[PATCH 11/67] aufs superblock private data

From: hooanon05
Date: Fri May 16 2008 - 10:52:23 EST


From: Junjiro Okajima <hooanon05@xxxxxxxxxxx>

initial commit
aufs superblock private data

Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
---
fs/aufs/sbinfo.c | 268 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 268 insertions(+), 0 deletions(-)

diff --git a/fs/aufs/sbinfo.c b/fs/aufs/sbinfo.c
new file mode 100644
index 0000000..a412811
--- /dev/null
+++ b/fs/aufs/sbinfo.c
@@ -0,0 +1,268 @@
+/*
+ * Copyright (C) 2005-2008 Junjiro 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
+ */
+
+/*
+ * superblock private data
+ *
+ * $Id: sbinfo.c,v 1.4 2008/05/12 00:28:22 sfjro Exp $
+ */
+
+#include <linux/mnt_namespace.h>
+#include <linux/smp_lock.h>
+#include "aufs.h"
+
+/*
+ * they are necessary regardless sysfs is disabled.
+ */
+void au_si_free(struct kobject *kobj)
+{
+ struct au_sbinfo *sbinfo;
+ struct super_block *sb;
+
+ LKTRTrace("kobj %p\n", kobj);
+ sbinfo = container_of(kobj, struct au_sbinfo, si_kobj);
+ LKTRTrace("sbinfo %p\n", sbinfo);
+ AuDebugOn(!list_empty(&sbinfo->si_plink));
+
+ sb = sbinfo->si_sb;
+ if (unlikely(!au_ftest_si(sbinfo, FAILED_INIT))) {
+ au_sbilist_lock();
+ au_sbilist_del(sbinfo);
+ au_sbilist_unlock();
+ }
+
+ si_write_lock(sb);
+ au_xino_clr(sb);
+ au_br_free(sbinfo);
+ kfree(sbinfo->si_branch);
+ si_write_unlock(sb);
+
+ //AuDbg("free\n");
+ kfree(sbinfo);
+}
+
+int au_si_alloc(struct super_block *sb)
+{
+ int err;
+ struct au_sbinfo *sbinfo;
+
+ AuTraceEnter();
+
+ err = -ENOMEM;
+ sbinfo = kmalloc(sizeof(*sbinfo), GFP_KERNEL);
+ //if (LktrCond) {kfree(sbinfo); sbinfo = NULL;}
+ if (unlikely(!sbinfo))
+ goto out;
+ sbinfo->si_branch = kzalloc(sizeof(*sbinfo->si_branch), GFP_KERNEL);
+ //if (LktrCond) {kfree(sbinfo->si_branch); sbinfo->si_branch = NULL;}
+ if (unlikely(!sbinfo->si_branch))
+ goto out_sbinfo;
+
+ memset(&sbinfo->si_kobj, 0, sizeof(sbinfo->si_kobj));
+ err = sysaufs_si_init(sbinfo);
+ if (unlikely(err))
+ goto out_br;
+
+ au_rw_init_wlock(&sbinfo->si_rwsem);
+ sbinfo->si_generation = 0;
+ //sbinfo->si_generation = INT_MAX - 2;
+ sbinfo->au_si_status = 0;
+ sbinfo->si_bend = -1;
+ sbinfo->si_last_br_id = 0;
+
+ sbinfo->si_wbr_copyup = AuWbrCopyup_Def;
+ sbinfo->si_wbr_create = AuWbrCreate_Def;
+ sbinfo->si_wbr_copyup_ops = au_wbr_copyup_ops + AuWbrCopyup_Def;
+ sbinfo->si_wbr_create_ops = au_wbr_create_ops + AuWbrCreate_Def;
+
+ sbinfo->si_mntflags = AuOpt_Def;
+
+ sbinfo->si_xread = NULL;
+ sbinfo->si_xwrite = NULL;
+ sbinfo->si_xib = NULL;
+ mutex_init(&sbinfo->si_xib_mtx);
+ sbinfo->si_xib_buf = NULL;
+ /* leave si_xib_last_pindex and si_xib_next_bit */
+
+ au_nwt_init(&sbinfo->si_nowait);
+
+ sbinfo->si_rdcache = AUFS_RDCACHE_DEF * HZ;
+ sbinfo->si_dirwh = AUFS_DIRWH_DEF;
+
+ spin_lock_init(&sbinfo->si_plink_lock);
+ INIT_LIST_HEAD(&sbinfo->si_plink);
+
+ au_robr_lvma_init(sbinfo);
+
+ /* leave other members for sysaufs and si_mnt. */
+ sbinfo->si_sb = sb;
+
+ sb->s_fs_info = sbinfo;
+ //sysaufs_si_get(sb);
+
+ au_debug_sbinfo_init(sbinfo);
+ return 0; /* success */
+
+ out_br:
+ kfree(sbinfo->si_branch);
+ out_sbinfo:
+ kfree(sbinfo);
