diff options
Diffstat (limited to 'fs/aufs/i_op.c')
| -rw-r--r-- | fs/aufs/i_op.c | 1477 |
1 files changed, 0 insertions, 1477 deletions
diff --git a/fs/aufs/i_op.c b/fs/aufs/i_op.c deleted file mode 100644 index 6e50526d8..000000000 --- a/fs/aufs/i_op.c +++ /dev/null @@ -1,1477 +0,0 @@ -/* - * Copyright (C) 2005-2016 Junjiro R. Okajima - */ - -/* - * inode operations (except add/del/rename) - */ - -#include <linux/device_cgroup.h> -#include <linux/fs_stack.h> -#include <linux/namei.h> -#include <linux/security.h> -#include "aufs.h" - -static int h_permission(struct inode *h_inode, int mask, - struct vfsmount *h_mnt, int brperm) -{ - int err; - const unsigned char write_mask = !!(mask & (MAY_WRITE | MAY_APPEND)); - - err = -EACCES; - if ((write_mask && IS_IMMUTABLE(h_inode)) - || ((mask & MAY_EXEC) - && S_ISREG(h_inode->i_mode) - && ((h_mnt->mnt_flags & MNT_NOEXEC) - || !(h_inode->i_mode & S_IXUGO)))) - goto out; - - /* - * - skip the lower fs test in the case of write to ro branch. - * - nfs dir permission write check is optimized, but a policy for - * link/rename requires a real check. - * - nfs always sets MS_POSIXACL regardless its mount option 'noacl.' - * in this case, generic_permission() returns -EOPNOTSUPP. - */ - if ((write_mask && !au_br_writable(brperm)) - || (au_test_nfs(h_inode->i_sb) && S_ISDIR(h_inode->i_mode) - && write_mask && !(mask & MAY_READ)) - || !h_inode->i_op->permission) { - /* AuLabel(generic_permission); */ - /* AuDbg("get_acl %pf\n", h_inode->i_op->get_acl); */ - err = generic_permission(h_inode, mask); - if (err == -EOPNOTSUPP && au_test_nfs_noacl(h_inode)) - err = h_inode->i_op->permission(h_inode, mask); - AuTraceErr(err); - } else { - /* AuLabel(h_inode->permission); */ - err = h_inode->i_op->permission(h_inode, mask); - AuTraceErr(err); - } - - if (!err) - err = devcgroup_inode_permission(h_inode, mask); - if (!err) - err = security_inode_permission(h_inode, mask); - -#if 0 - if (!err) { - /* todo: do we need to call ima_path_check()? */ - struct path h_path = { - .dentry = - .mnt = h_mnt - }; - err = ima_path_check(&h_path, - mask & (MAY_READ | MAY_WRITE | MAY_EXEC), - IMA_COUNT_LEAVE); - } -#endif - -out: - return err; -} - -static int aufs_permission(struct inode *inode, int mask) -{ - int err; - aufs_bindex_t bindex, bend; - const unsigned char isdir = !!S_ISDIR(inode->i_mode), - write_mask = !!(mask & (MAY_WRITE | MAY_APPEND)); - struct inode *h_inode; - struct super_block *sb; - struct au_branch *br; - - /* todo: support rcu-walk? */ - if (mask & MAY_NOT_BLOCK) - return -ECHILD; - - sb = inode->i_sb; - si_read_lock(sb, AuLock_FLUSH); - ii_read_lock_child(inode); -#if 0 - err = au_iigen_test(inode, au_sigen(sb)); - if (unlikely(err)) - goto out; -#endif - - if (!isdir - || write_mask - || au_opt_test(au_mntflags(sb), DIRPERM1)) { - err = au_busy_or_stale(); - h_inode = au_h_iptr(inode, au_ibstart(inode)); - if (unlikely(!h_inode - || (h_inode->i_mode & S_IFMT) - != (inode->i_mode & S_IFMT))) - goto out; - - err = 0; - bindex = au_ibstart(inode); - br = au_sbr(sb, bindex); - err = h_permission(h_inode, mask, au_br_mnt(br), br->br_perm); - if (write_mask - && !err - && !special_file(h_inode->i_mode)) { - /* test whether the upper writable branch exists */ - err = -EROFS; - for (; bindex >= 0; bindex--) - if (!au_br_rdonly(au_sbr(sb, bindex))) { - err = 0; - break; - } - } - goto out; - } - - /* non-write to dir */ - err = 0; - bend = au_ibend(inode); - for (bindex = au_ibstart(inode); !err && bindex <= bend; bindex++) { - h_inode = au_h_iptr(inode, bindex); - if (h_inode) { - err = au_busy_or_stale(); - if (unlikely(!S_ISDIR(h_inode->i_mode))) - break; - - br = au_sbr(sb, bindex); - err = h_permission(h_inode, mask, au_br_mnt(br), - br->br_perm); - } - } - -out: - ii_read_unlock(inode); - si_read_unlock(sb); - return err; -} - -/* ---------------------------------------------------------------------- */ - -static struct dentry *aufs_lookup(struct inode *dir, struct dentry *dentry, - unsigned int flags) -{ - struct dentry *ret, *parent; - struct inode *inode; - struct super_block *sb; - int err, npositive; - - IMustLock(dir); - - /* todo: support rcu-walk? */ - ret = ERR_PTR(-ECHILD); - if (flags & LOOKUP_RCU) - goto out; - - ret = ERR_PTR(-ENAMETOOLONG); - if (unlikely(dentry->d_name.len > AUFS_MAX_NAMELEN)) - goto