| /* |
| * Copyright (C) 2005-2013 Junjiro R. Okajima |
| * |
| * This program, aufs is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /* |
| * file private data |
| */ |
| |
| #include "aufs.h" |
| |
| void au_hfput(struct au_hfile *hf, struct file *file) |
| { |
| /* todo: direct access f_flags */ |
| if (vfsub_file_flags(file) & __FMODE_EXEC) |
| allow_write_access(hf->hf_file); |
| fput(hf->hf_file); |
| hf->hf_file = NULL; |
| atomic_dec(&hf->hf_br->br_count); |
| hf->hf_br = NULL; |
| } |
| |
| void au_set_h_fptr(struct file *file, aufs_bindex_t bindex, struct file *val) |
| { |
| struct au_finfo *finfo = au_fi(file); |
| struct au_hfile *hf; |
| struct au_fidir *fidir; |
| |
| fidir = finfo->fi_hdir; |
| if (!fidir) { |
| AuDebugOn(finfo->fi_btop != bindex); |
| hf = &finfo->fi_htop; |
| } else |
| hf = fidir->fd_hfile + bindex; |
| |
| if (hf && hf->hf_file) |
| au_hfput(hf, file); |
| if (val) { |
| FiMustWriteLock(file); |
| hf->hf_file = val; |
| hf->hf_br = au_sbr(file->f_dentry->d_sb, bindex); |
| } |
| } |
| |
| void au_update_figen(struct file *file) |
| { |
| atomic_set(&au_fi(file)->fi_generation, au_digen(file->f_dentry)); |
| /* smp_mb(); */ /* atomic_set */ |
| } |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| struct au_fidir *au_fidir_alloc(struct super_block *sb) |
| { |
| struct au_fidir *fidir; |
| int nbr; |
| |
| nbr = au_sbend(sb) + 1; |
| if (nbr < 2) |
| nbr = 2; /* initial allocate for 2 branches */ |
| fidir = kzalloc(au_fidir_sz(nbr), GFP_NOFS); |
| if (fidir) { |
| fidir->fd_bbot = -1; |
| fidir->fd_nent = nbr; |
| fidir->fd_vdir_cache = NULL; |
| } |
| |
| return fidir; |
| } |
| |
| int au_fidir_realloc(struct au_finfo *finfo, int nbr) |
| { |
| int err; |
| struct au_fidir *fidir, *p; |
| |
| AuRwMustWriteLock(&finfo->fi_rwsem); |
| fidir = finfo->fi_hdir; |
| AuDebugOn(!fidir); |
| |
| err = -ENOMEM; |
| p = au_kzrealloc(fidir, au_fidir_sz(fidir->fd_nent), au_fidir_sz(nbr), |
| GFP_NOFS); |
| if (p) { |
| p->fd_nent = nbr; |
| finfo->fi_hdir = p; |
| err = 0; |
| } |
| |
| return err; |
| } |
| |
| /* ---------------------------------------------------------------------- */ |
| |
| void au_finfo_fin(struct file *file) |
| { |
| struct au_finfo *finfo; |
| |
| au_nfiles_dec(file->f_dentry->d_sb); |
| |
| finfo = au_fi(file); |
| AuDebugOn(finfo->fi_hdir); |
| AuRwDestroy(&finfo->fi_rwsem); |
| au_cache_free_finfo(finfo); |
| } |
| |
| void au_fi_init_once(void *_finfo) |
| { |
| struct au_finfo *finfo = _finfo; |
| static struct lock_class_key aufs_fi; |
| |
| au_rw_init(&finfo->fi_rwsem); |
| au_rw_class(&finfo->fi_rwsem, &aufs_fi); |
| } |
| |
| int au_finfo_init(struct file *file, struct au_fidir *fidir) |
| { |
| int err; |
| struct au_finfo *finfo; |
| struct dentry *dentry; |
| |
| err = -ENOMEM; |
| dentry = file->f_dentry; |
| finfo = au_cache_alloc_finfo(); |
| if (unlikely(!finfo)) |
| goto out; |
| |
| err = 0; |
| au_nfiles_inc(dentry->d_sb); |
| /* verbose coding for lock class name */ |
| if (!fidir) |
| au_rw_class(&finfo->fi_rwsem, au_lc_key + AuLcNonDir_FIINFO); |
| else |
| au_rw_class(&finfo->fi_rwsem, au_lc_key + AuLcDir_FIINFO); |
| au_rw_write_lock(&finfo->fi_rwsem); |
| finfo->fi_btop = -1; |
| finfo->fi_hdir = fidir; |
| atomic_set(&finfo->fi_generation, au_digen(dentry)); |
| /* smp_mb(); */ /* atomic_set */ |
| |
| file->private_data = finfo; |
| |
| out: |
| return err; |
| } |