diff options
Diffstat (limited to 'fs/sysfs')
| -rw-r--r-- | fs/sysfs/dir.c | 388 | ||||
| -rw-r--r-- | fs/sysfs/file.c | 41 | ||||
| -rw-r--r-- | fs/sysfs/inode.c | 176 | ||||
| -rw-r--r-- | fs/sysfs/symlink.c | 11 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 9 |
5 files changed, 253 insertions, 372 deletions
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index e0201837d24..f05f2303a8b 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -25,7 +25,6 @@ #include "sysfs.h" DEFINE_MUTEX(sysfs_mutex); -DEFINE_MUTEX(sysfs_rename_mutex); DEFINE_SPINLOCK(sysfs_assoc_lock); static DEFINE_SPINLOCK(sysfs_ino_lock); @@ -85,46 +84,6 @@ static void sysfs_unlink_sibling(struct sysfs_dirent *sd) } /** - * sysfs_get_dentry - get dentry for the given sysfs_dirent - * @sd: sysfs_dirent of interest - * - * Get dentry for @sd. Dentry is looked up if currently not - * present. This function descends from the root looking up - * dentry for each step. - * - * LOCKING: - * mutex_lock(sysfs_rename_mutex) - * - * RETURNS: - * Pointer to found dentry on success, ERR_PTR() value on error. - */ -struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd) -{ - struct dentry *dentry = dget(sysfs_sb->s_root); - - while (dentry->d_fsdata != sd) { - struct sysfs_dirent *cur; - struct dentry *parent; - - /* find the first ancestor which hasn't been looked up */ - cur = sd; - while (cur->s_parent != dentry->d_fsdata) - cur = cur->s_parent; - - /* look it up */ - parent = dentry; - mutex_lock(&parent->d_inode->i_mutex); - dentry = lookup_one_noperm(cur->s_name, parent); - mutex_unlock(&parent->d_inode->i_mutex); - dput(parent); - - if (IS_ERR(dentry)) - break; - } - return dentry; -} - -/** * sysfs_get_active - get an active reference to sysfs_dirent * @sd: sysfs_dirent to get an active reference to * @@ -298,7 +257,61 @@ void release_sysfs_dirent(struct sysfs_dirent * sd) goto repeat; } -static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) +static int sysfs_dentry_delete(struct dentry *dentry) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + return !!(sd->s_flags & SYSFS_FLAG_REMOVED); +} + +static int sysfs_dentry_revalidate(struct dentry *dentry, struct nameidata *nd) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + int is_dir; + + mutex_lock(&sysfs_mutex); + + /* The sysfs dirent has been deleted */ + if (sd->s_flags & SYSFS_FLAG_REMOVED) + goto out_bad; + + /* The sysfs dirent has been moved? */ + if (dentry->d_parent->d_fsdata != sd->s_parent) + goto out_bad; + + /* The sysfs dirent has been renamed */ + if (strcmp(dentry->d_name.name, sd->s_name) != 0) + goto out_bad; + + mutex_unlock(&sysfs_mutex); +out_valid: + return 1; +out_bad: + /* Remove the dentry from the dcache hashes. + * If this is a deleted dentry we use d_drop instead of d_delete + * so sysfs doesn't need to cope with negative dentries. + * + * If this is a dentry that has simply been renamed we + * use d_drop to remove it from the dcache lookup on its + * old parent. If this dentry persists later when a lookup + * is performed at its new name the dentry will be readded + * to the dcache hashes. + */ + is_dir = (sysfs_type(sd) == SYSFS_DIR); + mutex_unlock(&sysfs_mutex); + if (is_dir) { + /* If we have submounts we must allow the vfs caches + * to lie about the state of the filesystem to prevent + * leaks and other nasty things. + */ + if (have_submounts(dentry)) + goto out_valid; + shrink_dcache_parent(dentry); + } + d_drop(dentry); + return 0; +} + +static void sysfs_dentry_iput(struct dentry *dentry, struct inode *inode) { struct sysfs_dirent * sd = dentry->d_fsdata; @@ -307,7 +320,9 @@ static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) } static const struct dentry_operations sysfs_dentry_ops = { - .d_iput = sysfs_d_iput, + .d_revalidate = sysfs_dentry_revalidate, + .d_delete = sysfs_dentry_delete, + .d_iput = sysfs_dentry_iput, }; struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) @@ -344,12 +359,6 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) return NULL; } -static int sysfs_ilookup_test(struct inode *inode, void *arg) -{ - struct sysfs_dirent *sd = arg; - return inode->i_ino == sd->s_ino; -} - /** * sysfs_addrm_start - prepare for sysfs_dirent add/remove * @acxt: pointer to sysfs_addrm_cxt to be used @@ -357,47 +366,20 @@ static int sysfs_ilookup_test(struct inode *inode, void *arg) * * This function is called when the caller is about to add or * remove sysfs_dirent under @parent_sd. This function acquires - * sysfs_mutex, grabs inode for @parent_sd if available and lock - * i_mutex of it. @acxt is used to keep and pass context to + * sysfs_mutex. @acxt is used to keep and pass context to * other addrm functions. * * LOCKING: * Kernel thread context (may sleep). sysfs_mutex is locked on - * return. i_mutex of parent inode is locked on return if - * available. + * return. */ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *parent_sd) { - struct inode *inode; - memset(acxt, 0, sizeof(*acxt)); acxt->parent_sd = parent_sd; - /* Lookup parent inode. inode initialization is protected by - * sysfs_mutex, so inode existence can be determined by - * looking up inode while holding sysfs_mutex. - */ mutex_lock(&sysfs_mutex); - - inode = ilookup5(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test, - parent_sd); - if (inode) { - WARN_ON(inode->i_state & I_NEW); - - /* parent inode available */ - acxt->parent_inode = inode; - - /* sysfs_mutex is below i_mutex in lock hierarchy. - * First, trylock i_mutex. If fails, unlock - * sysfs_mutex and lock them in order. - */ - if (!mutex_trylock(&inode->i_mutex)) { - mutex_unlock(&sysfs_mutex); - mutex_lock(&inode->i_mutex); - mutex_lock(&sysfs_mutex); - } - } } /** @@ -422,18 +404,22 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, */ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) { + struct sysfs_inode_attrs *ps_iattr; + if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) return -EEXIST; sd->s_parent = sysfs_get(acxt->parent_sd); - if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) - inc_nlink(acxt->parent_inode); - - acxt->cnt++; - sysfs_link_sibling(sd); + /* Update timestamps on the parent */ + ps_iattr = acxt->parent_sd->s_iattr; + if (ps_iattr) { + struct iattr *ps_iattrs = &ps_iattr->ia_iattr; + ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; + } + return 0; } @@ -512,70 +498,22 @@ int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) */ void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) { + struct sysfs_inode_attrs *ps_iattr; + BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); sysfs_unlink_sibling(sd); + /* Update timestamps on the parent */ + ps_iattr = acxt->parent_sd->s_iattr; + if (ps_iattr) { + struct iattr *ps_iattrs = &ps_iattr->ia_iattr; + ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; + } + sd->s_flags |= SYSFS_FLAG_REMOVED; sd->s_sibling = acxt->removed; acxt->removed = sd; - - if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) - drop_nlink(acxt->parent_inode); - - acxt->cnt++; -} - -/** - * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent - * @sd: target sysfs_dirent - * - * Drop dentry for @sd. @sd must have been unlinked from its - * parent on entry to this