out; - - sb = dir->i_sb; - err = si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLM); - ret = ERR_PTR(err); - if (unlikely(err)) - goto out; - - err = au_di_init(dentry); - ret = ERR_PTR(err); - if (unlikely(err)) - goto out_si; - - inode = NULL; - npositive = 0; /* suppress a warning */ - parent = dentry->d_parent; /* dir inode is locked */ - di_read_lock_parent(parent, AuLock_IR); - err = au_alive_dir(parent); - if (!err) - err = au_digen_test(parent, au_sigen(sb)); - if (!err) { - npositive = au_lkup_dentry(dentry, au_dbstart(parent), - /*type*/0); - err = npositive; - } - di_read_unlock(parent, AuLock_IR); - ret = ERR_PTR(err); - if (unlikely(err < 0)) - goto out_unlock; - - if (npositive) { - inode = au_new_inode(dentry, /*must_new*/0); - if (IS_ERR(inode)) { - ret = (void *)inode; - inode = NULL; - goto out_unlock; - } - } - - if (inode) - atomic_inc(&inode->i_count); - ret = d_splice_alias(inode, dentry); -#if 0 - if (unlikely(d_need_lookup(dentry))) { - spin_lock(&dentry->d_lock); - dentry->d_flags &= ~DCACHE_NEED_LOOKUP; - spin_unlock(&dentry->d_lock); - } else -#endif - if (inode) { - if (!IS_ERR(ret)) { - iput(inode); - if (ret && ret != dentry) - ii_write_unlock(inode); - } else { - ii_write_unlock(inode); - iput(inode); - inode = NULL; - } - } - -out_unlock: - di_write_unlock(dentry); - if (inode) { - /* verbose coding for lock class name */ - if (unlikely(S_ISLNK(inode->i_mode))) - au_rw_class(&au_di(dentry)->di_rwsem, - au_lc_key + AuLcSymlink_DIINFO); - else if (unlikely(S_ISDIR(inode->i_mode))) - au_rw_class(&au_di(dentry)->di_rwsem, - au_lc_key + AuLcDir_DIINFO); - else /* likely */ - au_rw_class(&au_di(dentry)->di_rwsem, - au_lc_key + AuLcNonDir_DIINFO); - } -out_si: - si_read_unlock(sb); -out: - return ret; -} - -/* ---------------------------------------------------------------------- */ - -struct aopen_node { - struct hlist_node hlist; - struct file *file, *h_file; -}; - -static int au_do_aopen(struct inode *inode, struct file *file) -{ - struct au_sphlhead *aopen; - struct aopen_node *node; - struct au_do_open_args args = { - .no_lock = 1, - .open = au_do_open_nondir - }; - - aopen = &au_sbi(inode->i_sb)->si_aopen; - spin_lock(&aopen->spin); - hlist_for_each_entry(node, &aopen->head, hlist) - if (node->file == file) { - args.h_file = node->h_file; - break; - } - spin_unlock(&aopen->spin); - /* AuDebugOn(!args.h_file); */ - - return au_do_open(file, &args); -} - -static int aufs_atomic_open(struct inode *dir, struct dentry *dentry, - struct file *file, unsigned int open_flag, - umode_t create_mode, int *opened) -{ - int err, h_opened = *opened; - struct dentry *parent; - struct dentry *d; - struct au_sphlhead *aopen; - struct vfsub_aopen_args args = { - .open_flag = open_flag, - .create_mode = create_mode, - .opened = &h_opened - }; - struct aopen_node aopen_node = { - .file = file - }; - - IMustLock(dir); - AuDbg("open_flag 0x%x\n", open_flag); - AuDbgDentry(dentry); - - err = 0; - if (!au_di(dentry)) { - d = aufs_lookup(dir, dentry, /*flags*/0); - if (IS_ERR(d)) { - err = PTR_ERR(d); - goto out; - } else if (d) { - /* - * obsoleted dentry found. - * another error will be returned later. - */ - d_drop(d); - dput(d); - AuDbgDentry(d); - } - AuDbgDentry(dentry); - } - - if (d_is_positive(dentry) - || d_unhashed(dentry) - || d_unlinked(dentry) - || !(open_flag & O_CREAT)) - goto out_no_open; - - err = aufs_read_lock(dentry, AuLock_DW | AuLock_FLUSH | AuLock_GEN); - if (unlikely(err)) - goto out; - - parent = dentry->d_parent; /* dir is locked */ - di_write_lock_parent(parent); - err = au_lkup_dentry(dentry, /*bstart*/0, /*type*/0); - if (unlikely(err)) - goto out_unlock; - - AuDbgDentry(dentry); - if (d_is_positive(dentry)) - goto out_unlock; - - args.file = get_empty_filp(); - err = PTR_ERR(args.file); - if (IS_ERR(args.file)) - goto out_unlock; - - args.file->f_flags = file->f_flags; - err = au_aopen_or_create(dir, dentry, &args); - AuTraceErr(err); - AuDbgFile(args.file); - if (unlikely(err < 0)) { - if (h_opened & FILE_OPENED) - fput(args.file); - else - put_filp(args.file); - goto out_unlock; - } - - /* some filesystems don't set FILE_CREATED while succeeded? */ - *opened |= FILE_CREATED; - if (h_opened & FILE_OPENED) - aopen_node.h_file = args.file; - else { - put_filp(args.file); - args.file = NULL; - } - aopen = &au_sbi(dir->i_sb)->si_aopen; - au_sphl_add(&aopen_node.hlist, aopen); - err = finish_open(file, dentry, au_do_aopen, opened); - au_sphl_del(&aopen_node.hlist, aopen); - AuTraceErr(err); - AuDbgFile(file); - if (aopen_node.h_file) - fput(aopen_node.h_file); - -out_unlock: - di_write_unlock(parent); - aufs_read_unlock(dentry, AuLock_DW); - AuDbgDentry(dentry); - if (unlikely(err)) - goto out; -out_no_open: - if (!err && !