From 1c7c474c31aea6d5cb2fb35f31d9e9e91ae466b1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 3 Nov 2009 16:44:44 +0100 Subject: [PATCH] make generic_acl slightly more generic Now that we cache the ACL pointers in the generic inode all the generic_acl cruft can go away and generic_acl.c can directly implement xattr handlers dealing with the full Posix ACL semantics for in-memory filesystems. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- fs/generic_acl.c | 158 ++++++++++++++++++++---------------- include/linux/generic_acl.h | 41 +++------- include/linux/shmem_fs.h | 16 ---- mm/Makefile | 1 - mm/shmem.c | 17 ++-- mm/shmem_acl.c | 133 ------------------------------ 6 files changed, 109 insertions(+), 257 deletions(-) delete mode 100644 mm/shmem_acl.c diff --git a/fs/generic_acl.c b/fs/generic_acl.c index e0b53aa7bbec..55458031e501 100644 --- a/fs/generic_acl.c +++ b/fs/generic_acl.c @@ -1,62 +1,58 @@ /* - * fs/generic_acl.c - * * (C) 2005 Andreas Gruenbacher * * This file is released under the GPL. + * + * Generic ACL support for in-memory filesystems. */ #include #include #include +#include +#include -/** - * generic_acl_list - Generic xattr_handler->list() operation - * @ops: Filesystem specific getacl and setacl callbacks - */ -size_t -generic_acl_list(struct inode *inode, struct generic_acl_operations *ops, - int type, char *list, size_t list_size) + +static size_t +generic_acl_list(struct dentry *dentry, char *list, size_t list_size, + const char *name, size_t name_len, int type) { struct posix_acl *acl; - const char *name; + const char *xname; size_t size; - acl = ops->getacl(inode, type); + acl = get_cached_acl(dentry->d_inode, type); if (!acl) return 0; posix_acl_release(acl); - switch(type) { - case ACL_TYPE_ACCESS: - name = POSIX_ACL_XATTR_ACCESS; - break; - - case ACL_TYPE_DEFAULT: - name = POSIX_ACL_XATTR_DEFAULT; - break; - - default: - return 0; + switch (type) { + case ACL_TYPE_ACCESS: + xname = POSIX_ACL_XATTR_ACCESS; + break; + case ACL_TYPE_DEFAULT: + xname = POSIX_ACL_XATTR_DEFAULT; + break; + default: + return 0; } - size = strlen(name) + 1; + size = strlen(xname) + 1; if (list && size <= list_size) - memcpy(list, name, size); + memcpy(list, xname, size); return size; } -/** - * generic_acl_get - Generic xattr_handler->get() operation - * @ops: Filesystem specific getacl and setacl callbacks - */ -int -generic_acl_get(struct inode *inode, struct generic_acl_operations *ops, - int type, void *buffer, size_t size) +static int +generic_acl_get(struct dentry *dentry, const char *name, void *buffer, + size_t size, int type) { struct posix_acl *acl; int error; - acl = ops->getacl(inode, type); + if (strcmp(name, "") != 0) + return -EINVAL; + + acl = get_cached_acl(dentry->d_inode, type); if (!acl) return -ENODATA; error = posix_acl_to_xattr(acl, buffer, size); @@ -65,17 +61,16 @@ generic_acl_get(struct inode *inode, struct generic_acl_operations *ops, return error; } -/** - * generic_acl_set - Generic xattr_handler->set() operation - * @ops: Filesystem specific getacl and setacl callbacks - */ -int -generic_acl_set(struct inode *inode, struct generic_acl_operations *ops, - int type, const void *value, size_t size) +static int +generic_acl_set(struct dentry *dentry, const char *name, const void *value, + size_t size, int flags, int type) { + struct inode *inode = dentry->d_inode; struct posix_acl *acl = NULL; int error; + if (strcmp(name, "") != 0) + return -EINVAL; if (S_ISLNK(inode->i_mode)) return -EOPNOTSUPP; if (!is_owner_or_cap(inode)) @@ -91,28 +86,27 @@ generic_acl_set(struct inode *inode, struct generic_acl_operations *ops, error = posix_acl_valid(acl); if (error) goto failed; - switch(type) { - case ACL_TYPE_ACCESS: - mode = inode->i_mode; - error = posix_acl_equiv_mode(acl, &mode); - if (error < 0) - goto