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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/aufs/finfo.c
Initial import
Diffstat (limited to 'fs/aufs/finfo.c')
-rw-r--r--fs/aufs/finfo.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/fs/aufs/finfo.c b/fs/aufs/finfo.c
new file mode 100644
index 000000000..7ac467cf7
--- /dev/null
+++ b/fs/aufs/finfo.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2005-2015 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * 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);
+ AuDebugOn(IS_ERR_OR_NULL(file->f_path.dentry));
+ hf->hf_file = val;
+ hf->hf_br = au_sbr(file->f_path.dentry->d_sb, bindex);
+ }
+}
+
+void au_update_figen(struct file *file)
+{
+ atomic_set(&au_fi(file)->fi_generation, au_digen(file->f_path.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_path.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_path.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;
+}