diff options
Diffstat (limited to 'fs')
52 files changed, 715 insertions, 676 deletions
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 9ee5343..3662f1d 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -1127,7 +1127,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr) } /* Write all dirty data */ - if (S_ISREG(dentry->d_inode->i_mode)) + if (d_is_reg(dentry)) filemap_write_and_wait(dentry->d_inode->i_mapping); retval = p9_client_wstat(fid, &wstat); @@ -1285,7 +1285,7 @@ SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp) ret = -EINVAL; if (unlikely(ctx || nr_events == 0)) { - pr_debug("EINVAL: io_setup: ctx %lu nr_events %u\n", + pr_debug("EINVAL: ctx %lu nr_events %u\n", ctx, nr_events); goto out; } @@ -1333,7 +1333,7 @@ SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx) return ret; } - pr_debug("EINVAL: io_destroy: invalid context id\n"); + pr_debug("EINVAL: invalid context id\n"); return -EINVAL; } @@ -1515,7 +1515,7 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) || ((ssize_t)iocb->aio_nbytes < 0) )) { - pr_debug("EINVAL: io_submit: overflow check\n"); + pr_debug("EINVAL: overflow check\n"); return -EINVAL; } diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c index aaf96cb..ac7d921 100644 --- a/fs/autofs4/dev-ioctl.c +++ b/fs/autofs4/dev-ioctl.c @@ -95,7 +95,7 @@ static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param) */ static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in) { - struct autofs_dev_ioctl tmp; + struct autofs_dev_ioctl tmp, *res; if (copy_from_user(&tmp, in, sizeof(tmp))) return ERR_PTR(-EFAULT); @@ -106,7 +106,11 @@ static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *i if (tmp.size > (PATH_MAX + sizeof(tmp))) return ERR_PTR(-ENAMETOOLONG); - return memdup_user(in, tmp.size); + res = memdup_user(in, tmp.size); + if (!IS_ERR(res)) + res->size = tmp.size; + + return res; } static inline void free_dev_ioctl(struct autofs_dev_ioctl *param) diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index bfdbaba..11dd118 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -374,7 +374,7 @@ static struct dentry *should_expire(struct dentry *dentry, return NULL; } - if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { + if (dentry->d_inode && d_is_symlink(dentry)) { DPRINTK("checking symlink %p %pd", dentry, dentry); /* * A symlink can't be "busy" in the usual sense so diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index dbb5b72..7e44fdd 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -108,7 +108,7 @@ static int autofs4_dir_open(struct inode *inode, struct file *file) struct dentry *dentry = file->f_path.dentry; struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); - DPRINTK("file=%p dentry=%p %pD", file, dentry, dentry); + DPRINTK("file=%p dentry=%p %pd", file, dentry, dentry); if (autofs4_oz_mode(sbi)) goto out; @@ -371,7 +371,7 @@ static struct vfsmount *autofs4_d_automount(struct path *path) * having d_mountpoint() true, so there's no need to call back * to the daemon. */ - if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { + if (dentry->d_inode && d_is_symlink(dentry)) { spin_unlock(&sbi->fs_lock); goto done; } @@ -485,7 +485,7 @@ static int autofs4_d_manage(struct dentry *dentry, bool rcu_walk) * an incorrect ELOOP error return. */ if ((!d_mountpoint(dentry) && !simple_empty(dentry)) || - (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode))) + (dentry->d_inode && d_is_symlink(dentry))) status = -EISDIR; } spin_unlock(&sbi->fs_lock); diff --git a/fs/bad_inode.c b/fs/bad_inode.c index afd2b44..861b1e1 100644 --- a/fs/bad_inode.c +++ b/fs/bad_inode.c @@ -15,161 +15,14 @@ #include <linux/namei.h> #include <linux/poll.h> - -static loff_t bad_file_llseek(struct file *file, loff_t offset, int whence) -{ - return -EIO; -} - -static ssize_t bad_file_read(struct file *filp, char __user *buf, - size_t size, loff_t *ppos) -{ - return -EIO; -} - -static ssize_t bad_file_write(struct file *filp, const char __user *buf, - size_t siz, loff_t *ppos) -{ - return -EIO; -} - -static ssize_t bad_file_aio_read(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) -{ - return -EIO; -} - -static ssize_t bad_file_aio_write(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) -{ - return -EIO; -} - -static int bad_file_readdir(struct file *file, struct dir_context *ctx) -{ - return -EIO; -} - -static unsigned int bad_file_poll(struct file *filp, poll_table *wait) -{ - return POLLERR; -} - -static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd, - unsigned long arg) -{ - return -EIO; -} - -static long bad_file_compat_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - return -EIO; -} - -static int bad_file_mmap(struct file *file, struct vm_area_struct *vma) -{ - return -EIO; -} - static int bad_file_open(struct inode *inode, struct file *filp) { return -EIO; } -static int bad_file_flush(struct file *file, fl_owner_t id) -{ - return -EIO; -} - -static int bad_file_release(struct inode *inode, struct file *filp) -{ - return -EIO; -} - -static int bad_file_fsync(struct file *file, loff_t start, loff_t end, - int datasync) -{ - return -EIO; -} - -static int bad_file_aio_fsync(struct kiocb *iocb, int datasync) -{ - return -EIO; -} - -static int bad_file_fasync(int fd, struct file *filp, int on) -{ - return -EIO; -} - -static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl) -{ - return -EIO; -} - -static ssize_t bad_file_sendpage(struct file *file, struct page *page, - int off, size_t len, loff_t *pos, int more) -{ - return -EIO; -} - -static unsigned long bad_file_get_unmapped_area(struct file *file, - unsigned long addr, unsigned long len, - unsigned long pgoff, unsigned long flags) -{ - return -EIO; -} - -static int bad_file_check_flags(int flags) -{ - return -EIO; -} - -static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl) -{ - return -EIO; -} - -static ssize_t bad_file_splice_write(struct pipe_inode_info *pipe, - struct file *out, loff_t *ppos, size_t len, - unsigned int flags) -{ - return -EIO; -} - -static ssize_t bad_file_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) -{ - return -EIO; -} - static const struct file_operations bad_file_ops = { - .llseek = bad_file_llseek, - .read = bad_file_read, - .write = bad_file_write, - .aio_read = bad_file_aio_read, - .aio_write = bad_file_aio_write, - .iterate = bad_file_readdir, - .poll = bad_file_poll, - .unlocked_ioctl = bad_file_unlocked_ioctl, - .compat_ioctl = bad_file_compat_ioctl, - .mmap = bad_file_mmap, .open = bad_file_open, - .flush = bad_file_flush, - .release = bad_file_release, - .fsync = bad_file_fsync, - .aio_fsync = bad_file_aio_fsync, - .fasync = bad_file_fasync, - .lock = bad_file_lock, - .sendpage = bad_file_sendpage, - .get_unmapped_area = bad_file_get_unmapped_area, - .check_flags = bad_file_check_flags, - .flock = bad_file_flock, - .splice_write = bad_file_splice_write, - .splice_read = bad_file_splice_read, }; static int bad_inode_create (struct inode *dir, struct dentry *dentry, diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index d49fe8a..74609b9 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -776,11 +776,11 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) return -EPERM; if (isdir) { - if (!S_ISDIR(victim->d_inode->i_mode)) + if (!d_is_dir(victim)) return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; - } else if (S_ISDIR(victim->d_inode->i_mode)) + } else if (d_is_dir(victim)) return -EISDIR; if (IS_DEADDIR(dir)) return -ENOENT; diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index ce1b115..f601def 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -574,7 +574,7 @@ static int cachefiles_daemon_cull(struct cachefiles_cache *cache, char *args) /* extract the directory dentry from the cwd */ get_fs_pwd(current->fs, &path); - if (!S_ISDIR(path.dentry->d_inode->i_mode)) + if (!d_can_lookup(path.dentry)) goto notdir; cachefiles_begin_secure(cache, &saved_cred); @@ -646,7 +646,7 @@ static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) /* extract the directory dentry from the cwd */ get_fs_pwd(current->fs, &path); - if (!S_ISDIR(path.dentry->d_inode->i_mode)) + if (!d_can_lookup(path.dentry)) goto notdir; cachefiles_begin_secure(cache, &saved_cred); diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index 1c7293c..2324262 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -437,7 +437,7 @@ static int cachefiles_attr_changed(struct fscache_object *_object) if (!object->backer) return -ENOBUFS; - ASSERT(S_ISREG(object->backer->d_inode->i_mode)); + ASSERT(d_is_reg(object->backer)); fscache_set_store_limit(&object->fscache, ni_size); @@ -501,7 +501,7 @@ static void cachefiles_invalidate_object(struct fscache_operation *op) op->object->debug_id, (unsigned long long)ni_size); if (object->backer) { - ASSERT(S_ISREG(object->backer->d_inode->i_mode)); + ASSERT(d_is_reg(object->backer)); fscache_set_store_limit(&object->fscache, ni_size); diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 7f8e83f..1e51714e 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -277,7 +277,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache, _debug("remove %p from %p", rep, dir); /* non-directories can just be unlinked */ - if (!S_ISDIR(rep->d_inode->i_mode)) { + if (!d_is_dir(rep)) { _debug("unlink stale object"); path.mnt = cache->mnt; @@ -323,7 +323,7 @@ try_again: return 0; } - if (!S_ISDIR(cache->graveyard->d_inode->i_mode)) { + if (!d_can_lookup(cache->graveyard)) { unlock_rename(cache->graveyard, dir); cachefiles_io_error(cache, "Graveyard no longer a directory"); return -EIO; @@ -475,7 +475,7 @@ int cachefiles_walk_to_object(struct cachefiles_object *parent, ASSERT(parent->dentry); ASSERT(parent->dentry->d_inode); - if (!(S_ISDIR(parent->dentry->d_inode->i_mode))) { + if (!