function such that it can't be looked - * up anymore. - */ -static void sysfs_drop_dentry(struct sysfs_dirent *sd) -{ - struct inode *inode; - struct dentry *dentry; - - inode = ilookup(sysfs_sb, sd->s_ino); - if (!inode) - return; - - /* Drop any existing dentries associated with sd. - * - * For the dentry to be properly freed we need to grab a - * reference to the dentry under the dcache lock, unhash it, - * and then put it. The playing with the dentry count allows - * dput to immediately free the dentry if it is not in use. - */ -repeat: - spin_lock(&dcache_lock); - list_for_each_entry(dentry, &inode->i_dentry, d_alias) { - if (d_unhashed(dentry)) - continue; - dget_locked(dentry); - spin_lock(&dentry->d_lock); - __d_drop(dentry); - spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); - dput(dentry); - goto repeat; - } - spin_unlock(&dcache_lock); - - /* adjust nlink and update timestamp */ - mutex_lock(&inode->i_mutex); - - inode->i_ctime = CURRENT_TIME; - drop_nlink(inode); - if (sysfs_type(sd) == SYSFS_DIR) - drop_nlink(inode); - - mutex_unlock(&inode->i_mutex); - - iput(inode); } /** @@ -584,25 +522,15 @@ repeat: * * Finish up sysfs_dirent add/remove. Resources acquired by * sysfs_addrm_start() are released and removed sysfs_dirents are - * cleaned up. Timestamps on the parent inode are updated. + * cleaned up. * * LOCKING: - * All mutexes acquired by sysfs_addrm_start() are released. + * sysfs_mutex is released. */ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) { /* release resources acquired by sysfs_addrm_start() */ mutex_unlock(&sysfs_mutex); - if (acxt->parent_inode) { - struct inode *inode = acxt->parent_inode; - - /* if added/removed, update timestamps on the parent */ - if (acxt->cnt) - inode->i_ctime = inode->i_mtime = CURRENT_TIME; - - mutex_unlock(&inode->i_mutex); - iput(inode); - } /* kill removed sysfs_dirents */ while (acxt->removed) { @@ -611,7 +539,6 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) acxt->removed = sd->s_sibling; sd->s_sibling = NULL; - sysfs_drop_dentry(sd); sysfs_deactivate(sd); unmap_bin_file(sd); sysfs_put(sd); @@ -751,10 +678,15 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, } /* instantiate and hash dentry */ - dentry->d_op = &sysfs_dentry_ops; - dentry->d_fsdata = sysfs_get(sd); - d_instantiate(dentry, inode); - d_rehash(dentry); + ret = d_find_alias(inode); + if (!ret) { + dentry->d_op = &sysfs_dentry_ops; + dentry->d_fsdata = sysfs_get(sd); + d_add(dentry, inode); + } else { + d_move(ret, dentry); + iput(inode); + } out_unlock: mutex_unlock(&sysfs_mutex); @@ -763,7 +695,9 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, const struct inode_operations sysfs_dir_inode_operations = { .lookup = sysfs_lookup, + .permission = sysfs_permission, .setattr = sysfs_setattr, + .getattr = sysfs_getattr, .setxattr = sysfs_setxattr, }; @@ -826,141 +760,65 @@ void sysfs_remove_dir(struct kobject * kobj) __sysfs_remove_dir(sd); } -int sysfs_rename_dir(struct kobject * kobj, const char *new_name) +int sysfs_rename(struct sysfs_dirent *sd, + struct sysfs_dirent *new_parent_sd, const char *new_name) { - struct sysfs_dirent *sd = kobj->sd; - struct dentry *parent = NULL; - struct dentry *old_dentry = NULL, *new_dentry = NULL; const char *dup_name = NULL; int error; - mutex_lock(&sysfs_rename_mutex); + mutex_lock(&sysfs_mutex); error = 0; - if (strcmp(sd->s_name, new_name) == 0) + if ((sd->s_parent == new_parent_sd) && + (strcmp(sd->s_name, new_name) == 0)) goto out; /* nothing to rename */ - /* get the original dentry */ - old_dentry = sysfs_get_dentry(sd); - if (IS_ERR(old_dentry)) { - error = PTR_ERR(old_dentry); - old_dentry = NULL; - goto out; - } - - parent = old_dentry->d_parent; - - /* lock parent and get dentry for new name */ - mutex_lock(&parent->d_inode->i_mutex); - mutex_lock(&sysfs_mutex); - error = -EEXIST; - if (sysfs_find_dirent(sd->s_parent, new_name)) - goto out_unlock; - - error = -ENOMEM; - new_dentry = d_alloc_name(parent, new_name); - if (!new_dentry) - goto out_unlock; + if (sysfs_find_dirent(new_parent_sd, new_name)) + goto out; /* rename sysfs_dirent */ - error = -ENOMEM; - new_name = dup_name = kstrdup(new_name, GFP_KERNEL); - if (!new_name) - goto out_unlock; - - dup_name = sd->s_name; - sd->s_name = new_name; + if (strcmp(sd->s_name, new_name) != 0) { + error = -ENOMEM; + new_name = dup_name = kstrdup(new_name, GFP_KERNEL); + if (!new_name) + goto out; + + dup_name = sd->s_name; + sd->s_name = new_name; + } - /* rename */ - d_add(new_dentry, NULL); - d_move(old_dentry, new_dentry); + /* Remove from old parent's list and insert into new parent's list. */ + if (sd->s_parent != new_parent_sd) { + sysfs_unlink_sibling(sd); + sysfs_get(new_parent_sd); + sysfs_put(sd->s_parent); + sd->s_parent = new_parent_sd; + sysfs_link_sibling(sd); + } error = 0; - out_unlock: + out: mutex_unlock(&sysfs_mutex); - mutex_unlock(&parent->d_inode->i_mutex); kfree(dup_name); - dput(old_dentry); - dput(new_dentry); - out: - mutex_unlock(&sysfs_rename_mutex); return error; } +int sysfs_rename_dir(struct kobject *kobj, const char *new_name) +{ + return sysfs_rename(kobj->sd, kobj->sd->s_parent, new_name); +} + int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) { struct sysfs_dirent *sd = kobj->sd; struct sysfs_dirent *new_parent_sd; - struct dentry *old_parent, *new_parent = NULL; - struct dentry *old_dentry = NULL, *new_dentry = NULL; - int error; - mutex_lock(&sysfs_rename_mutex); BUG_ON(!sd->s_parent); - new_parent_sd = (new_parent_kobj && new_parent_kobj->sd) ? + new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; - error = 0; - if (sd->s_parent == new_parent_sd) - goto out; /* nothing to move */ - - /* get dentries */ - old_dentry = sysfs_get_dentry(sd); - if (IS_ERR(old_dentry)) { - error = PTR_ERR(old_dentry); - old_dentry = NULL; - goto out; - } - old_parent = old_dentry->d_parent; - - new_parent = sysfs_get_dentry(new_parent_sd); - if (IS_ERR(new_parent)) { - error = PTR_ERR(new_parent); - new_parent = NULL; - goto out; - } - -again: - mutex_lock(&old_parent->d_inode->i_mutex); - if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { - mutex_unlock(&old_parent->d_inode->i_mutex); - goto again; - } - mutex_lock(&sysfs_mutex); - - error = -EEXIST; - if (sysfs_find_dirent(new_parent_sd, sd->s_name)) - goto out_unlock; - - error = -ENOMEM; - new_dentry = d_alloc_name(new_parent, sd->s_name); - if (!new_dentry) - goto out_unlock; - - error = 0; - d_add(new_dentry, NULL); - d_move(old_dentry, new_dentry); - - /* Remove from old parent's list and insert into new parent's list. */ - sysfs_unlink_sibling(sd); - sysfs_get(new_parent_sd); - drop_nlink(old_parent->d_inode); - sysfs_put(sd->s_parent); - sd->s_parent = new_parent_sd; - inc_nlink(new_parent->d_inode); - sysfs_link_sibling(sd); - - out_unlock: - mutex_unlock(&sysfs_mutex); - mutex_unlock(&new_parent->d_inode->i_mutex); - mutex_unlock(&old_parent->d_inode->i_mutex); - out: - dput(new_parent); - dput(old_dentry); - dput(new_dentry); - mutex_unlock(&sysfs_rename_mutex); - return error; + return sysfs_rename(sd, new_parent_sd, sd->s_name); } /* Relationship between s_mode and the DT_xxx types */ diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index