(*opened & FILE_CREATED)) { - AuLabel(out_no_open); - dget(dentry); - err = finish_no_open(file, dentry); - } -out: - AuDbg("%pd%s%s\n", dentry, - (*opened & FILE_CREATED) ? " created" : "", - (*opened & FILE_OPENED) ? " opened" : ""); - AuTraceErr(err); - return err; -} - - -/* ---------------------------------------------------------------------- */ - -static int au_wr_dir_cpup(struct dentry *dentry, struct dentry *parent, - const unsigned char add_entry, aufs_bindex_t bcpup, - aufs_bindex_t bstart) -{ - int err; - struct dentry *h_parent; - struct inode *h_dir; - - if (add_entry) - IMustLock(d_inode(parent)); - else - di_write_lock_parent(parent); - - err = 0; - if (!au_h_dptr(parent, bcpup)) { - if (bstart > bcpup) - err = au_cpup_dirs(dentry, bcpup); - else if (bstart < bcpup) - err = au_cpdown_dirs(dentry, bcpup); - else - BUG(); - } - if (!err && add_entry && !au_ftest_wrdir(add_entry, TMPFILE)) { - h_parent = au_h_dptr(parent, bcpup); - h_dir = d_inode(h_parent); - mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT); - err = au_lkup_neg(dentry, bcpup, /*wh*/0); - /* todo: no unlock here */ - mutex_unlock(&h_dir->i_mutex); - - AuDbg("bcpup %d\n", bcpup); - if (!err) { - if (d_really_is_negative(dentry)) - au_set_h_dptr(dentry, bstart, NULL); - au_update_dbrange(dentry, /*do_put_zero*/0); - } - } - - if (!add_entry) - di_write_unlock(parent); - if (!err) - err = bcpup; /* success */ - - AuTraceErr(err); - return err; -} - -/* - * decide the branch and the parent dir where we will create a new entry. - * returns new bindex or an error. - * copyup the parent dir if needed. - */ -int au_wr_dir(struct dentry *dentry, struct dentry *src_dentry, - struct au_wr_dir_args *args) -{ - int err; - unsigned int flags; - aufs_bindex_t bcpup, bstart, src_bstart; - const unsigned char add_entry - = au_ftest_wrdir(args->flags, ADD_ENTRY) - | au_ftest_wrdir(args->flags, TMPFILE); - struct super_block *sb; - struct dentry *parent; - struct au_sbinfo *sbinfo; - - sb = dentry->d_sb; - sbinfo = au_sbi(sb); - parent = dget_parent(dentry); - bstart = au_dbstart(dentry); - bcpup = bstart; - if (args->force_btgt < 0) { - if (src_dentry) { - src_bstart = au_dbstart(src_dentry); - if (src_bstart < bstart) - bcpup = src_bstart; - } else if (add_entry) { - flags = 0; - if (au_ftest_wrdir(args->flags, ISDIR)) - au_fset_wbr(flags, DIR); - err = AuWbrCreate(sbinfo, dentry, flags); - bcpup = err; - } - - if (bcpup < 0 || au_test_ro(sb, bcpup, d_inode(dentry))) { - if (add_entry) - err = AuWbrCopyup(sbinfo, dentry); - else { - if (!IS_ROOT(dentry)) { - di_read_lock_parent(parent, !AuLock_IR); - err = AuWbrCopyup(sbinfo, dentry); - di_read_unlock(parent, !AuLock_IR); - } else - err = AuWbrCopyup(sbinfo, dentry); - } - bcpup = err; - if (unlikely(err < 0)) - goto out; - } - } else { - bcpup = args->force_btgt; - AuDebugOn(au_test_ro(sb, bcpup, d_inode(dentry))); - } - - AuDbg("bstart %d, bcpup %d\n", bstart, bcpup); - err = bcpup; - if (bcpup == bstart) - goto out; /* success */ - - /* copyup the new parent into the branch we process */ - err = au_wr_dir_cpup(dentry, parent, add_entry, bcpup, bstart); - if (err >= 0) { - if (d_really_is_negative(dentry)) { - au_set_h_dptr(dentry, bstart, NULL); - au_set_dbstart(dentry, bcpup); - au_set_dbend(dentry, bcpup); - } - AuDebugOn(add_entry - && !au_ftest_wrdir(args->flags, TMPFILE) - && !au_h_dptr(dentry, bcpup)); - } - -out: - dput(parent); - return err; -} - -/* ---------------------------------------------------------------------- */ - -void au_pin_hdir_unlock(struct au_pin *p) -{ - if (p->hdir) - au_hn_imtx_unlock(p->hdir); -} - -int au_pin_hdir_lock(struct au_pin *p) -{ - int err; - - err = 0; - if (!p->hdir) - goto out; - - /* even if an error happens later, keep this lock */ - au_hn_imtx_lock_nested(p->hdir, p->lsc_hi); - - err = -EBUSY; - if (unlikely(p->hdir->hi_inode != d_inode(p->h_parent))) - goto out; - - err = 0; - if (p->h_dentry) - err = au_h_verify(p->h_dentry, p->udba, p->hdir->hi_inode, - p->h_parent, p->br); - -out: - return err; -} - -int au_pin_hdir_relock(struct au_pin *p) -{ - int err, i; - struct inode *h_i; - struct dentry *h_d[] = { - p->h_dentry, - p->h_parent - }; - - err = au_pin_hdir_lock(p); - if (unlikely(err)) - goto out; - - for (i = 0; !err && i < sizeof(h_d)/sizeof(*h_d); i++) { - if (!h_d[i]) - continue; - if (d_is_positive(h_d[i])) { - h_i = d_inode(h_d[i]); - err = !h_i->i_nlink; - } - } - -out: - return err; -} - -void au_pin_hdir_set_owner(struct au_pin *p, struct task_struct *task) -{ -#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_SMP) - p->hdir->hi_inode->i_mutex.owner = task; -#endif -} - -void au_pin_hdir_acquire_nest(struct au_pin *p) -{ - if (p->hdir) { - mutex_acquire_nest(&p->hdir->hi_inode->i_mutex.dep_map, - p->lsc_hi, 0, NULL, _RET_IP_); - au_pin_hdir_set_owner(p, current); - } -} - -void au_pin_hdir_release(struct au_pin *p) -{ - if (p->hdir) { - au_pin_hdir_set_owner(p, p->task); - mutex_release(&p->hdir->hi_inode->i_mutex.dep_map, 1, _RET_IP_); - } -} - -struct dentry *au_pinned_h_parent(struct au_pin *pin) -{ - if (pin && pin->parent) - return au_h_dptr(pin->parent, pin->bindex); - return NULL; -} - -void au_unpin(struct au_pin *p) -{ - if (p->hdir) - au_pin_hdir_unlock(p); - if (p->h_mnt && au_ftest_pin(p->flags, MNT_WRITE)) - vfsub_mnt_drop_write(p->h_mnt); - if (!p->hdir) - return; - - if (!au_ftest_pin(p->flags, DI_LOCKED)) - di_read_unlock(p->parent, AuLock_IR); - iput(p->hdir->hi_inode); - dput(p->parent); - p->parent = NULL; - p->hdir = NULL; - p->h_mnt = NULL; - /* do not clear p->task */ -} - -int au_do_pin(struct au_pin *p) -{ - int err; - struct super_block *sb; - struct inode *h_dir; - - err = 0; - sb = p->dentry->d_sb; - p->br = au_sbr(sb, p->bindex); - if (IS_ROOT(p->dentry)) { - if (au_ftest_pin(p->flags, MNT_WRITE)) { - p->h_mnt = au_br_mnt(p->br); - err = vfsub_mnt_want_write(p->h_mnt); - if (unlikely(err)) { - au_fclr_pin(p->flags, MNT_WRITE); - goto out_err; - } - } - goto out; - } - - p->h_dentry = NULL; - if (p->bindex <= au_dbend(p->dentry)) - p->h_dentry = au_h_dptr(p->dentry, p->bindex); - - p->parent = dget_parent(p->dentry); - if (!au_ftest_pin(p->flags, DI_LOCKED)) - di_read_lock(p->parent, AuLock_IR, p->lsc_di); - - h_dir = NULL; - p->h_parent = au_h_dptr(p->parent, p->bindex); - p->hdir = au_hi(d_inode(p->parent), p->bindex); - if (p->hdir) - h_dir = p->hdir->hi_inode; - - /* - * udba case, or - * if DI_LOCKED is not set, then p->parent may be different - * and h_parent can be NULL. - */ - if (unlikely(!p->hdir || !h_dir || !p->h_parent)) { - err = -EBUSY; - if (!au_ftest_pin(p->flags, DI_LOCKED)) - di_read_unlock(p->parent, AuLock_IR); - dput(p->parent); - p->parent = NULL; - goto out_err; - } - - if (au_ftest_pin(p->flags, MNT_WRITE)) { - p->h_mnt = au_br_mnt(p->br); - err = vfsub_mnt_want_write(p->h_mnt); - if (unlikely(err)) { - au_fclr_pin(p->flags, MNT_WRITE); - if (!au_ftest_pin(p->flags, DI_LOCKED)) - di_read_unlock(p->parent, AuLock_IR); - dput(p->parent); - p->parent = NULL; - goto out_err; - } - } - - au_igrab(h_dir); - err = au_pin_hdir_lock(p); - if (!err) - goto out; /* success */ - - au_unpin(p); - -out_err: - pr_err("err %d\n", err); - err = au_busy_or_stale(); -out: - return err; -} - -void au_pin_init(struct au_pin *p, struct dentry *dentry, - aufs_bindex_t bindex, int lsc_di, int lsc_hi, - unsigned int udba, unsigned char flags) -{ - p->dentry = dentry; - p->udba = udba; - p->lsc_di = lsc_di; - p->lsc_hi = lsc_hi; - p->flags = flags; - p->bindex = bindex; - - p->parent = NULL; - p->hdir = NULL; - p->h_mnt = NULL; - - p->h_dentry = NULL; - p->h_parent = NULL; - p->br = NULL; - p->task = current; -} - -int au_pin(struct au_pin *pin, struct dentry *dentry, aufs_bindex_t bindex, - unsigned int udba, unsigned char flags) -{ - au_pin_init(pin, dentry, bindex, AuLsc_DI_PARENT, AuLsc_I_PARENT2, - udba, flags); - return au_do_pin(pin); -} - -/* ---------------------------------------------------------------------- */ - -/* - * ->setattr() and ->getattr() are called in various cases. - * chmod, stat: dentry is revalidated. - * fchmod, fstat: file and dentry are not revalidated, additionally they may be - * unhashed. - * for ->setattr(), ia->ia_file is passed from ftruncate only. - */ -/* todo: consolidate with do_refresh() and simple_reval_dpath() */ -int au_reval_for_attr(struct dentry *dentry, unsigned int sigen) -{ - int err; - struct dentry *parent; - - err = 0; - if (au_digen_test(dentry, sigen)) { - parent = dget_parent(dentry); - di_read_lock_parent(parent, AuLock_IR); - err = au_refresh_dentry(dentry, parent); - di_read_unlock(parent, AuLock_IR); - dput(parent); - } - - AuTraceErr(err); - return err; -} - -int au_pin_and_icpup(struct dentry *dentry, struct iattr *ia, - struct au_icpup_args *a) -{ - int err; - loff_t sz; - aufs_bindex_t bstart, ibstart; - struct dentry *hi_wh, *parent; - struct inode *inode; - struct au_wr_dir_args wr_dir_args = { - .force_btgt = -1, - .flags = 0 - }; - - if (d_is_dir(dentry)) - au_fset_wrdir(wr_dir_args.flags, ISDIR); - /* plink or hi_wh() case */ - bstart = au_dbstart(dentry); - inode = d_inode(dentry); - ibstart = au_ibstart(inode); - if (bstart != ibstart && !au_test_ro(inode->i_sb, ibstart, inode)) - wr_dir_args.force_btgt = ibstart; - err = au_wr_dir(dentry, /*src_dentry*/NULL, &wr_dir_args); - if (unlikely(err < 0)) - goto out; - a->btgt = err; - if (err != bstart) - au_fset_icpup(a->flags, DID_CPUP); - - err = 0; - a->pin_flags = AuPin_MNT_WRITE; - parent = NULL; - if (!IS_ROOT(dentry)) { - au_fset_pin(a->pin_flags, DI_LOCKED); - parent = dget_parent(dentry); - di_write_lock_parent(parent); - } - - err = au_pin(&a->pin, dentry, a->btgt, a->udba, a->pin_flags); - if (unlikely(err)) - goto out_parent; - - a->h_path.dentry = au_h_dptr(dentry, bstart); - sz = -1; - a->h_inode = d_inode(a->h_path.dentry); - if (ia && (ia->ia_valid & ATTR_SIZE)) { - mutex_lock_nested(&a->h_inode->i_mutex, AuLsc_I_CHILD); - if (ia->ia_size < i_size_read(a->h_inode)) - sz = ia->ia_size; - mutex_unlock(&a->h_inode->i_mutex); - } - - hi_wh = NULL; - if (au_ftest_icpup(a->flags, DID_CPUP) && d_unlinked(dentry)) { - hi_wh = au_hi_wh(inode, a->btgt); - if (!hi_wh) { - struct au_cp_generic cpg = { - .dentry = dentry, - .bdst = a->btgt, - .bsrc = -1, - .len = sz, - .pin = &a->pin - }; - err = au_sio_cpup_wh(&cpg, /*file*/NULL); - if (unlikely(err)) - goto out_unlock; - hi_wh = au_hi_wh(inode, a->btgt); - /* todo: revalidate hi_wh? */ - } - } - - if (parent) { - au_pin_set_parent_lflag(&a->pin, /*lflag*/0); - di_downgrade_lock(parent, AuLock_IR); - dput(parent); - parent = NULL; - } - if (!au_ftest_icpup(a->flags, DID_CPUP)) - goto out; /* success */ - - if (!d_unhashed(dentry)) { - struct au_cp_generic cpg = { - .dentry = dentry, - .bdst = a->btgt, - .bsrc = bstart, - .len = sz, - .pin = &a->pin, - .flags = AuCpup_DTIME | AuCpup_HOPEN - }; - err = au_sio_cpup_simple(&cpg); - if (!err) - a->h_path.dentry = au_h_dptr(dentry, a->btgt); - } else if (!hi_wh) - a->h_path.dentry = au_h_dptr(dentry, a->btgt); - else - a->h_path.dentry = hi_wh; /* do not dget here */ - -out_unlock: - a->h_inode = d_inode(a->h_path.dentry); - if (!err) - goto out; /* success */ - au_unpin(&a->pin); -out_parent: - if (parent) { - di_write_unlock(parent); - dput(parent); - } -out: - if (!err) - mutex_lock_nested(&a->h_inode->i_mutex, AuLsc_I_CHILD); - return err; -} - -static int aufs_setattr(struct dentry *dentry, struct iattr *ia) -{ - int err; - struct inode *inode, *delegated; - struct super_block *sb; - struct file *file; - struct au_icpup_args *a; - - inode = d_inode(dentry); - IMustLock(inode); - - err = -ENOMEM; - a = kzalloc(sizeof(*a), GFP_NOFS); - if (unlikely(!a)) - goto out; - - if (ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) - ia->ia_valid &= ~ATTR_MODE; - - file = NULL; - sb = dentry->d_sb; - err = si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLM); - if (unlikely(err)) - goto out_kfree; - - if (ia->ia_valid & ATTR_FILE) { - /* currently ftruncate(2) only */ - AuDebugOn(!d_is_reg(dentry)); - file = ia->ia_file; - err = au_reval_and_lock_fdi(file, au_reopen_nondir, /*wlock*/1); - if (unlikely(err)) - goto out_si; - ia->ia_file = au_hf_top(file); - a->udba = AuOpt_UDBA_NONE; - } else { - /* fchmod() doesn't pass ia_file */ - a->udba = au_opt_udba(sb); - di_write_lock_child(dentry); - /* no d_unlinked(), to set UDBA_NONE for root */ - if (d_unhashed(dentry)) - a->udba = AuOpt_UDBA_NONE; - if (a->udba != AuOpt_UDBA_NONE) { - AuDebugOn(IS_ROOT(dentry)); - err = au_reval_for_attr(dentry, au_sigen(sb)); - if (unlikely(err)) - goto