(d_is_dir(parent->dentry))) { // TODO: convert file to dir _leave("looking up in none directory"); return -ENOBUFS; @@ -539,7 +539,7 @@ lookup_again: _debug("mkdir -> %p{%p{ino=%lu}}", next, next->d_inode, next->d_inode->i_ino); - } else if (!S_ISDIR(next->d_inode->i_mode)) { + } else if (!d_can_lookup(next)) { pr_err("inode %lu is not a directory\n", next->d_inode->i_ino); ret = -ENOBUFS; @@ -568,8 +568,8 @@ lookup_again: _debug("create -> %p{%p{ino=%lu}}", next, next->d_inode, next->d_inode->i_ino); - } else if (!S_ISDIR(next->d_inode->i_mode) && - !S_ISREG(next->d_inode->i_mode) + } else if (!d_can_lookup(next) && + !d_is_reg(next) ) { pr_err("inode %lu is not a file or directory\n", next->d_inode->i_ino); @@ -642,7 +642,7 @@ lookup_again: /* open a file interface onto a data file */ if (object->type != FSCACHE_COOKIE_TYPE_INDEX) { - if (S_ISREG(object->dentry->d_inode->i_mode)) { + if (d_is_reg(object->dentry)) { const struct address_space_operations *aops; ret = -EPERM; @@ -763,7 +763,7 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, /* we need to make sure the subdir is a directory */ ASSERT(subdir->d_inode); - if (!S_ISDIR(subdir->d_inode->i_mode)) { + if (!d_can_lookup(subdir)) { pr_err("%s is not a directory\n", dirname); ret = -EIO; goto check_error; diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c index 616db0e7..c6cd8d7 100644 --- a/fs/cachefiles/rdwr.c +++ b/fs/cachefiles/rdwr.c @@ -900,7 +900,7 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page) return -ENOBUFS; } - ASSERT(S_ISREG(object->backer->d_inode->i_mode)); + ASSERT(d_is_reg(object->backer)); cache = container_of(object->fscache.cache, struct cachefiles_cache, cache); diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 0411dbb..83e9976 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -904,7 +904,7 @@ static int ceph_unlink(struct inode *dir, struct dentry *dentry) } else if (ceph_snap(dir) == CEPH_NOSNAP) { dout("unlink/rmdir dir %p dn %p inode %p\n", dir, dentry, inode); - op = S_ISDIR(dentry->d_inode->i_mode) ? + op = d_is_dir(dentry) ? CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK; } else goto out; diff --git a/fs/ceph/file.c b/fs/ceph/file.c index a3d774b..d533075 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -292,7 +292,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, } if (err) goto out_req; - if (dn || dentry->d_inode == NULL || S_ISLNK(dentry->d_inode->i_mode)) { + if (dn || dentry->d_inode == NULL || d_is_symlink(dentry)) { /* make vfs retry on splice, ENOENT, or symlink */ dout("atomic_open finish_no_open on dn %p\n", dn); err = finish_no_open(file, dn); diff --git a/fs/coda/dir.c b/fs/coda/dir.c index 281ee01..60cb88c 100644 --- a/fs/coda/dir.c +++ b/fs/coda/dir.c @@ -304,7 +304,7 @@ static int coda_rename(struct inode *old_dir, struct dentry *old_dentry, (const char *) old_name, (const char *)new_name); if (!error) { if (new_dentry->d_inode) { - if (S_ISDIR(new_dentry->d_inode->i_mode)) { + if (d_is_dir(new_dentry)) { coda_dir_drop_nlink(old_dir); coda_dir_inc_nlink(new_dir); } diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h index a315677..b65d1ef 100644 --- a/fs/configfs/configfs_internal.h +++ b/fs/configfs/configfs_internal.h @@ -69,14 +69,13 @@ extern struct kmem_cache *configfs_dir_cachep; extern int configfs_is_root(struct config_item *item); extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *); -extern int configfs_create(struct dentry *, umode_t mode, int (*init)(struct inode *)); +extern int configfs_create(struct dentry *, umode_t mode, void (*init)(struct inode *)); extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); extern int configfs_make_dirent(struct configfs_dirent *, struct dentry *, void *, umode_t, int); extern int configfs_dirent_is_ready(struct configfs_dirent *); -extern int configfs_add_file(struct dentry *, const struct configfs_attribute *, int); extern void configfs_hash_and_remove(struct dentry * dir, const char * name); extern const unsigned char * configfs_get_name(struct configfs_dirent *sd); diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index c9c298b..cf0db00 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -240,60 +240,26 @@ int configfs_make_dirent(struct configfs_dirent * parent_sd, return 0; } -static int init_dir(struct inode * inode) +static void init_dir(struct inode * inode) { inode->i_op = &configfs_dir_inode_operations; inode->i_fop = &configfs_dir_operations; /* directory inodes start off with i_nlink == 2 (for "." entry) */ inc_nlink(inode); - return 0; } -static int configfs_init_file(struct inode * inode) +static void configfs_init_file(struct inode * inode) { inode->i_size = PAGE_SIZE; inode->i_fop = &configfs_file_operations; - return 0; } -static int init_symlink(struct inode * inode) +static void init_symlink(struct inode * inode) { inode->i_op = &configfs_symlink_inode_operations; - return 0; -} - -static int create_dir(struct config_item *k, struct dentry *d) -{ - int error; - umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; - struct dentry *p = d->d_parent; - - BUG_ON(!k); - - error = configfs_dirent_exists(p->d_fsdata, d->d_name.name); - if (!error) - error = configfs_make_dirent(p->d_fsdata, d, k, mode, - CONFIGFS_DIR | CONFIGFS_USET_CREATING); - if (!error) { - configfs_set_dir_dirent_depth(p->d_fsdata, d->d_fsdata); - error = configfs_create(d, mode, init_dir); - if (!error) { - inc_nlink(p->d_inode); - } else { - struct configfs_dirent *sd = d->d_fsdata; - if (sd) { - spin_lock(&configfs_dirent_lock); - list_del_init(&sd->s_sibling); - spin_unlock(&configfs_dirent_lock); - configfs_put(sd); - } - } - } - return error; } - /** * configfs_create_dir - create a directory for an config_item. * @item: config_itemwe're creating directory for. @@ -303,11 +269,37 @@ static int create_dir(struct config_item *k, struct dentry *d) * until it is validated by configfs_dir_set_ready() */ -static int configfs_create_dir(struct config_item * item, struct dentry *dentry) +static int configfs_create_dir(struct config_item *item, struct dentry *dentry) { - int error = create_dir(item, dentry); - if (!error) + int error; + umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; + struct dentry *p = dentry->d_parent; + + BUG_ON(!item); + + error = configfs_dirent_exists(p->d_fsdata, dentry->d_name.name); + if (unlikely(error)) + return error; + + error = configfs_make_dirent(p->d_fsdata, dentry, item, mode, + CONFIGFS_DIR | CONFIGFS_USET_CREATING); + if (unlikely(error)) + return error; + + configfs_set_dir_dirent_depth(p->d_fsdata, dentry->d_fsdata); + error = configfs_create(dentry, mode, init_dir); + if (!error) { + inc_nlink(p->d_inode); item->ci_dentry = dentry; + } else { + struct configfs_dirent *sd = dentry->d_fsdata; + if (sd) { + spin_lock(&configfs_dirent_lock); + list_del_init(&sd->s_sibling); + spin_unlock(&configfs_dirent_lock); + configfs_put(sd); + } + } return error; } diff --git a/fs/configfs/file.c b/fs/configfs/file.c index 1d1c41f..56d2cdc 100644 --- a/fs/configfs/file.c +++ b/fs/configfs/file.c @@ -313,21 +313,6 @@ const struct file_operations configfs_file_operations = { .release = configfs_release, }; - -int configfs_add_file(struct dentry * dir, const struct configfs_attribute * attr, int type) -{ - struct configfs_dirent * parent_sd = dir->d_fsdata; - umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG; - int error = 0; - - mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_NORMAL); - error = configfs_make_dirent(parent_sd, NULL, (void *) attr, mode, type); - mutex_unlock(&dir->d_inode->i_mutex); - - return error; -} - - /** * configfs_create_file - create an attribute file for an item. * @item: item we're creating for. @@ -336,9 +321,16 @@ int configfs_add_file(struct dentry * dir, const struct configfs_attribute * att int configfs_create_file(struct config_item * item, const struct configfs_attribute * attr) { - BUG_ON(!item || !item->ci_dentry || !attr); + struct dentry *dir = item->ci_dentry; + struct configfs_dirent *parent_sd = dir->d_fsdata; + umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG; + int error = 0; - return configfs_add_file(item->ci_dentry, attr, - CONFIGFS_ITEM_ATTR); + mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_NORMAL); + error = configfs_make_dirent(parent_sd, NULL, (void *) attr, mode, + CONFIGFS_ITEM_ATTR); + mutex_unlock(&dir->d_inode->i_mutex); + + return error; } diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c index 65af861..5423a6a 100644 --- a/fs/configfs/inode.c +++ b/fs/configfs/inode.c @@ -176,7 +176,7 @@ static void configfs_set_inode_lock_class(struct configfs_dirent *sd, #endif /* CONFIG_LOCKDEP */ -int configfs_create(struct dentry * dentry, umode_t mode, int (*init)(struct inode *)) +int configfs_create(struct dentry * dentry, umode_t mode, void (*init)(struct inode *)) { int error = 0; struct inode *inode = NULL; @@ -198,13 +198,7 @@ int configfs_create(struct dentry * dentry, umode_t mode, int (*init)(struct ino p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME; configfs_set_inode_lock_class(sd, inode); - if (init) { - error = init(inode); - if (error) { - iput(inode); - return error; - } - } + init(inode); d_instantiate(dentry, inode); if (S_ISDIR(mode) || S_ISLNK(mode)) dget(dentry); /* pin link and directory dentries in core */ @@ -242,7 +236,7 @@ void configfs_drop_dentry(struct configfs_dirent * sd, struct dentry * parent) if (dentry) { spin_lock(&dentry->d_lock); - if (!