void au_fhsm_wrote(struct super_block *sb, aufs_bindex_t bindex, int force) { int err; struct au_sbinfo *sbinfo; struct au_fhsm *fhsm; struct au_branch *br; struct au_br_fhsm *bf; AuDbg("b%d, force %d\n", bindex, force); SiMustAnyLock(sb); sbinfo = au_sbi(sb); fhsm = &sbinfo->si_fhsm; if (!au_ftest_si(sbinfo, FHSM) || fhsm->fhsm_bottom == bindex) return; br = au_sbr(sb, bindex); bf = br->br_fhsm; AuDebugOn(!bf); mutex_lock(&bf->bf_lock); if (force || au_fhsm_pid(fhsm) || au_fhsm_test_jiffy(sbinfo, br)) err = au_fhsm_stfs(sb, bindex, /*rstfs*/NULL, /*do_lock*/0, /*do_notify*/1); mutex_unlock(&bf->bf_lock); }
static void au_fhsm_notify(struct super_block *sb, int val) { struct au_sbinfo *sbinfo; struct au_fhsm *fhsm; SiMustAnyLock(sb); sbinfo = au_sbi(sb); fhsm = &sbinfo->si_fhsm; if (au_fhsm_pid(fhsm) && atomic_read(&fhsm->fhsm_readable) != -1) { atomic_set(&fhsm->fhsm_readable, val); if (val) wake_up(&fhsm->fhsm_wqh); } }
static int au_cmoo(struct dentry *dentry) { int err, cmoo; unsigned int udba; struct path h_path; struct au_pin pin; struct au_cp_generic cpg = { .dentry = dentry, .bdst = -1, .bsrc = -1, .len = -1, .pin = &pin, .flags = AuCpup_DTIME | AuCpup_HOPEN }; struct inode *inode, *delegated; struct super_block *sb; struct au_sbinfo *sbinfo; struct au_fhsm *fhsm; pid_t pid; struct au_branch *br; struct dentry *parent; struct au_hinode *hdir; DiMustWriteLock(dentry); inode = dentry->d_inode; IiMustWriteLock(inode); err = 0; if (IS_ROOT(dentry)) goto out; cpg.bsrc = au_dbstart(dentry); if (!cpg.bsrc) goto out; sb = dentry->d_sb; sbinfo = au_sbi(sb); fhsm = &sbinfo->si_fhsm; pid = au_fhsm_pid(fhsm); if (pid && (current->pid == pid || current->real_parent->pid == pid)) goto out; br = au_sbr(sb, cpg.bsrc); cmoo = au_br_cmoo(br->br_perm); if (!cmoo) goto out; if (!S_ISREG(inode->i_mode)) cmoo &= AuBrAttr_COO_ALL; if (!cmoo) goto out; parent = dget_parent(dentry); di_write_lock_parent(parent); err = au_wbr_do_copyup_bu(dentry, cpg.bsrc - 1); cpg.bdst = err; if (unlikely(err < 0)) { err = 0; /* there is no upper writable branch */ goto out_dgrade; } AuDbg("bsrc %d, bdst %d\n", cpg.bsrc, cpg.bdst); /* do not respect the coo attrib for the target branch */ err = au_cpup_dirs(dentry, cpg.bdst); if (unlikely(err)) goto out_dgrade; di_downgrade_lock(parent, AuLock_IR); udba = au_opt_udba(sb); err = au_pin(&pin, dentry, cpg.bdst, udba, AuPin_DI_LOCKED | AuPin_MNT_WRITE); if (unlikely(err)) goto out_parent; err = au_sio_cpup_simple(&cpg); au_unpin(&pin); if (unlikely(err)) goto out_parent; if (!(cmoo & AuBrWAttr_MOO)) goto out_parent; /* success */ err = au_pin(&pin, dentry, cpg.bsrc, udba, AuPin_DI_LOCKED | AuPin_MNT_WRITE); if (unlikely(err)) goto out_parent; h_path.mnt = au_br_mnt(br); h_path.dentry = au_h_dptr(dentry, cpg.bsrc); hdir = au_hi(parent->d_inode, cpg.bsrc); delegated = NULL; err = vfsub_unlink(hdir->hi_inode, &h_path, &delegated, /*force*/1); au_unpin(&pin); /* todo: keep h_dentry or not? */ if (unlikely(err == -EWOULDBLOCK)) { pr_warn("cannot retry for NFSv4 delegation" " for an internal unlink\n"); iput(delegated); } if (unlikely(err)) { pr_err("unlink %pd after coo failed (%d), ignored\n", dentry, err); err = 0; } goto out_parent; /* success */ out_dgrade: di_downgrade_lock(parent, AuLock_IR); out_parent: di_read_unlock(parent, AuLock_IR); dput(parent); out: AuTraceErr(err); return err; } int au_do_open(struct file *file, int (*open)(struct file *file, int flags), struct au_fidir *fidir) { int err; struct dentry *dentry; struct au_finfo *finfo; err = au_finfo_init(file, fidir); if (unlikely(err)) goto out; dentry = file->f_path.dentry; di_write_lock_child(dentry); err = au_cmoo(dentry); di_downgrade_lock(dentry, AuLock_IR); if (!err) err = open(file, vfsub_file_flags(file)); di_read_unlock(dentry, AuLock_IR); finfo = au_fi(file); if (!err) { finfo->fi_file = file; au_sphl_add(&finfo->fi_hlist, &au_sbi(file->f_path.dentry->d_sb)->si_files); } fi_write_unlock(file); if (unlikely(err)) { finfo->fi_hdir = NULL; au_finfo_fin(file); } out: return err; }