out_dentry; - } - } - - err = au_pin_and_icpup(dentry, ia, a); - if (unlikely(err < 0)) - goto out_dentry; - if (au_ftest_icpup(a->flags, DID_CPUP)) { - ia->ia_file = NULL; - ia->ia_valid &= ~ATTR_FILE; - } - - a->h_path.mnt = au_sbr_mnt(sb, a->btgt); - if ((ia->ia_valid & (ATTR_MODE | ATTR_CTIME)) - == (ATTR_MODE | ATTR_CTIME)) { - err = security_path_chmod(&a->h_path, ia->ia_mode); - if (unlikely(err)) - goto out_unlock; - } else if ((ia->ia_valid & (ATTR_UID | ATTR_GID)) - && (ia->ia_valid & ATTR_CTIME)) { - err = security_path_chown(&a->h_path, ia->ia_uid, ia->ia_gid); - if (unlikely(err)) - goto out_unlock; - } - - if (ia->ia_valid & ATTR_SIZE) { - struct file *f; - - if (ia->ia_size < i_size_read(inode)) - /* unmap only */ - truncate_setsize(inode, ia->ia_size); - - f = NULL; - if (ia->ia_valid & ATTR_FILE) - f = ia->ia_file; - mutex_unlock(&a->h_inode->i_mutex); - err = vfsub_trunc(&a->h_path, ia->ia_size, ia->ia_valid, f); - mutex_lock_nested(&a->h_inode->i_mutex, AuLsc_I_CHILD); - } else { - delegated = NULL; - while (1) { - err = vfsub_notify_change(&a->h_path, ia, &delegated); - if (delegated) { - err = break_deleg_wait(&delegated); - if (!err) - continue; - } - break; - } - } - /* - * regardless aufs 'acl' option setting. - * why don't all acl-aware fs call this func from their ->setattr()? - */ - if (!err && (ia->ia_valid & ATTR_MODE)) - err = vfsub_acl_chmod(a->h_inode, ia->ia_mode); - if (!err) - au_cpup_attr_changeable(inode); - -out_unlock: - mutex_unlock(&a->h_inode->i_mutex); - au_unpin(&a->pin); - if (unlikely(err)) - au_update_dbstart(dentry); -out_dentry: - di_write_unlock(dentry); - if (file) { - fi_write_unlock(file); - ia->ia_file = file; - ia->ia_valid |= ATTR_FILE; - } -out_si: - si_read_unlock(sb); -out_kfree: - kfree(a); -out: - AuTraceErr(err); - return err; -} - -#if IS_ENABLED(CONFIG_AUFS_XATTR) || IS_ENABLED(CONFIG_FS_POSIX_ACL) -static int au_h_path_to_set_attr(struct dentry *dentry, - struct au_icpup_args *a, struct path *h_path) -{ - int err; - struct super_block *sb; - - sb = dentry->d_sb; - a->udba = au_opt_udba(sb); - /* no d_unlinked(), to set UDBA_NONE for root */ - if (d_unhashed(dentry)) - a->udba = AuOpt_UDBA_NONE; - if (a->udba != AuOpt_UDBA_NONE) { - AuDebugOn(IS_ROOT(dentry)); - err = au_reval_for_attr(dentry, au_sigen(sb)); - if (unlikely(err)) - goto out; - } - err = au_pin_and_icpup(dentry, /*ia*/NULL, a); - if (unlikely(err < 0)) - goto out; - - h_path->dentry = a->h_path.dentry; - h_path->mnt = au_sbr_mnt(sb, a->btgt); - -out: - return err; -} - -ssize_t au_srxattr(struct dentry *dentry, struct au_srxattr *arg) -{ - int err; - struct path h_path; - struct super_block *sb; - struct au_icpup_args *a; - struct inode *inode, *h_inode; - - inode = d_inode(dentry); - IMustLock(inode); - - err = -ENOMEM; - a = kzalloc(sizeof(*a), GFP_NOFS); - if (unlikely(!a)) - goto out; - - sb = dentry->d_sb; - err = si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLM); - if (unlikely(err)) - goto out_kfree; - - h_path.dentry = NULL; /* silence gcc */ - di_write_lock_child(dentry); - err = au_h_path_to_set_attr(dentry, a, &h_path); - if (unlikely(err)) - goto out_di; - - mutex_unlock(&a->h_inode->i_mutex); - switch (arg->type) { - case AU_XATTR_SET: - err = vfsub_setxattr(h_path.dentry, - arg->u.set.name, arg->u.set.value, - arg->u.set.size, arg->u.set.flags); - break; - case AU_XATTR_REMOVE: - err = vfsub_removexattr(h_path.dentry, arg->u.remove.name); - break; - case AU_ACL_SET: - err = -EOPNOTSUPP; - h_inode = d_inode(h_path.dentry); - if (h_inode->i_op->set_acl) - err = h_inode->i_op->set_acl(h_inode, - arg->u.acl_set.acl, - arg->u.acl_set.type); - break; - } - if (!err) - au_cpup_attr_timesizes(inode); - - au_unpin(&a->pin); - if (unlikely(err)) - au_update_dbstart(dentry); - -out_di: - di_write_unlock(dentry); - si_read_unlock(sb); -out_kfree: - kfree(a); -out: - AuTraceErr(err); - return err; -} -#endif - -static void au_refresh_iattr(struct inode *inode, struct kstat *st, - unsigned int nlink) -{ - unsigned int n; - - inode->i_mode = st->mode; - /* don't i_[ug]id_write() here */ - inode->i_uid = st->uid; - inode->i_gid = st->gid; - inode->i_atime = st->atime; - inode->i_mtime = st->mtime; - inode->i_ctime = st->ctime; - - au_cpup_attr_nlink(inode, /*force*/0); - if (S_ISDIR(inode->i_mode)) { - n = inode->i_nlink; - n -= nlink; - n += st->nlink; - smp_mb(); /* for i_nlink */ - /* 0 can happen */ - set_nlink(inode, n); - } - - spin_lock(&inode->i_lock); - inode->i_blocks = st->blocks; - i_size_write(inode, st->size); - spin_unlock(&inode->i_lock); -} - -/* - * common routine for aufs_getattr() and aufs_getxattr(). - * returns zero or negative (an error). - * @dentry will be read-locked in success. - */ -int au_h_path_getattr(struct dentry *dentry, int force, struct path *h_path) -{ - int err; - unsigned int mnt_flags, sigen; - unsigned char udba_none; - aufs_bindex_t bindex; - struct super_block *sb, *h_sb; - struct inode *inode; - - h_path->mnt = NULL; - h_path->dentry = NULL; - - err = 0; - sb = dentry->d_sb; - mnt_flags = au_mntflags(sb); - udba_none = !!au_opt_test(mnt_flags, UDBA_NONE); - - /* support fstat(2) */ - if (!d_unlinked(dentry) && !udba_none) { - sigen = au_sigen(sb); - err = au_digen_test(dentry, sigen); - if (!err) { - di_read_lock_child(dentry, AuLock_IR); - err = au_dbrange_test(dentry); - if (unlikely(err)) { - di_read_unlock(dentry, AuLock_IR); - goto out; - } - } else { - AuDebugOn(IS_ROOT(dentry)); - di_write_lock_child(dentry); - err = au_dbrange_test(dentry); - if (!err) - err = au_reval_for_attr(dentry, sigen); - if (!err) - di_downgrade_lock(dentry, AuLock_IR); - else { - di_write_unlock(dentry); - goto out; - } - } - } else - di_read_lock_child(dentry, AuLock_IR); - - inode = d_inode(dentry); - bindex = au_ibstart(inode); - h_path->mnt = au_sbr_mnt(sb, bindex); - h_sb = h_path->mnt->mnt_sb; - if (!force - && !au_test_fs_bad_iattr(h_sb) - && udba_none) - goto out; /* success */ - - if (au_dbstart(dentry) == bindex) - h_path->dentry = au_h_dptr(dentry, bindex); - else if (au_opt_test(mnt_flags, PLINK) && au_plink_test(inode)) { - h_path->dentry = au_plink_lkup(inode, bindex); - if (IS_ERR(h_path->dentry)) - /* pretending success */ - h_path->dentry = NULL; - else - dput(h_path->dentry); - } - -out: - return err; -} - -static int aufs_getattr(struct vfsmount *mnt __maybe_unused, - struct dentry *dentry, struct kstat *st) -{ - int err; - unsigned char positive; - struct path h_path; - struct inode *inode; - struct super_block *sb; - - inode = d_inode(dentry); - sb = dentry->d_sb; - err = si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLM); - if (unlikely(err)) - goto out; - err = au_h_path_getattr(dentry, /*force*/0, &h_path); - if (unlikely(err)) - goto out_si; - if (unlikely(!h_path.dentry)) - /* illegally overlapped or something */ - goto out_fill; /* pretending success */ - - positive = d_is_positive(h_path.dentry); - if (positive) - err = vfs_getattr(&h_path, st); - if (!err) { - if (positive) - au_refresh_iattr(inode, st, - d_inode(h_path.dentry)->i_nlink); - goto out_fill; /* success */ - } - AuTraceErr(err); - goto out_di; - -out_fill: - generic_fillattr(inode, st); -out_di: - di_read_unlock(dentry, AuLock_IR); -out_si: - si_read_unlock(sb); -out: - AuTraceErr(err); - return err; -} - -/* ---------------------------------------------------------------------- */ - -/* - * Assumption: - * - the number of symlinks is not so many. - * - * Structure: - * - sbinfo (instead of iinfo) contains an hlist of struct au_symlink. - * If iinfo contained the hlist, then it would be rather large waste of memory - * I am afraid. - * - struct au_symlink contains the necessary info for h_inode follow_link() and - * put_link(). - */ - -struct au_symlink { - union { - struct hlist_node hlist; - struct rcu_head rcu; - }; - - struct inode *h_inode; - void *h_cookie; -}; - -static void au_symlink_add(struct super_block *sb, struct au_symlink *slink, - struct inode *h_inode, void *cookie) -{ - struct au_sbinfo *sbinfo; - - ihold(h_inode); - slink->h_inode = h_inode; - slink->h_cookie = cookie; - sbinfo = au_sbi(sb); - au_sphl_add(&slink->hlist, &sbinfo->si_symlink); -} - -static void au_symlink_del(struct super_block *sb, struct au_symlink *slink) -{ - struct au_sbinfo *sbinfo; - - /* do not iput() within rcu */ - iput(slink->h_inode); - slink->h_inode = NULL; - sbinfo = au_sbi(sb); - au_sphl_del_rcu(&slink->hlist, &sbinfo->si_symlink); - kfree_rcu(slink, rcu); -} - -static const char *aufs_follow_link(struct dentry *dentry, void **cookie) -{ - const char *ret; - struct inode *inode, *h_inode; - struct dentry *h_dentry; - struct au_symlink *slink; - int