(d_unhashed(dentry) && dentry->d_inode)) { + if (!d_unhashed(dentry) && dentry->d_inode) { dget_dlock(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); diff --git a/fs/coredump.c b/fs/coredump.c index b5c86ff..f319926 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -572,7 +572,7 @@ void do_coredump(const siginfo_t *siginfo) * * Normally core limits are irrelevant to pipes, since * we're not writing to the file system, but we use - * cprm.limit of 1 here as a speacial value, this is a + * cprm.limit of 1 here as a special value, this is a * consistent way to catch recursive crashes. * We can still crash if the core_pattern binary sets * RLIM_CORE = !1, but it runs as root, and can do diff --git a/fs/dcache.c b/fs/dcache.c index dc400fd..c71e373 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1659,9 +1659,25 @@ void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op) } EXPORT_SYMBOL(d_set_d_op); + +/* + * d_set_fallthru - Mark a dentry as falling through to a lower layer + * @dentry - The dentry to mark + * + * Mark a dentry as falling through to the lower layer (as set with + * d_pin_lower()). This flag may be recorded on the medium. + */ +void d_set_fallthru(struct dentry *dentry) +{ + spin_lock(&dentry->d_lock); + dentry->d_flags |= DCACHE_FALLTHRU; + spin_unlock(&dentry->d_lock); +} +EXPORT_SYMBOL(d_set_fallthru); + static unsigned d_flags_for_inode(struct inode *inode) { - unsigned add_flags = DCACHE_FILE_TYPE; + unsigned add_flags = DCACHE_REGULAR_TYPE; if (!inode) return DCACHE_MISS_TYPE; @@ -1674,13 +1690,21 @@ static unsigned d_flags_for_inode(struct inode *inode) else inode->i_opflags |= IOP_LOOKUP; } - } else if (unlikely(!(inode->i_opflags & IOP_NOFOLLOW))) { - if (unlikely(inode->i_op->follow_link)) + goto type_determined; + } + + if (unlikely(!(inode->i_opflags & IOP_NOFOLLOW))) { + if (unlikely(inode->i_op->follow_link)) { add_flags = DCACHE_SYMLINK_TYPE; - else - inode->i_opflags |= IOP_NOFOLLOW; + goto type_determined; + } + inode->i_opflags |= IOP_NOFOLLOW; } + if (unlikely(!S_ISREG(inode->i_mode))) + add_flags = DCACHE_SPECIAL_TYPE; + +type_determined: if (unlikely(IS_AUTOMOUNT(inode))) add_flags |= DCACHE_NEED_AUTOMOUNT; return add_flags; @@ -1691,7 +1715,8 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode) unsigned add_flags = d_flags_for_inode(inode); spin_lock(&dentry->d_lock); - __d_set_type(dentry, add_flags); + dentry->d_flags &= ~(DCACHE_ENTRY_TYPE | DCACHE_FALLTHRU); + dentry->d_flags |= add_flags; if (inode) hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry); dentry->d_inode = inode; diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 45b18a5..96400ab 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -169,10 +169,19 @@ static int debugfs_show_options(struct seq_file *m, struct dentry *root) return 0; } +static void debugfs_evict_inode(struct inode *inode) +{ + truncate_inode_pages_final(&inode->i_data); + clear_inode(inode); + if (S_ISLNK(inode->i_mode)) + kfree(inode->i_private); +} + static const struct super_operations debugfs_super_operations = { .statfs = simple_statfs, .remount_fs = debugfs_remount, .show_options = debugfs_show_options, + .evict_inode = debugfs_evict_inode, }; static struct vfsmount *debugfs_automount(struct path *path) @@ -511,23 +520,14 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent) int ret = 0; if (debugfs_positive(dentry)) { - if (dentry->d_inode) { - dget(dentry); - switch (dentry->d_inode->i_mode & S_IFMT) { - case S_IFDIR: - ret = simple_rmdir(parent->d_inode, dentry); - break; - case S_IFLNK: - kfree(dentry->d_inode->i_private); - /* fall through */ - default: - simple_unlink(parent->d_inode, dentry); - break; - } - if (!ret) - d_delete(dentry); - dput(dentry); - } + dget(dentry); + if (S_ISDIR(dentry->d_inode->i_mode)) + ret = simple_rmdir(parent->d_inode, dentry); + else + simple_unlink(parent->d_inode, dentry); + if (!ret) + d_delete(dentry); + dput(dentry); } return ret; } @@ -690,7 +690,7 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, } d_move(old_dentry, dentry); fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, - S_ISDIR(old_dentry->d_inode->i_mode), + d_is_dir(old_dentry), NULL, old_dentry); fsnotify_oldname_free(old_name); unlock_rename(new_dir, old_dir); diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 6f4e659..b07731e 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -230,7 +230,7 @@ static int ecryptfs_open(struct inode *inode, struct file *file) } ecryptfs_set_file_lower( file, ecryptfs_inode_to_private(inode)->lower_file); - if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) { + if (d_is_dir(ecryptfs_dentry)) { ecryptfs_printk(KERN_DEBUG, "This is a directory\n"); mutex_lock(&crypt_stat->cs_mutex); crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 34b36a5..b08b518 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -907,9 +907,9 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) lower_inode = ecryptfs_inode_to_lower(inode); lower_dentry = ecryptfs_dentry_to_lower(dentry); mutex_lock(&crypt_stat->cs_mutex); - if (S_ISDIR(dentry->d_inode->i_mode)) + if (d_is_dir(dentry)) crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); - else if (S_ISREG(dentry->d_inode->i_mode) + else if (d_is_reg(dentry) && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED) || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) { struct ecryptfs_mount_crypt_stat *mount_crypt_stat; diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index fdfd206..714cd37 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -429,7 +429,7 @@ struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid, if (IS_ERR(result)) return result; - if (S_ISDIR(result->d_inode->i_mode)) { + if (d_is_dir(result)) { /* * This request is for a directory. * diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 073657f..e907052 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -769,9 +769,9 @@ static long __writeback_inodes_wb(struct bdi_writeback *wb, struct inode *inode = wb_inode(wb->b_io.prev); struct super_block *sb = inode->i_sb; - if (!grab_super_passive(sb)) { + if (!trylock_super(sb)) { /* - * grab_super_passive() may fail consistently due to + * trylock_super() may fail consistently due to * s_umount being grabbed by someone else. Don't use * requeue_io() to avoid busy retrying the inode/sb. */ @@ -779,7 +779,7 @@ static long __writeback_inodes_wb(struct bdi_writeback *wb, continue; } wrote += writeback_sb_inodes(sb, wb, work); - drop_super(sb); + up_read(&sb->s_umount); /* refer to the same tests at the end of writeback_sb_inodes */ if (wrote) { diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 08e7b1a..1545b71 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -971,7 +971,7 @@ int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid, err = -EBUSY; goto badentry; } - if (S_ISDIR(entry->d_inode->i_mode)) { + if (d_is_dir(entry)) { shrink_dcache_parent(entry); if (!simple_empty(entry)) { err = -ENOTEMPTY; diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c index 6371192..487527b 100644 --- a/fs/gfs2/dir.c +++ b/fs/gfs2/dir.c @@ -1809,7 +1809,7 @@ int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry) gfs2_consist_inode(dip); dip->i_entries--; dip->i_inode.i_mtime = dip->i_inode.i_ctime = tv; - if (S_ISDIR(dentry->d_inode->i_mode)) + if (d_is_dir(dentry)) drop_nlink(&dip->i_inode); mark_inode_dirty(&dip->i_inode); diff --git a/fs/hfsplus/dir.c b/fs/hfsplus/dir.c index 435bea2..f0235c1 100644 --- a/fs/hfsplus/dir.c +++ b/fs/hfsplus/dir.c @@ -530,7 +530,7 @@ static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry, /* Unlink destination if it already exists */ if (new_dentry->d_inode) { - if (S_ISDIR(new_dentry->d_inode->i_mode)) + if (d_is_dir(new_dentry)) res = hfsplus_rmdir(new_dir, new_dentry); else res = hfsplus_unlink(new_dir, new_dentry); diff --git a/fs/hppfs/hppfs.c b/fs/hppfs/hppfs.c index 5f27551..043ac9d 100644 --- a/fs/hppfs/hppfs.c +++ b/fs/hppfs/hppfs.c @@ -678,10 +678,10 @@ static struct inode *get_inode(struct super_block *sb, struct dentry *dentry) return NULL; } - if (S_ISDIR(dentry->d_inode->i_mode)) { + if (d_is_dir(dentry)) { inode->i_op = &hppfs_dir_iops; inode->i_fop = &hppfs_dir_fops; - } else if (S_ISLNK(dentry->d_inode->i_mode)) { + } else if (d_is_symlink(dentry)) { inode->i_op = &hppfs_link_iops; inode->i_fop = &hppfs_file_fops; } else { diff --git a/fs/internal.h b/fs/internal.h index 30459da..01dce1d 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -84,7 +84,7 @@ extern struct file *get_empty_filp(void); * super.c */ extern int do_remount_sb(struct super_block *, int, void *, int); -extern bool grab_super_passive(struct super_block *sb); +extern bool trylock_super(struct super_block *sb); extern struct dentry *mount_fs(struct file_system_type *, int, const char *, void *); extern struct super_block *user_get_super(dev_t); diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c index 9385560..f21b6fb 100644 --- a/fs/jffs2/dir.c +++ b/fs/jffs2/dir.c @@ -252,7 +252,7 @@ static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct de if (!f->inocache) return -EIO; - if (S_ISDIR(old_dentry->d_inode->i_mode)) + if (d_is_dir(old_dentry)) return -EPERM; /* XXX: This is ugly */ @@ -772,7 +772,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, */ if (new_dentry->d_inode) { victim_f = JFFS2_INODE_INFO(new_dentry->d_inode); - if (S_ISDIR(new_dentry->d_inode->i_mode)) { + if (d_is_dir(new_dentry)) { struct jffs2_full_dirent *fd; mutex_lock(&victim_f->sem); @@ -807,7 +807,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, if (victim_f) { /* There was a victim. Kill it off nicely */ - if (S_ISDIR(new_dentry->d_inode->i_mode)) + if (d_is_dir(new_dentry)) clear_nlink(new_dentry->d_inode); else drop_nlink(new_dentry->d_inode); @@ -815,7 +815,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, inode which didn't exist. */ if (victim_f->inocache) { mutex_lock(&victim_f->sem); - if (S_ISDIR(new_dentry->d_inode->i_mode)) + if (d_is_dir(new_dentry)) victim_f->inocache->pino_nlink = 0; else victim_f->inocache->pino_nlink--; @@ -825,7 +825,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, /* If it was a directory we moved, and there was no victim, increase i_nlink on its new parent */ - if (S_ISDIR(old_dentry->d_inode->i_mode) && !victim_f) + if (d_is_dir(old_dentry) && !victim_f) inc_nlink(new_dir_i); /* Unlink