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct au_branch *au_sbr(struct super_block *sb, aufs_bindex_t bindex)
+{
+ struct au_branch *br;
+
+ SiMustAnyLock(sb);
+ AuDebugOn(bindex < 0 || au_sbend(sb) < bindex);
+ br = au_sbi(sb)->si_branch[0 + bindex];
+ AuDebugOn(!br);
+ return br;
+}
+
+au_gen_t au_sigen_inc(struct super_block *sb)
+{
+ au_gen_t gen;
+
+ SiMustWriteLock(sb);
+ gen = ++au_sbi(sb)->si_generation;
+ au_update_digen(sb->s_root);
+ au_update_iigen(sb->s_root->d_inode);
+ sb->s_root->d_inode->i_version++;
+ return gen;
+}
+
+int au_find_bindex(struct super_block *sb, struct au_branch *br)
+{
+ aufs_bindex_t bindex, bend;
+
+ bend = au_sbend(sb);
+ for (bindex = 0; bindex <= bend; bindex++)
+ if (au_sbr(sb, bindex) == br)
+ return bindex;
+ return -1;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* dentry and super_block lock. call at entry point */
+void aufs_read_lock(struct dentry *dentry, int flags)
+{
+ si_read_lock(dentry->d_sb, flags);
+ if (au_ftest_lock(flags, DW))
+ di_write_lock_child(dentry);
+ else
+ di_read_lock_child(dentry, flags);
+}
+
+void aufs_read_unlock(struct dentry *dentry, int flags)
+{
+ if (au_ftest_lock(flags, DW))
+ di_write_unlock(dentry);
+ else
+ di_read_unlock(dentry, flags);
+ si_read_unlock(dentry->d_sb);
+}
+
+void aufs_write_lock(struct dentry *dentry)
+{
+ si_write_lock(dentry->d_sb);
+ di_write_lock_child(dentry);
+}
+
+void aufs_write_unlock(struct dentry *dentry)
+{
+ di_write_unlock(dentry);
+ si_write_unlock(dentry->d_sb);
+}
+
+void aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int flags)
+{
+ AuDebugOn(d1 == d2 || d1->d_sb != d2->d_sb);
+ si_read_lock(d1->d_sb, flags);
+ di_write_lock2_child(d1, d2, au_ftest_lock(flags, DIR));
+}
+
+void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2)
+{
+ AuDebugOn(d1 == d2 || d1->d_sb != d2->d_sb);
+ di_write_unlock2(d1, d2);
+ si_read_unlock(d1->d_sb);
+}
+
+/* ---------------------------------------------------------------------- */
+
+aufs_bindex_t au_new_br_id(struct super_block *sb)
+{
+ aufs_bindex_t br_id;
+ struct au_sbinfo *sbinfo;
+
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ sbinfo = au_sbi(sb);
+ while (1) {
+ br_id = ++sbinfo->si_last_br_id;
+ if (br_id && au_br_index(sb, br_id) < 0)
+ return br_id;
+ }
+}
+
+//todo: dirty
+/*
+ * when you mntput() for the return value of this function,
+ * you have to store it to your local var.
+ * ie. never mntput si_mntcache directly.
+ */
+struct vfsmount *au_mntcache_get(struct super_block *sb)
+{
+ struct au_sbinfo *sbinfo;
+ struct mnt_namespace *ns;
+ struct vfsmount *pos, *mnt;
+
+ AuTraceEnter();
+
+ sbinfo = au_sbi(sb);
+
+ spin_lock(&sbinfo->si_mntcache_lock);
+ if (sbinfo->si_mntcache)
+ goto out;
+
+ /* vfsmount_lock is not exported */
+ //root_mnt = current->fs->root.mnt;
+ /* no get/put */
+ AuDebugOn(!current->nsproxy);
+ ns = current->nsproxy->mnt_ns;
+ AuDebugOn(!ns);
+ list_for_each_entry(pos, &ns->list, mnt_list)
+ if (pos->mnt_sb == sb) {
+ sbinfo->si_mntcache = pos;
+ break;
+ }
+ AuDebugOn(!sbinfo->si_mntcache);
+
+ out:
+ mnt = mntget(sbinfo->si_mntcache);
+ spin_unlock(&sbinfo->si_mntcache_lock);
+ return mnt;
+}
--
1.4.4.4

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