err; - aufs_bindex_t bindex; - - ret = NULL; /* suppress a warning */ - err = aufs_read_lock(dentry, AuLock_IR | AuLock_GEN); - if (unlikely(err)) - goto out; - - err = au_d_hashed_positive(dentry); - if (unlikely(err)) - goto out_unlock; - - err = -EINVAL; - inode = d_inode(dentry); - bindex = au_ibstart(inode); - h_inode = au_h_iptr(inode, bindex); - if (unlikely(!h_inode->i_op->follow_link)) - goto out_unlock; - - err = -ENOMEM; - slink = kmalloc(sizeof(*slink), GFP_NOFS); - if (unlikely(!slink)) - goto out_unlock; - - err = -EBUSY; - h_dentry = NULL; - if (au_dbstart(dentry) <= bindex) { - h_dentry = au_h_dptr(dentry, bindex); - if (h_dentry) - dget(h_dentry); - } - if (!h_dentry) { - h_dentry = d_find_any_alias(h_inode); - if (IS_ERR(h_dentry)) { - err = PTR_ERR(h_dentry); - goto out_free; - } - } - if (unlikely(!h_dentry)) - goto out_free; - - err = 0; - AuDbg("%pf\n", h_inode->i_op->follow_link); - AuDbgDentry(h_dentry); - ret = h_inode->i_op->follow_link(h_dentry, cookie); - dput(h_dentry); - - if (!IS_ERR_OR_NULL(ret)) { - au_symlink_add(inode->i_sb, slink, h_inode, *cookie); - *cookie = slink; - AuDbg("slink %p\n", slink); - goto out_unlock; /* success */ - } - -out_free: - slink->h_inode = NULL; - kfree_rcu(slink, rcu); -out_unlock: - aufs_read_unlock(dentry, AuLock_IR); -out: - if (unlikely(err)) - ret = ERR_PTR(err); - AuTraceErrPtr(ret); - return ret; -} - -static void aufs_put_link(struct inode *inode, void *cookie) -{ - struct au_symlink *slink; - struct inode *h_inode; - - slink = cookie; - AuDbg("slink %p\n", slink); - h_inode = slink->h_inode; - AuDbg("%pf\n", h_inode->i_op->put_link); - AuDbgInode(h_inode); - if (h_inode->i_op->put_link) - h_inode->i_op->put_link(h_inode, slink->h_cookie); - au_symlink_del(inode->i_sb, slink); -} - -/* ---------------------------------------------------------------------- */ - -static int aufs_update_time(struct inode *inode, struct timespec *ts, int flags) -{ - int err; - struct super_block *sb; - struct inode *h_inode; - - sb = inode->i_sb; - /* mmap_sem might be acquired already, cf. aufs_mmap() */ - lockdep_off(); - si_read_lock(sb, AuLock_FLUSH); - ii_write_lock_child(inode); - lockdep_on(); - h_inode = au_h_iptr(inode, au_ibstart(inode)); - err = vfsub_update_time(h_inode, ts, flags); - lockdep_off(); - if (!err) - au_cpup_attr_timesizes(inode); - ii_write_unlock(inode); - si_read_unlock(sb); - lockdep_on(); - - if (!err && (flags & S_VERSION)) - inode_inc_iversion(inode); - - return err; -} - -/* ---------------------------------------------------------------------- */ - -/* no getattr version will be set by module.c:aufs_init() */ -struct inode_operations aufs_iop_nogetattr[AuIop_Last], - aufs_iop[] = { - [AuIop_SYMLINK] = { - .permission = aufs_permission, -#ifdef CONFIG_FS_POSIX_ACL - .get_acl = aufs_get_acl, - .set_acl = aufs_set_acl, /* unsupport for symlink? */ -#endif - - .setattr = aufs_setattr, - .getattr = aufs_getattr, - -#ifdef CONFIG_AUFS_XATTR - .setxattr = aufs_setxattr, - .getxattr = aufs_getxattr, - .listxattr = aufs_listxattr, - .removexattr = aufs_removexattr, -#endif - - .readlink = generic_readlink, - .follow_link = aufs_follow_link, - .put_link = aufs_put_link, - - /* .update_time = aufs_update_time */ - }, - [AuIop_DIR] = { - .create = aufs_create, - .lookup = aufs_lookup, - .link = aufs_link, - .unlink = aufs_unlink, - .symlink = aufs_symlink, - .mkdir = aufs_mkdir, - .rmdir = aufs_rmdir, - .mknod = aufs_mknod, - .rename = aufs_rename, - - .permission = aufs_permission, -#ifdef CONFIG_FS_POSIX_ACL - .get_acl = aufs_get_acl, - .set_acl = aufs_set_acl, -#endif - - .setattr = aufs_setattr, - .getattr = aufs_getattr, - -#ifdef CONFIG_AUFS_XATTR - .setxattr = aufs_setxattr, - .getxattr = aufs_getxattr, - .listxattr = aufs_listxattr, - .removexattr = aufs_removexattr, -#endif - - .update_time = aufs_update_time, - .atomic_open = aufs_atomic_open, - .tmpfile = aufs_tmpfile - }, - [AuIop_OTHER] = { - .permission = aufs_permission, -#ifdef CONFIG_FS_POSIX_ACL - .get_acl = aufs_get_acl, - .set_acl = aufs_set_acl, -#endif - - .setattr = aufs_setattr, - .getattr = aufs_getattr, - -#ifdef CONFIG_AUFS_XATTR - .setxattr = aufs_setxattr, - .getxattr = aufs_getxattr, - .listxattr = aufs_listxattr, - .removexattr = aufs_removexattr, -#endif - - .update_time = aufs_update_time - } -}; |