the original */ @@ -839,7 +839,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode); mutex_lock(&f->sem); inc_nlink(old_dentry->d_inode); - if (f->inocache && !S_ISDIR(old_dentry->d_inode->i_mode)) + if (f->inocache && !d_is_dir(old_dentry)) f->inocache->pino_nlink++; mutex_unlock(&f->sem); @@ -852,7 +852,7 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, return ret; } - if (S_ISDIR(old_dentry->d_inode->i_mode)) + if (d_is_dir(old_dentry)) drop_nlink(old_dir_i); new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now); diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c index 0918f0e..3d76f28 100644 --- a/fs/jffs2/super.c +++ b/fs/jffs2/super.c @@ -138,7 +138,7 @@ static struct dentry *jffs2_get_parent(struct dentry *child) struct jffs2_inode_info *f; uint32_t pino; - BUG_ON(!S_ISDIR(child->d_inode->i_mode)); + BUG_ON(!d_is_dir(child)); f = JFFS2_INODE_INFO(child->d_inode); @@ -329,7 +329,7 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct inode *inode = old_dentry->d_inode; - int they_are_dirs = S_ISDIR(old_dentry->d_inode->i_mode); + int they_are_dirs = d_is_dir(old_dentry); if (!simple_empty(new_dentry)) return -ENOTEMPTY; @@ -2814,7 +2814,7 @@ no_open: } else if (!dentry->d_inode) { goto out; } else if ((open_flag & O_TRUNC) && - S_ISREG(dentry->d_inode->i_mode)) { + d_is_reg(dentry)) { goto out; } /* will fail later, go on to get the right error */ diff --git a/fs/namespace.c b/fs/namespace.c index 72a286e..82ef140 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1907,8 +1907,8 @@ static int graft_tree(struct mount *mnt, struct mount *p, struct mountpoint *mp) if (mnt->mnt.mnt_sb->s_flags & MS_NOUSER) return -EINVAL; - if (S_ISDIR(mp->m_dentry->d_inode->i_mode) != - S_ISDIR(mnt->mnt.mnt_root->d_inode->i_mode)) + if (d_is_dir(mp->m_dentry) != + d_is_dir(mnt->mnt.mnt_root)) return -ENOTDIR; return attach_recursive_mnt(mnt, p, mp, NULL); @@ -2180,8 +2180,8 @@ static int do_move_mount(struct path *path, const char *old_name) if (!mnt_has_parent(old)) goto out1; - if (S_ISDIR(path->dentry->d_inode->i_mode) != - S_ISDIR(old_path.dentry->d_inode->i_mode)) + if (d_is_dir(path->dentry) != + d_is_dir(old_path.dentry)) goto out1; /* * Don't move a mount residing in a shared parent. @@ -2271,7 +2271,7 @@ static int do_add_mount(struct mount *newmnt, struct path *path, int mnt_flags) goto unlock; err = -EINVAL; - if (S_ISLNK(newmnt->mnt.mnt_root->d_inode->i_mode)) + if (d_is_symlink(newmnt->mnt.mnt_root)) goto unlock; newmnt->mnt.mnt_flags = mnt_flags; diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c index cc6a760..1c307f0 100644 --- a/fs/nfsd/nfs4recover.c +++ b/fs/nfsd/nfs4recover.c @@ -583,7 +583,7 @@ nfs4_reset_recoverydir(char *recdir) if (status) return status; status = -ENOTDIR; - if (S_ISDIR(path.dentry->d_inode->i_mode)) { + if (d_is_dir(path.dentry)) { strcpy(user_recovery_dirname, recdir); status = 0; } @@ -1426,7 +1426,7 @@ nfsd4_client_tracking_init(struct net *net) nn->client_tracking_ops = &nfsd4_legacy_tracking_ops; status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path); if (!status) { - status = S_ISDIR(path.dentry->d_inode->i_mode); + status = d_is_dir(path.dentry); path_put(&path); if (status) goto do_init; diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index 965b478..e9fa966 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -114,8 +114,8 @@ static inline __be32 check_pseudo_root(struct svc_rqst *rqstp, * We're exposing only the directories and symlinks that have to be * traversed on the way to real exports: */ - if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) && - !S_ISLNK(dentry->d_inode->i_mode))) + if (unlikely(!d_is_dir(dentry) && + !d_is_symlink(dentry))) return nfserr_stale; /* * A pseudoroot export gives permission to access only one @@ -259,7 +259,7 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) goto out; } - if (S_ISDIR(dentry->d_inode->i_mode) && + if (d_is_dir(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED)) { printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n", dentry); @@ -414,7 +414,7 @@ static inline void _fh_update_old(struct dentry *dentry, { fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino); fh->ofh_generation = dentry->d_inode->i_generation; - if (S_ISDIR(dentry->d_inode->i_mode) || + if (d_is_dir(dentry) || (exp->ex_flags & NFSEXP_NOSUBTREECHECK)) fh->ofh_dirino = 0; } diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 5685c67..3685265 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -615,9 +615,9 @@ nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *suppor export = fhp->fh_export; dentry = fhp->fh_dentry; - if (S_ISREG(dentry->d_inode->i_mode)) + if (d_is_reg(dentry)) map = nfs3_regaccess; - else if (S_ISDIR(dentry->d_inode->i_mode)) + else if (d_is_dir(dentry)) map = nfs3_diraccess; else map = nfs3_anyaccess; @@ -1402,7 +1402,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, switch (createmode) { case NFS3_CREATE_UNCHECKED: - if (! S_ISREG(dchild->d_inode->i_mode)) + if (! d_is_reg(dchild)) goto out; else if (truncp) { /* in nfsv4, we need to treat this case a little @@ -1615,7 +1615,7 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp, if (err) goto out; err = nfserr_isdir; - if (S_ISDIR(tfhp->fh_dentry->d_inode->i_mode)) + if (d_is_dir(tfhp->fh_dentry)) goto out; err = nfserr_perm; if (!len) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 51ceb81..9a66ff7 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -115,8 +115,8 @@ static bool fanotify_should_send_event(struct fsnotify_mark *inode_mark, return false; /* sorry, fanotify only gives a damn about files and dirs */ - if (!S_ISREG(path->dentry->d_inode->i_mode) && - !S_ISDIR(path->dentry->d_inode->i_mode)) + if (!d_is_reg(path->dentry) && + !d_can_lookup(path->dentry)) return false; if (inode_mark && vfsmnt_mark) { @@ -139,7 +139,7 @@ static bool fanotify_should_send_event(struct fsnotify_mark *inode_mark, BUG(); } - if (S_ISDIR(path->dentry->d_inode->i_mode) && + if (d_is_dir(path->dentry) && !(marks_mask & FS_ISDIR & ~marks_ignored_mask)) return false; diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index ea10a87..24f6404 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -191,7 +191,6 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat) ovl_set_timestamps(upperdentry, stat); return err; - } static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir, @@ -385,7 +384,7 @@ int ovl_copy_up(struct dentry *dentry) struct kstat stat; enum ovl_path_type type = ovl_path_type(dentry); - if (type != OVL_PATH_LOWER) + if (OVL_TYPE_UPPER(type)) break; next = dget(dentry); @@ -394,7 +393,7 @@ int ovl_copy_up(struct dentry *dentry) parent = dget_parent(next); type = ovl_path_type(parent); - if (type != OVL_PATH_LOWER) + if (OVL_TYPE_UPPER(type)) break; dput(next); diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 8ffc4b9..d139405 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -19,7 +19,7 @@ void ovl_cleanup(struct inode *wdir, struct dentry *wdentry) int err; dget(wdentry); - if (S_ISDIR(wdentry->d_inode->i_mode)) + if (d_is_dir(wdentry)) err = ovl_do_rmdir(wdir, wdentry); else err = ovl_do_unlink(wdir, wdentry); @@ -118,14 +118,14 @@ int ovl_create_real(struct inode *dir, struct dentry *newdentry, static int ovl_set_opaque(struct dentry *upperdentry) { - return ovl_do_setxattr(upperdentry, ovl_opaque_xattr, "y", 1, 0); + return ovl_do_setxattr(upperdentry, OVL_XATTR_OPAQUE, "y", 1, 0); } static void ovl_remove_opaque(struct dentry *upperdentry) { int err; - err = ovl_do_removexattr(upperdentry, ovl_opaque_xattr); + err = ovl_do_removexattr(upperdentry, OVL_XATTR_OPAQUE); if (err) { pr_warn("overlayfs: failed to remove opaque from '%s' (%i)\n", upperdentry->d_name.name, err); @@ -152,7 +152,7 @@ static int ovl_dir_getattr(struct vfsmount *mnt, struct dentry *dentry, * correct link count. nlink=1 seems to pacify 'find' and * other utilities. */ - if (type == OVL_PATH_MERGE) + if (OVL_TYPE_MERGE(type)) stat->nlink = 1; return 0; @@ -506,7 +506,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) struct dentry *opaquedir = NULL; int err; - if (is_dir) { + if (is_dir && OVL_TYPE_MERGE_OR_LOWER(ovl_path_type(dentry))) { opaquedir = ovl_check_empty_and_clear(dentry); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) @@ -630,7 +630,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) goto out_drop_write; type = ovl_path_type(dentry); - if (type == OVL_PATH_PURE_UPPER) { + if (OVL_TYPE_PURE_UPPER(type)) { err = ovl_remove_upper(dentry, is_dir); } else { const struct cred *old_cred; @@ -693,7 +693,7 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, bool new_create = false; bool cleanup_whiteout = false; bool overwrite = !