f5ea4680f15..dc30d9e3168 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -579,46 +579,23 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group); */ int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode) { - struct sysfs_dirent *victim_sd = NULL; - struct dentry *victim = NULL; - struct inode * inode; + struct sysfs_dirent *sd; struct iattr newattrs; int rc; - rc = -ENOENT; - victim_sd = sysfs_get_dirent(kobj->sd, attr->name); - if (!victim_sd) - goto out; + mutex_lock(&sysfs_mutex); - mutex_lock(&sysfs_rename_mutex); - victim = sysfs_get_dentry(victim_sd); - mutex_unlock(&sysfs_rename_mutex); - if (IS_ERR(victim)) { - rc = PTR_ERR(victim); - victim = NULL; + rc = -ENOENT; + sd = sysfs_find_dirent(kobj->sd, attr->name); + if (!sd) goto out; - } - - inode = victim->d_inode; - - mutex_lock(&inode->i_mutex); - newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); - newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; - newattrs.ia_ctime = current_fs_time(inode->i_sb); - rc = sysfs_setattr(victim, &newattrs); + newattrs.ia_mode = (mode & S_IALLUGO) | (sd->s_mode & ~S_IALLUGO); + newattrs.ia_valid = ATTR_MODE; + rc = sysfs_sd_setattr(sd, &newattrs); - if (rc == 0) { - fsnotify_change(victim, newattrs.ia_valid); - mutex_lock(&sysfs_mutex); - victim_sd->s_mode = newattrs.ia_mode; - mutex_unlock(&sysfs_mutex); - } - - mutex_unlock(&inode->i_mutex); out: - dput(victim); - sysfs_put(victim_sd); + mutex_unlock(&sysfs_mutex); return rc; } EXPORT_SYMBOL_GPL(sysfs_chmod_file); diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index e28cecf179f..220b758523a 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -37,7 +37,9 @@ static struct backing_dev_info sysfs_backing_dev_info = { }; static const struct inode_operations sysfs_inode_operations ={ + .permission = sysfs_permission, .setattr = sysfs_setattr, + .getattr = sysfs_getattr, .setxattr = sysfs_setxattr, }; @@ -46,7 +48,7 @@ int __init sysfs_inode_init(void) return bdi_init(&sysfs_backing_dev_info); } -struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) +static struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) { struct sysfs_inode_attrs *attrs; struct iattr *iattrs; @@ -64,30 +66,15 @@ struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) return attrs; } -int sysfs_setattr(struct dentry * dentry, struct iattr * iattr) + +int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr * iattr) { - struct inode * inode = dentry->d_inode; - struct sysfs_dirent * sd = dentry->d_fsdata; struct sysfs_inode_attrs *sd_attrs; struct iattr *iattrs; unsigned int ia_valid = iattr->ia_valid; - int error; - - if (!sd) - return -EINVAL; sd_attrs = sd->s_iattr; - error = inode_change_ok(inode, iattr); - if (error) - return error; - - iattr->ia_valid &= ~ATTR_SIZE; /* ignore size changes */ - - error = inode_setattr(inode, iattr); - if (error) - return error; - if (!sd_attrs) { /* setting attributes for the first time, allocate now */ sd_attrs = sysfs_init_inode_attrs(sd); @@ -103,42 +90,78 @@ int sysfs_setattr(struct dentry * dentry, struct iattr * iattr) if (ia_valid & ATTR_GID) iattrs->ia_gid = iattr->ia_gid; if (ia_valid & ATTR_ATIME) - iattrs->ia_atime = timespec_trunc(iattr->ia_atime, - inode->i_sb->s_time_gran); + iattrs->ia_atime = iattr->ia_atime; if (ia_valid & ATTR_MTIME) - iattrs->ia_mtime = timespec_trunc(iattr->ia_mtime, - inode->i_sb->s_time_gran); + iattrs->ia_mtime = iattr->ia_mtime; if (ia_valid & ATTR_CTIME) - iattrs->ia_ctime = timespec_trunc(iattr->ia_ctime, - inode->i_sb->s_time_gran); + iattrs->ia_ctime = iattr->ia_ctime; if (ia_valid & ATTR_MODE) { umode_t