failed; - inode->i_mode = mode; - if (error == 0) { - posix_acl_release(acl); - acl = NULL; - } - break; - - case ACL_TYPE_DEFAULT: - if (!S_ISDIR(inode->i_mode)) { - error = -EINVAL; - goto failed; - } - break; + switch (type) { + case ACL_TYPE_ACCESS: + mode = inode->i_mode; + error = posix_acl_equiv_mode(acl, &mode); + if (error < 0) + goto failed; + inode->i_mode = mode; + if (error == 0) { + posix_acl_release(acl); + acl = NULL; + } + break; + case ACL_TYPE_DEFAULT: + if (!S_ISDIR(inode->i_mode)) { + error = -EINVAL; + goto failed; + } + break; } } - ops->setacl(inode, type, acl); + set_cached_acl(inode, type, acl); error = 0; failed: posix_acl_release(acl); @@ -121,14 +115,12 @@ failed: /** * generic_acl_init - Take care of acl inheritance at @inode create time - * @ops: Filesystem specific getacl and setacl callbacks * * Files created inside a directory with a default ACL inherit the * directory's default ACL. */ int -generic_acl_init(struct inode *inode, struct inode *dir, - struct generic_acl_operations *ops) +generic_acl_init(struct inode *inode, struct inode *dir) { struct posix_acl *acl = NULL; mode_t mode = inode->i_mode; @@ -136,7 +128,7 @@ generic_acl_init(struct inode *inode, struct inode *dir, inode->i_mode = mode & ~current_umask(); if (!S_ISLNK(inode->i_mode)) - acl = ops->getacl(dir, ACL_TYPE_DEFAULT); + acl = get_cached_acl(dir, ACL_TYPE_DEFAULT); if (acl) { struct posix_acl *clone; @@ -145,7 +137,7 @@ generic_acl_init(struct inode *inode, struct inode *dir, error = -ENOMEM; if (!clone) goto cleanup; - ops->setacl(inode, ACL_TYPE_DEFAULT, clone); + set_cached_acl(inode, ACL_TYPE_DEFAULT, clone); posix_acl_release(clone); } clone = posix_acl_clone(acl, GFP_KERNEL); @@ -156,7 +148,7 @@ generic_acl_init(struct inode *inode, struct inode *dir, if (error >= 0) { inode->i_mode = mode; if (error > 0) - ops->setacl(inode, ACL_TYPE_ACCESS, clone); + set_cached_acl(inode, ACL_TYPE_ACCESS, clone); } posix_acl_release(clone); } @@ -169,20 +161,19 @@ cleanup: /** * generic_acl_chmod - change the access acl of @inode upon chmod() - * @ops: FIlesystem specific getacl and setacl callbacks * * A chmod also changes the permissions of the owner, group/mask, and * other ACL entries. */ int -generic_acl_chmod(struct inode *inode, struct generic_acl_operations *ops) +generic_acl_chmod(struct inode *inode) { struct posix_acl *acl, *clone; int error = 0; if (S_ISLNK(inode->i_mode)) return -EOPNOTSUPP; - acl = ops->getacl(inode, ACL_TYPE_ACCESS); + acl = get_cached_acl(inode, ACL_TYPE_ACCESS); if (acl) { clone = posix_acl_clone(acl, GFP_KERNEL); posix_acl_release(acl); @@ -190,8 +181,37 @@ generic_acl_chmod(struct inode *inode, struct generic_acl_operations *ops) return -ENOMEM; error = posix_acl_chmod_masq(clone, inode->i_mode); if (!error) - ops->setacl(inode, ACL_TYPE_ACCESS, clone); + set_cached_acl(inode, ACL_TYPE_ACCESS, clone); posix_acl_release(clone); } return error; } + +int +generic_check_acl(struct inode *inode, int mask) +{ + struct posix_acl *acl = get_cached_acl(inode, ACL_TYPE_ACCESS); + + if (acl) { + int error = posix_acl_permission(inode, acl, mask); + posix_acl_release(acl); + return error; + } + return -EAGAIN; +} + +struct xattr_handler generic_acl_access_handler = { + .prefix = POSIX_ACL_XATTR_ACCESS, + .flags = ACL_TYPE_ACCESS, + .list = generic_acl_list, + .get = generic_acl_get, + .set = generic_acl_set, +}; + +struct xattr_handler generic_acl_default_handler = { + .prefix = POSIX_ACL_XATTR_DEFAULT, + .flags = ACL_TYPE_DEFAULT, + .list = generic_acl_list, + .get = generic_acl_get, + .set = generic_acl_set, +}; diff --git a/include/linux/generic_acl.h b/include/linux/generic_acl.h index 886f5faa08cb..ca666d18ed67 100644 --- a/include/linux/generic_acl.h +++ b/include/linux/generic_acl.h @@ -1,36 +1,15 @@ -/* - * include/linux/generic_acl.h - * - * (C) 2005 Andreas Gruenbacher - * - * This file is released under the GPL. - */ +#ifndef LINUX_GENERIC_ACL_H +#define LINUX_GENERIC_ACL_H -#ifndef GENERIC_ACL_H -#define GENERIC_ACL_H +#include -#include -#include +struct inode; -/** - * struct generic_acl_operations - filesystem operations - * - * Filesystems must make these operations available to the generic - * operations. - */ -struct generic_acl_operations { - struct posix_acl *(*getacl)(struct inode *, int); - void (*setacl)(struct inode *, int, struct posix_acl *); -}; +extern struct xattr_handler generic_acl_access_handler; +extern struct xattr_handler generic_acl_default_handler; -size_t generic_acl_list(struct inode *, struct generic_acl_operations *, int, - char *, size_t); -int generic_acl_get(struct inode *, struct generic_acl_operations *, int, - void *, size_t); -int generic_acl_set(struct inode *, struct generic_acl_operations *, int, - const void *, size_t); -int generic_acl_init(struct inode *, struct inode *, - struct generic_acl_operations *); -int generic_acl_chmod(struct inode *, struct generic_acl_operations *); +int generic_acl_init(struct inode *, struct inode *); +int generic_acl_chmod(struct inode *); +int generic_check_acl(struct inode *inode, int mask); -#endif +#endif /* LINUX_GENERIC_ACL_H */ diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index deee7afd8d66..e164291fb3e7 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -41,20 +41,4 @@ static inline struct shmem_inode_info *SHMEM_I(struct inode *inode) extern int init_tmpfs(void); extern int shmem_fill_super(struct super_block *sb, void *data, int silent); -#ifdef CONFIG_TMPFS_POSIX_ACL -int shmem_check_acl(struct inode *, int); -int shmem_acl_init(struct inode *, struct inode *); - -extern struct xattr_handler shmem_xattr_acl_access_handler; -extern struct xattr_handler shmem_xattr_acl_default_handler; - -extern struct generic_acl_operations shmem_acl_ops; - -#else -static inline int shmem_acl_init(struct inode *inode, struct inode *dir) -{ - return 0; -} -#endif /* CONFIG_TMPFS_POSIX_ACL */ - #endif diff --git a/mm/Makefile b/mm/Makefile index 82131d0f8d85..7a68d2ab5560 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -22,7 +22,6 @@ obj-$(CONFIG_HUGETLBFS) += hugetlb.o obj-$(CONFIG_NUMA) += mempolicy.o obj-$(CONFIG_SPARSEMEM) += sparse.o obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o -obj-$(CONFIG_TMPFS_POSIX_ACL) += shmem_acl.o obj-$(CONFIG_SLOB) += slob.o obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o obj-$(CONFIG_KSM) += ksm.o diff --git a/mm/shmem.c b/mm/shmem.c index 3cd32c2ea0a0..f8485062f3ba 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -41,6 +41,7 @@ static struct vfsmount *shm_mnt; #include #include +#include #include #include #include @@ -809,7 +810,7 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr) error = inode_setattr(inode, attr); #ifdef CONFIG_TMPFS_POSIX_ACL if (!error && (attr->ia_valid & ATTR_MODE)) - error = generic_acl_chmod(inode, &shmem_acl_ops); + error = generic_acl_chmod(inode); #endif if (page) page_cache_release(page); @@ -1823,11 +1824,13 @@ shmem_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) return error; } } - error = shmem_acl_init(inode, dir); +#ifdef CONFIG_TMPFS_POSIX_ACL + error = generic_acl_init(inode, dir); if (error) { iput(inode); return error; } +#endif if (dir->i_mode & S_ISGID) { inode->i_gid = dir->i_gid; if (S_ISDIR(mode)) @@ -2074,8 +2077,8 @@ static struct xattr_handler shmem_xattr_security_handler = { }; static struct xattr_handler *shmem_xattr_handlers[] = { - &shmem_xattr_acl_access_handler, - &shmem_xattr_acl_default_handler, + &generic_acl_access_handler, + &generic_acl_default_handler, &shmem_xattr_security_handler, NULL }; @@ -2454,7 +2457,7 @@ static const struct