(flags & RENAME_EXCHANGE); - bool is_dir = S_ISDIR(old->d_inode->i_mode); + bool is_dir = d_is_dir(old); bool new_is_dir = false; struct dentry *opaquedir = NULL; const struct cred *old_cred = NULL; @@ -712,7 +712,7 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, /* Don't copy up directory trees */ old_type = ovl_path_type(old); err = -EXDEV; - if ((old_type == OVL_PATH_LOWER || old_type == OVL_PATH_MERGE) && is_dir) + if (OVL_TYPE_MERGE_OR_LOWER(old_type) && is_dir) goto out; if (new->d_inode) { @@ -720,30 +720,30 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, if (err) goto out; - if (S_ISDIR(new->d_inode->i_mode)) + if (d_is_dir(new)) new_is_dir = true; new_type = ovl_path_type(new); err = -EXDEV; - if (!overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) + if (!overwrite && OVL_TYPE_MERGE_OR_LOWER(new_type) && new_is_dir) goto out; err = 0; - if (new_type == OVL_PATH_LOWER && old_type == OVL_PATH_LOWER) { + if (!OVL_TYPE_UPPER(new_type) && !OVL_TYPE_UPPER(old_type)) { if (ovl_dentry_lower(old)->d_inode == ovl_dentry_lower(new)->d_inode) goto out; } - if (new_type != OVL_PATH_LOWER && old_type != OVL_PATH_LOWER) { + if (OVL_TYPE_UPPER(new_type) && OVL_TYPE_UPPER(old_type)) { if (ovl_dentry_upper(old)->d_inode == ovl_dentry_upper(new)->d_inode) goto out; } } else { if (ovl_dentry_is_opaque(new)) - new_type = OVL_PATH_UPPER; + new_type = __OVL_PATH_UPPER; else - new_type = OVL_PATH_PURE_UPPER; + new_type = __OVL_PATH_UPPER | __OVL_PATH_PURE; } err = ovl_want_write(old); @@ -763,8 +763,8 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, goto out_drop_write; } - old_opaque = old_type != OVL_PATH_PURE_UPPER; - new_opaque = new_type != OVL_PATH_PURE_UPPER; + old_opaque = !OVL_TYPE_PURE_UPPER(old_type); + new_opaque = !OVL_TYPE_PURE_UPPER(new_type); if (old_opaque || new_opaque) { err = -ENOMEM; @@ -787,7 +787,7 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, old_cred = override_creds(override_cred); } - if (overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) { + if (overwrite && OVL_TYPE_MERGE_OR_LOWER(new_type) && new_is_dir) { opaquedir = ovl_check_empty_and_clear(new); err = PTR_ERR(opaquedir); if (IS_ERR(opaquedir)) { diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 07d74b2..04f1248 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -205,7 +205,7 @@ static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz) static bool ovl_is_private_xattr(const char *name) { - return strncmp(name, "trusted.overlay.", 14) == 0; + return strncmp(name, OVL_XATTR_PRE_NAME, OVL_XATTR_PRE_LEN) == 0; } int ovl_setxattr(struct dentry *dentry, const char *name, @@ -238,7 +238,10 @@ out: static bool ovl_need_xattr_filter(struct dentry *dentry, enum ovl_path_type type) { - return type == OVL_PATH_UPPER && S_ISDIR(dentry->d_inode->i_mode); + if ((type & (__OVL_PATH_PURE | __OVL_PATH_UPPER)) == __OVL_PATH_UPPER) + return S_ISDIR(dentry->d_inode->i_mode); + else + return false; } ssize_t ovl_getxattr(struct dentry *dentry, const char *name, @@ -299,7 +302,7 @@ int ovl_removexattr(struct dentry *dentry, const char *name) if (ovl_need_xattr_filter(dentry, type) && ovl_is_private_xattr(name)) goto out_drop_write; - if (type == OVL_PATH_LOWER) { + if (!OVL_TYPE_UPPER(type)) { err = vfs_getxattr(realpath.dentry, name, NULL, 0); if (err < 0) goto out_drop_write; @@ -321,7 +324,7 @@ out: static bool ovl_open_need_copy_up(int flags, enum ovl_path_type type, struct dentry *realdentry) { - if (type != OVL_PATH_LOWER) + if (OVL_TYPE_UPPER(type)) return false; if (special_file(realdentry->d_inode->i_mode)) @@ -430,5 +433,4 @@ struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, } return inode; - } diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 814bed3..17ac5af 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -12,13 +12,20 @@ struct ovl_entry; enum ovl_path_type { - OVL_PATH_PURE_UPPER, - OVL_PATH_UPPER, - OVL_PATH_MERGE, - OVL_PATH_LOWER, + __OVL_PATH_PURE = (1 << 0), + __OVL_PATH_UPPER = (1 << 1), + __OVL_PATH_MERGE = (1 << 2), }; -extern const char *ovl_opaque_xattr; +#define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER) +#define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE) +#define OVL_TYPE_PURE_UPPER(type) ((type) & __OVL_PATH_PURE) +#define OVL_TYPE_MERGE_OR_LOWER(type) \ + (OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type)) + +#define OVL_XATTR_PRE_NAME "trusted.overlay." +#define OVL_XATTR_PRE_LEN 16 +#define OVL_XATTR_OPAQUE OVL_XATTR_PRE_NAME"opaque" static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry) { @@ -130,6 +137,7 @@ void ovl_dentry_version_inc(struct dentry *dentry); void ovl_path_upper(struct dentry *dentry, struct path *path); void ovl_path_lower(struct dentry *dentry, struct path *path); enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path); +int ovl_path_next(int idx, struct dentry *dentry, struct path *path); struct dentry *ovl_dentry_upper(struct dentry *dentry); struct dentry *ovl_dentry_lower(struct dentry *dentry); struct dentry *ovl_dentry_real(struct dentry *dentry); diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index c020599..907870e 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -24,7 +24,6 @@ struct ovl_cache_entry { struct list_head l_node; struct rb_node node; bool is_whiteout; - bool is_cursor; char name[]; }; @@ -40,6 +39,7 @@ struct ovl_readdir_data { struct rb_root root; struct list_head *list; struct list_head middle; + struct dentry *dir; int count; int err; }; @@ -48,7 +48,7 @@ struct ovl_dir_file { bool is_real; bool is_upper; struct ovl_dir_cache *cache; - struct ovl_cache_entry cursor; + struct list_head *cursor; struct file *realfile; struct file *upperfile; }; @@ -79,23 +79,49 @@ static struct ovl_cache_entry *ovl_cache_entry_find(struct rb_root *root, return NULL; } -static struct ovl_cache_entry *ovl_cache_entry_new(const char *name, int len, +static struct ovl_cache_entry *ovl_cache_entry_new(struct dentry *dir, + const char *name, int len, u64 ino, unsigned int d_type) { struct ovl_cache_entry *p; size_t size = offsetof(struct ovl_cache_entry, name[len + 1]); p = kmalloc(size, GFP_KERNEL); - if (p) { - memcpy(p->name, name, len); - p->name[len] = '\0'; - p->len = len; - p->type = d_type; - p->ino = ino; - p->is_whiteout = false; - p->is_cursor = false; - } + if (!p) + return NULL; + + memcpy(p->name, name, len); + p->name[len] = '\0'; + p->len = len; + p->type = d_type; + p->ino = ino; + p->is_whiteout = false; + + if (d_type == DT_CHR) { + struct dentry *dentry; + const struct cred *old_cred; + struct cred *override_cred; + + override_cred = prepare_creds(); + if (!override_cred) { + kfree(p); + return NULL; + } + + /* + * CAP_DAC_OVERRIDE for lookup + */ + cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE); + old_cred = override_creds(override_cred); + dentry = lookup_one_len(name, dir, len); + if (!IS_ERR(dentry)) { + p->is_whiteout = ovl_is_whiteout(dentry); + dput(dentry); + } + revert_creds(old_cred); + put_cred(override_cred); + } return p; } @@ -122,7 +148,7 @@ static int ovl_cache_entry_add_rb(struct ovl_readdir_data *rdd, return 0; } - p = ovl_cache_entry_new(name, len, ino, d_type); + p = ovl_cache_entry_new(rdd->dir, name, len, ino, d_type); if (p == NULL) return -ENOMEM; @@ -143,7 +169,7 @@ static int ovl_fill_lower(struct ovl_readdir_data *rdd, if (p) { list_move_tail(&p->l_node, &rdd->middle); } else { - p = ovl_cache_entry_new(name, namelen, ino, d_type); + p = ovl_cache_entry_new(rdd->dir, name, namelen, ino, d_type); if (p == NULL) rdd->err = -ENOMEM; else @@ -168,7 +194,6 @@ static void ovl_cache_put(struct ovl_dir_file *od, struct dentry *dentry) { struct ovl_dir_cache *cache = od->cache; - list_del_init(&od->cursor.l_node); WARN_ON(cache->refcount <= 0); cache->refcount--; if (!cache->refcount) { @@ -204,6 +229,7 @@ static inline int ovl_dir_read(struct path *realpath, if (IS_ERR(realfile)) return PTR_ERR(realfile); + rdd->dir = realpath->dentry; rdd->ctx.pos = 0; do { rdd->count = 0; @@ -227,108 +253,58 @@ static void ovl_dir_reset(struct file *file) if (cache && ovl_dentry_version_get(dentry) != cache->version) { ovl_cache_put(od, dentry); od->cache = NULL; + od->cursor = NULL; } - WARN_ON(!od->is_real && type != OVL_PATH_MERGE); - if (od->is_real && type == OVL_PATH_MERGE) + WARN_ON(!od->is_real && !OVL_TYPE_MERGE(type)); + if (od->is_real && OVL_TYPE_MERGE(type)) od->is_real = false; } -static int ovl_dir_mark_whiteouts(struct dentry *dir, - struct ovl_readdir_data *rdd) -{ - struct ovl_cache_entry *p; - struct dentry *dentry; - const struct cred *old_cred; - struct cred *override_cred; - - override_cred = prepare_creds(); - if (!override_cred) { - ovl_cache_free(rdd->list); - return -ENOMEM; - } - - /* - * CAP_DAC_OVERRIDE for lookup - */ - cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE); - old_cred = override_creds(override_cred); - - mutex_lock(&dir->d_inode->i_mutex); - list_for_each_entry(p, rdd->list, l_node) { - if (p->is_cursor) - continue; - - if (p->type != DT_CHR) - continue; - - dentry = lookup_one_len(p->name, dir, p->len); - if (IS_ERR(dentry)) - continue; - - p->is_whiteout = ovl_is_whiteout(dentry); - dput(dentry); - } - mutex_unlock(&dir->d_inode->i_mutex); - - revert_creds(old_cred); - put_cred(override_cred); - - return 0; -} - static int ovl_dir_read_merged(struct dentry *dentry, struct list_head *list) { int err; - struct path lowerpath; - struct path upperpath; + struct path realpath; struct ovl_readdir_data rdd = { .ctx.actor = ovl_fill_merge, .list = list, .root = RB_ROOT, .is_merge = false, }; + int idx, next; - ovl_path_lower(dentry, &lowerpath); - ovl_path_upper(dentry, &upperpath); + for (idx = 0; idx != -1; idx = next) { + next = ovl_path_next(idx, dentry, &realpath); - if (upperpath.dentry) { - err = ovl_dir_read(&upperpath, &rdd); - if (err) - goto out; - - if (lowerpath.dentry) { - err = ovl_dir_mark_whiteouts(upperpath.dentry, &rdd); + if (next != -1) { + err = ovl_dir_read(&realpath, &rdd); if (err) - goto out; + break; + } else { + /* + * Insert lowest layer entries before upper ones, this + * allows offsets to be reasonably constant + */ + list_add(&rdd.middle, rdd.list); + rdd.is_merge = true; + err = ovl_dir_read(&realpath, &rdd); + list_del(&rdd.middle); } } - if (lowerpath.dentry) { - /* - * Insert lowerpath entries before upperpath ones, this allows - * offsets to be reasonably constant - */ - list_add(&rdd.middle, rdd.list); - rdd.is_merge = true; - err = ovl_dir_read(&lowerpath, &rdd); - list_del(&rdd.middle); - } -out: return err; } static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos) { - struct ovl_cache_entry *p; + struct list_head *p; loff_t off = 0; - list_for_each_entry(p, &od->cache->entries, l_node) { - if (p->is_cursor) - continue; + list_for_each(p, &od->cache->entries) { if (off >= pos) break; off++; } - list_move_tail(&od->cursor.l_node, &p->l_node); + /* Cursor is safe since the cache is stable */ + od->cursor = p; } static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry) @@ -367,6 +343,7 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx) { struct ovl_dir_file *od = file->private_data; struct dentry *dentry = file->f_path.dentry; + struct ovl_cache_entry *p; if (!ctx->pos) ovl_dir_reset(file); @@ -385,19 +362,13 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx) ovl_seek_cursor(od, ctx->pos); } - while (od->cursor.l_node.next != &od->cache->entries) { - struct ovl_cache_entry *p; - - p = list_entry(od->cursor.l_node.next, struct ovl_cache_entry, l_node); - /* Skip cursors */ - if (!p->is_cursor) { - if (!p->is_whiteout) { - if (!dir_emit(ctx, p->name, p->len, p->ino, p->type)) - break; - } - ctx->pos++; - } - list_move(&od->cursor.l_node, &p->l_node); + while (od->cursor != &od->cache->entries) { + p = list_entry(od->cursor, struct ovl_cache_entry, l_node); + if (!p->is_whiteout) + if (!dir_emit(ctx, p->name, p->len, p->ino, p->type)) + break; + od->cursor = p->l_node.next; + ctx->pos++; } return 0; } @@ -452,7 +423,7 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, /* * Need to check if we started out being a lower dir, but got copied up */ - if (!od->is_upper && ovl_path_type(dentry) != OVL_PATH_LOWER) { + if (!od->is_upper && OVL_TYPE_UPPER(ovl_path_type(dentry))) { struct inode *inode = file_inode(file); realfile = lockless_dereference(od->upperfile); @@ -516,11 +487,9 @@ static int ovl_dir_open(struct inode *inode, struct file *file) kfree(od); return PTR_ERR(realfile); } - INIT_LIST_HEAD(&od->cursor.l_node); od->realfile = realfile; - od->is_real = (type != OVL_PATH_MERGE); - od->is_upper = (type != OVL_PATH_LOWER); - od->cursor.is_cursor = true; + od->is_real = !OVL_TYPE_MERGE(type); + od->is_upper = OVL_TYPE_UPPER(type); file->private_data = od; return 0; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index f16d318..b90952f 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -35,7 +35,8 @@ struct ovl_config { /* private information held for overlayfs's superblock */ struct ovl_fs { struct vfsmount *upper_mnt; - struct vfsmount *lower_mnt; + unsigned numlower; + struct vfsmount **lower_mnt; struct dentry *workdir; long lower_namelen; /* pathnames of lower and upper dirs, for show_options */ @@ -47,7 +48,6 @@ struct ovl_dir_cache; /* private information held for every overlayfs dentry */ struct ovl_entry { struct dentry *__upperdentry; - struct dentry *lowerdentry; struct ovl_dir_cache *cache; union { struct { @@ -56,30 +56,36 @@ struct ovl_entry { }; struct rcu_head rcu; }; + unsigned numlower; + struct path lowerstack[]; }; -const char *ovl_opaque_xattr = "trusted.overlay.opaque"; +#define OVL_MAX_STACK 500 +static struct dentry *__ovl_dentry_lower(struct ovl_entry *oe) +{ + return oe->numlower ? oe->lowerstack[0].dentry : NULL; +} enum ovl_path_type ovl_path_type(struct dentry *dentry) { struct ovl_entry *oe = dentry->d_fsdata; + enum ovl_path_type type = 0; if (oe->__upperdentry) { - if (oe->lowerdentry) { + type = __OVL_PATH_UPPER; + + if (oe->numlower) { if (S_ISDIR(dentry->d_inode->i_mode)) - return OVL_PATH_MERGE; - else - return OVL_PATH_UPPER; - } else { - if (oe->opaque) - return OVL_PATH_UPPER; - else - return OVL_PATH_PURE_UPPER; + type |= __OVL_PATH_MERGE; + } else if (!oe->opaque) { + type |= __OVL_PATH_PURE; } } else { - return OVL_PATH_LOWER; + if (oe->numlower > 1) + type |= __OVL_PATH_MERGE; } + return type; } static struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe) @@ -98,10 +104,9 @@ void ovl_path_upper(struct dentry *dentry, struct path *path) enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path) { - enum ovl_path_type type = ovl_path_type(dentry); - if (type == OVL_PATH_LOWER) + if (!OVL_TYPE_UPPER(type)) ovl_path_lower(dentry, path); else ovl_path_upper(dentry, path); @@ -120,7 +125,7 @@ struct dentry *ovl_dentry_lower(struct dentry *dentry) { struct ovl_entry *oe = dentry->d_fsdata; - return oe->lowerdentry; + return __ovl_dentry_lower(oe); } struct dentry *ovl_dentry_real(struct dentry *dentry) @@ -130,7 +135,7 @@ struct dentry *ovl_dentry_real(struct dentry *dentry) realdentry = ovl_upperdentry_dereference(oe); if (!realdentry) - realdentry = oe->lowerdentry; + realdentry = __ovl_dentry_lower(oe); return realdentry; } @@ -143,7 +148,7 @@ struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper) if (realdentry) { *is_upper = true; } else { - realdentry = oe->lowerdentry; + realdentry = __ovl_dentry_lower(oe); *is_upper = false; } return realdentry; @@ -165,11 +170,9 @@ void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache) void ovl_path_lower(struct dentry *dentry, struct path *path) { - struct ovl_fs *ofs = dentry->d_sb->s_fs_info; struct ovl_entry *oe = dentry->d_fsdata; - path->mnt = ofs->lower_mnt; - path->dentry = oe->lowerdentry; + *path = oe->numlower ? oe->lowerstack[0] : (struct path) { NULL, NULL }; } int ovl_want_write(struct dentry *dentry) @@ -249,7 +252,7 @@ static bool ovl_is_opaquedir(struct dentry *dentry) if (!S_ISDIR(inode->i_mode) || !inode->i_op->getxattr) return false; - res = inode->i_op->getxattr(dentry, ovl_opaque_xattr, &val, 1); + res = inode->i_op->getxattr(dentry, OVL_XATTR_OPAQUE, &val, 1); if (res == 1 && val == 'y') return true; @@ -261,8 +264,11 @@ static void ovl_dentry_release(struct dentry *dentry) struct ovl_entry *oe = dentry->d_fsdata; if (oe) { + unsigned int i; + dput(oe->__upperdentry); - dput(oe->lowerdentry); + for (i = 0; i < oe->numlower; i++) + dput(oe->lowerstack[i].dentry); kfree_rcu(oe, rcu); } } @@ -271,9 +277,15 @@ static const struct dentry_operations ovl_dentry_operations = { .d_release = ovl_dentry_release, }; -static struct ovl_entry *ovl_alloc_entry(void) +static struct ovl_entry *ovl_alloc_entry(unsigned int numlower) { - return kzalloc(sizeof(struct ovl_entry), GFP_KERNEL); + size_t size = offsetof(struct ovl_entry, lowerstack[numlower]); + struct ovl_entry *oe = kzalloc(size, GFP_KERNEL); + + if (oe) + oe->numlower = numlower; + + return oe; } static inline struct dentry *ovl_lookup_real(struct dentry *dir, @@ -295,82 +307,154 @@ static inline struct dentry *ovl_lookup_real(struct dentry *dir, return dentry; } +/* + * Returns next layer in stack starting from top. + * Returns -1 if this is the last layer. + */ +int ovl_path_next(int idx, struct dentry *dentry, struct path *path) +{ + struct ovl_entry *oe = dentry->d_fsdata; + + BUG_ON(idx < 0); + if (idx == 0) { + ovl_path_upper(dentry, path); + if (path->dentry) + return oe->numlower ? 1 : -1; + idx++; + } + BUG_ON(idx > oe->numlower); + *path = oe->lowerstack[idx - 1]; + + return (idx < oe->numlower) ? idx + 1 : -1; +} + struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct ovl_entry *oe; - struct dentry *upperdir; - struct dentry *lowerdir; - struct dentry *upperdentry = NULL; - struct dentry *lowerdentry = NULL; + struct ovl_entry *poe = dentry->d_parent->d_fsdata; + struct path *stack = NULL; + struct dentry *upperdir, *upperdentry = NULL; + unsigned int ctr = 0; struct inode *inode = NULL; + bool upperopaque = false; + struct dentry *this, *prev = NULL; + unsigned int i; int err; - err = -ENOMEM; - oe = ovl_alloc_entry(); - if (!oe) - goto out; - - upperdir = ovl_dentry_upper(dentry->d_parent); - lowerdir = ovl_dentry_lower(dentry->d_parent); - + upperdir = ovl_upperdentry_dereference(poe); if (upperdir) { - upperdentry = ovl_lookup_real(upperdir, &dentry->d_name); - err = PTR_ERR(upperdentry); - if (IS_ERR(upperdentry)) - goto out_put_dir; - - if (lowerdir && upperdentry) { - if (ovl_is_whiteout(upperdentry)) { - dput(upperdentry); - upperdentry = NULL; - oe->opaque = true; - } else if (ovl_is_opaquedir(upperdentry)) { - oe->opaque = true; + this = ovl_lookup_real(upperdir, &dentry->d_name); + err = PTR_ERR(this); + if (IS_ERR(this)) + goto out; + + if (this) { + if (ovl_is_whiteout(this)) { + dput(this); + this = NULL; + upperopaque = true; + } else if (poe->numlower && ovl_is_opaquedir(this)) { + upperopaque = true; } } + upperdentry = prev = this; } - if (lowerdir && !oe->opaque) { - lowerdentry = ovl_lookup_real(lowerdir, &dentry->d_name); - err = PTR_ERR(lowerdentry); - if (IS_ERR(lowerdentry)) - goto out_dput_upper; + + if (!upperopaque && poe->numlower) { + err = -ENOMEM; + stack = kcalloc(poe->numlower, sizeof(struct path), GFP_KERNEL); + if (!stack) + goto out_put_upper; } - if (lowerdentry && upperdentry && - (!S_ISDIR(upperdentry->d_inode->i_mode) || - !S_ISDIR(lowerdentry->d_inode->i_mode))) { - dput(lowerdentry); - lowerdentry = NULL; - oe->opaque = true; + for (i = 0; !upperopaque && i < poe->numlower; i++) { + bool opaque = false; + struct path lowerpath = poe->lowerstack[i]; + + this = ovl_lookup_real(lowerpath.dentry, &dentry->d_name); + err = PTR_ERR(this); + if (IS_ERR(this)) { + /* + * If it's positive, then treat ENAMETOOLONG as ENOENT. + */ + if (err == -ENAMETOOLONG && (upperdentry || ctr)) + continue; + goto out_put; + } + if (!this) + continue; + if (ovl_is_whiteout(this)) { + dput(this); + break; + } + /* + * Only makes sense to check opaque dir if this is not the + * lowermost layer. + */ + if (i < poe->numlower - 1 && ovl_is_opaquedir(this)) + opaque = true; + + if (prev && (!S_ISDIR(prev->d_inode->i_mode) || + !S_ISDIR(this->d_inode->i_mode))) { + /* + * FIXME: check for upper-opaqueness maybe better done + * in remove code. + */ + if (prev == upperdentry) + upperopaque = true; + dput(this); + break; + } + /* + * If this is a non-directory then stop here. + */ + if (!S_ISDIR(this->d_inode->i_mode)) + opaque = true; + + stack[ctr].dentry = this; + stack[ctr].mnt = lowerpath.mnt; + ctr++; + prev = this; + if (opaque) + break; } - if (lowerdentry || upperdentry) { + oe = ovl_alloc_entry(ctr); + err = -ENOMEM; + if (!oe) + goto out_put; + + if (upperdentry || ctr) { struct dentry *realdentry; - realdentry = upperdentry ? upperdentry : lowerdentry; + realdentry = upperdentry ? upperdentry : stack[0].dentry; + err = -ENOMEM; inode = ovl_new_inode(dentry->d_sb, realdentry->d_inode->i_mode, oe); if (!inode) - goto out_dput; + goto out_free_oe; ovl_copyattr(realdentry->d_inode, inode); } + oe->opaque = upperopaque; oe->__upperdentry = upperdentry; - oe->lowerdentry = lowerdentry; - + memcpy(oe->lowerstack, stack, sizeof(struct path) * ctr); + kfree(stack); dentry->d_fsdata = oe; d_add(dentry, inode); return NULL; -out_dput: - dput(lowerdentry); -out_dput_upper: - dput(upperdentry); -out_put_dir: +out_free_oe: kfree(oe); +out_put: + for (i = 0; i < ctr; i++) + dput(stack[i].dentry); + kfree(stack); +out_put_upper: + dput(upperdentry); out: return ERR_PTR(err); } @@ -383,10 +467,12 @@ struct file *ovl_path_open(struct path *path, int flags) static void ovl_put_super(struct super_block *sb) { struct ovl_fs *ufs = sb->s_fs_info; + unsigned i; dput(ufs->workdir); mntput(ufs->upper_mnt); - mntput(ufs->lower_mnt); + for (i = 0; i < ufs->numlower; i++) + mntput(ufs->lower_mnt[i]); kfree(ufs->config.lowerdir); kfree(ufs->config.upperdir); @@ -400,7 +486,7 @@ static void ovl_put_super(struct super_block *sb) * @buf: The struct kstatfs to fill in with stats * * Get the filesystem statistics. As writes always target the upper layer - * filesystem pass the statfs to the same filesystem. + * filesystem pass the statfs to the upper filesystem (if it exists) */ static int ovl_statfs(struct dentry *dentry, struct kstatfs *buf) { @@ -409,7 +495,7 @@ static int ovl_statfs(struct dentry *dentry, struct kstatfs *buf) struct path path; int err; - ovl_path_upper(root_dentry, &path); + ovl_path_real(root_dentry, &path); err = vfs_statfs(&path, buf); if (!err) { @@ -432,8 +518,21 @@ static int ovl_show_options(struct seq_file *m, struct dentry *dentry) struct ovl_fs *ufs = sb->s_fs_info; seq_printf(m, ",lowerdir=%s", ufs->config.lowerdir); - seq_printf(m, ",upperdir=%s", ufs->config.upperdir); - seq_printf(m, ",workdir=%s", ufs->config.workdir); + if (ufs->config.upperdir) { + seq_printf(m, ",upperdir=%s", ufs->config.upperdir); + seq_printf(m, ",workdir=%s", ufs->config.workdir); + } + return 0; +} + +static int ovl_remount(struct super_block *sb, int *flags, char *data) +{ + struct ovl_fs *ufs = sb->s_fs_info; + + if (!(*flags & MS_RDONLY) && + (!ufs->upper_mnt || (ufs->upper_mnt->mnt_sb->s_flags & MS_RDONLY))) + return -EROFS; + return 0; } @@ -441,6 +540,7 @@ static const struct super_operations ovl_super_operations = { .put_super = ovl_put_super, .statfs = ovl_statfs, .show_options = ovl_show_options, + .remount_fs = ovl_remount, }; enum { @@ -585,24 +685,6 @@ static void ovl_unescape(char *s) } } -static int ovl_mount_dir(const char *name, struct path *path) -{ - int err; - char *tmp = kstrdup(name, GFP_KERNEL); - - if (!tmp) - return -ENOMEM; - - ovl_unescape(tmp); - err = kern_path(tmp, LOOKUP_FOLLOW, path); - if (err) { - pr_err("overlayfs: failed to resolve '%s': %i\n", tmp, err); - err = -EINVAL; - } - kfree(tmp); - return err; -} - static bool ovl_is_allowed_fs_type(struct dentry *root) { const struct dentry_operations *dop = root->d_op; @@ -622,6 +704,75 @@ static bool ovl_is_allowed_fs_type(struct dentry *root) return true; } +static int ovl_mount_dir_noesc(const char *name, struct path *path) +{ + int err = -EINVAL; + + if (!*name) { + pr_err("overlayfs: empty lowerdir\n"); + goto out; + } + err = kern_path(name, LOOKUP_FOLLOW, path); + if (err) { + pr_err("overlayfs: failed to resolve '%s': %i\n", name, err); + goto out; + } + err = -EINVAL; + if (!ovl_is_allowed_fs_type(path->dentry)) { + pr_err("overlayfs: filesystem on '%s' not supported\n", name); + goto out_put; + } + if (!S_ISDIR(path->dentry->d_inode->i_mode)) { + pr_err("overlayfs: '%s' not a directory\n", name); + goto out_put; + } + return 0; + +out_put: + path_put(path); +out: + return err; +} + +static int ovl_mount_dir(const char *name, struct path *path) +{ + int err = -ENOMEM; + char *tmp = kstrdup(name, GFP_KERNEL); + + if (tmp) { + ovl_unescape(tmp); + err = ovl_mount_dir_noesc(tmp, path); + kfree(tmp); + } + return err; +} + +static int ovl_lower_dir(const char *name, struct path *path, long *namelen, + int *stack_depth) +{ + int err; + struct kstatfs statfs; + + err = ovl_mount_dir_noesc(name, path); + if (err) + goto out; + + err = vfs_statfs(path, &statfs); + if (err) { + pr_err("overlayfs: statfs failed on '%s'\n", name); + goto out_put; + } + *namelen = max(*namelen, statfs.f_namelen); + *stack_depth = max(*stack_depth, path->mnt->mnt_sb->s_stack_depth); + + return 0; + +out_put: + path_put(path); +out: + return err; +} + /* Workdir should not be subdir of upperdir and vice versa */ static bool ovl_workdir_ok(struct dentry *workdir, struct dentry *upperdir) { @@ -634,16 +785,39 @@ static bool ovl_workdir_ok(struct dentry *workdir, struct dentry *upperdir) return ok; } +static unsigned int ovl_split_lowerdirs(char *str) +{ + unsigned int ctr = 1; + char *s, *d; + + for (s = d = str;; s++, d++) { + if (*s == '\\') { + s++; + } else if (*s == ':') { + *d = '\0'; + ctr++; + continue; + } + *d = *s; + if (!*s) + break; + } + return ctr; +} + static int ovl_fill_super(struct super_block *sb, void *data, int silent) { - struct path lowerpath; - struct path upperpath; - struct path workpath; - struct inode *root_inode; + struct path upperpath = { NULL, NULL }; + struct path workpath = { NULL, NULL }; struct dentry *root_dentry; struct ovl_entry *oe; struct ovl_fs *ufs; - struct kstatfs statfs; + struct path *stack = NULL; + char *lowertmp; + char *lower; + unsigned int numlower; + unsigned int stacklen = 0; + unsigned int i; int err; err = -ENOMEM; @@ -655,123 +829,135 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) if (err) goto out_free_config; - /* FIXME: workdir is not needed for a R/O mount */ err = -EINVAL; - if (!ufs->config.upperdir || !ufs->config.lowerdir || - !ufs->config.workdir) { - pr_err("overlayfs: missing upperdir or lowerdir or workdir\n"); + if (!ufs->config.lowerdir) { + pr_err("overlayfs: missing 'lowerdir'\n"); goto out_free_config; } - err = -ENOMEM; - oe = ovl_alloc_entry(); - if (oe == NULL) - goto out_free_config; - - err = ovl_mount_dir(ufs->config.upperdir, &upperpath); - if (err) - goto out_free_oe; - - err = ovl_mount_dir(ufs->config.lowerdir, &lowerpath); - if (err) - goto out_put_upperpath; + sb->s_stack_depth = 0; + if (ufs->config.upperdir) { + /* FIXME: workdir is not needed for a R/O mount */ + if (!ufs->config.workdir) { + pr_err("overlayfs: missing 'workdir'\n"); + goto out_free_config; + } - err = ovl_mount_dir(ufs->config.workdir, &workpath); - if (err) - goto out_put_lowerpath; + err = ovl_mount_dir(ufs->config.upperdir, &upperpath); + if (err) + goto out_free_config; - err = -EINVAL; - if (!S_ISDIR(upperpath.dentry->d_inode->i_mode) || - !S_ISDIR(lowerpath.dentry->d_inode->i_mode) || - !S_ISDIR(workpath.dentry->d_inode->i_mode)) { - pr_err("overlayfs: upperdir or lowerdir or workdir not a directory\n"); - goto out_put_workpath; - } + err = ovl_mount_dir(ufs->config.workdir, &workpath); + if (err) + goto out_put_upperpath; - if (upperpath.mnt != workpath.mnt) { - pr_err("overlayfs: workdir and upperdir must reside under the same mount\n"); - goto out_put_workpath; - } - if (!ovl_workdir_ok(workpath.dentry, upperpath.dentry)) { - pr_err("overlayfs: workdir and upperdir must be separate subtrees\n"); - goto out_put_workpath; + err = -EINVAL; + if (upperpath.mnt != workpath.mnt) { + pr_err("overlayfs: workdir and upperdir must reside under the same mount\n"); + goto out_put_workpath; + } + if (!ovl_workdir_ok(workpath.dentry, upperpath.dentry)) { + pr_err("overlayfs: workdir and upperdir must be separate subtrees\n"); + goto out_put_workpath; + } + sb->s_stack_depth = upperpath.mnt->mnt_sb->s_stack_depth; } - - if (!ovl_is_allowed_fs_type(upperpath.dentry)) { - pr_err("overlayfs: filesystem of upperdir is not supported\n"); + err = -ENOMEM; + lowertmp = kstrdup(ufs->config.lowerdir, GFP_KERNEL); + if (!lowertmp) goto out_put_workpath; - } - if (!ovl_is_allowed_fs_type(lowerpath.dentry)) { - pr_err("overlayfs: filesystem of lowerdir is not supported\n"); - goto out_put_workpath; - } + err = -EINVAL; + stacklen = ovl_split_lowerdirs(lowertmp); + if (stacklen > OVL_MAX_STACK) + goto out_free_lowertmp; + + stack = kcalloc(stacklen, sizeof(struct path), GFP_KERNEL); + if (!stack) + goto out_free_lowertmp; + + lower = lowertmp; + for (numlower = 0; numlower < stacklen; numlower++) { + err = ovl_lower_dir(lower, &stack[numlower], + &ufs->lower_namelen, &sb->s_stack_depth); + if (err) + goto out_put_lowerpath; - err = vfs_statfs(&lowerpath, &statfs); - if (err) { - pr_err("overlayfs: statfs failed on lowerpath\n"); - goto out_put_workpath; + lower = strchr(lower, '\0') + 1; } - ufs->lower_namelen = statfs.f_namelen; - - sb->s_stack_depth = max(upperpath.mnt->mnt_sb->s_stack_depth, - lowerpath.mnt->mnt_sb->s_stack_depth) + 1; err = -EINVAL; + sb->s_stack_depth++; if (sb->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) { pr_err("overlayfs: maximum fs stacking depth exceeded\n"); - goto out_put_workpath; + goto out_put_lowerpath; } - ufs->upper_mnt = clone_private_mount(&upperpath); - err = PTR_ERR(ufs->upper_mnt); - if (IS_ERR(ufs->upper_mnt)) { - pr_err("overlayfs: failed to clone upperpath\n"); - goto out_put_workpath; - } + if (ufs->config.upperdir) { + ufs->upper_mnt = clone_private_mount(&upperpath); + err = PTR_ERR(ufs->upper_mnt); + if (IS_ERR(ufs->upper_mnt)) { + pr_err("overlayfs: failed to clone upperpath\n"); + goto out_put_lowerpath; + } - ufs->lower_mnt = clone_private_mount(&lowerpath); - err = PTR_ERR(ufs->lower_mnt); - if (IS_ERR(ufs->lower_mnt)) { - pr_err("overlayfs: failed to clone lowerpath\n"); - goto out_put_upper_mnt; + ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry); + err = PTR_ERR(ufs->workdir); + if (IS_ERR(ufs->workdir)) { + pr_err("overlayfs: failed to create directory %s/%s\n", + ufs->config.workdir, OVL_WORKDIR_NAME); + goto out_put_upper_mnt; + } } - ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry); - err = PTR_ERR(ufs->workdir); - if (IS_ERR(ufs->workdir)) { - pr_err("overlayfs: failed to create directory %s/%s\n", - ufs->config.workdir, OVL_WORKDIR_NAME); - goto out_put_lower_mnt; - } + err = -ENOMEM; + ufs->lower_mnt = kcalloc(numlower, sizeof(struct vfsmount *), GFP_KERNEL); + if (ufs->lower_mnt == NULL) + goto out_put_workdir; + for (i = 0; i < numlower; i++) { + struct vfsmount *mnt = clone_private_mount(&stack[i]); - /* - * Make lower_mnt R/O. That way fchmod/fchown on lower file - * will fail instead of modifying lower fs. - */ - ufs->lower_mnt->mnt_flags |= MNT_READONLY; + err = PTR_ERR(mnt); + if (IS_ERR(mnt)) { + pr_err("overlayfs: failed to clone lowerpath\n"); + goto out_put_lower_mnt; + } + /* + * Make lower_mnt R/O. That way fchmod/fchown on lower file + * will fail instead of modifying lower fs. + */ + mnt->mnt_flags |= MNT_READONLY; + + ufs->lower_mnt[ufs->numlower] = mnt; + ufs->numlower++; + } - /* If the upper fs is r/o, we mark overlayfs r/o too */ - if (ufs->upper_mnt->mnt_sb->s_flags & MS_RDONLY) + /* If the upper fs is r/o or nonexistent, we mark overlayfs r/o too */ + if (!ufs->upper_mnt || (ufs->upper_mnt->mnt_sb->s_flags & MS_RDONLY)) sb->s_flags |= MS_RDONLY; sb->s_d_op = &ovl_dentry_operations; err = -ENOMEM; - root_inode = ovl_new_inode(sb, S_IFDIR, oe); - if (!root_inode) - goto out_put_workdir; + oe = ovl_alloc_entry(numlower); + if (!oe) + goto out_put_lower_mnt; - root_dentry = d_make_root(root_inode); + root_dentry = d_make_root(ovl_new_inode(sb, S_IFDIR, oe)); if (!root_dentry) - goto out_put_workdir; + goto out_free_oe; mntput(upperpath.mnt); - mntput(lowerpath.mnt); + for (i = 0; i < numlower; i++) + mntput(stack[i].mnt); path_put(&workpath); + kfree(lowertmp); oe->__upperdentry = upperpath.dentry; - oe->lowerdentry = lowerpath.dentry; + for (i = 0; i < numlower; i++) { + oe->lowerstack[i].dentry = stack[i].dentry; + oe->lowerstack[i].mnt = ufs->lower_mnt[i]; + } root_dentry->d_fsdata = oe; @@ -782,20 +968,26 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) return 0; +out_free_oe: + kfree(oe); +out_put_lower_mnt: + for (i = 0; i < ufs->numlower; i++) + mntput(ufs->lower_mnt[i]); + kfree(ufs->lower_mnt); out_put_workdir: dput(ufs->workdir); -out_put_lower_mnt: - mntput(ufs->lower_mnt); out_put_upper_mnt: mntput(ufs->upper_mnt); +out_put_lowerpath: + for (i = 0; i < numlower; i++) + path_put(&stack[i]); + kfree(stack); +out_free_lowertmp: + kfree(lowertmp); out_put_workpath: path_put(&workpath); -out_put_lowerpath: - path_put(&lowerpath); out_put_upperpath: path_put(&upperpath); -out_free_oe: - kfree(oe); out_free_config: kfree(ufs->config.lowerdir); kfree(ufs->config.upperdir); diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 0855f77..3a48bb7 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -564,13 +564,11 @@ posix_acl_create(struct inode *dir, umode_t *mode, *acl = posix_acl_clone(p, GFP_NOFS); if (!*acl) - return -ENOMEM; + goto no_mem; ret = posix_acl_create_masq(*acl, mode); - if (ret < 0) { - posix_acl_release(*acl); - return -ENOMEM; - } + if (ret < 0) + goto no_mem_clone; if (ret == 0) { posix_acl_release(*acl); @@ -591,6 +589,12 @@ no_acl: *default_acl = NULL; *acl = NULL; return 0; + +no_mem_clone: + posix_acl_release(*acl); +no_mem: + posix_acl_release(p); + return -ENOMEM; } EXPORT_SYMBOL_GPL(posix_acl_create); @@ -772,7 +776,7 @@ posix_acl_xattr_get(struct dentry *dentry, const char *name, if (!IS_POSIXACL(dentry->d_inode)) return -EOPNOTSUPP; - if (S_ISLNK(dentry->d_inode->i_mode)) + if (d_is_symlink(dentry)) return -EOPNOTSUPP; acl = get_acl(dentry->d_inode, type); @@ -832,7 +836,7 @@ posix_acl_xattr_list(struct dentry *dentry, char *list, size_t list_size, if (!IS_POSIXACL(dentry->d_inode)) return -EOPNOTSUPP; - if (S_ISLNK(dentry->d_inode->i_mode)) + if (d_is_symlink(dentry)) return -EOPNOTSUPP; if (type == ACL_TYPE_ACCESS) diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 3309f59..be65b20 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -19,7 +19,6 @@ #include <linux/mount.h> #include <linux/init.h> #include <linux/idr.h> -#include <linux/namei.h> #include <linux/bitops.h> #include <linux/spinlock.h> #include <linux/completion.h> @@ -223,17 +222,6 @@ void proc_free_inum(unsigned int inum) spin_unlock_irqrestore(&proc_inum_lock, flags); } -static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) -{ - nd_set_link(nd, __PDE_DATA(dentry->d_inode)); - return NULL; -} - -static const struct inode_operations proc_link_inode_operations = { - .readlink = generic_readlink, - .follow_link = proc_follow_link, -}; - /* * Don't create negative dentries here, return -ENOENT by hand * instead. diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 13a50a3..7697b66 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -23,6 +23,7 @@ #include <linux/slab.h> #include <linux/mount.h> #include <linux/magic.h> +#include <linux/namei.h> #include <asm/uaccess.h> @@ -393,6 +394,26 @@ static const struct file_operations proc_reg_file_ops_no_compat = { }; #endif +static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + struct proc_dir_entry *pde = PDE(dentry->d_inode); + if (unlikely(!use_pde(pde))) + return ERR_PTR(-EINVAL); + nd_set_link(nd, pde->data); + return pde; +} + +static void proc_put_link(struct dentry *dentry, struct nameidata *nd, void *p) +{ + unuse_pde(p); +} + +const struct inode_operations proc_link_inode_operations = { + .readlink = generic_readlink, + .follow_link = proc_follow_link, + .put_link = proc_put_link, +}; + struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de) { struct inode *inode = new_inode_pseudo(sb); diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 6fcdba5..c835b94 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -200,6 +200,7 @@ struct pde_opener { int closing; struct completion *c; }; +extern const struct inode_operations proc_link_inode_operations; extern const struct inode_operations proc_pid_link_inode_operations; diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c index 04b0614..4e781e6 100644 --- a/fs/reiserfs/xattr.c +++ b/fs/reiserfs/xattr.c @@ -266,7 +266,7 @@ static int reiserfs_for_each_xattr(struct inode *inode, for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) { struct dentry *dentry = buf.dentries[i]; - if (!S_ISDIR(dentry->d_inode->i_mode)) + if (!d_is_dir(dentry)) err = action(dentry, data); dput(dentry); @@ -322,7 +322,7 @@ static int delete_one_xattr(struct dentry *dentry, void *data) struct inode *dir = dentry->d_parent->d_inode; /* This is the xattr dir, handle specially. */ - if (S_ISDIR(dentry->d_inode->i_mode)) + if (d_is_dir(dentry)) return xattr_rmdir(dir, dentry); return xattr_unlink(dir, dentry); @@ -71,7 +71,7 @@ static unsigned long super_cache_scan(struct shrinker *shrink, if (!(sc->gfp_mask & __GFP_FS)) return SHRINK_STOP; - if (!grab_super_passive(sb)) + if (!trylock_super(sb)) return SHRINK_STOP; if (sb->s_op->nr_cached_objects) @@ -105,7 +105,7 @@ static unsigned long super_cache_scan(struct shrinker *shrink, freed += sb->s_op->free_cached_objects(sb, sc); } - drop_super(sb); + up_read(&sb->s_umount); return freed; } @@ -118,7 +118,7 @@ static unsigned long super_cache_count(struct shrinker *shrink, sb = container_of(shrink, struct super_block, s_shrink); /* - * Don't call grab_super_passive as it is a potential + * Don't call trylock_super as it is a potential * scalability bottleneck. The counts could get updated * between super_cache_count and super_cache_scan anyway. * Call to super_cache_count with shrinker_rwsem held @@ -348,35 +348,31 @@ static int grab_super(struct super_block *s) __releases(sb_lock) } /* - * grab_super_passive - acquire a passive reference + * trylock_super - try to grab ->s_umount shared * @sb: reference we are trying to grab * - * Tries to acquire a passive reference. This is used in places where we + * Try to prevent fs shutdown. This is used in places where we * cannot take an active reference but we need to ensure that the - * superblock does not go away while we are working on it. It returns - * false if a reference was not gained, and returns true with the s_umount - * lock held in read mode if a reference is gained. On successful return, - * the caller must drop the s_umount lock and the passive reference when - * done. + * filesystem is not shut down while we are working on it. It returns + * false if we cannot acquire s_umount or if we lose the race and + * filesystem already got into shutdown, and returns true with the s_umount + * lock held in read mode in case of success. On successful return, + * the caller must drop the s_umount lock when done. + * + * Note that unlike get_super() et.al. this one does *not* bump ->s_count. + * The reason why it's safe is that we are OK with doing trylock instead + * of down_read(). There's a couple of places that are OK with that, but + * it's very much not a general-purpose interface. */ -bool grab_super_passive(struct super_block *sb) +bool trylock_super(struct super_block *sb) { - spin_lock(&sb_lock); - if (hlist_unhashed(&sb->s_instances)) { - spin_unlock(&sb_lock); - return false; - } - - sb->s_count++; - spin_unlock(&sb_lock); - if (down_read_trylock(&sb->s_umount)) { - if (sb->s_root && (sb->s_flags & MS_BORN)) + if (!hlist_unhashed(&sb->s_instances) && + sb->s_root && (sb->s_flags & MS_BORN)) return true; up_read(&sb->s_umount); } - put_super(sb); return false; } diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index bf70a2a..ac4feae 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -287,7 +287,7 @@ xfs_readlink_by_handle( return PTR_ERR(dentry); /* Restrict this handle operation to symlinks only. */ - if (!S_ISLNK(dentry->d_inode->i_mode)) { + if (!d_is_symlink(dentry)) { error = -EINVAL; goto out_dput; } |