mode = iattr->ia_mode; - - if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID)) - mode &= ~S_ISGID; iattrs->ia_mode = sd->s_mode = mode; } } + return 0; +} + +int sysfs_setattr(struct dentry *dentry, struct iattr *iattr) +{ + struct inode *inode = dentry->d_inode; + struct sysfs_dirent *sd = dentry->d_fsdata; + int error; + + if (!sd) + return -EINVAL; + + error = inode_change_ok(inode, iattr); + if (error) + return error; + + iattr->ia_valid &= ~ATTR_SIZE; /* ignore size changes */ + + error = inode_setattr(inode, iattr); + if (error) + return error; + + mutex_lock(&sysfs_mutex); + error = sysfs_sd_setattr(sd, iattr); + mutex_unlock(&sysfs_mutex); + return error; } +static int sysfs_sd_setsecdata(struct sysfs_dirent *sd, void **secdata, u32 *secdata_len) +{ + struct sysfs_inode_attrs *iattrs; + void *old_secdata; + size_t old_secdata_len; + + iattrs = sd->s_iattr; + if (!iattrs) + iattrs = sysfs_init_inode_attrs(sd); + if (!iattrs) + return -ENOMEM; + + old_secdata = iattrs->ia_secdata; + old_secdata_len = iattrs->ia_secdata_len; + + iattrs->ia_secdata = *secdata; + iattrs->ia_secdata_len = *secdata_len; + + *secdata = old_secdata; + *secdata_len = old_secdata_len; + return 0; +} + int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { struct sysfs_dirent *sd = dentry->d_fsdata; - struct sysfs_inode_attrs *iattrs; void *secdata; int error; u32 secdata_len = 0; if (!sd) return -EINVAL; - if (!sd->s_iattr) - sd->s_iattr = sysfs_init_inode_attrs(sd); - if (!sd->s_iattr) - return -ENOMEM; - - iattrs = sd->s_iattr; if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; @@ -150,12 +173,13 @@ int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, &secdata, &secdata_len); if (error) goto out; - if (iattrs->ia_secdata) - security_release_secctx(iattrs->ia_secdata, - iattrs->ia_secdata_len); - iattrs->ia_secdata = secdata; - iattrs->ia_secdata_len = secdata_len; + mutex_lock(&sysfs_mutex); + error = sysfs_sd_setsecdata(sd, &secdata, &secdata_len); + mutex_unlock(&sysfs_mutex); + + if (secdata) + security_release_secctx(secdata, secdata_len); } else return -EINVAL; out: @@ -170,7 +194,6 @@ static inline void set_default_inode_attr(struct inode * inode, mode_t mode) static inline void set_inode_attr(struct inode * inode, struct iattr * iattr) { - inode->i_mode = iattr->ia_mode; inode->i_uid = iattr->ia_uid; inode->i_gid = iattr->ia_gid; inode->i_atime = iattr->ia_atime; @@ -178,17 +201,6 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr) inode->i_ctime = iattr->ia_ctime; } - -/* - * sysfs has a different i_mutex lock order behavior for i_mutex than other - * filesystems; sysfs i_mutex is called in many places with subsystem locks - * held. At the same time, many of the VFS locking rules do not apply to - * sysfs at all (cross directory rename for example). To untangle this mess - * (which gives false positives in lockdep), we're giving sysfs inodes their - * own class for i_mutex. - */ -static struct lock_class_key sysfs_inode_imutex_key; - static int sysfs_count_nlink(struct sysfs_dirent *sd) { struct sysfs_dirent *child; @@ -201,38 +213,55 @@ static int sysfs_count_nlink(struct sysfs_dirent *sd) return nr + 2; } +static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode) +{ + struct sysfs_inode_attrs *iattrs = sd->s_iattr; + + inode->i_mode = sd->s_mode; + if (iattrs) { + /* sysfs_dirent has non-default attributes + * get them from persistent copy in sysfs_dirent + */ + set_inode_attr(inode, &iattrs->ia_iattr); + security_inode_notifysecctx(inode, + iattrs->ia_secdata, + iattrs->ia_secdata_len); + } + + if (sysfs_type(sd) == SYSFS_DIR) + inode->i_nlink = sysfs_count_nlink(sd); +} + +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + struct inode *inode = dentry->d_inode; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + generic_fillattr(inode, stat); + return 0; +} + static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) { struct bin_attribute *bin_attr; - struct sysfs_inode_attrs *iattrs; inode->i_private = sysfs_get(sd); inode->i_mapping->a_ops = &sysfs_aops; inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; inode->i_op = &sysfs_inode_operations; - inode->i_ino = sd->s_ino; - lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key); - iattrs = sd->s_iattr; - if (iattrs) { - /* sysfs_dirent has non-default attributes - * get them for the new inode from persistent copy - * in sysfs_dirent - */ - set_inode_attr(inode, &iattrs->ia_iattr); - if (iattrs->ia_secdata) - security_inode_notifysecctx(inode, - iattrs->ia_secdata, - iattrs->ia_secdata_len); - } else - set_default_inode_attr(inode, sd->s_mode); + set_default_inode_attr(inode, sd->s_mode); + sysfs_refresh_inode(sd, inode); /* initialize inode according to type */ switch (sysfs_type(sd)) { case SYSFS_DIR: inode->i_op = &sysfs_dir_inode_operations; inode->i_fop = &sysfs_dir_operations; - inode->i_nlink = sysfs_count_nlink(sd); break; case SYSFS_KOBJ_ATTR: inode->i_size = PAGE_SIZE; @@ -315,3 +344,14 @@ int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name) else return -ENOENT; } + +int sysfs_permission(struct inode *inode, int mask) +{ + struct sysfs_dirent *sd = inode->i_private; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + return generic_permission(inode, mask, NULL); +} diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index c5081ad7702..c5eff49fa41 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -210,10 +210,13 @@ static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd, void *co } const struct inode_operations sysfs_symlink_inode_operations = { - .setxattr = sysfs_setxattr, - .readlink = generic_readlink, - .follow_link = sysfs_follow_link, - .put_link = sysfs_put_link, + .setxattr = sysfs_setxattr, + .readlink = generic_readlink, + .follow_link = sysfs_follow_link, + .put_link = sysfs_put_link, + .setattr = sysfs_setattr, + .getattr = sysfs_getattr, + .permission = sysfs_permission, }; diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index af4c4e7482a..ca52e7b9d8f 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -89,9 +89,7 @@ static inline unsigned int sysfs_type(struct sysfs_dirent *sd) */ struct sysfs_addrm_cxt { struct sysfs_dirent *parent_sd; - struct inode *parent_inode; struct sysfs_dirent *removed; - int cnt; }; /* @@ -105,7 +103,6 @@ extern struct kmem_cache *sysfs_dir_cachep; * dir.c */ extern struct mutex sysfs_mutex; -extern struct mutex sysfs_rename_mutex; extern spinlock_t sysfs_assoc_lock; extern const struct file_operations sysfs_dir_operations; @@ -133,6 +130,9 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name, struct sysfs_dirent **p_sd); void sysfs_remove_subdir(struct sysfs_dirent *sd); +int sysfs_rename(struct sysfs_dirent *sd, + struct sysfs_dirent *new_parent_sd, const char *new_name); + static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd) { if (sd) { @@ -155,7 +155,10 @@ static inline void __sysfs_put(struct sysfs_dirent *sd) */ struct inode *sysfs_get_inode(struct sysfs_dirent *sd); void sysfs_delete_inode(struct inode *inode); +int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr); +int sysfs_permission(struct inode *inode, int mask); int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name); |