inode_operations shmem_inode_operations = { .getxattr = generic_getxattr, .listxattr = generic_listxattr, .removexattr = generic_removexattr, - .check_acl = shmem_check_acl, + .check_acl = generic_check_acl, #endif }; @@ -2477,7 +2480,7 @@ static const struct inode_operations shmem_dir_inode_operations = { .getxattr = generic_getxattr, .listxattr = generic_listxattr, .removexattr = generic_removexattr, - .check_acl = shmem_check_acl, + .check_acl = generic_check_acl, #endif }; @@ -2488,7 +2491,7 @@ static const struct inode_operations shmem_special_inode_operations = { .getxattr = generic_getxattr, .listxattr = generic_listxattr, .removexattr = generic_removexattr, - .check_acl = shmem_check_acl, + .check_acl = generic_check_acl, #endif }; diff --git a/mm/shmem_acl.c b/mm/shmem_acl.c deleted file mode 100644 index f8d5330ec0d7..000000000000 --- a/mm/shmem_acl.c +++ /dev/null @@ -1,133 +0,0 @@ -/* - * mm/shmem_acl.c - * - * (C) 2005 Andreas Gruenbacher - * - * This file is released under the GPL. - */ - -#include -#include -#include -#include - -/** - * shmem_get_acl - generic_acl_operations->getacl() operation - */ -static struct posix_acl * -shmem_get_acl(struct inode *inode, int type) -{ - struct posix_acl *acl = NULL; - - spin_lock(&inode->i_lock); - switch(type) { - case ACL_TYPE_ACCESS: - acl = posix_acl_dup(inode->i_acl); - break; - - case ACL_TYPE_DEFAULT: - acl = posix_acl_dup(inode->i_default_acl); - break; - } - spin_unlock(&inode->i_lock); - - return acl; -} - -/** - * shmem_set_acl - generic_acl_operations->setacl() operation - */ -static void -shmem_set_acl(struct inode *inode, int type, struct posix_acl *acl) -{ - struct posix_acl *free = NULL; - - spin_lock(&inode->i_lock); - switch(type) { - case ACL_TYPE_ACCESS: - free = inode->i_acl; - inode->i_acl = posix_acl_dup(acl); - break; - - case ACL_TYPE_DEFAULT: - free = inode->i_default_acl; - inode->i_default_acl = posix_acl_dup(acl); - break; - } - spin_unlock(&inode->i_lock); - posix_acl_release(free); -} - -struct generic_acl_operations shmem_acl_ops = { - .getacl = shmem_get_acl, - .setacl = shmem_set_acl, -}; - -static size_t -shmem_xattr_list_acl(struct dentry *dentry, char *list, size_t list_size, - const char *name, size_t name_len, int type) -{ - return generic_acl_list(dentry->d_inode, &shmem_acl_ops, - type, list, list_size); -} - -static int -shmem_xattr_get_acl(struct dentry *dentry, const char *name, void *buffer, - size_t size, int type) -{ - if (strcmp(name, "") != 0) - return -EINVAL; - return generic_acl_get(dentry->d_inode, &shmem_acl_ops, type, - buffer, size); -} - -static int -shmem_xattr_set_acl(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags, int type) -{ - if (strcmp(name, "") != 0) - return -EINVAL; - return generic_acl_set(dentry->d_inode, &shmem_acl_ops, type, - value, size); -} - -struct xattr_handler shmem_xattr_acl_access_handler = { - .prefix = POSIX_ACL_XATTR_ACCESS, - .flags = ACL_TYPE_ACCESS, - .list = shmem_xattr_list_acl, - .get = shmem_xattr_get_acl, - .set = shmem_xattr_set_acl, -}; - -struct xattr_handler shmem_xattr_acl_default_handler = { - .prefix = POSIX_ACL_XATTR_DEFAULT, - .flags = ACL_TYPE_DEFAULT, - .list = shmem_xattr_list_acl, - .get = shmem_xattr_get_acl, - .set = shmem_xattr_set_acl, -}; - -/** - * shmem_acl_init - Inizialize the acl(s) of a new inode - */ -int -shmem_acl_init(struct inode *inode, struct inode *dir) -{ - return generic_acl_init(inode, dir, &shmem_acl_ops); -} - -/** - * shmem_check_acl - check_acl() callback for generic_permission() - */ -int -shmem_check_acl(struct inode *inode, int mask) -{ - struct posix_acl *acl = shmem_get_acl(inode, ACL_TYPE_ACCESS); - - if (acl) { - int error = posix_acl_permission(inode, acl, mask); - posix_acl_release(acl); - return error; - } - return -EAGAIN; -} -- 2.20.1