/posix_acl.h +++ b/include/linux/posix_acl.h @@ -43,10 +43,7 @@ struct posix_acl_entry { }; struct posix_acl { - union { - atomic_t a_refcount; - struct rcu_head a_rcu; - }; + struct base_acl a_base; unsigned int a_count; struct posix_acl_entry a_entries[0]; }; @@ -61,8 +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; } @@ -72,8 +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(acl, a_rcu); + 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 d5fa7b9..575ec32 100644 --- a/include/linux/richacl.h +++ b/include/linux/richacl.h @@ -94,7 +94,7 @@ 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; } -- 2.5.0